One of the biggest oil spills in the US in almost a decade, more than 14,000 barrels of crude oil spilled into a Kansas creek, prompting TC Energy of Canada to temporarily shut down its Keystone pipeline.

The leak, which happened in Kansas about 20 miles south of a crucial intersection in Steele City, Nebraska, still has unidentified causes. Since the pipeline's initial opening in 2010, there have been three spills totaling several thousand barrels of crude oil.

A vital route for delivering heavy Canadian crude from Alberta to refineries in the Midwest and Gulf Coast of the United States is the 622,000-barrel-per-day Keystone line.

The US Environmental Protection Agency said that although Mill Creek's surface water was impacted, neither the public nor drinking water wells were affected.

Kellan Ashford, the spokesperson for EPA Region 7, said that by Thursday night, it was still unknown what caused the leak.

Canada's TC Energy

According to Ashford, TC had sent out about 100 responders to the spill, compared to the EPA's two coordinators. Additionally present were Kansas's Department of Health and Safety and Washington County Emergency Management.

After sirens went off and system pressure dropped, Keystone shut the line down at around 8 PM CT on Wednesday (0200 GMT Thursday), according to a release from TC. It stated that the spill was contained with booms.

According to a statement released by the US Pipeline and Hazardous Materials Safety Administration (PHMSA) late on Thursday, the pipeline must stay closed until the regulator approves a restart. In addition, when Keystone is restarted, it will need to run at a lower pressure in the line's affected section.

According to TC Energy, the business has run the pipelines, storage facilities, and power plants that keep Canada, the US, and Mexico's populations alive for more than 70 years. Their facilities run smoothly, dependably, and safely.

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Largest Crude Oil Leak

This would be the biggest crude oil leak since a Tesoro pipeline in North Dakota spilled over 20,000 barrels of oil in October 2013, according to PHMSA data.

PHMSA is also investigating the leak, which occurred close to the town of Washington, Kansas, which has 1,000 residents.

Seven spills have occurred at the Keystone pipeline since it began operating in June 2010, according to PHMSA data. According to data from PHMSA, the largest spill occurred in South Dakota in December 2017 and involved more than 6,600 barrels.

About two months after TC announced it would temporarily increase the system's capacity to test some operations, there was a spill. Keystone can be operated by TC with a special permit at a higher level of stress than other US crude lines.

Previous Oil Spill. The Macondo Prospect in the Gulf of Mexico was being worked on when the Deepwater Horizon oil drilling rig exploded and sank on April 20, 2010. This resulted in the largest oil spill ever in marine oil drilling operations. EPA reports that 11 crew members died in the incident. Before it was finally sealed off on July 15, 2010, 4 million barrels of oil poured out from the leaking Macondo for 87 days.

Indefinite Shutdown

Regarding the outage, TC issued a force majeure declaration, which is used to describe unforeseen external events that make it impossible for a party to a contract to fulfill its obligations.

Two Keystone shippers asserted that TC had not yet let them know how long the pipeline closure might last.

The closure of Keystone will hinder deliveries of Canadian crude to the Gulf, where it is refined or exported, as well as to the storage hub in Cushing, Oklahoma.

According to Reuters, the shutdown is anticipated to widen the Western Canada Select (WCS) heavy oil discount from Alberta to US crude, which was already substantial due to the weak demand for heavy, sour Canadian oil.

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