By Mindy Sink
New York Times
DENVER – Interstate 70 in the Rockies can be at its busiest in winter, when hordes of skiers from around the world join the daily tide of commuters and long-haul truckers climbing the Continental Divide. All of them expect the road to be free of ice. And that is creating an environmental problem that lasts far beyond winter.

The problem lies in the tons of sand, salt and liquid chemicals that highway workers use each winter. In particular, sand laced with chemicals and salt has accumulated on roadsides for decades, taking a growing toll on the rivers and vegetation in this fragile environment.

The Colorado Department of Transportation estimates that $35 million will be needed to clean up the sand and install a proper drainage system.

"This is not a safety-versus-the-environment issue," Representative Mark Udall, Democrat of Colorado, wrote to Robert Roberts, regional director of the federal Environmental Protection Agency. "We ought to have both. We need to make sure that these water sources are being protected while at the same time make sure that Interstate 70 is safe to motorists during the treacherous winter months."

Mr. Udall also wants to know whether the use of sand complies with the Clean Water Act. It is widely believed to be affecting water quality, choking streams and vegetation. Studies are also under way to determine whether magnesium chloride sprayed on slippery roads is causing power failures and vehicle corrosion.

Colorado is not the only state with such problems. Sens. John W. Warner of Virginia and Lincoln Chafee of Rhode Island, both Republicans, have added a provision to the transportation bill now before Congress to set aside federal funds to help the states with road cleanups.

A five-year study in Canada has found that road salt, a toxic substance, can damage waterways, soil, vegetation, fish, birds and some wildlife without harming people.

In Colorado, a regional director of the Transportation Department, Ed Fink, said any technique to remove ice and snow would affect the environment. "There are a lot of tradeoffs and no pat answers," he said.

He is working with the National Cooperative Highway Research Program, an arm of the National Academy of Sciences, on a booklet that will outline the pros and cons of different methods in diverse climates.

A spectrum of interests, including the trucking and tourism industries and water utilities, are concerned about solutions. Some environmentalists are examining the effects on ecosystems and wildlife, as the Transportation Department tries to balance among the interests and lower accident rates.

"Everybody is split," said Reeves Brown, president of Club 20, a coalition of 22 counties along the Western Slope of the Rockies. The group met in December and is to meet again in the spring, to discuss the effects of magnesium chloride in particular.

Studies show that accident rates have recently declined because of improved snow and ice removal.

"The pressure is tremendous," said a spokeswoman for the Transportation Department, Stacey Stegman. "When we have a storm with any amount of ice that our crews aren't at their best with, we are bombarded with complaints. There is an expectation that people in Colorado will be able to drive on wet roads in the worst of conditions."

Caroline Bradford, executive director of the Eagle River Watershed Council in Minturn, Colo., said: "The Colorado Department of Transportation's mission is to provide a safe roadway, and our mission is to advocate for the health of the watershed. Oddly enough, those two things appear to be at odds."

Ms. Bradford said she understood the department's need to keep the roads safe for driving. "But we want them to do it in such a way that they don't degrade the habitat," she added. "It's possible. It just costs money."

In the last two years, Ms. Bradford said, 48 sediment basins have been built, at a total cost of $1.5 million, to catch sand along Interstate 70 as it sweeps down the mountainsides.

But "preventing traction sand" from reaching waterways is difficult, said Mr. Roberts, of the E.P.A., who added, "Restoration will be even more technically problematic and expensive."

In another letter to Mr. Udall, the executive director of the Colorado Transportation Department, Thomas E. Norton, said the $35 million would be needed to carry out his agency's sediment control plan. But he acknowledged that "the program was largely unfunded."

The plan would involve overhauling the highway drainage along Straight Creek and Black Gore Creek, two 10-mile-long segments 75 miles west of Denver.

In the Denver metropolitan region, sand has is rarely been used since officials learned in the late 1980's that the particles contributed significantly to the infamous "brown cloud" that hovers over the city.

The alternative has been magnesium chloride or similar liquids applied in anticipation of freezing conditions. Now, some authorities fear, the components that make the roadway sticky are gumming up electric lines and causing power failures.

"It should be said we do support the use of magnesium chloride and the larger issue that addresses with safer roads and clear skies," said Steve Roalstad, a spokesman for the local power company, Xcel Energy. "That said, we do know that magnesium chloride is a contributing factor to some outages."

The utility says the magnesium chloride and sand mix with the snow and form a vapor that ends up on poles, substations and other sensitive electrical equipment, where it can result in fires and short-circuits.

The department has tested the effects of magnesium chloride and says it found the salt to be cost- effective and friendly to the environment.

"The problem we face is that there isn't a perfect product out there for de-icing the roads," Ms. Stegman said. "There is a negative tradeoff to any product on the market. What we do is try to find something where the benefits outweigh the negative impact."