NOXIOUS PLUMES: The Aliso Canyon underground storage facility in the Santa Susana Mountains, Los Angeles, has been leaking tonnes of natural gas into the atmosphere
NOXIOUS PLUMES: The Aliso Canyon underground storage facility in the Santa Susana Mountains, Los Angeles, has been leaking tonnes of natural gas into the atmosphere

Dangerous methane leak is ‘biggest in US history’

On Thursday, thousands of Los Angeles residents were left feeling sick and forced out of their homes after a natural gas leak from a gas storage facility in Southern California.

Scientists reported it was the largest known release of the climate-changing greenhouse gas, methane, in US history.

If you were to measure the equivalent impact on the climate in car emissions, it would be the combination of the annual fumes released from half a million cars.

The leak was first detected on 23rd October, and it was found that it was coming from one of the 115 wells connected to a massive underground natural gas storage facility – the fifth largest in the US.

Southern California Gas Company (SoCalGas), who own the facility, made seven unsuccessful attempts to shut down the billowing plumes of methane and ethane.

According to a study published in the journal ‘Science’, the 16-week blowout from the well has spewed around 107,000 tonnes of the powerful gas into the atmosphere.

The study was released the same day displaced residents staying in short-term housing were due to return home, but a judge issued an order requiring the gas company to provide housing for three more weeks.

The researchers say that the blowout will have a significant impact on California’s ability to meet its greenhouse gas emissions targets this year. Methane is a short-lived atmospheric chemical but is highly potent as a warming gas, with an effect 25 times higher than CO2 over a 100-year time period.

Lead author Dr Stephen Conley, from the University of California, Davis, told the BBC: “In terms of the methane release, Aliso Canyon is by far largest. It had the largest climate impact; it beats the BP oil spill.”

The leak has been blamed for nosebleeds, headaches, nausea, rashes and respiratory problems.

Some residents who returned home already have continued to complain of symptoms.

But the company, which said it was paying about $2 million a day in housing costs, argued that public health officials found there was no reason residents couldn’t safely return.

“Unfortunately, today’s ruling disregarded these findings,” the company said in a statement.