Why a natural gas storage climate ‘disaster’ could happen again

This story was initially printed by Floodlight, a non-profit newsroom that investigates the highly effective pursuits stalling local weather motion.

On a November afternoon in 2022, a 57-year old well tapped into an underground pure fuel storage reservoir in western Pennsylvania began leaking, quick sufficient that folks just a few miles away heard a loud, jet engine-like noise. 

By the point the leak was stopped almost two weeks later, roughly 16,000 metric tons of methane had escaped into the environment, the equal of greater than the annual greenhouse fuel emissions from 300,000 gas-powered automobiles.

The blowout of a properly on the Rager Mountain fuel storage area was the worst methane leak from underground storage since Aliso Canyon in California in 2015. That incident pressured 1000’s of individuals from their houses and sickened lots of them, taking 4 months to include. In 2021, 35,000 plaintiffs in a single class-action lawsuit were awarded up to $1.5 billion in damages. 

Whereas not as massive or imminently harmful to residents, the Rager Mountain leak was a “disaster,” in accordance with one Pennsylvania regulator. Bloomberg labeled it america’s worst climate disaster that year. 

The pure fuel that leaked methane in Pennsylvania and California shouldn’t be saved in tanks however in large underground geological formations accessed by a number of wells. There are about 400 such storage fields throughout 32 states.

In response to a brand new report, there are 1000’s extra potential alternatives for the same scenario throughout the nation. The new analysis of data collected by federal regulators suggests there are as many as 11,446 storage wells within the nation with the identical key danger because the wells that failed at Rager Mountain and Aliso Canyon: They’ve solely a single barrier to failure.

“That inhabitants is lots bigger than we had estimated, or different researchers had estimated with state [data],” says Greg Lackey, an creator on the research and researcher on the Division of Power’s Nationwide Power Expertise Laboratory. 

All however considered one of Pennsylvania’s 49 fuel storage fields has at the least one potential single level of failure properly, researchers discovered.

Pure fuel is primarily made up of methane, a greenhouse fuel 80 instances extra highly effective than carbon dioxide within the short-term. Methane leaks from oil and fuel infrastructure are below growing scrutiny in america and worldwide, as stopping them represents a comparatively low cost and efficient strategy to stop greenhouse fuel emissions, the first trigger of worldwide warming.

Leaks from fuel storage are just one a part of the trade’s methane drawback. Such services are also prone to dramatic blowouts which are laborious to regulate as a result of they’re linked to massive, pressurized reservoirs of fuel. 

New guidelines, charges goal to chop methane leaks

Laws put in place on fuel storage post-Aliso Canyon are nonetheless rolling out, together with a requirement for baseline risk assessments on all wells by 2027. New EPA guidelines on methane leaks and restore and a deliberate federal charge on “waste” methane would impression fuel storage as properly. 

The charge, which continues to be being finalized, would pressure corporations to finally pay as much as $1,500 per metric ton of methane in extra of the equivalent of 25,000 metric tons of carbon dioxide, a threshold the Rager Mountain leak meets virtually 20 instances over. Business teams have pushed again in opposition to the charge, arguing it will harm smaller oil and gas companies and discourage oil and gas production overall.

Many of those wells are decades-old and never initially designed for storage. They’ve gone by way of the stresses of repeated cycles of injecting and withdrawing fuel. Some, like Rager Mountain, are in comparatively rural, sparsely-populated areas, however others are near neighborhoods in Pennsylvania, Ohio and California. 

The Rager Mountain leak was attributable to a break under floor in a single properly’s casing — the barrier between the place pressurized fuel flows and the geology round it. The properly had turn out to be closely corroded from publicity to water, air and natural matter by way of an open valve, in accordance with an third-party analysis submitted to regulators and obtained through a public records request.  

“They in all probability didn’t notice it, however they had been creating an optimum case for corrosion,” says Dan Arthur, president of the engineering and technical providers agency ALL Consulting, who reviewed the evaluation. 

Arthur says older wells in storage fields haven’t been given “as a lot significance” as they need to be, and operators want to ensure they’re totally addressing properly integrity.

“Age is a danger issue that you need to contemplate, however it additionally will depend on how you’re caring for the properly,” he says. Redundant obstacles cut back the danger of methane escaping if the properly casing fails, Arthur and Lackey say.

Minimal federal security requirements on underground storage fields had been set lower than a decade in the past within the aftermath of the Aliso Canyon leak. One of many federal companies in control of regulating fuel storage websites, the Pipeline and Hazardous Supplies Security Administration (PHMSA), solely started accumulating common information on underground storage fields in 2017.

