Tag Archives: Methane Leak

California methane leak was biggest ever in U.S., scientists say

LOS ANGELES (Reuters) – The months-long natural gas leak that forced thousands of Los Angeles residents from their homes ranks as the largest known accidental methane release in U.S. history, equal to the annual greenhouse gas emissions of nearly 600,000 cars, scientists reported on Thursday.

At its peak, 60 tons per hour of natural gas was spewing from a ruptured underground pipeline at the Aliso Canyon storage field, effectively doubling the methane emissions of the entire Los Angeles metropolitan area, the researchers said.

Their study, published in the journal Science, represents the first comprehensive effort to quantify a gas leak that sickened scores of people and prompted the temporary relocation of more than 6,600 households from the northern Los Angeles community of Porter Ranch at the edge of the gas field.

From the time it was first detected on Oct. 23 until it was plugged earlier this month, the damaged injection well discharged a total of 97,100 tons – or 5 billion cubic feet (142 million cubic meters) – of methane to the environment, according to the study.

The chief component of natural gas and a far more potent greenhouse agent than carbon dioxide, methane persists in the atmosphere for 10 years. The total release from Aliso Canyon is equivalent to the annual energy-sector methane emissions of a medium-sized European Union country, the study said.

“Our finding means that the Aliso Canyon leak was the largest accidental release of methane in the history of the U.S.,” Tom Ryerson, a scientist for the National Oceanic and Atmospheric Administration (NOAA), and co-lead of the study, said in a NOAA statement about the research.

The 2004 collapse of an underground gas storage facility in Texas actually expelled more natural gas, but it was mostly consumed in an explosion and fire, so that methane never reached the atmosphere, the study said.

“Aliso Canyon will have by far the largest climate impact” and will “substantially impact the state of California greenhouse gas emission targets for the year,” the study said.

In terms of its heat-trapping greenhouse potential, the volume of leaked methane was equivalent to putting 572,000 passenger cars on the road for a year, according to the scientists.

The Aliso Canyon facility, owned by Southern California Gas Co, a division of San Diego-based Sempra Energy, is the fourth largest gas storage field of its kind in the United States.

The volume of methane that escaped represents just 3 percent of its total storage capacity, “raising the possibility of substantial additional emissions” had the leak not been plugged or the field drained of remaining gas supplies, the study said.

Environmental groups have seized on the Aliso Canyon breach to call attention to hazards posed by the state’s aging fossil fuel infrastructure.

The leak also has triggered a wave of legal action. SoCal Gas has pleaded not guilty to criminal misdemeanor charges stemming from the release, which prosecutors said the utility failed to report in a timely manner. Local, state and regional authorities, as well as dozens of residents, have also sued the company.

The study was based on data collected from numerous airborne and ground-based measurements taken during the course of the blowout and analyzed by teams from NOAA, the California Energy Commission, two University of California campuses and the University of Colorado at Boulder.

(Reporting by Steve Gorman; Editing by David Gregorio and Alistair Bell)

Los Angeles-area methane leak declared permanently sealed

LOS ANGELES (Reuters) – An underground natural gas pipeline rupture that caused the largest methane leak ever in California has been permanently capped, paving the way for thousands of displaced Los Angeles residents to return home, state regulators said on Thursday.

The leak, which began in October, was confirmed by a series of independent laboratory tests to have been successfully sealed as of Wednesday night, officials said.

The leak originated from a broken injection-well pipe deep beneath the surface of the 3,600-acre Aliso Canyon natural gas storage field, owned by Southern California Gas Co.

State officials said the uncontrolled release of 80,000 tonnes of methane, the main component of natural gas and a far more potent greenhouse agent than carbon dioxide, ranked as the largest such discharge on record in California.

Environmental groups seized on the breach to call attention to hazards posed by the state’s aging fossil fuel energy infrastructure, and Governor Jerry Brown declared the gas leak a state emergency.

The stench of fumes spewing from the site sickened scores of people for weeks and prompted the temporary relocation of more than 6,600 households from the northern Los Angeles community of Porter Ranch, located at the edge of the gas field.

Jason Marshall, chief deputy director of the California Department of Conservation, said it was now safe for residents to return, and that the utility had agreed to continue paying their relocation expenses through next Thursday morning.

The announcement came a day after the utility, a division of San Diego-based Sempra Energy, pleaded not guilty to criminal misdemeanor charges stemming from the leak, which prosecutors said the company failed to report in a timely manner. Local, state and regional authorities, as well as dozens of residents, have also sued SoCal Gas.

In addition to possible fines and civil liability the company faces, the utility expects pipeline repair costs and housing relocation expenses will end up running about $300 million, said SoCal Gas Chief Executive Officer Dennis Arriola.

The actual leak was apparently staunched late last week. The utility said on Friday that infrared monitoring by state regulators showed that a newly drilled relief well had managed to finally intercept the pipeline breach and halt the gas flow.

A series of follow-up emissions and infrastructure tests has confirmed that the cement plug pumped into the crippled injection well pipe was holding, Marshall said.

(Reporting by Paula Lehman; Writing and additional reporting by Steve Gorman; Editing by Bill Rigby and Lisa Shumaker)

California utility ‘temporarily controls’ leaking gas flow

(Reuters) – Southern California Gas Co said on Thursday it has temporarily controlled the flow of natural gas spewing from a ruptured underground pipeline that forced the relocation of thousands of residents of a Los Angeles neighborhood.

The company, a unit of Sempra Energy, said in a statement that while this was a “positive development,” more work needed to be done before the leak would be permanently sealed. It said cement needs to be injected from a relief well into the leaking well, which is slated to occur in the coming days.

Following that, state regulators would have to verify that the leak has been sealed before it will be declared over, the company said. That process is expected to take several more days.

