The formation of technic soil in a revegetated uranium ore waste rock pile (Limousin, France)

Science.gov (United States)

Boekhout, Flora; Gérard, Martine; Kanzari, Aisha; Calas, Georges; Descostes, Michael

2014-05-01

Mining took place in France between 1945 and 2001 during which time ~210 different sites were exploited and/or explored. A total of 76 Kt of uranium was produced, 52 Mt of ore was extracted, but also 200 Mt of waste rocks was produced, the majority of which, with uranium levels corresponding to the natural environment. So far, the processes of arenisation and technic soil formation in waste rock piles are not well understood but have important implications for understanding the environmental impact and long-term speciation of uranium. Understanding weathering processes in waste rock piles is essential to determine their environmental impact. The main objectives of this work are to assess 1) the micromorphological features and neo-formed U-bearing phases related to weathering and 2) the processes behind arenisation of the rock pile. The site that was chosen is the Vieilles Sagnes waste rock pile in Fanay (Massif Central France) that represents more or less hydrothermally altered granitic rocks that have been exposed to weathering since the construction of the waste rock pile approximately 50 years ago. Two trenches were excavated to investigate the vertical differentiation of the rock pile. This site serves as a key location for studying weathering processes of waste rock piles, as it has not been reworked after initial construction and has therefore preserved information on the original mineralogy of the waste rock pile enabling us to access post emplacement weathering processes. The site is currently overgrown by moss, meter high ferns and small trees. At present day the rock pile material can be described as hydrothermally altered rocks and rock fragments within a fine-grained silty clay matrix exposed to surface conditions and weathering. A sandy "paleo" technic soil underlies the waste rock pile and functions as a natural liner by adsorption of uranium on clay minerals. Post-mining weathering of rock-pile material is superimposed on pre-mining hydrothermal and

INVESTIGATION OF THE POTENTIAL FOR CAUSTIC STRESS CORROSION CRACKING OF A537 CARBON STEEL NUCLEAR WASTE TANKS

International Nuclear Information System (INIS)

Lam, P.

2009-01-01

The evaporator recycle streams contain waste in a chemistry and temperature regime that may be outside of the current waste tank corrosion control program, which imposes temperature limits to mitigate caustic stress corrosion cracking (CSCC). A review of the recent service history (1998-2008) of Tanks 30 and 32 showed that these tanks were operated in highly concentrated hydroxide solution at high temperature. Visual inspections, experimental testing, and a review of the tank service history have shown that CSCC has occurred in uncooled/un-stress relieved F-Area tanks. Therefore, for the Type III/IIIA waste tanks the efficacy of the stress relief of welding residual stress is the only corrosion-limiting mechanism. The objective of this experimental program is to test carbon steel small scale welded U-bend specimens and large welded plates (12 x 12 x 1 in.) in a caustic solution with upper bound chemistry (12 M hydroxide and 1 M each of nitrate, nitrite, and aluminate) and temperature (125 C). These conditions simulate worst-case situations in Tanks 30 and 32. Both as-welded and stress-relieved specimens have been tested. No evidence of stress corrosion cracking was found in the U-bend specimens after 21 days of testing. The large plate test is currently in progress, but no cracking has been observed after 9 weeks of immersion. Based on the preliminary results, it appears that the environmental conditions of the tests are unable to develop stress corrosion cracking within the duration of these tests

Selenium and Other Trace Element Mobility in Waste Products and Weathered Sediments at Parys Mountain Copper Mine, Anglesey, UK

Directory of Open Access Journals (Sweden)

Liam A. Bullock

2017-11-01

Full Text Available The Parys Mountain copper mining district (Anglesey, North Wales hosts exposed pyritic bedrock, solid mine waste spoil heaps, and acid drainage (ochre sediment deposits. Both natural and waste deposits show elevated trace element concentrations, including selenium (Se, at abundances of both economic and environmental consideration. Elevated concentrations of semi-metals such as Se in waste smelts highlight the potential for economic reserves in this and similar base metal mining sites. Selenium is sourced from the pyritic bedrock and concentrations are retained in red weathering smelt soils, but lost in bedrock-weathered soils and clays. Selenium correlates with Te, Au, Bi, Cd, Hg, Pb, S, and Sb across bedrock and weathered deposits. Man-made mine waste deposits show enrichment of As, Bi, Cu, Sb, and Te, with Fe oxide-rich smelt materials containing high Pb, up to 1.5 wt %, and Au contents, up to 1.2 ppm. The trace elements As, Co, Cu, and Pb are retained from bedrock to all sediments, including high Cu content in Fe oxide-rich ochre sediments. The high abundance and mobility of trace elements in sediments and waters should be considered as potential pollutants to the area, and also as a source for economic reserves of previously extracted and new strategic commodities.

Trace contaminant concentration affects mineral transformation and pollutant fate in hydroxide-weathered Hanford sediments

International Nuclear Information System (INIS)

Perdrial, Nicolas; Rivera, Nelson; Thompson, Aaron; O’Day, Peggy A.; Chorover, Jon

2011-01-01

Highlights: ► Fate of Sr, Cs and I tracked during hydroxide-weathering of sediments. ► pCO 2 and contaminant concentration affected mineral transformation. ► Sodalite/cancrinite formed at μM levels, chabazite at mM levels. ► Absence of CO 2 resulted in calcite dissolution and strätlingite formation. ► Trace contaminant concentrations modified their own sequestration path. - Abstract: Prior work has shown that when silicaceous sediments are infused with caustic radioactive waste, contaminant fate is tightly coupled to ensuing mineral weathering reactions. However, the effects of local aqueous geochemical conditions on these reactions are poorly studied. Thus, we varied contaminant concentration and pCO 2 during the weathering of previously uncontaminated Hanford sediments over 6 months and 1 year in a solution of caustic waste (pH 13, high ionic strength). Co-contaminants Sr, Cs and I were added at “low” (Cs/Sr: 10 −5 m; I: 10 −7 m) and “high” (Cs/Sr: 10 −3 m; I: 10 −5 m) concentrations, and headspace was held at atmospheric or undetectable ( 2 partial pressure. Solid phase characterization revealed the formation of the zeolite chabazite in “high” samples, whereas feldspathoids, sodalite and cancrinite, were formed preferentially in “low” samples. Sr, Cs and I were sequestered in all reacted sediments. Native calcite dissolution in the CO 2 -free treatment drove the formation of strätlingite (Ca 2 Al 2 SiO 7 ·8H 2 O) and diminished availability of Si and Al for feldspathoid formation. Results indicate that pCO 2 and contaminant concentrations strongly affect contaminant speciation in waste-weathered sediments, and are therefore likely to impact reaction product stability under any remediation scenario.

Cesium Removal from Savannah River Site Radioactive Waste Using the Caustic Side Solvent Extraction (CSSX) Process

International Nuclear Information System (INIS)

WALKER, DARREL

2004-01-01

Researchers at the Savannah River Technology Center (SRTC) successfully demonstrated the Caustic-Side Solvent Extraction (CSSX) process flow sheet using a 33-stage, 2-cm centrifugal contactor apparatus in two 24-hour tests using actual high level waste. Previously, we demonstrated the solvent extraction process with actual SRS HLW supernatant solution using a non-optimized solvent formulation. Following that test, the solvent system was optimized to enhance extractant solubility in the diluent by increasing the modifier concentration. We now report results of two tests with the new and optimized solvent

Soils, surficial geology, and geomorphology of the Bear Creek Valley Low-Level Waste Disposal Development and Demonstration Program site

International Nuclear Information System (INIS)

Lietzke, D.A.; Lee, S.Y.; Lambert, R.E.

1988-04-01

An intensive soil survey was conducted on the proposed Low-Level Waste Disposal Development and Demonstration Program site (LLWDDD) in Bear Creek Valley. Soils on the site were related to the underlying residuum and to the surficial colluvium and alluvium. Within any particular geologic formation, soils were subdivided based mostly on the degree of weathering, as reflected by saprolite weathering and morphologic features of the soils. Degree of weathering was related both to slope shape and gradient and to the joint-fracture system. Erosion classes were also used to make further subdivisions of any particular soil. Deep pits were dug in each of the major Conasauga Group formations (Pumpkin Valley, Rogersville, Maryville, and Nolichucky) for soil and saprolite characterization. Because of the widespread presence of alluvium and colluvium, which are potential sources of fill and final cover material, pits and trenches were dug to characterize the properties of these soils and to try to understand the past geomorphic history of the site. The results of the soil survey investigation indicated that the deeply weathered Pumpkin Valley residuum has good potential for the construction of tumuli or other types of belowground or aboveground burial of prepackaged compacted waste. 11 refs., 30 figs., 3 tabs

Uranium migration and retention during weathering of a granitic waste rock pile

International Nuclear Information System (INIS)

Boekhout, F.; Gérard, M.; Kanzari, A.; Michel, A.; Déjeant, A.; Galoisy, L.; Calas, G.; Descostes, M.

2015-01-01

Highlights: • We investigate the environmental impact of the granitic waste rock piles. • The majority of the waste rocks in the pile is barren- or overburden rock. • The main neo-formed U-bearing phases are (Ca) and (Cu) uranyl phosphates. • Under circum-neutral pH conditions they do not pose an environment threat. - Abstract: This study investigates the post-mining evolution of S-type granitic waste rocks around a former uranium mine, Vieilles Sagnes (Haute Vienne, NW Massif Central, France). This mine was operated between 1957 and 1965 in the La Crouzille former world-class uranium mining district and is representative of intra-granitic vein-type deposits. 50 years after mine closure and the construction and subsequent re-vegetation of the granitic waste rock pile, we evaluate the environmental evolution of the rock pile, including rock alteration, neo-formation of U-bearing phases during weathering, and U migration. Vertical trenches have been excavated through the rock pile down to an underlying paleo-soil, allowing the investigation of the vertical differentiation of the rock pile and its influence on water pathways, weathering processes and U migration and retention. Arenization dominantly drives liberation of U, by dissolution of uraninite inclusions in the most alterable granitic minerals (i.e. K-feldspar and biotite). Retention of U in the matrix at the base of the waste rock pile, and in the underlying paleo-soil most likely occurs by precipitation of (nano-) uranyl phosphates or a combination of co-precipitation and adsorption reactions of U onto Fe (oxy)hydroxides and/or clay minerals. Even though U-migration was observed, U is retained in stable secondary mineral phases, provided the current conditions will not be modified

In-situ caustic generation from sewage: the impact of caustic strength and sewage composition.

Science.gov (United States)

Pikaar, Ilje; Rozendal, René A; Rabaey, Korneel; Yuan, Zhiguo

2013-10-01

Periodic caustic dosage is a commonly used method by the water industry to elevate pH levels and deactivate sewer biofilms responsible for hydrogen sulfide generation. Caustic (NaOH) can be generated in-situ from sewage using a divided electrochemical cell, which avoids the need for transport, handling and storage of concentrated caustic solutions. In this study, we investigated the impact of caustic strength in the cathode compartment and the impact of sodium concentration in sewage on the Coulombic efficiency (CE) for caustic generation. The CE was found to be independent of the caustic strength produced in the range of up to ~3 wt%. Results showed that a caustic solution of ~3 wt% could be produced directly from sewage at a CE of up to 75 ± 0.5%. The sodium concentration in sewage had a significant impact on the CE for caustic generation as well as on the energy requirements of the system, with a higher sodium concentration leading to a higher CE and lower energy consumption. The proton, calcium, magnesium and ammonium concentrations in sewage affected the CE for caustic generation, especially at low sodium concentrations. Economical assessment based on the experimental results indicated that sulfide control in sewers using electrochemically-generated caustic from sewage is an economically attractive strategy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Matrix effects in applying mono- and polyclonal ELISA systems to the analysis of weathered oils in contaminated soil.

Science.gov (United States)

Pollard, S J T; Farmer, J G; Knight, D M; Young, P J

2002-01-01

Commercial mono- and polyclonal enzyme-linked immunosorbent assay (ELISA) systems were applied to the on-site analysis of weathered hydrocarbon-contaminated soils at a former integrated steelworks. Comparisons were made between concentrations of solvent extractable matter (SEM) determined gravimetrically by Soxhlet (dichloromethane) extraction and those estimated immunologically by ELISA determination over a concentration range of 2000-330,000 mg SEM/kg soil dry weight. Both ELISA systems tinder-reported for the more weathered soil samples. Results suggest this is due to matrix effects in the sample rather than any inherent bias in the ELISA systems and it is concluded that, for weathered hydrocarbons typical of steelworks and coke production sites, the use of ELISA requires careful consideration as a field technique. Consideration of the target analyte relative to the composition of the hydrocarbon waste encountered appears critical.

Release of Aged Contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

Energy Technology Data Exchange (ETDEWEB)

Chorover, Jon [Univ. of Arizona, Tucson, AZ (United States); Perdrial, Nico [Univ. of Arizona, Tucson, AZ (United States); Mueller, Karl [Pennsylvania State Univ., University Park, PA (United States); Strepka, Caleb [Pennsylvania State Univ., University Park, PA (United States); O' Day, Peggy [Univ. of California, Merced, CA (United States); Rivera, Nelson [Univ. of California, Merced, CA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chang, Hyun-Shik [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steefel, Carl [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Thompson, Aaron [Univ. of Georgia, Athens, GA (United States)

2012-08-14

Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake (Chorover et al., 2008). In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, P_CO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. Below, we provide some detailed descriptions of our results from this three year study, recently completed following a one-year no cost extension.

Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

Energy Technology Data Exchange (ETDEWEB)

Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; O’Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

2012-11-05

Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

Imaging and Analytical Approaches for Characterization of Soil Mineral Weathering

Energy Technology Data Exchange (ETDEWEB)

Dohnalkova, Alice; Arey, Bruce; Varga, Tamas; Miller, Micah; Kovarik, Libor

2017-07-01

Soil minerals weathering is the primary natural source of nutrients necessary to sustain productivity in terrestrial ecosystems. Soil microbial communities increase soil mineral weathering and mineral-derived nutrient availability through physical and chemical processes. Rhizosphere, the zone immediately surrounding plant roots, is a biogeochemical hotspot with microbial activity, soil organic matter production, mineral weathering, and secondary phase formation all happening in a small temporally ephemeral zone of steep geochemical gradients. The detailed exploration of the micro-scale rhizosphere is essential to our better understanding of large-scale processes in soils, such as nutrient cycling, transport and fate of soil components, microbial-mineral interactions, soil erosion, soil organic matter turnover and its molecular-level characterization, and predictive modeling.

EFRT M-12 Issue Resolution: Caustic Leach Rate Constants from PEP and Laboratory-Scale Tests

Energy Technology Data Exchange (ETDEWEB)

Mahoney, Lenna A.; Rassat, Scot D.; Eslinger, Paul W.; Aaberg, Rosanne L.; Aker, Pamela M.; Golovich, Elizabeth C.; Hanson, Brady D.; Hausmann, Tom S.; Huckaby, James L.; Kurath, Dean E.; Minette, Michael J.; Sundaram, S. K.; Yokuda, Satoru T.

2009-08-14

Testing Summary Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes.” The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is added to the waste slurry in the vessels to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by a heating step that uses direct injection of steam to accelerate the leaching process. Following the caustic leach, the vessel contents are cooled using vessel cooling jackets and/or external heat exchangers. The main difference between the two scenarios is that for leaching in UFP-1, the 19-M NaOH is added to un-concentrated waste slurry (3 to 8 wt% solids), while for leaching in UFP-2, the slurry is

EFRT M-12 Issue Resolution: Caustic Leach Rate Constants from PEP and Laboratory-Scale Tests

International Nuclear Information System (INIS)

Mahoney, Lenna A.; Rassat, Scot D.; Eslinger, Paul W.; Aaberg, Rosanne L.; Aker, Pamela M.; Golovich, Elizabeth C.; Hanson, Brady D.; Hausmann, Tom S.; Huckaby, James L.; Kurath, Dean E.; Minette, Michael J.; Sundaram, S. K.; Yokuda, Satoru T.

2009-01-01

Testing Summary Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed and constructed and is to be operated as part of a plan to respond to issue M12, 'Undemonstrated Leaching Processes.' The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP; vessels UFP-VSL-00001A and B in the WTP PTF). In both scenarios, 19-M sodium hydroxide solution (NaOH, caustic) is added to the waste slurry in the vessels to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by a heating step that uses direct injection of steam to accelerate the leaching process. Following the caustic leach, the vessel contents are cooled using vessel cooling jackets and/or external heat exchangers. The main difference between the two scenarios is that for leaching in UFP-1, the 19-M NaOH is added to un-concentrated waste slurry (3 to 8 wt% solids), while for leaching in UFP-2, the slurry is concentrated

Washing and caustic leaching of Hanford tank sludge: Results of FY 1997 studies

International Nuclear Information System (INIS)

Lumetta, G.J.; Burgeson, I.E.; Wagner, M.J.; Liu, J.; Chen, Y.L.

1997-08-01

The current plan for remediating the Hanford tank farms consists of waste retrieval, pretreatment, treatment (immobilization), and disposal. The tank wastes will be partitioned into high-level and low-level fractions. The HLW will be immobilized in a borosilicate glass matrix; the resulting glass canisters will then be disposed of in a geologic repository. Because of the expected high cost of HLW vitrification and geologic disposal, pretreatment processes will be implemented to reduce the volume of immobilized high-level waste (IHLW). Caustic leaching (sometimes referred to as enhanced sludge washing or ESW) represents the baseline method for pretreating Hanford tank sludges. Caustic leaching is expected to remove a large fraction of the Al, which is present in large quantities in Hanford tank sludges. A significant portion of the P is also expected to be removed from the sludge by metathesis of water-insoluble metal phosphates to insoluble hydroxides and soluble Na 3 PO 4 . Similar metathesis reactions can occur for insoluble sulfate salts, allowing the removal of sulfate from the HLW stream. This report describes the sludge washing and caustic leaching tests performed at the Pacific Northwest National Laboratory in FY 1996. The sludges used in this study were taken from Hanford tanks AN-104, BY-108, S-101, and S-111

Modeling the influence of organic acids on soil weathering

Science.gov (United States)

Lawrence, Corey R.; Harden, Jennifer W.; Maher, Kate

2014-01-01

Biological inputs and organic matter cycling have long been regarded as important factors in the physical and chemical development of soils. In particular, the extent to which low molecular weight organic acids, such as oxalate, influence geochemical reactions has been widely studied. Although the effects of organic acids are diverse, there is strong evidence that organic acids accelerate the dissolution of some minerals. However, the influence of organic acids at the field-scale and over the timescales of soil development has not been evaluated in detail. In this study, a reactive-transport model of soil chemical weathering and pedogenic development was used to quantify the extent to which organic acid cycling controls mineral dissolution rates and long-term patterns of chemical weathering. Specifically, oxalic acid was added to simulations of soil development to investigate a well-studied chronosequence of soils near Santa Cruz, CA. The model formulation includes organic acid input, transport, decomposition, organic-metal aqueous complexation and mineral surface complexation in various combinations. Results suggest that although organic acid reactions accelerate mineral dissolution rates near the soil surface, the net response is an overall decrease in chemical weathering. Model results demonstrate the importance of organic acid input concentrations, fluid flow, decomposition and secondary mineral precipitation rates on the evolution of mineral weathering fronts. In particular, model soil profile evolution is sensitive to kaolinite precipitation and oxalate decomposition rates. The soil profile-scale modeling presented here provides insights into the influence of organic carbon cycling on soil weathering and pedogenesis and supports the need for further field-scale measurements of the flux and speciation of reactive organic compounds.

Wireless sensor network for monitoring soil moisture and weather conditions

Science.gov (United States)

A wireless sensor network (WSN) was developed and deployed in three fields to monitor soil water status and collect weather data for irrigation scheduling. The WSN consists of soil-water sensors, weather sensors, wireless data loggers, and a wireless modem. Soil-water sensors were installed at three...

Root-driven Weathering Impacts on Mineral-Organic Associations in Deep Soil

Science.gov (United States)

Keiluweit, M.; Garcia Arredondo, M.; Tfaily, M. M.; Kukkadapu, R. K.; Schulz, M. S.; Lawrence, C. R.

2017-12-01

Plant roots dramatically reshape the soil environments through the release of organic compounds. While root-derived organic compounds are recognized as an important source of soil C, their role in promoting weathering reactions has largely been overlooked. On the one hand, root-driven weathering may generate mineral-organic associations, which can protect soil C for centuries to millennia. On the other hand, root-driven weathering also transforms minerals, potentially disrupting protective mineral-organic associations in the process. Hence root-derived C may not only initiate C accumulation, but also diminish C stocks through disruption of mineral-organic associations. Here we determined the impact of rhizogenic weathering on mineral-organic associations, and associated changes in C storage, across the Santa Cruz Marine Terrace chronosequence (65ka-226ka). Using a combination of high-resolution mass spectrometry, Mössbauer, and X-ray (micro)spectroscopy, we examined mineral-organic associations of deep soil horizons characterized by intense rhizogenic weathering gradients. Initial rhizogenic weathering dramatically increased C stocks, which is directly linked to an increase of microbially-derived C bound to monomeric Fe and Al and nano-goethite. As weathering proceeded, the soil C stocks declined concurrent with an increasingly plant-derived C signature and decreasing crystallinity. X-ray spectromicroscopic analyses revealed strong spatial associations between C and Fe during initial weathering stages, indicative of protective mineral-organic associations. In contrast, later weathering stages showed weaker spatial relationships between C and Fe. We conclude that rhizogenic weathering enhance C storage by creating protective mineral-organic associations in the initial weathering stages. As root-driven weathering proceeds, minerals are transformed into more crystalline phases that retain lower amounts of C. Our results demonstrate that root-induced weathering

Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

International Nuclear Information System (INIS)

Francis, A.J.

1993-07-01

A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and actinides, and may involve formation of a bidentate, tridentate, binuclear, or polynuclear complex species. The extract containing radionuclide/metal complex is then subjected to microbiological degradation followed by photochemical degradation under aerobic conditions. Several metal citrate complexes are biodegraded and the metals are recovered in a concentrated form with the bacterial biomass. Uranium forms binuclear complex with citric acid and is not biodegraded. The supernatant containing uranium citrate complex is separated and upon exposure to light, undergoes rapid degradation resulting in the formation of an insoluble, stable polymeric form of uranium. Uranium is recovered as a precipitate (uranium trioxide) in a concentrated form for recycling or for appropriate disposal. This treatment process, unlike others which use caustic reagents, does not create additional hazardous wastes for disposal and causes little damage to soil which can then be returned to normal use

Safety basis for the 241-AN-107 mixer pump installation and caustic addition

International Nuclear Information System (INIS)

Van Vleet, R.J.

1994-01-01

This safety Basis was prepared to determine whether or not the proposed activities of installing a 76 HP jet mixer pump and the addition of approximately 50,000 gallons of 19 M (50:50 wt %) aqueous caustic are within the safety envelope as described by Tank Farms (chapter six of WHC-SD-WM-ISB-001, Rev. 0). The safety basis covers the components, structures and systems for the caustic addition and mixer pump installation. These include: installation of the mixer pump and monitoring equipment; operation of the mixer pump, process monitoring equipment and caustic addition; the pump stand, caustic addition skid, the electrical skid, the video camera system and the two densitometers. Also covered is the removal and decontamination of the mixer pump and process monitoring system. Authority for this safety basis is WHC-IP-0842 (Waste Tank Administration). Section 15.9, Rev. 2 (Unreviewed Safety Questions) of WHC-IP-0842 requires that an evaluation be performed for all physical modifications

Caustic Recycling Pilot Unit to Separate Sodium from LLW at Hanford Site - 12279

Energy Technology Data Exchange (ETDEWEB)

Pendleton, Justin; Bhavaraju, Sai; Priday, George; Desai, Aditya; Duffey, Kean; Balagopal, Shekar [Ceramatec Inc., Salt Lake City, UT 84119 (United States)

2012-07-01

As part of the Department of Energy (DOE) sponsored Advanced Remediation Technologies initiative, a scheme was developed to combine Continuous Sludge Leaching (CSL), Near-Tank Cesium Removal (NTCR), and Caustic Recycling Unit (CRU) using Ceramatec technology, into a single system known as the Pilot Near-Tank Treatment System (PNTTS). The Cesium (Cs) decontaminated effluent from the NTCR process will be sent to the caustic recycle process for recovery of the caustic which will be reused in another cycle of caustic leaching in the CSL process. Such an integrated mobile technology demonstration will give DOE the option to insert this process for sodium management at various sites in Hanford, and will minimize the addition of further sodium into the waste tanks. This allows for recycling of the caustic used to remove aluminum during sludge washing as a pretreatment step in the vitrification of radioactive waste which will decrease the Low Level Waste (LLW) volume by as much as 39%. The CRU pilot process was designed to recycle sodium in the form of pure sodium hydroxide. The basis for the design of the 1/4 scale pilot caustic recycling unit was to demonstrate the efficient operation of a larger scale system to recycle caustic from the NTCR effluent stream from the Parsons process. The CRU was designed to process 0.28 liter/minute of NTCR effluent, and generate 10 M concentration of 'usable' sodium hydroxide. The proposed process operates at 40 deg. C to provide additional aluminum solubility and then recover the sodium hydroxide to the point where the aluminum is saturated at 40 deg. C. A system was developed to safely separate and vent the gases generated during operation of the CRU with the production of 10 M sodium hydroxide. Caustic was produced at a rate between 1.9 to 9.3 kg/hr. The CRU was located inside an ISO container to allow for moving of the unit close to tank locations to process the LLW stream. Actual tests were conducted with the NTCR effluent

Caustic leaching of composite AZ-101/AZ-102 Hanford tank sludge

International Nuclear Information System (INIS)

Rapko, B.M.; Wagner, M.J.

1997-07-01

To reduce the quantity (and hence the cost) of glass canisters needed for disposing of high-level radioactive wastes from the Hanford tank farms, pretreatment processes are needed to remove as much nonradioactive material as possible. This report describes the results of a laboratory-scale caustic leaching test performed on a composite derived from a combination of 241-AZ-101 and 241-AZ-102 Hanford Tank sludges. The goals of this FY 1996 test were to evaluate the effectiveness of caustic leaching on removing key components from the sludge and to evaluate the effectiveness of varying the free-hydroxide concentrations by incrementally increasing the free hydroxide concentration of the leach steps up to 3 M free hydroxide. Particle-size analysis of the treated and untreated sludge indicated that the size and range of the sludge particles remained essentially unchanged by the caustic leaching treatment. Both before and after caustic leaching, a particle range of 0.2 microm to 50 microm was observed, with mean particle diameters of 8.5 to 9 microm based on the volume distribution and mean particle diameters of 0.3 to 0.4 microm based on the number distribution

Soil survey of Solid Waste Storage Area 6

International Nuclear Information System (INIS)

Lietzke, D.A.; Lee, S.Y.

1986-06-01

An intensive soil survey was made of Solid Waste Storage Area (SWSA) 6 (Oak Ridge National Laboratory) at a scale of 1:1200. The amount of chemical weathering, the thickness of upland soils, and the depth to unoxidized rock are dependent on slope gradient, water-flow pathways, degree of rock fracturing, and the extent of soil and rock erosion by late Pleistocene and Holocene geomorphic processes. Foot-slope landforms have generally concave slope shapes where sediment accumulates. Colluvium stratigraphy exhibits at least one lithologic discontinuity, but there may be two discontinuities preserved in some thicker colluvia. One or more paleosols, either complete or partially truncated, are preserved in these concave landforms. Alluvial soils were not examined in detail but were separated from colluvial soils because of their wetness. A small area of ancient alluvium was located on a stable upland summit that formed the highest elevation in SWSA-6. On the nearly level summit, a thin loess cap was preserved on the older alluvial soil. Upland and colluvial soils are all highly leached and strongly acid even though they are formed from a calcareous parent rock. The highly fractured rock, being relatively permeable, has been leached free of carbonates in the upper levels so that there is a wide pH gradient from the surface downward. Most of the soils were classified as Ultisols, with minimal areas of Alfisols, Inceptisols, and Entisols. Based on the soil survey, representative landforms and soils will be selected to study physical, chemical, and mineralogical properties of the soil and weathered rock. Those properties will be used to predict both the amount and duration of leachate filtration and purification in downward migration to the water table or lateral migration through colluvial and alluvial soils to ground-water seeps

Caustics and Caustic-Interference in Measurements of Contact Angle and Flow Visualization Through Laser Shadowgraphy

Science.gov (United States)

Chao, David F.; Zhang, Neng-Li

2002-01-01

As one of the basic elements of the shadowgraphy optical system, the image of the far field from the droplet implicates plentiful information on the droplet profile. An analysis of caustics by wave theory shows that a droplet with a cylindrically symmetric Gaussian-hill-type profile produces a circular directional caustic in far field, which arises from the singularities (inflection line on the surface). The sessile liquid droplets, which profiles are restricted by surface tension, usually have a 'protruding foot' where the surface inflects. Simple geometrical optics indicates that the circular caustic stemming from the surface inflection at the protruding-foot takes the shape of the outmost ring on the image of the far field. It is the diameter of the outmost ring that is used as one of the key parameters in the measurements of contact angle through the laser shadowgraphic method. Different surface characteristics of the droplets produce different type of caustics, and therefore, the shape of the caustics can be used to determine the surface property of the sessile droplets. The present paper describes the measurement method of contact angIe using the circular caustics and the estimation of the protruding-foot height through the caustic interference.

Causticizing for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

Scott Sinquefeld; James Cantrell; Xiaoyan Zeng; Alan Ball; Jeff Empie

2009-01-07

The cost-benefit outlook of black liquor gasification (BLG) could be greatly improved if the smelt causticization step could be achieved in situ during the gasification step. Or, at a minimum, the increase in causticizing load associated with BLG could be mitigated. A number of chemistries have been proven successful during black liquor combustion. In this project, three in situ causticizing processes (titanate, manganate, and borate) were evaluated under conditions suitable for high temperature entrained flow BLG, and low temperature steam reforming of black liquor. The evaluation included both thermodynamic modeling and lab experimentation. Titanate and manganate were tested for complete direct causticizing (to thus eliminate the lime cycle), and borates were evaluated for partial causticizing (to mitigate the load increase associated with BLG). Criteria included high carbonate conversion, corresponding hydroxide recovery upon hydrolysis, non process element (NPE) removal, and economics. Of the six cases (three chemistries at two BLG conditions), only two were found to be industrially viable: titanates for complete causticizing during high temperature BLG, and borates for partial causticizing during high temperature BLG. These two cases were evaluated for integration into a gasification-based recovery island. The Larsen [28] BLG cost-benefit study was used as a reference case for economic forecasting (i.e. a 1500 tpd pulp mill using BLG and upgrading the lime cycle). By comparison, using the titanate direct causticizing process yielded a net present value (NPV) of $25M over the NPV of BLG with conventional lime cycle. Using the existing lime cycle plus borate autocausticizing for extra capacity yielded a NPV of $16M.

Spatial patterns and controls of soil chemical weathering rates along a transient hillslope

Science.gov (United States)

Yoo, K.; Mudd, S.M.; Sanderman, J.; Amundson, Ronald; Blum, A.

2009-01-01

Hillslopes have been intensively studied by both geomorphologists and soil scientists. Whereas geomorphologists have focused on the physical soil production and transport on hillslopes, soil scientists have been concerned with the topographic variation of soil geochemical properties. We combined these differing approaches and quantified soil chemical weathering rates along a grass covered hillslope in Coastal California. The hillslope is comprised of both erosional and depositional sections. In the upper eroding section, soil production is balanced by physical erosion and chemical weathering. The hillslope then transitions to a depositional slope where soil accumulates due to a historical reduction of channel incision at the hillslope's base. Measurements of hillslope morphology and soil thickness were combined with the elemental composition of the soil and saprolite, and interpreted through a process-based model that accounts for both chemical weathering and sediment transport. Chemical weathering of the minerals as they moved downslope via sediment transport imparted spatial variation in the geochemical properties of the soil. Inverse modeling of the field and laboratory data revealed that the long-term soil chemical weathering rates peak at 5 g m- 2 yr- 1 at the downslope end of the eroding section and decrease to 1.5 g m- 2 yr- 1 within the depositional section. In the eroding section, soil chemical weathering rates appear to be primarily controlled by the rate of mineral supply via colluvial input from upslope. In the depositional slope, geochemical equilibrium between soil water and minerals appeared to limit the chemical weathering rate. Soil chemical weathering was responsible for removing 6% of the soil production in the eroding section and 5% of colluvial influx in the depositional slope. These were among the lowest weathering rates reported for actively eroding watersheds, which was attributed to the parent material with low amount of weatherable

Microwave-Assisted Sample Treatment in a Fully Automated Flow-Based Instrument: Oxidation of Reduced Technetium Species in the Analysis of Total Technetium-99 in Caustic Aged Nuclear Waste Samples

International Nuclear Information System (INIS)

Egorov, Oleg B.; O'Hara, Matthew J.; Grate, Jay W.

2004-01-01

An automated flow-based instrument for microwave-assisted treatment of liquid samples has been developed and characterized. The instrument utilizes a flow-through reaction vessel design that facilitates the addition of multiple reagents during sample treatment, removal of the gaseous reaction products, and enables quantitative removal of liquids from the reaction vessel for carryover-free operations. Matrix modification and speciation control chemistries that are required for the radiochemical determination of total 99Tc in caustic aged nuclear waste samples have been investigated. A rapid and quantitative oxidation procedure using peroxydisulfate in acidic solution was developed to convert reduced technetium species to pertechnetate in samples with high content of reducing organics. The effectiveness of the automated sample treatment procedures has been validated in the radiochemical analysis of total 99Tc in caustic aged nuclear waste matrixes from the Hanford site

Chemical weathering and loess inputs to soils in New Zealand's Wairarapa region

Science.gov (United States)

Lukens, C. E.; Norton, K. P.

2017-12-01

Geochemical mass-balance approaches are commonly used in soils to evaluate patterns in chemical weathering. In conjuction with cosmogenic nuclide measurements of total denudation or soil production, mass-balance approaches have been used to constrain rates of chemical weathering across a variety of landscapes. Here we present geochemical data from a series of soil pits in the Wairarapa region of New Zealand's North Island, where rates of soil production equal rates of total denudation measured using 10Be at sites nearby (i.e., the landscape is in steady state). Soil density increases with depth, consistent with steady weathering over the average soil residence time. However, soil geochemistry indicates very little chemical weathering has occurred, and immobile elements (Zr, Ti, and V) are depleted in soils relative to bedrock. This is contrary to the expected observation, wherein immobile elements should be enriched in soils relative to parent bedrock as weathered mobile solutes are progressively removed from soil. Our geochemical measurements suggest contributions from an exernal source, which has a different chemical composition than the underlying bedrock. We hypothesize that loess constitutes a substantial influx of additional material, and use a mixing model to predict geochemical patterns within soil columns. We evaluate the relative contributions of several likely loess sources, including tephra from the nearby Taupo Volcanic Center, local loess deposits formed during glacial-interglacial transitions, and far-travelling Australian dust. Using an established mass-balance approach with multiple immobile elements, we calculate the fraction of mass in soils contributed by loess to be as much as 25%. Combined with 10Be-derived estimates of soil production, we calculate average loess fluxes up to 320 t/km2/yr, which are consistent with previous estimates of loess acculumation over the late Holocene. Accounting for loess input, we find that chemical weathering

EFRT M-12 Issue Resolution: Caustic-Leach Rate Constants from PEP and Laboratory-Scale Tests

Energy Technology Data Exchange (ETDEWEB)

Mahoney, Lenna A.; Rassat, Scot D.; Eslinger, Paul W.; Aaberg, Rosanne L.; Aker, Pamela M.; Golovich, Elizabeth C.; Hanson, Brady D.; Hausmann, Tom S.; Huckaby, James L.; Kurath, Dean E.; Minette, Michael J.; Sundaram, S. K.; Yokuda, Satoru T.

2010-01-01

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, “Undemonstrated Leaching Processes” of the External Flowsheet Review Team (EFRT) issue response plan.( ) The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. The work described in this report addresses caustic leaching under WTP conditions, based on tests performed with a Hanford waste simulant. Because gibbsite leaching kinetics are rapid (gibbsite is expected to be dissolved by the time the final leach temperature is reached), boehmite leach kinetics are the main focus of the caustic-leach tests. The tests were completed at the laboratory-scale and in the PEP, which is a 1/4.5-scale mock-up of key PTF process equipment. Two laboratory-scale caustic-leach tests were performed for each of the PEP runs. For each PEP run, unleached slurry was taken from the PEP caustic-leach vessel for one batch and used as feed for both of the corresponding laboratory-scale tests.

Concentrating on caustic

International Nuclear Information System (INIS)

Collins, Richard

2010-01-01

in the chosen medium (wastewater) and passes electrons freed up in the process around a circuit from the anode side to the cathode, generating electricity. The protons diffuse through the liquid and a membrane to the cathode, where they re-bond with the electrons and oxygen to create water, keeping the entire system neutral. Use wastewater as the medium though, and the high levels of sodium means that rather than the protons, sodium is preferentially transferred to the cathode, preventing the full reduction of oxygen to water. Instead, hydroxyl (OH) is created, which then bonds with the sodium to create sodium hydroxide (NaOH) in a continuous process. Unlike with the electricity generation trials, the theoretical capacity of the bioelectrochemical system to produce sodium hydroxide is compelling and cost-effective. “The process is pretty successful thus far. Per kilogram of organics we remove in an anode, we can think about 5kg of caustic soda on the cathode side,” said Dr Rabeay. “You need a very small number of electrons to make sodium hydroxide and the organic matter contains a lot of electrons, it is very electron-rich.” While recovery rates will vary case by case, depending on factors such as the water parameters and how companies drive their production processes, a model wastewater containing 3kg of organics and 2kg of sodium per m"3 could remove about 0.5kg of the organics, producing 2.5kg of sodium hydroxide and removing 1.44kg of sodium from the waste stream. For a pulp and paper plant, Dr Rabaey reckons 5-10 per cent of the typical organic load could provide all the site's sodium hydroxide demand. Most industries he's studied have more than enough wastewater organics to become self-sufficient in sodium hydroxide. In 2008, he co-founded Bilexys, a spin-off company from the University of Queensland aiming to commercialise the technology for recovery of caustic and, down the track, hydrogen peroxide. Early next year, Bilexys will be building a pilot

Caustic saving potentile in textile processing mills

International Nuclear Information System (INIS)

Latif, M.; Rehman, A.; Ghafar, A.; Hafeez, N.M.

2010-01-01

The textile processing industry of pakistan has great potential of improvement in resource consumption in various production processes. One major concern is the heavy usage of caustic soda (sodium hydroxide) especially during the mercerization process which incurs a significant cost to a textile processing mill. To reduce the unit fabric production cost and stay competitive, the industry need to minimize the caustic wastage and explore the caustic saving potential. This paper describe the detailed caustic consumption practices and saving potentials in woven textile sector based on the data base of 100 industries. Region wise caustic saving potential is also investigated . Three caustic conservation option including process improvement, reuse and recycling, and caustic recovery plants are discussed. Detailed technical and and financial requirements. saving potentials and paybacks of these options are provided. (author)

Space-time caustics

Directory of Open Access Journals (Sweden)

Arthur D. Gorman

1986-01-01

Full Text Available The Lagrange manifold (WKB formalism enables the determination of the asymptotic series solution of linear differential equations modelling wave propagation in spatially inhomogeneous media at caustic (turning points. Here the formalism is adapted to determine a class of asymptotic solutions at caustic points for those equations modelling wave propagation in media with both spatial and temporal inhomogeneities. The analogous Schrodinger equation is also considered.

Predicting soil formation on the basis of transport-limited chemical weathering

Science.gov (United States)

Yu, Fang; Hunt, Allen Gerhard

2018-01-01

Soil production is closely related to chemical weathering. It has been shown that, under the assumption that chemical weathering is limited by solute transport, the process of soil production is predictable. However, solute transport in soil cannot be described by Gaussian transport. In this paper, we propose an approach based on percolation theory describing non-Gaussian transport of solute to predict soil formation (the net production of soil) by considering both soil production from chemical weathering and removal of soil from erosion. Our prediction shows agreement with observed soil depths in the field. Theoretical soil formation rates are also compared with published rates predicted using soil age-profile thickness (SAST) method. Our formulation can be incorporated directly into landscape evolution models on a point-to-point basis as long as such models account for surface water routing associated with overland flow. Further, our treatment can be scaled-up to address complications associated with continental-scale applications, including those from climate change, such as changes in vegetation, or surface flow organization. The ability to predict soil formation rates has implications for understanding Earth's climate system on account of the relationship to chemical weathering of silicate minerals with the associated drawdown of atmospheric carbon, but it is also important in geomorphology for understanding landscape evolution, including for example, the shapes of hillslopes, and the net transport of sediments to sedimentary basins.

Calcium weathering in forested soils and the effedt of different tree species

NARCIS (Netherlands)

Dijkstra, F.A.; Breemen, van N.; Jongmans, A.G.; Davies, G.R.; Likens, G.E.

2003-01-01

Soil weathering can be an important mechanism to neutralize acidity in forest soils. Tree species may differ in their effect on or response to soil weathering. We used soil mineral data and the natural strontium isotope ratio Sr-87/Sr-86 as a tracer to identify the effect of tree species on the Ca

Caustic Skeleton & Cosmic Web

Science.gov (United States)

Feldbrugge, Job; van de Weygaert, Rien; Hidding, Johan; Feldbrugge, Joost

2018-05-01

We present a general formalism for identifying the caustic structure of a dynamically evolving mass distribution, in an arbitrary dimensional space. The identification of caustics in fluids with Hamiltonian dynamics, viewed in Lagrangian space, corresponds to the classification of singularities in Lagrangian catastrophe theory. On the basis of this formalism we develop a theoretical framework for the dynamics of the formation of the cosmic web, and specifically those aspects that characterize its unique nature: its complex topological connectivity and multiscale spinal structure of sheetlike membranes, elongated filaments and compact cluster nodes. Given the collisionless nature of the gravitationally dominant dark matter component in the universe, the presented formalism entails an accurate description of the spatial organization of matter resulting from the gravitationally driven formation of cosmic structure. The present work represents a significant extension of the work by Arnol'd et al. [1], who classified the caustics that develop in one- and two-dimensional systems that evolve according to the Zel'dovich approximation. His seminal work established the defining role of emerging singularities in the formation of nonlinear structures in the universe. At the transition from the linear to nonlinear structure evolution, the first complex features emerge at locations where different fluid elements cross to establish multistream regions. Involving a complex folding of the 6-D sheetlike phase-space distribution, it manifests itself in the appearance of infinite density caustic features. The classification and characterization of these mass element foldings can be encapsulated in caustic conditions on the eigenvalue and eigenvector fields of the deformation tensor field. In this study we introduce an alternative and transparent proof for Lagrangian catastrophe theory. This facilitates the derivation of the caustic conditions for general Lagrangian fluids, with

Direct soil contact values for ecological receptors exposed to weathered petroleum hydrocarbon (PHC) fraction 2.

Science.gov (United States)

Angell, Robin A; Kullman, Steve; Shrive, Emma; Stephenson, Gladys L; Tindal, Miles

2012-11-01

Ecological tier 1 Canada-wide standards (CWS) for petroleum hydrocarbon (PHC) fraction 2 (F2; >nC10-C16) in soil were derived using ecotoxicological assessment endpoints (effective concentrations [ECs]/lethal concentrations [LCs]/inhibitory concentrations, 25% [IC25s]) with freshly spiked (fresh) fine- and coarse-grained soils. These soil standards might be needlessly conservative when applied to field samples with weathered hydrocarbons. The purpose of the present study was to assess the degradation and toxicity of weathered PHC F2 in a fine-grained soil and to derive direct soil contact values for ecological receptors. Fine-grained reference soils were spiked with distilled F2 and weathered for 183 d. Toxicity tests using plants and invertebrates were conducted with the weathered F2-spiked soils. Endpoint EC/IC25s were calculated and used to derive soil standards for weathered F2 in fine-grained soil protective of ecological receptors exposed via direct soil contact. The values derived for weathered F2 were less restrictive than current ecological tier 1 CWS for F2 in soil. Copyright © 2012 SETAC.

Caustic Ingestions

Directory of Open Access Journals (Sweden)

M Rafeey

2014-04-01

Full Text Available Prevention has a main role in reducing the occurrence of corrosive ingestion especially in children, yet this goal is far from being reached in developing countries, where such injuries are largely unreported and their true prevalence simply cannot be extrapolated from random articles or personal experience. Because of the accidental nature of the ingestions, the case fatality rate for pediatric patients is significantly less than that of adolescents and adults.  Currently, esophagoscopy is recommended for all patients with a history of caustic substance ingestion because clinical criteria have not proved to be reliable predictors of esophageal injury. The presence or absence of three serious signs and symptoms-vomiting, drooling, and stridor—as well as the presence and location of oropharyngeal burns could be  compared with the findings on subsequent esophagoscopy. Medical or endoscopic prevention of stricture is debatable, yet esophageal stents, absorbable or not, show promising data. The purpose of this lecture is to outline the current epidemiology, mechanism of injury, clinical manifestations, management and long-term complications of caustic ingestions in pediatric patients.   Key Words: Caustic, Children, Ingestions.

Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

Science.gov (United States)

Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

2013-01-01

Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

Tunable caustic phenomena in electron wavefields

Energy Technology Data Exchange (ETDEWEB)

Tavabi, Amir Hossein, E-mail: a.tavabi@fz-juelich.de [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Migunov, Vadim; Dwyer, Christian; Dunin-Borkowski, Rafal E. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Pozzi, Giulio [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute (PGI), Forschungszentrum Jülich, D-52425 Jülich (Germany); Department of Physics and Astronomy, University of Bologna, Viale B. Pichat 6/2, 40127 Bologna (Italy)

2015-10-15

Novel caustic phenomena, which contain fold, butterfly and elliptic umbilic catastrophes, are observed in defocused images of two approximately collinear oppositely biased metallic tips in a transmission electron microscope. The observed patterns depend sensitively on defocus, on the applied voltage between the tips and on their separation and lateral offset. Their main features are interpreted on the basis of a projected electrostatic potential model for the electron-optical phase shift. - Highlights: • Electron-optical caustics are observed in defocused images of biased metallic tips. • The caustics depend on defocus, on the bias between the tips and on their separation. • The setup offers the flexibility to study a wide variety of caustic phenomena.

Spatial Prediction of Soil Classes by Using Soil Weathering Parameters Derived from vis-NIR Spectroscopy

Science.gov (United States)

Ramirez-Lopez, Leonardo; Alexandre Dematte, Jose

2010-05-01

There is consensus in the scientific community about the great need of spatial soil information. Conventional mapping methods are time consuming and involve high costs. Digital soil mapping has emerged as an area in which the soil mapping is optimized by the application of mathematical and statistical approaches, as well as the application of expert knowledge in pedology. In this sense, the objective of the study was to develop a methodology for the spatial prediction of soil classes by using soil spectroscopy methodologies related with fieldwork, spectral data from satellite image and terrain attributes in simultaneous. The studied area is located in São Paulo State, and comprised an area of 473 ha, which was covered by a regular grid (100 x 100 m). In each grid node was collected soil samples at two depths (layers A and B). There were extracted 206 samples from transect sections and submitted to soil analysis (clay, Al2O3, Fe2O3, SiO2 TiO2, and weathering index). The first analog soil class map (ASC-N) contains only soil information regarding from orders to subgroups of the USDA Soil Taxonomy System. The second (ASC-H) map contains some additional information related to some soil attributes like color, ferric levels and base sum. For the elaboration of the digital soil maps the data was divided into three groups: i) Predicted soil attributes of the layer B (related to the soil weathering) which were obtained by using a local soil spectral library; ii) Spectral bands data extracted from a Landsat image; and iii) Terrain parameters. This information was summarized by a principal component analysis (PCA) in each group. Digital soil maps were generated by supervised classification using a maximum likelihood method. The trainee information for this classification was extracted from five toposequences based on the analog soil class maps. The spectral models of weathering soil attributes shown a high predictive performance with low error (R2 0.71 to 0.90). The spatial

Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

International Nuclear Information System (INIS)

Doll, Stephanie R.; Bolling, Stacie D.

2016-01-01

Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarized light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, ''Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.'' The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.

Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

Energy Technology Data Exchange (ETDEWEB)

Doll, Stephanie R. [Washington River Protection Solutions, Richland, WA (United States); Bolling, Stacie D. [Washington River Protection Solutions, Richland, WA (United States)

2016-07-14

Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarized light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, “Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.” The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.

Sorption of Cu and Zn in low organic matter-soils as influenced by soil properties and by the degree of soil weathering.

Science.gov (United States)

Antoniadis, V; Golia, E E

2015-11-01

Copper and Zn sorption and desorption, among other factors, depend on soil pH, but in soils with different degree of weathering the role of other soil properties (e.g., oxides content and the level of their crystallinity) has not been thoroughly examined. We conducted batch sorption and desorption tests using 21 low-organic C soils that belonged to the soil orders of Entisols, newly developed soils, Inceptisols, and Alfisols, the most weathered soils. Zinc sorption was lower than that of Cu, and its desorption faster, confirming that it is a highly mobile metal. Alfisols had the weaker affinity for metals, due to the lower soil pH typical of this soil order, but also due to the low reactivity colloids they contained. Correlation analyses showed that Fe oxides in Alfisols increased metal release from soils, while they decreased metal desorption from Entisols. We conclude that in low organic matter-content soils, where the protective role of organic colloids is not to be expected, high soil pH alone is not sufficient to protect against metal contamination, but the degree of soil weathering is also important, due to the dominant role of other mineral phases (here, Fe oxides). Copyright © 2015 Elsevier Ltd. All rights reserved.

Extraction, scrub, and strip test results for the salt waste processing facility caustic side solvent extraction solvent example

Energy Technology Data Exchange (ETDEWEB)

Peters, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-08-01

An Extraction, Scrub, and Strip (ESS) test was performed on a sample of Salt Waste Processing Facility (SWPF) Caustic-Side Solvent Extraction (CSSX) solvent and salt simulant to determine cesium distribution ratios (D(Cs)), and cesium concentration in the strip effluent (SE) and decontaminated salt solution (DSS) streams; this data will be used by Parsons to help determine if the solvent is qualified for use at the SWPF. The ESS test showed acceptable performance of the solvent for extraction, scrub, and strip operations. The extraction D(Cs) measured 12.9, exceeding the required value of 8. This value is consistent with results from previous ESS tests using similar solvent formulations. Similarly, scrub and strip cesium distribution ratios fell within acceptable ranges.

Biogeochemical weathering of serpentinites: An examination of incipient dissolution affecting serpentine soil formation

International Nuclear Information System (INIS)

Baumeister, Julie L.; Hausrath, Elisabeth M.; Olsen, Amanda A.; Tschauner, Oliver; Adcock, Christopher T.; Metcalf, Rodney V.

