MANDAREE, N.D. – The Environmental Protection Agency is investigating whether Crestwood Midstream violated the Clean Water Act last year when a pipeline spill leaked about 1 million gallons of brine on the Fort Berthold Indian Reservation.
The EPA has issued Crestwood Midstream and Arrow Pipeline a Notice of Potential Violation for the July 2014 pipeline spill near Mandaree.
The notice states that the brine flowed in a stormwater ditch and then a ravine before entering an unnamed tributary and traveling about a mile north through a series of beaver dams before reaching Bear Den Bay of Lake Sakakawea. Lake Sakakawea and its tributaries are waters of the United States.
The EPA has not made a final determination.
Crestwood Midstream also received a grand jury subpoena this year regarding the spill from the North Dakota U.S. Attorney’s Office, according to notes to financial statements Crestwood filed with the Securities and Exchange Commission this month.
Chris Myers, acting U.S. attorney, did not return calls seeking comment.
The company reported two other smaller pipeline spills last year, totaling about 168,000 gallons of brine, as well as another pipeline spill reported May 7 near Mandaree. The tribe has estimated the latest spill at 220,000 gallons, but the spill report to the North Dakota Department of Health included an estimate of up to 336,000 gallons.
Crestwood Midstream did not respond to a request for comment.
Lynn Helms, director of the North Dakota Department of Mineral Resources, commented on the Crestwood saltwater gathering system last week during his monthly update on oil production, saying the system has “substantial problems.”
Helms said the pipeline system was installed in 2010, prior to new rules taking effect that allow the state to regulate gathering pipelines. Because the pipeline is at Fort Berthold, it falls under the jurisdiction of multiple agencies and the Three Affiliated Tribes environmental division has taken the lead on it, Helms said.
Edmund Baker, environmental director for the Three Affiliated Tribes, did not return a call seeking comment.