"EPA offered a steady defense today [Tuesday] of Obama-era ozone standards the agency previously considered scrapping.

During long-awaited oral arguments at the U.S. Court of Appeals for the District of Columbia Circuit, government lawyers defended the agency's 2015 thresholds for the air pollutant as "forward progress" aimed at protecting vulnerable people.

"The revised ozone standards here represent notable forward progress in protecting the health of all Americans across this country," Justice Department attorney Justin Heminger told a three-judge panel this morning."

"The parking lot at the Settlers Ridge Wave Pool just outside of Pittsburgh is dotted with camping chairs. The people sitting in them are looking up at the sky, as if they’re waiting for a fireworks show to begin. But it’s 8:00 a.m., and this group is here for the ‘visible emissions observer certification and training program.’"

"Two of acting EPA chief Andrew Wheeler's appointees to a prominent advisory committee are pushing back against his recent decision to disband an auxiliary panel involved in a closely watched review of airborne particulate standards."

"The Trump administration’s proposal to roll back fuel economy standards relies on an error-ridden and misleading analysis that overestimates the costs and understates the benefits of tighter regulation, an independent study by leading economists, engineers and other experts has found."

"When EPA begins a major review of air pollution standards this week, a researcher who has received funding from an industry group opposed to the rules will be leading the agency's panel."

"The Trump administration wants to remove a key barrier to constructing new coal-fired power plants in the U.S. -- but don’t expect any utilities to actually build them."

A deep look at the Mexican city of Mexicali shows a pattern of unchecked pollution leading to illnesses and deaths on both sides of the border.

"The White House's regulatory shop has completed its assessment of a hot-button ozone rule, putting EPA on track to issue the final version by tomorrow's [Thursday's] court-ordered deadline."