Technology:
Steam Enhanced Extraction (SEE)
- System included shallow vapor extraction wells, shallow and deep steam injection wells, vacuum-enhanced groundwater/vapor extraction wells, deep groundwater extraction wells, and two vacuum extraction units
- 65 steam injection wells, including 39 shallow wells screened a depth of 35 ft bgs and 26 deep wells screened at a depth of 46 ft bgs
- Steam supplied by a 294 kilowatt boiler at pressures ranging from 3 to 7 psi; during operation, soil temperatures ranged from 84°F to 140°F, and groundwater temperatures ranged from 68°F to 165°F
- SVE system - 186 shallow wells and 76 combination groundwater/vapor extraction wells; two vapor extraction units operated at 150 to 250 scfm at 7 to 15 inches of mercury
- Groundwater extracted from the combination groundwater/vapor extraction wells at a rate ranging from 15 to 30 gpm; treated using air stripping and activated carbon
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Cleanup Authority:
State voluntary cleanup
Contacts:
Site Contact
Brian LeMaster
Environmental and Safety Specialist
A.G. Communication Systems
Northlake, IL 60164 | Technical Contact/Vendor
Timothy Adams
ENSR Corporation
27755 Diehl Rd.
Warrenville, IL 60555
Telephone: (630) 836-17000
E-mail: tadams@ensr.com |
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Contaminants:
Chlorinated solvents (TCE, cis-1,2-DCE), petroleum hydrocarbons (xylene and benzene)
- TCE concentration of greater than 45,000 ug/L in groundwater |
Waste Source:
Spills and leaks from the manufacture of telecommunications equipment |
Type/Quantity of Media Treated:
Source zone (saturated and unsaturated)
- Estimated 330,000 cubic yards treated |
Purpose/Significance of Application:
Use of SEE in conjunction with SVE to treat a source zone (saturated and unsaturated) contaminated with chlorinated solvents |
Regulatory Requirements/Cleanup Goals:
- The remedial objective was to obtain IEPA approved closure under Tiered Approach to Corrective Action guidelines
- The proposed closure strategy was to use site-specific parameters to calculate a first order degradation constant and demonstrate that there are no on-site or off-site receptors at risk from volatile organic hydrocarbons in soil or groundwater |
Results:
- Average TCE groundwater concentrations reduced from approximately 20,000 ug/L to <1,000 ug/L over the period from September 1995 to September 1997
- Data from individual wells showed reductions of >90% for TCE and DCE from December 1995 to October 1997
- Through November 1999, more than 33,000 lbs of hydrocarbons had been removed from soil vapor and groundwater; approximately two-thirds of the contaminant mass was removed as vapor from the two VES units
- According to the vendor, based on the site-specific first order degradation constant, the calculated groundwater concentrations at the point of compliance (property boundary) met Class I remediation objectives; where the soil concentrations beneath the building exceeded the soil remediation objectives, a theoretical groundwater concentration leached from the soil was calculated and, along with the site specific degradation constant, was shown to meet the Class I remediation objectives at the point of compliance |
Cost Factors:
- Actual cost for the application was $4.9 million and $13 to 15 per cubic yard treated, including the cost of the pilot test, system design and installation, five years of operation and maintenance, and negotiations with IEPA |
Description:
The A.G. Communications site, located near Chicago, IL, operated as a telecommunications manufacturing facility from the 1950s through the early 1990s. TCE and mineral spirits used in manufacturing operations were stored in underground storage tanks (UST). During the decommissioning of the manufacturing facility, TCE, DCE and components of mineral spirits, including xylene and benzene, were found in soil and groundwater in the vicinity of the former tank farm area and beneath the manufacturing plant. The site was remediated under the Illinois Environmental Protection Agency (IEPA) voluntary site remediation program (SRP). A SEE system was pilot tested at the site from January through July 1994, and full-scale remediation was performed from September 1995 to November 1999.
The full-scale system included shallow vapor extraction wells, shallow and deep steam injection wells, vacuum-enhanced groundwater/vapor extraction wells, deep groundwater extraction wells, and two vacuum extraction units. Through November 1999, a total of 33,000 pounds of hydrocarbons had been removed from soil vapor and groundwater, with TCE and DCE concentrations reduced by more than 90%. In addition to SEE, chemical oxidant flushing using chlorine dioxide (Cl02) was performed in recalcitrant source areas. According to the vendor, this approach was used to enhance TCE partitioning from soil for removal through the groundwater/vapor extraction wells, and redox levels of -100 to -200 mV were achieved. No additional information about the flushing was provided. |
