The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform
Peter J. Ashley - One of the best experts on this subject based on the ideXlab platform.
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Biosolids compost amendment for reducing soil lead hazards: A pilot study of Orgro® amendment and grass seeding in urban yards
Science of The Total Environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles A Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations N800 mg Pb kg 1 were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6–8 cm depth of OrgroR Biosolids compost (110–180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards.
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Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro amendment and grass seeding in urban yards.
The Science of the total environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations >800 mg Pb kg(-1) were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6-8 cm depth of Orgro Biosolids compost (110-180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards. At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg(-1)) and 67% (from 1381 to 453 mg kg(-1)) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg(-1), respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.
Rufus L. Chaney - One of the best experts on this subject based on the ideXlab platform.
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Biosolids compost amendment for reducing soil lead hazards: A pilot study of Orgro® amendment and grass seeding in urban yards
Science of The Total Environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles A Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations N800 mg Pb kg 1 were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6–8 cm depth of OrgroR Biosolids compost (110–180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards.
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Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro amendment and grass seeding in urban yards.
The Science of the total environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations >800 mg Pb kg(-1) were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6-8 cm depth of Orgro Biosolids compost (110-180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards. At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg(-1)) and 67% (from 1381 to 453 mg kg(-1)) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg(-1), respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.
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Effect of Biosolids processing on lead bioavailability in an urban soil
Journal of Environmental Quality, 2003Co-Authors: Sally Brown, Rufus L. Chaney, Judith HallfrischAbstract:The potential for Biosolids products to reduce Pb availability in soil was tested on a high Pb urban soil with Biosolids from a treatment plant that used different processing technologies. High Fe Biosolids compost and high Fe + lime Biosolids compost from other treatment plants were also tested. Amendments were added to a Pb-contaminated soil (2000 mg kg -1 Pb) at 100 g kg -1 soil and incubated for 30 d. Reductions in Pb bioavailability were evaluated with both in vivo and in vitro procedures. The in vivo study entailed feeding a mixture of the Pb-contaminated soil and AIN93G Basal Mix to weanling rats. Three variations of an in vitro procedure were performed as well as conventional soil extracts [diethylenetriaminepentaacetic acid (DTPA) and Ca(NO 3 ) 2 ] and sequential extraction. Addition of the high Fe compost reduced the bioavailability of soil Pb (in both in vivo and in vitro studies) by 37 and 43%, respectively. Three of the four compost materials tested reduced Pb bioavailability more than 20%. The rapid in vitro (pH 23) data had the best correlation with the in vivo bone results (R = 0.9). In the sequential extract, changes in partitioning of Pb to Fe and Mn oxide fractions appeared to reflect the changes in in vivo Pb bioavailability. Conventional extracts showed no changes in metal availability. These results indicate that addition of 100 g kg -1 of high Fe and Mn Biosolids Composts effectively reduced Pb availability in a high Pb urban soil.
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using Biosolids Composts and tailor made Biosolids mixtures in remediating urban and brownfield sites and other metal contaminated soils
Proceedings of the Water Environment Federation, 2001Co-Authors: Rufus L. Chaney, Sally Brown, James A Ryan, Judith Hallfrisch, I Stuczynski, Harry ComptonAbstract:7 Abstract: Our research on beneficial use of Biosolids has been shown in laboratory and field studies that amendment of urban soils can reduce plant uptake of soil Pb and the bioavailability of Pb in ingested soil. Similar remediation is achieved by Biosolids plus limestone at Pb, Zn, and Cd contaminated soils at Superfund Sites. Further, by combining other byproducts of agriculture, industry and urban industries with Biosolids, and processing to fit the end use (composted or stabilized as needed), we have illustrated the use of "Tailor-Made Biosolids Mixtures" to inactivate soil Pb in urban soils and remediate dead soils. High Fe, P, and fertility of Biosolids amended soils aid in precipitation and adsorption of soil Pb, and adsorption of soil Cd, Zn, and other elements. In the case of Pb, we have conducted soil feeding tests to measure the effectiveness of Biosolids constituents and processing on bioavailability of Pb in the amended soils. For urban soils from Baltimore, bioavailability of Pb has been reduced by as much as 60% at 30 days after adding 224 t/ha of high Fe Biosolids or composted Biosolids. Other research has shown that part of this reduction in bioavailability is the formation of chloropyromorphite, a very insoluble Pb mineral. Thus the remediation effectiveness is expected to only increase with time as precipitation is more complete. The low solubility of both Pb and P in soils slows the precipitation reaction, but the high Fe and P in the Biosolids provides strong selective adsorption of metals such as Pb. Urban soils are statistically Pb contaminated by many sources. Houseside soils with 5% Pb have been found even in rural settings when high Pb paint fell onto soil. Historic automotive and stack emission Pb also contributes to urban soil Pb. Most US children who have excessive blood-Pb live in older center cities where their environment is high in Pb, although interior paint Pb remains the most important source of excessive Pb absorption. Thus remediation of soil Pb can be achieved at little cost by incorporation of composted Fe rich Biosolids and seeding or sodding. Superfund addresses the soil Pb risk of only a small fraction of US children because urban soil Pb does not come from a known industrial source. The combination of high fertility and improved soil condition and water holding capacity from the Biosolids amendment supports strong cover with turf grasses, making soil transfer to children much more difficult. Using composted (and some other treated) Biosolids products rich in Fe and P (Class A disinfection) in urban soils can provide important public health benefits by reducing Pb risk from urban soils. This same approach is effective in remediation/revegetation of risks at hazardous
Mark R. Farfel - One of the best experts on this subject based on the ideXlab platform.
