EPA discovered the Highway 3 PCE Superfund Site in
April 2008, when tetrachloroethylene (PCE) was detected in groundwater samples
collected in the downtown area of Le Mars, Iowa, as part of an investigation of
the nearby Le Mars Coal Gasification Plant Site. PCE and its degradation products
detected in the groundwater samples were determined not to be associated with
the Le Mars Coal Gasification Plant Site. As a result, EPA created the Highway
3 PCE Site, encompassing the downtown area of Le Mars, and began follow-up
sampling to investigate the presence and source of PCE.
Since discovery of the site, EPA has conducted sampling
activities to better understand the extent of the contamination and the
potential risks to human health and the environment posed by it, and to develop
and implement a cleanup plan to address identified risks. PCE was detected at
levels above health concern in indoor air at buildings within the site area. As
a result, the EPA Superfund Program initiated a time-critical removal action on
Aug. 21, 2013, to install vapor intrusion mitigation systems in 20 buildings in
downtown Le Mars. The current planned removal action will address
PCE-contaminated soil.