Like an old racehorse, the West Seminole oilfield, a 12-square-mile patch of dirt on Texas’s far western flank, has been trudging along for years, kept kicking by an elixir its jockey shoots into its rump.

On a recent afternoon, as storm clouds blanketed the field and a winter wind howled, dozens of rusty pump jacks rocked up and down, groaning with each revolution as they sucked out more black gold. The drug that the field’s operator, Occidental Petroleum, injects into West Seminole loosens the oil in the stone beneath the sagebrush—forcing from the rock ever more of the hydrocarbon treasure locked inside its geologic pores. The magic medicine is an old industrial gas with a new image problem: carbon dioxide.

For decades, Occidental has been pumping massive quantities of CO₂ into the ground, juicing the flow of oil in aging fields that have lost the oomph nature originally gave them. The CO₂ frees more oil to rise to the surface, where it can be sold and burned. The petroleum industry has used this turbocharging technique—called “enhanced oil recovery”—elsewhere. But Houston-based Occidental is a global expert. Across thousands of square miles of eastern New Mexico and western Texas, on the iconic swath of land called the Permian Basin, the company nicknamed Oxy has built a multibillion-dollar web of infrastructure to manage vast quantities of the CO₂. The Permian rocks’ structure makes them particularly giving of their oil when their spongelike holes are coaxed with the greenhouse gas in liquid-like form.

Now, amid rising consumer anger about global warming and ballooning government subsidies for companies working to solve it, Oxy is attempting a stunning CO₂ pivot. It hopes to stop pumping into its fields CO₂ extracted from the earth, and instead deploy CO₂ sucked from man-made sources: from power plants, factories, and even thin air.

The company’s ambition is to build into a core business a process that has long been little more than a science project: “carbon capture and storage,” or CCS. It involves chemically snagging CO₂, typically as it’s wafting out of smokestacks but also from ambient air itself, and then injecting it into subterranean rocks. The goal: Rather than continue to dump CO₂ into the atmosphere, where it’s thickening a chemical blanket that’s warming the earth, humanity can bury it underground, ostensibly forever.

Countless difficulties imperil the CCS dream. Influential environmentalists oppose it, arguing it diverts attention from renewable energy. Beyond principle, technical dilemmas loom. One, now fueling a technological race, is how to slash the cost of capturing CO₂, which remains too expensive to work without subsidy. Another, now evolving into a high-stakes lobbying fight, is how far regulators should go in forcing oil companies to prove that CO₂ they’re sending into rock stays safely where it’s put.

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