Grand Concern for Grand Canyon

Environmentalists and scientists say a proposed cement plant may add a milky haze to the Grand Canyon's priceless views

A hiker’s first trip to the Grand Canyon is always awe-inspiring. The postcard views are world class. Red-stained buttes cut up the long skyline. Sinuous canyons, tattooed by wind and water, disappear into timeless depths.

Those views could all change by 2013 if a proposed cement plant in Seligman, AZ is approved, the Arizona Republic reported earlier this month. The proposed plant would be built less than 50 miles from the Grand Canyon and opponents say the region’s prevailing winds would likely blow a haze of toxic pollutants over the national park.

“There is just no reason to locate this type of highly polluting industry so close to the Grand Canyon,” Stacey Hamburg of the Sierra Club told the Arizona Republic.

“This thing is 40 miles south of the Grand Canyon. And the prevailing winds are out of the southwest. So whatever it puts out is going to end up at the Grand Canyon,” Roger Clark of the Grand Canyon Trust told Backpacker.com.

“Since the winds are not all that strong, and precipitation is not frequent, the haze from smokestack industries hangs in the air over the canyon and the entire Colorado Plateau north of Flagstaff,” Arizona State Climatologist Nancy Selover told Backpacker.com.

That means the pollutants will float over the South Rim of the canyon, where most of the park’s 4.4 million visitors flock every year.


Some worry poorer air quality may also cause extra respiratory problems for hikers tackling the lung-busting 5,000-foot climb from the canyon floor to the rim.

According to the article, the cement plant will heat limestone at temperatures up to 2,700 degrees Fahrenheit, producing various pollutants like nitrogen oxide, sulfur dioxide, and  particulates. Environmentalists also say Cemex, the company building the plant, has a history with the Environmental Protection Agency, including a recent $2 million settlement for smog-causing pollution in California.

The exact impact remains unclear until further studies are done but early guess-estimates show the cement plan would release 10% of the nitrogen oxide that the now-defunct Mojave Power Plant once released. The difference is the coal power plant was more than twice the distance from the park (about 100 miles).

The Arizona Department of Environmental Quality is monitoring air currents around the site. Clark says the permitting phase could take two more years, and so although it’s not imminent, it’s something to watch.

The Clean Air Act gives national parks Class 1 status, the highest protection for air quality in the United States. Since pollution already affects the park, it could mean the plan will not get the green light, Clark added.

The cement plant is one of several impeding threats for the park, including uranium mines, coal power plants, and car emissions from park visitors.

The best thing to do, Clark says, is to keep visiting Grand Canyon and to watch for a public comment process on the plant.

Our May 2009 issue highlights four hikes in Grand Canyon National Park. The issue hits newsstands in mid-April. 

-Sarah Curry

At Canyon, New Fears of Air Pollution (Arizona Republic)