The company responsible for North Dakota’s largest pipeline spill suffered another leak on the same system one year after the first incident.
Meadowlark Midstream, a subsidiary of Summit Midstream, reported Friday 187 barrels, or 7,854 gallons, of saltwater leaked from the pipeline Thursday afternoon about 15 miles north of Williston, ND.
The spill occurred about 1½ miles south of where a pipeline leak ended up discovered almost exactly a year ago on the same saltwater pipeline system, said Bill Suess, spill investigation program manager with the North Dakota Department of Health.
In this case, the spill did not contaminate Blacktail Creek or any other surface water, Suess said. It’s still unknown if the latest spill contaminated groundwater, he said.
Health officials and the Oil and Gas Division are investigating. In this case, officials will take a close look at what’s going on to cause two leaks in the same system, Suess said.
“Anytime you have two releases from a single system, you’re going to have a concern,” Suess said.
On Jan. 6, 2015, the company discovered a pipeline leak adjacent to Blacktail Creek that involved an estimated 3 million gallons of brine. The contamination also reached the Little Muddy and Missouri rivers.
In that case, the North Dakota Industrial Commission said the pipeline was leaking for more than three months before anyone discovered it. An investigation is still ongoing.
That segment of pipeline ended up shut down since the discovery of the spill, said Alison Ritter, spokeswoman for the Department of Mineral Resources.
In the latest spill, crews were able to shut down the pipeline within 15 minutes of detecting a problem due to recent investments in leak monitoring and detection, said a spokesman for Meadowlark Midstream.
The spill occurred at 3:36 p.m. Thursday and they reported it to state officials at 3 p.m. Friday, just under the 24-hour deadline to report spills, Suess said.
Crews were excavating the contaminated soils on Friday and health officials were to visit the site Saturday. The pipeline remains shut down.
“The incident has been fully contained and Meadowlark is working cooperatively with the appropriate state agencies,” the company said.
Causes for both leaks are still under investigation. The Industrial Commission has proposed $2.4 million in fines to Summit Midstream for the 2015 spill, saying the pipeline likely began leaking on or before Oct. 1, 2014, or 98 days before anyone discovered it.
The Williams County Commission sent a letter to the Industrial Commission urging them to impose the entire fine, rather than their typical practice of suspending 75 percent to 90 percent of the fine.
The Environmental Protection Agency also is investigating Summit for the 2015 spill. The state health department plans to issue its own penalty for the 2015 spill, jointly with the EPA, but is waiting for an EPA criminal investigation to conclude, state health officials have said.