State utility and gas regulators ignored a top gas manager's warnings about the risk of earthquakes to aging wells at the Aliso Canyon gas storage field when they okayed it to resume operations, Los Angeles County said Friday in court papers.
The county on Friday asked a Superior Court judge to block Southern California Gas Company from resuming operations at its Aliso Canyon gas storage field near Porter Ranch, site of the nation's largest-ever gas leak in 2015.
The Aliso gas field covers 3,600 acres in the Santa Susana foothills in northern San Fernando Valley. It is dotted by more than 100 wells. Most are more than 50 years old and began as oil wells converted to move gas in and out of depleted underground oil field. One of those wells ruptured hundreds of feet below the surface in late October 2015 and poured about 109,000 metric tons of natural gas into the atmosphere. Thousands of families relocated for months during the four months the gas leak was active.
The county's pleading includes an email that James Mansdorfer wrote in 2009 to company officials when he was storage engineering manager at SoCal Gas' Aliso Canyon gas field. In the memo, he notes that the more than 100 gas wells are vulnerable to being sheared off by a large earthquake on the Santa Susana Fault.
The wells operate at high pressure, they did not have "cathodic protection" which is used to control corrosion of metal parts that come into contact with gas. And at the time, SoCal Gas moved the gas in and out of the wells through both the center tube of the well and the donut-shaped space betwene the center tube and the casing of the well. That is a practice that, while common in the gas industry, has been outlawed by state regulators since the gas well blowout at Aliso.
Mansdorfer suggested SoCal Gas include in its 2012 rate increase request a budget for adding subsurface safety valves to all the wells below the level of the Santa Susana Fault. He noted that safety valves had failed in the past, but that newer safety valves worked better. He estimated the work could be done for up to $400,000 per well, all costs that could be written into customers' gas rates in 2012.
In 2012 Bret Lane, then senior vice president, wrote to Mansdorfer, "We will keep the Santa Susana issue out of the (rate case) for now."
Lane has since been named president and Chief Operating Officer of SoCal Gas.
Mansdorfer, whose job put him in charge of all the company's gas wells and storage reservoirs, left the company in 2015 to run a small oil business in Ventura County. He also works as a consultant and expert witness. Mansdorfer could not be reached for comment.
In April he wrote state gas regulators saying the Aliso gas field was seismically unsafe and that he had made repeated but unsuccessful efforts to get SoCal Gas to address the risk, but that SoCal Gas was assembling a team of experts to refute the seismic risk.
Mansdorfer's letter said a large earthquake, "would almost certainly sever the casing (and tubing) of every well, resulting in the release of gas at a rate 100 to 1,000 times" of Well SS-25, which broke open in October 2015.
At the time of Mansdorfer's letter, the gas regulators were going through the process of certifying the gas field to reopen.
Los Angeles County received the letter in June among documents it had requested of the state Division of Oil, Gas and Geothermal Resources.
"He has written to the state agency saying that he thinks the facility is unsafe and that there could be a big earthquake [that] could damage the facility and there could be a catastrophic result that all of the wells could rupture and leak not just one," said Deputy County Counsel Scott Kuhn.
The county's own Fire Department personnel had also warned of earthquake risk to the wells, and the county had asked the state to delay certifying the field safe to reopen until after a seismic safety study was completed.
The county also requests that a new environmental impact study be performed.
A SoCal Gas spokesman said the document was originally provided by the company to DOGGR, and that DOGGR considered the seismic issues in issuing its clearance for Aliso Canyon on Wednesday.
"While we do not agree with his position, safety concerns raised by current or former employees are taken seriously," wrote SoCal Gas spokesman Chris Gilbride. "For that reason, when this former employee informed us of his concerns last year, we shared the information with the state regulators."
The state Division of Oil, Gas and Geothermal Resources does not comment on litigation, said spokeswoman Teresa Schilling. She pointed to the responses the agency provided on Wednesday to prior public comments about the seismic risk at Aliso.
In that document the agency said it agrees that seismic studies are needed and that SoCal Gas will be required to cover the cost of a study by an outside neutral party. However such studies could take more than a year. The fact that gas reservoir and wells were not damaged in 1994 from the 6.7 magnitude Northridge earthquake, plus the equipment upgrades installed since the 2015 gas well blowout persuaded the agency that it need not delay reopening the gas field.