Zombie Wells, Part 3: Sinkholes near old Texas oil wells may signal issues in climate change fightHouston ChronicleMedia Coverage | Jul 18, 2023

The gas used in some oil fields to stimulate oil production has already found its way to the surface through old wells. In one notable case in southern Wyoming in 2016, carbon dioxide, methane and volatile organic compounds leaked into a school, forcing it to temporarily hold classes at a different site while several wells were plugged, according to a study by the Natural Resources Defense Council, an environmental advocacy group.

Compounding the problem, cement plugs could corrode when salt water and carbonic acid — the chemical result of carbon dioxide mixed with water — sloshes around underground. Even the slightest crack can accelerate corrosion, said Birol Dindoruk, endowed professor of petroleum engineering and chemical and biomolecular engineering at the University of Houston. He said lawmakers and regulators should have strict policies regarding how close carbon storage areas can be to old wells and there should be ongoing monitoring to stay on top of corrosion and leaks.

“Looking at these wells, evaluating them and taking care of them is extremely important for carbon sequestration,” Dindoruk said. “I think we need to do our homework.”

What we don’t know might hurt us

Kitty Shivers Key, 78, remembers when oil money flowed into Daisetta. There were 10 beauty parlors in town when she was growing up in the 1950s, she recalled. Now, the town doesn’t even have a restaurant and the nearest grocery store is 15 miles away.

It confounds Key, a lifetime resident of the Daisetta area and informal town historian, that people in her community still lack basic information about what is going on under their community. She suggested the sinkhole be converted into a ticketed tourist destination to raise funds for more research.

What frustrates her most, though, is the truth at the bottom of the sinkhole likely isn’t as bad as it might seem.

“No matter what the doctor tells you,” she said, “it could not be as bad as you could imagine.”

Transparency is important, she said. Key and her husband used to run a well-plugging firm. At one point, she said he headed to Austin in a failed attempt to convince the Legislature to require deeds to document the existence of wells on a property.

Transparency in real estate transactions is one of many failed policy pushes surrounding the issue of orphaned wells, said Adam Peltz, a director and senior attorney in the Environmental Defense Fund’s energy program. He said more work should be done to monitor wells, to quantify the cumulative emissions coming from unplugged wells and to study impacts of leaking wells on groundwater. Wells should be closely monitored to ensure they aren’t leaking, especially as carbon storage takes off.

“It’s one thing if you know about the orphan well. Then at least you can do something about it,” he said. “If you don’t know about it, surprise! You have a geyser.”

More money, fewer problems

The single best way to address the overall problem of orphan wells, Peltz said, is to require companies to pay additional bonds for marginal wells — the low-producing wells often sold to small companies once an oil major has decided they are no longer worth keeping. These are the wells are most often orphaned when small firms go bankrupt or simply shut down and move on, sticking taxpayers with the cost of plugging.

Instead of allowing an oil major to sell the low-producing wells to a smaller firm without intervention, Peltz suggested regulators require a hefty bond as part of the transaction: $75,000 per well. If the firm plugs the well, the government gives the money back. If the firm doesn’t plug the well, the government has the money to do the work.

Texas already requires bonds from operators, but the amounts are small compared to the liability, Peltz said. Even Texas, “which has by far spent the most money on well closure,” is short on funds needed to fix the problem.

“The blanket bonds are not risk-tailored and the dollar amounts are small,” Peltz said, “so you have this problem where small operators who are not well-financed can have relatively small bonds for relatively large numbers of wells. And that puts state taxpayers at risk.”

Another route could be to incentivize well-plugging by offering companies carbon credits for plugging inactive wells, said Dan Arthur, president and chief engineer of Tulsa, Okla.-based ALL Consulting, who has decades of experience working with aging wells and the challenges they pose. “Those liabilities are so much that you’ve got to provide incentives to plug these wells.”

Reckoning with past and politics

Roughly 80 percent of the orphaned wells are not creating problems, industry observers and scientists interviewed for the story said. But the ones creating problems tend to be significant and clustered in certain areas.

That’s why government-run well-plugging programs should also rethink the way they go about plugging wells in aging fields, Arthur said. Wells in a field should be evaluated and plugged as a single unit in the same way they were developed by oil producers. To continue doing it piecemeal can create more headaches, he said.

“Let’s say you have a little field that’s 10 wells. Plug one and it may cause another one to be a problem,” he said. “They don’t get developed one well at a time.”

Changing the strategy would require a thorough examination of orphaned wells. Doing it right would take more time than a single election cycle, he said.

“They want to plug these for political gain. The states are under massive pressure,” he said, noting a one-year deadline to use initial disbursements of federal well-plugging funds that expire next year. “In an ideal world, you’d want to do these things, to identify the problem areas, the problem wells, check ‘em out.”

Certifying that the plug jobs are done correctly would be yet another step, he said. “That takes extra time and money.”

Ganesh Thakur, distinguished professor of petroleum engineering and director of energy industry partnerships at the University of Houston, agreed that the federal government should commission studies to identify and prioritize which wells should get plugged, and when.

“If these orphaned wells are identified properly and they are prioritized and we can focus on those which are the largest culprits, we can make big progress in this area,” he said.

Moving forward, he said, wells should be plugged to the highest standards, using the highest quality cement and steel, to preserve the environment and protect the future of the industry. Carbon dioxide is more corrosive than saltwater, oil and gas, and it can more freely move through cracks and leaks, he said. Only after the nation contends with its problem wells can carbon storage be a viable path forward in the fight against climate change.

“It is not the problem of only one operator. It is the problem of the state; it’s the problem of the public — you and me  — and it’s the problem of the federal government,” he said. “We all need to work together. Because things are not going to become better with time. Things are going to get worse with time.”

This story is the third in a three-part series. Read Part 1 here and Part 2 here.