Pigs may not be able to fly, but they sure can clean.
British Petroleum is set to begin "pigging out" an abandoned undersea oil pipeline early next week. The pig is a mixture of nontoxic foam and gel that is sent through the pipe, causing anything remaining inside to be forced out, according to BP spokesperson Paul Laird.
"It's basically a very large slug of gel that's inserted into the line. It will squeeze anything remaining inside to the other end," Laird said.
He explained that, first, a large piece of foam will be inserted into the pipe, followed by about 900 feet of a special, nontoxic gel, followed by yet another piece of foam. Laird said the foam has about the same consistency as a pair of foam ear plugs, though much larger. The initial process is expected to take about 24 hours.
The work is being done because the pipe was determined to be the source of a mysterious sheen of oil discovered in Cook Inlet last summer. It was unknown for several weeks where the oil was coming from, due to the obscurity of the line.
Laird said once the source of the the sheen was discovered, BP began using a vacuum pump to suck out most of the oil remaining in the pipe. However, a small amount of oil is suspected to still be clinging to the sides of the pipe.
"There appears to be a small amount of oil left in the pipe. We believe the amount is very limited. Our estimate is 2 barrels, max," Laird said.
He said the pipe in question hasn't been in operation since the early 1970s. It was once used by Amoco to connect the Anna platform with Amoco's onshore processing facilities on the west side of Cook Inlet. Laird said in 1974, the pipeline apparently broke, was flushed out with sea water, capped and then abandoned by Amoco. When BP purchased Amoco, it also took over responsibility for the abandoned line.
Laird said the section of pipe that will be pigged runs from where the line was capped to shore.
BP is keeping area spill monitoring and environmental agencies appraised of its operation. Laird said BP has notified Cook Inlet Spill Response and Prevention Incorporated of its pigging plan. He said it is possible the pig could force some residual oil into the inlet, therefore CISPRI needed to be involved.
CISPRI General Manager Doug Lentsch said they'll closely watch the surface of the inlet for any signs of new contamination.
"If there's any oil released, we'll be out there to clean it up," he said.
Lentsch said CISPRI will have at least two boats on the inlet during the process. He said although BP is responsible for cleaning its own pipes, he's pleased the oil giant has worked to keep CISPRI apprised of the situation.
"It's their operation," he said. "They have been very good about keeping us informed."
Lentsch added that CISPRI's role in the pigging process will be to simply monitor what's going on.
"It's what we do," he said.
The Alaska Department of Environmental Conservation also will monitor the process. DEC spokesperson Leslie Pearson said her agency has been working with BP throughout the winter to coordinate the operation.
"We had meetings all winter long. We've been in close coordination with them. Also, we did coordinate with Fish and Game and the Department of Natural Resources," Pearson said.
She said the process is somewhat unusual in that the gel pigging process is new to the area. Pearson said she believes it's the first time the foam-gel-foam process has been used in the inlet to flush out a pipeline.
"I wouldn't say it's routine," she said.
Pearson said the DEC will be out on the inlet to make sure everything goes smoothly.
"As soon as we figure out when its going to begin, we'll be involved in aerial overflights," to look for any oil releases, she said. She said DEC would have a boat patrolling the inlet, as well.
The pig is scheduled to begin its trip through the pipe either this weekend or early next week, according to BP.
"The soonest we'll start is Saturday. Sunday or Monday is more likely," Laird said.
Peninsula Clarion ©2015. All Rights Reserved.