2015-01-01

Highlights: • Dissolution of primary minerals is important to porosity generation in serpentinites. • Mineral weathering extent in serpentinites follows the order Fe > Mg > Al rich minerals. • Fe-oxidizing bacteria may mediate Fe-rich primary and serpentine mineral alteration. • Serpentinite weathering is strongly impacted by degree of serpentinization. - Abstract: Serpentinite rocks, high in Mg and trace elements including Ni, Cr, Cd, Co, Cu, and Mn and low in nutrients such as Ca, K, and P, form serpentine soils with similar chemical properties resulting in chemically extreme environments for the biota that grow upon them. The impact of parent material on soil characteristics is most important in young soils, and therefore the incipient weathering of serpentinite rock likely has a strong effect on the development of serpentine soils and ecosystems. Additionally, porosity generation is a crucial process in converting rock into a soil that can support vegetation. Here, the important factors affecting the incipient weathering of serpentinite rock are examined at two sites in the Klamath Mountains, California. Serpentinite-derived soils and serpentinite rock cores were collected in depth profiles from each sampling location. Mineral dissolution in weathered serpentinite samples, determined by scanning electron microscopy, energy dispersive spectrometry, electron microprobe analyses, and synchrotron microXRD, is consistent with the order, from most weathered to least weathered: Fe-rich pyroxene > antigorite > Mg-rich lizardite > Al-rich lizardite. These results suggest that the initial porosity formation within serpentinite rock, impacting the formation of serpentine soil on which vegetation can exist, is strongly affected both by the presence of non-serpentine primary minerals as well as the composition of the serpentine minerals. In particular, the presence of ferrous Fe appears to contribute to greater dissolution, whereas the presence of Al within the

Climate-change effects on soils: Accelerated weathering, soil carbon and elemental cycling

Energy Technology Data Exchange (ETDEWEB)

Qafoku, Nikolla

2015-04-01

Climate change [i.e., high atmospheric carbon dioxide (CO2) concentrations (≥400 ppm); increasing air temperatures (2-4°C or greater); significant and/or abrupt changes in daily, seasonal, and inter-annual temperature; changes in the wet/dry cycles; intensive rainfall and/or heavy storms; extended periods of drought; extreme frost; heat waves and increased fire frequency] is and will significantly affect soil properties and fertility, water resources, food quantity and quality, and environmental quality. Biotic processes that consume atmospheric CO2, and create organic carbon (C) that is either reprocessed to CO2 or stored in soils are the subject of active current investigations, with great concern over the influence of climate change. In addition, abiotic C cycling and its influence on the inorganic C pool in soils is a fundamental global process in which acidic atmospheric CO2 participates in the weathering of carbonate and silicate minerals, ultimately delivering bicarbonate and Ca2+ or other cations that precipitate in the form of carbonates in soils or are transported to the rivers, lakes, and oceans. Soil responses to climate change will be complex, and there are many uncertainties and unresolved issues. The objective of the review is to initiate and further stimulate a discussion about some important and challenging aspects of climate-change effects on soils, such as accelerated weathering of soil minerals and resulting C and elemental fluxes in and out of soils, soil/geo-engineering methods used to increase C sequestration in soils, soil organic matter (SOM) protection, transformation and mineralization, and SOM temperature sensitivity. This review reports recent discoveries, identifies key research needs, and highlights opportunities offered by the climate-change effects on soils.

Characterisation of weathered clayey soils responsible for shallow landslides

Directory of Open Access Journals (Sweden)

C. Meisina

2006-01-01

Full Text Available Shallow earth translational slides and earth flows, affecting colluvial soils derived by the weathering of the clayey bedrock, are a recurrent problem causing damage to buildings and roads in many areas of Apennines. The susceptibility assessment, e.g. slope stability models, requires the preliminary characterization of these superficial covers (lithology, geotechnical and hydraulic parameters. The aim of the work is to develop and test a methodology for the identification and mapping of weathered clayey soils responsible for shallow landslides. A test site in Northern Apennines (Province of Pavia was selected. Argillaceous and marly successions characterize the area. Shallow landslides occurred periodically due to high intensity rainfalls. Trench pits were used for the soil profile description (lithology, structure, grade of weathering, thickness and sampling. The main geological, topographic and geomorphologic parameters of shallow landslides were analysed. Field surveys were integrated with some geotechnical laboratory tests (index properties, suction and volumetric characteristic determination, methylene blue adsorption test, linear shrinkage, swell strain. Engineering geological zoning was carried out by grouping the superficial soils on the basis of the following attributes: topographic conditions (slope angle, landslide occurrence, lithology (grain size, geometry (thickness, lithology of the bedrock, hydrogeological and geotechnical characteristics. The resulting engineering-geological units (areas that may be regarded as homogeneous from the geomorphologic and engineering – geological point of view were analysed in terms of shallow slope instability.

Washing and caustic leaching of Hanford tank sludges

International Nuclear Information System (INIS)

Lumetta, G.J.; Rapko, B.M.; Colton, N.G.

1994-01-01

Methods are being developed to treat and dispose of large volumes of radioactive wastes stored in underground tanks at the U.S. Department of Energy's Hanford Site. The wastes will be partitioned into high-level waste (HLW) and low-level waste (LLW) fractions. The HLW will be vitrified into borosilicate glass and disposed of in a geologic repository, while the LLW will be immobilized in a glass matrix and will likely be disposed of by shallow burial at the Hanford Site. The wastes must be pretreated to reduce the volume of the HLW fraction, so that vitrification and disposal costs can be minimized. The current baseline process for pretreating Hanford tank sludges is to leach the sludge under caustic conditions, then remove the solubilized components of the sludge by water washing. Tests of this method have been performed with samples taken from several different tanks at Hanford. The results of these tests are presented in terms of the composition of the sludge before and after leaching. X-ray diffraction and scanning electron microscopy coupled with electron dispersive x-ray techniques have been used to identify the phases in the untreated and treated sludges

Crude oil degradation potential of bacteria isolated from oil-polluted soil and animal wastes in soil amended with animal wastes

Directory of Open Access Journals (Sweden)

Voke O. Urhibo

2017-03-01

Full Text Available The influence of animal wastes on crude oil degradation potential of strains of Proteus vulgaris and Bacillus subtilis isolated from animal wastes (poultry and pig droppings and petroleum-polluted soil was compared in laboratory studies. Both bacterial strains were selected for high crude oil degradation ability after screening many isolates by the 2,6-dichlorophenol indophenol method. Analyses by gas chromatography (GC showed that degradation of crude oil was markedly enhanced (88.3–97.3% vs 72.1–78.8% in soil amended with animal wastes as indicated by the reduction of total petroleum hydrocarbon (TPH. TPH reduction by animal waste bacterial strains in animal waste-amended soil was more than the reduction by strains from soil contaminated with petroleum (P < 0.001. The greatest reduction of TPH (96.6–97.3% vs 80.4–95.9% was by poultry waste strains and it occurred in soil amended with poultry waste. GC analyses of n-alkanes showed that although shorter chains were preferentially degraded [32.0–78.5% (C8–23 vs 6.3–18.5% (C24–36] in normal soil, biodegradation of longer chains increased to 38.4–46.3% in animal waste-amended soil inoculated with the same animal wastes’ strains. The results indicate that these animal waste strains may be of potential application for bioremediation of oil-polluted soil in the presence of the wastes from where they were isolated.

Device for processing regenerative wastes of ion exchange resin

International Nuclear Information System (INIS)

Kuroda, Osamu; Ebara, Katsuya; Shindo, Toshikazu; Takahashi, Sankichi

1986-01-01

Purpose: To facilitate the operation and maintenance of a processing device by dividing radioactive wastes produced in the regenerative process of ion exchange resin into a regenerated usable recovery liquid and wastes. Constitution: Sulfuric acid is recovered by a diffusion dialysis method from wastes containing sulfuric acid that are generated in the regenerative process of cation-exchange resin and also caustic soda is recovered by the diffusion dialysis method from wastes containing caustic soda that are generated in the regenerative process of anion-exchange resin. The sulfuric acid and caustic soda thus recovered are used for the regeneration of ion-exchange resin. A concentrator is provided for concentrating the sulfuric acid and caustic soda water solution to concentration suitable for the regeneration of these ion-exchange resins. Also provided is a recovery device for recovering water generated from the concentrator. This device is of so simple a constitution that its operation and maintenance can be performed very easily, thereby greatly reducing the quantity of waste liquid required to be stored in drums. (Takahashi, M.)

Biochar from sugarcane filtercake reduces soil CO2 emissions relative to raw residue and improves water retention and nutrient availability in a highly-weathered tropical soil.

Science.gov (United States)

Eykelbosh, Angela Joy; Johnson, Mark S; Santos de Queiroz, Edmar; Dalmagro, Higo José; Guimarães Couto, Eduardo

2014-01-01

In Brazil, the degradation of nutrient-poor Ferralsols limits productivity and drives agricultural expansion into pristine areas. However, returning agricultural residues to the soil in a stabilized form may offer opportunities for maintaining or improving soil quality, even under conditions that typically promote carbon loss. We examined the use of biochar made from filtercake (a byproduct of sugarcane processing) on the physicochemical properties of a cultivated tropical soil. Filtercake was pyrolyzed at 575°C for 3 h yielding a biochar with increased surface area and porosity compared to the raw filtercake. Filtercake biochar was primarily composed of aromatic carbon, with some residual cellulose and hemicellulose. In a three-week laboratory incubation, CO2 effluxes from a highly weathered Ferralsol soil amended with 5% biochar (dry weight, d.w.) were roughly four-fold higher than the soil-only control, but 23-fold lower than CO2 effluxes from soil amended with 5% (d.w.) raw filtercake. We also applied vinasse, a carbon-rich liquid waste from bioethanol production typically utilized as a fertilizer on sugarcane soils, to filtercake- and biochar-amended soils. Total CO2 efflux from the biochar-amended soil in response to vinasse application was only 5% of the efflux when vinasse was applied to soil amended with raw filtercake. Furthermore, mixtures of 5 or 10% biochar (d.w.) in this highly weathered tropical soil significantly increased water retention within the plant-available range and also improved nutrient availability. Accordingly, application of sugarcane filtercake as biochar, with or without vinasse application, may better satisfy soil management objectives than filtercake applied to soils in its raw form, and may help to build soil carbon stocks in sugarcane-cultivating regions.

Biochar from Sugarcane Filtercake Reduces Soil CO2 Emissions Relative to Raw Residue and Improves Water Retention and Nutrient Availability in a Highly-Weathered Tropical Soil

Science.gov (United States)

Eykelbosh, Angela Joy; Johnson, Mark S.; Santos de Queiroz, Edmar; Dalmagro, Higo José; Guimarães Couto, Eduardo

2014-01-01

In Brazil, the degradation of nutrient-poor Ferralsols limits productivity and drives agricultural expansion into pristine areas. However, returning agricultural residues to the soil in a stabilized form may offer opportunities for maintaining or improving soil quality, even under conditions that typically promote carbon loss. We examined the use of biochar made from filtercake (a byproduct of sugarcane processing) on the physicochemical properties of a cultivated tropical soil. Filtercake was pyrolyzed at 575°C for 3 h yielding a biochar with increased surface area and porosity compared to the raw filtercake. Filtercake biochar was primarily composed of aromatic carbon, with some residual cellulose and hemicellulose. In a three-week laboratory incubation, CO2 effluxes from a highly weathered Ferralsol soil amended with 5% biochar (dry weight, d.w.) were roughly four-fold higher than the soil-only control, but 23-fold lower than CO2 effluxes from soil amended with 5% (d.w.) raw filtercake. We also applied vinasse, a carbon-rich liquid waste from bioethanol production typically utilized as a fertilizer on sugarcane soils, to filtercake- and biochar-amended soils. Total CO2 efflux from the biochar-amended soil in response to vinasse application was only 5% of the efflux when vinasse was applied to soil amended with raw filtercake. Furthermore, mixtures of 5 or 10% biochar (d.w.) in this highly weathered tropical soil significantly increased water retention within the plant-available range and also improved nutrient availability. Accordingly, application of sugarcane filtercake as biochar, with or without vinasse application, may better satisfy soil management objectives than filtercake applied to soils in its raw form, and may help to build soil carbon stocks in sugarcane-cultivating regions. PMID:24897522

Biochar from sugarcane filtercake reduces soil CO2 emissions relative to raw residue and improves water retention and nutrient availability in a highly-weathered tropical soil.

Directory of Open Access Journals (Sweden)

Angela Joy Eykelbosh

Full Text Available In Brazil, the degradation of nutrient-poor Ferralsols limits productivity and drives agricultural expansion into pristine areas. However, returning agricultural residues to the soil in a stabilized form may offer opportunities for maintaining or improving soil quality, even under conditions that typically promote carbon loss. We examined the use of biochar made from filtercake (a byproduct of sugarcane processing on the physicochemical properties of a cultivated tropical soil. Filtercake was pyrolyzed at 575°C for 3 h yielding a biochar with increased surface area and porosity compared to the raw filtercake. Filtercake biochar was primarily composed of aromatic carbon, with some residual cellulose and hemicellulose. In a three-week laboratory incubation, CO2 effluxes from a highly weathered Ferralsol soil amended with 5% biochar (dry weight, d.w. were roughly four-fold higher than the soil-only control, but 23-fold lower than CO2 effluxes from soil amended with 5% (d.w. raw filtercake. We also applied vinasse, a carbon-rich liquid waste from bioethanol production typically utilized as a fertilizer on sugarcane soils, to filtercake- and biochar-amended soils. Total CO2 efflux from the biochar-amended soil in response to vinasse application was only 5% of the efflux when vinasse was applied to soil amended with raw filtercake. Furthermore, mixtures of 5 or 10% biochar (d.w. in this highly weathered tropical soil significantly increased water retention within the plant-available range and also improved nutrient availability. Accordingly, application of sugarcane filtercake as biochar, with or without vinasse application, may better satisfy soil management objectives than filtercake applied to soils in its raw form, and may help to build soil carbon stocks in sugarcane-cultivating regions.

Interactions of low-level, liquid radioactive wastes with soils. 1. Behavior of radionuclides in soil-waste systems

International Nuclear Information System (INIS)

Fowler, E.B.; Essington, E.H.; Polzer, W.L.

1981-01-01

The characteristics of radioactive wastes and soils vary over a wide range. Liquid radioactive waste entering the environment will eventually contact the soil or geological matrix; interactions will be determined by the chemical and physical nature of the liquid, as well as the soil matrix. We report here the results from an investigation of certain of those characteristics as they relate to retention of radionuclides by soils. Three fractions were demonstrated in the waste as filterable, soluble-sorbable, and soluble-nonsorbable; the physical nature of each fraction was demonstrated using autoradiographic techniques. Isotopes of plutonium and uranium and americium-241 in the soluble fraction of the waste were shown to have a negative charge as determined by ion exchange techniques. In the soil-waste systems, the net charge for those radionuclides was shown to change from predominantly negative to predominantly positive. Nevertheless, cesium-137 was shown to be predominantly positited by TVA and approved by NRC (formerly AEC) since June 1973. This report is based upon the revisions, approved through the end of this reporting period

Improving soil enzyme activities and related quality properties of reclaimed soil by applying weathered coal in opencast-mining areas of the Chinese loess plateau

Energy Technology Data Exchange (ETDEWEB)

Li, Hua [College of Environment and Resources, Shanxi University, Taiyuan (China); CAS/Shandong Provincial Key Laboratory of Coastal Environmental Process, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences (CAS), Yantai (China); Shao, Hongbo [CAS/Shandong Provincial Key Laboratory of Coastal Environmental Process, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences (CAS), Yantai (China); Institute for Life Sciences, Qingdao University of Science and Technology (QUST), Qingdao (China); Li, Weixiang; Bi, Rutian [Shanxi Agricultural University, Taigu (China); Bai, Zhongke [Department of Land Science Technology, University of Geosciences, Beijing (China)

2012-03-15

There are many problems for the reclaimed soil in opencast-mining areas of the Loess Plateau of China such as poor soil structure and extreme poverty in soil nutrients and so on. For the sake of finding a better way to improve soil quality, the current study was to apply the weathered coal for repairing soil media and investigate the physicochemical properties of the reclaimed soil and the changes in enzyme activities after planting Robinia pseucdoacacia. The results showed that the application of the weathered coal significantly improved the quality of soil aggregates, increased the content of water stable aggregates, and the organic matter, humus, and the cation exchange capacity of topsoil were significantly improved, but it did not have a significant effect on soil pH. Planting R. pseucdoacacia significantly enhanced the activities of soil catalase, urease, and invertase, but the application of the weathered coal inhibited the activity of catalase. Although the application of appropriate weathered coal was able to significantly increase urease activity, the activities of catalase, urease, or invertase had a close link with the soil profile levels and time. This study suggests that applying weathered coals could improve the physicochemical properties and soil enzyme activities of the reclaimed soil in opencast-mining areas of the Loess Plateau of China and the optimum applied amount of the weathered coal for reclaimed soil remediation is about 27 000 kg hm{sup -2}. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Weathering and genesis of Soils from Ellsworth Mountains, East Antarctica

Science.gov (United States)

Karoline Delpupo Souza, Katia; Schaefer, Carlos Ernesto; Michel, Roberto; Monari, Julia; Machado, Vania

2015-04-01

Knowledge on Antarctic soils from the Ellsworth Mountains (EM) are patchy comparatively with Dry Valleys soils from the Transantartic Mountains, and could help understand the genesis of cryogenic soils under extreme dry, cold desert conditions. The EM are a slightly arcuate 350-km-long north-northwest-trending mountain chain is bordered on the west by the polar plateau of West Antarctica and on the east by Ronne Ice Shelf. The range is as much as 90 km wide and constitutes one of the largest areas of exposed bedrock in West Antarctica. The stratigraphic succession in the EM includes strata from Cambriam to Permian in age. The objective of this study is to analyze the properties of soils from EM in order to identify the main factors and processes involved in soil formation under cold desert conditions in Antarctica. The sampling design aimed to represent the different geological substrates (marble-clast conglomerate, graywacke, argillite, conglomerate, black shale, marble and quartzite) as well as altitudinal levels and landforms within the same substrate. We characterized soils from EM regarding their morphological, physics and chemical properties. Soil samples were air dried and passed through 2 mm sieves. After removal of water soluble salts, the samples were submitted to chemical and physical analyses such as: pH in water, potential acidity (H + Al), exchangeable bases, total organic carbon, electric conductivity, soil texture and color. The soils classify, for the most part, in weathering stages 1 to 2. Only in the upper parts of ridges were there traces of soils at weathering stage 3. This indicates that much of the present icefree topography has been overridden by ice within the last few hundred thousand years. Cryoturbation is a widespread phenomenon in this area resulting in intense cryoclastic weathering and patterned ground, forming sorted circles, stripes and gelifluxion lobes. The soil show low horizontation, discrete patches of salt on the surface, and

Quantifying Heterogeneities in Soil Cover and Weathering in the Bitterroot and Sapphire Mountains, Montana: Implications for Glacial Legacies and their Morphologic Control on Soil Formation

Science.gov (United States)

Benjaram, S. S.; Dixon, J. L.

2017-12-01

To what extent is chemical weathering governed by a landscape's topography? Quantifying chemical weathering in both steep rocky landscapes and soil-mantled landscapes requires describing heterogeneity in soil and rock cover at local and landscape scales. Two neighboring mountain ranges in the northern Rockies of western Montana, USA, provide an ideal natural laboratory in which to investigate the relationship between soil chemical weathering, persistence of soil cover, and topography. We focus our work in the previously glaciated Bitterroot Mountains, which consist of steep, rock-dominated hillslopes, and the neighboring unglaciated Sapphire Mountains, which display convex, soil-mantled hillslopes. Soil thickness measurements, soil and rock geochemistry, and digital terrain analysis reveal that soils in the rock-dominated Bitterroot Mountains are only slightly less weathered than those in the Sapphire Mountains. However, these differences are magnified when adjusted for rock fragments at a local scale and bedrock cover at a landscape scale, using our newly developed metric, the rock-adjusted chemical depletion fraction (RACDF) and rock-adjusted mass transfer coefficient (RA τ). The Bitterroots overall are 30% less weathered than the Sapphires despite higher mean annual precipitation in the former, with an average rock-adjusted CDF of 0.38 in the postglacial Bitterroots catchment and 0.61 in the nonglacial Sapphire catchment, suggesting that 38% of rock mass is lost in the conversion to soil in the Bitterroots, whereas 61% of rock mass is lost in the nonglaciated Sapphires. Because the previously glaciated Bitterroots are less weathered despite being wetter, we conclude that the glacial history of this landscape exerts more influence on soil chemical weathering than does modern climate. However, while previous studies have correlated weathering intensity with topographic parameters such as slope gradient, we find little topographic indication of specific controls

Ingestion of caustic substances and its complications

Directory of Open Access Journals (Sweden)

Rui Celso Martins Mamede

2001-01-01

Full Text Available CONTEXT: Caustic substances cause tissue destruction through liquefaction or coagulation reactions and the intensity of destruction depends on the type, concentration, time of contact and amount of the substance ingested. OBJECTIVES: To analyze the complications in patients who ingested caustic substances and correlate them with the amount of caustic soda ingested. DESIGN: Retrospective study. SETTING: University hospital, a referral center. PARTICIPANTS: A total of 239 patients who ingested caustic soda. MAIN MEASUREMENTS: The amount of granulated caustic substance ingested was measured as tablespoonfuls and the following complications were analyzed: esophagitis, esophageal stenosis and progression to cancer, fistulas, perforations, stomach lesions, brain abscesses, and death. Stenosis was classified as mild, moderate or severe according to the radiological findings. RESULTS: We observed an 89.3% incidence of esophagitis; 72.6% of the cases involved progression to stenosis and 1% died during the acute phase. Stenosis was mild in 17.6% of cases, moderate in 59.3% and severe in 23%. The incidence of stenosis was 80.8% in women and 62.5% in men. The incidence of stenosis was 46.9% in the group that ingested "fragments" and 93.6% in the group that ingested one or more tablespoonfuls of caustic substances. Among subjects who ingested one or more tablespoonfuls, 32.2% developed lesions of the stomach-duodenum, whereas the ingestion of "fragments" was not sufficient to induce these lesions. There was no correlation between the intensity of lesions of the esophagus and of the stomach. Progression to cancer of the esophagus occurred in 1.8% of cases, death during the chronic phase in 1.4%, perforations in 4.6%, fistulas in 0.9%, and brain abscesses in 1.4%. CONCLUSIONS: The complications were related to the amount of caustic soda ingested. Small amounts caused esophagitis or stenosis and large amounts increased the risk of fistulas, perforations and

Chemical evolution of leaked high-level liquid wastes in Hanford soils

Energy Technology Data Exchange (ETDEWEB)

NYMAN,MAY D.; KRUMHANSL,JAMES L.; ZHANG,PENGCHU; ANDERSON,HOWARD L.; NENOFF,TINA M.

2000-05-19

A number of Hanford tanks have leaked high level radioactive wastes (HLW) into the surrounding unconsolidated sediments. The disequilibrium between atmospheric C0{sub 2} or silica-rich soils and the highly caustic (pH > 13) fluids is a driving force for numerous reactions. Hazardous dissolved components such as {sup 133}Cs, {sup 79}Se, {sup 99}Tc may be adsorbed or sequestered by alteration phases, or released in the vadose zone for further transport by surface water. Additionally, it is likely that precipitation and alteration reactions will change the soil permeability and consequently the fluid flow path in the sediments. In order to ascertain the location and mobility/immobility of the radionuclides from leaked solutions within the vadose zone, the authors are currently studying the chemical reactions between: (1) tank simulant solutions and Hanford soil fill minerals; and (2) tank simulant solutions and C0{sub 2}. The authors are investigating soil-solution reactions at: (1) elevated temperatures (60--200 C) to simulate reactions which occur immediately adjacent a radiogenically heated tank; and (2) ambient temperature (25 C) to simulate reactions which take place further from the tanks. The authors studies show that reactions at elevated temperature result in dissolution of silicate minerals and precipitation of zeolitic phases. At 25 C, silicate dissolution is not significant except where smectite clays are involved. However, at this temperature CO{sub 2} uptake by the solution results in precipitation of Al(OH){sub 3} (bayerite). In these studies, radionuclide analogues (Cs, Se and Re--for Tc) were partially removed from the test solutions both during high-temperature fluid-soil interactions and during room temperature bayerite precipitation. Altered soils would permanently retain a fraction of the Cs but essentially all of the Se and Re would be released once the plume was past and normal groundwater came in contact with the contaminated soil. Bayerite

Chemical evolution of leaked high-level liquid wastes in Hanford soils

International Nuclear Information System (INIS)

NYMAN, MAY D.; KRUMHANSL, JAMES L.; ZHANG, PENGCHU; ANDERSON, HOWARD L.; NENOFF, TINA M.

2000-01-01

A number of Hanford tanks have leaked high level radioactive wastes (HLW) into the surrounding unconsolidated sediments. The disequilibrium between atmospheric C0 2 or silica-rich soils and the highly caustic (pH > 13) fluids is a driving force for numerous reactions. Hazardous dissolved components such as 133 Cs, 79 Se, 99 Tc may be adsorbed or sequestered by alteration phases, or released in the vadose zone for further transport by surface water. Additionally, it is likely that precipitation and alteration reactions will change the soil permeability and consequently the fluid flow path in the sediments. In order to ascertain the location and mobility/immobility of the radionuclides from leaked solutions within the vadose zone, the authors are currently studying the chemical reactions between: (1) tank simulant solutions and Hanford soil fill minerals; and (2) tank simulant solutions and C0 2 . The authors are investigating soil-solution reactions at: (1) elevated temperatures (60--200 C) to simulate reactions which occur immediately adjacent a radiogenically heated tank; and (2) ambient temperature (25 C) to simulate reactions which take place further from the tanks. The authors studies show that reactions at elevated temperature result in dissolution of silicate minerals and precipitation of zeolitic phases. At 25 C, silicate dissolution is not significant except where smectite clays are involved. However, at this temperature CO 2 uptake by the solution results in precipitation of Al(OH) 3 (bayerite). In these studies, radionuclide analogues (Cs, Se and Re--for Tc) were partially removed from the test solutions both during high-temperature fluid-soil interactions and during room temperature bayerite precipitation. Altered soils would permanently retain a fraction of the Cs but essentially all of the Se and Re would be released once the plume was past and normal groundwater came in contact with the contaminated soil. Bayerite, however, will retain significant

Caustic cracking of 2 1/4 CrMo steel

International Nuclear Information System (INIS)

Cowen, H.C.; Thorley, A.W.

1983-12-01

Stress corrosion cracking tests performed on the 21/4 Cr Mo ferritic steel are described. The principal environments studied were strong, aqueous caustic soda, molten anhydrous caustic soda, and caustic soda with an addition of sodium. Emphasis has been placed on material in the quenched-hardened condition. (author)

Impact of hydrocarbon type, concentration and weathering on its biodegradability in soil.

Science.gov (United States)

Maletić, Snežana P; Dalmacija, Božo D; Rončević, Srđan D; Agbaba, Jasmina R; Perović, Svetlana D Ugarčina

2011-01-01

The objective of this research was to investigate the impact of the hydrocarbon type and concentration, as well as the total effect of the natural weathering process to hydrocarbon biodegradability in sandy soil and the environment. In this experiment, sandy soil was separately contaminated with 0.5%, 1.0%, 2.0% and 3.5% of diesel and crude oils. Oil contaminated soil was taken from the Oil Refinery dumping sites after 9 years of weathering, and its concentration was adjusted to the above-mentioned levels. The biodegradation process was monitored by measuring CO(2), evolution rate, hydrocarbon degradation rate and dehydrogenase activity. The favourable concentration ranges for the soil contaminated with diesel oil were 1.0%, with concentrations at about 2.0% causing slightly adverse effects to CO(2) production which was overcome after 2 weeks, and with 3.5% diesel oil causing significant toxicity. For soil contaminated with crude oil, 2.0% was found to be optimum for effective biodegradation, with 3.5% crude oil also causing adverse effects to CO(2) production, although less so than the same concentration of diesel oil. No adverse effect was obtained for any concentration of the weathered oil, as after the weathering process, the remaining contaminants in the soil were mostly poorly degradable constituents like asphaltenes, resins etc. It has been proposed that such residual material from oil degradation is analogous to, and can even be regarded as, humic material. Due to its inert characteristics, insolubility and similarity to humic materials it is unlikely to be environmentally hazardous.

Weathering Effect on {sup 99}Tc Leachability from Cementitious Waste Form

Energy Technology Data Exchange (ETDEWEB)

Um, Wooyong [Pohang Univ. of Science and Technology, Pohang (Korea, Republic of)

2012-07-01

The mass transfer of contaminants from the solid phase to the waste form pore water, and subsequently out of the solid waste form, is directly related to the number and size distribution of pores as well as the microstructure of the waste form. Because permeability and porosity are controlled by pore aperture size, pore volume, and pore distribution, it is important to have some indication of how these characteristics change in the waste form during weathering. Knowledge of changes in these key parameters can be used to develop predictive models that estimate diffusivity or permeability of radioactive contaminants can be used to develop predictive models that estimate diffusivity or permeability of radioactive contaminants from waste forms for long-term performance assessment. It is known that dissolution or precipitation of amorphous/crystalline phases within waste forms alters their pore structure and controls the transport of contaminants our of waste forms. One very important precipitate is calcite, which is formed as a result of carbonation reactions in cement and other high-alkalinity waste forms. Enhanced oxidation can also increase Tc leachability from the waste form. To account for these changes, weathering experiments were conducted in advance to increase our understating of the long-term Tc leachability, especially out of the cementitious waste form. Pore structure analysis was characterized using both N{sub 2} absorption analysis and XMT techniques, and the results show that cementitious waste form is a relatively highly-porous material compared to other waste forms studied in this task, Detailed characterization of Cast Stone chunks and monolith specimens indicate that carbonation reactions can change the Cast Stone pore structure, which in turn may correlate with Tc leachability. Short carbonation reaction times for the Cast Stone causes pore volume and surface area increases, while the average pore diameter decreases. Based on the changes in pore

Pedogenesis, geochemical forms of heavy metals, and artifact weathering in an urban soil chronosequence, Detroit, Michigan

Energy Technology Data Exchange (ETDEWEB)

Howard, Jeffrey L., E-mail: jhoward@wayne.edu [Department of Geology, Wayne State University, Detroit, MI 48202 (United States); Olszewska, Dorota [Department of Geology, Wayne State University, Detroit, MI 48202 (United States)

2011-03-15

An urban soil chronosequence in downtown Detroit, MI was studied to determine the effects of time on pedogenesis and heavy metal sequestration. The soils developed in fill derived from mixed sandy and clayey diamicton parent materials on a level late Pleistocene lakebed plain under grass vegetation in a humid-temperate (mesic) climate. The chronosequence is comprised of soils in vacant lots (12 and 44 years old) and parks (96 and 120 years old), all located within 100 m of a roadway. An A-horizon 16 cm thick with 2% organic matter has developed after only 12 years of pedogenesis. The 12 year-old soil shows accelerated weathering of iron (e.g. nails) and cement artifacts attributed to corrosion by excess soluble salts of uncertain origin. Carbonate and Fe-oxide are immobilizing agents for heavy metals, hence it is recommended that drywall, plaster, cement and iron artifacts be left in soils at brownfield sites for their ameliorating effects. - Research highlights: > An A horizon has developed in these urban soils after only 12 years of pedogenesis. > Iron and cement artifacts have undergone accelerated weathering due to deicing salts. > One soil is contaminated by lead derived from weathered paint. > Artifact weathering can have ameliorating effects on urban soils contaminated by heavy metals. - Weathering of artifacts can have ameliorating effects on heavy metal-polluted soils at brownfield sites.

Pedogenesis, geochemical forms of heavy metals, and artifact weathering in an urban soil chronosequence, Detroit, Michigan

International Nuclear Information System (INIS)

Howard, Jeffrey L.; Olszewska, Dorota

2011-01-01

An urban soil chronosequence in downtown Detroit, MI was studied to determine the effects of time on pedogenesis and heavy metal sequestration. The soils developed in fill derived from mixed sandy and clayey diamicton parent materials on a level late Pleistocene lakebed plain under grass vegetation in a humid-temperate (mesic) climate. The chronosequence is comprised of soils in vacant lots (12 and 44 years old) and parks (96 and 120 years old), all located within 100 m of a roadway. An A-horizon 16 cm thick with 2% organic matter has developed after only 12 years of pedogenesis. The 12 year-old soil shows accelerated weathering of iron (e.g. nails) and cement artifacts attributed to corrosion by excess soluble salts of uncertain origin. Carbonate and Fe-oxide are immobilizing agents for heavy metals, hence it is recommended that drywall, plaster, cement and iron artifacts be left in soils at brownfield sites for their ameliorating effects. - Research highlights: → An A horizon has developed in these urban soils after only 12 years of pedogenesis. → Iron and cement artifacts have undergone accelerated weathering due to deicing salts. → One soil is contaminated by lead derived from weathered paint. → Artifact weathering can have ameliorating effects on urban soils contaminated by heavy metals. - Weathering of artifacts can have ameliorating effects on heavy metal-polluted soils at brownfield sites.

Generation of Caustics and Rogue Waves from Nonlinear Instability.

Science.gov (United States)

Safari, Akbar; Fickler, Robert; Padgett, Miles J; Boyd, Robert W

2017-11-17

Caustics are phenomena in which nature concentrates the energy of waves and may exhibit rogue-type behavior. Although they are known mostly in optics, caustics are intrinsic to all wave phenomena. As we demonstrate in this Letter, the formation of caustics and consequently rogue events in linear systems requires strong phase fluctuations. We show that nonlinear phase shifts can generate sharp caustics from even small fluctuations. Moreover, in that the wave amplitude increases dramatically in caustics, nonlinearity is usually inevitable. We perform an experiment in an optical system with Kerr nonlinearity, simulate the results based on the nonlinear Schrödinger equation, and achieve perfect agreement. As the same theoretical framework is used to describe other wave systems such as large-scale water waves, our results may also aid the understanding of ocean phenomena.

The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTRA Critical Zone Observatory, Guizhou Province, China

Institute of Scientific and Technical Information of China (English)

Oliver W.Moore; Heather L.Buss; Sophie M.Green; Man Liu; Zhaoliang Song

2017-01-01

Soil degradation,including rocky desertification,of the karst regions in China is severe.Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded.Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability,yet little is known about the initial soil forming processes on karst terrain.Herein we examine the initial weathering processes of several types of carbonate bedrock containing varying amounts of non-carbonate minerals in the SPECTRA Critical Zone Observatory,Guizhou Province,Southwest China.We compared the weathering mechanisms of the bedrock to the mass transfer of mineral nutrients in a soil profile developed on these rocks and found that soil formation and nutrient contents are strongly dependent upon the weathering of interbedded layers of more silicate-rich bedrock (marls).Atmospheric inputs from dust were also detected.

Waste site grouping for 200 Areas soil investigations

International Nuclear Information System (INIS)

1997-01-01

The purpose of this document is to identify logical waste site groups for characterization based on criteria established in the 200 Areas Soil Remediation Strategy (DOE-RL 1996a). Specific objectives of the document include the following: finalize waste site groups based on the approach and preliminary groupings identified in the 200 Areas Soil Remediation Strategy; prioritize the waste site groups based on criteria developed in the 200 Areas Soil Remediation Strategy; select representative site(s) that best represents typical and worse-case conditions for each waste group; develop conceptual models for each waste group. This document will serve as a technical baseline for implementing the 200 Areas Soil Remediation Strategy. The intent of the document is to provide a framework, based on waste site groups, for organizing soil characterization efforts in the 200 Areas and to present initial conceptual models

Assessing and monitoring soil quality at agricultural waste disposal areas-Soil Indicators

Science.gov (United States)

Doula, Maria; Kavvadias, Victor; Sarris, Apostolos; Lolos, Polykarpos; Liakopoulou, Nektaria; Hliaoutakis, Aggelos; Kydonakis, Aris

2014-05-01

The necessity of elaborating indicators is one of the priorities identified by the United Nations Convention to Combat Desertification (UNCCD). The establishment of an indicator monitoring system for environmental purposes is dependent on the geographical scale. Some indicators such as rain seasonality or drainage density are useful over large areas, but others such as soil depth, vegetation cover type, and land ownership are only applicable locally. In order to practically enhance the sustainability of land management, research on using indicators for assessing land degradation risk must initially focus at local level because management decisions by individual land users are taken at this level. Soils that accept wastes disposal, apart from progressive degradation, may cause serious problems to the surrounding environment (humans, animals, plants, water systems, etc.), and thus, soil quality should be necessarily monitored. Therefore, quality indicators, representative of the specific waste type, should be established and monitored periodically. Since waste composition is dependent on their origin, specific indicators for each waste type should be established. Considering agricultural wastes, such a specification, however, could be difficult, since almost all agricultural wastes are characterized by increased concentrations of the same elements, namely, phosphorous, nitrogen, potassium, sulfur, etc.; contain large amounts of organic matter; and have very high values of chemical oxygen demand (COD), biochemical oxygen demand (BOD), and electrical conductivity. Two LIFE projects, namely AgroStrat and PROSODOL are focused on the identification of soil indicators for the assessment of soil quality at areas where pistachio wastes and olive mill wastes are disposed, respectively. Many soil samples were collected periodically for 2 years during PROSODOL and one year during AgroStrat (this project is in progress) from waste disposal areas and analyzed for 23 parameters

Method for assay of radioactivity in waste soil

International Nuclear Information System (INIS)

Bramlitt, E.T.; Willhoite, S.B.

1991-01-01

Contaminated soil is a result of many nuclear operations. During facility decommissioning or site cleanup, it may be packaged for disposal. The waste soil must be assayed for contaminants to follow transport regulations and waste handling facility requirements. Methods used for assay include the following: (1) sampling the ground before excavation and assuming ground data apply to soil when packaged; (2) analyzing samples taken from the soil added to a package; (3) counting radiation at the exterior of the package; and (4) measuring neutron absorption by packaged waste soil. The Defense Nuclear Agency (DNA) worked with Eberline Instruments Corporation (EIC) to develop an automated assay method for the waste stream in a plutonium-contaminated soil cleanup at Johnston Atoll in the North Pacific Ocean. The perfected method uses a personal computer, an electronic weighing scale, and a programmable radiation counter. Computer programs get weight and radiation counts at frequent intervals as packages fill, calculate activity in the waste, and produce reports. The automated assay method is an efficient one-person routine that steadfastly collects data and produces a comprehensive record on packaged waste

Cadmium contamination of agricultural soils and crops resulting from sphalerite weathering

International Nuclear Information System (INIS)

Robson, T.C.; Braungardt, C.B.; Rieuwerts, J.; Worsfold, P.

2014-01-01

The biogeochemistry and bioavailability of cadmium, released during sphalerite weathering in soils, were investigated under contrasting agricultural scenarios to assess health risks associated with sphalerite dust transport to productive soils from mining. Laboratory experiments (365 d) on temperate and sub-tropical soils amended with sphalerite ( −1 ). Wheat grown in spiked temperate soil accumulated ≈38% (29 μmol kg −1 ) of the liberated Cd, exceeding food safety limits. In contrast, rice grown in flooded sub-tropical soil accumulated far less Cd (0.60 μmol kg −1 ) due to neutral soil pH and Cd bioavailability was possibly also controlled by secondary sulfide formation. The results demonstrate long-term release of Cd to soil porewaters during sphalerite weathering. Under oxic conditions, Cd may be sufficiently bioavailable to contaminate crops destined for human consumption; however flooded rice production limits the impact of sphalerite contamination. -- Highlights: • Sphalerite containing cadmium presents a hazard when present in agricultural soils. • Sphalerite dissolution was slow (0.6–1.2% y −1 ) but constant in contrasting soils. • Cadmium was released during dissolution and was bioavailable to wheat and rice. • Wheat grains accumulated potentially harmful cadmium concentrations. • Flooded paddy (reducing) soils reduced cadmium bioavailability to rice. -- Sphalerite dissolves steadily in oxic agricultural soils and can release highly bioavailable Cd, which may contaminate food crops destined for human consumption

Weathering behavior of mine tailings and waste rock: A surface investigation

International Nuclear Information System (INIS)

Domvile, S.J.; Li, M.G.; Sollner, D.D.; Nesbitt, W.

1994-01-01

A study focusing on the ion movement in the near surface of sulfide minerals was conducted to better understand the weathering mechanisms of mine waste materials. Tailings and waste rock samples from Canadian mines were subjected to controlled weathering studies using various chemical leachants. Leachates were analyzed for various parameters, and petrographic analyses were conducted on the solid residues. Laboratory oxidation studies of pure pyrrhotite and arsenopyrite were carried out using the surface techniques X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES). The data derived from the weathering study and the surface techniques were correlated to determine mechanisms of oxidation. Several results were observed during the project: ferric iron constitutes one third of the iron present in pyrrhotite, sulfide oxidation is initiated when rock is blasted, sulfide sulfur is oxidized to di- and poly-sulfides prior to forming sulfates, and significantly more sulfate is produced upon exposure to aqueous environments than to air alone

Deep Soil Carbon in the Critical Zone: Amount and Nature of Carbon in Weathered Bedrock, and its Implication for Soil Carbon Inventory

Science.gov (United States)

Moreland, K. C.; Tian, Z.; Berhe, A. A.; O'Geen, A. T.

2017-12-01

Globally, soils store more carbon (C) than the vegetation and the atmosphere combined. Up to 60-80% of the C stored in soils is found in below 30cm soil depth, but there is little data on C storage in weathered bedrock or saprolite. Deep soil organic matter (SOM) can be a mixture of new and old SOM; that is rendered relatively stable due to burial, aggregation, its disconnection from decomposers, and chemical association that organic matter forms with soil minerals. The limited data available on deep SOM dynamics suggests that stock, distribution, and composition of deep SOM are strongly correlated to climate. The overall objective of this research is to investigate how climate regulates OM storage, composition, stability, and stabilization mechanisms. Expecting that the amount of OM stored in deep soil and the stability are a function of soil thickness and availability of weathering products (i.e. reactive minerals), the stock and stability of deep SOM is expected to follow a similar relationship with climate, as does the intensity of weathering. This research is conducted in the NSF funded Southern Sierra Critical Zone Observatories that is located along a climosequence, the western slopes of the Sierra Naevada Mountains of California. Here we will present results derived from characterization of soils and weathered bedrock using elemental and stable isotope elemental analysis, and Fourier Transformed Infrared Spectroscopy to determine OM concentration and functional group level composition of bulk SOM. Our findings show that adding in subsoil and weathered bedrock C stocks increases estimates of soil C stock by 1/3rd to 2/3rd.

Effect of heating rate on caustic stress corrosion cracking

International Nuclear Information System (INIS)

Indig, M.E.; Hoffman, N.J.

1977-01-01

To evaluate effects of a large water leak into the sodium side of a steam generator in a Liquid Metal Fast Breeder Reactor the Liquid Metal Engineering Center (LMEC) at Canoga Park, California, is performing a series of tests in a Large Leak Test Rig (LLTR). This test series involves heating a large steam generator that possibly contains localized pockets of aqueous caustic retained from a previous sodium-water reaction. Such pockets of caustic solution could be in contact with welds and other components that contain residual stresses up to the yield point. The LMEC and General Electric (GE) ran a series of tests to evaluate the effect of heating rate on caustic stress corrosion cracking (SCC) for alloys either used or considered for the LLTR. A summary of the temperatures and caustic concentration ranges that can result in caustic SCC for carbon steel and Type-304 stainless steel is given

Next Generation Solvent Development for Caustic-Side Solvent Extraction of Cesium

Energy Technology Data Exchange (ETDEWEB)

Moyer, Bruce A. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Birdwell, Joseph F. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Bonnesen, Peter V. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

2014-03-01

This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University confirmed a chemical model for cesium distribution ratios (DCs) as a function of feed composition. Inter laboratory efforts were coordinated with complementary engineering tests carried out (and reported separately) by personnel at Savannah River National Laboratory (SRNL) and Savannah River Remediation (SRR) with helpful advice by Parsons Engineering and General Atomics on aspects of possible SWPF implementation.

Extraction, Scrub, and Strip Test Results for the Salt Waste Processing Facility Caustic Side Solvent Extraction Solvent Sample

Energy Technology Data Exchange (ETDEWEB)

Peters, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-10-06

An Extraction, Scrub, and Strip (ESS) test was performed on a sample of Salt Waste Processing Facility (SWPF) Caustic-Side Solvent Extraction (CSSX) solvent and salt simulant to determine cesium distribution ratios (D(_Cs)), and cesium concentration in the strip effluent (SE) and decontaminated salt solution (DSS) streams; this data will be used by Parsons to help determine if the solvent is qualified for use at the SWPF. The ESS test showed acceptable performance of the solvent for extraction, scrub, and strip operations. The extraction D(_Cs) measured 12.5, exceeding the required value of 8. This value is consistent with results from previous ESS tests using similar solvent formulations. Similarly, scrub and strip cesium distribution ratios fell within acceptable ranges. This revision was created to correct an error. The previous revision used an incorrect set of temperature correction coefficients which resulted in slight deviations from the correct D(_Cs) results.

Defense Waste Management Plan for buried transuranic-contaminated waste, transuranic-contaminated soil, and difficult-to-certify transuranic waste

International Nuclear Information System (INIS)

1987-06-01

GAO recommended that DOE provide specific plans for permanent disposal of buried TRU-contaminated waste, TRU-contaminated soil, and difficult-to-certify TRU waste; cost estimates for permanent disposal of all TRU waste, including the options for the buried TRU-contaminated waste, TRU-contaminated soil, and difficult-to-certify TRU waste; and specific discussions of environmental and safety issues for the permanent disposal of TRU waste. Purpose of this document is to respond to the GAO recommendations by providing plans and cost estimates for the long-term isolation of the buried TRU-contaminated waste, TRU-contaminated soil, and difficult-to-certify TRU waste. This report also provides cost estimates for processing and certifying stored and newly generated TRU waste, decontaminating and decommissioning TRU waste processing facilities, and interim operations

On the assimilation of satellite derived soil moisture in numerical weather prediction models

Science.gov (United States)

Drusch, M.

2006-12-01

Satellite derived surface soil moisture data sets are readily available and have been used successfully in hydrological applications. In many operational numerical weather prediction systems the initial soil moisture conditions are analysed from the modelled background and 2 m temperature and relative humidity. This approach has proven its efficiency to improve surface latent and sensible heat fluxes and consequently the forecast on large geographical domains. However, since soil moisture is not always related to screen level variables, model errors and uncertainties in the forcing data can accumulate in root zone soil moisture. Remotely sensed surface soil moisture is directly linked to the model's uppermost soil layer and therefore is a stronger constraint for the soil moisture analysis. Three data assimilation experiments with the Integrated Forecast System (IFS) of the European Centre for Medium-range Weather Forecasts (ECMWF) have been performed for the two months period of June and July 2002: A control run based on the operational soil moisture analysis, an open loop run with freely evolving soil moisture, and an experimental run incorporating bias corrected TMI (TRMM Microwave Imager) derived soil moisture over the southern United States through a nudging scheme using 6-hourly departures. Apart from the soil moisture analysis, the system setup reflects the operational forecast configuration including the atmospheric 4D-Var analysis. Soil moisture analysed in the nudging experiment is the most accurate estimate when compared against in-situ observations from the Oklahoma Mesonet. The corresponding forecast for 2 m temperature and relative humidity is almost as accurate as in the control experiment. Furthermore, it is shown that the soil moisture analysis influences local weather parameters including the planetary boundary layer height and cloud coverage. The transferability of the results to other satellite derived soil moisture data sets will be discussed.

PEP Integrated Test D Run Report Caustic and Oxidative Leaching in UFP-VSL-T02A

Energy Technology Data Exchange (ETDEWEB)

Sevigny, Gary J.; Bredt, Ofelia P.; Burns, Carolyn A.; Kurath, Dean E.; Geeting, John GH; Golovich, Elizabeth C.; Guzman-Leong, Consuelo E.; Josephson, Gary B.

2009-12-11

Pacific Northwest National Laboratory (PNNL) has been tasked by Bechtel National Inc. (BNI) on the River Protection Project-Hanford Tank Waste Treatment and Immobilization Plant (RPP-WTP) project to perform research and development activities to resolve technical issues identified for the Pretreatment Facility (PTF). The Pretreatment Engineering Platform (PEP) was designed, constructed and operated as part of a plan to respond to issue M12, "Undemonstrated Leaching Processes" of the External Flowsheet Review Team (EFRT) issue response plan. The PEP is a 1/4.5-scale test platform designed to simulate the WTP pretreatment caustic leaching, oxidative leaching, ultrafiltration solids concentration, and slurry washing processes. The PEP replicates the WTP leaching processes using prototypic equipment and control strategies. The PEP also includes non-prototypic ancillary equipment to support the core processing. Two operating scenarios are currently being evaluated for the ultrafiltration process (UFP) and leaching operations. The first scenario (Test B and D) has caustic leaching performed in the UFP-2 ultrafiltration feed vessels (i.e., vessel UFP-VSL-T02A in the PEP and vessels UFP-VSL-00002A and B in the WTP PTF). The second scenario (Test A) has caustic leaching conducted in the UFP-1 ultrafiltration feed preparation vessels (i.e., vessels UFP-VSL-T01A and B in the PEP and vessels UFP VSL-00001A and B in the WTP PTF). In Test D, 19M sodium hydroxide (NaOH, caustic) was added to the waste slurry in the UFP VSL T02 vessel after the solids were concentrated to ~20% undissolved solids. The NaOH was added to leach solid aluminum compounds (e.g., gibbsite, boehmite). Caustic addition is followed by heating to 85°C using direct injection of steam to accelerate the leach process. The main difference of Test D compared to Test B is that the leach temperature is 85°C for 24 hrs as compared to 100°C for 12 hours. The other difference is the Test D simulant had Cr in the

Spectral Caustics in Attosecond Science

Directory of Open Access Journals (Sweden)

Dudovich N.

2013-03-01

Full Text Available A unique type of singularity common in wave phenomena, known as caustics, links processes observed in many different branches of physics [1]. We investigate the role of caustics in attosecond science and in particular the physical process behind high harmonic generation. By exploiting singularities of the three-step model that describes HHG, we can manipulate and enhance specific features in the emitted harmonic spectrum. This new level of control holds promises in both scientific and technological aspects of attosecond science, and provides a deeper insight into the basic mechanism underlying the high harmonic generation process.

Effect of long-term electrodialytic soil remediation on Pb removal and soil weathering

DEFF Research Database (Denmark)

Skibsted, Gry; Ottosen, Lisbeth M.; Elektorowicz, Maria

2017-01-01

Weathering of soil minerals during long-term electrochemical soil remediation was evaluated for two different soils: an industrially Pb contaminated soil with high carbonate content and an unpolluted soil with low carbonate content. A constant current of 5 mA was applied for 842 days, and sampling...... was made 22 times during the treatment. The overall qualitative mineral composition was unaffected by electrodialysis, except for calcite removal which was complete. However, dissolution and removal of Al, Fe, Si, Mg, Ca and Pb from the soil during the treatment exceeded the fraction extractable by...... digestion in 7 M HNO3, and provided evidence of enhanced mineral dissolution induced by the current. Nevertheless, the total dissolved Si and Al only constituted 0.2-0.3 % and 1.1-3.5 % of the total content, while the Pb overall removal from the contaminated soil was only 8.1 %. An observed reduction in the...

Aeolian controls of soil geochemistry and weathering fluxes in high-elevation ecosystems of the Rocky Mountains, Colorado

Science.gov (United States)

Lawrence, Corey R.; Reynolds, Richard L.; Kettterer, Michael E.; Neff, Jason C.

2013-01-01

When dust inputs are large or have persisted for long periods of time, the signature of dust additions are often apparent in soils. The of dust will be greatest where the geochemical composition of dust is distinct from local sources of soil parent material. In this study the influence of dust accretion on soil geochemistry is quantified for two different soils from the San Juan Mountains of southwestern Colorado, USA. At both study sites, dust is enriched in several trace elements relative to local rock, especially Cd, Cu, Pb, and Zn. Mass-balance calculations that do not explicitly account for dust inputs indicate the accumulation of some elements in soil beyond what can be explained by weathering of local rock. Most observed elemental enrichments are explained by accounting for the long-term accretion of dust, based on modern isotopic and geochemical estimates. One notable exception is Pb, which based on mass-balance calculations and isotopic measurements may have an additional source at one of the study sites. These results suggest that dust is a major factor influencing the development of soil in these settings and is also an important control of soil weathering fluxes. After accounting for dust inputs in mass-balance calculations, Si weathering fluxes from San Juan Mountain soils are within the range observed for other temperate systems. Comparing dust inputs with mass-balanced based flux estimates suggests dust could account for as much as 50–80% of total long-term chemical weathering fluxes. These results support the notion that dust inputs may sustain chemical weathering fluxes even in relatively young continental settings. Given the widespread input of far-traveled dust, the weathering of dust is likely and important and underappreciated aspect of the global weathering engine.

Aeolian controls of soil geochemistry and weathering fluxes in high-elevation ecosystems of the Rocky Mountains, Colorado

Science.gov (United States)

Lawrence, Corey R.; Reynolds, Richard L.; Ketterer, Michael E.; Neff, Jason C.

