This week the public will have another opportunity to comment on revisions to a Natural Resource

3B sediments and Tunnel Pond
Under the proposal, contaminated sediments would be removed from the old channel of the Clark Fork (middle left) and placed in the Tunnel Pond repository (right).



Damage Program grant that would fund the removal of an additional 250,000 cubic yards of contaminated sediment from the old Clark Fork River bed at the Milltown Superfund site.

On Thursday August 20 at 1:30 p.m. the Upper Clark Fork River Basin Trustee Restoration Council will consider the restoration grant amendment involving the removal of the contaminated sediments and disposal of those sediments within the onsite Tunnel Pond disposal area. For details,  see the agenda, background paper and map of the area .

Roughly 2.2 of 6.6 million cubic yards of contaminated sediment will be removed from the Milltown Reservoir. While the Environmental Protection Agency believes that it is removing the worst of the sediment - the material that contributed to the arsenic contamination in the Milltown aquifer - there remains another 250,000 cubic yards in the former Clark Fork channel that many believe should also be dug out.

Dubbed the "3B sediments," this relatively small amount of heavy-metal-laden mud has generated long negotiations between the State Natural Resource Damage (NRD) Program, Envirocon, and ARCO's insurer, AIG. This former river mud is just as contaminated as the reservoir sediment and unless the State NRD Program finds a way to remove it, it will sit as an unnatural looking armored repository at the otherwise-restored naturally functioning confluence.

In December 2007, Governor Brian Schweitzer approved a roughly $2.8 million NRDP grant proposal from the Clark Fork Coalition to remove and dispose an additional 560,000 cubic yards (cy) of contaminated sediment from the Milltown reservoir beyond the 2.2 million cy of contaminated sediment slated for removal as part of the Superfund remedial action. Subsequent negotiations among NRDP, the Atlantic Richfield Company (ARCO), AIG (ARCO's insurance carrier), and their contractor, Envirocon led to a modification of the 2007 proposal, reducing the cost and scope of the project. The amended proposal now calls for removal of 250,000 cy of sediment and depositing it in the on-site repository at Tunnel Pond instead of the BP-ARCO repository near Opportunity as originally proposed by the Clark Fork Coalition.

The revised project would cost an estimated $1.65 million dollars. One time-critical element of the proposal is that the agreement needs to be finalized by August 21, 2009 in order for the 3B sediments to be placed in the Tunnel Pond repository by Envirocon as part of its on-going remedial work, thus ensuring significant cost savings.

At the Thursday's meeting, NRDP staff will request that the trustees recommend for approval by the Governor the revised agreement.

The council meets in Room 152 of the State Capitol Building. For more information, contact Kathy Coleman at 444-0229.

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