A tanker carrying ethanol fuel additive crashed on Interstate 70 the other day, and the road was closed near Vail for half a day. Not an unusual accident, but it happened just as the U.S. Army was thinking about breaking its promise not to haul dangerous chemical weapons across Colorado. The move would require congressional approval since the law does not allow these mustard gas shipments to cross state lines.

The move would also reverse the Army's existing plan to dispose of the aging munitions in a planned facility at the Pueblo Chemical Weapons depot. If a tanker crash can cause so much hassle, imagine the public outcry if the truck instead had been carrying mustard gas. Imagine the outcry if terrorists had grabbed the truck.

Since 1988, the Army's many studies have said it's impractical to transport the 2,600 tons of mustard gas at the Pueblo depot to other sites for destruction, because of costs and safety hazards. Indeed, just to destroy the munitions at the Pueblo depot, the Army must design special trucks and repave a road - and move the shells at a safe but glacial 2 miles per hour.

Alternative sites for destroying the weapons are in northwestern Utah, eastern Oregon, Arkansas and Alabama. But getting the mustard gas anywhere would require transporting the 780,000 shells hundreds of miles over public roads or rail lines. Some possible routes run through Colorado Springs and metro Denver.

Earlier this week, the Army promised Colorado Sens. Wayne Allard and Ken Salazar that the chemical weapons would be destroyed at Pueblo, as stated in the current, public plan. But just days before that, the Pentagon official in charge of the program ordered the Army to look at moving the mustard gas. The contradiction hasn't been explained.

Pentagon official Patrick Wakefield was supposed to send Allard and Salazar another memo explaining the contradiction by Friday. He missed the deadline.

Documents show the Army wants to shift money from Pueblo and a similar project in Kentucky to make up for cost overruns at other chemical weapons disposal facilities, which use incineration. Frankly, the Army has played games with Colorado for decades regarding chemical weapons disposal. Allard and Salazar are taking Wakefield at his word and expecting the mustard gas shells to be destroyed at Pueblo. They shouldn't be so trusting.