2013-04-01

When dust inputs are large or have persisted for long periods of time, the signature of dust additions are often apparent in soils. The of dust will be greatest where the geochemical composition of dust is distinct from local sources of soil parent material. In this study the influence of dust accretion on soil geochemistry is quantified for two different soils from the San Juan Mountains of southwestern Colorado, USA. At both study sites, dust is enriched in several trace elements relative to local rock, especially Cd, Cu, Pb, and Zn. Mass-balance calculations that do not explicitly account for dust inputs indicate the accumulation of some elements in soil beyond what can be explained by weathering of local rock. Most observed elemental enrichments are explained by accounting for the long-term accretion of dust, based on modern isotopic and geochemical estimates. One notable exception is Pb, which based on mass-balance calculations and isotopic measurements may have an additional source at one of the study sites. These results suggest that dust is a major factor influencing the development of soil in these settings and is also an important control of soil weathering fluxes. After accounting for dust inputs in mass-balance calculations, Si weathering fluxes from San Juan Mountain soils are within the range observed for other temperate systems. Comparing dust inputs with mass-balanced based flux estimates suggests dust could account for as much as 50-80% of total long-term chemical weathering fluxes. These results support the notion that dust inputs may sustain chemical weathering fluxes even in relatively young continental settings. Given the widespread input of far-traveled dust, the weathering of dust is likely and important and underappreciated aspect of the global weathering engine.

Water washes and caustic leaches of sludge from Hanford Tank S-101 and water washes of sludge from Hanford Tank C-103

International Nuclear Information System (INIS)

Hunt, R.D.; Collins, J.L.; Chase, C.W.

1998-07-01

In 1993, the Department of Energy (DOE) selected the enhanced sludge washing (ESW) process as the baseline for pretreatment of Hanford tank sludges. The ESW process uses a series of water washes and caustic leaches to separate nonradioactive components such as aluminum, chromium, and phosphate from the high-level waste sludges. If the ESW process is successful, the volume of immobilized high-level waste will be significantly reduced. The tests on the sludge from Hanford Tank S-101 focused on the effects of process variables such as sodium hydroxide concentration (1 and 3 M), temperature (70 and 95 C), and leaching time (5, 24, 72, and 168 h) on the efficacy of the ESW process with realistic liquid-to-solid ratios. Another goal of this study was to evaluate the effectiveness of water washes on a sludge sample from hanford Tank C-103. The final objective of this study was to test potential process control monitors during the water washes and caustic leaches with actual sludge. Both 137 Cs activity and conductance were measured for each of the water washes and caustic leaches. Experimental procedures, a discussion of results, conclusions and recommendations are included in this report

Results Of The Extraction-Scrub-Strip Testing Using An Improved Solvent Formulation And Salt Waste Processing Facility Simulated Waste

International Nuclear Information System (INIS)

Peters, T.; Washington, A.; Fink, S.

2012-01-01

The Office of Waste Processing, within the Office of Technology Innovation and Development, is funding the development of an enhanced solvent - also known as the next generation solvent (NGS) - for deployment at the Savannah River Site to remove cesium from High Level Waste. The technical effort is a collaborative effort between Oak Ridge National Laboratory (ORNL) and Savannah River National Laboratory (SRNL). As part of the program, the Savannah River National Laboratory (SRNL) has performed a number of Extraction-Scrub-Strip (ESS) tests. These batch contact tests serve as first indicators of the cesium mass transfer solvent performance with actual or simulated waste. The test detailed in this report used simulated Tank 49H material, with the addition of extra potassium. The potassium was added at 1677 mg/L, the maximum projected (i.e., a worst case feed scenario) value for the Salt Waste Processing Facility (SWPF). The results of the test gave favorable results given that the potassium concentration was elevated (1677 mg/L compared to the current 513 mg/L). The cesium distribution value, DCs, for extraction was 57.1. As a comparison, a typical D Cs in an ESS test, using the baseline solvent formulation and the typical waste feed, is ∼15. The Modular Caustic Side Solvent Extraction Unit (MCU) uses the Caustic-Side Solvent Extraction (CSSX) process to remove cesium (Cs) from alkaline waste. This process involves the use of an organic extractant, BoBCalixC6, in an organic matrix to selectively remove cesium from the caustic waste. The organic solvent mixture flows counter-current to the caustic aqueous waste stream within centrifugal contactors. After extracting the cesium, the loaded solvent is stripped of cesium by contact with dilute nitric acid and the cesium concentrate is transferred to the Defense Waste Processing Facility (DWPF), while the organic solvent is cleaned and recycled for further use. The Salt Waste Processing Facility (SWPF), under

Test report - caustic addition system operability test procedure

International Nuclear Information System (INIS)

Parazin, R.E.

1995-01-01

This Operability Test Report documents the test results of test procedure WHC-SD-WM-OTP-167 ''Caustic Addition System Operability Test Procedure''. The Objective of the test was to verify the operability of the 241-AN-107 Caustic Addition System. The objective of the test was met

Soils and climate: redness and weathering as indicators of mean annual precipitation

Science.gov (United States)

Lucke, Bernhard

2016-04-01

Paleosols can be used as archives of past changes of climate and landscapes, but their interpretation has to be based on modern analogies such as Budyko's law of soil zonality. These can be very useful if the respective processes of soil formation are sufficiently well understood. However, some soils such as the Terra Rossa or Red Mediterranean Soils, that are widespread at the fringes of the steppes and deserts, are still disputed with regard to their genesis and environmental significance. In particular, there is no agreement whether they resemble current environmental conditions, or are inherited from climates or sediments of the past. In this context, a remarkable change of the color of surface soils can be observed when driving from the city of Irbid in Jordan towards the east. Soil color apparently changes slowly, but steadily from dark red to yellow colors. However, attempting to express these color changes in numerical form is challenging, and it seemed questionable whether color is indeed connected with soil weathering intensity, or an optical illusion. However, a systematic comparison of different approaches of calculating soil redness found that the CIELAB-color system is suited for numerical expressions of soil redness and performs better than the Munsell charts. Along the investigated transect in Jordan, soil color seems strongly connected with weathering intensity, since various weathering indicators point to a steady increase of soil development with moisture. This suggests that such indices can well be used in semi-arid areas of 250-600 mm of mean annual precipitation. A very strong correlation of magnetic enhancement and rainfall indicates that the investigated soils are forming in equilibrium with current climatic conditions, and regressions based on this gradient might be suited for estimating paleorainfalls recorded by buried paelosols. It seems therefore that surface Terra Rossa soils in Jordan can be in equilibrium with current climate

Next Generation Solvent (NGS): Development for Caustic-Side Solvent Extraction of Cesium

Energy Technology Data Exchange (ETDEWEB)

Moyer, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Birdwell, Jr, Joseph F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bonnesen, Peter V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Delmau, Laetitia Helene [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Duncan, Nathan C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ensor, Dale [Tennessee Technological Univ., Cookeville, TN (United States); Hill, Talon G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Denise L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rajbanshi, Arbin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Roach, Benjamin D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Szczygiel, Patricia L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sloop, Jr., Frederick V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stoner, Erica L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Williams, Neil J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-03-01

This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University confirmed a chemical model for cesium distribution ratios (DCs) as a function of feed composition. Interlaboratory efforts were coordinated with complementary engineering tests carried out (and reported separately) by personnel at Savannah River National Laboratory (SRNL) and Savannah River Remediation (SRR) with helpful advice by Parsons Engineering and General Atomics on aspects of possible SWPF implementation.

Filamentous fungi remove weathered hydrocarbons from polluted soil of tropical Mexico

OpenAIRE

PÉREZ-ARMENDÁRIZ, Beatriz; MARTÍNEZ-CARRERA, Daniel; CALIXTO-MOSQUEDA, María; ALBA, Joel; RODRÍGUEZ-VÁZQUEZ, Refugio

2010-01-01

Weathered hydrocarbons from worldwide petrolic activities become more recalcitrant over time. The removal of petroleum hydrocarbons from a polluted soil [65,000 mg total petroleum hydrocarbons (TPH)/kg soil], which had been exposed to tropical environmental conditions for more than 20 years in southeast Mexico, was studied using filamentous fungi. Experiments were carried out in batch reactors (60 mL) containing a substrate consisting of polluted soil and sugar cane bagasse pith as bulk agent...

Assesment of a soil moisture retrieval with numerical weather prediction model temperature

Science.gov (United States)

The effect of using a Numerical Weather Prediction (NWP) soil temperature product instead of estimates provided by concurrent 37 GHz data on satellite-based passive microwave retrieval of soil moisture retrieval was evaluated. This was prompted by the change in system configuration of preceding mult...

Catastrophe Theory and Caustics

DEFF Research Database (Denmark)

Gravesen, Jens

1983-01-01

It is shown by elementary methods that in codimension two and under the assumption that light rays are straight lines, a caustic is the catastrophe set for a time function. The general case is also discussed....

Determination of soil weathering rates with U-Th series disequilibria: approach on bulk soil and selected mineral phases

International Nuclear Information System (INIS)

Gontier, Adrien

2014-01-01

The aim of the present study was to evaluate weathering and soil formation rates using U-Th disequilibria in bulk soil or separated minerals. The specific objectives of this work were to evaluate the use of U-Th chronometric tools 1) regarding the impact of a land cover change and the bedrock characteristics 2) in selected secondary mineral phases and 3) in primary minerals. On the Breuil-Chenue (Morvan) site, no vegetation effect neither a grain size effect was observed on the U-Th series in the deepest soil layers (≤ 40 cm). The low soil production rate (1-2 mm/ka) is therefore more affected by regional geomorphology than by the underlying bedrock texture. In the second part of this work, based on a thorough evaluation of different techniques, a procedure was retained to extract Fe-oxides without chemical fractionation. Finally, the analysis of biotites hand-picked from one of the studied soil profile showed that U-series disequilibria allow to independently determinate the field-weathering-rate of minerals. (author)

Strontium and cesium release mechanisms during unsaturated flow through waste-weathered Hanford sediments

International Nuclear Information System (INIS)

Chang, Hyun-Shik; Um, Wooyong; Rod, Kenton A.; Serne, R. Jeffrey; Thompson, Aaron; Perdrial, Nicolas; Steefel, Carl I.; Chorover, Jon

2011-01-01

Leaching behavior of Sr and Cs in the vadose zone of Hanford site (WA, USA) was studied with laboratory-weathered sediments mimicking realistic conditions beneath the leaking radioactive waste storage tanks. Unsaturated column leaching experiments were conducted using background Hanford pore water focused on first 200 pore volumes. The weathered sediments were prepared by 6 months reaction with a synthetic Hanford tank waste leachate containing Sr and Cs (10-5 and 10-3 molal representative of LO- and HI-sediment, respectively) as surrogates for 90Sr and 137Cs. The mineral composition of the weathered sediments showed that zeolite (chabazite-type) and feldspathoid (sodalite-type) were the major byproducts but different contents depending on the weathering conditions. Reactive transport modeling indicated that Cs leaching was controlled by ion-exchange, while Sr release was affected primarily by dissolution of the secondary minerals. The later release of K, Al, and Si from the HI-column indicated the additional dissolution of a more crystalline mineral (cancrinite-type). A two-site ion-exchange model successfully simulated the Cs release from the LO-column. However, a three-site ion-exchange model was needed for the HI-column. The study implied that the weathering conditions greatly impact the speciation of the secondary minerals and leaching behavior of sequestrated Sr and Cs.

The role of soil weathering and hydrology in regulating chemical fluxes from catchments (Invited)

Science.gov (United States)

Maher, K.; Chamberlain, C. P.

2010-12-01

Catchment-scale chemical fluxes have been linked to a number of different parameters that describe the conditions at the Earth’s surface, including runoff, temperature, rock type, vegetation, and the rate of tectonic uplift. However, many of the relationships relating chemical denudation to surface processes and conditions, while based on established theoretical principles, are largely empirical and derived solely from modern observations. Thus, an enhanced mechanistic basis for linking global solute fluxes to both surface processes and climate may improve our confidence in extrapolating modern solute fluxes to past and future conditions. One approach is to link observations from detailed soil-based studies with catchment-scale properties. For example, a number of recent studies of chemical weathering at the soil-profile scale have reinforced the importance of hydrologic processes in controlling chemical weathering rates. An analysis of data from granitic soils shows that weathering rates decrease with increasing fluid residence times and decreasing flow rates—over moderate fluid residence times, from 5 days to 10 years, transport-controlled weathering explains the orders of magnitude variation in weathering rates to a better extent than soil age. However, the importance of transport-controlled weathering is difficult to discern at the catchment scale because of the range of flow rates and fluid residence times captured by a single discharge or solute flux measurement. To assess the importance of transport-controlled weathering on catchment scale chemical fluxes, we present a model that links the chemical flux to the extent of reaction between the soil waters and the solids, or the fluid residence time. Different approaches for describing the distribution of fluid residence times within a catchment are then compared with the observed Si fluxes for a limited number of catchments. This model predicts high solute fluxes in regions with high run-off, relief, and

Use of Imaging Spectroscopy for Mapping and Quantifying the Weathering Degree of Tropical Soils in Central Brazil

International Nuclear Information System (INIS)

Baptista, G.M.M.; Meneses, P.R.; Correa, R.S.; Dos Santos, P.F.; Correa, R.S.; Jose, S.; Dos Santos, P.F.; Netto, M.

2011-01-01

The purpose of this study was to test the feasibility of applying AVIRIS sensor (Airborne Visible/Infra Red Imaging Spectrometer) for mapping and quantifying mineralogical components of three Brazilian soils, a reddish Oxisol in Sao Joao D'Alianca area (SJA) and a dark reddish brown Oxisol and Ultisol in Niquelandia (NIQ) counties, Goias State. The study applied the spectral index RCGb [kaolinite/(kaolinite + gibbsite) ratio] and was based on spectral absorption features of these two minerals.The RCGb index was developed for the evaluation of weathering degrees of various Brazilian soils and was validated by the analysis of soil samples spectra imaged by AVIRIS and checked against laboratory mineralogical quantification (TGA:Thermal Gravimetric Analysis). Results showed to be possible mapping and quantifying the weathering degree of the studied soils and that the two selected areas presented different weathering degrees of their soils even for a same soil type.

Repeated application of organic waste affects soil organic matter composition

DEFF Research Database (Denmark)

Peltre, Clément; Gregorich, Edward G.; Bruun, Sander

2017-01-01

Land application of organic waste is an important alternative to landfilling and incineration because it helps restore soil fertility and has environmental and agronomic benefits. These benefits may be related to the biochemical composition of the waste, which can result in the accumulation...... of different types of carbon compounds in soil. The objective of this study was to identify and characterise changes in soil organic matter (SOM) composition after repeated applications of organic waste. Soil from the CRUCIAL field experiment in Denmark was sampled after 12 years of annual application...... that there was accumulation in soil of different C compounds for the different types of applied organic waste, which appeared to be related to the degree to which microbial activity was stimulated and the type of microbial communities applied with the wastes or associated with the decomposition of applied wastes...

Cu retention in an acid soil amended with perlite winery waste.

Science.gov (United States)

Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Calviño, David

2016-02-01

The effect of perlite waste from a winery on general soil characteristics and Cu adsorption was assessed. The studied soil was amended with different perlite waste concentrations corresponding to 10, 20, 40 and 80 Mg ha(-1). General soil characteristics and Cu adsorption and desorption curves were determined after different incubation times (from 1 day to 8 months). The addition of perlite waste to the soil increased the amounts of organic matter as well as soil nutrients such as phosphorus and potassium, and these increments were stable with time. An increase in Cu adsorption capacity was also detected in the perlite waste-amended soils. The effect of perlite waste addition to the soil had special relevance on its Cu adsorption capacity at low coverage concentrations and on the energy of the soil-Cu bonds.

Artificial soils and waste products. Theme report 2

Energy Technology Data Exchange (ETDEWEB)

O`Riordan, N.J. [Ove Arup and Partners, London (United Kingdom); Tammirinne, M. [Technical Research Centre of Finland (Finland); Skarzynska, K. [University of Agriculture, Krakow, (Poland)

1995-05-01

Increasing pressure to minimise waste, recycle and manage finite aggregate resources has lead to the use of waste materials for engineered fills. Techniques to deal with materials such as colliery waste and power station ashes are maturing. Other materials such as lime stabilised soils, tyre/soil and polystyrene soil mixtures are being investigated. As efforts to reduce waste continue, so greater demands will be placed upon engineered land filling. This report summarises current practice and applications in this important area of geotechnical activity. Increasing economic and political pressure to reduce waste will lead to the development of many hybrid soils and the reuse of waste materials in innovative ways: thereby extending the chain of utility. Major advances in the understanding of real soils and pore fluids will enable additives such as cements, shredded tyres, expanded polystyrene, etc, to be incorporated with confidence to produce useful and durable engineering materials with predictable behaviour. Large stockpiles of mineral wastes provide a potential source of secondary aggregates. A flexible approach to the specification of engineering materials is needed so that such waste can be reused. Evidence from the reuse of colliery and other waste materials suggests that tunneling spoil can be treated to produce potentially useful secondary aggregates. Material delivered to materials suggests that tunneling spoil can be trated to produce potentially useful secondary aggregates. Material delivered to landfill sites will become progressively higher in contamination content which will place greater demands upon containment systems. Formalised risk assessment of landfill containment systems will grow, and further research in definition of failure scenarios and probability of occurrence is necessary. (AB) 71 refs.

Stress-strain response of plastic waste mixed soil.

Science.gov (United States)

Babu, G L Sivakumar; Chouksey, Sandeep Kumar

2011-03-01

Recycling plastic waste from water bottles has become one of the major challenges worldwide. The present study provides an approach for the use plastic waste as reinforcement material in soil. The experimental results in the form of stress-strain-pore water pressure response are presented. Based on experimental test results, it is observed that the strength of soil is improved and compressibility reduced significantly with addition of a small percentage of plastic waste to the soil. The use of the improvement in strength and compressibility response due to inclusion of plastic waste can be advantageously used in bearing capacity improvement and settlement reduction in the design of shallow foundations. Copyright © 2010 Elsevier Ltd. All rights reserved.

Tectonic uplift and denudation rate influence soil chemical weathering intensity in a semi-arid environment, southeast Spain: physico-chemical and mineralogical evidence

Science.gov (United States)

Ameijeiras-Mariño, Yolanda; Opfergelt, Sophie; Schoonejans, Jérôme; Vanacker, Veerle; Sonnet, Philippe; Delmelle, Pierre

2015-04-01

Tectonic uplift is known to influence denudation rates. Denudation, including chemical weathering and physical erosion, affects soil production rates and weathering intensities. At topographic steady state, weathering can be transport- or weathering-limited. In the transport-limited regime, low denudation rates should lead to comparatively high weathering intensities, while in the weathering-limited case high denudation rates are associated with lower weathering intensities. Here, we test if this relationship applies to semi-arid environments where chemical weathering is generally slow. Three catchments (EST, FIL and CAB) were studied in the Internal Zone of the Betic Cordillera in southeast Spain, spanning a range of increasing uplift rates (10-170 mm/kyr) and increasing denudation rates (20-250 mm/kyr) from EST to CAB. In each catchment, two ridgetop soil profiles were sampled down to the bedrock. The three catchments have similar vegetation and climatic conditions, with precipitation of 250- 315 mm/yr and mean annual temperature of 15-17 °C. The mineralogy of the bedrock, as determined by XRD, is similar across the three catchments and is characterized by the presence of quartz, muscovite, clinochlore, biotite and plagioclase. This primary mineral assemblage is also found in the catchment soils, indicating that the soils studied derive from the same parent material. The soil clay-size fraction is dominated by kaolinite, vermiculite and illite. However, the proportions of the soil primary and secondary minerals vary between the catchment sites. The abundance of biotite decreases from CAB (14%) to EST (4%), whereas the quartz and clay contents show an opposite tendency (from 30 to 69% and 9.9 to 14.3%, respectively). Further, the abundance of vermiculite increases from CAB to EST. The results are interpreted in terms of increasing weathering intensity from CAB to EST by weathering of biotite into vermiculite and enrichment of soils on more weathering resistant

A practical approach for deriving all-weather soil moisture content using combined satellite and meteorological data

Science.gov (United States)

Leng, Pei; Li, Zhao-Liang; Duan, Si-Bo; Gao, Mao-Fang; Huo, Hong-Yuan

2017-09-01

Soil moisture has long been recognized as one of the essential variables in the water cycle and energy budget between Earth's surface and atmosphere. The present study develops a practical approach for deriving all-weather soil moisture using combined satellite images and gridded meteorological products. In this approach, soil moisture over the Moderate Resolution Imaging Spectroradiometer (MODIS) clear-sky pixels are estimated from the Vegetation Index/Temperature (VIT) trapezoid scheme in which theoretical dry and wet edges were determined pixel to pixel by China Meteorological Administration Land Data Assimilation System (CLDAS) meteorological products, including air temperature, solar radiation, wind speed and specific humidity. For cloudy pixels, soil moisture values are derived by the calculation of surface and aerodynamic resistances from wind speed. The approach is capable of filling the soil moisture gaps over remaining cloudy pixels by traditional optical/thermal infrared methods, allowing for a spatially complete soil moisture map over large areas. Evaluation over agricultural fields indicates that the proposed approach can produce an overall generally reasonable distribution of all-weather soil moisture. An acceptable accuracy between the estimated all-weather soil moisture and in-situ measurements at different depths could be found with an Root Mean Square Error (RMSE) varying from 0.067 m3/m3 to 0.079 m3/m3 and a slight bias ranging from 0.004 m3/m3 to -0.011 m3/m3. The proposed approach reveals significant potential to derive all-weather soil moisture using currently available satellite images and meteorological products at a regional or global scale in future developments.

Dermal absorption of benzo[a]pyrene into human skin from soil: Effect of artificial weathering, concentration, and exposure duration.

Science.gov (United States)

Peckham, Trevor K; Shirai, Jeffry H; Bunge, Annette L; Lowney, Yvette W; Ruby, Michael V; Kissel, John C

2017-11-01

In vitro assessments of 14 C-benzo[a]pyrene (BaP) absorption through human epidermis were conducted with the sub-63-μm fraction of four test soils containing different amounts of organic and black carbon. Soils were artificially weathered for eight weeks and applied to epidermis at nominal BaP concentrations of 3 and 10 mg/kg for 8 or 24 h. Experiments were also conducted at 24 h with unweathered soils and with BaP deposited onto skin from acetone at a comparable chemical load. For the weathered soils, absorption was independent of the amount of organic or black carbon, the mass in the receptor fluid was proportional to exposure duration but independent of concentration, and the mass recovered in the skin after washing was proportional to concentration and independent of exposure time. Results from the weathered and unweathered soils were similar except for the mass recovered in the washed skin, which was lower for the weathered soil only at the higher concentration. We hypothesize that chemical concentrations exceeded the BaP sorption capacity accessible within the artificial weathering timeframe for all soils tested, and that BaP mass in the washed skin was dominated by particles that were not removed by washing. Fluxes into and through skin from soils were lower by an order of magnitude than from acetone-deposited BaP.

The application of U-isotopes to assess weathering in contrasted soil-water regime in Brazil.

Science.gov (United States)

Rosolen, Vania; Bueno, Guilherme Taitson; Bonotto, Daniel Marcos

2018-02-01

This paper presents the use of U-series radionuclides 238 U and 234 U to evaluate the biogeochemical disequilibrium in soil cover under a contrasted soil-water regime. The approach was applied in three profiles located in distinct topographical positions, from upslope ferralitic to downslope hydromorphic domain. The U fractionation data was obtained in the samples representing the saprolite and the superficial and subsuperficial soil horizons. The results showed a significant and positive correlation between U and the Total Organic Carbon (TOC). Soil organic matter has accumulated in soil due to hydromorphy. There is no evidence of positive correlation between U and Fe, as expected in lateritic soils. The advance of the hydromorphy on Ferralsol changes the weathering rates, and the ages of weathering are discussed as a function of the advance of waterlogged soil conditions from downslope. Also, the bioturbation could represent the other factor responsible to construct a more recent soil horizon. Copyright © 2017 Elsevier Ltd. All rights reserved.

21 CFR 2.110 - Definition of ammonia under Federal Caustic Poison Act.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Definition of ammonia under Federal Caustic Poison... SERVICES GENERAL GENERAL ADMINISTRATIVE RULINGS AND DECISIONS Caustic Poisons § 2.110 Definition of ammonia under Federal Caustic Poison Act. For the purpose of determining whether an article containing ammonia...

Stabilization of soil using plastic waste

International Nuclear Information System (INIS)

Khan, S.A.

2005-01-01

The economy in a soil stabilization project depends on the cost of the stabilizing material. Cheaper the stabilizing material, lesser will be the project cost. Specially manufactured geotextiles are successfully being used for soil stabilization, but the cost is higher. In this study, the cuttings of the waste polyethylene shopper bags have been used to stabilize the soil. The polyethylene shopper bags are transformed to cuttings for easy mixing with the soil by conventional methods. The plastic cuttings acted similar to the non-woven geotextile fibers. Different quantities of the shopper bag cuttings were mixed with the soil. The soil was compacted in the California Bearing Ratio (CBR) test molds according to the British Standards. CBR values of the soil with varying quantities of the plastic cuttings were determined both for the un-soaked and soaked conditions. The tests showed significant increase in the CBR values of the stabilized soil under un-soaked conditions. However, the improvement in the CBR values under the soaked condition was comparatively lesser than that of the un-soaked condition. This method of stabilization proved economical due to low cost of the waste shopper bags. (author)

Soil weathering agents are limited where deep tree roots are removed, even after decades of forest regeneration

Science.gov (United States)

Billings, S. A.; Richter, D. D., Jr.; Hirmas, D.; Lehmeier, C.; Bagchi, S.; Brecheisen, Z.; Sullivan, P. L.; Min, K.; Hauser, E.; Stair, R.; Flournoy, R.

2017-12-01

Deep roots pump reduced C deep into Earth's critical zone (CZ) as they grow and function. This action generates acid-forming CO2 and organic acids (OA) and fosters microbes that also produce these weathering agents. This phenomenon results in a regolith-weathering reaction front that propagates down with vertical root extension and water infiltration. Across old-growth hardwood, younger pine, and annual crop plots at the Calhoun Critical Zone Observatory, we tested the hypothesis that persistent absence of deep roots, a widespread anthropogenic phenomenon, reduces root- and microbially-mediated biogeochemical pools and fluxes important for weathering, even well below maximum root density. We also hypothesized that land use effects on deep soil biogeochemistry is evident even after decades of forest regeneration. Root abundance to 2 m declined with depth, and was greater in old-growth and regenerating forests than in crop plots at most depths. Old-growth soils also contain more roots than younger pine soils: between 30-45 and 70-80 cm depth, old-growth root abundances were greater than in regenerating forests, and old-growth soils exhibited root distributions with less severe declines with depth and harbored more root-associated bacteria than younger forests. Changing root abundances influenced concentrations of weathering agents. At 3 m, in situ soil [CO2] reached 6%, 4%, and 2% in old-growth, regenerating, and crop soils, respectively. Soil organic C (SOC) and extractable OC (EOC, an OA proxy) did not differ across land use, but at 4-5 m EOC/SOC was higher in old-growth compared to regenerating forests and crop soils (20.0±2.6 vs. 2.0±1.0%). We suggest that biogeochemistry deep beneath old-growth forests reflects greater root prevalence and propensity for generation of weathering agents, and that disturbance regimes inducing deep root mortality impose top-down signals relevant to weathering processes deep in Earth's CZ even after decades of forest regeneration.

Thorium, uranium and rare earth elements concentration in weathered Japanese soil samples

International Nuclear Information System (INIS)

Sahoo, Sarata Kumar; Hosoda, Masahiro; Kamagata, Sadatoshi; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Uchida, Shigeo

2011-01-01

The geochemical behavior of thorium, uranium and rare earth elements (REEs) are relatively close to one another while compared to other elements in a geological environment. Radioactive elements like 232 Th and 238 U along with their decay products (e.g. 226 Ra) are present in most environmental matrices and can be transferred to living bodies by different pathways which can lead to the sources of exposure to man. For these reasons, it has been necessary to monitor those natural radionuclides in weathered soil samples to assess the possible hazards. It has been observed that granitic rocks contain higher amounts of U, Th and light REEs compared to other igneous rocks such as basalt and andesites. To better understand the interaction between REEs and soils, the nature of soils must be considered. In this paper, we discussed the distribution pattern of 232 Th and 238 U along with REEs in soil samples of weathered acid rock (granite and ryolite) collected from two prefectures of Japan: (1) Kobe city in Hyogo prefecture and (2) Mutsu city and Higashidori village in Aomori prefecture. (author)

Forest soil mineral weathering rates: use of multiple approaches

Science.gov (United States)

Randy K. Kolka; D.F. Grigal; E.A. Nater

1996-01-01

Knowledge of rates of release of base cations from mineral dissolution (weathering) is essential to understand ecosystem elemental cycling. Although much studied, rates remain enigmatic. We compared the results of four methods to determine cation (Ca + Mg + K) release rates at five forested soils/sites in the northcentral U.S.A. Our premise was that multiple...

The Impact of Organo-Mineral Complexation on Mineral Weathering in the Soil Zone under Unsaturated Conditions

Science.gov (United States)

Michael, H. A.; Tan, F.; Yoo, K.; Imhoff, P. T.

2017-12-01

While organo-mineral complexes can protect organic matter (OM) from biodegradation, their impact on soil mineral weathering is not clear. Previous bench-scale experiments that focused on specific OM and minerals showed that the adsorption of OM to mineral surfaces accelerates the dissolution of some minerals. However, the impact of natural organo-mineral complexes on mineral dissolution under unsaturated conditions is not well known. In this study, soil samples prepared from an undisturbed forest site were used to determine mineral weathering rates under differing conditions of OM sorption to minerals. Two types of soil samples were generated: 1) soil with OM (C horizon soil from 84-100cm depth), and 2) soil without OM (the same soil as in 1) but with OM removed by heating to 350°for 24 h). Soil samples were column-packed and subjected to intermittent infiltration and drainage to mimic natural rainfall events. Each soil sample type was run in duplicate. The unsaturated condition was created by applying gas pressure to the column, and the unsaturated chemical weathering rates during each cycle were calculated from the effluent concentrations. During a single cycle, when applying the same gas pressure, soils with OM retained more moisture than OM-removed media, indicating increased water retention capacity under the impact of OM. This is consistent with the water retention data measured by evaporation experiments (HYPROP) and the dew point method (WP4C Potential Meter). Correspondingly, silicon (Si) denudation rates indicated that dissolution of silicate minerals was 2-4 times higher in OM soils, suggesting that organo-mineral complexes accelerate mineral dissolution under unsaturated conditions. When combining data from all cycles, the results showed that Si denudation rates were positively related to soil water content: denundation rate increased with increasing water content. Therefore, natural mineral chemical weathering under unsaturated conditions, while

On the structure of space-time caustics

International Nuclear Information System (INIS)

Rosquist, K.

1983-01-01

Caustics formed by timelike and null geodesics in a space-time M are investigated. Care is taken to distinguish the conjugate points in the tangent space (T-conjugate points) from conjugate points in the manifold (M-conjugate points). It is shown that most nonspacelike conjugate points are regular, i.e. with all neighbouring conjugate points having the same degree of degeneracy. The regular timelike T-conjugate locus is shown to be a smooth 3-dimensional submanifold of the tangent space. Analogously, the regular null T-conjugate locus is shown to be a smooth 2-dimensional submanifold of the light cone in the tangent space. The smoothness properties of the null caustic are used to show that if an observer sees focusing in all directions, then there will necessarily be a cusp in the caustic. If, in addition, all the null conjugate points have maximal degree of degeneracy (as in the closed Friedmann-Robertson-Walker universes), then the space-time is closed. (orig.)

Hazardous E-waste and its impact on soil structure

Science.gov (United States)

Dharini, K.; Cynthia, J. Bernadette; Kamalambikai, B.; Sudar Celestina, J. P. Arul; Muthu, D.

2017-07-01

E-waste disposal has been a significant issue over the past few decades with the development of technology and the plethora of electronic products produced. The inclusive term E-Waste encapsulates various forms of electrical and electronical equipment which provides no value to the current owners and it is one among the fastest growing waste streams. E-Waste is a complex, non-biodegradable waste which is generally dumped in mountain like heaps. These wastes are said to have a large quantities of lead, cadmium, arsenic etc.it is mandatory to dispose such scrupulously since they have the ability to affect the soil and water parameters. Solid waste management is a blooming field which strives to reduce the accumulation of used electronic gadgets. Rainwater gets infiltrated through the e-waste landfill and it leaches through the soil which in turn reaches the groundwater directly thereby affecting the water intended for drinking and domestic purposes. This study focuses on the consequences of toxic waste by comparing the difference in properties of the soil structure prior to and after the e-waste landfill at various concentrations.

Influence of soil and hydrocarbon properties on the solvent extraction of high-concentration weathered petroleum from contaminated soils.

Science.gov (United States)

Sui, Hong; Hua, Zhengtao; Li, Xingang; Li, Hong; Wu, Guozhong

2014-05-01

Petroleum ether was used to extract petroleum hydrocarbons from soils collected from six oil fields with different history of exploratory and contamination. It was capable of fast removing 76-94 % of the total petroleum hydrocarbons including 25 alkanes (C11-C35) and 16 US EPA priority polycyclic aromatic hydrocarbons from soils at room temperature. The partial least squares analysis indicated that the solvent extraction efficiencies were positively correlated with soil organic matter, cation exchange capacity, moisture, pH, and sand content of soils, while negative effects were observed in the properties reflecting the molecular size (e.g., molecular weight and number of carbon atoms) and hydrophobicity (e.g., water solubility, octanol-water partition coefficient, soil organic carbon partition coefficient) of hydrocarbons. The high concentration of weathered crude oil at the order of 10(5) mg kg(-1) in this study was demonstrated adverse for solvent extraction by providing an obvious nonaqueous phase liquid phase for hydrocarbon sinking and increasing the sequestration of soluble hydrocarbons in the insoluble oil fractions during weathering. A full picture of the mass distribution and transport mechanism of petroleum contaminants in soils will ultimately require a variety of studies to gain insights into the dynamic interactions between environmental indicator hydrocarbons and their host oil matrix.

Soil reinforcement with recycled carpet wastes.

Science.gov (United States)

Ghiassian, Hossein; Poorebrahim, Gholamreza; Gray, Donald H

2004-04-01

A root or fibre-reinforced soil behaves as a composite material in which fibres of relatively high tensile strength are embedded in a matrix of relatively plastic soil. Shear stresses in the soil mobilize tensile resistance in the fibres, which in turn impart greater strength to the soil. A research project has been undertaken to study the influence of synthetic fibrous materials for improving the strength characteristics of a fine sandy soil. One of the main objectives of the project is to explore the conversion of fibrous carpet waste into a value-added product for soil reinforcement. Drained triaxial tests were conducted on specimens, which were prepared in a cylindrical mould and compacted at their optimum water contents. The main test variables included the aspect ratio and the weight percentage of the fibrous strips. The results clearly show that fibrous inclusions derived from carpet wastes improve the shear strength of silty sands. A model developed to simulate the effect of the fibrous inclusions accurately predicts the influence of strip content, aspect ratio and confining pressure on the shear strength of reinforced sand.

Semiclassical expansions on and near caustics

International Nuclear Information System (INIS)

Meetz, K.

1984-09-01

We show that the standard WKB expansion can be generalized so that it reproduces the behavior of the wave function on and near a caustic in two-dimensional space time. The expansion is related to the unfolding polynomials of the elementary catastrophes occurring in two dimensions: the fold and the cusp catastrophe. The method determines control parameters and transport coefficients in a self-consistent way from differential equations and does not refer to the asymptotic expansion of Feynman path integrals. The lowest order equations are solved explicitly in terms of the multivalued classical action. The result is a generalized semiclassical approximation on and beyond a caustic. (orig.)

Intensity and duration of chemical weathering: An example from soil clays of the southeastern Koolau Mountains, Oahu, Hawaii

Science.gov (United States)

Johnsson, Mark J.; Ellen, Stephen D.; McKittrick, Mary Anne

1993-01-01

Orographic precipitation on the southern flank of the southeastern Koolau Mountains produces a pronounced precipitation gradient. The corresponding gradient in the intensity of the chemical weathering environment provides an opportunity to address the effects of varying chemical weathering intensity on the composition of clay-size weathering products in soils developed on basalt. In addition, little-modified remnants of the constructional surface of the Koolau Volcano, isolated by stream dissection, remain as facets on the southern ends of the parallel ridges of the study area. By comparing clay mineralogy of soils developed on these older geomorphic surfaces with those developed on the younger sharp-crested ridges and steep side slopes, the effects of weathering duration on clay mineralogy can also be addressed.Soil clays in this part of the Koolau Mountains are mineralogically complex; principal phases include smectite, kaolinite, and halloysite, but pure end member phases are uncommon. Rather, most phases contain some amount of mixed layering. Smectite may contain small (Volcano are markedly more leached than those from younger landscapes in the same precipitation regime. Although smectite may be present, kaolinite is the dominant phase, and accumulations of Fe and Ti occur in the uppermost soil levels. Enrichment of Zr and Ti in these soils, as compared to concentrations in the original basaltic parent material, indicates that as much as 75% of the parent material has been lost. Thus weathering duration may affect soil clay composition in the same way as weathering intensity.Because smectite and halloysite are expandable clay minerals, their presence in soils may decrease slope stability and influence the nature of slope processes. Soil avalanches occur on steep slopes throughout the study area, whereas slow-moving landslides appear to be restricted to gentler slopes in drier parts of the study area where smectite is abundant. The clay mineralogy of soils thus

Microbial control on decomposition of radionuclides-containing oily waste in soil

Science.gov (United States)

Selivanovskaya, Svetlana; Galitskaya, Polina

2014-05-01

The oily wastes are formed annually during extraction, refinement, and transportation of the oil and may cause pollution of the environment. These wastes contain different concentrations of waste oil (40-60%), waste water (30-90%), and mineral particles (5-40%). Some oily wastes also contain naturally occurring radionuclides which were incorporated by water that was pumped up with the oil. For assessment of the hazard level of waste treated soil, not only measurements of contaminants content are needed, because bioavailability of oily components varies with hydrocarbon type, and soil properties. As far as namely microbial communities control the decomposition of organic contaminants, biological indicators have become increasingly important in hazard assessment and the efficiency of remediation process. In this study the decomposition of radionuclides-containing oily waste by soil microbial communities were estimated. Waste samples collected at the Tikchonovskii petroleum production yard (Tatarstan, Russia) were mixed with Haplic greyzem soil at ratio 1:4 and incubated for 120 days. During incubation period, the total hydrocarbon content of the soil mixed with the waste reduced from 156 ± 48 g kg-1 to 54 ± 8 g kg-1 of soil. The concentrations of 226Ra and 232Th were found to be 643 ± 127, 254 ± 56 Bq kg-1 and not changed significantly during incubation. Waste application led to a soil microbial biomass carbon decrease in comparison to control (1.9 times after 1 day and 1.3 times after 120 days of incubation). Microbial respiration increased in the first month of incubation (up to 120% and 160% of control after 1 and 30 days, correspondingly) and decreased to the end of incubation period (74% of control after 120 days). Structure of bacterial community in soil and soil/waste mixture was estimated after 120 days of incubation using SSCP method. The band number decreased in contaminated soil in comparison to untreated soil. Besides, several new dominant DNA

Controls on carbon storage and weathering in volcanic ash soils across a climate gradient on Mauna Kea, Hawaii

Science.gov (United States)

Kramer, M. G.; Chadwick, O.

2017-12-01

Volcanic ash soils retain the largest and most persistent soil carbon pools of any ecosystem. However, the mechanisms governing soil carbon accumulation and weathering during initial phases of weathering are not well understood. We examined soil organic matter dynamics and weathering across a high altitude (3563 - 3013 m) 20 ky climate gradient on Mauna Kea in Hawaii. Four elevation sites were selected ( 250-500 mm rainfall) which range from arid-periglacial to sites which contain a mix of shrubs and grasses. At each site, between 2-3 pits were dug and major diagnostic horizons down to bedrock (in-tact lava) were sampled. Soils were analyzed for particle size, organic C and N, soil pH, exchangeable cations, base saturation, NaF pH, phosphorous sorption and bulk elements. Mass loss and pedogenic metal accumulation (hydroxlamine Fe, Al and Si extractions) were used to measure extent of weathering, leaching, changes in soil mineralogy and carbon accumulation with the short-range-ordered (SRO) minerals. Reactive-phase (SRO) minerals show a general trend of increasing abundance through the soil depth profile with increasing rainfall. However carbon accumulation patterns across the climate gradient are largely decoupled from these trends. The results suggest that after 20ky, pedogenic processes have altered the nature and composition of the volcanic ash such that it is capable of retaining soil C even where organic acid influences from plant material and leaching from rainfall is severely limited. Comparisons with lower elevation soils on Mauna Kea and other moist mesic (2500mm rainfall) sites on Hawaii suggest that these soils have reached only between 1-15 % of their capacity to retain carbon. Our results suggest that in low rainfall and a cold climate, after 20ky, weathering has advanced but is decoupled from soil carbon accumulation patterns and the associated influence of vegetation on soil development. Changes in soil carbon composition and amount across the entire

Waste conditioning technology of radiocontaminated soil

International Nuclear Information System (INIS)

Chen Dahua; Wang Xiaoli; Chen Xin

2012-01-01

A special conditioning way for low level soil contaminated by 241 Am was discussed. Firstly, the contaminated soil was condensed in package container (200 L drum) by 20 t pressing machine. The contaminated soil was pressed from loose state to compaction state, and the volume reduction rate was from 1.1 to 1.4. Secondly, cement with thickness of 10 cm to 15 cm was poured on the package container for sealing. Thus, a cement sealing member was made up by contaminated soil and it could be described as normal solid waste. Finally, taking the cement sealing member as conditioning object, using Ⅶ steel trunk as package container and cement conditioning, Ⅶ steel trunk package was got. Through radiation monitoring, the Ⅶ steel trunk package can satisfy the transport requirement of radiation waste. Also, it can satisfy the accept and disposal requirements of national repository. (authors)

What's weathering? Mineralogy and field leach studies in mine waste, Leadville and Montezuma mining districts, Colorado

Science.gov (United States)

Diehl, S.F.; Hageman, Phil L.; Smith, Kathleen S.

2006-01-01

Weathering is important in the development of rock fabrics that control porosity in mine-waste materials, and in turn, porosity affects metal transport through and from mine-waste piles into watersheds. Mine-waste piles are dynamic physical and chemical systems as evidenced by remnant Fe-oxide boxwork structures after sulfide minerals, development of alteration rinds and etch pits on grains, and precipitation of secondary minerals under low temperature conditions. These microscale changes in the mine-waste materials are the result of partial to total dissolution of sulfide and other minerals. Mine-waste materials from the Dinero, Lower Chatauqua, and Saints John sites, Leadville and Montezuma mining districts, Colorado, exhibit rock fabrics that indicate that weathering products, e.g., Fe oxyhydroxides, jarosite, and clays, have been transported in suspension through the waste piles and deposited in voids and as coatings on rock fragments. Microscale characterization of weathered, partially dissolved minerals lends insight into the source of leachable metals in these mine-waste sites. Mineralogic studies show that galena in the Lower Chatauqua waste is enriched in Ag. Qualitative and semiquantitative microanalysis of weathered, altered galena grains from all three sites show that the Ag-bearing galena is more susceptible to dissolution. It is not surprising, then, that solutions experimentally leached from Lower Chatauqua waste are higher in Pb (2310 ppb) compared to leachates from the Dinero (31 ppb) and Saints John (1360 ppb) wastes. The mobility of metals is increased at acidic pH. Using the USGS Field Leach Test protocol, leachate derived from the Dinero waste has a pH of 3 and high concentrations of Al (443 ppb), Fe (441 ppb), and Zn (7970 ppb). Leachate from Sts. John tailings has a pH about 4 and high concentrations of Mn (1520 ppb), Zn (2240 ppb), and Pb (1360 ppb). Leachate from the Lower Chatauqua waste has an intermediate pH of 5, but in addition to the

Tracking nanoparticles in an optical microscope using caustics

International Nuclear Information System (INIS)

Patterson, Eann A; Whelan, Maurice P

2008-01-01

An elegant method is proposed and demonstrated for tracking the location and movement of nanoparticles in an optical microscope using the optical phenomenon of caustics. A simple and reversible adjustment to the microscope generates caustics several orders of magnitude larger than the particles. The method offers a simple and relatively inexpensive method for visualizing such phenomena as the formation of self-assembled monolayers and the interaction of nanoparticles with chemically functionalized surfaces

Tracking nanoparticles in an optical microscope using caustics

Energy Technology Data Exchange (ETDEWEB)

Patterson, Eann A [Department of Mechanical Engineering, Michigan State University, East Lansing, MI 48824 (United States); Whelan, Maurice P [Nanotechnology and Molecular Imaging Unit, Institute for Health and Consumer Protection, European Commission DG Joint Research Center, 21021 Ispra (Vatican City State, Holy See,) (Italy)

2008-03-12

An elegant method is proposed and demonstrated for tracking the location and movement of nanoparticles in an optical microscope using the optical phenomenon of caustics. A simple and reversible adjustment to the microscope generates caustics several orders of magnitude larger than the particles. The method offers a simple and relatively inexpensive method for visualizing such phenomena as the formation of self-assembled monolayers and the interaction of nanoparticles with chemically functionalized surfaces.

Behavior of granular rubber waste tire reinforced soil for application in geosynthetic reinforced soil wall

Directory of Open Access Journals (Sweden)

G. G. D. RAMIREZ

Full Text Available AbstractLarge quantities of waste tires are released to the environment in an undesirable way. The potential use of this waste material in geotechnical applications can contribute to reducing the tire disposal problem and to improve strength and deformation characteristics of soils. This paper presents a laboratory study on the effect of granular rubber waste tire on the physical properties of a clayey soil. Compaction tests using standard effort and consolidated-drained triaxial tests were run on soil and mixtures. The results conveyed an improvement in the cohesion and the angle of internal friction the clayey soil-granular rubber mixture, depending on the level of confining stress. These mixtures can be used like backfill material in soil retaining walls replacing the clayey soil due to its better strength and shear behavior and low unit weight. A numerical simulation was conducted for geosynthetic reinforced soil wall using the clayey soil and mixture like backfill material to analyzing the influence in this structure.

Autogenous Tumbling Media Assessment to Clean Weathered Surfaces of Waste-Rock Particles from a Basalt Quarry

Directory of Open Access Journals (Sweden)

Baran Tufan

2015-06-01

Full Text Available In this study, the optimum feed composition in autogenous tumbling of basalt waste-rock particles to clean their weathered surface was determined. The weathered surfaces of basalt are generally cut out consequent to extraction of basalt columns in quarry operations. The inefficiently cut out portions of basalt cause formation of huge quarry waste dumps causing visual pollution on roadsides. Mixtures of different particle size fractions of basalt waste-rock particles were experimented to achieve the optimum feed material composition. The minimum loss of commercially available basalt particles and maximum clear surface was intended. The results were compared with respect to weight loss (% and reflectance values of used and generated samples.

Removal of overburden soils from buried waste sites

International Nuclear Information System (INIS)

Rice, P.M.

1994-01-01

Transuranic (TRU) waste buried in pits and trenches is covered with a soil cap, or overburden, to shed water. During retrieval operations, the overburden (expected to be clean) must be removed carefully to avoid breaching the soil/waste matrix within a pit or trench and to confine any possible local spot contamination. This necessitates removal in precise (7.6- to 15.25-cm) increments with a high degree of accuracy. In addition, during overburden removal the overburden must be characterized to a depth that exceeds each cut of soil. A field demonstration was conducted to evaluate a technology for removing overburden soils a the Radioactive Waste Management Complex (RWMC), Subsurface Disposal Area (SDA) at the Idaho National Engineering Laboratory (INEL). The demonstration evaluated equipment performance and techniques for removing overburden soil and controlling contamination and dust. To evaluate the performance of these techniques during removal operations, personnel took air particulate samples, physical measurements of the soil cuts, maneuverability measurements, and rate of soil removal data. The overburden was spiked at specific locations and depths with rare earth tracers to provide a medium for evaluating samples. Analysis to determine the precision and accuracy of the soil removal, amount of dust generated, and potential spread of contamination was performed

Partitioning of Tank Waste Sludge in a 5-cm Centrifugal Contactor Under Caustic-Side Solvent Extraction Conditions

International Nuclear Information System (INIS)

Birdwell, Jr. J.F.

2001-01-01

A test program has been performed to evaluate the effect of solids on the hydraulic performance of a 5-cm centrifugal contactor under conditions present in the extraction section of the Caustic-Side Solvent Extraction (CSSX) process. In addition to determining if the ability to separate the aqueous and organic phases is affected by the presence of solids in a feed solution, the extent to which solids are accumulated in the contactor was also assessed. The reported task was motivated by the need to determine if removal of cesium from Savannah River Site tank waste can be performed using a contactor-based CSSX process without first removing sludge that is suspended in the feed solution. The ability to pass solids through the CSSX process could facilitate placement of CSSX upstream of a process in which alpha-decaying actinides and strontium are removed from the waste stream by precipitation with monosodium titanate (MST). This relative placement of the CSSX and MST processes is desirable because removal of cesium would greatly reduce the activity level of the feed stream to the MST process, thereby reducing the level of shielding needed and mitigating remote maintenance design features of MST equipment. Both results would significantly reduce the cost of the Salt Processing Project. Test results indicate conclusively that a large fraction of suspended sludge that enters the centrifugal contactor remains inside. It is expected that extended operation would result in continued accumulation of solids and that hydraulic performance would be adversely affected. Results also indicate that a fraction of the solids partitions to the phase boundary and could affect phase separation as contactor operations progress

Characteristics of wastes and soils which affect transport of radionuclides through the soil and their relationship to waste management. Annual report FY78

International Nuclear Information System (INIS)

Polzer, W.L.; Fowler, E.B.; Essington, E.H.

1979-04-01

Soil samples were collected from Beatty, NV, the University of California, Los Angeles/University of California, Berkeley (UCLA/UCB) project, California and Nebraska. Results of waste/soil interaction studies indicate that waste radionuclides can be categorized into three broad forms; filterable (insoluble) and sorbable and nonsorbable (soluble). The relative distribution of the three depends on the storage time of the waste and on the soil which is interacted with the waste. In the filterable (insoluble) fraction the radionuclides are associated with both organic and inorganic particulates. The primary inorganic particulate was identified as calcium carbonate. The soluble nonsorbable waste radionuclides possess a negative charge with the exception of 137 Cs; that species is positively charged. The presence of negatively charged species is attributed to complexing with either carbonate or chelating compounds. Changes in the soluble fraction of waste radionuclides on storage of waste are attributed in part to the dissolution or precipitation of calcium carbonate and perhaps the degradation of organic material or growth of microorganisms in the waste. 11 figures, 31 tables

Soil washing results for mixed waste pond soils at Hanford

International Nuclear Information System (INIS)

Gerber, M.A.; Freeman, H.D.; Baker, E.G.; Riemath, W.F.

1991-01-01

Soil washing technology was assessed as a means for remediating soil contaminated with mixed wastes primarily composed of heavy metals and radionuclides. The soils at the US Department of Energy's Hanford Site are considered suitable for soil washing because of their relatively low quantities of silt and clay. However, in a limited number of soil washing experiments using soils from different locations in the north pond of the 300 Area, the degree of decontamination achieved for the coarse fraction of the soil varied considerably. Part of this variation appears to be due to the presence of a discrete layer of contaminated sediment found in some of the samples

[Use of Leersia hexandra (Poaceae) for soil phytoremediation in soils contaminated with fresh and weathered oil].

