DALLAS, TX (TIP): New federal rules designed to reduce smog in the country’s national parks will force seven of Texas’ oldest coal plants to make costly upgrades to their smokestacks.

With an eye to lifting the haze that hangs over Big Bend National Park and other federal parks and wilderness areas, the U.S. Environmental Protection Agency released new air pollution standards Wednesday for Texas – one of a handful of states that had continued to resist government efforts to cut down on the release of visibility-impairing sulfur dioxide.

Experts were wary Wednesday of predicting what exact impact the rules would have on the state’s coal power industry, which is already struggling under a natural gas boom that has forced power prices down. But last week the state’s grid operator, the Electric Reliability Council of Texas released analysis of a draft of the haze rule published by the EPA last year.

In that report, ERCOT predicted when combined with President Obama’s order to reduce carbon emissions from the power sector as much as 4,700 megawatts of coal capacity could be shut down – roughly a quarter of the current fleet.

“We’re still in the process of reviewing, but it looks like it’s aligned almost identically with what the EPA put out in December last year,” said Joshua Smith, an attorney with the Sierra Club. The biggest loser under the new rules is the Dallas power generator Luminant – a subsidiary of bankrupt Energy Future Holdings. Its Big Brown, Monticello, Martin Lake and Sandow facilities will now all be required to either install scrubbers or upgrade their existing equipment.

Also named were NRG Energy’s Limestone plant, Xcel Energy’s Tolk facility and the Coleto Creek power plant southeast of San Antonio. All together the facilities comprise 14 separate coal-fired generation units – nine of which are owned by Luminant. Each has between three and five years to comply, depending whether they were installing all new scrubbers or simply retrofitting. Luminant said it was still reviewing the rules Wednesday but attacked the EPA as overstepping its authority.

The haze rules “would require Texas to spend $2 billion for what EPA itself projects would be no perceptible improvement in visibility,” said spokesman Brad Watson.

The tighter standards come as conditions in many national parks continue to worsen.The National Park Service maintains a running camera in Big Bend, allowing visitors to its website to see the often hazy view across the desert there.

“Unfortunately, pollution is destroying the very scenic resources many people seek. Generally, park visitors find moderately hazy views on most days, with poor conditions of less than 30 miles visibility 6% of the time,” the website says.

Efforts to tighten visibility standards in U.S. wilderness began with a 1990 amendment to the Clean Air Act. But bureaucracy and state opposition dragged the process out for decades. Texas finally submitted a plan to comply six years ago, but it was rejected by the EPA as effectively toothless.

Ever since, the EPA has been working on its own plan for the Lone Star state – along with plans for Arkansas and Louisiana, which have also resisted, Smith said.

“Many states have already started implementing plans that involve [pollution] controls identical to this. These are common across the industry,” he said.

Texas Attorney General Ken Paxton, like his predecessor, has made a point of resisting federal attempts to impose environmental safeguards. In October, he sued the EPAover Obama’s plan to cut carbon emissions from the power industry, part of a 24-state coalition. A spokesperson for Paxton said his office was still reviewing the new rules.

DALLAS (TIP): Stormy weather in Texas has snarled flights at Dallas/Fort Worth, creating headaches for travelers flying to, from or through that busy U.S. airport on Friday.

More than 420 flights – about 180 departures and 240 arrivals – had been canceled there as of 3:50 p.m. ET, according to flight-tracking service FlightAware. That represented about 20% of the airport’s entire daily schedule. And another 600 of Friday’s flights had been delayed. Together that represents about half of the day’s flights at DFW, according to the FlightAware data.

DFW, of course, is the biggest hub for American Airlines, now the world’s biggest airline following its merger with US Airways.

Flight delays also were being reported at Dallas Love Field, the smaller of the two Dallas-area airports. Southwest operates a major base from Love Field.