The Idaho Department of Environmental Quality released Friday the conditions local businessman Duane Hagadone must meet to ensure that heavy metals aren’t released in Lake Coeur d’Alene and the Spokane River if he gets permission to dredge the Blackwell Island channel.
The public has until Aug. 15 to comment on the draft that outlines the types of dredging that would be allowed, how often workers should test water quality during the excavation and precautions to protect ground water and the aquifer.
“We’ve been working weekly with (Hagadone Corp.), and we certainly like this better than their original proposal,” said June Bergquist, a DEQ water quality compliance officer in the Coeur d’Alene office.
Yet environmental groups aren’t so comfortable with their first review of the draft that came out Friday afternoon.
“It’s kinda disappointing,” said Barry Rosenberg of Kootenai Environmental Alliance, who has concerns about the possibility of flooding stirring up contaminated soils that will be used to build up the elevation of the man-made island.
Hagadone officials didn’t return phone calls Friday, but in an interview earlier in the week engineer Jim Coleman said the company voluntarily changed the dredging proposal so most of the soils and silt would be removed from the channel when it’s dry. That means there is less chance of releasing heavy metals into the water, Coleman said.
Workers would use dams to keep out the water. Some of the work would be done in the water, but crews would use silt fences to keep the potentially contaminated soils from escaping.
Marina Yacht Club LLC, owned by Hagadone, wants to dredge the channel on the west side of the island to allow for larger boats. The dredging would make the channel at the mouth of the Spokane River about 50 percent wider and at least eight feet deep. The expansion would allow for about 530 boat slips, 29 more than are at the marina on the man-made island bisected by U.S. Highway 95.
On Tuesday, the Idaho Department of Lands denied Hagadone’s request to dredge the Blackwell Island channel because of insufficient details about the project’s impact on water quality and fish habitat.
Department officials said that they needed the information in DEQ’s draft water quality analysis but by law had to make a decision within 30 days of its June 9 public hearing.
Once DEQ finalizes the water quality certification, Hagadone officials will ask the lands department to reconsider its ruling.
The company also needs approval from the U.S. Army Corps of Engineers.
The excavated sand, silt and gravel – up to 220,500 cubic yards – would be used to fill in the east side of Blackwell Island, which was once a city landfill.
Workers would then cap the area with clean sand and gravel. Hagadone eventually plans to turn the area into a business park with condominiums, offices and shops.
The draft outlines plans to monitor this fill area for a year to ensure that heavy metals aren’t contaminating groundwater.
Hagadone also is asking Coeur d’Alene to include Blackwell Island in its city limits. The city council will have a public hearing on the proposal Tuesday. The 6 p.m. meeting will be at City Hall, 710 E. Mullan Ave.