story by Ryan Saylor
rsaylor@thecitywire.com
Even though Whirlpools' final remedy work plan to clean up toxic, potentially cancer-causing trichloroethylene (TCE) has not yet been approved by the Arkansas Department of Environmental Quality, it has not stopped the company's environmental consultants from moving forward with at least one part of the proposal.
In an e-mail to ADEQ's Division Chief of Hazardous Waste Tammie Hynum, Principal Consultant Greg Gillespie of ENVIRON Corporation said Whirlpool would like for soil vapor monitoring to begin, even before waiting for approval of the final remedy work plan.
"As we discussed during our call last week, Whirlpool would like implement the additional soil gas work defined by the July 16, 2013 Work Plan," he said. "As requested attached is a letter with the relevant section of the work plan included for you to review / approve."
The letter explained that the work would be conducted in the offsite residential area north of Ingersoll Avenue.
"As we discussed during our phone conversation Aug. 1, 2013, the July 16, 2013, Final Remedy Work Plan (Work Plan) submitted by ENVIRON on behalf of Whirlpool presented activities to collect additional soil gas data in the offsite residential area north of Ingersoll Avenue to further substantiate there is no unacceptable risk from vapor intrusion at the site," the letter read.
Gillespie also said the work would "commence independent of the Revised Risk Management Plan (RRMP) and Work Plan currently being reviewed by ADEQ."
In the request to begin off-site soil vapor monitoring, Whirlpool's environmental consultants say that while their data backs up the company's claims that dangerous levels of TCE have not been found in the soil vapor, "Whirlpool concluded that additional soil gas monitoring points should be installed in order to enhance coverage of the off-site plume."
The company said in the letter that it would work with ADEQ to determine locations for the monitoring sites based on two criteria:
1. Proximity to existing off-site groundwater monitoring wells with higher concentrations of TCE; and
2. Proximity to an occupied residential building.
"The idea is to install additional soil gas monitoring points at locations that have higher potential for vapor intrusion to occur compared with other locations in the area," Gillespie said.
If TCE is found at dangerous levels in the soil vapors, he said additional "investigation" would be proposed to ADEQ.
"Such additional investigation may include the collection of sub-slab soil gas samples from under existing residences with concrete slabs. The sub-slab soil gas samples would be used to determine if the vapor intrusion pathway from groundwater actually extends to a particular building foundation and presents a potential for significant soil gas entry through the slab. If the targeted sub slab sampling indicates potential for vapor intrusion into the residence, indoor air data will then be collected."
In the letter, Gillespie claimed that false positives can occur with indoor testing as a result of household items that he said contain TCE as an active ingredient. He said items, including lubricants, adhesives, adhesive removers, automotive and household cleaners, aerosol and liquid spot removers, oven cleaners, silicone lubricants and aerosol gun cleaners all could contain TCE.
"Because of such indoor sources, it is not unusual to find measurable levels of TCE in residential indoor air even when no vapor intrusion is occurring."
In order to prevent impacts from possible indoor sources of TCE, Gillespie said the "industry standard" of gathering of sub-slab soil gas data would be the most effective way to collect the needed information.
A decision by ADEQ on Whirlpool's request has not yet been announced.