The fine was requested by federal prosecutors in a plea agreement filed earlier this month in US District Court.
FX also agreed to plead guilty to federal criminal charges of violating the US Clean Water Act. In exchange, prosecutors dropped related charges against FX field supervisor Quay Geza Torok.
The company had previously said it had not broken any laws.
According to court documents, Torok discovered that an underground flow line had ruptured at the company's Southwest Cut Bank Sand Unit on the Blackfeet Indian Reservation in Montana in June 2011.
He
