As Kouri sees it, tarping is an impractical solution anyway. He argues that the owners of the salt piles--which include the giant, Minnesota-based multinational Cargill, Inc.--ought to build enclosed storage facilities for the salt. That's what the Minnesota Department of Transportation has been doing since concerns about runoff from road-salt piles first surfaced in the 1970s, according to Norm Ashfeld, metro maintenance superintendent with MNDoT. "All our salt piles are in a shed on a nonpermeable pad," Ashfeld says. "We take great pains to keep our salt as environmentally friendly as possible."
That said, MNDoT purchases its salt from bulk sellers like Cargill that don't adhere to such practices. As for Cargill, company spokesman Allen Holbert says compliance with environmental regulations is the responsibility of River Services, Inc., the company that manages the Upper Terminal for MCDA. River Services, Inc. manager Jerry Christianson is currently on vacation and could not be reached for comment.
But the storage of salt is almost beside the point, say environmentalists like Simon. After all, even the best facilities can't keep the salt out of the rivers and lakes once it's been applied to the roads. Considering the damage salt inflicts on nonaquatic plant life like roadside pine trees and grasses, critics argue that earth-friendly de-icers ought to be used. "There's better alternatives," Simon says, "stuff made from things like soy and brewery byproducts."
According to Ashfeld, MNDoT has experimented with corn-based de-icers, and has taken to applying a "salt brine" to dry roads in an effort to reduce the amount of additional salt needed once bad weather hits. But Ashfeld says cost remains an obstacle in the search for alternatives. "We pay about 24, 25 dollars a ton for salt," Ashfeld says. "Other products cost 800 to 1,200 dollars a ton and they don't melt as effectively. So, in effect, for every ton of salt, you'd have to use two tons of the other stuff, and there's no way our budget could handle that." According to Ashfeld, MNDoT currently goes through between 75,000 and 100,000 tons of road salt yearly in the eight-county metro area.
Despite the findings of illegal levels of discharge at the River Terminal, nobody has yet demonstrated a direct correlation between the cyanide and any die-off of aquatic life. But that, Simon argues, is probably due to a lack of aggressive investigation. Besides, he points out, the use of road salt has other hidden costs, in the form of corrosion of vehicles, bridges, and road surfaces--costs that ought to play into policymakers' calculus as they weigh different options. Because of the findings of illegal runoff from the salt piles, Simon adds, Mississippi River Revival is now contemplating filing suit against various municipalities and corporations under the federal Clean Water Act.
Meanwhile, Cherryholmes says the MPCA will probably look to develop a statewide regulatory process to better govern the storage of road salt. He points out that the Upper Terminal is hardly the only site where runoff has been a problem. Tests on at least three other storage facilities in the state, including the Dakota Bulk Terminal in South St. Paul, revealed excessive levels of both chloride and cyanide, according to Cherryholmes. He says he expects that notices of violation will be issued in those cases as well.
"For years, we've had complaints about the road salt, but I don't think anybody ever considered banning it. I think there's a reluctance to change these practices because salt is economical," Cherryholmes says. "And for years, nobody but the salt people knew there was cyanide in there. The more the public understands the ramifications of this, the better off we'd be," he adds, concluding, "I think most people know that cyanide is a very toxic material, and that we need to be extremely careful."