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Refugio oil spill

2015 pipeline leak on the coast of California

  • 20 min read
  • 4 chapters

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Through Petroleum, Oil spill and Natural gas

Hundreds of animals along the coast were coated with thick crude oil and many died. State parks and beaches located along the Gaviota Coast were temporarily closed. While much smaller than the oil rig blowout that resulted in the 1969 Santa Barbara oil spill, this incident may have greater long term effects due to its potential impact on four state marine protected areas. Due to the unique characteristics of the area, it is one of the most studied marine environments in the United States.

The oil spill, north of Refugio State Beach, originated in a 2 feet (61 cm) diameter underground pipeline designated Line 901 owned by Plains All American Pipeline. Crude oil produced by offshore platforms was transported from onshore receiving plants to another pipeline that transported the oil inland for processing. The 28-year-old pipeline was not equipped with an automatic shut-off valve and was eventually shut down by control operators in Midland, Texas when they were notified of the leak from parties who visually located the spill.

A subsidiary of ExxonMobil acquired the pipeline from Plains All American Pipeline in 2022 as three platforms owned by ExxonMobil used the pipeline to transport the oil after it arrived onshore. A new company, Sable Offshore Corp., was formed to own and operate the pipelines and the Santa Ynez Unit which includes the offshore oil platforms and an onshore processing facility.

Background

The area was one of the earliest locations in California developed for offshore oil and gas production. Crude oil and natural gas produced by offshore platforms is processed at onshore receiving plants before being transported to distant refineries. The source of the spill was Line 901, a 10.6-mile pipeline (17.1 km) owned by Plains All American Pipeline. The 24-inch buried line (610 mm) was constructed in 1987 along the Gaviota coast to service the crude oil produced by offshore drilling. The pipeline can transport 48,000 barrels (2,000,000 U.S. gal; 7,600 m3) a day and the contents are heated to as high as 120 °F (49 °C). Santa Barbara area pipelines are typically not heated but they are insulated to retain the oil's heat during transit. The viscous oil is also blended with natural gas liquids to allow it to flow more readily through the pipeline. Truck transportation of oil was phased out in Santa Barbara County in the 1970s because pipelines were considered a safer option.

Pipeline corrosion

Before the spill, an inspection of the 28-year-old Line 901 pipeline found extensive corrosion problems resulting in thinning pipeline walls. The pipeline did not have an automatic shut-off valve that would have been required on an intrastate pipeline as Line 901 is categorized as an interstate pipeline. Officials from Plains All American Pipeline claimed that installing a new valve would present other potential dangers. The line underwent a comprehensive internal inspection in July 2012 and since then the area where the pipe broke had been repaired at least three times. Line 903 is a much longer pipeline that transports the oil from Line 901 inland to gathering facilities and refineries. Line 903 was also found to be corroded though not as seriously.

Offshore oil production

Of the seven offshore platforms that used the line, ExxonMobil owned three: Hondo, Harmony and Heritage. After delivering their oil to onshore tanks at its Santa Ynez Unit in Las Flores Canyon, they depended on Line 901 to transport the oil from Las Flores to a pump station in a coastal canyon near Gaviota. The crude oil, known as Las Flores Canyon OCS (Outer Continental Shelf), then flowed into Line 903 as it was transported inland 128 miles (206 km) to gathering facilities in Kern County and on to refineries throughout Southern California. Venoco's Platform Holly located in the South Ellwood Offshore Oil Field also depended on Lines 901 and 903. The Holly platform is about two miles (3 km) offshore from the Coal Oil Point where about 4,000 U.S. gal (95 bbl; 15 m3) a day comes from natural seeps. Line 903 was also used to move the production from platforms Hidalgo, Harvest and Hermosa of Point Arguello Unit owned by Freeport-McMoRan to the ConocoPhillips refinery in Santa Maria.

Gaviota Coast

The narrow coastal terrace where the spill took place is primarily used for recreation and cattle grazing. Local land use agencies have kept oil processing facilities to a minimum along the lightly populated coastline where much of the land is held in agricultural preserves under the Williamson Act and used for avocado and lemon tree orchards. The parks and agricultural areas on this narrow coastal terrace are situated between a rugged coastline and the Santa Ynez Mountains of the Los Padres National Forest. The nearest city is Goleta, about eleven miles (18 km) down the coast. US 101 and the main coastal railroad line both parallel the coastline and the Hondo and Harmony oil rigs can be easily seen offshore in the Santa Barbara Channel from the highway or railroad.

The Gaviota coast with its Mediterranean climate is considered unique for the biodiversity of ocean life. The unusual species found here are the result of the cold water from the north meeting the warm water from the south. The annual migration of about 19,000 Gray whales through the Santa Barbara Channel was in progress at the time of the spill. They may come as close as 100-foot (30 m) from the shoreline.

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