Pump and Treat of Contaminated Groundwater at the LaSalle Electrical Superfund Site, LaSalle, Illinois

Site Name:

LaSalle Electrical Superfund Site


LaSalle, Illinois

Period of

Status: Ongoing
Report covers: 12/92 - 5/97


Full-scale cleanup (interim results)


Ecology & Environment, Inc.
ThermoCor Kimmons

Pump and Treat
- Groundwater is extracted using 3 infiltration trenches, at an average total extraction rate of 17 gpm
- Extracted groundwater is treated with oil/water separation, air stripping, and carbon adsorption, and discharged to a POTW

Cleanup Authority:
CERCLA Remedial
- ROD Date: 3/30/88

Point of Contact:
Rich Lange
Illinois EPA (IEPA)
2200 Churchill Road
P.O. Box 19276
Springfield, IL 62794-9276
(815) 223-1126
Additional Point of Contact:

PCBs and chlorinated solvents
- Maximum concentrations detected in 1980-1981 were PCBs (760,000 mcg/L), TCE (13,341 mcg/L), trans-1,2-DCE (7,152 mcg/L), 1,1,1-TCA (3,123 mcg/L), and vinyl chloride (500 mcg/L)

Waste Source:
Spills from capacitor cleaning and spreading polychlorinated biphenyl (PCB)-laden waste oils as a dust suppressant

Type/Quantity of Media Treated:
- 23 million gallons treated as of May 1997 - DNAPL observed in groundwater on site - Groundwater is found at 3-5 ft bgs - Contaminants are primarily found in a shallow aquifer at the site - Hydraulic conductivity ranges from <0.01 to 0.22 ft/day

Purpose/Significance of Application:
Relatively high unit cost; system consists of collection trenches instead of extraction wells; relatively low groundwater flow.

Regulatory Requirements/Cleanup Goals:
- The goal of this remedy is to restore the groundwater to primary drinking water standards; these are PCBs (0.5 mcg/L), 1,2-DCE (5 mcg/L), 1,1-DCA (5 mcg/L), TCE (5 mcg/L), PCE (100 mcg/L), 1,1,1-TCA (200 mcg/L), and vinyl chloride (2 mcg/L).
- Containment was not a specific goal of this remediation.

- Groundwater monitoring results for the deep aquifer (through March 1996) and shallow aquifer (through May 1997) indicate that total contaminant concentrations have not been reduced below cleanup goals. At specific monitoring wells, contaminant concentrations fluctuate with precipitation rates.
- From 1993 to September 1997, the system removed approximately 127 pounds of contaminants from the groundwater; 1,1,1-TCA makes up the majority of the mass removed by the treatment system

Cost Factors:
Actual costs for pump and treat are approximately $6,138,576 ($5,314,576 in capital and $824,000 in O&M), which correspond to $266 per 1,000 gallons of groundwater extracted and $48,000 per pound of contaminant removed.

LaSalle Electrical Utilities operated this site as a manufacturing facility for electrical equipment from 1940 to 1978. PCBs and chlorinated solvents were used in the manufacturing process during this time. As a result of complaints, government agencies issued several orders in 1975 against the company for its manufacturing and waste handling practices. In 1980 and 1981, Illinois EPA performed sampling at the site which confirmed the presence of PCB and VOC contamination in soils and groundwater. The site was placed on the NPL in December 1982 and a ROD was signed in March 1988.

The groundwater collection system is a passive design that uses three infiltration trenches instead of wells. The three trenches form an H-pattern, and drain to a wet well, which in turn is pumped to the treatment unit. The trenches were installed horizontally at a depth of approximately 17 to 25 ft bgs. Approximately 127 pounds of contaminants (primarily 1,1,1-TCA) have been removed from the groundwater over 45 months, however the system has not achieved the cleanup goals. As of May 1997, no design modifications were being considered for this site.