Science.gov (United States)

Arias-Trinidad, Alfredo; Rivera-Cruz, María del Carmen; Roldán-Garrigós, Antonio; Aceves-Navarro, Lorenzo Armando; Quintero-Lizaola, Roberto; Hernández-Guzmán, Javier

2017-03-01

The oil industry has generated chronic oil spills and their accumulation in wetlands of the state of Tabasco, in Southeastern Mexico. Waterlogging is a factor that limits the use of remediation technologies because of its high cost and low levels of oil degradation. However, Leersia hexandra is a grass that grows in these contaminated areas with weathered oil. The aim of the study was to evaluate the bacteria density, plant biomass production and phytoremediation of L. hexandra in contaminated soil. For this, two experiments in plastic tunnel were performed with fresh (E1) and weathered petroleum (E2) under waterlogging experimental conditions. The E1 was based on eight doses: 6 000, 10 000, 30 000, 60 000, 90 000, 120 000, 150 000 and 180 000 mg.kg-1 dry basis (d. b.) of total petroleum hydrocarbons fresh (TPH-F), and the E2, that evaluated five doses: 14 173, 28 400, 50 598, 75 492 and 112 142 mg. kg-1 d. b. of total petroleum hydrocarbons weathered (TPH-W); a control treatment with 2 607 mg.kg-1 d. b. was used. Each experiment, with eight replicates per treatment, evaluated after three and six months: a) microbial density of total free-living nitrogen-fixing bacteria (NFB) of Azospirillum (AZP) and Azotobacter group (AZT), for viable count in serial plate; b) dry matter production (DMP), quantified gravimetrically as dry weight of L. hexandra; and c) the decontamination percentage of hydrocarbons (PDH) by Soxhlet extraction. In soil with TPH-F, the NFB, AZP y AZT populations were stimulated five times more than the control both at the three and six months; however, concentrations of 150 000 and 180 000 mg.kg-1 d. b. inhibited the bacterial density between 70 and 89 %. Likewise, in soil with TPH-W, the FNB, AZP and AZT inhibitions were 90 %, with the exception of the 14 173 mg.kg-1 d. b. treatment, which stimulated the NFB and AZT in 2 and 0.10 times more than the control, respectively. The DMP was continued at the six months in the experiments, with values of 63

Preliminary results of an attempt to provide soil moisture datasets in order to verify numerical weather prediction models

International Nuclear Information System (INIS)

Cassardo, C.; Loglisci, N.

2005-01-01

In the recent years, there has been a significant growth in the recognition of the soil moisture importance in large-scale hydrology and climate modelling. Soil moisture is a lower boundary condition, which rules the partitioning of energy in terms of sensible and latent heat flux. Wrong estimations of soil moisture lead to wrong simulation of the surface layer evolution and hence precipitations and cloud cover forecasts could be consequently affected. This is true for large scale medium-range weather forecasts as well as for local-scale short range weather forecasts, particularly in those situations in which local convection is well developed. Unfortunately; despite the importance of this physical parameter there are only few soil moisture data sets sparse in time and in space around in the world. Due to this scarcity of soil moisture observations, we developed an alternative method to provide soil moisture datasets in order to verify numerical weather prediction models. In this paper are presented the preliminary results of an attempt to verify soil moisture fields predicted by a mesoscale model. The data for the comparison were provided by the simulations of the diagnostic land surface scheme LSPM (Land Surface Process Model), widely used at the Piedmont Regional Weather Service for agro-meteorological purposes. To this end, LSPM was initialized and driven by Synop observations, while the surface (vegetation and soil) parameter values were initialized by ECOCLIMAP global dataset at 1km 2 resolution

Updated global soil map for the Weather Research and Forecasting model and soil moisture initialization for the Noah land surface model

Science.gov (United States)

DY, C. Y.; Fung, J. C. H.

2016-08-01

A meteorological model requires accurate initial conditions and boundary conditions to obtain realistic numerical weather predictions. The land surface controls the surface heat and moisture exchanges, which can be determined by the physical properties of the soil and soil state variables, subsequently exerting an effect on the boundary layer meteorology. The initial and boundary conditions of soil moisture are currently obtained via National Centers for Environmental Prediction FNL (Final) Operational Global Analysis data, which are collected operationally in 1° by 1° resolutions every 6 h. Another input to the model is the soil map generated by the Food and Agriculture Organization of the United Nations - United Nations Educational, Scientific and Cultural Organization (FAO-UNESCO) soil database, which combines several soil surveys from around the world. Both soil moisture from the FNL analysis data and the default soil map lack accuracy and feature coarse resolutions, particularly for certain areas of China. In this study, we update the global soil map with data from Beijing Normal University in 1 km by 1 km grids and propose an alternative method of soil moisture initialization. Simulations of the Weather Research and Forecasting model show that spinning-up the soil moisture improves near-surface temperature and relative humidity prediction using different types of soil moisture initialization. Explanations of that improvement and improvement of the planetary boundary layer height in performing process analysis are provided.

Can conservation agriculture improve phosphorus (P) availability in weathered soils? Effects of tillage and residue management on soil P status after 9 years in a Kenyan Oxisol

NARCIS (Netherlands)

Margenot, Andrew; Paul, B.K.; Pulleman, M.M.; Parikh, Sanjai; Fonte, Steven J.

2017-01-01

The widespread promotion of conservation agriculture (CA) in regions with weathered soils prone to phosphorus (P) deficiency merits explicit consideration of its effect on P availability. A long-term CA field trial located on an acid, weathered soil in western Kenya was evaluated for effects of

Olivine weathering in soil, and its effects on growth and nutrient uptake in Ryegrass (Lolium perenne L.: a pot experiment.

Directory of Open Access Journals (Sweden)

Hein F M ten Berge

Full Text Available Mineral carbonation of basic silicate minerals regulates atmospheric CO(2 on geological time scales by locking up carbon. Mining and spreading onto the earth's surface of fast-weathering silicates, such as olivine, has been proposed to speed up this natural CO(2 sequestration ('enhanced weathering'. While agriculture may offer an existing infrastructure, weathering rate and impacts on soil and plant are largely unknown. Our objectives were to assess weathering of olivine in soil, and its effects on plant growth and nutrient uptake. In a pot experiment with perennial ryegrass (Lolium perenne L., weathering during 32 weeks was inferred from bioavailability of magnesium (Mg in soil and plant. Olivine doses were equivalent to 1630 (OLIV1, 8150, 40700 and 204000 (OLIV4 kg ha(-1. Alternatively, the soluble Mg salt kieserite was applied for reference. Olivine increased plant growth (+15.6% and plant K concentration (+16.5% in OLIV4. At all doses, olivine increased bioavailability of Mg and Ni in soil, as well as uptake of Mg, Si and Ni in plants. Olivine suppressed Ca uptake. Weathering estimated from a Mg balance was equivalent to 240 kg ha(-1 (14.8% of dose, OLIV1 to 2240 kg ha(-1 (1.1%, OLIV4. This corresponds to gross CO(2 sequestration of 290 to 2690 kg ha(-1 (29 10(3 to 269 10(3 kg km(-2. Alternatively, weathering estimated from similarity with kieserite treatments ranged from 13% to 58% for OLIV1. The Olsen model for olivine carbonation predicted 4.0% to 9.0% weathering for our case, independent of olivine dose. Our % values observed at high doses were smaller than this, suggesting negative feedbacks in soil. Yet, weathering appears fast enough to support the 'enhanced weathering' concept. In agriculture, olivine doses must remain within limits to avoid imbalances in plant nutrition, notably at low Ca availability; and to avoid Ni accumulation in soil and crop.

Iron and silicon isotope behaviour accompanying weathering in Icelandic soils, and the implications for iron export from peatlands

Science.gov (United States)

Opfergelt, S.; Williams, H. M.; Cornelis, J. T.; Guicharnaud, R. A.; Georg, R. B.; Siebert, C.; Gislason, S. R.; Halliday, A. N.; Burton, K. W.

2017-11-01

Incipient warming of peatlands at high latitudes is expected to modify soil drainage and hence the redox conditions, which has implications for Fe export from soils. This study uses Fe isotopes to assess the processes controlling Fe export in a range of Icelandic soils including peat soils derived from the same parent basalt, where Fe isotope variations principally reflect differences in weathering and drainage. In poorly weathered, well-drained soils (non-peat soils), the limited Fe isotope fractionation in soil solutions relative to the bulk soil (Δ57Fesolution-soil = -0.11 ± 0.12‰) is attributed to proton-promoted mineral dissolution. In the more weathered poorly drained soils (peat soils), the soil solutions are usually lighter than the bulk soil (Δ57Fesolution-soil = -0.41 ± 0.32‰), which indicates that Fe has been mobilised by reductive mineral dissolution and/or ligand-controlled dissolution. The results highlight the presence of Fe-organic complexes in solution in anoxic conditions. An additional constraint on soil weathering is provided by Si isotopes. The Si isotope composition of the soil solutions relative to the soil (Δ30Sisolution-soil = 0.92 ± 0.26‰) generally reflects the incorporation of light Si isotopes in secondary aluminosilicates. Under anoxic conditions in peat soils, the largest Si isotope fractionation in soil solutions relative to the bulk soil is observed (Δ30Sisolution-soil = 1.63 ± 0.40‰) and attributed to the cumulative contribution of secondary clay minerals and amorphous silica precipitation. Si supersaturation in solution with respect to amorphous silica is reached upon freezing when Al availability to form aluminosilicates is limited by the affinity of Al for metal-organic complexes. Therefore, the precipitation of amorphous silica in peat soils indirectly supports the formation of metal-organic complexes in poorly drained soils. These observations highlight that in a scenario of decreasing soil drainage with

Study of arsenopyrite weathering products in mine wastes from abandoned tungsten and tin exploitations

Energy Technology Data Exchange (ETDEWEB)

Murciego, A. [Department of Geology, Plza. de los Caidos s/n. Salamanca University, 37008 Salamanca (Spain); Alvarez-Ayuso, E., E-mail: esther.alvarez@irnasa.csic.es [Department of Environmental Geochemistry, IRNASA (CSIC), Apdo. 257, 37071 Salamanca (Spain); Pellitero, E. [Department of Geology, Plza. de los Caidos s/n. Salamanca University, 37008 Salamanca (Spain); Rodriguez, M.A. [Faculty of Sciences, Crystallography and Mineralogy Area, Avd. Elvas s/n. Extremadura University, 06071 Badajoz (Spain); Garcia-Sanchez, A. [Department of Environmental Geochemistry, IRNASA (CSIC), Apdo. 257, 37071 Salamanca (Spain); Tamayo, A.; Rubio, J.; Rubio, F. [Ceramic and Glass Institute (CSIC), c/Kelsen, 5, 28049 Cantoblanco, Madrid (Spain); Rubin, J. [Material Science Institute of Aragon, CSIC-Zaragoza University, c/Maria de Luna 3, 50009 Zaragoza (Spain)

2011-02-15

Arsenopyrite-rich wastes from abandoned tungsten and tin exploitations were studied to determine the composition and characteristics of the secondary phases formed under natural weathering conditions so as to assess their potential environmental risk. Representative weathered arsenopyrite-bearing rock wastes collected from the mine dumps were analysed using the following techniques: X-ray powder diffraction (XRD) analysis, polarizing microscopy analysis, electron microprobe analysis (EMPA) and microRaman and Moessbauer spectroscopies. Scorodite, pharmacosiderite and amorphous ferric arsenates (AFA) with Fe/As molar ratios in the range 1.2-2.5 were identified as secondary arsenic products. The former showed to be the most abundant and present in the different studied mining areas. Its chemical composition showed to vary in function of the original surrounding rock mineralogy in such a way that phosphoscorodite was found as the mineral variety present in apatite-containing geoenvirons. Other ever-present weathering phases were goethite and hydrous ferric oxides (HFO), displaying, respectively, As retained amounts about 1 and 20% (expressed as As{sub 2}O{sub 5}). The low solubility of scorodite, the relatively low content of AFA and the formation of compounds of variable charge, mostly of amorphous nature, with high capacity to adsorb As attenuate importantly the dispersion of this element into the environment from these arsenopyrite-bearing wastes.

Study of arsenopyrite weathering products in mine wastes from abandoned tungsten and tin exploitations

International Nuclear Information System (INIS)

Murciego, A.; Alvarez-Ayuso, E.; Pellitero, E.; Rodriguez, M.A.; Garcia-Sanchez, A.; Tamayo, A.; Rubio, J.; Rubio, F.; Rubin, J.

2011-01-01

Arsenopyrite-rich wastes from abandoned tungsten and tin exploitations were studied to determine the composition and characteristics of the secondary phases formed under natural weathering conditions so as to assess their potential environmental risk. Representative weathered arsenopyrite-bearing rock wastes collected from the mine dumps were analysed using the following techniques: X-ray powder diffraction (XRD) analysis, polarizing microscopy analysis, electron microprobe analysis (EMPA) and microRaman and Moessbauer spectroscopies. Scorodite, pharmacosiderite and amorphous ferric arsenates (AFA) with Fe/As molar ratios in the range 1.2-2.5 were identified as secondary arsenic products. The former showed to be the most abundant and present in the different studied mining areas. Its chemical composition showed to vary in function of the original surrounding rock mineralogy in such a way that phosphoscorodite was found as the mineral variety present in apatite-containing geoenvirons. Other ever-present weathering phases were goethite and hydrous ferric oxides (HFO), displaying, respectively, As retained amounts about 1 and 20% (expressed as As 2 O 5 ). The low solubility of scorodite, the relatively low content of AFA and the formation of compounds of variable charge, mostly of amorphous nature, with high capacity to adsorb As attenuate importantly the dispersion of this element into the environment from these arsenopyrite-bearing wastes.

Minimum Additive Waste Stabilization (MAWS), Phase I: Soil washing final report

International Nuclear Information System (INIS)

1995-08-01

As a result of the U.S. Department of Energy's environmental restoration and technology development activities, GTS Duratek, Inc., and its subcontractors have demonstrated an integrated thermal waste treatment system at Fernald, OH, as part the Minimum Additive Waste Stabilization (MAWS) Program. Specifically, MAWS integrates soil washing, vitrification of mixed waste streams, and ion exchange to recycle and remediate process water to achieve, through a synergistic effect, a reduction in waste volume, increased waste loading, and production of a durable, leach-resistant, stable waste form suitable for disposal. This report summarizes the results of the demonstration/testing of the soil washing component of the MAWS system installed at Fernald (Plant 9). The soil washing system was designed to (1) process contaminated soil at a rate of 0.25 cubic yards per hour; (2) reduce overall waste volume and provide consistent-quality silica sand and contaminant concentrates as raw material for vitrification; and (3) release clean soil with uranium levels below 35 pCi/g. Volume reductions expected ranged from 50-80 percent; the actual volume reduction achieved during the demonstration reached 66.5 percent. The activity level of clean soil was reduced to as low as 6 pCi/g from an initial average soil activity level of 17.6 pCi/g (the highest initial level of soil provided for testing was 41 pCi/g). Although the throughput of the soil washing system was inconsistent throughout the testing period, the system was online for sufficient periods to conclude that a rate equivalent to 0.25 cubic yards per hour was achieved

Adjustment of corn nitrogen in-season fertilization based on soil texture and weather conditions: a Meta-analysis of North American trials

Science.gov (United States)

Soil properties and weather conditions are known to affect soil nitrogen (N) availability and plant N uptake. However, studies examining N response as affected by soil and weather sometimes give conflicting results. Meta-analysis is a statistical method for estimating treatment effects in a series o...

Influence of industrial solid waste addition on properties of soil-cement bricks

Directory of Open Access Journals (Sweden)

F. B. Siqueira

Full Text Available Abstract The reuse of pollutant solid wastes produced in distinct industrial activities (avian eggshell waste and welding flux slag waste as a source of alternative raw material for producing soil-cement bricks for civil construction was investigated. Soil-cement bricks containing up to 30 wt% of industrial solid waste were uniaxially pressed and cured for 28 days. Special emphasis is given on the influence of solid waste addition on the technical properties (as such volumetric shrinkage, water absorption, bulk density, durability, and compressive strength, microstructure and mineral phases of soil-cement bricks. Microstructural evolution was evaluated via confocal microscopy. The experimental results showed that the solid wastes behave as charge material and influenced both technical properties and microstructure of the soil-cement bricks. It was found that up to 15 wt% of welding flux slag waste and up to 30 wt% of avian eggshell waste could be added into the soil-cement bricks for use as building material.

Stress corrosion cracking of duplex stainless steels in caustic solutions

Science.gov (United States)

Bhattacharya, Ananya

Duplex stainless steels (DSS) with roughly equal amount of austenite and ferrite phases are being used in industries such as petrochemical, nuclear, pulp and paper mills, de-salination plants, marine environments, and others. However, many DSS grades have been reported to undergo corrosion and stress corrosion cracking in some aggressive environments such as chlorides and sulfide-containing caustic solutions. Although stress corrosion cracking of duplex stainless steels in chloride solution has been investigated and well documented in the literature but the SCC mechanisms for DSS in caustic solutions were not known. Microstructural changes during fabrication processes affect the overall SCC susceptibility of these steels in caustic solutions. Other environmental factors, like pH of the solution, temperature, and resulting electrochemical potential also influence the SCC susceptibility of duplex stainless steels. In this study, the role of material and environmental parameters on corrosion and stress corrosion cracking of duplex stainless steels in caustic solutions were investigated. Changes in the DSS microstructure by different annealing and aging treatments were characterized in terms of changes in the ratio of austenite and ferrite phases, phase morphology and intermetallic precipitation using optical micrography, SEM, EDS, XRD, nano-indentation and microhardness methods. These samples were then tested for general and localized corrosion susceptibility and SCC to understand the underlying mechanisms of crack initiation and propagation in DSS in the above-mentioned environments. Results showed that the austenite phase in the DSS is more susceptible to crack initiation and propagation in caustic solutions, which is different from that in the low pH chloride environment where the ferrite phase is the more susceptible phase. This study also showed that microstructural changes in duplex stainless steels due to different heat treatments could affect their SCC

Interactions of radioactive wastes with soils. A review, October 1976-May 1979

International Nuclear Information System (INIS)

Fowler, E.B.; Essington, E.H.; Polzer, W.L.

1979-12-01

Retention of waste radionuclides by four soils of different types was determined using the batch and column methods. Raw and treated liquid wastes from a large laboratory complex were used. Three fractions identified in each waste were (1) insoluble, (2) soluble and sorbable by soil, and (3) soluble but nonsorbable by soil. The soluble fraction ( 137 Cs was retained by all soils. Plutonium isotopes and 241 Am were least retained by the soils; uranium isotope retention was intermediate. Reaction of a Fuquay soil with the insoluble fraction of the waste resulted in a net dissolution of Pu and Am. Two of the factors investigated that could influence the degree of retention by the soil were (1) charge on the radionuclide in solution, and (2) degree of calcium carbonate saturation. Retention of radionuclides by the soils occurs through ion exchange, occlusion in calcium carbonate precipitates, precipitation of aluminum, and filtration of particulates from the liquid wastes

Test report - 241-AN-274 Caustic Pump Control Building

International Nuclear Information System (INIS)

Paintner, G.P.

1995-05-01

This Acceptance Test Report documents the test results of test procedure WHC-SD-WM-ATP-135 'Acceptance Test Procedure for the 241-AN- 274 Caustic Pump Control Building.' The objective of the test was to verify that the 241-AN-274 Caustic Pump Control Building functions properly based on design specifications per applicable H-2-85573 drawings and associated ECN's. The objective of the test was met

Retention of phosphorus in highly weathered soils under a lowland Amazonian forest ecosystem

Science.gov (United States)

M. E. McGroddy; W. L. Silver; Jr. de Oliveira; W. Z. de Mello; M. Keller

2008-01-01

The low available phosphorus (P) pools typical of highly weathered tropical forest soils are thought to result from a combination of export of phosphorus via erosion and leaching as well as chemical reactions resulting in physically and chemically protected P compounds. Despite the low apparent P availability, these soils support some of the highest terrestrial net...

Soil Fertility and Electrical Conductivity Affected by Organic Waste Rates and Nutrient Inputs

Directory of Open Access Journals (Sweden)

Davi Lopes do Carmo

2016-01-01

Full Text Available ABSTRACT The composition of organic waste (OW and its effect on soil processes may change soil fertility and electrical conductivity (EC. The side effects of waste use in crop fertilization are poorly understood for Brazilian soils. This study examined the effect of the addition of 15 different organic wastes to Oxisols and a Neosol on pH, base saturation, EC, cation exchange capacity (CEC at pH 7, and the availability of Al, macro (P, K, Ca2+, Mg2+ and S and micronutrients (B, Fe2+, Mn2+, Cu2+ and Zn2+. Soil samples (150 g were treated with chicken, pig, horse, cattle, and quail manures, sewage sludge 1 and 2, eucalyptus sawdust, plant substrate, coconut fiber, pine bark, coffee husk, peat, limed compost, and biochar. Wastes were added considering a fixed amount of C (2 g kg-1, which resulted in waste rates ranging from 2.5 to 25.6 Mg ha-1. The soil-waste mixtures were incubated for 330 days in laboratory conditions. The waste liming or acidification values were soil-dependent. The use of some manures and compost increased the pH to levels above of those considered adequate for plant growth. The soil EC was slightly increased in the Neosol and in the medium textured Oxisol, but it was sharply changed (from 195 to 394 µS cm-1 by the addition of organic wastes in the clayey Oxisol, although the EC values were below the range considered safe for plant growth. Changes in the soil availability of P, K+, Ca2+ and Zn2+ were highly related to the inputs of these nutrients by the wastes, and other factors in soil changed due to waste use. Organic waste use simultaneously affects different soil fertility attributes; thus, in addition to the target nutrient added to the soil, the soil acidity buffering capacity and the waste liming and agronomic value must be taken into account in the waste rate definition.

Soil washing results for mixed waste pond soils at Hanford

International Nuclear Information System (INIS)

Gerber, M.A.

1991-09-01

Soil washing technology was assessed as a means for remediating soil contaminated with mixed wastes primarily composed of heavy metals and radionuclides. The soils at the US Department of Energy's Hanford Site are considered suitable for soil washing because of their relatively low quantities of silt and clay. However, in a limited number of soil washing experiments using soils from different locations in the north pond of the 300 Area, the degree of decontamination achieved for the coarse fraction of the soil varied considerably. Part of this variation appears to be due to the presence of a discrete layer of contaminated sediment found in some of the samples. 7 refs., 2 figs., 4 tabs

Challenges of E-Waste pollution to soil environments in Nigeria - A ...

African Journals Online (AJOL)

Challenges of E-Waste pollution to soil environments in Nigeria - A Review. ... of ewaste on the environment (including the soil fauna and flora) especially in Nigeria. ... Possible e-waste management strategies will also be highlighted on soil ...

Direct anodic hydrochloric acid and cathodic caustic production during water electrolysis

Science.gov (United States)

Lin, Hui-Wen; Cejudo-Marín, Rocío; Jeremiasse, Adriaan W.; Rabaey, Korneel; Yuan, Zhiguo; Pikaar, Ilje

2016-02-01

Hydrochloric acid (HCl) and caustic (NaOH) are among the most widely used chemicals by the water industry. Direct anodic electrochemical HCl production by water electrolysis has not been successful as current commercially available electrodes are prone to chlorine formation. This study presents an innovative technology simultaneously generating HCl and NaOH from NaCl using a Mn0.84Mo0.16O2.23 oxygen evolution electrode during water electrolysis. The results showed that protons could be anodically generated at a high Coulombic efficiency (i.e. ≥ 95%) with chlorine formation accounting for 3 ~ 5% of the charge supplied. HCl was anodically produced at moderate strengths at a CE of 65 ± 4% together with a CE of 89 ± 1% for cathodic caustic production. The reduction in CE for HCl generation was caused by proton cross-over from the anode to the middle compartment. Overall, this study showed the potential of simultaneous HCl and NaOH generation from NaCl and represents a major step forward for the water industry towards on-site production of HCl and NaOH. In this study, artificial brine was used as a source of sodium and chloride ions. In theory, artificial brine could be replaced by saline waste streams such as Reverse Osmosis Concentrate (ROC), turning ROC into a valuable resource.

Decontamination of electronic waste-polluted soil by ultrasound-assisted soil washing.

Science.gov (United States)

Chen, Fu; Yang, Baodan; Ma, Jing; Qu, Junfeng; Liu, Gangjun

2016-10-01

Laboratorial scale experiments were performed to evaluate the efficacy of a washing process using the combination of methyl-β-cyclodextrin (MCD) and tea saponin (TS) for simultaneous desorption of hydrophobic organic contaminants (HOCs) and heavy metals from an electronic waste (e-waste) site. Ultrasonically aided mixing of the field contaminated soil with a combination of MCD and TS solutions simultaneously mobilizes most of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and the analyte metal (Pb, Cu, and Ni) burdens. It is found that 15 g/L MCD and 10 g/L TS is an efficient reagent combination reconciling extraction performance and reagent costs. Under these conditions, the removal efficiencies of HOCs and heavy metals are 93.5 and 91.2 %, respectively, after 2 cycles of 60-min ultrasound-assisted washing cycles. By contrast, 86.3 % of HOCs and 88.4 % of metals are removed from the soil in the absence of ultrasound after 3 cycles of 120-min washing. The ultrasound-assisted soil washing could generate high removal efficiency and decrease the operating time significantly. Finally, the feasibility of regenerating and reusing the spent washing solution in extracting pollutants from the soil is also demonstrated. By application of this integrated technology, it is possible to recycle the washing solution for a purpose to reduce the consumption of surfactant solutions. Collectively, it has provided an effective and economic treatment of e-waste-polluted soil.

Dark matter axions and caustic rings

International Nuclear Information System (INIS)

Sikivie, P.

1997-01-01

This report contains discussions on the following topics: the strong CP problem; dark matter axions; the cavity detector of galactic halo axions; and caustic rings in the density distribution of cold dark matter halos

Solid waste disposal in the soil: effects on the physical, chemical, and organic properties of soil

Directory of Open Access Journals (Sweden)

Vanessa Regina Lasaro Mangieri

2015-04-01

Full Text Available Currently, there is growing concern over the final destination of the solid waste generated by society. Landfills should not be considered the endpoint for substances contained or generated in solid waste. The sustainable use of natural resources, especially soil and water, has become relevant, given the increase in anthropogenic activities. Agricultural use is an alternative to solid waste (leachate, biosolid disposal, considering the hypothesis that the agricultural use of waste is promising for reducing waste treatment costs, promoting nutrient reuse and improving the physical and chemical conditions of soil. Thus, this literature review, based on previously published data, seeks to confirm or disprove the hypothesis regarding the promising use of solid waste in agriculture to decrease the environmental liability that challenges public administrators in the development of efficient management. The text below addresses the following subtopics after the introduction: current solid waste disposal and environmental issues, the use of solid waste in agriculture, and the effect on the physical and chemical properties of soil and on organic matter, ending with final considerations.

Cu retention in an acid soil amended with perlite winery waste

DEFF Research Database (Denmark)

Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Gómez-Armesto, Antía

2016-01-01

The effect of perlite waste from a winery on general soil characteristics and Cu adsorption was assessed. The studied soil was amended with different perlite waste concentrations corresponding to 10, 20, 40 and 80 Mg ha(-1). General soil characteristics and Cu adsorption and desorption curves were...

Bioremediation of uranium contaminated soils and wastes

International Nuclear Information System (INIS)

Francis, A.J.

1998-01-01

Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (1) stabilization of uranium and toxic metals with reduction in waste volume and (2) removal and recovery of uranium and toxic metals from wastes and contaminated soils. Stabilization of uranium and toxic metals in wastes is accomplished by exploiting the unique metabolic capabilities of the anaerobic bacterium, Clostridium sp. The radionuclides and toxic metals are solubilized by the bacteria directly by enzymatic reductive dissolution, or indirectly due to the production of organic acid metabolites. The radionuclides and toxic metals released into solution are immobilized by enzymatic reductive precipitation, biosorption and redistribution with stable mineral phases in the waste. Non-hazardous bulk components of the waste volume. In the second process uranium and toxic metals are removed from wastes or contaminated soils by extracting with the complexing agent citric acid. The citric-acid extract is subjected to biodegradation to recover the toxic metals, followed by photochemical degradation of the uranium citrate complex which is recalcitrant to biodegradation. The toxic metals and uranium are recovered in separate fractions for recycling or for disposal. The use of combined chemical and microbiological treatment process is more efficient than present methods and should result in considerable savings in clean-up and disposal costs

Retention of low-level radioacrive waste material by soil

International Nuclear Information System (INIS)

Essington, E.H.; Fowler, E.B.; Polzer, W.L.

1979-01-01

Beacuse of the wide variations in soil and waste characteristics, the degree of radionuclide retention would be expected to vary; knowledge of that variation may be of value in predicting radionuclde mobility. This report discusses results of investigations of radioactive waste/soil interactions as they relate to radionucldie retention and its variability among soils and radionuclides. In soil column leaching studies, radioactive waste solutions were applied to four different soil types; 241 Am, 88 Y, and 172 Hf were retained in the top four cm of soil with better than 90% retained by a protective surface sand layer. Less than 50% of the 85 Sr, 137 Cs, and 83 Rb was retained by the surface sand. No 88 Y, 172 Hf, 85 Sr, 137 Cs, or 83 Rb was detected by gamma counting in the leachate solutions, however, using a more sensitive analytical technique small amounts of 238 Pu, 239 240 Pu and 241 Am were found in leachates from all soils. It appears that release of this small fraction of mobile radionuclide may have a significant long-term impact on the environment. It aslo appears that reliance for attenuation of some radionuclides can not be placed solely on characteristics of the soil matrix

Changes in hydrocarbon groups, soil ecotoxicity and microbiology along horizontal and vertical contamination gradients in an old landfarming field for oil refinery waste

International Nuclear Information System (INIS)

Mikkonen, Anu; Hakala, Kati P.; Lappi, Kaisa; Kondo, Elina; Vaalama, Anu; Suominen, Leena

2012-01-01

Horizontal and vertical contaminant gradients in an old landfarming field for oil refinery waste were characterised with the aim to assess parallel changes in hydrocarbon groups and general, microbiological and ecotoxicological soil characteristics. In the surface soil polar compounds were the most prevalent fraction of heptane-extractable hydrocarbons, superseding GC–FID-resolvable and high-molar-mass aliphatics and aromatics, but there was no indication of their relatively higher mobility or toxicity. The size of the polar fraction correlated poorly with soil physical, chemical and microbiological properties, which were better explained by the total heptane-extractable and total petroleum hydrocarbons (TPH). Deleterious effects on soil microbiology in situ were observed at surprisingly low TPH concentrations (0.3%). Due to the accumulation of polar and complexed degradation products, TPH seems an insufficient measure to assess the quality and monitor the remediation of soil with weathered hydrocarbon contamination. - Highlights: ► Weathered hydrocarbon contamination and soil quality on landfarm site were studied. ► Silica fractionation of hydrocarbons separated aliphatics, aromatics and polars. ► Polar hydrocarbon metabolites had accumulated in the surface soil. ► Total hydrocarbons and TPH correlated with soil quality changes better than polars. ► Toxic response of soil microbial biomass and activity were seen at low TPH (<0.5%). - Polar metabolites constitute the largest fraction of crude oil-derived contaminants in a landfarming site, but TPH better explains soil microbial and ecotoxicological responses.

Petrographic, mineralogical and geochemical characterization of the Serrinha coal waste pile (Douro Coalfield, Portugal) and the potential environmental impacts on soil, sediments and surface waters

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, J. [Centro de Geologia, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Ferreira da Silva, E. [GeoBioTec, Geobiosciences, Geotechnologies and Geoengineering Research Center, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro (Portugal); Li, Z.; Ward, C. [School of Biological, Earth and Environmental Sciences, University of New South Wales. Sydney, NSW 2052 (Australia); Flores, D. [Departamento de Geociencias, Ambiente e Ordenamento do Territorio, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal)

2010-09-01

Serrinha is the largest coal waste pile resulting from mining activities in the Douro Coalfield, Portugal. The exploitation of anthracite in tens of small mines caused some environmental impacts, as is the case of the coal waste piles that exist in old mines and adjacent areas. The Serrinha waste pile is essentially made up of 2 million tonnes of shales and carbonaceous shales, deposited in a topographical depression over about 30 years. Despite the environmental restoration accomplished in the Serrinha waste pile, some environmental problems seem to persist. In this study a petrographic, mineralogical and geochemical characterization was done in order to recognize and understand these problems. The materials studied were coal waste, sediments and waters from the drainage system and decanting basins, soils from the surrounding areas, leachates from waste material and neoformed minerals formed at the bottom of the waste pile. The main lithologies (carbonaceous shale and lithic arenite) and coal from the Douro Coalfield were also analyzed. Petrographic analysis shows some evidence of weathering (on organic and inorganic matter) related to the time of exposure to the weathering agents and the easy access of air within the waste pile (due to both the poor compaction and the heterogeneity of the material). Mineralogically, the composition of coal waste material has contributions from both the coal and the associated lithologies. R-type cluster analysis of the waste pile material allows two distinct clusters to be identified. In the first cluster a sulfide fraction is represented by the association of As, Cd, Cu, Pb, Ni and Zn, while Fe clustered with Al, Co, and Ti indicates that some of the Fe and the other elements are likely associated with silicate minerals such as clays. The second cluster, represented by Cr, V, Zr, Rb, REE, Mn, Li and Ba, probably represent a silicate fraction, perhaps detrital accessory minerals. The waste pile material, leachates, soils

Structured caustic vector vortex optical field: manipulating optical angular momentum flux and polarization rotation.

Science.gov (United States)

Chen, Rui-Pin; Chen, Zhaozhong; Chew, Khian-Hooi; Li, Pei-Gang; Yu, Zhongliang; Ding, Jianping; He, Sailing

2015-05-29

A caustic vector vortex optical field is experimentally generated and demonstrated by a caustic-based approach. The desired caustic with arbitrary acceleration trajectories, as well as the structured states of polarization (SoP) and vortex orders located in different positions in the field cross-section, is generated by imposing the corresponding spatial phase function in a vector vortex optical field. Our study reveals that different spin and orbital angular momentum flux distributions (including opposite directions) in different positions in the cross-section of a caustic vector vortex optical field can be dynamically managed during propagation by intentionally choosing the initial polarization and vortex topological charges, as a result of the modulation of the caustic phase. We find that the SoP in the field cross-section rotates during propagation due to the existence of the vortex. The unique structured feature of the caustic vector vortex optical field opens the possibility of multi-manipulation of optical angular momentum fluxes and SoP, leading to more complex manipulation of the optical field scenarios. Thus this approach further expands the functionality of an optical system.

Toxicity Assessment of Contaminated Soils of Solid Domestic Waste Landfill

Science.gov (United States)

Pasko, O. A.; Mochalova, T. N.

2014-08-01

The paper delivers the analysis of an 18-year dynamic pattern of land pollutants concentration in the soils of a solid domestic waste landfill. It also presents the composition of the contaminated soils from different areas of the waste landfill during its operating period. The authors calculate the concentrations of the following pollutants: chrome, nickel, tin, vanadium, lead, cuprum, zinc, cobalt, beryllium, barium, yttrium, cadmium, arsenic, germanium, nitrate ions and petrochemicals and determine a consistent pattern of their spatial distribution within the waste landfill area as well as the dynamic pattern of their concentration. Test-objects are used in experiments to make an integral assessment of the polluted soil's impact on living organisms. It was discovered that the soil samples of an animal burial site are characterized by acute toxicity while the area of open waste dumping is the most dangerous in terms of a number of pollutants. This contradiction can be attributed to the synergetic effect of the polluted soil, which accounts for the regularities described by other researchers.

A Software for soil quality conservation at organic waste disposal areas: The case of olive mill and pistachio wastes.

Science.gov (United States)

Doula, Maria; Sarris, Apostolos; Papadopoulos, Nikos; Hliaoutakis, Aggelos; Kydonakis, Aris; Argyriou, Lemonia; Theocharopoulos, Sid; Kolovos, Chronis

2016-04-01

For the sustainable reuse of organic wastes at agricultural areas, apart from extensive evaluation of waste properties and characteristics, it is of significant importance, in order to protect soil quality, to evaluate land suitability and estimate the correct application doses prior waste landspreading. In the light of this precondition, a software was developed that integrates GIS maps of land suitability for waste reuse (wastewater and solid waste) and an algorithm for waste doses estimation in relation to soil analysis, and in case of reuse for fertilization with soil analysis, irrigation water quality and plant needs. EU and legislation frameworks of European Member States are also considered for the assessment of waste suitability for landspreading and for the estimation of the correct doses that will not cause adverse effects on soil and also to underground water (e.g. Nitrate Directive). Two examples of software functionality are presented in this study using data collected during two LIFE projects, i.e. Prosodol for landspreading of olive mill wastes and AgroStrat for pistachio wastes.

A middle age addicted man with caustic stomach

Directory of Open Access Journals (Sweden)

Gholamreza Nouri Broujerdi

2014-06-01

Full Text Available Background: The term caustic generally refers to alkaline and the term corrosive generally refers to acidic agents' injury; however, in medical literature caustic is frequently a term applied to both substances. Ingested alkali typically damage the esophagus more than stomach or duodenum, whereas acids usually cause more severe gastric injury. Since esophagus has a slightly alkaline pH, its epithelium is more resistant to acids, so that only 6 to 20% of those who ingest these substances present lesions in this organ. Case : A middle-aged addicted man who drunk hydrochloric acid accidentally had extensive necrosis of the stomach with remarkable sparing of the esophagus on second look exploration. A total gastrectomy with a Roux-en-Y esophago-jejunostomy with feeding jejunostomy was performed. Conclusion : In caustic GI injury, patients who are operated on and found to have no evidence of extensive esophago-gastric necrosis, a biopsy of the posterior gastric wall should be performed to exclude occult injury. If histologically there is a question of viability, a second look operation should be performed within 36 hours.

Caustic addition system operability test procedure

International Nuclear Information System (INIS)

Parazin, R.E.

1994-11-01

This test procedure provides instructions for performing operational testing of the major components of the 241-AN-107 Caustic Addition System by WHC and Kaiser personnel at the Rotating Equipment Shop run-in pit (Bldg. 272E)

Caustic addition system operability test procedure

Energy Technology Data Exchange (ETDEWEB)

Parazin, R.E.

1994-11-01

This test procedure provides instructions for performing operational testing of the major components of the 241-AN-107 Caustic Addition System by WHC and Kaiser personnel at the Rotating Equipment Shop run-in pit (Bldg. 272E).

Forming artificial soils from waste materials for mine site rehabilitation

Science.gov (United States)

Yellishetty, Mohan; Wong, Vanessa; Taylor, Michael; Li, Johnson

2014-05-01

Surface mining activities often produce large volumes of solid wastes which invariably requires the removal of significant quantities of waste rock (overburden). As mines expand, larger volumes of waste rock need to be moved which also require extensive areas for their safe disposal and containment. The erosion of these dumps may result in landform instability, which in turn may result in exposure of contaminants such as trace metals, elevated sediment delivery in adjacent waterways, and the subsequent degradation of downstream water quality. The management of solid waste materials from industrial operations is also a key component for a sustainable economy. For example, in addition to overburden, coal mines produce large amounts of waste in the form of fly ash while sewage treatment plants require disposal of large amounts of compost. Similarly, paper mills produce large volumes of alkaline rejected wood chip waste which is usually disposed of in landfill. These materials, therefore, presents a challenge in their use, and re-use in the rehabilitation of mine sites and provides a number of opportunities for innovative waste disposal. The combination of solid wastes sourced from mines, which are frequently nutrient poor and acidic, with nutrient-rich composted material produced from sewage treatment and alkaline wood chip waste has the potential to lead to a soil suitable for mine rehabilitation and successful seed germination and plant growth. This paper presents findings from two pilot projects which investigated the potential of artificial soils to support plant growth for mine site rehabilitation. We found that pH increased in all the artificial soil mixtures and were able to support plant establishment. Plant growth was greatest in those soils with the greatest proportion of compost due to the higher nutrient content. These pot trials suggest that the use of different waste streams to form an artificial soil can potentially be used in mine site rehabilitation

Earthworms as bio-indicators of chemical pollution in soils with drilling waste

Directory of Open Access Journals (Sweden)

Kujawska Justyna

2017-01-01

Full Text Available The deposited drilling waste may alter the functioning of soil ecosystems by disrupting the soil fauna. The wastes contain toxic compounds such as metals or hydrocarbons, which tend to accumulate in the living. In the research, earthworms were used u as bio-indicators of soil pollution resulting from the presence of pollution contained in drilling waste. The aim of this study is to evaluation of toxicity of the waste of spent oil and water drilling cuttings to earthworm Eisenia fetida. Oil-based and water-based drilling cuttings were added to soil, used six doses of drilling wastes (5%, 10%, 15%, 25%, 30%, 50%. The results showed that the 45 days LC50 of oil-based drilling cuttings ranged 18%, LC50 of water-based drilling cuttings ranged 33%. In general, mortality increases with increasing dosage waste.

Caustic ingestion injuries-at military hospital rawalpindi

International Nuclear Information System (INIS)

Ahsan, O.; Razzaq, K.; Abbas, W.; Zarrin, F.

2015-01-01

To study the pattern and endoscopic severity of caustic ingestion injuries presenting at Military Hospital Rawalpindi. Study Design: Descriptive study. Place and Duration of Study: The study was conducted at Medical and Gastroenterology Department Military Hospital Rawalpindi from August 2012 to April 2013. Material and Methods: Patients were selected from those who presented with caustic ingestion history in Medical OPD, ER and in medical wards. After informed consent the patient underwent upper gastrointestinal (GI) Endoscopy. Endoscopic findings were recorded. Results: Out of 50 patients, 21(42%) were males and 29 (58%) were females. Ingestion was accidental in 19 (38%) and was with intent of suicide or self-harm in 31(62%) patients. Mean age was 33.2 years (SD ± 13.2). All the patients were subjected to upper GI endoscopy and findings were recorded. Endoscopic findings were grade 0 in 4 (8%), Grade 1 in 6 (12%), grade 2a in 7 (14%), grade 2b in 10 (20%), grade 3a in 6 (12%) and grade 3b in 17 (34%) patients. Conclusion: Caustic ingestion injuries were seen more in younger females with predominant cause as suicidal intent. On endoscopic examination severe corrosive injuries were more frequent. (author)

Soil workability as a basis for advice on tillage activities

NARCIS (Netherlands)

Cadena Zapata, M.

1999-01-01

In the tropical area of Mexico, when and how to carry out tillage is a qualitative decision. There is no quantified information about the interaction between a chosen process of cultivation, soil type and weather, which dictate the tool and power requirements. Waste of energy and soil

Soil contamination adjacent to waste tank 8

International Nuclear Information System (INIS)

Odum, J.V.

1976-11-01

In March and April 1961, miscalibrated liquid level instrumentation resulted in an overfilling of tank 8 to about 5 in. above the fill-line entrance. The resultant liquid head caused waste to seep through an asbestos-packed sleeve to the fill-line encasement and from there into the main encasement. Most of this waste returned to primary containment (i.e., the catch tank) through a separately encased drain line. However, approximately 1500 gal of high heat waste leaked from the fill-line encasement into the ground, probably through the joint at the juncture of the fill-line encasement and the concrete encasement of the waste tank. The contamination is contained in a 1000- to 1500-ft 3 zone of soil 12 to 26 ft below grade, 18 ft above the maximum elevation of the water table, and distributed roughly symmetrically around the fill-line encasement. Estimates from a continuing monitoring program indicate that less than 5000 Ci of 137 Cs, less than 0.005 Ci of 238 239 Pu, and less than 0.5 Ci of 89 90 Sr are in the soil. Analysis indicates that the contamination presents no current or future hazard to the environment; consequently, there is no technical reason for excavation of this soil. The high cost of excavation and exposure of personnel make excavation undesirable. The contaminated soil will remain under surveillance and undisturbed at tank 8 until the tank is removed from service, at which time its disposition will be re-evaluated

Ingestion of Caustic Substances in Adults: A Review Article

Directory of Open Access Journals (Sweden)

Andon Chibishev

2013-02-01

Full Text Available Background: Ingestion of caustic agents can cause serious damages of the upper gastrointestinal tract and in some cases this kind of poisoning may have fatal outcomes. Acute caustic intoxications are one of the main problems in the modern clinical toxicology since they mainly affect young people with psychic disorders, suicidal intent, and alcohol addiction. Text: In diagnostic evaluation of this kind of poisoning, different procedures are used. Today’s golden standard for determination of the grade and extent of the lesion is esophagogastroduodenoscopy (EGD performed in the first 12-24 hours following corrosive ingestion. In some patients, some late complications, such as esophageal stenosis and gastric stenosis, which are the most common, as well as carcinoma of the upper gastrointestinal tract, which is rarely seen, can be detected. Acute caustic poisonings are treated with specific kinds of protocols. According to them, first, an attempt is made to neutralize the poison. Combinations of antibiotics, anti-secretory drugs, and collagen synthesis inhibitors are used. As a support therapy, nutritional liquids can be utilized, and in the most unmanageable cases, esophageal dilatation, stent placement and surgery are used. Conclusion: In the future, caustic poisonings will remain a serious socio-medical issue, due to the difficult clinical presentation, expensive diagnostic protocol, extended hospitalization, and possible permanent disability.

Treatment of Radioactive Contaminated Soil and Concrete Wastes Using the Regulatory Clearance

Energy Technology Data Exchange (ETDEWEB)

Kang, Il Sik; Ryu, W. S.; Kim, T. K.; Shon, J. S.; Ahn, S. J.; Lee, Y. H.; Bae, S. M.; Hong, D. S.; Ji, Y. Y.; Lee, B. C

2008-11-15

In the radioactive waste storage facilities at the Korea Atomic Energy Research Institute (KAERI) in Daejoen, there are thousands drums of radioactive contaminated soil and concrete wastes. The soil and concrete wastes were generated in 1988 during the decommissioning process of the research reactor and the attached radioactive waste treatment facility which were located in Seoul. The wastes were transported to Daejeon and have been stored since then. At the generation time, the radioactive contamination of the wastes was very low, and the radionuclides in the wastes was Co-60 and Cs-137. As the wastes have been stored for more than 20 years, the radioactivity concentration of the wastes has been decayed to become very extremely low. The wastes are needed to be treated because they take up large spaces at the storage facility. Also by treating the wastes, final disposal cost can be saved. So, the regulatory clearance was considered as a treatment method for the soil and concrete wastes with extremely low radioactivity concentration.

Wavefield extrapolation in caustic-free normal ray coordinates

KAUST Repository

Ma, Xuxin

2012-11-04

Normal ray coordinates are conventionally constructed from ray tracing, which inherently requires smooth velocity profiles. To use rays as coordinates, the velocities have to be smoothed further to avoid caustics, which is detrimental to the mapping process. Solving the eikonal equation numerically for a line source at the surface provides a platform to map normal rays in complex unsmoothed velocity models and avoid caustics. We implement reverse-time migration (RTM) and downward continuation in the new ray coordinate system, which allows us to obtain efficient images and avoid some of the dip limitations of downward continuation.

Carbon and nitrogen mineralization in vineyard acid soils amended with a bentonitic winery waste

Science.gov (United States)

Fernández-Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Díaz-Raviña, Montserrat; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel

2015-04-01

Carbon mineralization and nitrogen ammonification processes were determined in different vineyard soils. The measurements were performed in samples non-amended and amended with different bentonitic winery waste concentrations. Carbon mineralization was measured as CO2 released by the soil under laboratory conditions, whereas NH4+ was determined after its extraction with KCl 2M. The time evolution of both, carbon mineralization and nitrogen ammonification, was followed during 42 days. The released CO2 was low in the analyzed vineyard soils, and hence the metabolic activity in these soils was low. The addition of the bentonitic winery waste to the studied soils increased highly the carbon mineralization (2-5 fold), showing that the organic matter added together the bentonitic waste to the soil have low stability. In both cases, amended and non-amended samples, the maximum carbon mineralization was measured during the first days (2-4 days), decreasing as the incubation time increased. The NH4+ results showed an important effect of bentonitic winery waste on the ammonification behavior in the studied soils. In the non-amended samples the ammonification was no detected in none of the soils, whereas in the amended soils important NH4+ concentrations were detected. In these cases, the ammonification was fast, reaching the maximum values of NH4 between 7 and 14 days after the bentonitic waste additions. Also, the percentages of ammonification respect to the total nitrogen in the soil were high, showing that the nitrogen provided by the bentonitic waste to the soil is non-stable. The fast carbon mineralization found in the soils amended with bentonitic winery wastes shows low possibilities of the use of this waste for the increasing the organic carbon pools in the soil.On the other hand, the use of this waste as N-fertilizer can be possible. However, due its fast ammonification, the waste should be added to the soils during active plant growth periods.

Industrial Wastes as Auxiliary Additives to Cement/Lime Stabilization of Soils

Directory of Open Access Journals (Sweden)

Jijo James

2016-01-01

Full Text Available Chemical stabilization involves the use of chemical agents for initiating reactions within the soil for modification of its geotechnical properties. Cement and lime stabilization have been the most common stabilization methods adopted for soil treatment. Cement stabilization results in good compressive strengths and is preferred for cohesionless to moderately cohesive soil but loses effectiveness when the soil is highly plastic. Lime stabilization is the most preferred method for plastic clays; however, it proves to be ineffective in sulphate rich clays and performs poorly under extreme conditions. With such drawbacks, lots of researches have been undertaken to address the issues faced with each stabilization method, in particular, the use of solid wastes for soil stabilization. Solid waste reuse has gained high momentum for achieving sustainable waste management in recent times. Research has shown that the use of solid wastes as additives with and replacement for conventional stabilizers has resulted in better results than the performance of either individually. This review provides insight into some of the works done by earlier researchers on lime/cement stabilization with industrial wastes as additives and helps to form a sound platform for further research on industrial wastes as additives to conventional stabilizers.

Hydrogen peroxide and caustic soda: Dancing with a dragon while bleaching

Science.gov (United States)

Peter W. Hart; Carl Houtman; Kolby Hirth

2013-01-01

When hydrogen peroxide is mixed with caustic soda, an auto-accelerating reaction can lead to generation of significant amounts of heat and oxygen. On the basis of experiments using typical pulp mill process concentration and temperatures, a relatively simple kinetic model has been developed. Evaluation of these model results reveals that hydrogen peroxide-caustic soda...

Comparative study of engineering properties of two-lime waste tire particle soil and soil with lime/loess ratio of 3:7

Science.gov (United States)

Tiecheng, Yan; Xingyuan, Zhang; Hongping, Yang

2018-03-01

This study describes an analytical comparison of the engineering characteristics of two-lime waste tire particle soil and soil with lime/loess ratio of 3:7 using density measurements, results of indoor consolidation tests, and direct shear tests to examine the strength and deformation characteristics. It investigates the engineering performance of collapsible loess treated with waste tire particles and lime. The results indicate that (1) the shear strength of the two-lime waste tire particle soils increases continuously with soil age; and (2) the two-lime waste tire particle soils are light-weight, strong, and low-deformation soils, and can be applied primarily to improve the foundation soil conditions in areas with collapsible loess soils. This could address the problem of used tire disposal, while providing a new method to consider and manage collapsible loess soils.

Soil Chemical Weathering and Nutrient Budgets along an Earthworm Invasion Chronosequence in a Northern Minnesota Forest

Science.gov (United States)

Resner, K. E.; Yoo, K.; Sebestyen, S. D.; Aufdenkampe, A. K.; Lyttle, A.; Weinman, B. A.; Blum, A.; Hale, C. M.

2011-12-01

We are investigating the impact of exotic earthworms on the rate of nutrient and ion release from soil chemical weathering along an ~200 m invasion chronosequence in a northern Minnesota sugar maple forest. The earthworms belong to three ecological groups that represent different feeding and burrowing behaviors, all of which were introduced from Europe to the previously earthworm-free Great Lakes Region through fishing and agricultural activities. As earthworms digest and mix the soil, we hypothesize that they significantly alter chemical weathering processes by incorporating mineral surfaces to new geochemical environments in their intestines and at different soil depths. The effect of mixing on soil morphology is dramatic, but biogeochemical changes remain largely unknown and therefore are poorly coupled to the current and potential changes in forest ecosystems under the threat of exotic earthworms. We analyze the activities of short-lived isotopes 137-Cs and 210-Pb along with the inorganic chemistry of soil, water, and leaf litter across an invasion transect and link these measurements to the biomass and species composition of exotic earthworms. Earthworms vertically relocate minerals and organic matter largely within the top ~10 cm, which is reflected in the depth profiles of the short-lived isotopes. Among the inorganic nutrients analyzed, Ca is of particular interest due to sugar maple's aptitude for recycling Ca. Fractional mass loss values (tau) of Ca, relative to the soil's parent material, show an enrichment factor of 14 in the least invaded A horizon soils. However, such a high enrichment factor declines dramatically in the heavily invaded soils, suggesting that earthworm activities contribute to leaching Ca. In contrast, the enrichment factor of Fe increases with greater degrees of earthworm invasion, which is consistent with the extraction chemistry data showing greater quantities of pedogenic crystalline iron oxides and greater mineral specific

Initializing numerical weather prediction models with satellite-derived surface soil moisture: Data assimilation experiments with ECMWF's Integrated Forecast System and the TMI soil moisture data set

Science.gov (United States)

Drusch, M.

