THIN LAYER CAPPING

Thin Layer Cap Pilot Construction to Begin in August 2026

The $50 million cleanup of mercury contamination in Orrington kicks off in August with a small-scale capping pilot project in East Cove 3.

The Thin Layer Cap (TLC) Pilot project's goal is to test if capping effectively reduces exposure to mercury in intertidal flat sediments and to show that protected natural resources will recover.

The capping will place 4 to 6 inches of clean sand on ±6 acres of contaminated intertidal sediments adjacent to the Orrington Picnic Park. Capping is expected to start by mid-August and take up to 4 weeks to complete.

Preparations—including trucks hauling sand to the staging area off State Route 15 (River Road)—are slated to begin in July.

Cap performance and ecosystem impacts will be monitored for 3 to 5 years after construction.

The results will be used to evaluate the feasibility of full-scale capping of intertidal flats in coves between Orrington and North Bucksport.

The work is being managed by Greenfield Penobscot Estuary Remediation Trust LLC—the court-approved Trustee of the Penobscot Estuary Mercury Remediation Trust (Remediation Trust).

CAPPING NEAR ORRINGTON PICNIC PARK

Visit the riverfront Orrington Picnic Park located off State Route 15 (River Road) about a mile south of Center Drive in Orrington to learn about the capping.

View capping
Visit our kiosk for more capping information
Talk to Remediation Trust representatives on a date to be announced on this webpage and on our hotline. Weather dependent.

STAY INFORMED