“We have temporarily controlled the natural gas flow from the leaking well and begun the process of sealing the well and permanently stopping the leak,” Jimmie Cho, SoCalGas senior vice president of gas operations and system integrity, said in a statement.

The leak stems from an underground pipeline rupture at the company’s 3,600-acre Aliso Canyon natural gas storage field. The leak, detected on Oct. 23, is believed to have been caused by a broken injection-well pipe several hundred feet beneath the surface of the field.

The largest such leak ever in California, at its height it accounted for a fourth of all methane emissions statewide.

Thousands of residents of the Porter Ranch community near the field were forced to relocate because of the leak. SoCalGas said it would wind down its relocation program for displaced residents once the California Division of Oil, Gas and Geothermal Resources confirms the leak has been sealed.

More than 20 lawsuits against SoCalGas have been filed by residents over the leak, along with civil claims by Los Angeles city and county, the state of California and air quality regulators. County prosecutors have also filed criminal charges.

A week ago, the first wrongful death claim over the methane leak was filed, saying the conditions hastened the demise of an elderly woman already suffering from lung cancer.

(Reporting by Curtis Skinner in San Francisco; Editing by Leslie Adler and Cynthia Osterman)

First wrongful death claim filed over California methane leak

LOS ANGELES (Reuters) – Methane fumes spewing from a ruptured underground pipeline near a Los Angeles neighborhood hastened the demise of an elderly woman already suffering from lung cancer, her family said in the first wrongful death claim stemming from the gas leak.

The lawsuit seeks unspecified monetary damages against Southern California Gas Co, a division of San Diego-based Sempra Energy, for the suffering and death of Zelda Rothman, 79, who died on Jan. 25, about three months after the leak was detected.

Rothman, who lived about 3 miles from the source of the escaping methane at the Aliso Canyon natural gas storage field, was leading an active life, despite her diagnosis of stage 4 lung cancer, her family’s lawyer, Scott Glovsky, said on Thursday.

“She was going on cruises, and going out to lunch with friends and driving,” Glovsky said.

Her fragile condition began to worsen in the weeks after the leak began as she suffered from increasingly labored breathing and extreme headaches, requiring round-the-clock oxygen support by December, according to the lawsuit.

Rothman, a decades-long resident of the Porter Ranch community where thousands of residents have been temporarily relocated at the utility’s expense, was moved into a hospital after her adult children visited in December, Glovsky said.

The complaint blames her rapid decline on exposure to methane, the principal component of the escaping natural gas, and other contaminants within the gas. Ranked as the largest such gas leak ever in California, it accounted for a fourth of all methane emissions statewide at its peak.

“We’re not claiming the gas company caused (Rothman’s) cancer,” Glovsky said. “We’re claiming they essentially poisoned her and hastened her death and destroyed the quality of her life in the time she had left.”

The lawsuit, filed on Tuesday, asserts the utility could have halted the leak soon after it was detected if the ruptured well were equipped with a “sub-surface safety valve,” which the complaint said the company removed in 1979.

“We are sorry to hear about the family’s loss,” company spokeswoman Kristine Lloyd said of the wrongful death claim. “We are reviewing the lawsuit and will allow the judicial process to take its course.”

More than 20 lawsuits against SoCal Gas have been filed by residents over the leak, along with civil claims by Los Angeles city and county, the state of California and air quality regulators. County prosecutors filed criminal charges on Tuesday.

(Reporting by Steve Gorman; Editing by Peter Cooney)

Prosecutors file criminal charges in methane leak near Los Angeles

LOS ANGELES (Reuters) – Los Angeles prosecutors filed criminal charges against the Southern California Gas company on Tuesday over a huge methane leak near the city that has forced thousands of residents from their homes since October.

The four misdemeanor charges accuse SoCalGas, a division of San Diego-based Sempra Energy, of failing to report the release of hazardous materials following the underground pipeline rupture and discharging air contaminants.

“While we recognize that neither the criminal charges nor the civil lawsuits will offer the residents of Los Angeles County a complete solution, it is important that Southern California Gas Co. be held responsible for its criminal actions,” District Attorney Jackie Lacey said in a written statement.

Lacey’s move came on the same day that California Attorney General Kamala Harris sued Southern California Gas Co, accusing the utility of violating state health and safety laws by failing to promptly control the escaping gas and report the leak to authorities.

The lawsuit also cites environmental damage caused by the uncontrolled release of 80,000 metric tons of methane, the prime component of natural gas and a far more potent greenhouse gas than carbon dioxide.

The leak stems from an underground pipeline rupture at the company’s 3,600-acre Aliso Canyon natural gas storage field. The largest such leak ever in California, at its height it accounted for a fourth of all methane emissions statewide.

The lawsuit amends a civil complaint brought in December by the Los Angeles city attorney and later joined by Los Angeles County. It seeks civil penalties and court orders requiring the utility to immediately take all steps necessary to mitigate the leak, repair the damage and prevent future discharges.

Several attempts to halt the methane release have failed, but the company said it hopes to plug the leak by the end of the month through a relief well.

The company said in a statement it would “respond to the lawsuit through the judicial process.”

Last week, the South Coast Air Quality Management District filed a separate lawsuit against SoCal Gas seeking civil penalties of up to $250,000 a day for each of six pollution-related health and safety code violations.

The methane fumes have sickened scores of people and prompted the relocation of more than 6,600 households from the Porter Ranch community at the edge of the crippled underground gas storage field.

More than 20 private lawsuits have been filed on behalf of some of those residents.

(Reporting Steve Gorman and Dan Whitcomb in Los Angeles, Dan Levine in San Francisco and Brendan Pierson in New York; Editing by David Gregorio, Tom Brown and Bernard Orr)