2007-02-01

Satellite-derived surface soil moisture data sets are readily available and have been used successfully in hydrological applications. In many operational numerical weather prediction systems the initial soil moisture conditions are analyzed from the modeled background and 2 m temperature and relative humidity. This approach has proven its efficiency to improve surface latent and sensible heat fluxes and consequently the forecast on large geographical domains. However, since soil moisture is not always related to screen level variables, model errors and uncertainties in the forcing data can accumulate in root zone soil moisture. Remotely sensed surface soil moisture is directly linked to the model's uppermost soil layer and therefore is a stronger constraint for the soil moisture analysis. For this study, three data assimilation experiments with the Integrated Forecast System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF) have been performed for the 2-month period of June and July 2002: a control run based on the operational soil moisture analysis, an open loop run with freely evolving soil moisture, and an experimental run incorporating TMI (TRMM Microwave Imager) derived soil moisture over the southern United States. In this experimental run the satellite-derived soil moisture product is introduced through a nudging scheme using 6-hourly increments. Apart from the soil moisture analysis, the system setup reflects the operational forecast configuration including the atmospheric 4D-Var analysis. Soil moisture analyzed in the nudging experiment is the most accurate estimate when compared against in situ observations from the Oklahoma Mesonet. The corresponding forecast for 2 m temperature and relative humidity is almost as accurate as in the control experiment. Furthermore, it is shown that the soil moisture analysis influences local weather parameters including the planetary boundary layer height and cloud coverage.

Controls on Weathering of Pyrrhotite in a Low-Sulfide, Granitic Mine-Waste Rock in the Canadian Arctic

Science.gov (United States)

Langman, J. B.; Holland, S.; Sinclair, S.; Blowes, D.

2013-12-01

Increased environmental risk is incurred with expansion of mineral extraction in the Arctic. A greater understanding of geochemical processes associated with hard-rock mining in this cold climate is needed to evaluate and mitigate these risks. A laboratory and in-situ experiment was conducted to examine mineral weathering and the generation of acid rock drainage in a low-sulfide, run-of-mine waste rock in an Arctic climate. Rock with different concentrations of sulfides (primarily pyrrhotite [Fe7S8] containing small amounts of Co and Ni) and carbonates were weathered in the laboratory and in-situ, large-scale test piles to examine leachate composition and mineral weathering. The relatively larger sulfide-containing rock produced sufficient acid to overcome carbonate buffering and produced a declining pH environment with concomitant release of SO4, Fe, Co, and Ni. Following carbonate consumption, aluminosilicate buffering stabilized the pH above 4 until a reduction in acid generation. Results from the laboratory experiment assisted in determining that after consumption of 1.6 percent of the total sulfide, the larger sulfide-concentration test pile likely is at an internal steady-state or maximal weathering rate after seven years of precipitation input and weathering that is controlled by an annual freeze-thaw cycle. Further weathering of the test pile should be driven by external factors of temperature and precipitation in this Arctic, semi-arid region instead of internal factors of wetting and non-equilibrium buffering. It is predicted that maximal weathering will continue until at least 20 percent of the total sulfide is consumed. Using the identified evolution of sulfide consumption in this Arctic climate, a variable rate factor can now be assessed for the possible early evolution and maximal weathering of larger scale waste-rock piles and seasonal differences because of changes in the volume of a waste-rock pile undergoing active weathering due to the freeze

Epidemiology and prevention of caustic ingestion in children

DEFF Research Database (Denmark)

Christesen, H B

1994-01-01

A total of 102 children less than 16 years of age admitted for caustic ingestion in the period 1976-1991 were registered. The annual incidence rate of hospitalization was 10.8:100,000 for the city of Aarhus, Denmark. Esophageal burns occurred with a frequency of 5.0:100,000 per year. Ninety-four ...... of toddlers is recommended. Information material should stress that caustics should always be inaccessible to children and stored separately, and should never be decanted.......A total of 102 children less than 16 years of age admitted for caustic ingestion in the period 1976-1991 were registered. The annual incidence rate of hospitalization was 10.8:100,000 for the city of Aarhus, Denmark. Esophageal burns occurred with a frequency of 5.0:100,000 per year. Ninety......-four percent of the children were less than 5 years old. For this age group, the incidence rates of admission and esophageal burns were 34.6:100,000 and 15.8:100,000, respectively. All ingestions were accidental. The incidence rates of esophageal burns in children 0-4 years old (p = 0.019) decreased...

studies on municipal solid wastes dumping on soil anions, cations

African Journals Online (AJOL)

Osondu

and selected soil enzymes activities of Njoku solid waste dumpsite Owerri municipal, Nigeria were investigated. ... wastes) and sometimes commercial wastes collected by a ... Ethiopian Journal of Environmental Studies and Management Vol.

Study Added of Waste Chicken Egg Shell in Soils

Directory of Open Access Journals (Sweden)

Keng Wong Irwan Lie

2016-01-01

Full Text Available Soil is the foundation of structure or construction that will receive the load transfer through to foundation. If the soil has a carrying capacity of small and cannot withstand the load transfer can result in the failure of construction. If the soil has a carrying capacity of small ground it is necessary to stabilize or improve the soil so that an increase in the carrying capacity of the land so that it can be used for construction. One material is commonly used for soil stabilization with the addition of lime. Waste chicken egg shell is waste that is still rarely used, the results of research [1], states that composition egg shell broadly consists of water (1,6% and dry material (98,4%. The total dry ingredients are there, in shell eggs contained mineral elements (95,1% and protein (3,3%. Based on the existing mineral composition, then the egg shells are composed of crystalline CaCO3 (98,43%, MgCO3 (0,84% and Ca3(PO42 (0,75%. This research was done by adding powdered chicken egg shell waste in clay with a composition of 5%, 7,5%, 10% and 14% with physical properties test and soil compaction test.

Naturally Occurring Radionuclides and Rare Earth Elements Pattern in Weathered Japanese Soil Samples

International Nuclear Information System (INIS)

Sahoo, S.K.; Hosoda, M.; Takahashi, H.; Sorimachi, A.; Ishikawa, T.; Tokonami, S.; Uchida, S.

2011-01-01

From the viewpoint of radiation protection, determination of natural radionuclides e.g. thorium and uranium in soil samples are important. Accurate methods for determination of Th and U is gaining importance. The geochemical behavior of Th, U and rare earth elements (REEs) are relatively close to one another while compared to other elements in geological environment. Radioactive elements like 232 Th and 238 U along with their decay products (e.g. 226 Ra) are present in most of the environmental matrices and can be transferred to living bodies by different pathways that can lead to sources of exposure of man. Therefore, it is necessary to monitor these natural radionuclides in weathered soil samples to assess the possible hazards. The activity concentrations of 226 Ra, 228 Th, and 40 K in soils have been measured using a g γ-ray spectroscopy system with high purity germanium detector. The thorium, uranium and REEs were determined from the same sample using inductively coupled plasma mass spectrometry (ICP-MS). Granitic rocks contain higher amounts of Th, U and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils, as soils are complex heterogeneous mixture of organic and inorganic solids, water and gases. In this paper, we have discussed about distribution pattern of 226 Ra, 232 Th and 238 U along with REEs in soil samples of weathered acid rock (granite and ryolite) collected from two prefectures in Japan: 1. Gifu and 2. Okinawa. (author)

Behaviour of elements in soils developed from nephelinites at Mount Etinde (Cameroon): Impact of hydrothermal versus weathering processes

Science.gov (United States)

Etame, J.; Gerard, M.; Bilong, P.; Suh, C. E.

2009-05-01

The progressive weathering of 0.65 Ma nephelinites from Mount Etinde (South Western Cameroon) in a humid tropical setting has resulted in the formation of a 150 cm thick weathering crust. The soil profiles consist of three horizons: Ah/Bw/C. A major differentiation of the chemical and mineralogical parameters is related to the complexity of the saprolites, some of which were hydrothermally altered. Bulk geochemical and microgeochemical analyses were performed on selected minerals from the different horizons of two reference profiles, of which one (E 4) was developed from unaltered nephelinite (nephelinite U) while the other (BO 1) formed from hydrothermally altered nephelinite (nephelinite H). The results show that the primary minerals (clinopyroxene, nepheline, leucite, haüyne, titanomagnetite, perovskite, apatite and sphene) experienced differential weathering rates with primary minerals rich in rare earth elements (titanomagnetite, perovskite, apatite and sphene) surviving in the saprolite and the Bw horizons. The weathering of the primary minerals is reflected in the leaching of alkaline and alkaline-earth elements, except for Ba and Rb in the hydrothermalised nephelinite soil. The order of mobility is influenced by hydrothermal processes: Na > K > Rb > Ca > Cs > Sr in nephelinite U soil , Na > K > Sr > Ca > Mg in nephelinite H soil; Rb/Sr and Sr/Mg can be used as indicators of the kinetic of the weathering on nephelinite U and on nephelinite H. Barium enrichment is related to variable concentrations in the nephelinites, to the formation of crandallites and the leaching of surface horizons. The content of metallic elements is higher in nephelinite H soil than in the nephelinite U soil. Results show that hydrothermal alteration leads to an enrichment of light (La, Ce, Nd) and intermediate (Sm, Eu, Dy) rare earth elements. The enrichment in Cr and Pb in the surface horizons is discussed in relation to organic matter activity, the dissolution of magnetites, and

Waste reduction by separation of contaminated soils during environmental restoration

International Nuclear Information System (INIS)

Roybal, J.A.; Conway, R.; Galloway, B.; Vinsant, E.; Slavin, P.; Guerin, D.

1998-06-01

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill

Influence of industrial solid waste addition on properties of soil-cement bricks

OpenAIRE

Siqueira, F. B.; Amaral, M. C.; Bou-Issa, R. A.; Holanda, J. N. F.

2016-01-01

Abstract The reuse of pollutant solid wastes produced in distinct industrial activities (avian eggshell waste and welding flux slag waste) as a source of alternative raw material for producing soil-cement bricks for civil construction was investigated. Soil-cement bricks containing up to 30 wt% of industrial solid waste were uniaxially pressed and cured for 28 days. Special emphasis is given on the influence of solid waste addition on the technical properties (as such volumetric shrinkage, wa...

ISOCELL trademark proof-of-concept for retrieval of wastes and contaminated soil

International Nuclear Information System (INIS)

Chatwin, T.D.; Krieg, R.K.

1992-01-01

ISOCELL TM cryogenic technology is designed to immobilize buried hazardous, radioactive, and mixed waste and contaminated soil by creating a block of frozen waste and soil that can be safely retrieved, stored, transported, and treated with a minimum of dust or aerosol production. A ''proof-of-concept'' test of the ISOCELL process was conducted in clean soil by RKK, Ltd., for the Idaho National Engineering Laboratory (INEL). Results indicate ISOCELL technology successfully froze moist soil into a solid block capable of being lifted and retrieved. Test conditions were compared to characteristics of possible buried waste sites in the INEL

Secondary Waste Considerations for Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center FY-2001 Status Report

International Nuclear Information System (INIS)

Herbst, A.K.; Kirkham, R.J.; Losinski, S.J.

2002-01-01

The Idaho Nuclear Technology and Engineering Center (INTEC) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes from the melter off-gas clean up systems. Projected secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates

Secondary Waste Considerations for Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Technology and Engineering Center FY-2001 Status Report

Energy Technology Data Exchange (ETDEWEB)

Herbst, A.K.; Kirkham, R.J.; Losinski, S.J.

2002-09-26

The Idaho Nuclear Technology and Engineering Center (INTEC) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes from the melter off-gas clean up systems. Projected secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

Secondary Waste Considerations for Vitrification of Sodium-Bearing Waste at the Idaho Nuclear Techology and Engineering Center FY-2001 Status Report

Energy Technology Data Exchange (ETDEWEB)

Herbst, Alan Keith; Kirkham, Robert John; Losinski, Sylvester John

2001-09-01

The Idaho Nuclear Technology and Engineering Center (INTEC) is considering vitrification to process liquid sodium-bearing waste. Preliminary studies were completed to evaluate the potential secondary wastes from the melter off-gas clean up systems. Projected secondary wastes comprise acidic and caustic scrubber solutions, HEPA filters, activated carbon, and ion exchange media. Possible treatment methods, waste forms, and disposal sites are evaluated from radiological and mercury contamination estimates.

Studying the microlenses mass function from statistical analysis of the caustic concentration

Energy Technology Data Exchange (ETDEWEB)

Mediavilla, T; Ariza, O [Departamento de Estadistica e Investigacion Operativa, Universidad de Cadiz, Avda de Ramon Puyol, s/n 11202 Algeciras (Spain); Mediavilla, E [Instituto de Astrofisica de Canarias, Avda Via Lactea s/n, La Laguna (Spain); Munoz, J A, E-mail: teresa.mediavilla@ca.uca.es, E-mail: octavio.ariza@uca.es, E-mail: emg@iac.es [Departamento de Astrofisica y Astronomia, Universidad de Valencia, Burjassot, Valencia (Spain)

2011-09-22

The statistical distribution of caustic crossings by the images of a lensed quasar depends on the properties of the distribution of microlenses in the lens galaxy. We use a procedure based in Inverse Polygon Mapping to easily identify the critical and caustic curves generated by a distribution of stars in the lens galaxy. We analyze the statistical distributions of the number of caustic crossings by a pixel size source for several projected mass densities and different mass distributions. We compare the results of simulations with theoretical binomial distributions. Finally we apply this method to the study of the stellar mass distribution in the lens galaxy of QSO 2237+0305.

16 CFR 1500.129 - Substances named in the Federal Caustic Poison Act.

Science.gov (United States)

2010-01-01

... Poison Act. 1500.129 Section 1500.129 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL... REGULATIONS § 1500.129 Substances named in the Federal Caustic Poison Act. The Commission finds that for those substances covered by the Federal Caustic Poison Act (44 Stat. 1406), the requirements of section 2(p)(1) of...

Toxicity Determinations for Five Energetic Materials, Weathered and Aged in Soil, to the Collembolan Folsomia Candida

Science.gov (United States)

2015-03-01

obtained from the Soil Fauna and Ecotoxicology Research Unit, Department of Terrestrial Ecology, National Environmental Research Institute (Silkeborg...AND AGED IN SOIL , TO THE COLLEMBOLAN FOLSOMIA CANDIDA ECBC-TR-1273 Carlton T. Phillips Ronald T. Checkai Roman G. Kuperman Michael Simini...for Five Energetic Materials, Weathered and Aged in Soil , to the Collembolan Folsomia candida 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

Humic Substances in Organic Wastes and their Effects on Amended Soils

Science.gov (United States)

Senesi, N.; Ciavatta, C.; Plaza, C.

2009-04-01

Soil humic substances (HS) are universally recognized to play a major role in a wide number of agronomic and environmental processes. For example, soil HS are able to bind mineral particles together, thus promoting a good soil structure, constitute an important source of nutrients for plants and microorganisms, contribute largely to the acid-base buffering capacity of soils, and exert a marked control on the biological availability, physico-chemical behavior, and environmental fate of toxic metal ions and xenobiotics. For these reasons, the knowledge of the short- and long-term effects of organic amendments on the status, quality, and reactivity of indigenous soil HS is of paramount importance. The objective of this presentation is to provide an overview of the chemical and physico-chemical data available in the literature for the evaluation of the effects of organic wastes of various origin and nature used as soil amendments on the composition, structure, and chemical reactivity of native soil HS. In general, HS-like components of organic wastes are typically characterized by a relatively larger presence of aliphatic, amide, and polysaccharide structures, simple structural components of wide molecular heterogeneity, smaller contents of oxygen, acidic functional groups, and organic free radicals, and smaller degrees of aromatic ring polycondensation, polymerization, and humification than native soil HS. Further, with respect to native soil HS, HS-like fractions from organic wastes generally exhibit smaller binding capacities and affinities for metal ions and organic xenobiotics. Appropriate treatment processes of raw organic wastes able to produce environmentally safe and agronomically efficient soil amendments, such as composting, yield HS-like fractions characterized by chemical and physico-chemical features that approach those of native soil HS. In general, aliphatic, polysaccharide, and lignin structures and S- and N-containing groups of the HS-like fractions

Use of Sr isotopes as a tool to decipher the soil weathering processes in a tropical river catchment, southwestern India

International Nuclear Information System (INIS)

Gurumurthy, G.P.; Balakrishna, K.; Tripti, M.; Riotte, Jean; Audry, Stéphane; Braun, Jean-Jacques; Udaya Shankar, H.N.

2015-01-01

River water composition (major ion and "8"7Sr/"8"6Sr ratio) was monitored on a monthly basis over a period of three years from a mountainous river (Nethravati River) of southwestern India. The total dissolved solid (TDS) concentration is relatively low (46 mg L"−"1) with silica being the dominant contributor. The basin is characterised by lower dissolved Sr concentration (avg. 150 nmol L"−"1), with radiogenic "8"7Sr/"8"6Sr isotopic ratios (avg. 0.72041 at outlet). The composition of Sr and "8"7Sr/"8"6Sr and their correlation with silicate derived cations in the river basin reveal that their dominant source is from the radiogenic silicate rock minerals. Their composition in the stream is controlled by a combination of physical and chemical weathering occurring in the basin. The molar ratio of SiO_2/Ca and "8"7Sr/"8"6Sr isotopic ratio show strong seasonal variation in the river water, i.e., low SiO_2/Ca ratio with radiogenic isotopes during non-monsoon and higher SiO_2/Ca with less radiogenic isotopes during monsoon season. Whereas, the seasonal variation of Rb/Sr ratio in the stream water is not significant suggesting that change in the mineral phase being involved in the weathering reaction could be unlikely for the observed molar SiO_2/Ca and "8"7Sr/"8"6Sr isotope variation in river water. Therefore, the shift in the stream water chemical composition could be attributed to contribution of ground water which is in contact with the bedrock (weathering front) during non-monsoon and weathering of secondary soil minerals in the regolith layer during monsoon. The secondary soil mineral weathering leads to limited silicate cation and enhanced silica fluxes in the Nethravati river basin. - Highlights: • Systematic monthly geochemical monitoring of a mountainous tropical river. • Soil weathering has dominant control on the surface water chemistry in the basin. • Soil redox process plays a dominant role in leaching of soil minerals. • Soil mineral weathering in

Study of incorporation of casting wastes in soil-cement blocks

International Nuclear Information System (INIS)

Folmann, R.; Malkowski, W.; Valentina, L.V.D.; Folgureras, M.V.

2011-01-01

Soil-cement bricks are an ecological alternative to conventional ones because they don't need to be burned to gain strength. This study examines the technical possibility of reuse of foundry sand as fine aggregate in soil-cement. The raw materials were characterized by X-ray diffraction, thermal analysis and particle size. The foundry sand wastes were mixed at different levels to soil and cement. Compaction tests were performed to define the mixtures at optimum moisture content corresponding to the maximum density. Isothermal Conduction Calorimeter was performed to study the influence of waste in the cement hydration reaction. The results indicate that the addition of foundry sand waste decreases the optimum moisture content and increases the maximum density without significantly affecting the cement set. (author)

Analyses of soils at commercial radioactive waste disposal sites

International Nuclear Information System (INIS)

Piciulo, P.L.; Shea, C.E.; Barletta, R.E.

1983-01-01

Brookhaven National Laboratory, in order to provide technical assistance to the NRC, has measured a number of physical and chemical characteristics of soils from three commercial low-level radioactive waste disposal sites. Samples were collected from an area adjacent to the disposal site at Sheffield, IL, and from two operating sites: one at Barnwell, SC, and the other near Richland, WA. The soil samples, which were analyzed from each site, were believed to include soil which was representative of that in contact with buried waste forms. Results of field measurements of earth resistivity and of soil pH will be presented. Additionally, the results of laboratory measurements of resistivity, moisture content, pH, exchange acidity and the soluble ion content of the soils will be discussed. The soluble ion content of the soils was determined by analysis of aqueous extracts of saturated soil pastes. The concentrations of the following ions were determined: Ca 2+ , Mg 2+ , K + , Na + , HCO 3 - , CO 3 2- , SO 4 2- , Cl - , S 2-

Caustic meso-optical confocal microscope for vertical particle tracks. Proposal

International Nuclear Information System (INIS)

Soroko, L.M.

1995-01-01

The principal of the proposed caustic meso-optical microscope for vertical particle tracks in the nuclear photoemulsion is explained. The results of the experiments performed to illustrate the main features of this new meso-optical microscope are given. The proposed caustic meso-optical microscope for vertical particle tracks in the nuclear photoemulsion can be effectively used in the experimental investigation of such rare processes as ν μ - ν τ oscillations and of the Pb-Pb interactions. 2 refs., 7 figs

Pilot tests of microbe-soil combined treatment of waste drilling sludge

OpenAIRE

Lirong Chen; Min Huang; Xuebin Jiang; Hui Li; Qiang Chen; Min Zhang; Shenglin Li

2015-01-01

Microbe-soil combined treatment is a newly developed technology in view of the defects of the curing process and waste drilling mud slag properties. In particular, 0.3%–0.5% bioremediation reagents were fully mixed with the waste drilling sludge according to its wet and dry degree, and 1.5 folds to twice weight of more finely ground soil was added in the mix, which was covered by soil of 5–15 cm thick and thereby grasses or greeneries were planted on the soil. The process was successfully app...

Repeated soil application of organic waste amendments reduces draught force and fuel consumption for soil tillage

DEFF Research Database (Denmark)

Peltrea, Clément; Nyord, Tavs; Bruun, Sander

2015-01-01

Abstract Soil application of organic waste products (OWP) can maintain or increase soil organic carbon (SOC) content, which in turn could lead to increased porosity and potentially to reduced energy use for soil tillage. Only a few studies have addressed the effect of SOC content on draught force...... for soil tillage, and this still needs to be addressed for fields that receive diverse types of organic waste of urban, agricultural and agro-industrial origin. The objective of this study was to determine the effect of changes in SOC induced by repeated soil application of OWP on draught force for soil...... tillage and tractor fuel consumption. Draught force was measured for tillage with conventional spring tillage tines, as well as bulk density, soil texture and SOC content in the CRUCIAL field experiment, Denmark in which diverse types of OWP had been applied annually for 11 years. The OWP included...

Managing soil moisture on waste burial sites

International Nuclear Information System (INIS)

Anderson, J.E.; Ratzlaff, T.D.

1991-11-01

Shallow land burial is a common method of disposing of industrial, municipal, and low-level radioactive waste. The exclusion of water from buried wastes is a primary objective in designing and managing waste disposal sites. If wastes are not adequately isolated, water from precipitation may move through the landfill cover and into the wastes. The presence of water in the waste zone may promote the growth of plant roots to that depth and result in the transport of toxic materials to above-ground foliage. Furthermore, percolation of water through the waste zone may transport contaminants into ground water. This report presents results from a field study designed to assess the the potential for using vegetation to deplete soil moisture and prevent water from reaching buried wastes at the Idaho National Engineering Laboratory (INEL). Our results show that this approach may provide an economical means of limiting the intrusion of water on waste sites

Possibility of forming artificial soil based on drilling waste and sewage sludge

Science.gov (United States)

Kujawska, J.; Pawłowska, M.; Wasag, H.

2018-05-01

Land redevelopment is necessary due to the amount of a degraded area. Depositing waste on the small area of landfills is harmful for the environment. New methods of managing and utilizing waste are being sought in order to minimize the deposition of waste. In small amounts, many types of waste can be treated as a substrate or material improving physicochemical properties of soils, and hence can be used in reclamation of degraded lands. The study analysed the effect of different doses of sewage sludge (35%, 17.5%) with addition (2.5% and 5%) of drilling waste on the properties of degraded soils. The results show that created mixtures improve the sorption properties of soil. The mixtures contain the optimal the ratio of nutrient elements for growth of plants is N:P:K.

Long-term evolution of radio-active waste storage in geological formations: analogy with the weathering of mineral deposits

International Nuclear Information System (INIS)

Cantinolle, P.; Griffault, L.; Jebrak, M.

1986-01-01

The aim of this study was to select examples of mineral deposits and their weathering environment, showing the long-term behaviour, in geological time, measuring (area, volume) some constituent elements of radio-active waste storage subject to the hazards of hydrogeochemical weathering. Initially, a feasibility study was made to collate data available within the BRGM (mining group and public service) and from literature dealing with weathering of deposits. It was thus discovered that the analogy between radio-active waste storage and mineral deposits could be approached in two different yet complementary ways: - one approach is to observe the behaviour of a mineral deposit in relation to the country rocks. For this a bibliographic metallogenic study was made. The other approach is to observe the behaviour of chemical elements during deposition of a mineral deposit whose genesis is similar to the spatial and thermal environment of a deposit of radio-active waste in a geological formation. For this two sites were selected corresponding to hydrothermal systems showing strong analogies to those expected in the neighbourhood of the storage sites. These two sites, Langenberg in the Vosges and La Telhaie in Brittany, were the subject of complementary analytical work [fr

Changes in Soil Chemical Properties and Lettuce Yield Response Following Incorporation of Biochar and Cow Dung to Highly Weathered Acidic Soils

DEFF Research Database (Denmark)

Agyei Frimpong, Kwame; Amoakwah, Emmanuel; Osei, Benjamin A

2016-01-01

imposed on two highly weathered, acidic soils from the coastal savanna and tropical rainforest agroecological zones of Ghana, respectively, to elucidate their effect on yield of lettuce. The study showed that application of biochar solely or in combination with cow dung increased soil pH, total organic...... carbon, and cation exchange capacity, and temporarily increased soil respiration and microbial biomass carbon. Further, incorporation of combined application of cow dung and biochar increased lettuce yield more than sole incorporation of either amendment. The study demonstrated that corn cob biochar can...... improve soil chemical properties and lettuce yield if applied solely or in combination with cow dung....

Robustness of discrete flows and caustics in cold dark matter cosmology

International Nuclear Information System (INIS)

Natarajan, Aravind; Sikivie, Pierre

2005-01-01

Although a simple argument implies that the distribution of dark matter in galactic halos is characterized by discrete flows and caustics, their presence is often ignored in discussions of galactic dynamics and of dark matter detection strategies. Discrete flows and caustics can in fact be irrelevant if the number of flows is very large. We estimate the number of dark matter flows as a function of galactocentric distance and consider the various ways in which that number can be increased, in particular, by the presence of structure on small scales (dark matter clumps) and the scattering of the flows by inhomogeneities in the matter distribution. We find that, when all complicating factors are taken into account, discrete flows and caustics in galactic halos remain a robust prediction of cold dark matter cosmology with extensive implications for observation and experiment

Biodegradable Stents for Caustic Esophageal Strictures: Do They Work?

Science.gov (United States)

Kochhar, Rakesh; Samanta, Jayanta; Basha, Jahangeer; Verma, Abhai; Choudhuri, Gourdas; Lakhtakia, Sundeep; Reddy, D Nageshwar

2017-08-01

Biodegradable (BD) stents have been used for the management of various esophageal strictures (ES) but the experience of its use in caustic strictures is limited. The present study, aimed at evaluating efficacy of BD stents for the treatment of refractory caustic-induced ES, was a retrospective multi-center study conducted at three tertiary care centers in India wherein adult patients with refractory caustic induced strictures underwent placement of a BD stent. Patients were followed up for immediate complications and long term outcome. All 13 patients (39.3 ± 15.1 years) underwent successful BD stent placement. Retrosternal chest pain occurred in 2 patients and stent migration in 1 (7.6%) patient. At 3 months, restenosis with recurrence of dysphagia was seen in nine (69.2%) patients, at 6 months, 10 (77%) patients had dysphagia of whom three underwent surgery and the remaining seven patients required dilatations. At 1 year, one patient remained asymptomatic while nine had dysphagia. The requirement for dilatation was once in 3 months in seven patients & once in a month in two patients. At 2 years, the requirement of dilatations was further reduced to once in 4-6 months in all patients. Over a 3 year follow up three (23%) patients had undergone surgery, one was free of symptoms while nine patients continued to be on periodic dilatation although the requirement had reduced to once in 4-6 months. Efficacy of BD stents in patients with caustic-induced ES is limited and the short term radial force applied by the currently available BD stents is inadequate to provide long term relief in such patients.

Changes in hydrocarbon groups, soil ecotoxicity and microbiology along horizontal and vertical contamination gradients in an old landfarming field for oil refinery waste.

Science.gov (United States)

Mikkonen, Anu; Hakala, Kati P; Lappi, Kaisa; Kondo, Elina; Vaalama, Anu; Suominen, Leena

2012-03-01

Horizontal and vertical contaminant gradients in an old landfarming field for oil refinery waste were characterised with the aim to assess parallel changes in hydrocarbon groups and general, microbiological and ecotoxicological soil characteristics. In the surface soil polar compounds were the most prevalent fraction of heptane-extractable hydrocarbons, superseding GC-FID-resolvable and high-molar-mass aliphatics and aromatics, but there was no indication of their relatively higher mobility or toxicity. The size of the polar fraction correlated poorly with soil physical, chemical and microbiological properties, which were better explained by the total heptane-extractable and total petroleum hydrocarbons (TPH). Deleterious effects on soil microbiology in situ were observed at surprisingly low TPH concentrations (0.3%). Due to the accumulation of polar and complexed degradation products, TPH seems an insufficient measure to assess the quality and monitor the remediation of soil with weathered hydrocarbon contamination. Copyright © 2011 Elsevier Ltd. All rights reserved.

A review of the Hanford Site soil corrosion applicable to solid waste containers

International Nuclear Information System (INIS)

Divine, J.R.

1991-05-01

The first phase of the assessment of the soil corrosion in the solid waste burial grounds of the 200 Areas at the Hanford Site is completed with this review of both existing information developed at the site and relevant offsite information. Detailed soil corrosion data are needed for several reasons: (1) the possibility of predicting the damage to the containers of the retrievable stored transuranic waste that are under soil cover, (2) the feasibility of forecasting the state of waste containers being retrieved in remedial investigation/feasibility studies, (3) the capability of predicting subsidence of the soil over the waste containers, and (4) the capability of forecasting when stored lead shielding or hazardous chemicals might be exposed to the environment. Because corrosion in soils is dependent on the soil type, site-specific data are required even though offsite data can provide guidance on the type and the approximate extent of corrosion to expect. These data permit rough estimations of the corrosion rates of a variety of materials -- including carbon steels, cast irons, stainless steels, and lead -- in the Hanford Site soils. This report attempts to compile these data to facilitate current estimates of waste container longevity. However, because of the lack of well-documented, site-specific data, it is difficult to provide a definite life expectancy for waste containers and other structures. Consequently, additional data are essential for reliable container life estimates. 36 refs., 10 figs., 7 tabs

Chromium isotope fractionation during oxidative weathering of a modern basaltic weathering profile

DEFF Research Database (Denmark)

D'Arcy, Joan Mary; Døssing, Lasse Nørbye; Frei, Robert

Chromium can be used as a tracer of redox sensitive environmental processes. In soils Cr (III) is inert, immobile and resides predominantly in minerals, clays and oxides. Cr (VI) is toxic, soluble and mobile and is usually lost from the soil to local run off. Chromium isotopes have been shown...... to fractionate under both reducing and oxidizing conditions [1, 2]. Recent studies on d53Cr isotopes in laterite soils show that oxidative weathering of Cr-bearing rocks is accompanied by an isotopic fractionation, where by the lighter isotopes are retained in the residual soil and the heavier isotope...... is enriched in local runoff [1]. This study aims to quantify the stable Cr isotope composition of two modern basaltic weathering profiles, to help better understand the processes that oxidize inert Cr (III) to toxic Cr (VI). We sampled basaltic weathering profiles and associated river waters from areas of two...

The Effect of paper mill waste and sewage sludge amendments on soil organic matter

Science.gov (United States)

Méndez, Ana; Barriga, Sandra; Guerrero, Francisca; Gascó, Gabriel

2013-04-01

In general, Mediterranean soils have low organic matter content, due to the climate characteristics of this region and inadequate land management. Traditionally, organic wastes such as manure are used as amendment in order to improve the soil quality, increasing soil fertility by the accumulation of nitrogen, phosphorus and other plant nutrients in the soil. In the last decade, other anthropogenic organic wastes such as sewage sludge or paper waste materials have been studied as soil amendments to improve physical, chemical and biological properties of soils. The objective of the present work was to study the influence of waste from a paper mill and sewage sludge amendments on soil organic matter. For this reason, soil organic matter evolution was studied using thermogravimetric analysis (TGA), the derivative (dTG) and differential thermal analysis (DTA). Thermal analytical techniques have the advantage of using full samples without pre-treatments and have been extensively used to study the evolution of organic matter in soils, to evaluate composting process or to study the evolution of organic matter of growing media.

Field-scale assessment of phytotreatment of soil contaminated with weathered hydrocarbons and heavy metals

Energy Technology Data Exchange (ETDEWEB)

Palmroth, M.R.T.; Koskinen, P.E.P.; Tuhkanen, T.A.; Puhakka, J.A. [Inst. of Environmental Engineering and Biotechnology, Tampere Univ. of Tech., Tampere (Finland); Pichtel, J. [Natural Resources and Environmental Management, Ball State Univ., Muncie, IN (United States); Vaajasaari, K. [Pirkanmaa Regional Environment Centre, Tampere (Finland); Joutti, A. [Finnish Environment Inst., Helsinki (Finland)

2006-08-15

Background, Aims, and Scope. Phytoremediation is remediation method which uses plants to remove, contain or detoxify environmental contaminants. Phytoremediation has successfully been applied for the removal of fresh hydrocarbon contamination, but removal of aged hydrocarbons has proven more difficult. Biodegradation of hydrocarbons in the subsurface can be enhanced by the presence of plant roots, i.e. the rhizosphere effect. Phytostabilization reduces heavy metal availability via immobilization in the rhizosphere. Soils contaminated by both hydrocarbons and heavy metals are abundant and may be difficult to treat. Heavy metal toxicity can inhibit the activity of hydrocarbon-degrading micro-organisms and decrease the metabolic diversity of soil bacteria. In this experiment, weathered hydrocarbon- and heavy metal-contaminated soil was treated using phytoremediation in a 39-month field study in attempts to achieve both hydrocarbon removal and heavy metal stabilization. Methods. A combination of hydrocarbon degradation and heavy metal stabilization was evaluated in a field-scale phytoremediation study of weathered contaminants. Soil had been contaminated over several years with hydrocarbons (11,400{+-}4,300 mg kg dry soil){sup -1} and heavy metals from bus maintenance activities and was geologically characterized as till. Concentrations of soil copper, lead and zinc were 170{+-}50 mgkg{sup -1}, 1,100{+-}1,500 mg kg{sup -1} and 390{+-} 340 mg kg{sup -1}, respectively. The effect of contaminants, plant species and soil amendment (NPK fertilizer or biowaste compost) on metabolic activity of soil microbiota was determined. Phytostabilization performance was investigated by analyses of metal concentrations in plants, soil and site leachate as well as acute toxicity to Vibrio fischeri and Enchtraeus albidus. Results. Over 39 months hydrocarbon concentrations did not decrease significantly (P=0.05) in non-amended soil, although 30% of initial hydrocarbon concentrations were

Reducing the leachability of nitrate, phosphorus and heavy metals from soil using waste material

Directory of Open Access Journals (Sweden)

Faridullah

Full Text Available Abstract Contaminants like nitrate (NO3, phosphorus (P and heavy metals in water are often associated with agricultural activities. Various soil and water remediation techniques have been employed to reduce the risk associated with these contaminants. A study was conducted to examine the extent of leaching of heavy metals (Cd, Ni, Pb and Cr, NO3 and P. For this purpose sandy and silt loam soils were amended with different waste materials, namely wood ash, solid waste ash, vegetable waste, charcoal, and sawdust. The soils were saturated with wastewater. Irrespective of the waste applied, the pH and EC of the amended soils were found to be greater than the control. Charcoal, sawdust and wood ash significantly decreased heavy metals, nitrate and phosphorus concentrations in the leachate. Treatments were more efficient for reducing Ni than other heavy metals concentrations. Waste amendments differed for heavy metals during the process of leaching. Heavy metals in the soil were progressively depleted due to the successive leaching stages. This research suggests that waste material may act as an adsorbent for the above contaminants and can reduce their leachability in soils.

Characteristics of soils and saprolite in Solid Waste Storage Area 6

International Nuclear Information System (INIS)

Ammons, J.T.; Phillips, D.H.; Timpson, M.E.

1987-01-01

Solid Waste Storage Area 6 (SWSA-6) is one of the disposal sites for solid low-level radioactive waste at Oak Ridge National Laboratory. Soils and saprolites from the site were characterized to provide base line information to initiate assessment for remedial actions and closure plans. Physical, chemical, mineralogical, and engineering analyses were conducted on soil and saprolite samples

Physical chemistry characterization of soils of the Storage Center of Radioactive Wastes

International Nuclear Information System (INIS)

Hernandez T, U. O.; Fernandez R, E.; Monroy G, F.; Anguiano A, J.

2011-11-01

Any type of waste should be confined so that it does not causes damage to the human health neither the environment and for the storage of the radioactive wastes these actions are the main priority. In the Storage Center of Radioactive Wastes the radioactive wastes generated in Mexico by non energy applications are storage of temporary way. The present study is focused in determining the physical chemistry properties of the lands of the Storage Center of Radioactive Wastes like they are: real density, ph, conductivity percentage of organic matter and percentage of humidity. With what is sought to make a characterization to verify the reaction capacity of the soils in case of a possible flight of radioactive material. The results show that there are different density variations, ph and conductivity in all the soil samples; the ph and conductivity vary with regard to the contact time between the soil and their saturation point in water, for the case of the density due to the characteristics of the same soil; for what is not possible to establish a general profile, but is necessary to know the properties of each soil type more amply. Contrary case is the content of organic matter and humidity since both are in minor proportions. (Author)

Radionuclide Incorporation in Secondary Crystalline Minerals Resulting from Chemical Weathering of Selected Waste Glasses: Progress Report: Task kd.5b

International Nuclear Information System (INIS)

Mattigod, Shas V.; Serne, R. Jeffrey; Legore, Virginia L.; Parker, Kent E.; Orr, Robert D.; McCready, David E.; )

2003-01-01

Experiments were conducted by Pacific Northwest National Laboratory to evaluate potential incorporation of radionuclides in secondary mineral phases that form from weathering vitrified nuclear waste glasses. These experiments were conducted as part of the Immobilized Low-Activity Waste-Performance Assessment (ILAW-PA) to generate data on radionuclide mobilization and transport in a near-field environment of disposed vitrified wastes. The results of these experiments demonstrated that radionuclide sequestration can be significantly enhanced by promoting the formation of cage structured minerals such as sodalite from weathering glasses. These results have important implications regarding radionuclide sequestration/mobilization aspects that are not currently accounted for in the ILAW PA. Additional studies are required to confirm the results and to develop an improved understanding of the mechanisms of sequestration of radionuclides into the secondary and tertiary weathering products o f the ILAW glass to help refine how contaminants are released from the near-field disposal region out into the accessible environment. Of particular interest is to determine whether the contaminants remain sequestered in the glass weathering products for hundreds to thousands of years. If the sequestration can be shown to continue for long periods, another immobilization process can be added to the PA analysis and predicted risks should be lower than past predictions

Effect of Different Organic Wastes on Soil Propertie s and Plant Growth and Yield: a Review

Directory of Open Access Journals (Sweden)

Hossain M. Z.

2017-12-01

Full Text Available The use of organic wastes in agriculture plays a great role in recycling essential plant nutrients, sustaining soil security as well as protecting the environment from unwanted hazards. This review article deals with the effect of different kinds of organic wastes on soil properties and plant growth and yield. Municipal solid waste is mainly used as a source of nitrogen and organic matter, improving soil properties and microbial activity that are closely related to soil fertility. Biowaste and food waste increase pH, nitrogen content, cation exchange capacity, water holding capacity, and microbial biomass in soil. Sewage sludge contains various amounts of organic matter and huge amounts of plant nutrients. Manure is a common waste which improves soil properties by adding nutrients and increases microbial and enzyme activity in soil. It also reduces toxicity of some heavy metals. These organic wastes have a great positive impact on soil physical, chemical, and biological properties as well as stimulate plant growth and thus increase the yield of crops.

Response of soil microorganisms to radioactive oil waste: results from a leaching experiment

Science.gov (United States)

Galitskaya, P.; Biktasheva, L.; Saveliev, A.; Ratering, S.; Schnell, S.; Selivanovskaya, S.

2015-06-01

Oil wastes produced in large amounts in the processes of oil extraction, refining, and transportation are of great environmental concern because of their mutagenicity, toxicity, high fire hazardousness, and hydrophobicity. About 40% of these wastes contain radionuclides; however, the effects of oil products and radionuclides on soil microorganisms are frequently studied separately. The effects on various microbial parameters of raw waste containing 575 g of total petroleum hydrocarbons (TPH) kg-1 waste, 4.4 of 226Ra, 2.8 of 232Th, and 1.3 kBq kg-1 of 40K and its treated variant (1.6 g kg-1 of TPH, 7.9 of 226Ra, 3.9 of 232Th, and 183 kBq kg-1 of 40K) were examined in a leaching column experiment to separate the effects of hydrocarbons from those of radioactive elements. The raw waste sample (H) was collected from tanks during cleaning and maintenance, and a treated waste sample (R) was obtained from equipment for oil waste treatment. Thermal steam treatment is used in the production yard to reduce the oil content. The disposal of H waste samples on the soil surface led to an increase in the TPH content in soil: it became 3.5, 2.8, and 2.2 times higher in the upper (0-20 cm), middle (20-40 cm), and lower (40-60cm) layers, respectively. Activity concentrations of 226Ra and 232Th increased in soil sampled from both H- and R- columns in comparison to their concentrations in control soil. The activity concentrations of these two elements in samples taken from the upper and middle layers were much higher for the R-column compared to the H-column, despite the fact that the amount of waste added to the columns was equalized with respect to the activity concentrations of radionuclides. The H waste containing both TPH and radionuclides affected the functioning of the soil microbial community, and the effect was more pronounced in the upper layer of the column. Metabolic quotient and cellulase activity were the most sensitive microbial parameters as their levels were changed 5

Barrier capacity of weathered coal mining wastes with respect to heavy metal and organic contaminants

International Nuclear Information System (INIS)

Twardowska, I.; Jarosinska, B.

1992-01-01

Some types of weathered, buffered coal mining wastes (CMW), being essentially heterogenous and complex mineralogical system of developed surface area, under certain conditions could be widely applicable for binding a variety of contaminants both inorganic in cationic or anionic form, and organic compounds. The experiments reported earlier, showed excellent Cr(VI)-binding capacity of CMW. In this paper, experiments on simultaneous removal of heavy metals Cr t , Cu 2+ , Zn 2+ and Cd 2+ from highly (pH 2.5) and mildly acidic solutions (pH 4.0), as well as of organic compounds and color reduction in leachate from solid industrial waste dump (foundry wastes) will be presented

Monitoring caustic injuries from emergency department databases using automatic keyword recognition software.

Science.gov (United States)

Vignally, P; Fondi, G; Taggi, F; Pitidis, A

2011-03-31

In Italy the European Union Injury Database reports the involvement of chemical products in 0.9% of home and leisure accidents. The Emergency Department registry on domestic accidents in Italy and the Poison Control Centres record that 90% of cases of exposure to toxic substances occur in the home. It is not rare for the effects of chemical agents to be observed in hospitals, with a high potential risk of damage - the rate of this cause of hospital admission is double the domestic injury average. The aim of this study was to monitor the effects of injuries caused by caustic agents in Italy using automatic free-text recognition in Emergency Department medical databases. We created a Stata software program to automatically identify caustic or corrosive injury cases using an agent-specific list of keywords. We focused attention on the procedure's sensitivity and specificity. Ten hospitals in six regions of Italy participated in the study. The program identified 112 cases of injury by caustic or corrosive agents. Checking the cases by quality controls (based on manual reading of ED reports), we assessed 99 cases as true positive, i.e. 88.4% of the patients were automatically recognized by the software as being affected by caustic substances (99% CI: 80.6%- 96.2%), that is to say 0.59% (99% CI: 0.45%-0.76%) of the whole sample of home injuries, a value almost three times as high as that expected (p < 0.0001) from European codified information. False positives were 11.6% of the recognized cases (99% CI: 5.1%- 21.5%). Our automatic procedure for caustic agent identification proved to have excellent product recognition capacity with an acceptable level of excess sensitivity. Contrary to our a priori hypothesis, the automatic recognition system provided a level of identification of agents possessing caustic effects that was significantly much greater than was predictable on the basis of the values from current codifications reported in the European Database.

Spatial gradient of chemical weathering and its coupling with physical erosion in the soils of the Betic Cordillera (SE Spain)

Science.gov (United States)

Schoonejans, Jerome; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Kubik, Peter

2015-04-01

The production and denudation of soil material are controlled by chemical weathering and physical erosion which influence one another. Better understanding and quantification of this relationship is critical to understand biogeochemical cycles in the critical zone. The intense silicate weathering that is taking place in young mountain ranges is often cited to be a negative feedback that involves a long-term reduction of the atmospheric CO2 and the temperature cooling. However the possible (de)coupling between weathering and erosion is not fully understood for the moment and could reduce the effect of the feedback. This study is conducted in the eastern Betic Cordillera located in southeast Spain. The Betic Cordillera is composed by several mountains ranges or so-called Sierras that are oriented E-W to SE-NW and rise to 2000m.a.s.l. The Sierras differ in topographic setting, tectonic activity, and slightly in climate and vegetation. The mountain ranges located in the northwest, such as the Sierra Estancias, have the lowest uplift rates ( ~20-30 mm/kyr); while those in the southeast, such as the Sierra Cabrera, have the highest uplift rates ( >150mm/kyr). The sampling was realised into four small catchments located in three different Sierras. In each of them, two to three soil profiles were excavated on exposed ridgetops, and samples were taken by depth slices. The long-term denudation rate at the sites is inferred from in-situ 10Be CRN measurements. The chemical weathering intensity is constrained using a mass balance approach that is based on the concentration of immobile elements throughout the soil profile (CDF). Our results show that the soil depth decreases with an increase of the denudation rates. Chemical weathering accounts for 5 to 35% of the total mass lost due to denudation. Higher chemical weathering intensities (CDFs) are observed in sites with lower denudation rates (and vice versa). The data suggest that chemical weathering intensities are strongly

Environmental risk assessment of the use of different organic wastes as soil amendments

Science.gov (United States)

Alvarenga, Paula; Palma, Patrícia; Mourinha, Clarisse; Farto, Márcia; Cunha-Queda, Ana Cristina; Natal-da-Luz, Tiago; Sousa, José Paulo

2013-04-01

The use of organic wastes in agriculture is considered a way of maintaining or restoring the quality of soils, enlarging the slow cycling soil organic carbon pool. However, a wide variety of undesired substances, such as potentially trace elements and organic contaminants, can have adverse effects on the environment. That fact was highlighted by the Proposal for a Soil Framework Directive, which recognized that "soil degradation or soil improvements have a major impact on other areas, (…) such as surface waters and groundwater, human health, climate change, protection of nature and biodiversity, and food safety". Taking that into account, the research project "ResOrgRisk" aims to assess the environmental risk involved in the use of different organic wastes as soil amendments, evidencing their benefits and constraints, and defining the most suitable tests to reach such assessment. The organic wastes selected for this purpose were: sewage sludge, limed, not limed, and co-composted with agricultural wastes, agro-industrial sludge, mixed municipal solid waste compost, compost produced from organic farming residues, and pig slurry digestate. Whereas threshold values for heavy metals in sludge used for agriculture have been set by the European Commission, actually there is no definitive European legislation for organic contaminants. Guide values for some organic contaminants (e.g. polychlorinated biphenyls - PCBs, and polycyclic aromatic hydrocarbons - PAHs) have been adopted at national level by many European countries, such as Portugal. These values should be taken into account when assessing the risk involved in the use of organic wastes as soil amendments. However, chemical analysis of organic waste often gives scarce information because it does not include possible interactions between chemicals. Furthermore, an exhaustive identification and quantification of all substances is impractical. In this study, ecotoxicological tests (comprising solid and aquatic phases

Geological and geotechnical characteristics of Metro Manila volcanic soils and their suitability for landfill soil liner

Science.gov (United States)

Mendoza, Edna Patricia; Catane, Sandra; Pascua, Chelo; Zarco, Mark Albert

2010-05-01

Due to the Philippines's island-arc setting, andesitic tuff and volcanic ash constitute two-thirds of the country's agricultural land. In situ weathering of these volcanic sediments produces volcanic soils. Metro Manila volcanic soils were studied to determine their suitability for landfill soil liner. The soils were analyzed using XRD and XRF, and were tested for geotechnical properties. The results show the presence of the smectite group, a swelling variety of clay. The smectite-type clays are weathering products of volcanic glasses which are dominant components of the parental rocks. The high amounts of Al2O3 indicate an Al-rich type of soil. The clay species is either di- or tri-octahedral type, which points to montmorillonite as the main clay species. Swelling clay lowers the permeability of soils and reduces the infiltration and lateral movement of leachates in the ground. Also, geotechnical tests revealed moderate to high plasticity indices and low hydraulic conductivity values. The study shows that the physicochemical characteristics of volcanic soils meet the criteria for a soil liner for future sanitary landfill projects as mandated by RA 9003, a recently ratified solid waste management act of the Philippines. Being widespread, volcanic soils can be viewed as an important resource of the country.

Mineralogic sources of metals in leachates from the weathering of sedex, massive sulfide, and vein deposit mining wastes

Science.gov (United States)

Diehl, S.F.; Hageman, P.L.; Seal, R.R.; Piatak, N.M.; Lowers, H.

2011-01-01

Weathered mine waste consists of oxidized primary minerals and chemically unstable secondary phases that can be sources of readily soluble metals and acid rock drainage. Elevated concentrations of metals such as Cd, Cu, Fe, Mn, Ni, Pb, and Zn are observed in deionized water-based leachate solutions derived from complex sedex and Cu-Pb-Zn mine wastes. Leachate (USGS FLT) from the Elizabeth mine, a massive sulfide deposit, has a pH of 3.4 and high concentrations of Al (16700 ug/L), Cu (440 ug/L), and Zn (8620 ug/L). Leachate from the sedex Faro mine has a pH of 3.5 and high concentrations of Al (2040 ug/L), Cu (1930 ug/L), Pb (2080 ug/L), and Zn (52900 ug/L). In contrast, higher-pH leachates produced from tailings of polymetallic vein deposits have order of magnitude lower metal concentrations. These data indicate that highly soluble secondary mineral phases exist at the surface of waste material where the samples were collected. Sulfide minerals from all sites exhibit differential degrees of weathering, from dissolution etched grain rims, to rinds of secondary minerals, to skeletal remnants. These microscale mineral-dissolution textures enhance weathering and metal teachability of waste material. Besides the formation of secondary minerals, sulfide grains from dried tailings samples may be coated by amorphous Fe-Al-Si minerals that also adsorb metals such as Cu, Ni, and Zn.

Biological treatment of refinery spent caustics under halo-alkaline conditions.

