Visitors to the Cataldo Mission along Interstate 90 in Idaho won’t see a hazardous waste storage site now that government officials plan to build a shorter mound of contaminated soil.
The 19-acre repository will top out at 34 feet. The original 62-foot design might have been visible from the neighboring Old Mission State Park in the fall, when trees are bare of leaves.
The mission is the most-visited heritage park in Idaho, and it’s the state’s oldest building.
“It’s in response to comments and concerns about the repository being a visual problem from the mission,” said Rob Hanson, the Idaho Department of Environmental Quality’s mine-waste program manager.
Some critics still question the placement of the East Mission Flats Repository – a stockpile of lead-tainted soil and other mine waste capped with clean soil, plants and trees – so close to wetlands and the flood-prone Coeur d’Alene River. They argue more studies are needed to determine whether the mining waste, much of which will come from residents’ yards and businesses, could harm the environment.
The height reduction will allow the state to stockpile 446,000 cubic yards of waste – a reduction of 202,000 cubic yards – at the site just north of I-90 and across from the mission. A regular pickup truck holds about 1 cubic yard.
The smaller design, approved by both the DEQ and the U.S. Environmental Protection Agency, means officials might need to build an additional repository for heavy-metals-contaminated dirt from the Silver Valley within a decade.
The repository is part of the EPA’s plan to clean up the basin and protect people from hazardous waste left from decades of Silver Valley mining.
For each of the first few years, it’s anticipated that residents and businesses will dump about 2,000 to 5,000 cubic yards of dirt at the site.
A new Idaho law requires the state to provide a place for residents within the Coeur d’Alene Basin to dump contaminated soil from their yards and businesses in the western edge of the contaminated zone.
Meanwhile, the state will complete the final design plans for the repository.
Rick Eichstaedt , an attorney with the Spokane-based Center For Justice, said the change resolves one concern but doesn’t address potential effects on wetlands, wildlife and cultural resources.
Eichstaedt represents the Sierra Club, which in July sent a letter to the state demanding a construction halt at least until after the public comment period deadline passed later in the month.
“You don’t start building the house before you have the blueprints,” Eichstaedt said Wednesday. “That’s essentially what’s happening here. There are fundamental environmental concerns as well.”
The Kootenai Environmental Alliance and the East Side Highway District also raised concerns, and about 500 residents signed petitions opposing the repository.
The DEQ and the EPA have studied the property. They say the repository is designed to avoid nearby wetlands, which are already contaminated by mining waste. Officials say the river is far from the site and the repository is designed to withstand floods and erosion.
Because the area is already contaminated, capping it with clean soil and vegetation will actually help clean up the area, officials say.
The DEQ’s Hanson said the state wants the dump site open by spring. Crews over the summer cleared the property and covered it with clean dirt. Monitoring wells were drilled to record the natural condition of the water in the area so when the mining waste arrives the state can tell whether it is leeching into the water.