On October 23, 2015 Southern California Gas crews discovered a massive leak in one of their natural gas storage wells at its Aliso Canyon storage field near Porter Ranch, California northwest of Los Angeles. Since October, the gas has been spilling out of a former oil field-turned-storage site at an initial rate of 44,000 kilograms per hour. To put that in perspective that is believed to be equal to roughly a quarter of the state's total methane emissions. Due to the fumes and smell permeating the area far 2,258 people have been placed in temporary housing and another 3,168 are in the process of finding temporary housing. Residents (and their attorneys- this is a prosperous area) have complained of inadequate accommodations and delays in finding temporary housing.
The leak is expected to be fixed by late February or early March according to information from Southern California Gas. To fix the problem, the gas company has drilled a relief well nearby. One of the challenges in drilling this relief well is to find a seven-inch pipe several thousands of feet below ground – while avoiding others nearby pipes. Using active magnetic ranging technology to target the drilling, Southern California Gas was able to identify the underground location of the leaking well, and is moving forward to connect the relief well to the leaking well. They believe that the two wells will intersect about 8,500 feet below ground. After they intercept the well they will pump heavy fluids and drilling mud into the bottom of the leaking well to stop the flow of gas up from its source, the reservoir. Once the flow of gas has been stopped, they will pump cement into the well to permanently seal the leak.
Natural gas is comprised mainly of methane, often 90% or more. Methane is an odorless and colorless gas that would not be noticed without odorants, in the form of mercaptans that are added so leaks can be detected. These odorants are not toxic at the levels found in the Porter Ranch community, but the odors have resulted in nausea, headaches and nosebleeds. Other constituents in the gas also have health impacts, such as benzene, although they have not been measured at levels that are considered a health issue.
Methane is the primary component of the natural gas being released from this leak. Methane in its gas form is an asphyxiant, which in high concentrations may displace oxygen especially in confined spaces. Decreased oxygen can cause suffocation and loss of consciousness. It can also cause headache, dizziness, weakness, nausea, vomiting, and loss of coordination. Skin contact with liquid methane can cause frostbite. Methane is also a major greenhouse gas and absorbs heat in the atmosphere, reflecting some of the absorbed heat back to the surface of the earth. Methane emissions represent approximately 10 % of all greenhouse gas emission in the United States. Methane is about 20-25 times more powerful than carbon dioxide in absorbing and keeping heat in the atmosphere. It stays in the atmosphere for approximately 9 to 15 years.
According to the U.S. EPA, methane is the second most prevalent greenhouse gas and accounted for about 10% of all U.S. greenhouse gas emissions from human activities. Methane is emitted by natural sources such as wetlands and the breakdown of organic material, as well as human activities such as leakage from natural gas systems and the raising of livestock. According to data collected by the California Air Resources Board, the well is currently leaking about 30,000 kilograms per hour down from a high of almost 58,000 kilograms an hour recorded in late November. The rate of methane released into the atmosphere should continue to fall.
The California Air Resources Board (ARB) has determined that some activated carbon/charcoal HVAC filters, plug-in air purifiers and in-line HVAC air cleaners should be effective in reducing indoor odors associated with the leak making it possible for residents who choose to stay in their homes. The agency is currently reviewing a range of models and has so far listed two plug-in models and one in-line HAVC model on its website. Southern California Gas is currently providing activated carbon/charcoal filters and plug-in air purifiers to residents of Porter Ranch, and are awaiting a new shipment of the in-line HVAC air cleaners from the manufacturer.
Historically, state laws have only stressed safety, reliability and affordability of service whenever implementing new rules and procedures for natural gas storage and distribution regulations. New laws now require the California Public Utilities Commission’s (CPUC) to work with natural gas distribution companies to determine the “most technologically feasible and cost-effective” strategies to avoid, reduce, and repair leaks as reasonably possible after discovery consistent with existing safety regulations and climate change goals. This does not allow the gas distribution companies to price into their gas fees the costs of planned preventive maintenance and system replacement program to avoid leaks.
To ensure the best use of ratepayers’ funds, gas distribution companies have to determine whether to appropriate infrastructure funds towards strategically replacing the sections of pipe its engineering studies have found to have a greater likelihood of leaking or towards addressing leaks that its experts have examined and deemed to be non-hazardous. In trying to keep ratepayers costs of gas low nationwide, we have failed to maintain the infrastructure, to stay ahead of well, equipment and pipe failure. We wait for failure before we fix it that is the wrong approach it allows the number of unrepaired, non-hazardous leaks to accumulate over the years and for wells and pipes to deteriorate to the point of failure before replacement. There will always be mistakes, components that appeared to still had some life in them that failed. All the costs of failure need to be weighed against the consequences of getting every last day of use out of a pipe or well. Prices for gas will need to go up so that distribution companies can maintain and replace the gas infrastructure before it fails, doing otherwise is unacceptable.
Update Note: In February Southern California Gas was able to temporarily stop the flow of gas while efforts continue to permanently seal the well.