SCADA system could have detected leak before more damage was done in North Dakota.
A pipeline leak that spilled nearly 3 million gallons of salt water and contaminated a creek and two rivers near Williston, North Dakota, could have been prevented with the proper equipment.
According to the North Dakota Department of Mineral Resources, the pipeline could have been monitored remotely, but the system wasn’t turned on. Instead, Meadowlark Midstream relied on checking meters by hand rather than the sophisticated system that had been installed.
The department estimates that the pipeline was leaking for more than 12 days before the rupture was discovered on
Jan. 6.
MONITORING THE PIPELINES
The pipeline that ruptured was transporting produced water from 40 well pads to a saltwater disposal well north of Williston.
The pipelines were equipped with flowmeters, which could have been monitored through the offsite SCADA systems, but Meadowlark wasn’t using it.
“They had to drive out to the site, read the number on the meter, and then go site to site, read the numbers and sit down with a computer and add them up to try to see if there were differences that indicated a leak,” says Lynn Helms, director of the Department of Mineral Resources.
Meadowlark had done monthly flyover inspections of its pipeline as recently as Dec. 30, but there was no evidence of a leak at that time, Helms says.
State legislation being proposed would strengthen requirements for pipeline monitoring in North Dakota, but the state’s Industrial Commission does not currently require gathering pipelines to have meters or monitoring systems.
About 50,000 miles of pipeline is buried throughout North Dakota, carrying everything from oil and natural gas to salt water and freshwater.
“There is such a quagmire of jurisdictional responsibility for pipelines,” says Brian Kalk, North Dakota Public Service commissioner. “It’s a challenge when an incident occurs and who is responsible to do the investigation to see what happened.”
The Public Service Commission oversees the siting of transmission lines for natural gas and oil in the state, but only oversees the safety of the natural gas lines. The Office of Pipeline Safety within the U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration has regulatory responsibility for inspecting and enforcing pipeline safety regulations for interstate and intrastate pipelines carrying hazardous liquid in North Dakota, except for natural gas. The Department of Mineral Resources’ Oil and Gas Division has broad safety and siting jurisdiction over pipelines as part of its well-permitting process.
In February, the Department of Mineral Resources hired two pipeline inspectors, filling positions that had been vacant for months. The inspectors will oversee more than 20,000 miles of crude oil, water and other pipelines that fall under the department’s jurisdiction.
Under new legislation being proposed to strengthen safety, operators of the pipelines would have to hire certified third-party pipeline inspectors to inspect their work. One of the roles of the new state pipeline inspectors would be to “inspect the inspectors” and ensure that they’re
doing their jobs properly, Helms says.
By comparison, the state of Pennsylvania has six inspectors who are located across the state and on call 24 hours a day for emergencies. They check for compliance with state and federal gas pipeline safety regulations.
CLEANING THE SPILL
The pipeline rupture released about 70,000 barrels of produced water, the largest spill of its kind in North Dakota. The brine — which can contain oil, fracking fluid and other chemical compounds — is more difficult to clean up than oil, according to officials.
The levels of chloride and ammonia detected at the rupture site were “acutely toxic” to fish, according to the state’s Department of Health. The spill contaminated groundwater near Blacktail Creek and cleanup is expected to take at least five years.
“I think five years would be very optimistic,” says Dave Glatt, chief of the Environmental Health Section. “Ten years, there still may be talk about this.”
Before regulators will allow Meadowlark Midsteam to resume operation on the produced waterlines, they are requiring the use of SCADA, Helms says.
“We want real-time pressure readings, meter readings and temperature readings,” Helms says.
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