Publication Summary

Groundwater samples for volatile organic analysis were collected from eight monitoring wells quarterly from July 2002 through April 2003 at Shelton Laundry and Cleaners in Shelton, Washington. Samples were collected to determine the current concentrations and distribution of tetrachloroethylene (PCE).

Groundwater samples for volatile organic analysis were collected from eight monitoring wells quarterly from July 2002 through April 2003 at Shelton Laundry and Cleaners in Shelton, Washington. Samples were collected to determine the current concentrations and distribution of tetrachloroethylene (PCE). PCE contamination of the shallow groundwater was discovered in 1997 during an environmental site assessment of a nearby property. The source of the contamination was assumed to be a spill that occurred in 1993 at the dry cleaning facility occupied by Shelton Laundry and Cleaners.

Monitoring of four shallow wells installed in 1998 detected PCE contamination in the well (4W) located where the spill was reported to have occurred, with concentrations ranging from 280 ug/L (July 1998) to 25 ug/L (September 2000). Four additional deeper wells were installed in 2002. Results from the most recent monitoring concur with previous results. PCE was primarily detected in well 4W. PCE concentrations in this well ranged from 9 to 17 ug/L. Trichloroethylene and cis-1,2-dichloroethylene also were detected in 4W, but at concentrations near or below the practical quantitation limit of 1 ug/L. PCE was not detected in any of the four deeper wells.

Although contaminant concentrations have decreased since 1998, PCE concentrations in well 4W exceeded the Model Toxic Control Act cleanup standard of 5.0 ug/L. Because PCE concentrations continue to exceed the cleanup standards in this well, some level of monitoring should continue. Additional investigation or possible remedial action also could be considered to further reduce PCE concentrations at this site.

Link to EIM data for User Study ID PMAR0001