The BRAVO researchers made their results public this past September. The short version? Don’t blame Mexico. In fact, the park’s worst haze comes from the eastern United States and East Texas. Mexico’s Carbón I and II plants remain the biggest single contributors to Big Bend’s sulfate haze. But on the haziest days, they contribute just 9 percent of the total, and the rest of Mexico another 7 percent. Texas adds 11 percent, the eastern United States 22 percent and the western United States 4 percent. The rest of the haze arises from windblown soil, smoke from agricultural and forest fires, manufacturing activities and vehicle exhaust. Mark Scruggs, assistant chief in the National Park Service’s air resources division, which monitors pollution in the parks, says the big surprise was how much sulfate originates in the eastern United States, borne on prevailing winds that blow across East Texas or loop down to the Gulf of Mexico and north through the Mexican mainland. Mexican officials had been arguing since 1996 that Big Bend’s problems came from north of the border—including a string of power plants along the Ohio RiverValley—but the Americans were skeptical until the BRAVO data came in.
Ever since Congress created the first national park, at Yellowstone in 1872, the parks have enjoyed special legal protections. In 1916, the National Park Service was set up to maintain areas “unimpaired for the enjoyment of future generations.” Additional legal backing came in 1977 when amendments to the Clean Air Act gave parks the highest priority, designating them as Class I areas. The law is emphatic: “Congress hereby declares as a national goal the prevention of any future, and the remedying of any existing, impairment of visibility in mandatory class I Federal areas which impairment results from manmade air pollution.”
“It was visionary to try to protect these areas without even knowing how difficult it would be,” says air resources division director Chris Shaver. The division has outfitted most major parks with filters to gather aerosols, or ultrafine solid and liquid particles in the air; nephelometers to measure how haze scatters sunlight; and transmissometers that gauge scattering and absorption of light by pollution, dust, mist or other material in the air. Chemical samplers scrutinize the concentration of such problematic molecules as ozone, which can be harmful to humans at ground level.
Shaver remembers standing on the rim of the Grand Canyon with her then 6-year-old daughter, Courtney, in 1990. The girl looked at the barely visible cliffs on the other side and said, “Mom, I don’t know how to tell you this, because I know how hard you are working, but you’re not doing a very good job.” Courtney graduated from college this year, and Shaver still sees haze in the park system. When researchers started measuring the Grand Canyon’s air quality in the 1970s, “Congress and most people thought we had a problem with [only] a few power plants in the four corners,” she says of the region where Arizona, New Mexico, Colorado and Utah meet. Since then, while these power plants have slashed their overall sulfur emissions by 72 percent, the canyon’s haze remains—evidence that the problem isn’t merely local.
Whether the Bush administration’s proposed air quality regulations will more effectively reduce pollution in the worst-hit parks is hotly debated. The present system “is tied up in the courts,” says Jim Connaughton of the White House Council on Environmental Quality. The Clear Skies Initiative aims to replace the strict limits governing an individual power plant’s emissions of sulfur dioxide and nitrogen oxides with a “cap-and-trade” system. Aplant that exceeds a limit for a pollutant would buy or trade credits from an operator that was under the limit for the same compound, keeping the nation’s overall pollution in check. Proponents, including many Republicans and most industry lobbies, say the plan is simpler, allows companies to be flexible, and lets some stay in business without buying expensive clean-up equipment. If a plant goes over its limit and has no credits to buy its way clear, EPA officials can levy fines with fewer hearings and lawsuits.
Connaughton also says that the proposal preserves longterm national goals on clean air and will improve visibility in the national parks. The proposal aims to reduce emissions of sulfur dioxide, a prime cause of haze and acid rain, by 73 percent by 2018—down 8 tons from the 11 million tons emitted in 2000. At the same time it would cut nitrogen oxides, a cause of ozone, by 67 percent.
But opponents see Clear Skies as a sellout to industry. They say the proposal is less aggressive than current regulations, and they complain that it would let dirty power plants operate as long as their owners buy credits elsewhere. Many environmental organizations have attacked the proposals. “Why is the Administration bragging about a plan that will actually result in more pollution than if we simply enforced the existing Clean Air Act?” the Sierra Club asks. In 2002, Eric Schaeffer quit his job as the EPA’s regulatory enforcement head, protesting what he says is the Bush administration’s soft approach to power company pollution. “If you allow them to buy their way out of reducing emissions, then the parks may not get better for a long time,” he says. Clear Skies opponents also say the plan would put park air at risk because the cap-and-trade credit system takes the teeth out of the parks’ Class I designation. Park superintendents would no longer have clear authority to demand that the EPA or other agencies go after individual polluters. The Clear Skies legislation is currently stalled in a Senate committee.
Bartering has worked in the past. Since 1990, power plants have been allowed to use a cap-and-trade system to help reduce acid rain, produced largely by coal-fired plants spewing nitrogen and sulfur. Consequently, sulfur emissions went from 17.3 million tons in 1980 to 10.6 million tons in 2003.
Park service expert Mark Scruggs is guardedly optimistic about the Clear Skies Initiative. “If the caps are stiff enough, sure, it will help a lot,” he says. “A 70 percent cut in sulfur dioxide is going to make a difference, especially for the East Coast parks.” But Scruggs says that when the current system is at its best—when agencies work together to prosecute individual polluters—results are impressive. EPA pressure on industry led to improvements in scrubber technologies, which reduce smokestack emissions, with 95 to 98 percent elimination of some pollutants now commonplace. Scruggs says similar improvements are possible for other pollutants.
But park lovers shouldn’t expect big improvements soon. The EPA’s deadline for returning park air to normal is 2064, a date instructive both in its temporal distance and legalistic precision. To be sure, there have been isolated gains. Sulfate haze tends to be dropping in the East, even as nitrate pollution and ozone are rising a bit in the West. In January, the park service said it met its 2004 performance goal of achieving stable or improving air quality in at least 62 percent of monitored parks, with 15 getting cleaner and 16 staying the same. Still, 18 got worse—including high-profile destinations such as Acadia, Death Valley, Grand Canyon and Yellowstone.