Remediation Status: In active remediation

Why the technology was selected:
ISCO (sodium permanganate)was selected because the source area was relatively small and located under the floor slab of the facility in the location of the former drycleaning machines. The soil horizon under the building, 1 to 2 feet in thickness, is very thin and is mostly fill gravel on top of bedrock. It was thought that ISCO would remediate the contamination relatively quickly and be more cost effective.

Date implemented:
1st ISCO Injection Event - October 18, 2006

Final remediation design:
Four injection wells of 1-inch diameter PVC screen were installed in the area of the former drycleaning machine to the soil/bedrock interface (approximately 2 feet bgs). 1). 1st ISCO Injection Event - 34 gallons of 10% sodium permanganate solution was injected into each injection well. During the event it was found that one of the injection wells had significant breakthrough and was deemed unusable and abandoned. The remaining solution earmarked for this well was then placed in the three remaining injection wells. 2). 2nd Injection Event - December 7, 2006. 50 gallons of 10% sodium permanganate solution was injected into each of the three injection wells. 3). 3rd Injection Event - January 26, 2007. 50 gallons of 10% sodium permanganate solution was injected into each of the three injection wells. 4). 4th Injection Event - January 15, 2008. 40 to 50 gallons of 10% sodium permanganate solution was injected into each of the three injection wells. These injections were followed by the injection of 10 to 50 gallons of water, depending on the points ability to "take" the water, to move the solution out into the surrounding area. 5). 5th Injection Event - January 15, 2008. 40 to 50 gallons of 10% sodium permanganate solution was injected into each of the three injection wells. These injections were followed by the injection of 10 to 50 gallons of water into each point, depending on the points ability to "take" the water, to move the solution out into the surrounding area.

Results to date:
Pre-injection contaminant levels: October 17, 2006 PCE - 19 mg/L TCE -.100 mg/L DCE -.790 mg/L VC - .001 mg/L Post injection contaminant levels: October 21, 2008 (Last sampling event) PCE - 2.7 mg/L TCE - .093 mg/L DCE - 1.9 mg/L VC - .067 mg/L

Next Steps:
Excavation of contaminated soil under the facility in the area of the former drycleaning machine.

Cost to Design and Implement:
$31,280.00