Source: The Chronicle (Centralia, WA), May 10, 2014
Posted on: http://envfpn.advisen.com
The cleanup process for a hazardous waste site just south of Chehalis will begin next month.
The U.S. Environmental Protection Agency will start sampling groundwater June 11 at the Hamilton/Labree Superfund site near North Hamilton Road west of Interstate 5 to pinpoint where the contaminated groundwater is most prevalent.
Once the contamination is identified, cleanup will likely begin next summer, Project Manager Tamara Langton said.
“What is coming up now is we are doing a bunch of sampling with a bunch of drill rigs to better categorize where the hottest contamination is, so when we start clean up with a thermal treatment and injections of biological stuff we will know the best places to put it,” Langton said.
The cleanup will be focused on a 10-acre portion of the Superfund site called the Hamilton Road Impact Area.
The EPA will use thermal heat treatment on the contaminated soils and a biological treatment to break down and remove the contaminant tetrachloroethene, known as PCE, from the groundwater.
PCE is a chemical used for dry cleaning, metal degreasing and other industrial processes.
The Washington State Health Department first found contamination at the site in 1993. It came from a spill or direct release of 100 to 700 gallons of liquid PCE into Berwick Creek aquifer.
Langton said the thermal treatment will reach 190.4 degrees, the boiling point for PCE. Thermal treatments typically takes one to two months to heat up followed by four to six months of treatment time.
The biological treatment will then inject a liquid, similar to vegetable oil, into the ground to help the growth of bacteria and insects that eat away at the PCE.
“It creates a condition in the groundwater where the bacteria and bugs like to live and they will often eat and destroy the contamination,” Langton said. “The area doesn’t really have that. We need to enhance it a bit.”
The cleanup plan will also re-route Berwick Creek around the contamination areas to help protect fish and animals from possible negative impacts caused by cleanup activities.
Last summer, the EPA approved the clean up plan for the Hamilton Road Impact Area. However, Langton said the EPA will need about $11 million in federal money to fund the cleanup. She anticipates the funding coming through this fall, with cleanup beginning next summer.
“It would be great if we could to get the clean up started in the summer of 2015. I’ll know more this fall or winter about the (funding),” Langton said. “This particular project dragged on for years, but it’s pretty much on pace since we put the proposed plan out.”
The EPA tested water from 19 wells last spring on properties along Rice and Hamilton Roads and found the PCE had not migrated downstream of the Superfund site.
Many homes and businesses near the site are now using drinking water from the city of Chehalis public water supply system. No one is currently drinking contaminated water. However, if the PCE is not cleaned up and continues to move down the valley, residents not on the Chehalis water system may be at risk, according to the EPA.
“That is why last year I wanted to double check those homes that were above and below to show they were still okay drinking their well water and they were,” Langton said.
PCE is a carcinogen and can cause kidney problems and neurological issues, Langton said.
Drinking large amounts of PCE can cause dizziness, headache, sleepiness, confusion, nausea, difficulty in speaking and walking, unconsciousness and death, according to the U.S. Center for Disease Control and Prevention.
The exact date of the PCE spill or release is unknown but likely occurred before 1990, according to an EPA report.
In 1999, the EPA found 64 drums of PCE buried under a building owned by the S.C. Breen Construction Co. The barrels were removed and disposed of as hazardous waste.
The S.C. Breen company signed an order as a “potentially liable party.” It has paid for testing and studies of how to clean up the area.
Langton said there were never any charges for the contamination of the now Superfund site.
The EPA and Washington State Department of Ecology conducted an investigation, but the source of the contamination was never found.
Langton said the EPA is working with S.C. Breen and seeking more funding to finish cleaning up the other portions of the Superfund site. There is not timeline for the entire Superfund site cleanup.
“We have certain areas where we would like to focus our next investigations on,” Langton said. “We are using a phased approached to see what the impacts are while cleaning up the portions.”