Science.gov (United States)

de Graaff, Marco; Bijmans, Martijn F M; Abbas, Ben; Euverink, Gert-J W; Muyzer, Gerard; Janssen, Albert J H

2011-08-01

The present research demonstrates the biological treatment of refinery sulfidic spent caustics in a continuously fed system under halo-alkaline conditions (i.e. pH 9.5; Na(+)= 0.8M). Experiments were performed in identical gas-lift bioreactors operated under aerobic conditions (80-90% saturation) at 35°C. Sulfide loading rates up to 27 mmol L(-1)day(-1) were successfully applied at a HRT of 3.5 days. Sulfide was completely converted into sulfate by the haloalkaliphilic sulfide-oxidizing bacteria belonging to the genus Thioalkalivibrio. Influent benzene concentrations ranged from 100 to 600 μM. At steady state, benzene was removed by 93% due to high stripping efficiencies and biodegradation. Microbial community analysis revealed the presence of haloalkaliphilic heterotrophic bacteria belonging to the genera Marinobacter, Halomonas and Idiomarina which might have been involved in the observed benzene removal. The work shows the potential of halo-alkaliphilic bacteria in mitigating environmental problems caused by alkaline waste. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of industrial, municipal and agricultural wastes on peanut in lateritic sandy loam soil

International Nuclear Information System (INIS)

Sarkar, S.; Khan, A.R.

2002-06-01

Modern agriculture, worldwide, depends upon the external application of plant nutrients supplied mostly through chemical fertilizer to meet the crop needs. The natural recycling cannot provide the very large amount of nutrients needed year after year in an intensive cropping system and nutrients being a major constraint harvesting the nutrient energy from biological and industrial waste are of prime importance for maximizing the food grain production in the world. A number of industrial wastes like fly ash from thermal power plants, paper factory sludge from paper factory, sewage sludge from municipal source and farmyard manure from livestock farming are the important waste resources, having potentiality in recycling in agricultural land. When these wastes are recycled through soil for crop production, due to the degradative and assimilative capacity of soil, the pollution hazards of these wastes can be minimized to a greater extent as compared to direct disposing of at the site. Fly ash is a waste product residue resulting from the combustion of pulverised coal in coal-fired power generating station. Physico - chemical analysis of fly ash has revealed the presence of both macro-micro nutrients, which can sustain plant growth. Its application in the agricultural land acts as a liming material and improves crop growth by neutralizing the soil acidity, increasing the water availability for the plants and supplement of nutrients (Adriano et al, 1980, Molliner and Street, 1982, Schnappinger et al, 1975). Application of paper factory sludge has been reported to increase the organic carbon content in soil and nutrient content like P, K, Ca, Mg and micronutrients (Guerini et al, 1994, Muse and Mitchell, 1995). Sludge application also improves the organic carbon content of the soil and availability of nutrients like Ca, K and Mg besides improvement of physical properties (Pitchel and Hayes, 1990). Much is known regarding crop performance and changes in physical and

Soil structural analysis tools and properties for Hanford site waste tank evaluation

International Nuclear Information System (INIS)

Moore, C.J.; Holtz, R.D.; Wagenblast, G.R.; Weiner, E.D.; Marlow, R.S.

1995-09-01

As Hanford Site contractors address future structural demands on nuclear waste tanks, built as early as 1943, it is necessary to address their current safety margins and ensure safe margins are maintained. Although the current civil engineering practice guidelines for soil modeling are suitable as preliminary design tools, future demands potentially result in loads and modifications to the tanks that are outside the original design basis and current code based structural capabilities. For example, waste removal may include cutting a large hole in a tank. This report addresses both spring modeling of site soils and finite-element modeling of soils. Additionally seismic dynamic modeling of Hanford Site soils is also included. Of new and special interest is Section 2.2 that Professor Robert D. Holtz of the University of Washington wrote on plane strain soil testing versus triaxial testing with Hanford Site application to large buried waste tanks

Soil structural analysis tools and properties for Hanford site waste tank evaluation

Energy Technology Data Exchange (ETDEWEB)

Moore, C.J.; Holtz, R.D.; Wagenblast, G.R.; Weiner, E.D.; Marlow, R.S.

1995-09-01

As Hanford Site contractors address future structural demands on nuclear waste tanks, built as early as 1943, it is necessary to address their current safety margins and ensure safe margins are maintained. Although the current civil engineering practice guidelines for soil modeling are suitable as preliminary design tools, future demands potentially result in loads and modifications to the tanks that are outside the original design basis and current code based structural capabilities. For example, waste removal may include cutting a large hole in a tank. This report addresses both spring modeling of site soils and finite-element modeling of soils. Additionally seismic dynamic modeling of Hanford Site soils is also included. Of new and special interest is Section 2.2 that Professor Robert D. Holtz of the University of Washington wrote on plane strain soil testing versus triaxial testing with Hanford Site application to large buried waste tanks.

Analysis of caustic soda of different manufacturers in pakistan for mercerization of cotton textiles

International Nuclear Information System (INIS)

Zahid, B.; Faisal, S.; Siddique, S.H.

2017-01-01

Pakistan has sufficient production capacity of caustic soda to cater the needs of the local industry. Presently, Pakistan has four major plants with production capacity around 435,000 mega ton per year of caustic soda of various grades. Textile industry of Pakistan is the major consumer of produced high grade caustic soda; as the presence of any impurities especially dissolved salts and metals is unfavorable for wet processing of cotton. This study investigates the performance of three different local brands of caustic soda intended for use in textile wet processing of cotton fabric specifically for mercerization process. The brands were selected based on their purity grades. The selected caustic soda samples were chemically analyzed for the presence of impurities. Twenty seven cotton fabric samples (nine samples of each brand) were prepared by mercerization in slack state. The cotton fabric samples were tested for changes in surface morphology, tensile strength (warp and weft), tear strength, air permeability and K/S (Colour Strength). The results were analyzed using one-way ANOVA (Analysis of Variance) to ascertain the statistical equivalence within and between the tested brands. The results showed no significant differences across the tested brands at a 95% confidence level except for air permeability and K/S in blue shade. (author)

Life Extension Program for the Modular Caustic Side Solvent Extraction Unit at Savannah River Site - 13179

International Nuclear Information System (INIS)

Samadi, Azadeh

2013-01-01

Caustic Side Solvent Extraction (CSSX) is currently used at the U.S. Department of Energy (DOE) Savannah River Site (SRS) for removal of cesium from the high-level salt-wastes stored in underground tanks. Currently, the Actinide Removal Process (ARP) and the CSSX process are deployed in the (ARP)/Modular CSSX Unit (MCU), to process salt waste for permanent disposition. The CSSX technology utilizes a multi-component organic solvent and annular centrifugal contactors to extract cesium from alkaline salt waste. The original plant was permitted for a three year design life; however, given the successful operation of the plant, a life extension program was completed to continue operations. The program included detailed engineering analyses of the life-expectancy of passive and active components, resulting in component replacement and/or maintenance and monitoring program improvements. The program also included a review of the operations and resulted in a series of operational improvements. Since the improvements have been made, an accelerated processing rate has been demonstrated. In addition, plans for instituting a next-generation solvent are in place and will enhance the decontamination factors. (author)

Wavefield extrapolation in caustic-free normal ray coordinates

KAUST Repository

Ma, Xuxin; Alkhalifah, Tariq Ali

2012-01-01

Normal ray coordinates are conventionally constructed from ray tracing, which inherently requires smooth velocity profiles. To use rays as coordinates, the velocities have to be smoothed further to avoid caustics, which is detrimental to the mapping

Kinetically limited weathering at low denudation rates in semiarid climatic conditions

Science.gov (United States)

Schoonejans, Jérôme; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Christl, Marcus

2016-02-01

Biogeochemical cycling within the Critical Zone depends on the interactions between minerals and fluids controlling chemical weathering and physical erosion rates. In this study, we explore the role of water availability in controlling soil chemical weathering in semiarid climatic conditions. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We combine a geochemical mass balance with 10Be cosmogenic nuclides to constrain chemical weathering intensities and long-term denudation rates. As such, this study presents new data on chemical weathering and 10Be-derived denudation for understudied semiarid climate systems. In the Betic Cordillera, chemical weathering intensities are relatively low (~5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Chemical mass losses are inversely related to denudation rates (14-109 mm/kyr) and positively to soil thickness (14-58 cm); these results are consistent with kinetic limitation of chemical weathering rates. A worldwide compilation of chemical weathering data suggests that soil water balance may regulate the coupling between chemical weathering and physical erosion by modulating soil solute fluxes. Therefore, future landscape evolution models that seek to link chemical weathering and physical erosion should include soil water flux as an essential driver of weathering.

Site Specific Waste Management Instruction for the 116-F-4 soil storage unit

International Nuclear Information System (INIS)

Hopkins, G.G.

1996-08-01

This Site Specific Waste Management Instruction provides guidance for management of waste generated during the excavation and remediation of soil and debris from the 116-4 soil storage unit located at the Hanford Site in Richland, Washington. This document outlines the waste management practices that will be performed in the field to implement federal, state, and US Department of Energy requirements

Use of Waste Marble Dust for Stabilization of Clayey Soil

Directory of Open Access Journals (Sweden)

Altug SAYGILI

2015-11-01

Full Text Available The main objective of this research is to investigate the possibility of utilizing waste marble dust in stabilizing problematic soils (especially swelling clays. The research work was divided into two sections. The first section deals with the shear strength parameters and swelling characteristics, the second section deals with the microstructural investigation of the improved problematic soils. The marble dust addition ratios which have been studied were 0 %, 5 %, 10 %, 20 % and 30 % by weight. Physical, mechanical and chemical properties of soil and marble dust samples were investigated. In addition, SEM analyses were performed on the specimens. Test results indicate that marble dust addition improved the shear strength parameters and reduced the swell potential of the tested clay samples. Marble dust had a noticeable role in the hydration process because of high calcium content. Obtained results showed that marble dust addition to the clay samples will reduce the cost of constructing structures on problematic soils, and finding new utilization areas for waste marble dust will decrease environmental pollution. Utilizing waste marble dust materials in problematic soils will have great contribution to the economy and conservation of resources.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.11966

Detecting Anthropogenic Disturbance on Weathering and Erosion Processes

Science.gov (United States)

Vanacker, V.; Schoonejans, J.; Bellin, N.; Ameijeiras-Mariño, Y.; Opfergelt, S.; Christl, M.

2014-12-01

Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical erosion, with direct implications on local biogeochemical cycling. However, the feedback mechanisms between soil erosion, chemical weathering and biogeochemical cycling in response to anthropogenic forcing are not yet fully understood. In this paper, we analyze dynamic soil properties for a rapidly changing anthropogenic landscape in the Spanish Betic Cordillera; and focus on the coupling between physical erosion, soil production and soil chemical weathering. Modern erosion rates were quantified through analysis of sediment deposition volumes behind check dams, and represent catchment-average erosion rates over the last 10 to 50 years. Soil production rates are derived from in-situ produced 10Be nuclide concentrations, and represent long-term flux rates. In each catchment, soil chemical weathering intensities were calculated for two soil-regolith profiles. Although Southeast Spain is commonly reported as the European region that is most affected by land degradation, modern erosion rates are low (140 t ha-1 yr-1). About 50 % of the catchments are losing soils at a rate of less than 60 t km-2 yr-1. Our data show that modern erosion rates are roughly of the same magnitude as the long-term or cosmogenically-derived erosion rates in the Betic Cordillera. Soils developed on weathered metamorphic rocks have no well-developed profile characteristics, and are generally thin and stony. Nevertheless, soil chemical weathering intensities are high; and question the occurrence of past soil truncation.

Geochemical analysis of leachates from cement/low-level radioactive waste/soil systems

International Nuclear Information System (INIS)

Criscenti, L.J.; Serne, R.J.

1988-09-01

Laboratory experiments were conducted as part of the Special Waste Form Lysimeters/endash/Arid Program. These experiments were conducted to investigate the performance of solidified low-level nuclear waste in a typical arid, near-surface disposal site, and to evaluate the ability of laboratory tests to predict leaching in actual field conditions. Batch leaching, soil adsorption column, and soil/waste form column experiments were conducted using Portland III cement waste forms containing boiling-water reactor evaporator concentrate and ion-exchange resin waste. In order to understand the reaction chemistry of the cement waste form/soil/ground-water system, the compositions of the leachates from the laboratory experiments were studied with the aid of the MINTEQ ion speciation/solubility and mass transfer computer code. The purpose of this report is to describe the changes in leachate composition that occur during the course of the experiments, to discuss the geochemical modeling results, and to explore the factors controlling the major element chemistry of these leachates. 18 refs., 84 figs., 14 tabs

Kinetically limited weathering at low denudation rates in semi-arid climates

Science.gov (United States)

Vanacker, V.; Schoonejans, J.; Opfergelt, S.; Ameijeiras-Marino, Y.; Christl, M.

2016-12-01

On Earth, the Critical Zone supports terrestrial life, being the near-surface environment where interactions between the atmosphere, lithosphere, hydrosphere, and biosphere take place Quantitative understanding of the interaction between mechanical rock breakdown, chemical weathering, and physical erosion is essential for unraveling Earth's biogeochemical cycles. In this study, we explore the role of soil water balance on regulating soil chemical weathering under water deficit regimes. Weathering rates and intensities were evaluated for nine soil profiles located on convex ridge crests of three mountain ranges in the Spanish Betic Cordillera. We present and compare quantitative information on soil weathering, chemical depletion and total denudation that were derived based on geochemical mass balance, 10Be cosmogenic nuclides and U-series disequilibria. Soil production rates determined based on U-series isotopes (238U, 234U, 230Th and 226Ra) are of the same order of magnitude as 10Be-derived denudation rates, suggesting steady state soil thickness, in two out of three sampling sites. The chemical weathering intensities are relatively low (˜5 to 30% of the total denudation of the soil) and negatively correlated with the magnitude of the water deficit in soils. Soil weathering extents increase (nonlinearly) with soil thickness and decrease with increasing surface denudation rates, consistent with kinetically limited or controlled weathering. Our study suggests that soil residence time and water availability limit weathering processes in semi-arid climates, which has not been validated previously with field data. An important implication of this finding is that climatic regimes may strongly regulate soil weathering by modulating soil solute fluxes.

Analysis of radioactive waste contamination in soils. Part 1: integral transformations

International Nuclear Information System (INIS)

Romani, Z.V.; Cotta, R.M.; Perez-Guerreo, J.S.; Heilbron Filho, P.F.L.

1997-01-01

The migration of radioactive waste in soils and other porous media is studied through the hybrid numerical-analytical solution of the mass convection-diffusion equations for this phenomenon. Initially, a radionuclide leak function is derived to model the phenomenon that occurs after the failure of the engineering barriers of the repository. This function is obtained from a first order ordinary differential equation which is solved numerically. Subsequently, the migration of this radioactive waste through the soil and the aquifer below the repository is studied; the soil and the aquifer are modeled as two saturated and coupled porous media. The convection-diffusion equations obtained for the concentration field in each medium studied are solved through the use of the Generalized Integral Transform Technique (G.I.T.T.), which provides automatic error control and relatively low computational cost for a user-prescribed accuracy. This work is part of the joint project COPPE/CNEN on the analysis of radioactive waste contamination in soils. (author)

Radon diffusion coefficients for soils. Previous studies and their application to uranium-bearing wastes

International Nuclear Information System (INIS)

Sasaki, Tomozo; Gunji, Yasuyoshi; Iida, Takao

2008-01-01

Radon diffusion in soils has been studied over the years by many researchers. The application of such studies to the evaluation of radiation exposure caused by radon from uranium-bearing wastes disposed in a shallow land site is very important. The present paper surveyed closely relevant studies and elucidated the inherent nature of radon diffusion in terms of the definition of radon diffusion coefficients. Then, basic features of measurement methods for determining radon diffusion coefficients in soils were explained. Furthermore, theoretical aspects of radon diffusion in soils were discussed in terms of microscopic radon diffusion in soils and large-scale radon diffusion through cover soil defects for uranium mill tailings. Finally, in order to apply the radon diffusion studies to uranium-bearing waste disposal in shallow land sites, new challenges were presented: elucidation of radon diffusion in uranium-bearing wastes and cover-soil cracks, and demonstration of the validity of applying only radon diffusion in the evaluation of radiation exposure caused by radon, which would come through Japanese cover soils for uranium-bearing waste disposal. (author)

40 CFR Appendix V to Part 264 - Examples of Potentially Incompatible Waste

Science.gov (United States)

2010-07-01

... corrosive alkalies Lime wastewater Lime and water Spent caustic Group 1-B Acid sludge Acid and water Battery...Cl3 Other water-reactive waste Potential consequences: Fire, explosion, or heat generation; generation... Waste V Appendix V to Part 264 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED...

Application of eggshell waste for the immobilization of cadmium and lead in a contaminated soil.

Science.gov (United States)

Ok, Yong Sik; Lee, Sang Soo; Jeon, Weon-Tai; Oh, Sang-Eun; Usman, Adel R A; Moon, Deok Hyun

2011-01-01

Liming materials have been used to immobilize heavy metals in contaminated soils. However, no studies have evaluated the use of eggshell waste as a source of calcium carbonate (CaCO₃) to immobilize both cadmium (Cd) and lead (Pb) in soils. This study was conducted to evaluate the effectiveness of eggshell waste on the immobilization of Cd and Pb and to determine the metal availability following various single extraction techniques. Incubation experiments were conducted by mixing 0-5% powdered eggshell waste and curing the soil (1,246 mg Pb kg⁻¹ soil and 17 mg Cd kg⁻¹ soil) for 30 days. Five extractants, 0.01 M calcium chloride (CaCl₂), 1 M CaCl₂, 0.1 M hydrochloric acid (HCl), 0.43 M acetic acid (CH₃COOH), and 0.05 M ethylendiaminetetraacetic acid (EDTA), were used to determine the extractability of Cd and Pb following treatments with CaCO₃ and eggshell waste. Generally, the extractability of Cd and Pb in the soils decreased in response to treatments with CaCO₃ and eggshell waste, regardless of extractant. Using CaCl₂ extraction, the lowest Cd concentration was achieved upon both CaCO₃ and eggshell waste treatments, while the lowest Pb concentration was observed using HCl extraction. The highest amount of immobilized Cd and Pb was extracted by CH₃COOH or EDTA in soils treated with CaCO₃ and eggshell waste, indicating that remobilization of Cd and Pb may occur under acidic conditions. Based on the findings obtained, eggshell waste can be used as an alternative to CaCO₃ for the immobilization of heavy metals in soils.

Assessing soil pollution from a municipal waste dump in Islamabad, Pakistan. A study by INAA and AAS

International Nuclear Information System (INIS)

Waheed, S.; Siddique, N.

2010-01-01

INAA and AAS techniques have been employed to determine 40 elements in soil of a municipal waste dump in sector H-11, Islamabad. Background soil was also analyzed to study the extent of contamination of the dump site soil. Most of the major elements in these soils represented the geochemical composition of the soil in this area. The enrichment factors for quantified elements identified high Sb and Mg contents that could be attributed to the presence of PET and food materials in the waste. Geo-accumulation Index (I geo ), Pollution Index (PI) and the Integrated Pollution Index (IPI) have also been calculated for all elements. The values for these indices show that municipal waste has distorted the soil ambiance and the soil of waste dump site is slightly to moderately polluted as compared to the background soil. The dump soil was found to be moderately polluted by the elements Ba, Br, Ga, Rb, Zn, Ni and Pb. Significantly high Cu, Mg and Sb contamination was observed for the waste soil that is likely to pose an environmental issue if current waste disposal procedures are continuously employed. (author)

Inline Monitors for Measuring Cs-137 in the SRS Caustic Side Solvent Extraction Process

Energy Technology Data Exchange (ETDEWEB)

Casella, V

2006-04-24

The Department of Energy (DOE) selected Caustic-Side Solvent Extraction (CSSX) as the preferred technology for the removal of radioactive cesium from High-Level Waste (HLW) at the Savannah River Site (SRS). Before the full-scale Salt Waste Processing Facility (SWPF) becomes operational, a portion of dissolved saltcake waste will be processed through a Modular CSSX Unit (MCU). The MCU employs the CSSX process, a continuous process that uses a novel solvent to extract cesium from waste and concentrate it in dilute nitric acid. Of primary concern is Cs-137 which makes the solution highly radioactive. Since the MCU does not have the capacity to wait for sample results while continuing to operate, the Waste Acceptance Strategy is to perform inline analyses. Gamma-ray monitors are used to: measure the Cs-137 concentration in the decontaminated salt solution (DSS) before entering the DSS Hold Tank; measure the Cs-137 concentration in the strip effluent (SE) before entering the SE Hold Tank; and verify proper operation of the solvent extraction system by verifying material balance within the process. Since this gamma ray monitoring system application is unique, specially designed shielding was developed and software was written and acceptance tested by Savannah River National Laboratory (SRNL) personnel. The software is a LabView-based application that serves as a unified interface for controlling the monitor hardware and communicating with the host Distributed Control System. This paper presents the design, fabrication and implementation of this monitoring system.

Use of kaolin waste for production os soil-lime blocks

International Nuclear Information System (INIS)

Anjos, C.M. dos; Neves, G.A.

2011-01-01

There is an evident growth in waste generation over the last decades, especially in developing countries. The mining industry produces large quantities and different kinds and levels of dangerousness, such as the kaolin processing industry, which produces waste based on silica, mica and kaolinite. Disposal of this material in an inappropriate location causes significant environmental impacts, which could be minimized with the use of waste as raw material for use in construction. This paper has as main objective to study the incorporation of the kaolin processing waste into soil-lime. The residues of kaolin were calcined at a temperature of 800 ° C for evaluation of pozzolanic activity. Raw materials and conventional alternatives were characterized by means of test particle size analysis by laser diffraction, chemical analysis, X-ray diffraction. Then, blocks conventional soil-lime and soil-lime with the introduction of residual kaolin in proportions of 10%, 20%, 30% and 40% were cast and cured in a moist chamber for periods of 28, 60 and 90 days. The technological tests of compressive strength results obtained within the specifications of the ABNT. The best results were for 90 days of healing and 20% residue. (author)

Test Procedure - pumping system for caustic addition project

International Nuclear Information System (INIS)

Leshikar, G.A.

1994-01-01

This test procedure provides the requirements for sub-system testing and integrated operational testing of the submersible mixer pump and caustic addition equipment by WHC and Kaiser personnel at the Rotating Equipment Shop run-in pit (Bldg. 272E)

Co-treatment of spent cathode carbon in caustic and acid leaching process under ultrasonic assisted for preparation of SiC.

Science.gov (United States)

Yuan, Jie; Xiao, Jin; Li, Fachuang; Wang, Bingjie; Yao, Zhen; Yu, Bailie; Zhang, Liuyun

2018-03-01

Spent cathode carbon (SCC) from aluminum electrolysis has been treated in ultrasonic-assisted caustic leaching and acid leaching process, and purified SCC used as carbon source to synthesize silicon carbide (SiC) was investigated. Chemical and mineralogical properties have been characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and thermogravimetry and differential scanning calorimetry (TGA-DSC). Various experimental factors temperature, time, liquid-solid ratio, ultrasonic power, and initial concentration of alkali or acid affecting on SCC leaching result were studied. After co-treatment with ultrasonic-assisted caustic leaching and acid leaching, carbon content of leaching residue was 97.53%. SiC power was synthesized by carbothermal reduction at 1600 °C, as a result of yield of 76.43%, and specific surface area of 4378 cm 2 /g. This is the first report of using purified SCC and gangue to prepare SiC. The two industrial wastes have been used newly as secondary sources. Furthermore, ultrasonic showed significant effect in SCC leaching process. Copyright © 2017 Elsevier B.V. All rights reserved.

Prediction of complications following caustic ingestion in adults

DEFF Research Database (Denmark)

Christesen, H B

1995-01-01

The records of 86 adults admitted to hospital following caustic ingestion were reviewed. Eighteen patients (21%) developed complications; of these, six were fatal. Patients without symptoms or signs did not develop complications. Complications occurred only following lye ingestion, or intentional...

DEMONSTRATION OF THE NEXT-GENERATION CAUSTIC-SIDE SOLVENT EXTRACTION SOLVENT WITH 2-CM CENTRIFUGAL CONTRACTORS USING TANK 49H WASTE AND WASTE SIMULANT

Energy Technology Data Exchange (ETDEWEB)

Pierce, R.; Peters, T.; Crowder, M.; Caldwell, T.; Pak, D; Fink, S.; Blessing, R.; Washington, A.

2011-09-27

Researchers successfully demonstrated the chemistry and process equipment of the Caustic-Side Solvent Extraction (CSSX) flowsheet using MaxCalix for the decontamination of high level waste (HLW). The demonstration was completed using a 12-stage, 2-cm centrifugal contactor apparatus at the Savannah River National Laboratory (SRNL). This represents the first CSSX process demonstration of the MaxCalix solvent system with Savannah River Site (SRS) HLW. Two tests lasting 24 and 27 hours processed non-radioactive simulated Tank 49H waste and actual Tank 49H HLW, respectively. Conclusions from this work include the following. The CSSX process is capable of reducing {sup 137}Cs in high level radioactive waste by a factor of more than 40,000 using five extraction, two scrub, and five strip stages. Tests demonstrated extraction and strip section stage efficiencies of greater than 93% for the Tank 49H waste test and greater than 88% for the simulant waste test. During a test with HLW, researchers processed 39 liters of Tank 49H solution and the waste raffinate had an average decontamination factor (DF) of 6.78E+04, with a maximum of 1.08E+05. A simulant waste solution ({approx}34.5 liters) with an initial Cs concentration of 83.1 mg/L was processed and had an average DF greater than 5.9E+03, with a maximum DF of greater than 6.6E+03. The difference may be attributable to differences in contactor stage efficiencies. Test results showed the solvent can be stripped of cesium and recycled for {approx}25 solvent turnovers without the occurrence of any measurable solvent degradation or negative effects from minor components. Based on the performance of the 12-stage 2-cm apparatus with the Tank 49H HLW, the projected DF for MCU with seven extraction, two scrub, and seven strip stages operating at a nominal efficiency of 90% is {approx}388,000. At 95% stage efficiency, the DF in MCU would be {approx}3.2 million. Carryover of organic solvent in aqueous streams (and aqueous in organic

The Influence of Cattle Wastes on Degraded Savanna Soils of ...

African Journals Online (AJOL)

This paper examines the effects of cattle wastes on degraded savanna soils of Kwara State, Nigeria. A total of 40 soil samples were systematically collected from five quadrats of 12m x 12m. In 4 identified cattle sheds and 1 in adjacent fallow land (control field) on the same soil, climatic type and ecological zone. Standard ...

Cyprodinil retention on mixtures of soil and solid wastes from wineries. Effects of waste dose and ageing

DEFF Research Database (Denmark)

Rodriguez-Salgado, I.; Paradelo Pérez, Marcos; Pérez-Rodríguez, P.

2014-01-01

In spite of its wide-world economic relevance, wine production generates a huge amount of waste that threatens the environment. A batch experiment was designed to assess the effect of the amendment of an agricultural soil with two winery wastes (perlite and bentonite wastes) in the immobilization...... increased. The use of these winery wastes contributes to a more sustainable agriculture preventing fungicide mobilization to groundwater....

Biological Treatment of Petroleum in Radiologically Contaminated Soil

Energy Technology Data Exchange (ETDEWEB)

BERRY, CHRISTOPHER

2005-11-14

This chapter describes ex situ bioremediation of the petroleum portion of radiologically co-contaminated soils using microorganisms isolated from a waste site and innovative bioreactor technology. Microorganisms first isolated and screened in the laboratory for bioremediation of petroleum were eventually used to treat soils in a bioreactor. The bioreactor treated soils contaminated with over 20,000 mg/kg total petroleum hydrocarbon and reduced the levels to less than 100 mg/kg in 22 months. After treatment, the soils were permanently disposed as low-level radiological waste. The petroleum and radiologically contaminated soil (PRCS) bioreactor operated using bioventing to control the supply of oxygen (air) to the soil being treated. The system treated 3.67 tons of PCRS amended with weathered compost, ammonium nitrate, fertilizer, and water. In addition, a consortium of microbes (patent pending) isolated at the Savannah River National Laboratory from a petroleum-contaminated site was added to the PRCS system. During operation, degradation of petroleum waste was accounted for through monitoring of carbon dioxide levels in the system effluent. The project demonstrated that co-contaminated soils could be successfully treated through bioventing and bioaugmentation to remove petroleum contamination to levels below 100 mg/kg while protecting workers and the environment from radiological contamination.

New strategies for treatment and reuse of spent sulfidic caustic stream from petroleum industry

Directory of Open Access Journals (Sweden)

Jéssica Frontino Paulino

2012-01-01

Full Text Available This work examines traditional and new routes for removal of H2S and other sulfur compounds from spent sufidic caustic (SSC. SH- (hydrogenosulfide and S2- (sulfide ions were quantitatively oxidized at 25 ºC using H2O2, NaOCl or a spent sulfochromic mixture. SH-/S2- ions were also removed via reaction with freshly prepared iron or manganese hydroxides, or after passing the SSC through strong basic anion exchange resins (OH- form. The treated caustic solution, as well as iron/manganese hydroxides, removed H2S from diesel samples at 25 ºC. SSC treatment via strong basic anion-exchange resins produced the treated caustic solution with the highest free alkalinity.

Chemical and microbial remediation of hexavalent chromium from contaminated soil and mining/metallurgical solid waste: a review.

Science.gov (United States)

Dhal, B; Thatoi, H N; Das, N N; Pandey, B D

2013-04-15

Chromium is a highly toxic non-essential metal for microorganisms and plants, and its occurrence is rare in nature. Lower to higher chromium containing effluents and solid wastes released by activities such as mining, metal plating, wood preservation, ink manufacture, dyes, pigments, glass and ceramics, tanning and textile industries, and corrosion inhibitors in cooling water, induce pollution and may cause major health hazards. Besides, natural processes (weathering and biochemical) also contribute to the mobility of chromium which enters in to the soil affecting the plant growth and metabolic functions of the living species. Generally, chemical processes are used for Cr- remediation. However, with the inference derived from the diverse Cr-resistance mechanism displayed by microorganisms and the plants including biosorption, diminished accumulation, precipitation, reduction of Cr(VI) to Cr(III), and chromate efflux, bioremediation is emerging as a potential tool to address the problem of Cr(VI) pollution. This review focuses on the chemistry of chromium, its use, and toxicity and mobility in soil, while assessing its concentration in effluents/wastes which becomes the source of pollution. In order to conserve the environment and resources, the chemical/biological remediation processes for Cr(VI) and their efficiency have been summarised in some detail. The interaction of chromium with various microbial/bacterial strains isolated and their reduction capacity towards Cr(VI) are also discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

40 CFR 268.32 - Waste specific prohibitions-Soils exhibiting the toxicity characteristic for metals and...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Waste specific prohibitions-Soils... Prohibitions on Land Disposal § 268.32 Waste specific prohibitions—Soils exhibiting the toxicity characteristic... from land disposal: any volumes of soil exhibiting the toxicity characteristic solely because of the...

Metabolic and phylogenetic analysis of microbial communities during phytoremediation of soil contaminated with weathered hydrocarbons and heavy metals.

Science.gov (United States)

Palmroth, Marja R T; Koskinen, Perttu E P; Kaksonen, Anna H; Münster, Uwe; Pichtel, John; Puhakka, Jaakko A

2007-12-01

In the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation was studied. The relationship of functional diversity, measured as carbon source utilisation in Biolog plates and extracellular enzymatic activities, and genetic diversity of bacteria was evaluated. Denaturing gradient gel electrophoresis was used for community analyses at the species level. Bulk soil and rhizosphere soil from pine and poplar plantations were analysed separately to determine if the plant rhizosphere impacted hydrocarbon degradation. Prevailing microbial communities in the field site were both genetically and metabolically diverse. Furthermore, both tree rhizosphere and fertilisation affected the compositions of these communities and increased activities of extracellular aminopeptidases. In addition, the abundance of alkane hydroxylase and naphthalene dioxygenase genes in the communities was low, but the prevalence of these genes was increased by the addition of bioavailable hydrocarbons. Tree rhizosphere communities had greater hydrocarbon degradation potential than those of bulk soil. Hydrocarbon utilising communities were dominated generally by the species Ralstonia eutropha and bacteria belonging to the genus Burkholderia. Despite the presence of viable hydrocarbon-degrading microbiota, decomposition of hydrocarbons from weathered hydrocarbon contaminated soil over four years, regardless of the presence of vegetation, was low in unfertilised soil. Compost addition enhanced the removal of hydrocarbons.

Application of poultry processing industry waste: a strategy for vegetation growth in degraded soil.

Science.gov (United States)

do Nascimento, Carla Danielle Vasconcelos; Pontes Filho, Roberto Albuquerque; Artur, Adriana Guirado; Costa, Mirian Cristina Gomes

2015-02-01

The disposal of poultry processing industry waste into the environment without proper care, can cause contamination. Agricultural monitored application is an alternative for disposal, considering its high amount of organic matter and its potential as a soil fertilizer. This study aimed to evaluate the potential of poultry processing industry waste to improve the conditions of a degraded soil from a desertification hotspot, contributing to leguminous tree seedlings growth. The study was carried out under greenhouse conditions in a randomized blocks design and a 4 × 2 factorial scheme with five replicates. The treatments featured four amounts of poultry processing industry waste (D1 = control 0 kg ha(-1); D2 = 1020.41 kg ha(-1); D3 = 2040.82 kg ha(-1); D4 = 4081.63 kg ha(-1)) and two leguminous tree species (Mimosa caesalpiniaefolia Benth and Leucaena leucocephala (Lam.) de Wit). The poultry processing industry waste was composed of poultry blood, grease, excrements and substances from the digestive system. Plant height, biomass production, plant nutrient accumulation and soil organic carbon were measured forty days after waste application. Leguminous tree seedlings growth was increased by waste amounts, especially M. caesalpiniaefolia Benth, with height increment of 29.5 cm for the waste amount of 1625 kg ha(-1), and L. leucocephala (Lam.) de Wit, with maximum height increment of 20 cm for the waste amount of 3814.3 kg ha(-1). M. caesalpiniaefolia Benth had greater initial growth, as well as greater biomass and nutrient accumulation compared with L. leucocephala (Lam.) de Wit. However, belowground biomass was similar between the evaluated species, resulting in higher root/shoot ratio for L. leucocephala (Lam.) de Wit. Soil organic carbon did not show significant response to waste amounts, but it did to leguminous tree seedlings growth, especially L. leucocephala (Lam.) de Wit. Poultry processing industry waste contributes to leguminous tree seedlings growth

Use of mixed solid waste as a soil amendment for saline-sodic soil remediation and oat seedling growth improvement.

Science.gov (United States)

Fan, Yuan; Ge, Tian; Zheng, Yanli; Li, Hua; Cheng, Fangqin

2016-11-01

Soil salinization has become a worldwide problem that imposes restrictions on crop production and food quality. This study utilizes a soil column experiment to address the potential of using mixed solid waste (vinegar residue, fly ash, and sewage sludge) as soil amendment to ameliorate saline-sodic soil and enhance crop growth. Mixed solid waste with vinegar residue content ranging from 60-90 %, sewage sludge of 8.7-30 %, and fly ash of 1.3-10 % was added to saline-sodic soil (electrical conductivity (EC 1:5 ) = 1.83 dS m -1 , sodium adsorption ratio (SAR 1:5 ) = 129.3 (mmol c L -1 ) 1/2 , pH = 9.73) at rates of 0 (control), 130, 260, and 650 kg ha -1 . Results showed that the application of waste amendment significantly reduced SAR, while increasing soil soluble K + , Ca 2+ , and Mg 2+ , at a dose of 650 kg ha -1 . The wet stability of macro-aggregates (>1 mm) was improved 90.7-133.7 % when the application rate of amendment was greater than 260 kg ha -1 . The application of this amendment significantly reduced soil pH. Germination rates and plant heights of oats were improved with the increasing rate of application. There was a positive correlation between the percentage of vinegar residue and the K/Na ratio in the soil solutions and roots. These findings suggest that applying a mixed waste amendment (vinegar residue, fly ash, and sewage sludge) could be a cost-effective method for the reclamation of saline-sodic soil and the improvement of the growth of salt-tolerant plants.

Location-Related Differences in Weathering Behaviors and Populations of Culturable Rock-Weathering Bacteria Along a Hillside of a Rock Mountain.

Science.gov (United States)

Wang, Qi; Wang, Rongrong; He, Linyan; Sheng, Xiafang

2017-05-01

Bacteria play important roles in rock weathering, elemental cycling, and soil formation. However, little is known about the weathering potential and population of bacteria inhabiting surfaces of rocks. In this study, we isolated bacteria from the top, middle, and bottom rock samples along a hillside of a rock (trachyte) mountain as well as adjacent soils and characterized rock-weathering behaviors and populations of the bacteria. Per gram of rock or surface soil, 10 6 -10 7 colony forming units were obtained and total 192 bacteria were isolated. Laboratory rock dissolution experiments indicated that the proportions of the highly effective Fe (ranging from 67 to 92 %), Al (ranging from 40 to 48 %), and Cu (ranging from 54 to 81 %) solubilizers were significantly higher in the top rock and soil samples, while the proportion of the highly effective Si (56 %) solubilizers was significantly higher in the middle rock samples. Furthermore, 78, 96, and 6 % of bacteria from the top rocks, soils, and middle rocks, respectively, significantly acidified the culture medium (pH bacteria (79 %) from the rocks were different to those from the soils and most of them (species level) have not been previously reported. Furthermore, location-specific rock-weathering bacterial populations were found and Bacillus species were the most (66 %) frequently isolated rock-weathering bacteria in the rocks based on cultivation methods. Notably, the top rocks and soils had the highest and lowest diversity of rock-weathering bacterial populations, respectively. The results suggested location-related differences in element (Si, Al, Fe, and Cu) releasing effectiveness and communities of rock-weathering bacteria along the hillside of the rock mountain.

Secondary wastes and treatment of effluents from leaching of uranium from soils

International Nuclear Information System (INIS)

Ally, M.R.; Wilson, J.H.; Francis, C.W.

1993-01-01

The Department of Energy's Feed Materials and Production Center at Fernald, Ohio has over two million cubic meters of soil contaminated with Uranium which must be cleaned. Soil characterization studies show that Uranium is unevenly distributed between the clay, sand and silt fractions. This paper examines the option of using leaching agents to remove Uranium from the soil and the treatment of secondary wastes. Results of the effects of various leachants in removing Uranium and the complications of co-leaching minerals/organic matter that are important for maintaining soil integrity and structure shall be discussed. Candidate leachants must remove the Uranium level below 35pCi/g of soil and produce a secondary waste that is amenable to on-site treatment at reasonable cost

Effect of Die Head Temperature at Compounding Stage on the Degradation of Linear Low Density Polyethylene/Plastic Film Waste Blends after Accelerated Weathering

Directory of Open Access Journals (Sweden)

S. M. Al-Salem

2016-01-01

Full Text Available Accelerated weathering test was performed on blends of linear low density polyethylene (LLDPE and plastic film waste constituting the following percentages of polyolefin polymers (wt.%: LLDPE (46%, low density polyethylene (LDPE, 51%, high density polyethylene (HDPE, 1%, and polypropylene (PP, 2%. Compounded blends were evaluated for their mechanical and physical (optical properties. The impact of photodegradation on the formulated blends was studied, and loss of mechanical integrity was apparent with respect to both the exposure duration to weathering and waste content. The effect of processing conditions, namely, the die head temperature (DHT of the blown-film assembly used, was investigated in this work. It was witnessed that surpassing the melting point of the blends constituting polymers did not always result in a synergistic behaviour between polymers. This was suspected to be due to the loss of amorphous region that polyolefin polymers get subjected to with UV exposure under weathering conditions and the effect of the plastic waste constituents. The total change in colour (ΔE did not change with respect to DHT or waste content due to rapid change degradation on the material’s surface. Haze (% and light transmission (% decreased with the increase in waste content which was attributed to lack of miscibility between constituting polymers.

Comparison of soil heavy metal pollution caused by e-waste recycling activities and traditional industrial operations.

Science.gov (United States)

He, Kailing; Sun, Zehang; Hu, Yuanan; Zeng, Xiangying; Yu, Zhiqiang; Cheng, Hefa

2017-04-01

The traditional industrial operations are well recognized as an important source of heavy metal pollution, while that caused by the e-waste recycling activities, which have sprouted in some developing countries, is often overlooked. This study was carried out to compare the status of soil heavy metal pollution caused by the traditional industrial operations and the e-waste recycling activities in the Pearl River Delta, and assess whether greater attention should be paid to control the pollution arising from e-waste recycling activities. Both the total contents and the chemical fractionation of major heavy metals (As, Cr, Cd, Ni, Pb, Cu, and Zn) in 50 surface soil samples collected from the e-waste recycling areas and 20 soil samples from the traditional industrial zones were determined. The results show that the soils in the e-waste recycling areas were mainly polluted by Cu, Zn, As, and Cd, while Cu, Zn, As, Cd, and Pb were the major heavy metals in the soils from the traditional industrial zones. Statistical analyses consistently show that Cu, Cd, Pb, and Zn in the surface soils from both types of sites were contributed mostly by human activities, while As, Cr, and Ni in the soils were dominated by natural background. No clear distinction was found on the pollution characteristic of heavy metals in the surface soils between the e-waste recycling areas and traditional industrial zones. The potential ecological risk posed by heavy metals in the surface soils from both types of sites, which was dominated by that from Cd, ranged from low to moderate. Given the much shorter development history of e-waste recycling and its largely unregulated nature, significant efforts should be made to crack down on illegal e-waste recycling and strengthen pollution control for related activities.

Filtration and Leach Testing for PUREX Cladding Sludge and REDOX Cladding Sludge Actual Waste Sample Composites

Energy Technology Data Exchange (ETDEWEB)

Shimskey, Rick W.; Billing, Justin M.; Buck, Edgar C.; Casella, Amanda J.; Crum, Jarrod V.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hallen, Richard T.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Swoboda, Robert G.

2009-03-02

A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan (Barnes and Voke 2006). The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Hanford Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Under test plan TP RPP WTP 467 (Fiskum et al. 2007), eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. Under this test plan, a waste testing program was implemented that included: • Homogenizing the archive samples by group as defined in the test plan. • Characterizing the homogenized sample groups. • Performing parametric leaching testing on each group for compounds of interest. • Performing bench-top filtration/leaching tests in the hot cell for each group to simulate filtration and leaching activities if they occurred in the UFP2 vessel of the WTP Pretreatment Facility. This report focuses on a filtration/leaching test performed using two of the eight waste composite samples. The sample groups examined in this report were the plutonium-uranium extraction (PUREX) cladding waste sludge (Group 3, or CWP) and reduction-oxidation (REDOX) cladding waste sludge (Group 4, or CWR). Both the Group 3 and 4 waste composites were anticipated to be high in gibbsite, thus requiring caustic leaching. WTP RPT 167 (Snow et al. 2008) describes the homogenization, characterization, and parametric leaching activities before benchtop filtration/leaching testing of these two waste groups. Characterization and initial parametric data in that report were used to plan a single filtration/leaching test using a blend of both wastes. The test focused on filtration testing of the waste and caustic leaching for aluminum, in the form

Examination plan for the soils and low-level radioactive waste forms of the NRC field testing lysimeters

International Nuclear Information System (INIS)

McConnell, J.W. Jr.; Rogers, R.D.; Jastrow, J.D.

1996-01-01

The Field Lysimeter Investigations: Low-Level Waste Data Base Development Program is obtaining information on the performance of radioactive waste forms. These experiments were recently shut down and have been examined in accordance with a detailed waste form and soil sampling plan. Ion-exchange resins from a commercial nuclear power station were solidified into waste forms using portland cement and vinyl ester-styrene. These waste forms were tested to (a) obtain information on performance of waste forms in typical disposal environments, (b) compare field results with bench leach studies, (c) develop a low-level waste data base for use in performance assessment source term calculations, and (d) apply the DUST computer code to compare predicted cumulative release to actual field data. The program, funded by the Nuclear Regulatory Commission (NRC), includes observed radionuclide releases from waste forms at two test sites over 10 years of successful operation. Lysimeters are ideal systems for obtaining actual field test data because, when properly designed and operated, they can be used to isolate soil and waste systems under actual environmental conditions. The purpose of this paper is to present the experimental plan for the examination of the waste forms and soils of the two lysimeter arrays, which have now been shut down. Vertical soil cores have been taken from the soil columns and will be analyzed with radiochemistry to define movement of radionuclides after release from the waste forms. A comparison is made of the DUST-predicted releases to those previously determined and reported from the lysimeter leachate analyses. That comparison uses new partition coefficients (Kd) recently obtained from laboratory analysis of the lysimeter soils and sand. Those DUST code results also will be compared to actual radionuclide movements through the soil columns as determined from soil core analysis

Permanent radiation and weather monitoring systems at the Posiva nuclear waste facilities

International Nuclear Information System (INIS)

Laukkanen, J.; Palomaeki, M.; Viitanen, P.; Kumpula, L.

2012-12-01

Posiva Oy is planning to build a complex of two nuclear waste facilities in Olkiluoto. The facilities will encapsulate and dispose the spent nuclear fuel from the nuclear power plants operated by Posiva's owners into Olkiluoto bedrock. The spent fuel is strongly radioactive, so the radiation safety of the facilities and their processes for its users and the environment must be ensured. This paper deals with of the stationary radiation and weather measurement systems designed for the monitoring of Posiva's nuclear waste facilities and their processes. The systems are used for monitoring the encapsulation and disposal facilities and processes, as well as the emissions to the environment. The document collects also the system design basis and other requirements to be considered in the design of these systems at this early stage. (orig.)

Importance of microscopy in durability studies of solidified and stabilized contaminated soils

Science.gov (United States)

Klich, I.; Wilding, L.P.; Drees, L.R.; Landa, E.R.

1999-01-01

Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical, thermal, or biological means. Despite the increased use of S/S technologies, little research has been conducted on the weathering and degradation of solidified and stabilized wastes once the treated materials have been buried. Published data to verify the performance and durability of landfilled treated wastes over time are rare. In this preliminary study, optical and electron microscopy (scanning electron microscopy [SEM], transmission electron microscopy [TEM] and electron probe microanalyses [EPMA]) were used to evaluate weathering features associated with metal-bearing contaminated soil that had been solidified and stabilized with Portland cement and subsequently buried on site, stored outdoors aboveground, or achieved in a laboratory warehouse for up to 6 yr. Physical and chemical alteration processes identified include: freeze-thaw cracking, cracking caused by the formation of expansive minerals such as ettringite, carbonation, and the movement of metals from waste aggregates into the cement micromass. Although the extent of degradation after 6 yr is considered slight to moderate, results of this study show that the same environmental concerns that affect the durability of concrete must be considered when evaluating the durability and permanence of the solidification and stabilization of contaminated soils with cement. In addition, such evaluations cannot be based on leaching and chemical analyses alone. The use of all levels of microscopic analyses must be incorporated into studies of the long-term performance of S/S technologies.Solidification/stabilization (S/S) is recognized by the U.S. EPA as a best demonstrated available technology for the containment of contaminated soils and other hazardous wastes that cannot be destroyed by chemical

Extraction of long-lived radionuclides from caustic Hanford tank waste supernatants

International Nuclear Information System (INIS)

Chaiko, D.J.; Mertz, C.J.; Vojta, Y.

1995-07-01

A series of polymer-based extraction systems, based on the use of polyethylene glycols (PEGs) or polypropylene glycols (PPGs), was demonstrated to be capable of selective extraction and recovery of long-lived radionuclides, such as 99 Tc and 129 I, from Hanford SY-101 tank waste, neutralized current acid waste, and single-shell tank waste simulants. During the extraction process, anionic species like TcO 4 - and I - are selectively transferred to the less dense PEG-rich aqueous phase. The partition coefficients for a wide range of inorganic cations and anions, such as sodium, potassium, aluminum, nitrate, nitrite, and carbonate, are all less than one. The partition coefficients for pertechnetate ranged from 12 to 50, depending on the choice of waste simulant and temperature. The partition coefficient for iodide was about 5, while that of iodate was about 0.25. Irradiation of the PEG phase with gamma-ray doses up to 20 Mrad had no detectable effect on the partition coefficients. The most selective extraction systems examined were those based on PPGs, which exhibited separation factors in excess of 3000 between TcO 4 - and NO 3 - /NO 2- . An advantage of the PPG-based system is minimization of secondary waste production. These studies also highlighted the need for exercising great care in extrapolating the partitioning behavior with tank waste simulants to actual tank waste

Cement conditioning of waste materials and polluted soil using the GEODUR process

International Nuclear Information System (INIS)

Brocdersen, K.; Hjelmar, O.; Mortonsen, S.

1991-01-01

In this paper two areas of application of the GEODUR additive in cement stabilization of waste materials have been investigated: stabilization of radioactive contaminated soil and stabilization of municipal solid waste incinerator ash. Preliminary experimental work on a clayey soil contaminated with radioactive cesium and strontium has indicated that the GEODUR process is a technically feasible method for soil solidification. The retarding effects of humic materials in the soil are eliminated by the additive even at low cement contents. The solidified soil is not particularly strong, but that satisfactory water permeability. Retention of cesium is reasonably good, but not as good as for the untreated soil. Retention of strontium is not good but is considerably improved by carbonation. The volume stability during permanent immersion of the solidified products in water is satisfactory, but crack formation during dryout cannot be excluded

Impact of Waste Materials and Organic Amendments on Soil Properties and Vegetative Performance

Directory of Open Access Journals (Sweden)

Steven L. McGeehan

2012-01-01

Full Text Available Waste materials, and materials derived from wastes, possess many characteristics that can improve soil fertility and enhance crop performance. These materials can be particularly useful as amendments to severely degraded soils associated with mining activities. This study evaluated biosolids, composts, log yard wastes, and two organic soil treatments for improved soil fertility and vegetative performance using side-by-side comparisons. Each plot was seeded with a standardized seed mix and evaluated for a series of soil chemical and physical parameters, total vegetation response, species diversity, ecological plant response, and invasion indices. All treatments were successful at improving soil fertility and promoting a self-sustaining vegetative cover. The level of available nitrogen had a strong impact on vegetative coverage, species distribution, and extent of unseeded vegetation. For example, high nitrogen treatments promoted a grass-dominated (low forb plant community with a low content of unseeded vegetation. In contrast, low nitrogen treatments promoted a more balanced plant community with a mixture of grass and forb species and greater susceptibility to unseeded vegetation establishment.

Laser Beam Caustic Measurement with Focal Spot Analyser

DEFF Research Database (Denmark)

Olsen, Flemming Ove; Gong, Hui; Bagger, Claus

2005-01-01

In industrial applications of high power CO2-lasers the caustic characteristics of the laser beam have great effects on the performance of the lasers. A welldefined high intense focused spot is essential for reliable production results. This paper presents a focal spot analyser that is developed...

Utilization of Agricultural Wastes in Stabilization of Landfill Soil

Directory of Open Access Journals (Sweden)

Nidzam Rahmat Mohamad

2014-01-01

Full Text Available Palm Oil Fuel Ash (POFA and Rice Husk Ash (RHA are local agricultural waste material from Palm Oil Industry and from Paddy Industry in Malaysia. Currently, the disposal of these ashes from a burning process is a problem to both industries, and hence leads to environmental pollution. The main aim of this research was to investigate the potential of utilizing POFA and RHA as sustainable stabilizer material as partial replacement of traditional one which is lime and Portland Cement (PC. Laboratory investigations were carried out to establish the potential utilization of Malaysian Agricultural wastes POFA and RHA in stabilizing Teluk Kapas Landfill soil. Landfill soil on its own and combination with laterite clay soil were stabilized using POFA or RHA either on its own or in combination with Lime or Portland Cement (PC. The traditional stabilizers of lime or Portland Cement (PC were used as controls. Compacted cylinder test specimens were made at typical stabilizer contents and moist cured for up to 60 days prior to testing for compressive and water absorption tests. The results obtained showed that landfill soil combined with laterite clay (50:50 stabilized with 20% RHA:PC (50:50and POFA: PC (50:50 recorded the highest values of compressive strength compared to the other compositions of stabilizers and soils. However, when the amount of POFA and RHA increased in the system the compressive strength values of the samples tends to increase. These results suggest technological, economic as well as environmental advantages of using POFA and RHA and similar industrial by-products to achieve sustainable infrastructure development with near zero industrial waste.

