By Dustin Monke and Amy Dalrymple
WHITE EARTH, N.D. — The amount of oil and brine recovered from an oil well near the White Earth River reached 756,000 gallons Tuesday, though officials said 99.9 percent of the contamination was contained to the well pad.
An estimated 18,000 barrels of oil and brine water has been recovered so far, but the total amount spilled is still under investigation, said Department of Mineral Resources spokeswoman Alison Ritter.
“It’s a moving target,” Ritter said.
The Mountrail County well owned by Oasis Petroleum began releasing uncontrollably about 11 p.m. Saturday and remained out of control until crews shut it down just before 11 a.m. Tuesday. The well is less than 1,000 feet from the White Earth River.
The cause of the well control incident is under investigation, but preliminary information shows that a leak on a surface pipe likely failed, Oasis Petroleum said in a statement.
Bill Suess, spill investigations program manager for the North Dakota Department of Health, said 99.9 percent of the contamination stayed on the well pad. Some contamination misted off the location, causing a sheen on the White Earth River, a tributary to Lake Sakakawea and the Missouri River, the primary drinking water source for southwest North Dakota.
Oasis placed 49 absorbent booms across the White Earth River since discovering the spill late Saturday night.
“The river is doing good. We’ve been up there, we’ve been monitoring the river,” Suess said. “We’ve seen no detection of impacts beyond that first set of booms. … We saw the sheen Sunday, but no sheen was visible (Monday).”
The oil sheen on the river was likely caused by airborne oil that sprayed away from the
A 40-acre vegetated area off the well pad was also “lightly sprayed” by the oil and brine
water mix, Suess said, and only accounted for a few barrels of what was released from the well.
While oil can be recovered from water with the absorbent booms, Suess said tracking the
brine water impact is trickier. Brine water is a highly concentrated water solution, often referred to as saltwater.
“You have to pretty much let it dilute and dissipate,” he said.
The Department of Health has been doing chloride testing along the White Earth River and at the mouth of the river, where it meets Lake Sakakawea.
“We’ve been collecting samples and running lab analysis that’ll give us a more detailed look,” Suess said. “The initial chloride testing we’ve been doing on site shows no impact of brine.”
No impacts to wildlife have been detected, Suess said.
It’s too early in the investigation to comment on whether Oasis will face penalties for the incident, Ritter said.
“These uncontrolled situations are some of the more serious of environmental incidents,” Ritter said.
Oasis was penalized $76,500 by the North Dakota Industrial Commission in May for a November 2014 well control incident. The company paid $16,500 and the Industrial Commission suspended $60,000 in fines for one year with the requirement that the company not commit any “same or substantially similar” violations.
It’s yet to be determined if the latest incident will be considered substantially similar to the 2014 incident, Ritter said. The 2014 incident occurred while the well was being fracked and the wellhead separated from the casing, causing the uncontrolled release.
In addition, the same well involved in this latest spill, known as Helling Trust 11-15H, also had a spill of 190 barrels, or 7,980 gallons, of oil and brine in January that was caused by a tank overflow, according to the North Dakota Department of Health. The spill was contained within the dikes of the well pad and recovered.