Infrared footage of the natural gas plume erupting from Aliso Canyon (Photo Credit: EDF

The massive methane gas leak that has been plaguing some Southern California residents since October 2015 has finally been sealed. The announcement that was accompanied by the release of a time-lapse video showing infrared footage of the gas leakage coming to a complete halt was made on February 11, by Dennis Arriola, CEO of the Southern California Gas Company (SoCal Gas).

The leak, which is being billed as one of the worst environmental disasters in US history occurred just outside Los Angeles in Aliso Canyon, the nation's second-largest natural gas storage facility. Though it began on October 23, it took SoCal Gas engineers a few weeks to identify the damaged well which was located 8,748-feet below the ground, deep under a layer of nonporous rock.

Relief well drilled by SoCalGas to plug the leaky well at Aliso Canyon. (Photo credit: SoCalGas)

Since then, the utility's engineers have been trying their best to seal the leak. After the initial quick fix solution failed, they decided that the only effective way to stop the gas outflow was by intercepting the damaged pipe with a newly drilled well and then plugging it with cement. This was no easy task given that the engineers had to drill into the 7-inch damaged pipe that lay at an angle, without impacting nearby pipes. Fortunately, they were able to complete the task without any further disaster.

The news that the leak had been sealed was met with much relief by the residents of the Porter Ranch Community, who have been forced to evacuate their homes and move to temporary housing since early November. Tests performed by the SoCal Gas and other independent environmental organizations indicate that it is safe for the 6,600 dislocated families to return home.

However, the nightmare is far from over for the utility company. SoCal Gas that has already spent about $300 million USD to fix the leaking well and relocate residents, is now required to conduct a full inspection of the other 114 wells at Aliso Canyon before additional gas can be pumped in. The company also faces several lawsuits from the L.A. County District Office as well as affected residents. It will also be required to pay several environmental fines.

Methane pollution surrounding Porter Ranch, LA, ( Photo credit: Energy Efficiency Team)

Unfortunately, even the stiffest of fines will not be able to curb the environmental impact of the leaked greenhouse gas. A February 25 study published by researchers from the University of California, Irvine, in the online Journal Science states that at its peak, the leak effectively doubled the methane emission rate of the entire Los Angeles Basin! The scientists estimate that all in all, about 97,100 metric tons of methane or the equivalent of 4.5 million car emissions a day, was released in the 112 days it took to fix the leak.