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Biosolids compost amendment for reducing soil lead hazards: A pilot study of Orgro® amendment and grass seeding in urban yards
Science of The Total Environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles A Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations N800 mg Pb kg 1 were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6–8 cm depth of OrgroR Biosolids compost (110–180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards.
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Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro amendment and grass seeding in urban yards.
The Science of the total environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations >800 mg Pb kg(-1) were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6-8 cm depth of Orgro Biosolids compost (110-180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards. At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg(-1)) and 67% (from 1381 to 453 mg kg(-1)) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg(-1), respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.
Anna O. Orlova - One of the best experts on this subject based on the ideXlab platform.
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Biosolids compost amendment for reducing soil lead hazards: A pilot study of Orgro® amendment and grass seeding in urban yards
Science of The Total Environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles A Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations N800 mg Pb kg 1 were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6–8 cm depth of OrgroR Biosolids compost (110–180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards.
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Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro amendment and grass seeding in urban yards.
The Science of the total environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations >800 mg Pb kg(-1) were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6-8 cm depth of Orgro Biosolids compost (110-180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards. At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg(-1)) and 67% (from 1381 to 453 mg kg(-1)) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg(-1), respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.
Peter S. J. Lees - One of the best experts on this subject based on the ideXlab platform.
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Biosolids compost amendment for reducing soil lead hazards: A pilot study of Orgro® amendment and grass seeding in urban yards
Science of The Total Environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles A Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations N800 mg Pb kg 1 were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6–8 cm depth of OrgroR Biosolids compost (110–180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards.
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Biosolids compost amendment for reducing soil lead hazards: a pilot study of Orgro amendment and grass seeding in urban yards.
The Science of the total environment, 2005Co-Authors: Mark R. Farfel, Anna O. Orlova, Rufus L. Chaney, Peter S. J. Lees, Charles Rohde, Peter J. AshleyAbstract:In situ inactivation of soil Pb is an alternative to soil removal and replacement that has been demonstrated in recent years at industrial sites with hazardous soil Pb concentrations. Most children exposed to elevated soil Pb, however, reside in urban areas, and no government programs exist to remediate such soils unless an industrial source caused the contamination. Modern regulated Biosolids Composts have low Pb concentrations and low bioaccessible Pb fractions and can improve grass growth on urban soils. High Fe and P Biosolids Composts can reduce the bioavailability and bioaccessibility of soil Pb and can aid in establishing vegetation that would reduce soil transfer into homes. For these reasons, we conducted a field test of their use to reduce Pb bioaccessibility in urban soils in Baltimore, MD USA. We chose Biosolids compost for its expected reduction in the bioaccessible Pb fraction of urban soils, ease of use by urban residents, and ability to beautify urban areas. Nine urban yards with mean soil Pb concentrations >800 mg Pb kg(-1) were selected and sampled at several distances from the house foundation before soil treatment. The soils were rototilled to 20 cm depth to prepare the sites, and resampled. The yards were then amended with 6-8 cm depth of Orgro Biosolids compost (110-180 dry t/ha) rich in Fe and P, mixed well by rototilling, and resampled. Kentucky bluegrass (Poa pratensis) was seeded and became well established. Soils were resampled 1 year later. At each sampling time, total soil Pb was measured using a modified U.S. EPA nitric acid hotplate digestion method (SW 846 Method 3050) and bioaccessible Pb fraction was measured using the Solubility/Bioaccesibility Research Consortium standard operating procedure with modifications, including the use of glycine-buffered HCl at pH 2.2. Samples of untreated soils were collected from each yard and mixed well to serve as controls for the Pb bioaccessibility of field treated soils over time independent of positional variance within yards. At 1-year post-treatment, grass cover was healthy and reductions in bioaccessible Pb concentrations compared to pre-tillage were 64% (from 1655 to 595 mg kg(-1)) and 67% (from 1381 to 453 mg kg(-1)) at the sampling lines closest to the houses. Little or no reduction in bioaccessible Pb concentration was observed at sampling lines more remote from the house that also had the lowest bioaccessible Pb concentrations at pre-tillage (620 and 436 mg kg(-1), respectively). For the control soils, changes over time in total Pb and bioaccessible Pb concentrations and the bioaccessible Pb fraction were insignificant. This study confirms the viability of in situ remediation of soils in urban areas where children are at risk of high Pb exposure from lead in paint, dust and soil.
