Holmesville Manufacturing Facility
This 59-acre site was used to manufacture a cleaning solvent for cleaning mimeograph machine rollers. The solvent was a mixture of PCE and high purity naphtha.
A mixture of naphtha and PCE was discovered floating on the groundwater surface, covering an area over 120 ft by 200 ft and averaging over 3 inches in thickness. Through a series of free product recovery wells, the free product was removed over a four year period by dual phase extraction and manual bailing.
The 300,000-square foot building is surrounded by agricultural or open land.
Concurrent with soil vapor extraction (SVE) operations, two rounds of EZVI injections into the shallow groundwater (20 to 30 ft below ground surface) were conducted:
- March 2006: Upgradient portion of source area (9,500 lbs EZVI)
- December 2007: Downgradient portion of source area (32,000 lbs EZVI)
Recovery wells were used for free product removal, then converted to soil vapor extraction to address smear zone contamination.
Source Area Results:
- PCE: 99% decline in source area
- Overall source contamination (PCE, TCE, c-DCE, VC): 95% decline by 2014
- Evidence of continuing anaerobic degradation
Downgradient Well MW-7sr:
- PCE was near 100 mg/L (two-thirds saturation limit) until early 2008
- c-DCE spiked over 500 mg/L shortly after first EZVI injections
- PCE and TCE: 99.6% decline since EZVI injections
- Steady, rapid decline from 2008 onward