Los Angeles County Supervisor Michael Antonovich has called for an independent study of the long-term impacts of the massive Aliso Canyon gas leak.

Previewing a motion he plans to make next week, Antonovich said the scale of the leak warrants further study.

“Considering the magnitude of this gas leak — the largest in history — and the resulting multitude of health complaints, it is vital for the well-being of the residents in these communities that we conduct a comprehensive health study to determine any potential long-term health threats,” Antonovich said.

But Alexandra Nagy, a senior organizer for Food & Water Watch, said the problems at Aliso Canyon are too numerous.

“It’s time to shut the facility down for good,” Nagy said.

“No fine can make SoCalGas’ aging Aliso Canyon Storage Facility safe. We just had a fourth leak since last October’s blowout, which shows that the facility is beyond simple repair and continues to pose a threat to the health of the families of Porter Ranch and to the environment. What’s more, this fine is barely a slap on the wrist for SoCalGas whose parent company made $10 billion in revenue last year.”

The natural gas leak that began last Oct. 23 at the Southern California Gas Co. storage facility forced thousands of residents to relocate temporarily. The leak was shut down 16 weeks later, on Feb. 11.

By that time, the leak had spewed more than 100,000 tons of methane into the air, making it the largest methane leak in U.S. history, according to a study released in February by UC Davis, the National Oceanic and Atmospheric Administration and others.

At the peak of the leak, the amount of methane pouring into the air from the damaged pipe was double the rate of methane emissions from the entire Los Angeles basin, according to the study.

Even after the leak was capped, many residents continued to report health problems such as migraines and respiratory irritation.

In January, the South Coast Air Quality Management District’s (SCAQMD) hearing board ordered Southern California Gas Co. to fund a health study. In July, SCAQMD sued for enforcement.

Chris Gilbride, spokesman for SoCalGas, said the utility has agreed to spend up to $400,000 to fund the health study.

“To date, AQMD has not provided SoCalGas with a proposed health study plan to be funded by SoCalGas,” he said. “What AQMD has discussed is an NAS-led scoping effort that would delay the start of this health study, which we understand the community is also eager to see completed. SoCalGas continues to urge the AQMD to provide a proposal for and to quickly begin a health study.”

Antonovich said the California Air Resources Board, the state’s Department of Public Health, Cal/EPA’s Office of Environmental Health Hazard Assessment and the Environmental Protection Agency all support a health study.

“The Gas Company should live up to its responsibility and commitments by fully funding this vital health long-term health study,” Antonovich said.

SoCalGas has consistently maintained that there is no health hazard.

“Since the well has been sealed, thousands of samples have been taken by regulatory agencies, including the Department of Public Health (CDPH), of the indoor and outdoor air, and of soil and dust in selected homes in the Porter Ranch community,” the utility said in a statement issued in July regarding clean-up. “Public Health’s own testing results have detected no substance above state or federal levels of concern.”

A DPH report found that surface dust in many homes contained “low levels of metal contaminants” consistent with those found in well-drilling fluid and concluded that “these metals do not pose long-term health risks but can cause respiratory and skin irritation and could be contributing to symptoms reported by residents.”

For Nagy, it was more evidence that the Aliso Canyon facility should be closed.

“Residents continue to experience symptoms like dizziness, headaches and nosebleeds,” Nagy said. “Adding insult to injury, their continued sickness may be pointless— a recent study prepared for Food & Water Watch shows that Aliso Canyon is not needed to keep the lights on and the stoves lit in the LA Basin through the winter peak season.”

Pressed by county officials, SoCalGas contractors cleaned approximately 1,700 homes in the area and most of the displaced residents returned in June.