The Aliso Canyon gas leak was the largest in the history of the US. 100,000 tonnes of methane had entered the air before it was stopped. It is worse than the oil spill in the Gulf of Mexico back in 2010.
In October, one of the 115 wells leaked and despite seven attempts to stop the methane escaping, the Southern Gas company were unable to stop it. As a result, 11,000 residents were evacuated, and a state of emergency was declared. It was not until February 18th that the leak was sealed for good.
READ ALSO: Urban Farmers Earn $75,000 on 15,000 Square Feet Space
(A) Plume C2H6-to-CH4 enhancement ratios from airborne measurements (black circles) and ground-based WAS measurements (red square). (B) CH4 (black) and C2H6 (blue) leak rates from airborne measurements. Redline is a fit to the airborne CH4 data assuming an average leak rate from blowout to day 43, an exponential decrease between days 43 and 80, and an average leak rate after that to day 112 when control was restored. (C) The Total amount of CH4 released calculated from the fit in 2B. Error bars indicate ±1 standard error of the mean.
As a result, benzene, xylenes, and toluene – all chemicals that can be dangerous – have been found in samples although there is some good news, as it is believed that lessons have to be learned. It was luck more than planning that allowed the spill to be found as work was being carried out elsewhere when the request was made for a flyover.
It is considered to have been a significant oversight, and there are fears for the ability to measure future emissions. Leaks such as this are likely to happen again unless serious plans are set in place to prevent them.
The research has been published in the Science magazine.