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A hole in a Phillips Alaska's pipeline used for transporting drilling by-products at the Kuparuk oil field on Alaska's North Slope has resulted in the biggest spill of industrial material onto the tundra in recent years, the Alaska Department of Environmental Conservation (DEC) says. The spill was apparently caused by corrosion in a 10-inch pipe, said Ed Meggert, head of oil spill response with the state Department of Environmental Conservation in Fairbanks. (reference 73)
Corrosion from water and erosion from abrasive material such as sand is a growing problem on the North Slope. As Kuparuk and Prudhoe Bay age, the companies are grappling with internal pipe corrosion from water running through lines and external corrosion from water seeping between thick insulation and the hot transportation pipes. High temperatures and water make a perfect climate for corrosion.
The leak, discovered on Sunday night, caused a spill of 92,400 gallons of so-called "produced water," a mixture of salty water and oil, DEC said. For more than a decade, the oil companies have injected saltwater deep into oil fields to boost reservoir pressure and enhance oil flow. As a result, large amounts of water come out of the underground reservoir along with oil and gas. The mixture runs to the processing facility where the gas and most crude oil are stripped off. Then, operators send the water, along with some crude, back to the production pad and re-inject it to keep reservoir pressure high. The leak occurred in a line that returns the water and trace oil to Kuparuk production pad 1B. The leak happened at a road culvert close to where the pipeline leaves the processing facility's gravel pad, Dawn Patience, Phillips Alaska's spokeswoman, said.
Meggert said that although the oil content in the water was low, about 1 percent, the huge spill size means that independent of the saltwater, nearly 1,000 gallons of crude hit the tundra. That crude spill would be one of the 10 largest spills on the North Slope in the past five years, according to state statistics. The high temperature as it left the pipe may mean the mixture penetrated into the ground.
Meggert said the saltwater may be more damaging to the tundra than oil. Saltwater, if it seeps into the earth, kills the tundra plants and has lingering effects, he said. "It's just as toxic as diesel," he said. "The plants that normally grow die. The crude will only coat but the saltwater penetrates."
Meggert said the processed water, when it came out of the pipe, was about 100 degrees Fahrenheit. That heat melted a great deal of snow, a fortunate thing because it diluted the salt content, he said. "We're hoping it didn't penetrate too far," he said. Meggert said the warm salt water likely defrosted the top layer of the frozen tundra, meaning the area is now saturated with plant killing salt. The temperature was 9 degrees Fahrenheit at the time of the spill.
The general strategy for cleaning saltwater from the tundra is to flush the area with fresh water, Meggert said. In the coming days the spill area will likely be diked with sandbags and flooded with freshwater and, possibly, a chemical agent to flush the salt and crude from the tundra. The cleanup is expected to last for a few weeks, he said. As of Tuesday morning, 92,700 gallons of material had been scooped up, Patience said. Much of that may have been snow and ice melted by the hot crude and water mixture.
Some of the produced water reached a tundra pond and created an oily sheen that is floating on the top, DEC said. Phillips is working with DEC, the North Slope Borough and Alaska Clean Seas, an industry cleanup cooperative, to come up with a long-term plan for stabilizing the area, Patience said.
The leak occurred at Phillips Alaska's Kuparuk oil field, which is North America's second largest. Although there have been bigger spills on the North Slope, "This is probably the biggest spill to tundra that we've had," said Ed Meggert, the Fairbanks-based manager of spill response for DEC.
It was the fourth major spill on the North Slope in the 2001 winter and the second believed to be caused by erosion or corrosion. Corrosion from water and erosion from abrasive material such as sand is a growing problem on the North Slope. As Kuparuk and Prudhoe Bay age, the companies are grappling with internal pipe corrosion from water running through lines and external corrosion from water seeping between pipe insulation and hot steel pipe walls, where it eats at the metal.
The Kuparuk field, the nation's second largest, produces about 230,000 barrels of oil a day. BP is the other major leaseholder at the unit. The three other serious spills on the North Slope in recent months were all at BP-operated facilities.
The accident timing is bad for Alaska's big oil companies and state leaders who are trying to put a positive spin on the oil industry's environmental record in an effort to open the Arctic National Wildlife Refuge to drilling. Phillips is one of three oil giants in Alaska that are lobbying to have part of the Arctic National Wildlife Refuge opened to oil and gas drilling. Along with ExxonMobil and BP, Phillips has argued that the North Slope of the refuge - located about 90 miles east of existing oil fields - could be exploited with little risk to the environment. But the new spill illustrates that spilled oil is not the only environmental risk from oil drilling. The refuge is about 90 miles east of existing oil fields.
