More than a hundred frightened local residents packed a room at the Porter Ranch Community School for three hours last week, looking for answers about the foul stench caused by a massive natural gas leak nearby. Southern California Gas Company’s Aliso Canyon natural gas storage facility has been leaking vast amounts of noxious gas into the air for two weeks, with still no end in sight.
Environmental health risks abound
The familiar rotten-egg smell of mercaptan – which utilities add to the normally odorless gas – hangs in the air for at least a mile, a pungent reminder of the potential health, safety and environmental risks of the uncontained airborne spill. Natural gas is mostly methane; a powerful pollutant that contributes to smog formation and global climate change, packing 84 times the warming power of carbon dioxide in the first 20 years it is in the atmosphere. Aliso Canyon is the largest natural gas storage site in the Western U.S., operating under intense injection pressures and holding huge amounts of methane.
Air samples around the site have found methane levels at some spots that are over 1,000 times normal background concentrations. The local air district documented 180 complaints of odors, and many people (including several children) have reported negative health effects like nose bleeds, vomiting and headaches. But company representatives and health department officials, who are doing regular air quality monitoring around the site and in the neighborhoods, assured the crowd there was nothing to worry about. The fact is, no one can say with any precision what the risks are, because nobody knows how much gas we’re talking about.
Clearly though, there have been detectable levels of toxic chemicals of concern in the air – adding even further evidence that this leak needs to be stopped. While officials maintain air samples taken to date show the leak does not present acute health impacts, known toxic chemicals are obviously being released and something in the air has been making many people near the site sick. It is a major inequity and potential public health concern to ask a whole community to breathe the soup of pollution coming from the Aliso canyon site.
A call for more data on methane
Having a leak go on for so long – in a state whose governor has declared war on climate change – should encourage researchers to kick into high gear to gather additional scientific data on methane. Any new work conducted as a result of the Aliso Canyon incident will complement the years of research conducted by the Air Resources Board, the Energy Commission, NASA’s Jet Propulsion Laboratory, and organizations like EDF to measure and model methane concentrations using airplanes, mobile ground level equipment, and satellites.
These efforts will, in time, allow researchers to understand more about methane modeling, and compare the results of various instruments and methods. Once the state’s research is concluded, it’s also likely that real-time measurements will be able to better determine the accuracy of industry estimates, creating a more complete picture of the methane emissions – both in the aggregate and for events like the one at Aliso Canyon.
Shedding light on the state’s aging natural gas infrastructure
There is a lot of uncertainty right now, but what we do know is that the crisis in Aliso Canyon is emblematic of the risks that exist as more and more of the state’s natural gas infrastructure ages.
For example, Aliso Canyon is an old oil field that was converted to a full time storage reservoir for natural gas back in the 1970s. The current crisis started with the failure of a 40-year-old pipe more than a thousand feet underground, which allowed pressurized field gas to flow back to the surface and into the air.
Decision makers know they have a serious infrastructure problem. SoCalGas recently asked regulators to approve a $200 million compressor retrofit and other upgrades at Aliso Canyon. Filings associated with the request, and the utility’s general rate case, reveal that the company has more than 50 storage wells that are over 70 years old.
How to close the regulatory gap
Aliso Canyon is a stark reminder that these aging systems, so crucial to our state’s energy system, need rigorous oversight using the best technology available. In letters to the California Air Resources Board and the Public Utilities Commission, Environmental Defense Fund has recommended key measures to close the urgent safety gap:
- First, there should be an accurate public accounting of the gas lost in pollution events like Aliso Canyon. Direct measurement during a release, both from the ground and in the air, will help first responders assess risk, and give neighbors the information they need to protect their families. Better data will also let officials evaluate long term climate impacts, and tally the cumulative effects of a failing system.
- Second, the state’s current approach to controlling methane emissions from oil and gas operations targets only the above-ground piping on natural gas storage sites, and ignores releases from subsurface malfunctions. Despite its huge climate impact, there are no rules requiring real-time methane detection, and no requirement for the purposes of methane control that below-ground leaks be fixed.
- Third, although rules and regulations address immediate public safety concerns, there’s no provision that directly limits the amount of methane a natural gas storage facility can emit. Based on the potential magnitude of this release, the state should evaluate direct regulations to limit the amount of methane that may be emitted to the air from natural gas storage fields.
- Finally, it appears that several factors may be at play here, potentially related to both geological and equipment conditions. As a result, we requested the gas company work with relevant state agencies to ensure a thorough analysis of the cause of the incident and geotechnical review of the site to prevent this type of incident from happening in the future.
One additional takeaway from this event involves natural gas storage as a whole. It is clear that natural gas storage, like that occurring at Aliso Canyon, is a critical resource for California’s economy and a necessary component of the state’s approach to creating a more responsive gas grid. But as this event illustrates, as important as storage is, the state needs to use all the tools at its disposal and the industry should use the best technology available to ensure storage is performed in a way that protects people and the environment.