LEE — The cleanup of the Housatonic River enters a critical phase in 2026, as General Electric prepares to begin construction on a Lee landfill that will house millions of cubic yards of PCB-contaminated sediment.

General Electric Co. hopes to begin construction by late spring on the controversial disposal site in Lee, where up to 1.3 million cubic yards of sediments will be deposited before the landfill is capped in 2038.

The cleanup stems from a 2000 consent decree that ordered General Electric to remediate the affected areas of the Housatonic River after the company disposed of PCBs, a chemical suspected to cause cancer in humans, in the river during decades of manufacturing in Pittsfield. The Lee landfill site will house sediments contaminated with lower concentrations of PCBs.

Site clearing preparations began in early November, 2025, at the future landfill site, a former quarry located off Woodland Road. Once complete, the landfill will span about 13 acres.

“Pre-construction activities at the [Upland Disposal Facility], which include tree clearing, establishment of a construction entrance and fence construction, are nearly complete,” Bill Callen, a spokesman for General Electric, wrote in an email to The Eagle.

General Electric must now submit a site plan to the Environmental Protection Agency by Feb. 18 that contains detailed information about the project, including travel routes for utility vehicles and a proposed construction schedule.

While detailed information about the construction timeline will not be available until the site plan is public, Jo Anne Kittrell, a spokeswoman for EPA, said that “significant earthwork, such as landscape contouring and moving soil, will need to occur prior to beginning liner installation.”

A 45-day public comment period will follow the site plan’s publication, after which EPA will decide whether to approve the project and permit construction to begin. Construction on the landfill itself is expected to continue into 2028, followed by a decade of sediment and soil deposits before the landfill is capped in 2038.

Air quality and noise levels during site clearing are currently being monitored, with readings available at the Housatonic River Project website. Monitoring of the project’s environmental data will continue during construction itself.

Lee’s PCB Advisory Committee will meet next on Jan. 27 to discuss the progress of the project.