River cleanup is slow, expensive and maybe hopeless
Calabretta directs the biggest mining cleanup project in the Silver Valley - a three-mile stretch of Canyon Creek, which is one of the most polluted tributaries of the Coeur d'Alene River. Researchers have measured zinc levels here 200 times the federal standard for protecting aquatic life.
"It will be about 10 to 15 years before the wetlands begin to recover," " Calabretta says.
Last winter, Calabretta's crews removed 500,000 cubic yards of zinc- and lead-laced tailings here that stood 20 feet deep in places. Workers excavated until they came down to massive cedar stumps, remnants of an old swamp. The stumps signified the existence of organic soil. There is no aquatic life in the stream, and vegetation is scarce.
"Every now and then we'll see a bug of some type and get pretty excited about it," " says the former state senator as she wrestles the truck over bumps and through gullies.
Crews have built pools in the streambed to slow flooding and provide fish habitat. Wetlands on the flood plain have been seeded with metal-resistant grasses and mulched, while about 550 cedar stumps will be scattered to provide shade.
The contaminated soil, including an estimated 80,000 tons of lead and 1,500 tons of zinc, was trucked to a repository carved into a nearby hillside. An eight-foot layer of streambed cobblestones lines the bottom of the repository so groundwater can flow under and not through it. The tailings on top are compacted and capped so that water will not permeate it.
"It's like a brick sitting on top of a rock above the 100-year flood plain," " Calabretta says.
Estimated cost of the Canyon Creek project is $3 million, about $1 million per creek-mile. Most of the money comes from a 1986 settlement between the state of Idaho and several mining companies operating here. The state settled for $4.5 million after the Idaho state Legislature refused to fund a legal challenge.
Thus far, the trust fund is the only source of money for cleanup projects on the watershed outside the federal Superfund site.
Even with all the work, Calabretta isn't sure the project will restore fish habitat or stop more pollution from flushing downstream. She calls the project "a demonstration" that will provide valuable baseline data for future restoration projects, should money become available.
Tribal officials like much of Calabretta's stream and wetland restoration, but tribal biologist Phil Cernera says it may be a wasted effort.
"You've still got all that contamination coming out of the Burke Mine site (three miles above the project)," " he says. "That's going to continue coming downstream and contaminate this area again."
But Calabretta has no authority to force Hecla Mining Co. to clean up the Burke Mill, and the trust fund will be spent by the turn of the century. She says she has chosen cleanup sites based on the cooperation of landowners and the cost effectiveness of the projects.
It is a piecemeal approach, she admits, but at least some work is getting done.