Optimising the bio-piling of weathered hydrocarbons within a risk management framework

International Nuclear Information System (INIS)

Hough, R.; Brassington, K.; Sinke, A.; Crossley, J.; Paton, G.; Semple, K.; Risdon, G.; Jacobson, Ch.; Daly, P.; Jackman, S.; Lethbridge, G.; Pollard, S.

2005-01-01

Thirty years of research into petroleum microbiology and bio-remediation have bypassed an important observation - that many hydrocarbon contaminated sites posing potential risks to human health harbour weathered, 'mid-distillate' or heavy oils rather than 'fresh product'. Ex-situ bio-piling is an important technology for treating soils contaminated with weathered hydrocarbons. However, its performance continues to be represented by reference to reductions in the hydrocarbon 'load' in the soils being treated, rather than reductions in the risks posed by the hydrocarbon contamination. The absence of 'risk' from the vocabulary of many operators and remediation projects reduces stakeholder (regulatory, investor, landowner, and public) confidence in remediation technologies, and subsequently limits the market potential of these technologies. Stakeholder confidence in the bio-piling of weathered hydrocarbons may be improved by demonstrating process optimisation within a validated risk management framework. To address these issues, a consortium led by Cranfield University's Integrated Waste Management Centre has secured funding from the UK Government's Bio-remediation LINK programme. Project PROMISE (involving BP, SecondSite Regeneration Ltd., Dew Remediation Ltd., TES Bretby (Mowlem Group), technology translators PERA, and academics from Aberdeen, Cranfield and Lancaster Universities) aims to improve market confidence in bio-piling by demonstrating how this treatment may be applied within a risk management context. For weathered hydrocarbons in particular, the underpinning scientific components of process control, waste diagnostics, environmental fate modelling, and risk assessment have yet to be fully integrated to allow bio-piling projects to be verified with improved confidence. The Joint Research Council Review of Bio-remediation recognised this in calling explicitly for the positioning of bio-remediation within a risk management framework. The PERF report (Thermo

Control of aromatic-waste air streams by soil bioreactors

International Nuclear Information System (INIS)

Miller, D.E.; Canter, L.W.

1991-01-01

Contamination of groundwater resources is a serious environmental problem which is continuing to increase in occurrence in the United States. It has been reported that leaking underground gasoline storage tanks may pose the most serious threat of all sources of groundwater contamination. Gasolines are comprised of a variety of aliphatic and aromatic hydrocarbons. The aromatic portion consists primarily of benzene, toluene, ethylbenzene, and xylenes (BTEX compounds). BTEX compounds are also among the most frequency identified substances at Superfund sites. Pump and treat well systems are the most common and frequently used technique for aquifer restoration. Treatment is often in the form of air stripping to remove the volatile components from the contaminated water. Additionally, soil ventilation processes have been used to remove volatile components from the vadose zone. Both air stripping and soil ventilation produce a waste gas stream containing volatile compounds which is normally treated by carbon adsorption or incineration. Both treatment processes require a substantial capital investment and continual operation and maintenance expenditures. The objective of the study was to examine the potential of using soil bioreactors to treat a waste gas stream produced by air stripping or soil ventilation process. Previous studies have shown that various hydrocarbons can be successfully treated with soils. The study examined the removal of BTEX compounds within soil columns and the influence of soil type, inlet concentration, and inlet flow rate on the removal efficiency

Analyses of soils at commercial radioactive-waste-disposal sites

International Nuclear Information System (INIS)

Piciulo, P.L.; Shea, C.E.; Barletta, R.E.

1982-01-01

Brookhaven National Laboratory, in order to provide technical assistance to the NRC, has measured a number of physical and chemical characteristics of soils from two currently operating commercial radioactive waste disposal sites; one at Barnwell, SC, and the other near Richland, WA. Soil samples believed to be representative of the soil that will contact the buried waste were collected and analyzed. Earth resistivities (field measurements), from both sites, supply information to identify variations in subsurface material. Barnwell soil resistivities (laboratory measurements) range from 3.6 x 10 5 ohm-cm to 8.9 x 10 4 ohm-cm. Soil resistivities of the Hanford sample vary from 3.0 x 10 5 ohm-cm to 6.6 x 10 3 ohm-cm. The Barnwell and Hanford soil pH ranges from 4.8 to 5.4 and from 4.0 to 7.2 respectively. The pH of a 1:2 mixture of soil to 0.01 M CaCl 2 resulted in a pH for the Barnwell samples of 3.9 +- 0.1 and for the Hanford samples of 7.4 +- 0.2. These values are comparable to the pH measurements of the water extract of the soils used for the analyses of soluble ion content of the soils. The exchange acidity of the soils was found to be approximately 7 mg-eq per 100 g of dry soil for clay material from Barnwell, whereas the Hanford soils showed an alkaline reaction. Aqueous extracts of saturated pastes were used to determine the concentrations of the following ions: Ca 2+ , Mg 2+ , K + , Na + , HCO 3 - , SO 4 /sup =/, and Cl - . The sulfide content of each of the soils was measured in a 1:2.5 mixture of soil to an antioxidant buffer solution. The concentrations of soluble ions found in the soils from both sites are consistent with the high resistivities

Influence of lokpa cattle market wastes on agricultural soil quality ...

African Journals Online (AJOL)

Influence of lokpa cattle market wastes on agricultural soil quality. ... African Journal of Environmental Science and Technology ... Soil samples were collected from the Central, 3 and 6 m Northwards, Southwards, Eastwards and Westwards of Lokpa cattle market, Umuneochi Local Government Area of Abia State, Nigeria at ...

Atmospheric weathering and silica-coated feldspar: analogy with zeolite molecular sieves, granite weathering, soil formation, ornamental slabs, and ceramics.

Science.gov (United States)

Smith, J V

1998-03-31

Feldspar surfaces respond to chemical, biological, and mechanical weathering. The simplest termination is hydroxyl (OH), which interacts with any adsorption layer. Acid leaching of alkalis and aluminum generated a silica-rich, nanometers-thick skin on certain feldspars. Natural K, Na-feldspars develop fragile surfaces as etch pits expand into micrometer honeycombs, possibly colonized by lichens. Most crystals have various irregular coats. Based on surface-catalytic processes in molecular sieve zeolites, I proposed that some natural feldspars lose weakly bonded Al-OH (aluminol) to yield surfaces terminated by strongly bonded Si-OH (silanol). This might explain why some old feldspar-bearing rocks weather slower than predicted from brief laboratory dissolution. Lack of an Al-OH infrared frequency from a feldspar surface is consistent with such a silanol-dominated surface. Raman spectra of altered patches on acid-leached albite correspond with amorphous silica rather than hydroxylated silica-feldspar, but natural feldspar may respond differently. The crystal structure of H-exchanged feldspar provides atomic positions for computer modeling of complex ideas for silica-terminated feldspar surfaces. Natural weathering also depends on swings of temperature and hydration, plus transport of particles, molecules, and ionic complexes by rain and wind. Soil formation might be enhanced by crushing granitic outcrops to generate new Al-rich surfaces favorable for chemical and biological weathering. Ornamental slabs used by architects and monumental masons might last longer by minimizing mechanical abrasion during sawing and polishing and by silicifying the surface. Silica-terminated feldspar might be a promising ceramic surface.

Extraction of long-lived radionuclides from caustic Hanford tank waste supernatants

Energy Technology Data Exchange (ETDEWEB)

Chaiko, D.J.; Mertz, C.J.; Vojta, Y. [and others

1995-07-01

A series of polymer-based extraction systems, based on the use of polyethylene glycols (PEGs) or polypropylene glycols (PPGs), was demonstrated to be capable of selective extraction and recovery of long-lived radionuclides, such as {sup 99}Tc and {sup 129}I, from Hanford SY-101 tank waste, neutralized current acid waste, and single-shell tank waste simulants. During the extraction process, anionic species like TcO{sub 4}{sup {minus}} and I{sup {minus}} are selectively transferred to the less dense PEG-rich aqueous phase. The partition coefficients for a wide range of inorganic cations and anions, such as sodium, potassium, aluminum, nitrate, nitrite, and carbonate, are all less than one. The partition coefficients for pertechnetate ranged from 12 to 50, depending on the choice of waste simulant and temperature. The partition coefficient for iodide was about 5, while that of iodate was about 0.25. Irradiation of the PEG phase with gamma-ray doses up to 20 Mrad had no detectable effect on the partition coefficients. The most selective extraction systems examined were those based on PPGs, which exhibited separation factors in excess of 3000 between TcO{sub 4}{sup {minus}} and NO{sub 3}{sup {minus}}/NO{sub 2}{sub {minus}}. An advantage of the PPG-based system is minimization of secondary waste production. These studies also highlighted the need for exercising great care in extrapolating the partitioning behavior with tank waste simulants to actual tank waste.

Sorption study and contribution of ion exchange in the dynamics of 137Cs n highly weathered soils

International Nuclear Information System (INIS)

Nascimento Sobrinho, Guilherme Augusto

2014-01-01

The present study investigated the sorption kinetics and the reversibility of 137 Cs within highly weathered soils, by means of sorption isotherms and desorption with three concentrations of silver thiourea (AgTU). For this purpose, four soils were selected based on their mineralogy and pedogenetics and sampled from lysimeters placed within the experimental area of the Tropical Radioecology Laboratory of the Institute for Radioprotection and Dosimetry. Three of them were tropical soils, belonging to the Argissolo (ARG), Latossolo vermelho (LV) and Latossolo vermelho amarelo (LVA) classes, and one subtropical, belonging to the Nitossolo (NIT) class. The 'goodness-of-fit' of the constant partition, Langmuir and Freundlich isotherms to the experimental data were assessed by means of a 'traditional' approach, i.e. correlation (R) and determination (R 2 ) coefficients, and a 'theoretic-informative' one, based upon the Corrected Akaike Information Criteria (AICc). In this work became clear that even presenting high affinity for the soil surface, once the sorption equilibrium was reached within 24 h (66 to 97% of sorbed 137 Cs), quite a lot of this radionuclide remains easily mobile (40 to 73% of desorbed 137 Cs), by means of a single extraction with AgTU 0,05 mol.L-1, and that such reversibility relates in an inverse manner to the sorption capacity of the studied soils for 137 Cs. This work pointed also that the constant partition model, mostly known as Kdi, does not fit at all for the sorption data gathered for four highly weathered soils from four mineralogical groups, and for a very dilute solution of 137 Cs. The mathematical model that most adequately described the sorption data for the four studied soils was the Langmuir equation (R 2 > 0,95). The multi model analysis was not able to support generalizations for the four soils. The three models considered in this study provided good predictions of the sorbed 137 Cs for the ARG, LVA and NIT samples (ΔAICc AICc = 0

Caustic-Side Solvent Extraction: Prediction of Cesium Extraction from Actual Wastes and Actual Waste Simulants

International Nuclear Information System (INIS)

Delmau, L.H.; Haverlock, T.J.; Sloop, F.V. Jr.; Moyer, B.A.

2003-01-01

This report presents the work that followed the CSSX model development completed in FY2002. The developed cesium and potassium extraction model was based on extraction data obtained from simple aqueous media. It was tested to ensure the validity of the prediction for the cesium extraction from actual waste. Compositions of the actual tank waste were obtained from the Savannah River Site personnel and were used to prepare defined simulants and to predict cesium distribution ratios using the model. It was therefore possible to compare the cesium distribution ratios obtained from the actual waste, the simulant, and the predicted values. It was determined that the predicted values agree with the measured values for the simulants. Predicted values also agreed, with three exceptions, with measured values for the tank wastes. Discrepancies were attributed in part to the uncertainty in the cation/anion balance in the actual waste composition, but likely more so to the uncertainty in the potassium concentration in the waste, given the demonstrated large competing effect of this metal on cesium extraction. It was demonstrated that the upper limit for the potassium concentration in the feed ought to not exceed 0.05 M in order to maintain suitable cesium distribution ratios

The leaching of trace elements from municipal solid waste incinerator bottom ash at different stages of weathering

NARCIS (Netherlands)

Meima, J.A.; Comans, R.N.J.

1999-01-01

For a proper assessment of the environmental impact of the utilisation and disposal of Municipal Solid Waste Incinerator (MSWI) bottom ash it is necessary to understand weathering processes and their effects on (trace) element leaching. The authors have investigated the processes that control the

Expansive soil stabilization with coir waste and lime for flexible pavement subgrade

Science.gov (United States)

Narendra Goud, G.; Hyma, A.; Shiva Chandra, V.; Sandhya Rani, R.

2018-03-01

Expansive soil properties can be improved by various methods to make it suitable for construction of flexible pavement. The coir pith is the by-product (bio-waste) generated from coir industry during extraction of coir fiber from coconut husk. Openly disposed coir pith can make the surrounding areas unhygienic. This bio-waste can be one of the potential materials to stabilize the expansive soils. In the present study coir pith and lime are used as stabilizers. Different combinations of coir pith contents (1%, 2% and 3%) and lime contents (2%, 3% and 4%)are used to study the behavior of expansive soil. Unconfined compressive strength (UCS) of unstabilized and stabilized soils was determined. Optimum content of coir pith and lime are determined based on UCS of the soil. California bearing ratio of soil determined at optimum contents of coir pith and lime. Flexible pavement layer compositions for two levels of traffic using stabilized soil subgrade.

Co-digestion of municipal organic wastes with night soil and cow ...

African Journals Online (AJOL)

Aghomotsegin

a very promising way to overcome the problem of waste treatment. Biogas, which is principally ... as manure, night soil, sewage sludge and municipal solid wastes. Furthermore, the solid .... It is smokeless, hygienic and more convenient to use ...

Reduction of radioactive waste from remediation of uranium-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Kim, Il Gook; Kim, Seung Soo; Kim, Gye Nam; Han, Gyu Seong; Choi, Jong Won [Decontamination and Decommissioning Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-06-15

Great amounts of solid radioactive waste (second waste) and waste solution are generated from the remediation of uranium-contaminated soil. To reduce these, we investigated washing with a less acidic solution and recycling the waste solution after removal of the dominant elements and uranium. Increasing the pH of the washing solution from 0.5 to 1.5 would be beneficial in terms of economics. A high content of calcium in the waste solution was precipitated by adding sulfuric acid. The second waste can be significantly reduced by using sorption and desorption techniques on ampholyte resin S-950 prior to the precipitation of uranium at pH 3.0.

Reduction of radioactive waste from remediation of uranium-contaminated soil

International Nuclear Information System (INIS)

Kim, Il Gook; Kim, Seung Soo; Kim, Gye Nam; Han, Gyu Seong; Choi, Jong Won

2016-01-01

Great amounts of solid radioactive waste (second waste) and waste solution are generated from the remediation of uranium-contaminated soil. To reduce these, we investigated washing with a less acidic solution and recycling the waste solution after removal of the dominant elements and uranium. Increasing the pH of the washing solution from 0.5 to 1.5 would be beneficial in terms of economics. A high content of calcium in the waste solution was precipitated by adding sulfuric acid. The second waste can be significantly reduced by using sorption and desorption techniques on ampholyte resin S-950 prior to the precipitation of uranium at pH 3.0

Evaluating Weather Research and Forecasting Model Sensitivity to Land and Soil Conditions Representative of Karst Landscapes

Science.gov (United States)

Johnson, Christopher M.; Fan, Xingang; Mahmood, Rezaul; Groves, Chris; Polk, Jason S.; Yan, Jun

2018-03-01

Due to their particular physiographic, geomorphic, soil cover, and complex surface-subsurface hydrologic conditions, karst regions produce distinct land-atmosphere interactions. It has been found that floods and droughts over karst regions can be more pronounced than those in non-karst regions following a given rainfall event. Five convective weather events are simulated using the Weather Research and Forecasting model to explore the potential impacts of land-surface conditions on weather simulations over karst regions. Since no existing weather or climate model has the ability to represent karst landscapes, simulation experiments in this exploratory study consist of a control (default land-cover/soil types) and three land-surface conditions, including barren ground, forest, and sandy soils over the karst areas, which mimic certain karst characteristics. Results from sensitivity experiments are compared with the control simulation, as well as with the National Centers for Environmental Prediction multi-sensor precipitation analysis Stage-IV data, and near-surface atmospheric observations. Mesoscale features of surface energy partition, surface water and energy exchange, the resulting surface-air temperature and humidity, and low-level instability and convective energy are analyzed to investigate the potential land-surface impact on weather over karst regions. We conclude that: (1) barren ground used over karst regions has a pronounced effect on the overall simulation of precipitation. Barren ground provides the overall lowest root-mean-square errors and bias scores in precipitation over the peak-rain periods. Contingency table-based equitable threat and frequency bias scores suggest that the barren and forest experiments are more successful in simulating light to moderate rainfall. Variables dependent on local surface conditions show stronger contrasts between karst and non-karst regions than variables dominated by large-scale synoptic systems; (2) significant

Managing soil moisture on waste burial sites in arid regions

International Nuclear Information System (INIS)

Anderson, J.E.; Ratzlaff, T.D.; Nowak, R.S.; Markham, O.D.

1993-01-01

In semiarid regions, where potential evapotranspiration greatly exceeds precipitation, it is theoretically possible to preclude water form reaching interred wastes by (i) providing a sufficient cap of soil to store precipitation that falls while plants are dormant and (ii) establishing sufficient plant cover to deplete soil moisture during the growing season, thereby emptying the water storage reservoir of the soil. Here the authors discuss the theory and rationale for such an approach and then present the results of a field study to test its efficacy at the Idaho National Engineering Laboratory (INEL). They examined the capacity of four species of perennial plants to deplete soil moisture on simulated waste trenches and determined the effective water storage capacity of the soil. Those data enabled them to estimate the minimum depth of fill soil required to prevent deep drainage. Any of the species studied can use all of the plant-available soil water, even during a very wet growing season. The water storage capacity of the soil studied is 17% by volume, so a trench cap of 1.6 m of soil should be adequate to store precipitation received at the INEL while plants are dormant. They recommend a fill soil depth of 2 m to provide a margin of safety in case water accumulates in local areas as a result of heavy snow accumulation, subsidence, or runoff. Fill soil requirements and choice of plant species will vary, but the concepts and general approach are applicable to other shallow land burial sites in arid or semiarid regions. 23 refs., 5 figs

Bioremediation of oil-contaminated soil using Candida catenulata and food waste

International Nuclear Information System (INIS)

Joo, Hung-Soo; Ndegwa, Pius M.; Shoda, Makoto; Phae, Chae-Gun

2008-01-01

Even though petroleum-degrading microorganisms are widely distributed in soil and water, they may not be present in sufficient numbers to achieve contaminant remediation. In such cases, it may be useful to inoculate the polluted area with highly effective petroleum-degrading microbial strains to augment the exiting ones. In order to identify a microbial strain for bioaugmentation of oil-contaminated soil, we isolated a microbial strain with high emulsification and petroleum hydrocarbon degradation efficiency of diesel fuel in culture. The efficacy of the isolated microbial strain, identified as Candida catenulata CM1, was further evaluated during composting of a mixture containing 23% food waste and 77% diesel-contaminated soil including 2% (w/w) diesel. After 13 days of composting, 84% of the initial petroleum hydrocarbon was degraded in composting mixes containing a powdered form of CM1 (CM1-solid), compared with 48% of removal ratio in control reactor without inoculum. This finding suggests that CM1 is a viable microbial strain for bioremediation of oil-contaminated soil with food waste through composting processes. - Enhancement on degradation ability of petroleum hydrocarbon by the microbial strain in the composting process with food waste

Soil load above Hanford waste storage tanks (2 volumes)

International Nuclear Information System (INIS)

Pianka, E.W.

1995-01-01

This document is a compilation of work performed as part of the Dome Load Control Project in 1994. Section 2 contains the calculations of the weight of the soil over the tank dome for each of the 75-feet-diameter waste-storage tanks located at the Hanford Site. The chosen soil specific weight and soil depth measured at the apex of the dome crown are the same as those used in the primary analysis that qualified the design. Section 3 provides reference dimensions for each of the tank farm sites. The reference dimensions spatially orient the tanks and provide an outer diameter for each tank. Section 4 summarizes the available soil surface elevation data. It also provides examples of the calculations performed to establish the present soil elevation estimates. The survey data and other data sources from which the elevation data has been obtained are printed separately in Volume 2 of this Supporting Document. Section 5 contains tables that provide an overall summary of the present status of dome loads. Tables summarizing the load state corresponding to the soil depth and soil specific weight for the original qualification analysis, the gravity load requalification for soil depth and soil specific weight greater than the expected actual values, and a best estimate condition of soil depth and specific weight are presented for the Double-Shell Tanks. For the Single-Shell Tanks, only the original qualification analysis is available; thus, the tabulated results are for this case only. Section 6 provides a brief overview of past analysis and testing results that given an indication of the load capacity of the waste storage tanks that corresponds to a condition approaching ultimate failure of the tank. 31 refs

Wavefronts, light rays and caustic of a circular wave reflected by an arbitrary smooth curve

International Nuclear Information System (INIS)

Marciano-Melchor, Magdalena; Silva-Ortigoza, Ramón; Montiel-Piña, Enrique; Román-Hernández, Edwin; Santiago-Santiago, José Guadalupe; Silva-Ortigoza, Gilberto; Rosado, Alfonso; Suárez-Xique, Román

2011-01-01

The aim of the present work is to obtain expressions for both the wavefront train and the caustic associated with the light rays reflected by an arbitrary smooth curve after being emitted by a point light source located at an arbitrary position in the two-dimensional free space. To this end, we obtain an expression for the k-function associated with the general integral of Stavroudis to the eikonal equation that describes the evolution of the reflected light rays. The caustic is computed by using the definitions of the critical and caustic sets of the two-dimensional map that describes the evolution of an arbitrary wavefront associated with the general integral. The general results are applied to circular and parabolic mirrors. The main motivation to carry out this research is to establish, in future work, the caustic touching theorem in a two-dimensional optical medium and to study the diffraction problem by using the k-function concept. Both problems are important in the computation of the image of an arbitrary object under reflection and refraction

Appalachian mine soil morphology and properties: Effects of weathering and mining method

Energy Technology Data Exchange (ETDEWEB)

Haering, K.C.; Daniels, W.L.; Galbraith, J.M. [Virginia Polytechnic Institute & State University, Blacksburg, VA (United States)

2004-08-01

Surface coal mining and reclamation methods in the Appalachians have changed dramatically since the passage of the Surface Mining Control and Reclamation Act (SMCRA) of 1977 and subsequent improvements in mining and reclamation technology. In this study, 30 pre-SMCRA mine soil profiles (4-20 yr old) were examined and sampled in 1980 and compared with 20 mine soil profiles (8-13 yr old) described in the same area in 2002 after it had been completely remined by modern deep cut methods. Mine soils in both sampling years had high rock fragment content (42-81%), relatively well-developed A horizons, and generally exhibited A-C or A-AC-C horizonation. Although six Bw horizons were described in 1980, only two met all requirements for cambic horizons. The 1980 mine soils developed in overburden dominated by oxidized, preweathered material due to relatively shallow mining cuts. The 1980 mine soils had lower rock fragment content, finer textures, lower pH, and tended to be more heterogeneous in horizonation, morphology, and texture than soils observed in 2002, which had formed primarily in unweathered overburden from deeper cuts. Half the pedons sampled in both years had densic materials within 70 cm of the surface. Four poorly to very poorly drained soil profiles were described in each sampling year containing distinct hydric soil indicators in surface horizons. While older pre-SMCRA mine soils do have many properties in common with newer mine soils, their properties are highly influenced by the fact that they generally have formed in more weathered overburden from higher in the geologic column. Overall, Appalachian mine soils are much more complex in subsoil morphology than commonly assumed, and differential compaction greatly complicates their internal drainage and limits their overall productivity potential.

Novel Electrochemical Treatment of Spent Caustic from the Hydrocarbon Industry Using Ti/BDD

Directory of Open Access Journals (Sweden)

Alejandro Medel

2015-01-01

Full Text Available During the crude oil refining process, NaOH solutions are used to remove H2S, H2Saq, and sulfur compounds from different hydrocarbon streams. The residues obtained are called “spent caustics.” These residues can be mixed with those obtained in other processes, adding to its chemical composition naphthenic acids and phenolic compounds, resulting in one of the most dangerous industrial residues. In this study, the use of electrochemical technology (ET, using BDD with Ti as substrate (Ti/BDD, is evaluated in electrolysis of spent caustic mixtures, obtained through individual samples from different refineries. In this way, the Ti/BDD’s capability of carrying out the electrochemical destruction of spent caustics in an acidic medium is evaluated having as key process a chemical pretreatment phase. The potential production of •OHs, as the main reactive oxygen species electrogenerated over Ti/BDD surface, was evaluated in HCl and H2SO4 through fluorescence spectroscopy, demonstrating the reaction medium’s influence on its production. The results show that the hydrocarbon industry spent caustics can be mineralized to CO2 and water, driving the use of ET and of the Ti/BDD to solve a real problem, whose potential and negative impact on the environment and on human health is and has been the environmental agencies’ main focus.

K Basin Sludge Conditioning Process Testing Partitioning of PCBs in Dissolver Solution After Neutralization/Precipitation (Caustic Adjustment)

International Nuclear Information System (INIS)

Schmidt, A.J.; Thornton, B.M.; Hoppe, E.W.; Mong, G.M.; Silvers, K.L.; Slate, S.O.

1999-01-01

The purpose of the work described in this report was to gain a better understanding of how PCB congeners present in a simulated K Basin sludge dissolver solution will partition upon neutralization and precipitation (i.e., caustic adjustment). In a previous study (Mong et al. 1998),the entire series of sludge conditioning steps (acid dissolution, filtration, and caustic adjustment) were examined during integrated testing. In the work described here, the caustic adjustment step was isolated to examine the fate of PCBs in more detail within this processing step. For this testing, solutions of dissolver simulant (containing no solids) with a known initial concentration of PCB congeners were neutralized with caustic to generate a clarified supernatant and a settled sludge phase. PCBs were quantified in each phase (including the PCBs associated with the test vessel rinsates), and material balance information was collected

Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site.

Science.gov (United States)

Adama, M; Esena, R; Fosu-Mensah, B; Yirenya-Tawiah, D

2016-01-01

Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

Soil workability as a basis for advice on tillage activities

OpenAIRE

Cadena Zapata, M.

1999-01-01

In the tropical area of Mexico, when and how to carry out tillage is a qualitative decision. There is no quantified information about the interaction between a chosen process of cultivation, soil type and weather, which dictate the tool and power requirements. Waste of energy and soil degradation by erosion and compaction, and lack of timeliness are recognized problems caused by inadequate tillage management in the tropical area of Mexico.

In this thesis, the workab...

Erodibility of waste (Loess) soils from construction sites under water and wind erosional forces.

Science.gov (United States)

Tanner, Smadar; Katra, Itzhak; Argaman, Eli; Ben-Hur, Meni

2018-03-01

Excess soils from construction sites (waste soils) become a problem when exposed to soil erosion by water or wind. Understanding waste soil erodibility can contribute to its proper reuse for various surface applications. The general objective of the study was to provide a better understanding of the effects of soil properties on erodibility of waste soils excavated from various depths in a semiarid region under rainfall and wind erosive forces. Soil samples excavated from the topsoil (0-0.3m) and subsoil layers (0.3-0.9 and >1m depths) were subjected to simulated rainfall and wind. Under rainfall erosive forces, the subsoils were more erodible than the topsoil, in contrast to the results obtained under wind erosive forces. Exchangeable sodium percentage was the main factor controlling soil erodibility (K i ) under rainfall, and a significant logarithmic regression line was found between these two parameters. In addition, a significant, linear regression was found between K i and slaking values for the studied soil samples, suggesting that the former can be predicted from the latter. Soil erodibility under wind erosion force was controlled mainly by the dry aggregate characteristics (mean weight diameter and aggregate density): their higher values in the subsoil layers resulted in lower soil erodibility compared to the topsoil. Copyright © 2017 Elsevier B.V. All rights reserved.

Separation of technetium from nuclear waste stream simulants. Final report

International Nuclear Information System (INIS)

Strauss, S.H.

1995-01-01

The author studied liquid anion exchangers, such as Aliquat-336 nitrate, various pyridinium nitrates, and related salts, so that they may be applied toward a specific process for extracting (partitioning) and recovering 99 TcO 4 - from nuclear waste streams. Many of the waste streams are caustic and contain a variety of other ions. For this reason, the author studied waste stream simulants that are caustic and contain appropriate concentrations of selected, relevant ions. Methods of measuring the performance of the exchangers and extractant systems included contact experiments. Batch contact experiments were used to determine the forward and reverse extraction parameters as a function of temperature, contact time, phase ratio, concentration, solvent (diluent), and other physical properties. They were also used for stability and competition studies. Specifically, the author investigated the solvent extraction behavior of salts of perrhenate (ReO 4 - ), a stable (non-radioactive) chemical surrogate for 99 TcO 4 - . Results are discussed for alternate organic solvents; metalloporphyrins, ferrocenes, and N-cetyl pyridium nitrate as alternate extractant salts; electroactive polymers; and recovery of ReO 4 - and TcO 4 -

Final Report, University of California Merced: Uranium and strontium fate in waste-weathered sediments: Scaling of molecular processes to predict reactive transport (DE-SC0007095)

Energy Technology Data Exchange (ETDEWEB)

O' Day, Peggy Anne [University of California Merced; Chorover, Jon [University of Arizona; Steefel, Carl [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mueller, Karl [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-06-30

Objectives of the Project: 1. Determine the process coupling that occurs between mineral transformation and contaminant (U and Sr) speciation in acid-uranium waste weathered Hanford sediments. 2. Establish linkages between molecular-scale contaminant speciation and meso-scale contaminant lability, release and reactive transport. 3. Make conjunctive use of molecular- to bench-scale data to constrain the development of a mechanistic, reactive transport model that includes coupling of contaminant sorption-desorption and mineral transformation reactions. Hypotheses Tested: Uranium and strontium speciation in legacy sediments from the U-8 and U-12 Crib sites can be reproduced in bench-scale weathering experiments conducted on unimpacted Hanford sediments from the same formations; Reactive transport modeling of future uranium and strontium releases from the vadose zone of acid-waste weathered sediments can be effectively constrained by combining molecular-scale information on contaminant bonding environment with grain-scale information on contaminant phase partitioning, and meso-scale kinetic data on contaminant release from the waste-weathered porous media; Although field contamination and laboratory experiments differ in their diagenetic time scales (decades for field vs. months to years for lab), sediment dissolution, neophase nucleation, and crystal growth reactions that occur during the initial disequilibrium induced by waste-sediment interaction leave a strong imprint that persists over subsequent longer-term equilibration time scales and, therefore, give rise to long-term memory effects. Enabling Capabilities Developed: Our team developed an iterative measure-model approach that is broadly applicable to elucidate the mechanistic underpinnings of reactive contaminant transport in geomedia subject to active weathering.

IMAGE-PLANE ANALYSIS OF n-POINT-MASS LENS CRITICAL CURVES AND CAUSTICS

Energy Technology Data Exchange (ETDEWEB)

Danek, Kamil; Heyrovský, David, E-mail: kamil.danek@utf.mff.cuni.cz, E-mail: heyrovsky@utf.mff.cuni.cz [Institute of Theoretical Physics, Faculty of Mathematics and Physics, Charles University in Prague (Czech Republic)

2015-06-10

The interpretation of gravitational microlensing events caused by planetary systems or multiple stars is based on the n-point-mass lens model. The first planets detected by microlensing were well described by the two-point-mass model of a star with one planet. By the end of 2014, four events involving three-point-mass lenses had been announced. Two of the lenses were stars with two planetary companions each; two were binary stars with a planet orbiting one component. While the two-point-mass model is well understood, the same cannot be said for lenses with three or more components. Even the range of possible critical-curve topologies and caustic geometries of the three-point-mass lens remains unknown. In this paper we provide new tools for mapping the critical-curve topology and caustic cusp number in the parameter space of n-point-mass lenses. We perform our analysis in the image plane of the lens. We show that all contours of the Jacobian are critical curves of re-scaled versions of the lens configuration. Utilizing this property further, we introduce the cusp curve to identify cusp-image positions on all contours simultaneously. In order to track cusp-number changes in caustic metamorphoses, we define the morph curve, which pinpoints the positions of metamorphosis-point images along the cusp curve. We demonstrate the usage of both curves on simple two- and three-point-mass lens examples. For the three simplest caustic metamorphoses we illustrate the local structure of the image and source planes.

MINE WASTE TECHNOLOGY PROGRAM; PHOSPHATE STABILIZATION OF HEAVY METALS CONTAMINATED MINE WASTE YARD SOILS, JOPLIN, MISSOURI NPL SITE

Science.gov (United States)

This document summarizes the results of Mine Waste Technology Project 22-Phosphate Stabilization of Heavy Metals-Contaminated Mine Waste Yard Soils. Mining, milling, and smelting of ores near Joplin, Missouri, have resulted in heavy metal contamination of the area. The Joplin s...

Carbon speciation in ash, residual waste and contaminated soil by thermal and chemical analyses.

Science.gov (United States)

Kumpiene, Jurate; Robinson, Ryan; Brännvall, Evelina; Nordmark, Désirée; Bjurström, Henrik; Andreas, Lale; Lagerkvist, Anders; Ecke, Holger

2011-01-01

Carbon in waste can occur as inorganic (IC), organic (OC) and elemental carbon (EC) each having distinct chemical properties and possible environmental effects. In this study, carbon speciation was performed using thermogravimetric analysis (TGA), chemical degradation tests and the standard total organic carbon (TOC) measurement procedures in three types of waste materials (bottom ash, residual waste and contaminated soil). Over 50% of the total carbon (TC) in all studied materials (72% in ash and residual waste, and 59% in soil) was biologically non-reactive or EC as determined by thermogravimetric analyses. The speciation of TOC by chemical degradation also showed a presence of a non-degradable C fraction in all materials (60% of TOC in ash, 30% in residual waste and 13% in soil), though in smaller amounts than those determined by TGA. In principle, chemical degradation method can give an indication of the presence of potentially inert C in various waste materials, while TGA is a more precise technique for C speciation, given that waste-specific method adjustments are made. The standard TOC measurement yields exaggerated estimates of organic carbon and may therefore overestimate the potential environmental impacts (e.g. landfill gas generation) of waste materials in a landfill environment. Copyright © 2010 Elsevier Ltd. All rights reserved.

Factors inhibiting bioremediation of soil contaminated with weathered oils and drill cuttings

International Nuclear Information System (INIS)

Chaillan, F.; Chaineau, C.H.; Point, V.; Saliot, A.; Oudot, J.

2006-01-01

Oily drill cuttings and a soil contaminated with weathered crude oils were treated by enhanced biodegradation under tropical conditions in industrial scaled experiments. Oil contaminants were characterized by gas chromatography and mass spectrometry. This allowed for the identification of a mixture of two crude oils in the contaminated soil. After 12 months of bioremediation process, the removal of hydrocarbons reached by biodegradation an extent of 60% although nutrient amendment with elevated concentration of N-urea had highly detrimental effects on the hydrocarbon degrading fungal populations due to the production of toxic concentration of ammonia gas by nitrification. The saturated hydrocarbons were extensively assimilated, though n-alkanes were not completely removed. Aromatic hydrocarbons were less degraded than saturated whereas resin and asphaltene fractions were, surprisingly, partly assimilated. In laboratory conditions, the residual hydrocarbons in the field-treated materials were 15-20% further degraded when metabolic byproducts resulting from biodegradation were diluted or removed. - Bioremediation of oil-polluted soils can be impaired if urea is used as nitrogen source, and metabolic byproducts can limit biodegradation rates in industrial scaled experiments

Micaceous Soil Strength And Permeability Improvement Induced By Microbacteria From Vegetable Waste

Science.gov (United States)

Omar, R. C.; Roslan, R.; Baharuddin, I. N. Z.; Hanafiah, M. I. M.

2016-11-01

Green technology method using vegetable waste are introduced in this paper for improvement of phyllite residual soil from UNITEN, Campus. Residual soil from phyllite are known as micaceous soils and it give problem in managing the stability of the slope especially in wet and extensively dry seasons. Micaceous soil are collected using tube sampler technique and mixed with liquid contain microorganism from fermented vegetable waste name as vege-grout to form remolded sample. The remolded sample are classify as 15.0%, 17.5%, 20.00% and 22.5% based on different incremental percentages of vege-grout. The curing time for the sample are 7, 14, 21, 28, and 35 days before the tests were conducted. Observation of the effect of treatment shows 20.0% of liquid contain Bacillus pasteurii and Bacillus Subtilis with 21 days curing time is the optimum value in strengthening the soil and improve the permeability.

Using Resistivity Measurements to Determine Anisotropy in Soil and Weathered Rock

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S. Soto-Caban

2013-08-01

Full Text Available This study uses electrical resistivity measurements of soils and weathered rock to perform a fast and reliable evaluation of field anisotropy. Two test sites at New Concord, Ohio were used for the study. These sites are characterized by different landform and slightly east dipping limestone and siltstone formations of Pennsylvanian age. The measured resistivity ranged from 19 Ω∙m to 100 ��∙m, and varied with depth, landform, and season. The anisotropy was determined by a comparison of resistance values along the directions of strike and the dip. Measurements showed that the orientation of electrical anisotropy in the shallow ground may vary due to fluid connection, which is determined by the pore geometry in soil and rock, as well as by the direction of fluid movement. Results from this study indicated that a portable electrical resistivity meter is sensitive and reliable enough to be used for shallow ground fluid monitoring.

Soil warming for utilization and dissipation of waste heat from power generation in Pennsylvania

International Nuclear Information System (INIS)

DeWalle, D.R.

1977-01-01

The purpose of this paper is to describe the Penn State research project, which studies the soil warming by circulation of heated power plant discharge water through a buried pipe network. Waste heat can be utilized by soil warming for increased crop growth in open fields with proper selection of crops and cropping systems. Dissipation of waste heat from a buried pipe network can be predicted using either of two steady-state conduction equations tested. Accurate predictions are dependent upon estimates of the pipe outer-surface temperatures, soil surface temperatures in heated soil and soil thermal conductivity. The effect of economic optimization on soil-warming land area requirements for a 1500 MWe power plant in Pennsylvania is presented. (M.S.)

Design and implementation of a caustic flooding EOR pilot at Court Bakken heavy oil reservoir

Energy Technology Data Exchange (ETDEWEB)

Xie, J.; Chung, B.; Leung, L. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Nexen Inc., Calgary, AB (Canada)

2008-10-15

Successful waterflooding has been ongoing since 1988 at the Court Bakken heavy oil field in west central Saskatchewan. There are currently 20 injectors and 28 active oil producers in the Court main unit which is owned by Nexen and Pengrowth. The Court pool has an estimated 103.8 mmbbl of original oil in place (OOIP), of which 24 per cent has been successfully recovered after 20 years of waterflooding. A high-level enhanced oil recovery (EOR) screening study was conducted to evaluate other EOR technologies for a heavy oil reservoir of this viscosity range (17 degrees API). Laboratory studies showed that caustic flooding may enhance oil recovery after waterflooding at the Court Bakken heavy oil pool. A single well test demonstrated that caustic injection effectively reduced residual oil saturation. A sector model reservoir simulation revealed that caustic flood could achieve 9 per cent incremental oil recovery in the pilot area. Following the promising laboratory results, a successful caustic flood pilot was implemented at Court heavy oil pool where the major challenges encountered were low reservoir pressure and water channeling. 6 refs., 2 tabs., 6 figs.

Earthworm Comet Assay for Assessing the Risk of Weathered Petroleum Hydrocarbon Contaminated Soils: Need to Look Further than Target Contaminants.

Science.gov (United States)

Ramadass, Kavitha; Palanisami, Thavamani; Smith, Euan; Mayilswami, Srinithi; Megharaj, Mallavarapu; Naidu, Ravi

2016-11-01

Earthworm toxicity assays contribute to ecological risk assessment and consequently standard toxicological endpoints, such as mortality and reproduction, are regularly estimated. These endpoints are not enough to better understand the mechanism of toxic pollutants. We employed an additional endpoint in the earthworm Eisenia andrei to estimate the pollutant-induced stress. In this study, comet assay was used as an additional endpoint to evaluate the genotoxicity of weathered hydrocarbon contaminated soils containing 520 to 1450 mg hydrocarbons kg -1 soil. Results showed that significantly higher DNA damage levels (two to sixfold higher) in earthworms exposed to hydrocarbon impacted soils. Interestingly, hydrocarbons levels in the tested soils were well below site-specific screening guideline values. In order to explore the reasons for observed toxicity, the contaminated soils were leached with rainwater and subjected to earthworm tests, including the comet assay, which showed no DNA damage. Soluble hydrocarbon fractions were not found originally in the soils and hence no hydrocarbons leached out during soil leaching. The soil leachate's Electrical Conductivity (EC) decreased from an average of 1665 ± 147 to 204 ± 20 µS cm -1 . Decreased EC is due to the loss of sodium, magnesium, calcium, and sulphate. The leachate experiment demonstrated that elevated salinity might cause the toxicity and not the weathered hydrocarbons. Soil leaching removed the toxicity, which is substantiated by the comet assay and soil leachate analysis data. The implication is that earthworm comet assay can be included in future eco (geno) toxicology studies to assess accurately the risk of contaminated soils.

On the behaviour of test matter in the neighbourhood of caustics of homogeneous cosmological models

International Nuclear Information System (INIS)

Paul, H.G.

1983-01-01

Using power asymptotes for the metric of the BIANCHI types I, V, VII 0 , VIII and IX the intensity of geodesic focused scalar test matter is calculated in the neighbourhood of the caustic singularity of these space-time models. In all considered BIANCHI types there is a caustic diffraction with a diffraction field bounded by regions of extinction depending on the structure of the gravitational lense. (author)

Effects of biochar, waste water irrigation and fertilization on soil properties in West African urban agriculture.

Science.gov (United States)

Häring, Volker; Manka'abusi, Delphine; Akoto-Danso, Edmund K; Werner, Steffen; Atiah, Kofi; Steiner, Christoph; Lompo, Désiré J P; Adiku, Samuel; Buerkert, Andreas; Marschner, Bernd

2017-09-06

In large areas of sub-Saharan Africa crop production must cope with low soil fertility. To increase soil fertility, the application of biochar (charred biomass) has been suggested. In urban areas, untreated waste water is widely used for irrigation because it is a nutrient-rich year-round water source. Uncertainty exists regarding the interactions between soil properties, biochar, waste water and fertilization over time. The aims of this study were to determine these interactions in two typical sandy, soil organic carbon (SOC) and nutrient depleted soils under urban vegetable production in Tamale (Ghana) and Ouagadougou (Burkina Faso) over two years. The addition of biochar at 2 kg m -2 made from rice husks and corn cobs initially doubled SOC stocks but SOC losses of 35% occurred thereafter. Both biochar types had no effect on soil pH, phosphorous availability and effective cation exchange capacity (CEC) but rice husk biochar retained nitrogen (N). Irrigation with domestic waste water increased soil pH and exchangeable sodium over time. Inorganic fertilization alone acidified soils, increased available phosphorous and decreased base saturation. Organic fertilization increased SOC, N and CEC. The results from both locations demonstrate that the effects of biochar and waste water were less pronounced than reported elsewhere.

Time evolution of the general characteristics and Cu retention capacity in an acid soil amended with a bentonite winery waste.

Science.gov (United States)

Fernández-Calviño, David; Rodríguez-Salgado, Isabel; Pérez-Rodríguez, Paula; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel

2015-03-01

The effect of bentonite waste added to a "poor" soil on its general characteristic and copper adsorption capacity was assessed. The soil was amended with different bentonite waste concentrations (0, 10, 20, 40 and 80 Mg ha(-1)) in laboratory pots, and different times of incubation of samples were tested (one day and one, four and eight months). The addition of bentonite waste increased the pH, organic matter content and phosphorus and potassium concentrations in the soil, being stable for P and K, whereas the organic matter decreased with time. Additionally, the copper sorption capacity of the soil and the energy of the Cu bonds increased with bentonite waste additions. However, the use of this type of waste in soil presented important drawbacks for waste dosages higher than 20 Mg ha(-1), such as an excessive increase of the soil pH and an increase of copper in the soil solution. Copyright © 2014 Elsevier Ltd. All rights reserved.

Waste management of actinide contaminated soil

International Nuclear Information System (INIS)

Navratil, J.D.; Thompson, G.H.; Kochen, R.L.

1978-01-01

Waste management processes have been developed to reduce the volume of Rocky Flats soil contaminated with plutonium and americium and to prepare the contaminated fraction for terminal storage. The primary process consists of wet-screening. The secondary process uses attrition scrubbing and wet screening with additives. The tertiary process involves volume reduction of the contaminated fraction by calcination, or fixation by conversion to glass. The results of laboratory scale testing of the processes are described

Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

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M. Adama

2016-01-01

Full Text Available Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (Igeo and pollution load indices (PLI were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69, Pb (143.80, Cr (99.30, and Cd (7.54 in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites.

Heavy Metal Contamination of Soils around a Hospital Waste Incinerator Bottom Ash Dumps Site

Science.gov (United States)

Adama, M.; Esena, R.; Fosu-Mensah, B.; Yirenya-Tawiah, D.

2016-01-01

Waste incineration is the main waste management strategy used in treating hospital waste in many developing countries. However, the release of dioxins, POPs, and heavy metals in fly and bottom ash poses environmental and public health concerns. To determine heavy metal (Hg, Pb, Cd, Cr, and Ag) in levels in incinerator bottom ash and soils 100 m around the incinerator bottom ash dump site, ash samples and surrounding soil samples were collected at 20 m, 40 m, 60 m, 80 m, 100 m, and 1,200 m from incinerator. These were analyzed using the absorption spectrophotometer method. The geoaccumulation (I geo) and pollution load indices (PLI) were used to assess the level of heavy metal contamination of surrounding soils. The study revealed high concentrations in mg/kg for, Zn (16417.69), Pb (143.80), Cr (99.30), and Cd (7.54) in bottom ash and these were above allowable limits for disposal in landfill. The study also found soils within 60 m radius of the incinerator to be polluted with the metals. It is recommended that health care waste managers be educated on the implication of improper management of incinerator bottom ash and regulators monitor hospital waste incinerator sites. PMID:27034685

Heavy metals and organic compounds contamination in soil from an e-waste region in South China.

Science.gov (United States)

Liu, Ming; Huang, Bo; Bi, Xinhui; Ren, Zhaofang; Sheng, Guoying; Fu, Jiamo

2013-05-01

Heavy metals and persistent organic pollutants polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were analyzed in 34 surface soil samples collected from farmland and 7 soil or dust samples collected from the workshops in South China, where e-waste was dismantled using primitive techniques. The results show that Cd, Cu and Hg were the most abundant metals, in particular Cd pollution was serious in farmland soils, and the median concentrations in farmland soils were beyond the environmental quality standard for soils (China Grade II). A correlation between Cd, Cu, Zn, Pb and PCBs or PBDEs was significant indicating similar sources. Among the PCB congeners, high relative similarity was observed between the e-waste dump site soil (EW1) and Aroclor 1254, implying that the technical product Aroclor 1254 was one of the major sources of PCB contamination. High concentrations of PCBs in workshop dusts (D2 and D3) (1958 and 1675 μg kg(-1)) demonstrated that the workshops dismantling electrical wires and cables, electrical motors, compressors and aluminum apparatus containing PCBs in lubricants represent strong PCB emission sources to this area. Principal component analysis (PCA) and PBDE homologue patterns verify that farmland soils surrounding the e-waste recycling sites were enriched with lower brominated congeners, and the major source of PBDEs in dust samples might potentially be associated with the extensive use of deca-mix technical products as a flame retardant. The difference between e-waste soils, dusts and farmland soils can be observed in the PCA score plot of PCBs and PBDEs, and E-waste soils and dusts exhibited more diversity than farmland soils. Furthermore, a prediction of the particular kinds of pollution from different recycling activities through the analysis of each contamination and the connections between them was investigated.

Caustic-Side Solvent-Extraction Modeling for Hanford Interim Pretreatment System

International Nuclear Information System (INIS)

Moyer, B.A.; Birdwell, J.F.; Delmau, L. H.; McFarlane, J.

2008-01-01

The purpose of this work is to examine the applicability of the Caustic-Side Solvent Extraction (CSSX) process for the removal of cesium from Hanford tank-waste supernatant solutions in support of the Hanford Interim Pretreatment System (IPS). The Hanford waste types are more challenging than those at the Savannah River Site (SRS) in that they contain significantly higher levels of potassium, the chief competing ion in the extraction of cesium. It was confirmed by use of the CSSX model that the higher levels of potassium depress the cesium distribution ratio (DCs), as validated by measurement of DCs values for four of eight specified Hanford waste-simulant compositions. The model predictions were good to an apparent standard error of ±11%. It is concluded from batch distribution experiments, physical-property measurements, equilibrium modeling, flowsheet calculations, and contactor sizing that the CSSX process as currently employed for cesium removal from alkaline salt waste at the SRS is capable of treating similar Hanford tank feeds. For the most challenging waste composition, 41 stages would be required to provide a cesium decontamination factor (DF) of 5000 and a concentration factor (CF) of 5. Commercial contacting equipment with rotor diameters of 10 in. for extraction and 5 in. for stripping should have the capacity to meet throughput requirements, but testing will be required to confirm that the needed efficiency and hydraulic performance are actually obtainable. Markedly improved flowsheet performance was calculated for a new solvent formulation employing the more soluble cesium extractant BEHBCalixC6 used with alternative scrub and strip solutions, respectively 0.1 M NaOH and 10 mM boric acid. The improved system can meet minimum requirements (DF = 5000 and CF = 5) with 17 stages or more ambitious goals (DF = 40,000 and CF = 15) with 19 stages. Potential benefits of further research and development are identified that would lead to reduced costs, greater

Mill Integration-Pulping, Stream Reforming and Direct Causticization for Black Liquor Recovery

Energy Technology Data Exchange (ETDEWEB)

Adriaan van Heiningen

2007-06-30

MTCI/StoneChem developed a steam reforming, fluidized bed gasification technology for biomass. DOE supported the demonstration of this technology for gasification of spent wood pulping liquor (or 'black liquor') at Georgia-Pacific's Big Island, Virginia mill. The present pre-commercial R&D project addressed the opportunities as well as identified negative aspects when the MTCI/StoneChem gasification technology is integrated in a pulp mill production facility. The opportunities arise because black liquor gasification produces sulfur (as H{sub 2}S) and sodium (as Na{sub 2}CO{sub 3}) in separate streams which may be used beneficially for improved pulp yield and properties. The negative aspect of kraft black liquor gasification is that the amount of Na{sub 2}CO{sub 3} which must be converted to NaOH (the so called causticizing requirement) is increased. This arises because sulfur is released as Na{sub 2}S during conventional kraft black liquor recovery, while during gasification the sodium associated Na{sub 2}S is partly or fully converted to Na{sub 2}CO{sub 3}. The causticizing requirement can be eliminated by including a TiO{sub 2} based cyclic process called direct causticization. In this process black liquor is gasified in the presence of (low sodium content) titanates which convert Na{sub 2}CO{sub 3} to (high sodium content) titanates. NaOH is formed when contacting the latter titanates with water, thereby eliminating the causticizing requirement entirely. The leached and low sodium titanates are returned to the gasification process. The project team comprised the University of Maine (UM), North Carolina State University (NCSU) and MTCI/ThermoChem. NCSU and MTCI are subcontractors to UM. The principal organization for the contract is UM. NCSU investigated the techno-economics of using advanced pulping techniques which fully utilize the unique cooking liquors produced by steam reforming of black liquor (Task 1). UM studied the kinetics and

The influence of rice husk and tobacco waste biochars on soil quality

Directory of Open Access Journals (Sweden)

Amir Hamzah

2017-10-01

Full Text Available Heavy metal pollution in agricultural land threatens soil and food quality. Soil pollution could be remediate using biochar, but the effectiveness of biochar on soil quality improvement is determined by types of feedstock and pyrolysis temperature. This study was aimed to explore the effect of different types of biochar on soil properties.  Biochar from rice husk and tobacco waste was applied to soil contaminated with lead and mercury. This study was conducted at Sumber Brantas, Malang East Java, and used a completely randomized design with three replicates. Heavy metals content was measured using AAS. The results of measurements were analyzed using analysis of variance at 5% and 1% significance levels. The initial analysis of the soil properties at the research site showed that the soil nutrient status was low, i.e. N (0.2 %, K (0.50 cmol+/kg, and CEC (5.9 me/100g respectively, but soil pH was neutral (6.8. The research site also has crossed the threshold of heavy metal content for Hg (0.5 ppm, Pb (25.22 ppm, Cd (1.96 ppm, and As (0.78 ppm. Biochar added had a positive influence on soil characteristics improvement. It could increase the content of organic C, i.e. 35.12% and 31.81% and CEC (cation exchange capacity, i.e.30.56 me/100g and 28.13 me/100 g for rice husk biochar and tobacco waste biochar, respectively.  However, N, P, and K contents were low i.e. N ( 0.33 and 0.30 %; P2O5 (148.79 and 152 ppm; K (1.58 and 2.11 mg/100g for rice husk biochar and tobacco waste biochar, respectively.

Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

International Nuclear Information System (INIS)

Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J.; Goethals, L.; Springael, D.

2005-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J. [Flemish Institute for Technological Research-Vito, Mol (Belgium); Goethals, L. [ENVISAN, Aalst, (Belgium); Springael, D. [Catholic University of Leuven-KUL, Leuven (Belgium)

2005-07-01

Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

Gravitational microlensing - Powerful combination of ray-shooting and parametric representation of caustics

Science.gov (United States)

Wambsganss, J.; Witt, H. J.; Schneider, P.

1992-01-01

We present a combination of two very different methods for numerically calculating the effects of gravitational microlensing: the backward-ray-tracing that results in two-dimensional magnification patterns, and the parametric representation of caustic lines; they are in a way complementary to each other. The combination of these methods is much more powerful than the sum of its parts. It allows to determine the total magnification and the number of microimages as a function of source position. The mean number of microimages is calculated analytically and compared to the numerical results. The peaks in the lightcurves, as obtained from one-dimensional tracks through the magnification pattern, can now be divided into two groups: those which correspond to a source crossing a caustic, and those which are due to sources passing outside cusps. We determine the frequencies of those two types of events as a function of the surface mass density, and the probability distributions of their magnitudes. We find that for low surface mass density as many as 40 percent of all events in a lightcurve are not due to caustic crossings, but rather due to passings outside cusps.

Investigation of soils affected by burnt hospital wastes in Nigeria using PIXE.

Science.gov (United States)

Ephraim P, Inyang; Ita, Akpan; Eusebius I, Obiajunwa

2013-12-01

Improper management of hospital waste has been reported to be responsible for several acute outbreaks like the severe acute respiratory syndrome (SARS). In spite of these challenges, hospital wastes are sometimes not properly handled in Nigeria. To date, there has not been an adequate study on the effect and fate of burnt hospital waste on agricultural soil. The effect of burnt hospital wastes on the agricultural soil was conducted on soils sampled around farm settlement near Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, South West Nigeria. PIXE technique was employed with a 1.7 MV 5SDH Tandem Pelletron accelerator available at Centre for Energy Research and Development O.A.U Ile-Ife, Nigeria. Eleven elements- Si, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Zr and Pb were detected and their concentrations and enrichment factors determined. The presence of Pb and Cl at the elevated concentrations range of (77.8 ± 3.5 - 279.6 ± 97.6 and 102.2 ± 37.4 -167.2±17.43) ppm respectively in this study, is of serious health concern because of the agricultural practices in the neighborhoods of the study sites. There is a need for proper handling of hospital and other related hazardous wastes because of the possibility of such posing serious environmental pollution problems.

Prediction of stress-strain state of municipal solid waste with application of soft soil creep model

Directory of Open Access Journals (Sweden)

Ofrikhter Vadim Grigor'evich

Full Text Available The deformation of municipal solid waste is a complex process caused by the nature of MSW, the properties of which differ from the properties of common soils. The mass of municipal solid waste shows the mixed behaviour partially similar to granular soils, and partially - to cohesive. So, one of mechanical characteristics of MSW is the cohesion typical to cohesive soils, but at the same time the filtration coefficient of MSW has an order of 1 m/day that is characteristic for granular soils. It has been established that MSW massif can be simulated like the soil reinforced by randomly oriented fibers. Today a significant amount of the verified and well proved software products are available for numerical modelling of soils. The majority of them use finite element method (FEM. The soft soil creep model (SSC-model seems to be the most suitable for modelling of municipal solid waste, as it allows estimating the development of settlements in time with separation of primary and secondary consolidation. Unlike the soft soil, one of the factors of secondary consolidation of MSW is biological degradation, the influence of which is possible to consider at the definition of the modified parameters essential for soft soil model. Application of soft soil creep model allows carrying out the calculation of stress-strain state of waste from the beginning of landfill filling up to any moment of time both during the period of operation and in postclosure period. The comparative calculation presented in the paper is executed in Plaxis software using the soft-soil creep model in contrast to the calculation using the composite model of MSW. All the characteristics for SSC-model were derived from the composite model. The comparative results demonstrate the advantage of SSC-model for prediction of the development of MSW stress-strain state. As far as after the completion of the biodegradation processes MSW behaviour is similar to cohesion-like soils, the demonstrated

Risk of Leaching in Soils Amended by Compost and Digestate from Municipal Solid Waste

Science.gov (United States)

Tarquis, Ana M.; Cartagena, M. Carmen

2014-01-01

New European directives have proposed the direct application of compost and digestate produced from municipal solid wastes as organic matter sources in agricultural soils. Therefore information about phosphorus leaching from these residues when they are applied to the soil is increasingly important. Leaching experiments were conducted to determine the P mobility in compost and digestate mixtures, supplying equivalent amounts to 100 kg P ha−1 to three different types of soils. The tests were performed in accordance with CEN/TS 14405:2004 analyzing the maximum dissolved reactive P and the kinetic rate in the leachate. P biowaste fractionation indicated that digestate has a higher level of available P than compost has. In contrast, P losses in leaching experiments with soil-compost mixtures were higher than in soil-digestate mixtures. For both wastes, there was no correlation between dissolved reactive P lost and the water soluble P. The interaction between soil and biowaste, the long experimentation time, and the volume of leachate obtained caused the waste's wettability to become an influential parameter in P leaching behavior. The overall conclusion is that kinetic data analysis provides valuable information concerning the sorption mechanism that can be used for predicting the large-scale behavior of soil systems. PMID:25003139

Ecological effects of combined pollution associated with e-waste recycling on the composition and diversity of soil microbial communities.

Science.gov (United States)

Liu, Jun; He, Xiao-Xin; Lin, Xue-Rui; Chen, Wen-Ce; Zhou, Qi-Xing; Shu, Wen-Sheng; Huang, Li-Nan

2015-06-02

The crude processing of electronic waste (e-waste) has led to serious contamination in soils. While microorganisms may play a key role in remediation of the contaminated soils, the ecological effects of combined pollution (heavy metals, polychlorinated biphenyls, and polybrominated diphenyl ethers) on the composition and diversity of microbial communities remain unknown. In this study, a suite of e-waste contaminated soils were collected from Guiyu, China, and the indigenous microbial assemblages were profiled by 16S rRNA high-throughput sequencing and clone library analysis. Our data revealed significant differences in microbial taxonomic composition between the contaminated and the reference soils, with Proteobacteria, Acidobacteria, Bacteroidetes, and Firmicutes dominating the e-waste-affected communities. Genera previously identified as organic pollutants-degrading bacteria, such as Acinetobacter, Pseudomonas, and Alcanivorax, were frequently detected. Canonical correspondence analysis revealed that approximately 70% of the observed variation in microbial assemblages in the contaminated soils was explained by eight environmental variables (including soil physiochemical parameters and organic pollutants) together, among which moisture content, decabromodiphenyl ether (BDE-209), and copper were the major factors. These results provide the first detailed phylogenetic look at the microbial communities in e-waste contaminated soils, demonstrating that the complex combined pollution resulting from improper e-waste recycling may significantly alter soil microbiota.

P-Area Acid/Caustic Basin groundwater monitoring report. First quarter 1995

International Nuclear Information System (INIS)

Chase, J.A.

1995-06-01

During first quarter 1995, groundwater from the six PAC monitoring wells at the P-Area Acid/Caustic Basin was analyzed for herbicides/pesticides, indicator parameters, metals, nitrate, adionuclide indicators, and other constituents. Monitoring results that exceeded the final Primary Drinking Water Standards (PDWS) or the Savannah River Site (SRS) flagging criteria or turbidity standard during the quarter are discussed in this report. During first quarter 1995, no constituents exceeded the final PDWS. Aluminum exceeded its SRS Flag 2 criterion in all six PAC wells. Iron and manganese exceeded Flag 2 criteria in three wells, while turbidity was elevated in one well. Groundwater flow direction and rate in the water table beneath the P-Area Acid/Caustic Basin were similar to past quarters

Weathering processes in waste materials from a mining area in a semiarid zone

International Nuclear Information System (INIS)

Navarro-Hervás, Cortes; Pérez-Sirvent, Carmen; Martínez-Sánchez, María José; García-Lorenzo, Mari Luz; Molina, José

2012-01-01

Chemical and mineralogical characterization of waste materials present in an abandoned Pb, Zn–Ag mining site (SE, Spain) was carried out. In unaltered rocks, the mineralogy is characterized by plagioclase, pyroxene, magnetite, ilmenite, amphibole, biotite and quartz. Trace-element contents of these samples represent unaltered values. In mine-waste materials, pH ranged from acidic to slightly acidic and trace-element content was generally high, especially for Pb and Zn, although there were also substantial As concentrations. X-ray diffraction results suggested that these samples have a complex mineralogy, including alteration products. Surficial materials in the study area were affected by weathering processes, generating supergene assemblages, including Fe and Mn oxides and hydroxides, carbonates, hydrated sulfates and jarosite. Knowledge of the geochemical processes that took place in the past and which are still taking place provide an important tool for assessing associated environmental problems in this area.

Effect of soil-rock system on speleothems weathering in Bailong Cave, Yunnan Province, China*

Science.gov (United States)

Wang, Jing; Song, Lin-hua

2005-01-01

Bailong Cave with its well-developed Middle Triassic calcareous dolomite’s system was opened as a show cave for visitors in 1988. The speleothem scenery has been strongly weathered as white powder on the outer layers. Study of the cave winds, permeability of soil-rock system and the chemical compositions of the dripping water indicated: (1) The cave dimension structure distinctively affects the cave winds, which were stronger at narrow places. (2) Based on the different soil grain size distribution, clay was the highest in composition in the soil. The response sense of dripping water to the rainwater percolation was slow. The density of joints and other openings in dolomite make the dolomite as mesh seepage body forming piles of thin and high columns and stalactites. (3) Study of 9 dripping water samples by HYDROWIN computer program showed that the major mineral in the water was dolomite. PMID:15682505

Phyllosilicate weathering pathways in chlorite-talc bearing soil parent materials, D.R. Congo: early findings.

Science.gov (United States)

Dumon, Mathijs; Oostermeyer, Fran; Timmermans, Els; De Meulemeester, Aschwin; Mees, Florias; Van Driessche, Isabel; Erens, Hans; Bazirake Mujinya, Basile; Van Ranst, Eric

2015-04-01

The study of the formation and transformation of clay minerals is of the upmost importance to understand soil formation and to adjust land-use management to the land surface conditions. These clay minerals determine to a large extent the soil physical and chemical properties. It is commonly observed that over time the mineralogy of any parent material is transformed to a simple assemblage composed mostly of Al and Fe oxides and low-activity clays, e.g. kaolinite. This is especially obvious in the humid tropics, which have been protected from glacial erosion, allowing deep, highly weathered soils to form. Despite the abundant presence of kaolinite in these soils, its formation pathways are still under debate: either neoformation by dissolution-crystallisation reactions or solid-state transformation of 2:1 phyllosilicates. To elucidate this, weathering sequences in a unique 40 m core taken below a termite mound, reaching a talc-chlorite bearing substrate in the Lubumbashi area, Katanga, DR Congo are being investigated in detail using a.o. quantitative X-ray diffraction analysis, chemical characterization, micromorphology and µXRF-scanning with the main objective to improve the understanding of the formation pathways of kaolinite subgroup minerals in humid tropical environments. Based on an initial characterization of the core, two zones of interest were selected for more detailed analysis, for which the early findings will be presented. The first zone extends from ca. 9 m to 11 m below the surface is dominated by kaolinite but shows early traces of primary talc and micas. The second zone extends from 34 to 36 m below the surface and contains large amounts of chlorite, with smaller amounts of talc, micas and kaolinite.

Spatial variability in mycorrhizal hyphae and nutrient and water availability in a soil-weathered bedrock profile

Science.gov (United States)

L.M. Egerton-Warburton; R.C. Graham; K.R. Hubbert

2003-01-01

We documented the spatial distribution, abundance and molecular diversity of mycorrhizal hyphae and physical and chemical properties of soil-weathered bedrock in a chaparral community that experiences seasonal drought. Because plants in this community were known to rely on bedrock-stored water during the summer, the data were used to evaluate the potential role of...

Impact of pulp and paper mill effluents and solid wastes on soil mineralogical and physicochemical properties.

Science.gov (United States)

Adhikari, Gopi; Bhattacharyya, Krishna G

2015-03-01

The present study was carried out to evaluate the impact of the effluents and the solid wastes generated by a giant pulp and paper mill in the northeastern part of India on soil mineralogy of the area. The impacts were monitored by analysis of soil samples from seven sites located in the potential impact zone and a control site where any kind of effluent discharge or solid waste dumping was absent. The soil belonged to medium texture type (sandy clay loam, sandy loam, loamy sand, and silt loam), and the soil aggregate analysis indicated higher levels of organic carbon, pH, electrical conductivity, effective cation exchange capacity, and mean weight diameter at sites receiving effluents and solid wastes from the pulp and paper mill. Depletion in soil silica level and in feldspar and quartz contents and rise in iron and calcium contents at the sites receiving effluents from the pulp and paper mill indicated significant influence on soil mineralogy. The soil contained a mixture of minerals consisting of tectosilicates (with silicate frameworks as in quartz or feldspar), phylosilicates (layered clays like kaolinite, smectite, chlorite, illite, etc.), and carbonates. Absence of pure clay minerals indicated a state of heterogeneous intermediate soil clay transformation. The significance of the mixed mineralogy in relation to the disposal of effluents and dumping of solid wastes is discussed in details.

Unmodified versus caustics-impregnated carbons for control of hydrogen sulfide emissions from sewage treatment plants

Energy Technology Data Exchange (ETDEWEB)

Bandosz, T.J.; Bagreev, A.; Adib, F.; Turk, A.

2000-03-15

Unmodified and caustic-impregnated carbons were compared as adsorbents for hydrogen sulfide in the North River Water Pollution Control Plant in New York City over a period of 2 years. The carbons were characterized using accelerated H{sub 2}S breakthrough capacity tests, sorption of nitrogen, potentiometric titration, and thermal analysis. The accelerated laboratory tests indicate that the initial capacity of caustic-impregnated carbons exceeds that of unmodified carbon, but the nature of real-life challenge streams, particularly their lower H{sub 2}S concentrations, nullifies this advantage. As the caustic content of the impregnated carbon is consumed, the situation reverses, and the unmodified carbon becomes more effective. When the concentration of H{sub 2}S is low, the developed surface area and pore volume along with the affinity to retain water create a favorable environment for dissociative adsorption of hydrogen sulfide and its oxidation to elemental sulfur, S{sup 4+}, and S{sup 6+}. In the case of the caustic carbon, the catalytic impact of the carbon surface is limited, and its good performance lasts only while active base is present. The results also show the significant differences in performance of unmodified carbons due to combined effects of their porosity and surface chemistry.

Changes in soil hydraulic properties caused by construction of a simulated waste trench at the Idaho National Engineering Laboratory, Idaho

International Nuclear Information System (INIS)

Shakofsky, S.

1995-03-01

In order to assess the effect of filled waste disposal trenches on transport-governing soil properties, comparisons were made between profiles of undisturbed soil and disturbed soil in a simulated waste trench. The changes in soil properties induced by the construction of a simulated waste trench were measured near the Radioactive Waste Management Complex at the Idaho National Engineering Laboratory (INEL) in the semiarid southeast region of Idaho. The soil samples were collected, using a hydraulically-driven sampler to minimize sample disruption, from both a simulated waste trench and an undisturbed area nearby. Results show that the undisturbed profile has distinct layers whose properties differ significantly, whereas the soil profile in the simulated waste trench is, by comparison, homogeneous. Porosity was increased in the disturbed cores, and, correspondingly, saturated hydraulic conductivities were on average three times higher. With higher soil-moisture contents (greater than 0.32), unsaturated hydraulic conductivities for the undisturbed cores were typically greater than those for the disturbed cores. With lower moisture contents, most of the disturbed cores had greater hydraulic conductivities. The observed differences in hydraulic conductivities are interpreted and discussed as changes in the soil pore geometry

Oxygen influx and geochemistry of percolate water from reactive mine waste rock underlying a sloping channelled soil cover

Energy Technology Data Exchange (ETDEWEB)

Song Qing, E-mail: qsong3@uwo.ca [Geotechnical Research Center, Department of Civil and Environmental Engineering, University of Western Ontario, 1151 Richmond Street, London, ON, N6A 5B9 (Canada); Yanful, Ernest K., E-mail: eyanful@eng.uwo.ca [Geotechnical Research Center, Department of Civil and Environmental Engineering, University of Western Ontario, 1151 Richmond Street, London, ON, N6A 5B9 (Canada)

2011-05-15

Research Highlights: > A channelled cover with preferential flow can still mitigate ARD to some extent. > Oxygen ingress was more sensitive to the location of the channel than to K{sub s}. > The channel in the barrier layer was a major passage for O{sub 2} ingress. > Actual flushing was an important factor when estimating O{sub 2} decay coefficient. - Abstract: An ideal engineered soil cover can mitigate acid rock drainage (ARD) by limiting water and gaseous O{sub 2} ingress into an underlying waste rock pile. However, the barrier layer in the soil cover almost invariably tends to develop cracks or fractures after placement. These cracks may change water flow and O{sub 2} transport in the soil cover and decrease performance in the long run. The present study employed a 10-cm-wide sand-filled channel installed in a soil barrier layer (silty clay) to model the aggregate of cracks or fractures that may be present in the cover. The soil cover had a slope of 20%. Oxygen transport through the soil cover and oxidation of the underlying waste rock were investigated and compared to a controlled column test with bare waste rock (without soil cover). Moreover, gaseous O{sub 2} transport in the soil cover with channel and its sensitivity to channel location as well as the influence of the saturated hydraulic conductivity of the channel material were modeled using the commercial software VADOSE/W. The results indicted that the waste rock underlying the soil cover with channel had a lower oxidation rate than the waste rock without cover because of reduced O{sub 2} ingress and water flushing in the soil cover with channel, which meant a partial soil cover might still be effective to some extent in reducing ARD generation. Gaseous O{sub 2} ingress into the covered waste rock was more sensitive to the channel location than to the saturated hydraulic conductivity of the material filling the channel. Aqueous equilibrium speciation modeling and scanning electron microscopy with energy

Recycling soil nitrate nitrogen by amending agricultural lands with oily food waste.

Science.gov (United States)

Rashid, M T; Voroney, R P

2003-01-01

With current agricultural practices the amounts of fertilizer N applied are frequently more than the amounts removed by the crop. Excessive N application may result in short-term accumulation of nitrate nitrogen (NO3-N) in soil, which can easily be leached from the root zone and into the ground water. A management practice suggested for conserving accumulated NO3-N is the application of oily food waste (FOG; fat + oil + greases) to agricultural soils. A two-year field study (1995-1996 and 1996-1997) was conducted at Elora Research Center (43 degrees 38' N, 80 degrees W; 346 m above mean sea level), University of Guelph, Ontario, Canada to determine the effect of FOG application in fall and spring on soil NO3-N contents and apparent N immobilization-mineralization of soil N in the 0- to 60-cm soil layer. The experiment was planned under a randomized complete block design with four replications. An unamended control and a reference treatment [winter wheat (Triticum aestivum L.) cover crop] were included in the experiment to compare the effects of fall and spring treatment of oily food waste on soil NO3-N contents and apparent N immobilization-mineralization. Oily food waste application at 10 Mg ha(-1) in the fall decreased soil NO3-N by immobilization and conserved 47 to 56 kg NO3-N ha(-1), which would otherwise be subject to leaching. Nitrogen immobilized due to FOG application in the fall was subsequently remineralized by the time of fertilizer N sidedress, whereas no net mineralization was observed in spring-amended plots at the same time.

Next Generation Solvent Performance in the Modular Caustic Side Solvent Extraction Process - 15495

Energy Technology Data Exchange (ETDEWEB)

Smith, Tara E. [Savannah River Remediation, LLC., Aiken, SC (United States); Scherman, Carl [Savannah River Remediation, LLC., Aiken, SC (United States); Martin, David [Savannah River Remediation, LLC., Aiken, SC (United States); Suggs, Patricia [Savannah River Site (SRS), Aiken, SC (United States)

2015-01-14

Changes to the Modular Caustic Side Solvent Extraction Unit (MCU) flow-sheet were implemented in the facility. Implementation included changing the scrub and strip chemicals and concentrations, modifying the O/A ratios for the strip, scrub, and extraction contactor banks, and blending the current BoBCalixC6 extractant-based solvent in MCU with clean MaxCalix extractant-based solvent. During the successful demonstration period, the MCU process was subject to rigorous oversight to ensure hydraulic stability and chemical/radionuclide analysis of the key process tanks (caustic wash tank, solvent hold tank, strip effluent hold tank, and decontaminated salt solution hold tank) to evaluate solvent carryover to downstream facilities and the effectiveness of cesium removal from the liquid salt waste. Results indicated the extraction of cesium was significantly more effective with an average Decontamination Factor (DF) of 1,129 (range was 107 to 1,824) and that stripping was effective. The contactor hydraulic performance was stable and satisfactory, as indicated by contactor vibration, contactor rotational speed, and flow stability; all of which remained at or near target values. Furthermore, the Solvent Hold Tank (SHT) level and specific gravity was as expected, indicating that solvent integrity and organic hydraulic stability were maintained. The coalescer performances were in the range of processing results under the BOBCalixC6 flow sheet, indicating negligible adverse impact of NGS deployment. After the Demonstration period, MCU began processing via routine operations. Results to date reiterate the enhanced cesium extraction and stripping capability of the Next Generation Solvent (NGS) flow sheet. This paper presents process performance results of the NGS Demonstration and continued operations of MCU utilizing the blended BobCalixC6-MaxCalix solvent under the NGS flowsheet.

Caustic Ingestion in the Elderly: Influence of Age on Clinical Outcome

Directory of Open Access Journals (Sweden)

Blazena Caganova

2017-10-01

Full Text Available Caustic poisonings are still associated with many fatalities. Studies focusing on the elderly are rare. The purpose of the present study was to compare the clinical outcomes of caustic ingestion injury in elderly and non-elderly adults with regard to gender, intent of exposure, substance ingested, severity of mucosal injury, complications, and mortality. Caustic substance exposures reported to the National Toxicological Information Centre in Slovakia during 1998–2015 were reviewed retrospectively. The patients were divided into two groups: the non-elderly (<60 years and elderly adults (≥60 years. The mortality rate in the elderly was significantly higher (elderly 23.0% vs. non-elderly 11.3%; p = 0.041. The risk of fatal outcome in the elderly was increased by acid ingestion (OR = 7.822; p = 0.002, particularly hydrochloric acid (OR = 5.714, p = 0.006. The incidence of respiratory complications was almost two times higher in the elderly was 31.1% vs. 17.4% for the non-elderly (p = 0.037. Respiratory complications significantly correlated with an increased mortality rate (p = 0.001 in the elderly whereas there was no association between GI complications and mortality in the elderly (p = 0.480. Elderly patients with respiratory complications had the poorest clinical outcomes. The highest risk of complications and fatalities was observed in patients after hydrochloric acid ingestion.

Effect of waste synthetic bag pieces on the CBR value of expansive Soil

Directory of Open Access Journals (Sweden)

Ajay Kumar Agarwal

2015-03-01

Full Text Available Expansive soils such as black cotton soil which are widely distributed in India have a tendency for volume changes due to change in moisture content. Also exhibits very low bearing capacity and high compressibility. Stabilization of such soil by admixture is used commonly now days. But no mix is suitable to improve all the types of soil. But it is obvious that depending on type of soil & type of admixture the optimum mix can be designed.  In this paper a mix has been designed to improve the bearing capacity of soil by using fly ash and lime mixture, reinforced with waste synthetic bag pieces. Various tests are carried out to determine the CBR value and other soil properties with and without using any admixture and reinforcement. The maximum value of CBR was found to be23.82% for 2.5 mm penetration and 22.21% for 5 mm penetration, when waste synthetic bag pieces of size 2 cm * 2 cm were used at a proportion of 0.1%.

Pollution distribution of heavy metals in surface soil at an informal electronic-waste recycling site.

Science.gov (United States)

Fujimori, Takashi; Takigami, Hidetaka

2014-02-01

We studied distribution of heavy metals [lead (Pb), copper (Cu) and zinc (Zn)] in surface soil at an electronic-waste (e-waste) recycling workshop near Metro Manila in the Philippines to evaluate the pollution size (spot size, small area or the entire workshop), as well as to assess heavy metal transport into the surrounding soil environment. On-site length-of-stride-scale (~70 cm) measurements were performed at each surface soil point using field-portable X-ray fluorescence (FP-XRF). The surface soil at the e-waste recycling workshop was polluted with Cu, Zn and Pb, which were distributed discretely in surface soil. The site was divided into five areas based on the distance from an entrance gate (y-axis) of the e-waste recycling workshop. The three heavy metals showed similar concentration gradients in the y-axis direction. Zn, Pb and Cu concentrations were estimated to decrease to half of their maximum concentrations at ~3, 7 and 7 m from the pollution spot, respectively, inside the informal e-waste recycling workshop. Distance from an entrance may play an important role in heavy metal transport at the soil surface. Using on-site FP-XRF, we evaluated the metal ratio to characterise pollution features of the solid surface. Variability analysis of heavy metals revealed vanishing surficial autocorrelation over metre ranges. Also, the possibility of concentration prediction at unmeasured points using geostatistical kriging was evaluated, and heavy metals had a relative "small" pollution scales and remained inside the original workshop compared with toxic organohalogen compounds. Thus, exposure to heavy metals may directly influence the health of e-waste workers at the original site rather than the surrounding habitat and environmental media.

Ecological risk assessment of organic waste amendments using the species sensitivity distribution from a soil organisms test battery

International Nuclear Information System (INIS)

Domene, Xavier; Ramirez, Wilson; Mattana, Stefania; Alcaniz, Josep Maria; Andres, Pilar

2008-01-01

Safe amendment rates (the predicted no-effect concentration or PNEC) of seven organic wastes were estimated from the species sensitivity distribution of a battery of soil biota tests and compared with different realistic amendment scenarios (different predicted environmental concentrations or PEC). None of the wastes was expected to exert noxious effects on soil biota if applied according either to the usual maximum amendment rates in Europe or phosphorus demands of crops (below 2 tonnes DM ha -1 ). However, some of the wastes might be problematic if applied according to nitrogen demands of crops (above 2 tonnes DM ha -1 ). Ammonium content and organic matter stability of the studied wastes are the most influential determinants of the maximum amendment rates derived in this study, but not pollutant burden. This finding indicates the need to stabilize wastes prior to their reuse in soils in order to avoid short-term impacts on soil communities. - Ecological risk assessment of organic waste amendments

Coupling of physical erosion and chemical weathering after phases of intense human activity

Science.gov (United States)

Schoonejans, Jerome; Vanacker, Veerle; Opfergelt, Sophie; Ameijeiras-Mariño, Yolanda; Kubik, Peter W.

2014-05-01

Anthropogenic disturbance of natural vegetation profoundly alters the lateral and vertical fluxes of soil nutrients and particles at the land surface. Human-induced acceleration of soil erosion can thereby result in an imbalance between physical erosion, soil production and chemical weathering. The (de-)coupling between physical erosion and chemical weathering in ecosystems with strong anthropogenic disturbances is not yet fully understood, as earlier studies mostly focused on natural ecosystems. In this study, we explore the chemical weathering intensity for four study sites located in the Internal Zone of the Spanish Betic Cordillera. Most of the sites belong to the Nevado-Filabres complex, but are characterized by different rates of long-term exhumation, 10Be catchment-wide denudation and hill slope morphology. Denudation rates are generally low, but show large variation between the three sites (from 23 to 246 mm kyr-1). The magnitude of denudation rates is consistent with longer-term uplift rates derived from marine deposits, fission-track measurements and vertical fault slip rates. Two to three soil profiles were sampled per study site at exposed ridge tops. All soils overly fractured mica schist, and are very thin (< 60cm). In each soil profile, we sampled 5 depth slices, rock fragments and the (weathered) bedrock. In total, 38 soil and 20 rock samples were analyzed for their chemical composition. The chemical weathering intensity is constrained by the Chemical Depletion Fraction that is based on a chemical mass balance approach using Zr as an immobile element. Chemical weathering accounts for 5 to 35% of the total mass lost due to denudation. We observe systematically higher chemical weathering intensities (CDFs) in sites with lower denudation rates (and vice versa), suggesting that weathering is supply-limited. Our measurements of soil elemental losses from 10 soil profiles suggest that the observed variation in chemical weathering is strongly associated

Removal of fission products from waste solutions using 16 different soil samples

International Nuclear Information System (INIS)

Bangash, M.A.; Hanif, J.

1997-01-01

Most of the nuclear sites use pits in the surrounding soils for the storage/disposal of low active waste (LAW) solutions. The characteristics of the soil if not suitable for the fixation or adsorption of the radioactive nuclides, may cause migration of these nuclides to hydrosphere. The phenomenon has the risk of radio toxic pollution for the living bodies therefore minerals composing the soil and their adsorption properties need to be investigated. For this purpose 16 different soil samples were collected from all over Pakistan. Mineralogical composition of the soils was determined by X-ray diffraction analysis. It was found that most of the samples contained clay minerals, illite, kaolinite and montmorillonite. Studies for the removal of fission products like, /sup 137/Cs. /sup 60/Sr and activation product /sup 60/CO from solution were carried out on these samples. The sorption experiments were performed by batch technique using radioactive as tracers. Distribution co-efficient were determined by mixing he element solution at pH 3 with the soil at soil solution ratios of 1 to 20. It is revealed from the experimental data that efficient removal of fission products from solutions is achieved by soil samples containing clay mineral montmorillonite, followed by little and kaolinite. These soils thus can be effectively used for the disposal of low level radioactive waste solutions without causing any environmental hazard. (author)

Separation of technetium from nuclear waste stream simulants. Final report

Energy Technology Data Exchange (ETDEWEB)

Strauss, S.H. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Chemistry

1995-09-11

The author studied liquid anion exchangers, such as Aliquat-336 nitrate, various pyridinium nitrates, and related salts, so that they may be applied toward a specific process for extracting (partitioning) and recovering {sup 99}TcO{sub 4}{sup {minus}} from nuclear waste streams. Many of the waste streams are caustic and contain a variety of other ions. For this reason, the author studied waste stream simulants that are caustic and contain appropriate concentrations of selected, relevant ions. Methods of measuring the performance of the exchangers and extractant systems included contact experiments. Batch contact experiments were used to determine the forward and reverse extraction parameters as a function of temperature, contact time, phase ratio, concentration, solvent (diluent), and other physical properties. They were also used for stability and competition studies. Specifically, the author investigated the solvent extraction behavior of salts of perrhenate (ReO{sub 4}{sup {minus}}), a stable (non-radioactive) chemical surrogate for {sup 99}TcO{sub 4}{sup {minus}}. Results are discussed for alternate organic solvents; metalloporphyrins, ferrocenes, and N-cetyl pyridium nitrate as alternate extractant salts; electroactive polymers; and recovery of ReO{sub 4}{sup {minus}} and TcO{sub 4}{sup {minus}}.

Bioremediation of oil-contaminated soil using Candida catenulata and food waste.

Science.gov (United States)

Joo, Hung-Soo; Ndegwa, Pius M; Shoda, Makoto; Phae, Chae-Gun

2008-12-01

Even though petroleum-degrading microorganisms are widely distributed in soil and water, they may not be present in sufficient numbers to achieve contaminant remediation. In such cases, it may be useful to inoculate the polluted area with highly effective petroleum-degrading microbial strains to augment the exiting ones. In order to identify a microbial strain for bioaugmentation of oil-contaminated soil, we isolated a microbial strain with high emulsification and petroleum hydrocarbon degradation efficiency of diesel fuel in culture. The efficacy of the isolated microbial strain, identified as Candida catenulata CM1, was further evaluated during composting of a mixture containing 23% food waste and 77% diesel-contaminated soil including 2% (w/w) diesel. After 13 days of composting, 84% of the initial petroleum hydrocarbon was degraded in composting mixes containing a powdered form of CM1 (CM1-solid), compared with 48% of removal ratio in control reactor without inoculum. This finding suggests that CM1 is a viable microbial strain for bioremediation of oil-contaminated soil with food waste through composting processes.

Antibiotic Resistance in Animal-waste-impacted Farm Soil: From Molecular Mechanisms to Microbial Evolution and Ecology

Science.gov (United States)

You, Y.; Ward, M. J.; Hilpert, M.

2012-12-01

Antibiotic resistance is a growing public health problem worldwide and the routine use of antibiotics in industrial animal production has sparked debate on whether this practice might constitute an environmental and public health concern. At a broiler farm, electromagnetic induction (EMI) surveying assisted soil sampling from a chicken-waste-impacted site and a marginally affected site. Consistent with the EMI survey, disparity existed between the two sites with regard to soil pH, tetracycline resistance (TcR) levels among heterotrophic culturable soil bacteria, and the incidence/prevalence of a number of tet and erm genes in the soils. No significant difference was observed in these aspects between the marginally affected site and several sites in a regional state forest that has not been in agricultural use for decades. Shortly after our sampling, the farm closed down and all the waste was removed. This unique change in situation offered us an unusual opportunity to examine the reversibility of any impact of the chicken waste on the soil microbial community. Two years after the event, several antibiotic resistance genes (ARGs) were still detected in the waste-impacted soil, and quantitative real-time PCR (qPCR) data showed that their relative abundance remained at substantial levels. A mobilizable tet(L)-carrying plasmid, pSU1, was identified in several chicken-waste-exposed soil bacteria of three different genera. Quantification of the plasmid's mobilization gene suggested that pSU1 had contributed to the prevalence and persistence of tet(L) in the waste-impacted soil. A second mobilizable tet(L)-carrying plasmid, pBSDMV9, isolated from the same soil, contained a region with 98.8% nucleotide identity to pSU1. The mosaic structure of the plasmids and the highly conserved nature of the tet(L) genes suggested that plasmid rearrangement favoring the acquisition of tet(L) may have occurred in the soil relatively recently. Additionally, in one chicken-waste

Separation processes for the pretreatment of high-level nuclear wastes at the Savannah River site - 59291

International Nuclear Information System (INIS)

Hobbs, David; Peters, Thomas; Taylor-Pashow, Kathryn; Fondeur, Fernando; Nash, Charles; Fink, Samuel; Herman, David; Marra, Jim

2012-01-01

Document available in abstract form only. Full text of publication follows: Separation methods for the pretreatment of the high-level nuclear wastes (HLW) at the Savannah River Site (SRS) include the Caustic Side Solvent Extraction (CSSX) process for cesium and adsorption/ion exchange for the removal of cesium, strontium and alpha-emitting actinides. The CSSX process uses a calixarene extractant in combination with phase modifiers in a hydrocarbon diluent. Monosodium titanate (MST), a hydrous metal oxide, is the baseline material for the removal of strontium and alpha-emitting radionuclides (principally Pu-238, Pu-239, Pu-240 and Np-237). Two pretreatment facilities, the Modular Caustic Side Solvent Extraction Unit (MCU) and the Actinide Removal Process (ARP) facility began radioactive operations at SRS in 2008. Together these facilities can treat approximately 4 million liters of waste per year. The same separation processes are also planned for the much larger Salt Waste Processing Facility (SWPF). The SWPF, which has a design throughput of about 27 million liters per year, is under construction and scheduled to begin radioactive operations in 2014. Current R and D activities for the CSSX process are focused on implementing a new solvent system and stripping flowsheet that offers enhanced extraction and stripping of cesium. This next generation solvent system features a different calixarene extractant, uses caustic instead of nitric acid

Benign hepatic portal venous gas following caustic ingestion

International Nuclear Information System (INIS)

Lewin, Maite; Tubiana, Jean-Michel; Pocard, Marc; Caplin, Scott; Parc, Rolland; Blain, Antoine

2002-01-01

Hepatic portal vein gas has been documented in numerous conditions and is traditionally regarded as a poor prognostic sign. There are, however, several reports of portal vein gas with a benign course. We report the first case of transient hepatic portal vein gas secondary to the ingestion of a caustic substance. The literature of hepatic portal vein gas in benign disease is reviewed. (orig.)

FUZZY LOGIC BASED HYBRID RECOMMENDER OF MAXIMUM YIELD CROP USING SOIL, WEATHER AND COST

Directory of Open Access Journals (Sweden)

U Aadithya

2016-07-01

Full Text Available Our system is designed to predict best suitable crops for the region of farmer. It also suggests farming strategies for the crops such as mixed cropping, spacing, irrigation, seed treatment, etc. along with fertilizer and pesticide suggestions. This is done based on the historic soil parameters of the region and by predicting cost of crops and weather. The system is based on fuzzy logic which gets input from an Artificial Neural Network (ANN based weather prediction module. An Agricultural Named Entity Recognition (NER module is developed using Conditional Random Field (CRF to extract crop conditions data. Further, cost prediction is done based on Linear Regression equation to aid in ranking the crops recommended. Using this approach we achieved an F-Score of 54% with a precision of 77% thus accounting for the correctness of crop production.

Tank waste remediation system: An update

International Nuclear Information System (INIS)

Alumkal, W.T.; Babad, H.; Dunford, G.L.; Honeyman, J.O.; Wodrich, D.D.

1995-02-01

The US Department of Energy's Hanford Site, located in southeastern Washington State, contains the largest amount and the most diverse collection of highly radioactive waste in the US. High-level radioactive waste has been stored at the Hanford Site in large, underground tanks since 1944. Approximately 217,000 M 3 (57 Mgal) of caustic liquids, slurries, saltcakes, and sludges have accumulated in 177 tanks. In addition, significant amounts of 90 Sr and 137 Cs were removed from the tank waste, converted to salts, doubly encapsulated in metal containers, and stored in water basins. The Tank Waste Remediation System Program was established by the US Department of Energy in 1991 to safely manage and immobilize these wastes in anticipation of permanent disposal of the high-level waste fraction in a geologic repository. Since 1991, significant progress has been made in resolving waste tank safety issues, upgrading Tank Farm facilities and operations, and developing a new strategy for retrieving, treating, and immobilizing the waste for disposal

The characterization of petroleum and creosote-contaminated soils: Class component analysis by thin layer chromatography with flame ionization detection

International Nuclear Information System (INIS)

Pollard, S.J.T.; Hrudey, S.E.; Fuhr, B.J.; Alex, R.F.; Holloway, L.R.

1992-01-01

The assessment and reclamation of coal tar, creosote and petroleum-contaminated sites is emerging as a major challenge to industry and the federal and provincial Canadian governments. Contaminants frequently include polynuclear aromatic compounds (PAH), several high molecular weight analogues of which are documented carcinogens. Adaptation of thin layer chromatography with flame ionization detection for the analysis of hydrocarbon-contaminated soils is described. The method is directly applicable to the analysis of oily waste extracts from petroleum and creosote wood preservative site soils and is capable of distinguishing between the saturate, aromatic and polar components of waste residues. The method provides a rapid, low cost class component analysis of heavy hydrocarbon waste extracts and is particularly useful for estimating the extent of weathering experienced by chronically exposed hydrocarbon wastes in the soil environment. As such, it is useful as a screening tool for a preliminary assessment of the biotreatability or inherent recalcitrance of hydrocarbon waste mixtures. 11 refs., 5 figs

Gully potential in soil-covered uranium waste impoundments

International Nuclear Information System (INIS)

Abt, S.R.; Hogan, S.A.; Johnson, T.L.

1994-01-01

Soil covers are routinely considered a design alternative to stabilize uranium waste impoundments. Gully intrusion into the cover is one of the greatest potential threats to the long-term stability of an impoundment. An investigation was conducted to estimate the maximum depth of gully intrusion, the approximate top width of the gully at the point of maximum incision, and the approximate location of the maximum intrusion. A large-scale laboratory study was conducted on seven embankments in which approximately 200 years of rainfall was simulated and the resulting gullies were documented. In addition, 11 gullies occurring in actual reclaimed impoundments were documented. An analysis of the laboratory and field data sets was performed in which the maximum depth of gully incision, top width of the gully, and location of the maximum gully incision were related to the pile height, tributary volume of runoff, and soil composition. These relations provide the designers with a means for assessing the cover design to meet the long-term stability of the waste

Soil mechanics and analysis of soils overlying cavitose bedrock

International Nuclear Information System (INIS)

Drumm, E.C.

1987-08-01

The stability of the residual soils existing at the West Chestnut Ridge Site, Oak Ridge Reservation, Tennessee, was evaluated. The weathered bedrock below this residual soil contains numerous solution cavities, and several karst features were identified. The West Chestnut Ridge site was evaluated with respect to deformation and collapse of the residual soil into the bedrock cavities. A finite element analysis investigated the effects of bedrock cavity radius, thickness of soil overburden, and surface surcharge upon the deformational and stability characteristics of the residual soil. The results indicate that for small cavity radii, the thickness of the soil cover has little effect on the zone of yielded soil. For large cavity radii, a smaller zone of distressed soil occurs under thick soil cover than under thin soil cover. Dimensionless curves are presented to enable the prediction of the vertical extent of the zone of yielded soil for a range of site geometries. Although the thick soil deposits (100 feet or greater) typically found on the ridges result in high stresses adjacent to the cavity, the area of the distressed or yielded soil is small and unlikely to extend to the surface. In addition, the surface deformation or subsidence is expected to be minimal. Thus, the siting of waste facilities on the ridges where the overburden is maximum would tend to reduce the effects of deformation into the cavities. 29 refs., 37 figs., 7 tabs

Long-term Effects of Organic Waste Fertilizers on Soil Structure, Tracer Transport, and Leaching of Colloids.

Science.gov (United States)

Lekfeldt, Jonas Duus Stevens; Kjaergaard, Charlotte; Magid, Jakob

2017-07-01

Organic waste fertilizers have previously been observed to significantly affect soil organic carbon (SOC) content and soil structure. However, the effect of organic waste fertilizers on colloid dispersibility and leaching of colloids from topsoil has not yet been studied extensively. We investigated how the repeated application of different types of agricultural (liquid cattle slurry and solid cattle manure) and urban waste fertilizers (sewage sludge and composted organic household waste) affected soil physical properties, colloid dispersion from aggregates, tracer transport, and colloid leaching from intact soil cores. Total porosity was positively correlated with SOC content. Yearly applications of sewage sludge increased absolute microporosity (pores 30 μm) compared with the unfertilized control, whereas organic household waste compost fertilization increased both total porosity and the absolute porosity in all pore size classes (though not significant for 100-600 μm). Treatments receiving large amounts of organic fertilizers exhibited significantly lower levels of dispersible colloids compared with an unfertilized control and a treatment that had received moderate applications of cattle slurry. The content of water-dispersible colloids could not be explained by a single factor, but differences in SOC content, electrical conductivity, and sodium adsorption ratio were important factors. Moreover, we found that the fertilizer treatments did not significantly affect the solute transport properties of the topsoil. Finally, we found that the leaching of soil colloids was significantly decreased in treatments that had received large amounts of organic waste fertilizers, and we ascribe this primarily to treatment-induced differences in effluent electrical conductivity during leaching. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Effect of Household Solid Waste on Initial Growth Performance of Acacia auriculiformis and Cedrela toona in Mycorrhiza Inoculated Soil

Directory of Open Access Journals (Sweden)

M.M. Abdullah-Al-Mamun

2015-09-01

Full Text Available Solid waste disposal and management became one of the major environmental concerns in Bangladesh. Realising the problem, the present study has been undertaken with a view to find a sound and effective way of bio-degradable solid waste management. The study was carried out in the nursery of Institute of Forestry and Environmental Sciences at University of Chittagong to determine the effects of solid waste and waste inoculated with mycorrhizal soil on initial growth performance of Acacia auriculiformis and Cedrela toona. Before planting the seedlings, decomposable waste and mycorrhiza inoculated decomposable waste were placed on the planting holes. Physical growth parameters of seedlings (shoot and root length, leaf and branch number, fresh and dry weight of shoot and root and nodulation status and the macro nutrients (N, P and K were recorded after six months of planting. The highest performance of physical parameters was recorded in the soil treated by mycorrhiza inoculated waste. Cedrela toona was represented by maximum nutrients uptake (N-2.60%, P-0.21% and K-2.34% respectively in the soil treated with mycorrhiza. In case of Acacia auriculiformis, N uptake was maximum (3.02% in control while K uptake was highest (1.27% in soil with waste and P (0.18% uptake was highest in the soil treated with mycorrhiza inoculated waste. Highest initial growth performance was revealed by seedlings treated with mycorrhiza inoculated waste. This study suggested to use mycorrhiza and waste for plantation purposes for hygienic disposal of solid waste and to reduce cost of cultivation.

A geochemical module for "AMDTreat" to compute caustic quantity, effluent quantity, and sludge volume

Science.gov (United States)

Cravotta,, Charles A.; Parkhurst, David L.; Means, Brent P; McKenzie, Bob; Morris, Harry; Arthur, Bill

2010-01-01

Treatment with caustic chemicals typically is used to increase pH and decrease concentrations of dissolved aluminum, iron, and/or manganese in largevolume, metal-laden discharges from active coal mines. Generally, aluminum and iron can be removed effectively at near-neutral pH (6 to 8), whereas active manganese removal requires treatment to alkaline pH (~10). The treatment cost depends on the specific chemical used (NaOH, CaO, Ca(OH)2, Na2CO3, or NH3) and increases with the quantities of chemical added and sludge produced. The pH and metals concentrations do not change linearly with the amount of chemical added. Consequently, the amount of caustic chemical needed to achieve a target pH and the corresponding effluent composition and sludge volume can not be accurately determined without empirical titration data or the application of geochemical models to simulate the titration of the discharge water with caustic chemical(s). The AMDTreat computer program (http://amd.osmre.gov/ ) is widely used to compute costs for treatment of coal-mine drainage. Although AMDTreat can use results of empirical titration with industrial grade caustic chemicals to compute chemical costs for treatment of net-acidic or net-alkaline mine drainage, such data are rarely available. To improve the capability of AMDTreat to estimate (1) the quantity and cost of caustic chemicals to attain a target pH, (2) the concentrations of dissolved metals in treated effluent, and (3) the volume of sludge produced by the treatment, a titration simulation is being developed using the geochemical program PHREEQC (wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/) that will be coupled as a module to AMDTreat. The simulated titration results can be compared with or used in place of empirical titration data to estimate chemical quantities and costs. This paper describes the development, evaluation, and potential utilization of the PHREEQC titration module for AMDTreat.

Insights into the biodegradation of weathered hydrocarbons in contaminated soils by bioaugmentation and nutrient stimulation.

Science.gov (United States)

Jiang, Ying; Brassington, Kirsty J; Prpich, George; Paton, Graeme I; Semple, Kirk T; Pollard, Simon J T; Coulon, Frédéric

2016-10-01

The potential for biotransformation of weathered hydrocarbon residues in soils collected from two commercial oil refinery sites (Soil A and B) was studied in microcosm experiments. Soil A has previously been subjected to on-site bioremediation and it was believed that no further degradation was possible while soil B has not been subjected to any treatment. A number of amendment strategies including bioaugmentation with hydrocarbon degrader, biostimulation with nutrients and soil grinding, were applied to the microcosms as putative biodegradation improvement strategies. The hydrocarbon concentrations in each amendment group were monitored throughout 112 days incubation. Microcosms treated with biostimulation (BS) and biostimulation/bioaugmentation (BS + BA) showed the most significant reductions in the aliphatic and aromatic hydrocarbon fractions. However, soil grinding was shown to reduce the effectiveness of a nutrient treatment on the extent of biotransformation by up to 25% and 20% for the aliphatic and aromatic hydrocarbon fractions, respectively. This is likely due to the disruption to the indigenous microbial community in the soil caused by grinding. Further, ecotoxicological responses (mustard seed germination and Microtox assays) showed that a reduction of total petroleum hydrocarbon (TPH) concentration in soil was not directly correlable to reduction in toxicity; thus monitoring TPH alone is not sufficient for assessing the environmental risk of a contaminated site after remediation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Earthworms as colonisers: Primary colonisation of contaminated land, and sediment and soil waste deposits

NARCIS (Netherlands)

Eijsackers, H.J.P.

2010-01-01

This paper reviews the role of earthworms in the early colonisation of contaminated soils as well as sediment and waste deposits, which are worm-free because of anthropogenic activities such as open-cast mining, soil sterilisation, consistent pollution or remediation of contaminated soil. Earthworms

The role of chemical weathering in the neutralization of acid rain

International Nuclear Information System (INIS)

Asolekar, S.R.

1991-01-01

Chemical weathering of soils/minerals is an important process which controls the long-term neutralization of acid rain as well as the quality of surface water, ground water, and oceans. Few laboratory studies have been conducted to evaluate the response of real whole soils or soil fractions to acidification. In this research experiments were performed in a laboratory semi-continuous pH-stat reactor over the pH range 2.7 to 4.7 using Band C-horizon soil fractions from the Bear Brook Watershed, Maine, and in presence/absence of 1 to 20 mmol/L oxalate ligand in the bulk solution. Acid consumption rate and the corresponding release rates of sodium, calcium, magnesium, aluminum, iron, and silica were monitored in the laboratory reactor. Both H + -ion and oxalate promoted weathering rates were fractional order based on the concentration in bulk solution. The mixed kinetic model for the soils is: WR T = WR H + WR ox = K H (H + ) m + K ox [OX TD ] p , where m and p are fractional orders. The hydrogen ion consumption rates were approximately equal to cation release rates on an equivalent basis for hydrogen ion promoted weathering situations where secondary precipitation was unlikely (pH < 4.7) as well as for weathering of C-horizon light fraction at pH 4.0 and oxalate concentration 1 and 5 mmol/L. The relative proportions of released species were in the neighborhood of stoichiometric ratios of bulk soil chemistry for weatherable minerals in Band C-horizon soil fractions. The experimental ratios of H/Si, Al/Si, Fe/Si, Ca/Si, Na/Si, and Mg/Si for linear weathering rates of Band C-horizon soil fractions were fairly constant in the presence and absence of oxalate ligand and strongly suggested that silica may be used as a tracer for primary mineral weathering assuming quartz is inert

Effect of intermediate soil cover on municipal solid waste decomposition.

Science.gov (United States)

Márquez-Benavides, L; Watson-Craik, I

2003-01-01

A complex series of chemical and microbiological reactions is initiated with the burial of refuse in a sanitary landfill. At the end of each labour day, the municipal solid wastes (MSW) are covered with native soil (or an alternative material). To investigate interaction between the intermediate cover and the MSW, five sets of columns were set up, one packed with refuse only, and four with a soil-refuse mixture (a clay loam, an organic-rich peaty soil, a well limed sandy soil and a chalky soil). The anaerobic degradation over 6 months was followed in terms of leachate volatile fatty acids, chemical oxygen demand, pH and ammoniacal-N performance. Results suggest that the organic-rich peaty soil may accelerate the end of the acidogenic phase. Clay appeared not to have a significant effect on the anaerobic degradation process.