Technology:
Ex situ bioremediation of soils using the DARAMEND process
- main treatment area, high Metolachlor test cell and static control cell
- alternated aerobic and anaerobic conditions (10 cycles)
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Cleanup Authority:
Information not provided
Regulatory Point of Contact:
Information not provided | USACE Contacts:
Information not provided |
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Contaminants:
Semivolatiles - halogenated
- organic pesticides/herbicides, including Metolachlor, 2,4-D, Dinoseb, Atrizine
- Metolachlor - initial concentrations as high as 170 mg/kg |
Waste Source:
Contamination resulting from formulating and warehousing pesticides and herbicide |
Type/Quantity of Media Treated:
Soil - 200 tons. Excavated from the site and stockpiled for treatment. |
Purpose/Significance of Application:
Demonstrate the performance of the DARAMEND process for treating Metolachlor-contaminated soils |
Regulatory Requirements/Cleanup Goals:
Information on specific cleanup objectives was not included in this report. Performance and results are described in terms of reductions in concentrations of contaminants. |
Results:
- Concentrations of Metolachlor in the main treatment cell were reduced from initial levels ranging from 48 to 84 mg/kg to below a detection level of 1.0 mg/kg. Concentrations in the high Metolachlor (HM) test cell were reduced from initial concentrations of 170 mg/kg to 38 mg/kg.
- Within the HM test cell, only the top 30 cm of a 60 cm deep cell were tilled during the demonstration. According to the vendor, effective treatment may not have occurred throughout the cell. A sample of the top 30 cm only of the HM test cell showed Metolachlor concentrations of 11.8 mg/kg. |
Cost Factors:
- No costs were reported for the demonstration.
- The vendor used data from the demonstration to estimate that the cost for treating the estimated 600 tons of contaminated soil that remained at the Novartis site would be $111,600 or $186/ton (in Canadian dollars). |
Description:
Environmental Technologies Program, Environment Canada's Development and Demonstration of Site Remediation Technologies Program, and by Grace. The demonstration, conducted from March 1996 to September 1997, involved 200 tons of soil from the Novartis site that had been excavated and stockpiled. The soil was contaminated with Metolachlor, Dinoseb, Atrizine, and 2,4-D.
The ex situ treatment area included three cells - the main treatment cell (180 tons), the high Metolachlor (HM) test cell (10 tons), and a static control cell (10 tons). Soils were placed in the cells which were located within a greenhouse enclosure. The demonstration was designed to cycle between aerobic conditions and anaerobic conditions to promote the degradation of the contaminants. During the demonstration, the soil was subjected to a total of ten cycles. DARAMEND amendments and inorganic amendments (for example multivalent metal) were added to the soil. The soil was covered with a tarp during the anaerobic cycle and was tilled during the aerobic cycle. Data from the treated soil in the main treatment cell showed that concentrations of contaminants were reduced to below detection levels. Metolachlor was reduced from initial concentrations ranging from 48 to 84 mg/kg to below the detection limit of 1.0 mg/kg. Levels of Metolachlor within the HM cell were reduced from 170 mg/kg to 38 mg/kg. However, according to Grace, only the top 30 cm of the 60 cm deep cell were tilled during the demonstration such that the treatment was not effective throughout the entire cell. Data from the top 30 cm only of the HM cell showed that Metolachlor levels had been reduced to 11.8 mg/kg.
The projected cost to treat the remaining 600 tons of soil at the Novartis site using this technology was $111,600 or $186/ton in Canadian dollars. Grace noted that because these costs were based on the demonstration, which included extensive process monitoring and waste analysis costs, the projected cost for a full-scale application would be significantly less. |
