Kern engineers brainstorm supercritical CO2 injections

Apr. 23—Anticipating a big ramp-up in local carbon management work, Kern petroleum engineers have begun looking at best practices for carbon dioxide injections to be done safely in local oil and gas wells as part of the county's push to become one of few national hubs for such work.

Representatives of oil and gas producers in the county huddled with national scientists Thursday to consider matters like how best to protect groundwater, prevent leaks and avoid inducing seismic events as they perform a profitable activity state and federal policymakers see as forestalling climate change.

Notes from the meeting of the local chapter of the American Association of Petroleum Geologists, shared Friday during a symposium hosted by Cal State Bakersfield, seem to confirm what proponents of local carbon dioxide removal had hoped — that Kern's workforce stands ready with relevant, specialized experience gained in local oilfield injection work.

Ensuring safety and containing pollution will be important as injection well-permit applicants work to win over impassioned skeptics in regulatory proceedings. Erik Bartsch, president and CEO of Aera Energy LLC, which had several employees at Thursday's meeting, said during an interview Friday the company "hears the concerns" regulators and other people have about carbon capture and sequestration, even as he adds, "the fact is that CCS is a proven technology."

"I think that as with any project we've got to be thinking clearly on how to work with regulators, how we work with communities to ensure the projects are behaving as intended," he said.

Slides presented Friday provided highlights of a workshop report but no detailed instructions on how carbon capture and storage facilities will work. The presentation was notable for the breadth of topics being tackled and the glimpse they give of active considerations.

The man who presented the notes Friday at the carbon management symposium, Creties Jenkins, a petroleum engineer with Rose and Associates in Santa Barbara, said the group looked at how careful attention might influence a range of possible outcomes.

The workgroup's focus was on critical issues thought to have the highest impact — manageable factors in which good engineering now could mitigate future risks, Jenkins said. He characterized the slides as recommendations for addressing potential concerns.

Topics listed for further attention were seismicity, faults and fractures, storage volume, injectivity, reservoir properties and integrity of new and existing wellbores. Jenkins said it will be necessary to fully understand the properties and effects of supercritical CO2, which is more dense, smaller and easier to store, and as well as what happens if it were to escape to a depth higher than the 3,000 feet below which it must be stored.

Other areas of focus should be phase changes, geomechanical issues, CO2 containment and trapping, seal capacity, well integrity, continuity and CO2 plume movement, according to Friday's presentation. Jenkins said it would be beneficial if operators could add wells allowing them to increase injection rates and direct the CO2 into multiple components.

"We need to identify those that have that sort of optionality," he said.

It will be important to study existing well records to see if there may be any potential problems with the facility. If they do, he said, operators must go in and seal the wellbores as a way of heading off potential leaks.

Answering a question from the audience about induced earthquakes, Jenkins said that although high-pressure water injections in Texas and Oklahoma were associated with seismic activity, he wouldn't expect substantial temblors at the relatively shallow depths proposed. His final comment on the matter was that it seemed possible to mitigate the risks.

He said there will also be need to work with people and get them "on board and comfortable with our intended actions."

Bartsch, reached after the presentation, noted there will be a public hearing as part of the Aera's application to the U.S. Environmental Protection Agency for a Class VI injection well permit, which he said has been certified as complete. He added that considerable review awaits.

"We are early in the process," he said.