The lawsuit alleges coal and petroleum coke fall daily from UBT’s conveyor belts at Davant, landing both in the river and on its bank.

UBT denied the allegations and released a statement saying it put substantial time and money into complying with air and water permits.

The environmentalists claimed UBT ignored state law, which requires immediate clean-up of spilled materials.

The groups are seeking fines against UBT under the federal Clean Water Act as well as orders for it to clean the river and river bank.