PALERMO WELL FIELD GROUNDWATER CONTAMINATION WASHINGTON EPA ID# WA0000026534

EPA Region 10 Thurston County Tumwater 3rd Congressional District Other Names:

Last Update: August, 2007

Site Description

The Palermo Well Field Groundwater Contamination site is located in a light commercial and residential area in the City of Tumwater. The site is surrounded by single family dwellings, private businesses, and recreational facilities. The Palermo Well Field consists of six water supply wells that provide up to 50% of the drinking water for the city of Tumwater. In 1993, routine sampling revealed the presence of trichloroethylene (TCE) in three of the six wells. The impacted wells were removed from service in 1993. Groundwater contamination at this site could potentially affect approximately 13,000-25,000 people.

Site Responsibility: This site is being addressed through federal actions.

NPL Listing History	Dates
Proposed Date:	12/23/1996
Removed Date:
Withdrawal Date:
Final Date:	04/01/1997
Deleted Date:

Threats and Contaminants

Media Affected: Soil, Surface Water & Groundwater
Groundwater and off-site surface water are contaminated with TCE and tetrachloroethylene (PCE). The source of PCE was determined to be a dry cleaning facility in the commercial area. Sources of TCE contamination include both former and current Washington Department of Transportation facilities in the commercial area. The contaminated groundwater represents a health risk to people using the aquifer as a domestic water supply. Contaminated groundwater surfacing in a residential neighborhood adjacent to the well field represents a potential health risk to people living in affected homes.


Cleanup Progress

Early Actions: A soil vapor extraction system was installed under the dry cleaning facility in early 1998 and operated until the summer of 2000. The extraction system removed approximately 400 pounds of PCE from the soils. Construction of two air stripping towers at the city wellfield was completed in March 1999. The treatment system is removing contaminants from the groundwater to non-detectable levels and has allowed the city to use all six wells for its water supply.

Long-term Actions: EPA completed a Remedial Investigation and Feasibility Study in June 1999 and determined the final cleanup remedy for the site in November 1999. This remedy was completed in February 2001. In addition to the early actions, the final cleanup includes construction of an underground drainage system to lower the groundwater table under the affected homes. The contaminated water collected by the drainage system is treated in an aerated lagoon before discharging into an existing drainage ditch, which flows into the Deschutes River. After closely monitoring the effectiveness of the drainage system, EPA determined that the system was operational and functional and turned over operation and maintenance responsibilities to the State of Washington and City of Tumwater. During this project, EPA has worked to keep the community closely informed and involved, scheduling site visits, holding several public informational meetings and a public hearing, and sending out informational fact sheets. While the drain was being built, EPA staff and contractors met with the community regularly to ensure that construction went smoothly and their concerns were addressed.
EPA completed a Five-Year Review of the remedy in September 2003. The most significant outcome of the review was that the underground drainage system may not be adequately protecting all residences in the Palermo residential area and that additional assessment is needed. The main reasons for the additional assessment are new information indicating that PCE & TCE may be more toxic than previously believed and the groundwater table has not been consistently lowered as designed. EPA conducts monitoring of the air in crawlspaces of houses above TCE contaminated groundwater. EPA is assessing whether it would be more appropriate to install mitigation systems to prevent inhalation of TCE from the crawl spaces. EPA litigated against Washington Department of Transportation in 2007. The court found Washington Department of Transportation liable for the TCE contamination.


Regional Contacts

SITE MANAGER(S):	Chris Cora
E-MAIL ADDRESS:	cora.christopher@epa.gov
PHONE NUMBER:	206-553-1478
COMMUNITY INVOLVEMENT COORDINATOR:	Charles Bert
E-MAIL ADDRESS	bert.charles@epa.gov
PHONE NUMBER:	360-753-8073

Information pertaining to this site is housed at the following location(s):
Tumwater Public Library (Administrative Records)
7023 New Market Street
Tumwater, WA 98501

EPA Region 10 Superfund Records Center (Administrative Records)
1200 Sixth Avenue, ECL-076
Seattle, WA 98101