9,400 tons of court-ordered sand to be deposited in Penobscot River this summer

BANGOR DAILY NEWS • May 28, 2026

A pilot project depositing about 9,400 tons of sand in the lower Penobscot River to test its effectiveness in covering mercury contamination is likely to begin in mid-August. The project is a court-ordered step, years in the making, toward addressing industrial mercury contamination in the estuary that has had wide-reaching negative effects throughout the food chain and on human uses of the waterway. If successful, the method will likely be used to cap an additional 124 acres of intertidal flats. The mercury contamination stemmed from the now-defunct HoltraChem plant in Orrington, which illegally discharged between 6 and 12 tons of the toxic metal in the river in the late 1960s and early ’70s.