It’s been two years since the leak at the Aliso Canyon gas storage facility was discovered, causing extensive pollution around Porter Ranch.

As KPCC’s Sharon McNary reported in 2016, about 5.4 billion cubic feet of methane sprung from the leak, along with trace amounts of other chemicals. The failed well was 63-years-old. Some of the other wells are even older and were in need of maintenance. It was months before the leak was plugged by the Southern California Gas Company, which is in charge of facility operations.

State utility and gas regulators were also warned in 2009 about seismic risks to the wells at Aliso Canyon’s gas storage field. James Mansdorfer, Aliso Canyon gas field’s former storage engineer manager at SoCal Gas, wrote a letter to company officials warning that more than 100 gas wells could be sheared off should an earthquake on the Santa Susana Fault occur.

McNary joins AirTalk today, to recap the events since the gas leak was found, and what precautions are being taken for the future.

Guests:

Sharon McNary, KPCC reporter who’s been following the story

Matthew d’Alessio, associate professor of geology at Cal State Northridge; he has studied the seismic risks to the Aliso Canyon gas storage facility