Extra information wanted to establish riskiest wells

The variety of wells with doubtlessly just one barrier was three times larger than previously estimated earlier than the PHMSA information turned out there, Lackey says. This “single level of failure” design featured in each Rager Mountain and Aliso Canyon blowouts is current in as many as 64 % of all fuel storage wells in america, his analysis discovered.

However the information reported to PHMSA shouldn’t be sufficient to verify what number of of those wells even have a single level of failure that might flag wells on the highest danger of one other blowout, Lackey says. Researchers would wish extra details about every properly’s design and development, he says.

“What you don’t get perception into is what number of different casings there are, or the place the places of cement are,” Lackey says, describing further obstacles that might decrease the danger.

Rager Mountain’s proprietor and operator, Equitrans, had its personal danger rating of storage wells, according to the third-party analysis. Whereas Rager is the corporate’s largest area in Pennsylvania, its wells weren’t the very best ranked within the firm’s personal danger administration plan — others had been larger up the checklist due to their proximity to residential areas.

Each Peoples Pure Gasoline, the earlier proprietor of the sector, and Equitrans “acknowledged that corrosion was a problem,” so the businesses used probes, often called “logs,” to look at the integrity of the properly casings. However, the evaluation famous, “Such a method depends on the logging being fairly correct.”

A 2016 take a look at of the casing wall of the properly that finally failed underestimated its corrosion, the report says. When Equitrans reran the take a look at after the blowout utilizing an up to date algorithm, it confirmed way more corrosion.


Within the wake of the Rager Mountain blowout, Pennsylvania’s Division of Environmental Safety, mentioned it was contemplating a  “high to backside evaluate” of the state’s fuel storage trade. Pennsylvania is considered one of a handful of states which have their very own laws overlaying fuel storage. 

“Every little thing is on the desk for consideration by way of ensuring this trade is regulated appropriately and the general public is protected and the atmosphere is protected against potential incidents like this taking place once more,” mentioned Kurt Klapkowski, performing deputy secretary for DEP’s Oil and Gasoline Administration workplace, a month after the incident.

‘An enormous battery system’

However after a profitable effort by Equitrans to maneuver the majority of the incident investigation to federal regulators, DEP seems unsure or unable to maneuver ahead with such a evaluate. Klapkowski instructed the company’s Oil and Gasoline board in September that regulators had been “attempting to determine the place our jurisdiction ends or is perhaps preempted by the federal authorities.”  

Pennsylvania DEP’s investigation into surface and groundwater contamination at Rager Mountain is ongoing, the company mentioned in an emailed assertion, and it “stays dedicated to its objective of inspecting storage area wells on an annual foundation no matter danger.” 

Wells are assessed by way of floor inspections and data reported by operators, DEP added, utilizing a number of elements to prioritize wells for inspection, together with the potential environmental impression and chance of failure, in addition to proximity to inhabitants.

Equitrans has taken a number of steps to cut back danger in its storage fields, spokesperson Natalie Cox mentioned in an emailed assertion. They embody reprocessing older properly assessments, working further assessments on one other 100 wells in 2023, and altering its necessities for when so as to add protecting gel to cut back corrosion. The corporate didn’t reply questions on whether or not these assessments led to any properly replacements. 

Lackey’s research additionally discovered that nationally, whereas most leaks from fuel storage had been linked with accidents or properly enchancment tasks often called workovers, leaks from corrosion launched a a lot bigger quantity of methane.

“If it’s a valve or one thing that’s damaged off on the wellhead, that is perhaps simpler to include, somewhat than one thing downhole that might be uncovered to larger pressures throughout the properly,” he says. “Throughout workovers you could have programs in place to include the properly … whereas with corrosion, that’s one thing happening silently within the background.”

Whereas a 2016 government task force really useful phasing out single level of failure of wells, in the end the federal minimal requirements solely required operators to deal with them by way of submitting risk-management plans to federal regulators — plans that aren’t public. 

The discharge of fuel from Rager Mountain in November 2022 represented about 15 % of the sector’s working storage quantity. Underground storage fields act as “an enormous battery system,” says Drew Michanowicz, a researcher who has studied their proximity to residential areas. 

Main leaks from storage not solely launch large volumes of greenhouse gases but in addition cut back reliability in areas the place pure fuel dominates house heating and electrical energy manufacturing, Michanowicz says.

The federal leak investigation at Rager Mountain stays open at the least till regulators evaluate work on fixing three briefly plugged wells within the area, doubtless within the spring. However Rager Mountain is in any other case working. In October, with PHMSA’s approval, Equitrans started injecting fuel into the sector for the winter. 

This story was produced with assist from the Fund for Investigative Journalism.