Where does the groundwater go? GE proposes final PCB landfill plan for Massachusetts River

“After soil dredged from the Housatonic River and its banks is gathered and stored in a nearby landfill, what will happen to water that comes in contact with that PCB-contaminated material?

That water from river sediments and storms, known as leachate, will be collected and trucked to General Electric’s treatment plant in Pittsfield, according to the company’s final design plan for the landfill, also known as the Upland Disposal Facility.

The proposal, submitted to the U.S. Environmental Protection Agency on Wednesday, outlines plans for the landfill on Woodland Road. The former gravel quarry, now owned by GE, will hold sediments with average PCB concentrations below 50 parts per million.

Public comment on the proposal, which is 1,374 PDF pages long and includes data tables, design drawings and maps, is being accepted through May 3. Comments should be sent to [email protected].

The landfill, approved through a closed-door negotiation process, is a key element of the Rest of River cleanup permit approved by EPA in 2020. A previous cleanup permit, approved in 2016, required GE to transport all sediments out of the area.

The plan, outlines the design and operational plan for a landfill with a capacity of 1.3 million cubic yards in a former gravel quarry off Woodland Road.

The plan proposes a trapezoidal-shaped consolidation area — the space where the contaminated sediments will be buried — of 13 acres in two cells. It would be surrounded by an elevated berm, and capped once disposal is complete.

The proposal also states that the design meets a performance standard of sitting 15 feet above the highest seasonal groundwater level.

GE used PCBs in manufacturing power transformers until the 1970s, when the chemical was banned as a probable cause of cancer.

A consent decree between GE, the city of Pittsfield and federal and state regulators in 2000 set the framework for removing PCBs from GE’s 254-acre campus and the Housatonic River. The first mile and a half of the river from the GE plant to Fred Garner River Park has already been remediated.

Environmental advocates and plan opponents have said the location of the landfill is a poor choice because of its proximity to the river and October Mountain State Forest, its position above a significant groundwater aquifer, and concerns that a landfill failure would result in contamination returning to the Housatonic.

Dean Tagliaferro, who is EPA’s project manager, has previously voiced confidence that the design, which includes five layers of protective liners, and the location, which makes it possible to siphon contaminants directly from the Woods Pond dam, will serve the long-held goal of removing PCBs from the river.

“It all can be done safely and the goal is the long-term goal: Make the river a usable asset that reduces the risk to public health,” he said during a tour of the site last fall. “That’s the metric: reduce risk and make it reusable.”’