On Wednesday evening, California Governor Jerry Brown declared a state of emergency in Los Angeles County in connection with a massive natural gas leak that’s ongoing at a Southern California Gas Company storage facility. The leak, which began on October 23, has been spewing methane into the air at a rate of tens of thousands of kilograms (PDF) per hour.

Governor Brown’s declaration of a state of emergency requires that SoCal Gas and other gas storage facility operators throughout California start conducting daily inspections of well heads and implement infrared imaging technology to detect leaks. Facility operators will have to monitor the wells for mechanical integrity, gas pressure, and safety on an ongoing basis.

The emergency declaration doesn’t earmark any state funds to help fund a cleanup, but it orders the California Public Utilities Commission to "ensure that Southern California Gas Company covers costs related to the natural gas leak and its response, while protecting ratepayers.”

The leaking storage facility is located in the Aliso Canyon area, just north of Los Angeles, close to the community of Porter Ranch. SoCal Gas has insisted that the leaking methane is not damaging to human health, but it has relocated thousands of Porter Ranch residents due to the fact that the odorless, colorless, very flammable methane is treated with chemicals that can cause headaches, nausea, and nosebleeds.

The most pressing concern, however, is that methane is a very potent greenhouse gas whose "impacts can be tens, hundreds, or even thousands of times greater than that of carbon dioxide,” according to the California Air Resources Board, although methane’s impact on the atmosphere is shorter-lived than CO 2 ’s.

SoCal Gas began digging a relief well after other methods of trying to stop the leak failed. The company has estimated that it could take up to four months to plug the leaking well. As part of his declaration yesterday evening, Governor Brown said that SoCal Gas must withdraw as much of the leaking natural gas from the storage facility as it can, as fast as it can, and it must try to capture leaking gas while relief wells are being drilled. Earlier this week, SoCal Gas installed mesh screens over the leak site to prevent an oily mist of gas and brine water that has started to emanate from the leak into the air. According to the Los Angeles Times, Porter Ranch residents "are finding droplets of dark brown residue on their homes, vehicles, fish ponds and gardens. Some are collecting samples on dinner plates, then forwarding photographs of the material to their lawyers.”

Reused oil wells How did SoCal Gas get those wells so deep? The natural gas storage wells at Aliso Canyon are actually cavities in the Earth that used to hold oil. The 115 wells How did SoCal Gas get those wells so deep? The natural gas storage wells at Aliso Canyon are actually cavities in the Earth that used to hold oil. The 115 wells were sucked dry of their oil and then the abandoned oil field was repurposed in the 1970s to hold 86 billion cubic feet of natural gas, according to the Los Angeles Daily News. Even today, Aliso Canyon is one of the biggest natural gas storage facilities in the country.

The California Office of Emergency Services also set up a website to act as a portal for daily updates on the leak. As of Thursday, the site reported that the main relief well (there’s a second relief well being drilled in case the first doesn’t work), has been drilled to a depth of 5,393 feet. The sandstone storage area for the natural gas is located 8,500 to 8,700 feet beneath the ground.

Other orders in Governor Brown’s emergency declaration require SoCal Gas to come up with another plan of action if its relief well and its backup relief well both fail. In addition, the gas company is prohibited from injecting more gas into non-leaking wells at the Aliso Canyon Storage Facility "until a comprehensive review of the safety of the storage wells and the air quality of the surrounding community utilizing independent experts is completed.”

Groups like the Environmental Defense Fund (EDF), which released a spooky aerial infrared video of the methane plume last month, have said that the Aliso Canyon leak underscores the fact that there are gas leaks on a smaller scale every day due to old infrastructure that utilities fail to replace in a timely fashion. While applauding Brown's action, EDF noted, "Leaks from the oil and gas industry occur every day, and Aliso Canyon is an extreme example of what can happen when companies don’t properly monitor and maintain aging oil and gas infrastructure."

Listing image by Governor's Office of Emergency Services