A plan to clean up the former Medfield State Hospital site, contaminated by a decades-old oil spill and construction debris, is moving forward after town officials gave their blessing for the project last week.
The Board of Selectmen on Tuesday unanimously approved the state Division of Capital Asset Management and Maintenance’s conceptual plan, which could take 18 months to complete. The plan calls for the cleanup of 3.2 acres on the hospital site contaminated by construction and disposal debris, and of an 1,800-square-foot area alongside the Charles River with sediment remaining from the 1978 oil spill.
The plan also calls for demolition of three buildings — the laundry, the Odyssey House, and the Carriage House — at the former state hospital, which has been closed since 2003.
The project’s cost has been estimated at $8.5 million.
The state first presented the plan to the public at a meeting June 6. However, it is not the first time the state has proposed a cleanup plan of the site.
A 2011 plan drew opposition from town officials, watershed organizations, and residents, leading to the town’s request for mediation to help draft an acceptable proposal.
The new plan is a result of the state and town working together to focus to find the best outcome for the site.
Following Tuesday’s approval by selectmen, the next step is the permitting phase, said Assistant Town Manager Kristine Trierweiler. During the June 6 public meeting, officials said that as the design process moves forward, residents will have an opportunity to add input.
The plan includes moving excavated debris uphill, away from the river, into a sealed and capped disposal area, restoring wetlands and meadows, and reconnecting the property to the Bay Circuit Trail. A canoe launching area on the river is also planned.
The Charles River Watershed Association calls the new plan a “significant departure from the initial plan’’ in 2011.
“This is a winning solution that will protect the Charles and restore this beautiful stretch of riverfront,” said Margaret Van Deusen, deputy director and general counsel for the association. “This cleanup will serve as a model for the future remediation of contaminated state lands along waterways.”