The largest, Prudhoe Bay, started production four years earlier, and has already had serious corrosion problems on its pipelines.
During its first 25 years in operation, the Kuparuk pipeline extension has transported over 73m brl of oil into the gathering facilities at Prudhoe Bay in preparation for sending it down the trans-Alaska pipeline to tankers in Valdez. Currently, Conoco can’t pig the above-ground pipeline because of its odd design: about half of the line is 12in diameter, while the rest is 18in diameter. As a result, the field operator can only check the line externally, using ultrasound equipment; the upgrades will enlarge the narrower section, making the entire pipeline 18in diameter.
Conoco is to build pig-launching and -receiving terminals in the basins used for collecting snow during winter cleanups and meltwater during spring breakup, and the company expects to finish the project within two years. Conoco voluntarily evaluated its pipelines at Kuparuk under a programme overseen by the US Department of Transportation which requires the company now to conduct further inspections, and the use of smart pigs will allow the company to inspect the pipeline to DOT standards by the agency’s deadline in May 2011. Conoco is the main lease holder at Kuparuk. Other oil companies with interest there include BP, Chevron, and Exxon Mobil.