MIDDLEPORT — The state Department of Environmental Conservation this week published its arsenic cleanup plan for certain non-residential land areas near the FMC Corporation's plant in the village. The estimated cost of the cleanup is $14 million.
The state's "Final Statement of Basis" for the FMC Corporation site, Air Deposition Area 2, Operable Unit 3 (OU#), directs the removal of an estimated 57,000 cubic yards of arsenic-tainted soil on strips of land immediately north and south of the Erie Canal and east of the Niagara-Orleans county line. The areas are comprised of Erie Canal Towpath, agricultural lands, railroad right-of-way and undeveloped lands.
The cleanup plan calls for excavation of contaminated soils and replacement with locally derived clean soils, along with post-construction monitoring. The goal of remediation is to drive down arsenic levels in the soils to 20 parts per million, from current concentrations up to 49 ppm, according to the DEC. Prior investigation showed the depths of contamination range from 0 to 12 inches below the ground surface.
The state's plan for OU3 includes a pilot study to test whether soil tilling and blending can work to drive down arsenic levels in lieu of excavation. The experiment will be attempted on larger parcels in the operating unit, DEC said.
The Final Statement of Basis for OU3 includes a section showing public comments and questions about the cleanup proposal and DEC's responses. Much of the public feedback, including a series of questions and concerns posed by FMC itself, was focused on the 20 ppm cleanup standard — some questioned whether that's too rigorous for non-residential property — and the possibility that soil excavation could upend wildlife habitat. OU3 includes grassy areas and a vacant wooded lot.
In its responses, DEC stated that its cleanup plan incorporates "green remediation" practices. Regarding trees, the agency said, the plan allows for the preservation of mature trees and "reasonable replacement" of those that have to be removed; it also requires implementation of a "tree preservation plan" that employs, for example, excavation methods that minimize damage to tree root systems.
In response to FMC's question about the 20 ppm standard, DEC said, "Regarding ecological resources, the soil cleanup objective (SCO) established for arsenic for protection of ecological resources (all flora and fauna and the habitats that support them) is 13 ppm. However, in this case, based on the site‐specific background, the cleanup goal is set higher at 20 ppm. Remediating the Middleport area to background will provide a long‐term benefit to all ecological resources, rather than leaving the higher levels of arsenic in place."
The cleanup bill will be paid by FMC Corporation per a 2019 settlement with the state. The local plant manufactured pesticides and herbicides from 1920s into the 1980s, during which time arsenic was released from the plant and settled in soils in the area. DEC considers man-made arsenic to be carcinogenic and a hazardous waste.
Cleanup documents can be viewed online at https:www.dec.ny.gov/data/DecDocs/932014/. Hard copies are kept by Royalton Hartland Community Library.