The most important pollution rule you’ve never heard of

It’s the most important air pollution rule you’ve never heard of. And its benefits to air quality and health could extend far beyond its stated purpose — if it isn’t gutted by a Republican-led Congress or Environmental Protection Agency (EPA).

Despite its obscurity, the Regional Haze Rule is nothing new. It was issued by EPA in 1999, and updated under President George W. Bush in 2004. In fact, I worked on the early stages of a regional haze plan for Georgia over a decade ago as a fresh-out-of-grad-school hiree.

The rule aims to improve visibility at 156 national parks and wilderness areas nationwide. That includes making the Great Smoky Mountains a little less smoky, and protecting Guadalupe Mountains and Big Bend National Park here in Texas and the Wichita Mountains Wilderness in Oklahoma. Clearer skies are welcomed by outdoor enthusiasts like me who enjoy hiking, kayaking and other pursuits in our nation’s most scenic areas.

Clearing the haze also protects the health of millions of Americans who may never visit those sites. That’s because the same pollutant that causes haze —fine particulate matter — is also the deadliest air pollutant. Since pollution transcends boundaries, cleaner air in our national parks means cleaner air for all of us to breathe.

Like most Clean Air Act provisions, the haze rule tasks states with developing control plans and EPA with approving them. Most states are already benefitting from cleaner air under EPA approved plans. For example, in Georgia, all the largest coal power plants have installed scrubbers or converted to natural gas. Controls like these have contributed to sharp declines in sulfur dioxide and particulate matter throughout the eastern United States.

However, Texas and Oklahoma issued plans that EPA found to be inadequate, prompting EPA to issue its own plans for the states. In Oklahoma, it was Attorney General Scott Pruitt (R) who sued the EPA to block its tougher plan. Pruitt lost his case, but now has been nominated by President-elect Donald Trump to lead the agency he sued.

Despite Pruitt’s lawsuit, Oklahoma utilities are acting to clean up their power plants. Oklahoma Gas and Electric is converting the state’s largest coal plant to natural gas and adding scrubbers to another. The Public Service Company of Oklahoma chose instead to close its coal plant.

Here in Texas, prospects for cleaning up our dirtiest coal plants are, well, up in the air. Our own attorney general convinced the Fifth Circuit Court to block EPA’s haze plan for the state. However, that ruling didn’t negate the need for the state’s oldest plants to install what’s known as Best Available Retrofit Technologies.

{mosads}Earlier this month, the EPA specified what those technologies should achieve at Texas power plants. The EPA’s proposal would require new or improved controls at nine of the state’s highest emitting coal plants.

Those coal plants, each at least four decades old, are why Texas leads the nation in sulfur emissions. By my calculations, meeting the EPA’s limits at those nine plants alone would cut power plant emissions statewide by more than half. In fact, unscrubbed coal plants emit 20 times the sulfur of plants with modern controls.

Those sulfur emissions are leading contributors to both the haze that clouds our scenic areas, and the particulate matter that harms our health. That’s why the health benefits of cleaning up sulfur pollution are typically over 10 times the costs.

Though scrubber costs are dwarfed by their health benefits, they can provide a tipping point to accelerate coal closures. Economists estimate that most Texas coal plants are unprofitable even without modern controls, as cheap natural gas and wind push down power prices statewide.

The Texas grid operator ERCOT is already preparing to ensure power reliability is maintained as coal plants close, and expects solar will replace most of the retiring coal. The Brattle Group projects that coal may fall to 6 percent of Texas electricity by 2035. Shifting from coal to solar means avoiding not just sulfur but also smog-forming nitrogen oxides, planet-warming carbon dioxide, and intense water use and pollution.

Those benefits are now in jeopardy under the new administration. One scenario would be for a Pruitt-led EPA to withdraw its proposed rule for Texas. However, that would be certain to prompt lawsuits from environmental groups, since the EPA applied routine modeling and proposed sulfur limits consistent with those required in other states.

The greater risk is that Republicans in Congress may seek to scrap the Regional Haze Rule entirely. The rule is among over 200 regulations targeted by the House Freedom Caucus, including energy efficiency standards, water protections, and limits on nitrogen, sulfur and ozone pollution. The air quality limits are in earlier stages of being achieved than the haze rule, and are thus more vulnerable to withdrawal.

For all the attention on whether Trump and fellow Republicans accept climate science, the Freedom Caucus hit list reminds us that air quality, water quality, energy efficiency and health are also at risk from politicians hostile to environmental protections.

The Regional Haze Rule is just one of the many fronts on which battles will be waged in the quest for clearer, cleaner air and a healthier environment.

Daniel Cohan is associate professor of civil and environmental engineering at Rice University.

The views expressed by contributors are their own and not the views of The Hill.