The Meeker Avenue Plume has been a designated federal Superfund site for two years, and earlier this month, the U.S. Environmental Protection Agency shared some of their initial findings as well as a planned proposal for site evaluation, protection, and cleanup during a public meeting at St. Stanislaus Kostka Lower Church.
Trichloroethylene (TCE) and Tetrachloroethylene (PCE) have been identified as the main contaminants of concern, which the EPA considers both linked to cancer and neurological diseases, with low levels of TCE exposure in pregnant women also increasing the risk of cardiac birth defects. In this case, the contaminants were determined through sampling soil vapor and indoor air concentrations of properties determined to have “high-end exposure conditions.”
As part of their mitigation efforts, the EPA has identified over 1,000 properties within their site study area that may be impacted. Factors like building conditions and the level of contamination beneath and near the structure can affect the likelihood of vapor intrusion; when contaminants are in the soil and groundwater, they can be released as gasses and sucked up into buildings, then dispersed throughout the air. The EPA has been conducting air sampling since late 2022, and presently have evaluated 18 residential structures, 11 public housing buildings, and one public school (none were found to need vapor mitigation, but monitoring should continue at residences), plus 18 additional properties this spring.
The objectives being put forth by the proposed plan include preventing the exposure of related PCE and TCE vapors within structures to current and future occupants and preventing the migration of contaminated sub-surface vapors into indoor air of structures to avoid threats to human health. The proposed remediation would involve actions like sealing cracks and gaps in slabs, installing additional slabs to replace dirt floors, and installing sub-slab depressurization
mitigation systems — effectively a type of fan designed to reverse or alter the direction of soil gas flow (therefore directing it away from homes). This work is estimated to take five years and cost $1,145,200.
The EPA’s document also shared that the New York State Department of Environmental Conservation already identified 26 properties that required the aforementioned sub-slab depressurization systems and two in need of gap sealing before the Superfund distinction was made.
The full proposal is available here and the public comment period is open until May 10; written comments can be directed to Rupika Ketu at ketu.rupika@epa.gov or by mail at the below address:
Rupika Ketu
Remedial Project Manager
U.S. Environmental Protection Agency
290 Broadway, 18th Floor
New York, NY 10007