Porter Ranch Gas Leak Linked to California's Broken UIC Program

For more than two months, Southern California Gas's Aliso Canyon underground storage facility in the Porter Ranch neighborhood of Los Angeles has been leaking massive quantities of natural gas into the soil and air. A well failure discovered there on October 23 is the latest in a long string of problems related to California's inadequate and outdated Underground Injection Control (UIC) Program.

Tens of thousands of families live in the Porter Ranch neighborhood and have been affected by this leak, and thousands have been temporarily relocated. In addition to the health threats posed by this leak (see my colleague Miriam Rotkin-Ellman's blog on this), methane, the primary component of natural gas, is a powerful heat-trapping pollutant that helps drive dangerous climate change.

According to preliminary estimates from the California Air Resources Board (CARB), total leakage from the Porter Ranch facility as of December 23rd is equivalent to the yearly greenhouse gas emissions from more than 480,000 passenger vehicles, and the leak is likely to continue for months. In a letter to Governor Brown, SoCalGas has committed to mitigating the environmental impact of the gas released from the leak. In meeting this pledge, it is incumbent on SoCalGas to obtain and retire carbon allowances under AB32, California's landmark greenhouse gas emission reduction program, equal to the total greenhouse gas emissions associated with the leaked methane.

Many questions remain about the exact cause of the well failure, which likely won't be answered until the well is brought under control. What we do know is that this well is regulated under the flawed Underground Injection Control program run by the California Division of Oil, Gas, and Geothermal Resources' (DOGGR). This is the same program under which thousands of wells are improperly injecting oil and gas wastewater and other fluids into federally protected drinking water aquifers. And it's the same program plagued by systemic problems including poor recordkeeping, inadequate staffing, and failure of regulators to perform crucial, required tests to ensure that injection wells are mechanically sound.

The failed well is also quite old. Originally drilled in 1953 as an oil production well, it was converted to a gas storage well in 1973 - before the UIC program even existed. Well construction practices have evolved significantly in that time, but the well has not been updated. It's possible that the outdated construction - in particular the lack of cement behind the piece of casing that failed - caused or contributed to the leak. Regulators also reported that a safety valve near the bottom of the well broke in 1979 and was never fixed. If the valve was operational, it may have been easier to stop the leak.

(click to enlarge)

The real problem is that all of this - uncemented casing and broken valves - is allowed under California's outdated, inadequate UIC regulations.

The well's construction wasn't updated and the valve wasn't fixed because neither safety measure was required. In fact, California's UIC rules don't include any standards for well construction. None.

If a brand new gas injection well is drilled today, there is nothing in the rules to prevent it from being built exactly the same way as the Standard Sesnon 25. And tests used to ensure that wells are in good condition, called mechanical integrity tests, have to be performed only once every five years.

While a leak of this magnitude from a storage well is apparently uncommon, we need better monitoring - in California and nationwide - to make sure we really know what leak rates are. We'll need a thorough investigation to identify its exact cause and how it could have been prevented. However, it's clear that the program under which these wells are regulated is totally inadequate and there's little in the current rules that could prevent such an accident from happening again.

DOGGR has announced a plan to overhaul the UIC program. This latest incident further highlights just how urgently that reform is needed. Ultimately, this crisis also demonstrates the need to move away from fossil fuels to clean and renewable sources of energy.

About the Authors

Briana Mordick

Senior Scientist, Land & Wildlife and Climate programs

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