CHARLOTTE (AP) — North Carolina environmental officials say they’re fining Duke Energy $25 million over pollution that has been seeping into groundwater for years from a pair of coal ash pits at a retired power plant.

The state environmental department issued the fine Tuesday over ongoing contamination at the L.V. Sutton Electric Plant outside Wilmington. The site includes a pair of unlined dumps estimated to hold 2.6 million tons of ash.

The department’s director, Donald van der Vaart, says the state wants to hold Duke accountable for years of pollution.

The department says monitoring wells near Duke’s dumps at Sutton showed readings exceeding state groundwater standards for several toxic chemicals.

Charlotte-based Duke Energy has 30 days to appeal the fine.

The company did not immediately respond to email or phone messages.