Publication Summary

Groundwater samples for volatile organics were collected from four monitoring wells in September 2004 and April 2005 at Shelton Laundry and Cleaners. Samples were collected to monitor concentrations of tetrachloroethylene (PCE) from a spill that occurred in 1993. PCE was detected in well 4W at concentrations of 9.9 and 20 ug/L, which exceed the Model Toxic Control Act cleanup standard of 5 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 the two deep wells that were sampled.

Groundwater samples for volatile organic analysis were collected from two shallow and two deep monitoring wells during September 2004 and April 2005 at Shelton Laundry and Cleaners in Shelton, Washington. Samples were collected to monitor 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 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 well 4W, located where the spill was reported to have occurred, with concentrations ranging from 280 ug/L in July 1998 to 25 ug/L in September 2000. In 2002, four additional deeper wells were installed. Results from the 2002 monitoring indicated that PCE contamination occured at well 4W with an average concentration of 13 ug/L. PCE was not detected in the four deep wells.

Results from the September 2004 and April 2005 monitoring concur with previous results. PCE was detected in well 4W with concentrations of 9.9 to 20 ug/L. Trichloroethylene and cis-1,2-dichloroethylene also were detected in well 4W but at concentrations near or below the practical quantitation limit of 1 ug/L. PCE was not detected in the two 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 standard in well 4W, a remedial action was implemented at this well in June 2005. Groundwater monitoring will continue on a quarterly basis for the next year to determine if the remediation has been effective.

Link to EIM data for User Study ID PMART001