This article was originally published by Floodlight, a non-profit newsroom that investigates the powerful interests stalling climate action.
On a November afternoon in 2022, a 57-year old well tapped into an underground natural gas storage reservoir in western Pennsylvania started leaking. The leak was fast enough that people a few miles away heard a loud, jet engine-like noise. Nearly two weeks later, the leak was stopped, but roughly 16,000 metric tons of methane had already escaped into the atmosphere. This was the equivalent of more than the annual greenhouse gas emissions from 300,000 gas-powered cars. The incident at the Rager Mountain gas storage field was the worst methane leak from underground storage since Aliso Canyon in California in 2015. This incident forced thousands of people from their homes, sickened many of them, and took four months to contain. Additionally, 35,000 plaintiffs in one class-action lawsuit were awarded up to $1.5 billion in damages in 2021.
According to a new report, there are thousands more potential opportunities for a similar situation across the country. The new analysis of data collected by federal regulators suggests there are as many as 11,446 storage wells in the country with the same key risk as the wells that failed at Rager Mountain and Aliso Canyon: They have only a single barrier to failure. All but one of Pennsylvania’s 49 gas storage fields has at least one potential single point of failure well, researchers found.
Methane leaks from gas storage are under increasing scrutiny in the United States and worldwide, as stopping them represents a relatively cheap and effective way to prevent greenhouse gas emissions. New regulations and fees are being put in place to cut methane leaks, including a requirement for baseline risk assessments on all wells by 2027, new EPA rules on methane leaks and repair, and a planned federal fee on “waste” methane. However, industry groups have pushed back against the fee, arguing it would harm smaller oil and gas companies and discourage oil and gas production overall.
The Rager Mountain leak was caused by a break below ground in one well’s casing — the barrier between where pressurized gas flows and the geology around it. The well had become heavily corroded from exposure to water, air, and organic matter through an open valve, according to a third-party analysis. Many of these wells are decades-old and not originally designed for storage. They have gone through the stresses of repeated cycles of injecting and withdrawing gas. The number of wells with potentially only one barrier was three times larger than previously estimated before the Pipeline and Hazardous Materials Safety Administration (PHMSA) data became available.
While Equitrans, the owner of Rager Mountain, had its own risk ranking of storage wells, and recognized that corrosion was an issue, the blowout still occurred. In the wake of the incident, Pennsylvania’s Department of Environmental Protection said it was considering a “top to bottom review” of the state’s gas storage industry.
Overall, the methane leak at Rager Mountain highlights the need for attention to the well integrity at storage fields to prevent future incidents. This is an issue that has caught the attention of federal and state regulators, as well as industry stakeholders.
