LOS ANGELES (Reuters) - California Governor Jerry Brown on Wednesday (Jan 6) declared a Los Angeles-area natural gas leak that has been sickening area residents for more than two months an emergency, calling for alternatives to stop the underground leak if existing efforts fail.
Southern California Gas Co., which operates the well that is the site of the underground methane leak, is trying to stop it by drilling a relief well to reach a damaged pipeline, then injecting fluids and heavy mud into it.
The governor's office said in a statement the utility will need to identify how it will stop the leak if a relief well fails to seal it - or if the existing leak worsens.
The leak was discovered on Oct 23 at a well used for natural gas storage in Aliso Canyon just outside Los Angeles' Porter Ranch neighborhood in the San Fernando valley, which is home to more than 30,000 people. Thousands of residents were forced to move over the holidays, with the company underwriting their temporary housing.
Officials from Southern California Gas, a division of Sempra Energy, have said they expect to stop the leak in late February to late March.
The leak, which state officials have said accounted at its peak for a fourth of California's 20 million tonnes a year in greenhouse gas emissions from methane, is believed to have been caused by a broken injection-well pipe several hundred feet beneath the surface of the 1,457ha field.
People in the area have complained of such ailments as headaches, nausea and respiratory irritation from mercaptans, the odorants added to natural gas, according to Los Angeles County health officials. They have said past studies found no long-term health effects from mercaptans.
The governor's office said it had taken steps to coordinate the local, state and federal response to the leak, which at last count was releasing more than 30,300 kilograms of methane per hour, and stop it as soon as possible.
The emergency declaration by Mr Brown, a Democrat, follows calls by local officials in Los Angeles for increased state regulation of gas storage facilities.
The emergency declaration makes clear Southern California Gas is responsible for covering costs from the leak and allows the governor's administration, if necessary, to quickly waive laws in the future to deal with the crisis, the governor's spokesman Evan Westrup, said.
Residents of Porter Ranch have said they want the gas field shut down.
For his part, the governor called for regulators to assess the long-term viability of natural gas storage facilities in California.
"As we have since this incident began, SoCalGas stands willing and ready to cooperate with the governor's office, all state and local officials and regulatory agencies," Mr Dennis Arriola, president and chief executive of the company, said in a statement.
The leaking storage field in Aliso Canyon is the second-largest such facility in the western United States by capacity.