Pump and Treat
- Groundwater is extracted using 12 wells at an average total pumping rate of 8 gpm
Extracted groundwater is treated with filtration (for iron), pH adjustment, air stripping, carbon adsorption, and filtration
- Treated groundwater is reinjected through 14 wells
- ROD Date: 9/23/88
|EPA Point of Contact:|
Ernest R. Franke, RPM
U.S. EPA Region 6
1445 Ross Ave., Suite 1200
Dallas, TX 75202-2733
|State Point of Contact:|
TNRCC, Mail Code 144
12100 Park Circle
Austin, TX 78753
Radian International LLC
9801 Westheimer, Suite 500
Houston, TX 77042
- Maximum concentration of TCE detected in 1988 was 1,200 mg/L
Disposal of punctured trichloroethene drums on the ground surface
Type/Quantity of Media Treated:
- 13 million gallons treated as of October 1996
- DNAPL was suspected in groundwater at this site
- Groundwater is found at 20-25 ft bgs
- Extraction wells are located in 3 aquifers
- Hydraulic conductivity ranges from 0.14 to 25.5 ft/day
Purpose/Significance of Application:
Relatively high unit cost for treatment, due to high capital costs and small quantity of groundwater extracted.
Regulatory Requirements/Cleanup Goals:
- A remedial goal was established for TCE of 5 mcg/L, based on the maximum contaminant level, that must be met throughout all affected aquifers.
- A goal for the extraction system is hydraulic containment of the plume.
- From 1994 to 1996, concentrations of contaminants were reduced in some wells, but remain above the cleanup goal in the silty, shallow, and intermediate zone wells. In some shallow zone wells, concentrations have increased to higher than 1,000 mcg/L over this period. Through 1996, approximately 4,960 pounds of contaminants have been removed from the groundwater. Further plume delineation was being performed at the time of this report.
- Hydraulic containment of the plume has not been achieved, according to the TNRCC manager.
Actual costs for pump and treat were $2,547,387 ($2,104,910 in capital and $442,477 in O&M), which correspond to $196 per 1,000 gallons of groundwater extracted and $514 per pound of contaminant removed.
Sol Lynn owned and operated this site as Industrial Transformers, a scrap metal and electrical transformer reclamation facility, from 1971 through 1978. Sol Lynn then leased the property to Ken James, who operated the site as Sila King, Inc., a chemical supply business, in 1979 and 1980. During the fall of 1971, the city of Houston Water Pollution Control Division discovered that workers at Industrial Transformers poured oil out of electrical transformers onto the ground during transformer dismantling. In 1981, reports of strong odors originating from the site were brought to the attention of the Texas Department of Water Resources. Upon inspection, approximately 75 punctured drums were found scattered about the property. A remedial investigation conducted from 1984 through 1991 showed elevated levels of PCBs in surficial soils and TCE in shallow soils and groundwater, and that the plume had migrated off site. The Sol Lynn/Industrial Transformer site was listed on the NPL in March 1989 and a ROD was signed in September 1988.
The extraction system used at this site consists of 12 wells - five wells in the silty zone, six wells in the shallow sand zone, and one well in a lower, intermediate aquifer. Eight of the 12 wells are located across the centerline of the plume along the site's northern boundary. This placement serves to intercept contaminated groundwater as it moves across the site and to draw back the off-site plume. As of 1996, concentrations of contaminants were reduced in some wells, but remain above the cleanup goal in the silty, shallow, and intermediate zone wells. Although remediation is not complete, the site engineers shut down the extraction system in October 1996. Extraction well pipes were leaking and fouled, and the extraction system lost plume containment. Currently, the site is being reevaluated. Aquifer usage, alternative remedial actions, and plume boundaries are being examined.