"The largest U.S. oil refiners released tons of air pollutants into the skies over Texas this past week, according to figures provided to the state, as refineries and petrochemical plants in the region scrambled to shut production during frigid weather."

"Late last year, as winter approached and power companies prepared for cold weather, Gov. Greg Abbott’s hand-picked utility regulators decided they no longer wanted to work with a nonprofit organization they had hired to monitor and help Texas enforce the state’s electric reliability standards."

"Federal regulators warned Texas that its power plants couldn’t be counted on to reliably churn out electricity in bitterly cold conditions a decade ago, when the last deep freeze plunged 4 million people into the dark."

"One of the nation’s premier nuclear laboratories isn’t taking the necessary precautions to guard against wildfires, according to an audit by the U.S. Energy Department’s inspector general."

"The Mexican wolf was hunted to the brink of extinction. But as it is reintroduced, conservationists hope to quell the old enmity between 'el lobo' and the farmer. "

"The Navajo Nation’s Department of Justice announced Wednesday it has settled with mining companies to resolve claims stemming from a 2015 spill that resulted in rivers in three western states being fouled with a bright-yellow plume of arsenic, lead and other heavy metals."

"A string of explosions involving little-regulated petroleum and chemical storage tanks have lawmakers and regulators talking about new rules as the Legislature prepares to convene this month."