TROY — Representatives from the U.S. Environmental Protection Agency presented a plan to address the East Troy contaminated aquifer site on Wednesday.
The meeting was held at City Hall and more than 50 residents attended. The presentation is part of the public comment period before a final decision is made for a cleanup plan begins. The funding for the cleanup would be from federal EPA funds with total estimated clean-up cost projected to be $19.7 million.
The proposed interim cleanup plan includes soil excavation with off-site disposal for the East Water Street Soil Source area and for the residential plume source area a treatment using chemical oxidation and installation of sub-slab depressurization systems.
The two contaminated sites are located in the dock area of the former Hobart Cabinet Company and the former site of a Waltz Cleaners dry cleaning business. The EPA has studied the site which consists of groundwater contaminated with chlorinated volatile organic compounds which includes trichloroethene (TCE) and tetrachlorethene (PCE). These chemicals have been found in the site’s groundwater, soil and in indoor air within buildings located about the contaminated underground water in the site.
“The water is safe. Everyone is getting their drinking water from the city’s water supply. A lot of the risks we are talking about is if you drink the contaminated ground water,” said Shari Kolak, EPA remedial project manager. For example, if someone was to drink water from a well in the area, it would contain contaminated ground water where as the city’s water source is treated from its aquifers and its 24-hour 365 days a year monitored well systems.
The U.S. EPA’s recommendations is for the excavation of impacted soil at specific areas at the former Hobart Cabinet Company’s dock area and Spinnaker parking lot with off site disposal. According to the report, the contaminated soil would be removed and transported to an off-site licensed landfill for disposal and then back-filled with gravel or clean soil. No long term operations and maintenance or institutional controls would be needed for the excavated areas. The estimated cost is $2.3 million and would take three months to complete.
The second recommendation is to inject oxygen-containing chemicals into the groundwater to help reduce contaminant concentrations and throughout “the plume” area. Clean groundwater would be pumped from a new water supply well (located outside the plume) and processed. Remediation goals “are expected to be achieved within 10 years of commencement of groundwater remediation.” The estimated cost for the recommendation is $12 million and would take one year to construct.
The third recommendation would to install residential area sub-slab depressurization systems (SSD) and performance monitoring. The EPA would install SSD systems at all homes and business above (TCE) the targeted groundwater treatment area (walnut to Union Street) and in the three-block buffer area (Union to Frank Street). The systems are similar to radon mitigation systems. The EPA estimates 156 properties, 28 of which are commercial properties, would be offered the SSD systems. The SSD would actively remove soil vapors from beneath the building’s slab to reduce the potential for vapor intrusion. The estimated cost is $5.4 million and take six days per home including pre-installation inspection, installation and testing.
Residents can access the presentation online at the city of Troy’s YouTube channel or at www.epa.gov/superfund/east-troy-aquifer
PUBLIC COMMENTS REQUESTED
U.S. Environmental Protection Agency (EPA) is taking public comment on the proposed interim cleanup plan for two contaminated source areas associated with the East Troy Contaminated Aquifer Superfund site in Troy.
EPA’s 30-day comment period begins June 25 and closes July 25. All comments will be considered before EPA makes its cleanup plan final. Comments can be:
• Submitted orally or in writing at the public meeting on Wednesday, June 27, at 6 p.m. at City Hall, 100 S. Market St. in Troy.
• Mailed to EPA Community Involvement Coordinator Adrian Palomeque at U.S. EPA Region 5 (SI-6J), 77 W. Jackson Blvd., Chicago, IL 60604-3590.
• Submitted online at: http://www.epa.gov/superfund/east-troy-aquifer.