Leak detection drew a significant amount of discussion at a pipeline conversion hearing for Hess, which is seeking to convert 19 miles of 10-inch and 16-inch crude oil gathering lines in McKenzie County into a transmission line for its Keene Oil facility.
Since it is a conversion, ground disturbance and environmental impacts are not generally the big issue, Commissioner Julie Fedorchak said. The focus shifts to reclamation, emergency response, and to waivers for landowners within 500 feet of the line.
That said, however, commissioners also must consider the project as if it is not already in the ground. They need to know the parameters of initial construction and use as well, Commissioner Brian Kroshus said.
“I cannot just fast forward to three booster pumps,” he said. “I think it’s really important for the company to recognize, at least for myself, that I’m viewing this as if it’s not even in the ground.”
Conversions are in some ways more … delicate, in the words of Fedorchak.
The new line will have a lot more pressure, she pointed out in later testimony, and more volume.
“Tell me about the monitoring system,” she said. “How does it work? How sensitive is it?”
Dale Weathersby said the company would basically take the output from its wells using a meter placed there, and then at some stage along the line, would balance what is coming in with what is passing through downstream points.
“How many on ramps for this?” Fedorchak asked. “How often are those volume measurements taken?”
Weathersby indicated it could be as long as 24 hours.
“So you could have a leak for 24 hours and not know about it?” Fedorchak asked.
“Yes,” Weathersby said. “The reason being, that gathering systems typically have slack in the line.”
Fedorchak said she wonders if that will be adequate for a line that could have up to 100,000 barrels per day in it.
“It probably won’t be that much,” Weathersby said. “It would be nice if it’s stacked like that, but it probably won’t be.”
“But it could be?”
“Yes,” Weathersby acknowledged.
Weathersby did not know who specifically is monitoring the line, but said there are many employees in that area.
“So they are close?” Fedorchak asked.
Fedorchak also asked about electronic monitoring in unusually sensitive areas versus not so sensitive ones.
In areas of unusual sensitivity, companies typically do more monitoring, Weathersby acknowledged, but the area the line is in is not considered unusually sensitive.
“Well, I’m thinking of the spill in the Tioga farmer’s field,” Fedorchak said. “That’s probably not an unusually sensitive area either?”
“But it would have been valuable to detect that leak a lot sooner, I think we’d all agree,” Fedorchak said. “The cost to the company has been exorbitant to clean all that up. I guess, the bottom line is, I need to know more about the company’s leak detection before we approve increasing the amount of pressure and the amount of oil going through it, whether it’s an unusually sensitive area or not.”
Weathersby said the decision about how intense to go with electronic monitoring on any given line is generally a business decision.
“We still have that option, if the business believes that is the way we should go,” he said.
“Well, maybe the company should provide that information to us and update it,” Fedorchak said.
Kroshus wanted to know about response times in the event of a spill.
“How quickly can they move to shut it down once they know about a problem?” he asked.
Weathersby said typically, it would be about an hour. But in some cases it has been as little as a half hour, depending on the location and circumstances.
Kroshus also wanted to know if additional meters along the line might help reduce response times by isolating the leak better.
Weathersby agreed it would help isolate the problem, but that it wouldn’t necessarily reduce response times.
Kroshus also wanted to know why the line couldn’t have leak detection like that on the Keystone line, where a drop in pressure was immediately spotted by electronic monitoring and led to a very rapid shutdown and emergency response.
The big difference, Weathersby explained, is that Keystone is a transmission line. That means it’s in a steady state at all times, so a pressure drop is immediately indicative of a problem.
But in a gathering line, which is what Hess’s line would also be, the flow is not steady. There is a lot of slack time, and so pressure drops do not necessarily mean anything is wrong.
Leak detection on those types of systems is challenging, and even a very expensive system can fail because of the complexities involved.
The state, Weathersby pointed out, is presently working on a study to determine what types of leak detection systems would be most effective and economically feasible, and Hess is a participant in those studies.
“It’s not a cut and dried answer,” Weathersby said. “If it were, everyone would be doing it already.”
Jim Talbert, McKenzie County Planning and Zoning Director was among members of the public testifying at the hearing.
He praised commissioners for looking at the project as if it is not yet in the ground, and said he believes that is the right emphasis to take.
He urged commissioners to consider a thorough inspection prior to lines being converted, to ensure that any converted line is treated as stringently as a brand new transmission line would be. He also asked the commission to consider developing a noise level where deadening modifications would be required on oilfield equipment.