In situ solidification/stabilization using EnvirobondTM process
- EnvirobondTM is a combination of proprietary powder and solution developed by Rocky Mountain Remediation Services, L.L.C. (RMRS)
- Consists of a mixture of additives containing oxygen, nitrogen, and phosphorus, with each additive having an affinity for a specific class of metals
- Forms metal complexes that immobilize toxic metals, preventing them from leaching
- Applied at 10 experimental units at a trailer park and one experimental unit at an inactive pottery factory
- Powder applied to surface of experimental unit using a fertilizer drop spreader, and liquid applied over the powder using a watering can; powder and liquid mixed into soil using a garden tiller
- Flyash used to adjust soil pH of each experimental unit to approximately 7.0. Thin layer distributed over surface of experimental unit and tilled into experimental unit.
|EPA Project Manager|
Office of Research and Dvelopment
U.S. Environmental Protection Agency
26 W. Martin Luther King Drive
Cincinnati, OH 45268
(513) 569-7669 (phone)
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|Technology Developer |
Rocky Mountain Remediation Services
1819 Denver West Drive
Building 26, Suite 200
Golden, CO 80401
(303) 215-6686 (phone)
(303) 215-6786 (fax)
Ohio Environmental Protection Agency
Southeast District Office
2195 Front Street
Logan, OH 43139-9031
Lead - 382 mg/L TCLP at inactive pottery facility; 0.05 mg/L TCLP at trailer park
Improper disposal of lead-containing waste generated from pottery-making processes
Type/Quantity of Media Treated:
- Two areas treated - a trailer park and an inactive pottery facility
- Units at trailer park measured 5 ft X 5 ft, and unit at pottery factory measured 3 ft wide X 6 ft long
- Depth of demonstration in all units was limited to upper 6 inches of soil
- Total volume of soil treated was approximately 5 cy
Purpose/Significance of Application:
To evaluate effectiveness of in situ solidification/stabilization for treating lead in soil
Regulatory Requirements/Cleanup Goals:
- Reduce concentrations of leachable lead in soil to meet the RCRA/HSWA alternative universal treatment standards (UTS) for lead in contaminated soil; this corresponds to a TCLP lead concentration no higher than one of the following: 1) 7.5 mg/L, or 2) 10 percent of the lead concentration in the TCLP extract from untreated soil.
- Decrease soil lead bioaccessibility by 25 percent or more, as defined by the Simplified In Vitro Test Method for Determining Soil Lead and Arsenic Bioaccessibility
- Mean TCLP lead concentration at the inactive pottery factory was reduced from 382 mg/L to 1.4 mg/L - a reduction of over 99 percent, meeting the alternative UTS for soil
TCLP lead concentrations in all treated and untreated soil samples from trailer park were either at or slightly higher than the detection limit of 0.05 mg/L, and were not used to evaluate objective
Soil lead bioaccessibility at the trailer park was reduced by approximately 12.1 percent; soil lead bioaccessibility was not evaluated at the pottery facility.
- The total cost for the demonstration was approximately $26,000, broken down into 12 separate categories. The unit cost for the demonstration was $5,176 per cy.
- These costs were used to estimate the cost for a typical application of EnvirobondTM at full scale.
- Full scale estimate was a site-specific total cost of $33,220, with a unit cost of $41.16 per cy for treating 807 cy of lead-contaminated soil at a 1-acre site within the CRPAC
The CRPAC is a former pottery manufacturing area located in eastern Ohio. Lead was used in the glazing step of the pottery finishing process, and improper disposal of the lead-containing waste resulted in contamination of the upper portion of soil in the area. A field demonstration of in situ solidification/stabilization using the EnvirobondTM process was performed at two sites (a trailer park and an inactive pottery facility) within the CRPAC in September 1998.
The demonstration involved applying EnvirobondTM at 10 experimental units at the trailer park and one experimental unit at the inactive pottery facility, treating a total of approximately 5 cy of soil. The two main goals of the demonstration were to evaluate whether EnvirobondTM could reduce concentrations of leachable lead in the soil to meet the alternative UTS and whether it could decrease the portion of total lead in soil that is bioaccessible, as measured by the Simplified In Vitro Test Method for Determining Soil Lead and Arsenic Bioaccessibility, by at least 25 percent. Data from the demonstration indicated that the mean TCLP lead concentration at the inactive pottery factory was reduced from 382 mg/L to 1.4 mg/L, which meets the standards. Data from the trailer park were not used to evaluate the goal because TCLP lead concentrations in all treated and untreated soil samples from this location were either at or slightly higher than the detection limit of 0.05 mg/L. Analysis of the data for the second goal showed that soil lead bioaccessibility had been reduced by approximately 12.1 percent, which was less than the project goal of at least 25 percent.
The total cost for the demonstration was $26,000 and the projected total cost for use of this technology to treat 807 cy of soil at full scale was $33,220, with a unit cost of $41.16 per cy.