WILLISTON The North Dakota Department of Health now says a saltwater leak in Williams County has released nearly 3 million gallons of the oil-field produced product into Blacktail Creek, making it the largest in state history.

“Probably the biggest we’ve ever seen. If it isn’t, it’s right up there,” said Dave Glatt, Department of Health. “We haven’t completed all the assessments but it has the potential to have significant impact.”

The spill was discovered Jan. 6 and reported to the Department of Health the following day. How long the brine was flowing from a ruptured 4-inch saltwater disposal pipeline is unknown. Truckers contracted to haul saltwater carried by the Summit Midstream pipeline sounded the alarm after finding the amount of saltwater to be hauled was much less than expected.

After thoroughly checking pipeline records and readings, Summit Midstream reported to the Department of Health late Tuesday that the size of the saltwater spill was “approximately 70,000 barrels”, or 2.9 million gallons. Produced water, or brine, is 10 to 30 times saltier than ocean water. It is regarded as toxic by the Department of Health.

“There are environmental issues that we’re concerned about,” said Glatt. “We’re not seeing any impact to public health but we don’t want any cattle or livestock drinking that water. I could be lethal.”

After arriving at the site, the Department of Health took water samples at 19 separate locations along the lengthy route of the spill that dumped into Blacktail Creek. Blacktail Creek joins the Little Muddy River which flows into the Missouri River and Lake Sakakawea. Water samples in the Little Muddy, an estimated 23 river miles downstream from the spill site, showed evidence of saltwater.

“It made it down as far as the Missouri and then dilutes out,” said Glatt.

According to Summit Midstream, which has offices in Stanley and Epping, the pipeline is operated by Meadowlark Midstream Co., a subsidiary of Summit Midstream Partners. Rene Casadaban, chief operating officer for Summit Midstream, in a release, said, “The company places paramount importance on its environmental and related responsibilities.”

The Department of Health says Summit Midstream has hired an environmental contractor to help with cleanup measures and long-term remediation. As of Tuesday, says the Department of Health, 64,000 barrels of water have been extracted from Blacktail Creek. However, says the Department of Health, the amount of water removed cannot be fully equated with the amount of saltwater spilled.

The Department of Health says it will continue to monitor the impacted area and the cleanup efforts.

“The important takeaway for me is that this is a significant spill,” stated Glatt. “The impact is there and we need to remedy that as quickly as possible.”

Due to a covering of ice on the Little Muddy River it is not possible to accurately assess the adverse impact of the spill. Saltwater kills both plants and aquatic animals. According to Glatt, further testing and examination will take place as soon as possible in the spring. Until then the Department of Health will continue to monitor water in Blacktail Creek and the Little Muddy.

The city of Williston draws its drinking water from a municipal intake structure upstream from where the Little Muddy enters the Missouri, thereby shielding citizens in that community from dealing with brine in their drinking water supply. However, a leak in an oil pipeline in the Yellowstone River near Glendive, Mont., may yet prove to be a cause for concern in Williston.

The Montana National Guard is currently trucking water into Glendive because the city’s water supply has been contaminated by the Yellowstone River oil spill. Residents of Glendive reported a smell similar to diesel fuel in their tap water. The city’s water treatment plant has ceased operating until a remedy can be found and the city’s water system decontaminated.

A sheen of oil was reported on the Yellowstone River near Sidney, Mont., Tuesday. Sidney is a community close to the Montana-North Dakota border. A representative of the Environmental Protection Agency is on scene and closely monitoring the impact of the spill which has the potential to reach North Dakota. If so, Williston’s municipal water intake could be at risk because the Yellowstone joins the Missouri upstream from the city’s intake system.

“As of Wednesday it had not reached North Dakota,” said Glatt when asked about the Yellowstone oil spill. “We’ll take water samples at the intake at Williston as a precaution this week and next week. We’ll keep an eye on what they are finding in Montana and potentially do more with the drinking water system.”