Once-Pristine Big Bend National Park Now Plagued by Air Pollution

For years, Nancy Sykes’ outdoorsy husband had been trying to drag her to Big Bend, which he described as “the most beautiful place on Earth.”

But once she finally got here, what she saw--or didn’t see--sent her packing two days early.

Unlike when James Sykes first visited this remote, southwest Texas treasure in 1975, today white haze hangs over the park, obscuring if not completely blocking scenic landscapes in the distance.

“Isn’t it awful?” bemoans Nancy Sykes, 44, who drove about 10 hours with her husband from their hometown of League City, near Houston. “Every time I look at it, it makes me angry.”

“It’s really disappointing,” adds James Sykes, 51, “if you know what the view was before the haze.”

The Sykeses are hardly the first to complain about the smog, which began creeping into the 800,000-acre park more than 20 years ago. Big Bend, one of the most popular Texas destinations for outdoor enthusiasts with its rugged mountains and raft trips along the Rio Grande, is now considered one of the most polluted national parks in the West.

The once-pristine site--300 miles from El Paso, the nearest major city, and so remote that not a single FM radio station comes in clearly--today is as smoggy as some urban areas.

The concerns of park visitors and area residents prompted a 1996 preliminary study, which found that power plants in both Texas and Mexico were contributing to the milky haze. Before the study was commissioned, U.S. officials long held that twin coal-burning power plants 125 miles southeast in Mexico were the principal cause of the pollution.

Now the Environmental Protection Agency and the National Park Service have undertaken a more extensive, $6.3-million study to determine exactly what is in the air and how it got there.

Officials hope to use the information eventually to limit the pollution drifting into the park.

“If we know for sure Texas is a major contributor, we could go to those sources and implement technology to reduce the amount of pollutants,” says Vidal Davila Jr., the park’s acting superintendent.

But while Mexico participated in the 1996 study, it declined to be part of the new one, which began in July and ended Oct. 31.

Alfredo David Gidi of Mexico’s environmental protection agency said Mexican officials wanted to participate in a second study but believed the one proposed to them was poorly designed and likely to reflect only problems south of the border.

U.S. officials proceeded by releasing chemicals--so-called tracers--from a tower in the Texas town of Eagle Pass, just across the border from the twin coal-burning plants near Piedras Negras, Mexico. The idea is that by releasing the harmless tracers, scientists were simulating emissions from the twin plants on the other side.

Then, over at Big Bend, scientists sampled the air to see if the tracers drift over.

Chemical tracers also were released in northeast Texas, San Antonio and the Houston area. Air samples were collected at a total of 38 spots in Texas and Oklahoma, so that scientists can map out where chemicals are released and where they end up.

At an outdoor laboratory set up at Big Bend, sophisticated devices that resemble the kind of electrical-switch boxes found in an average home sucked in air through metal tubes. Filters were sent away for analysis.

From this spot in the middle of the Chihuahuan desert, the mountain ranges in the distance appear to be gray--those closest, a dark gray, those farther away, a lighter shade.

“You should see individual bushes on these mountains,” said National Park Service technician John Forsythe, noting they are only 15 to 18 miles away.

On good days, visitors are lucky to be able to see 100 miles away, but the maximum visibility at the park--without the haze--is 243 miles.

Forsythe and researchers from Colorado State University and the University of California-Davis worked at the outdoor lab, monitoring equipment and running experiments.

It’s currently believed that the following sources are at least partly responsible for the pollution: the Piedras Negras plants, petrochemical plants along the Texas Gulf Coast, coal-burning plants in northeast Texas and elsewhere, and industrial areas of northern Mexico such as Monterrey.

What is clouding the view is tiny dust particles containing sulfur or carbon. The particles, which can be blown to Big Bend from several hundred miles away, have previously been linked not only to power plants and oil refineries but to diesel fuel and wildfires.

Windblown soil and humidity also limit visibility.

“One feels almost desperate some days when the air is so awful out here,” says Fran Sage, who formed a local branch of the Sierra Club three years ago because of the haze.

She hopes the new study will spark a dialogue between the Clinton administration and top Mexican officials on ways to limit the smog.

Miguel Flores, coordinator of the study for the National Park Service, aims to have preliminary results to the EPA by next summer. He said the findings will help the park service develop a strategy for reducing the haze.