An environmental review that addresses how sediment will be managed during the proposed removal of Condit Dam on the White Salmon River is available for review from the Washington Department of Ecology (WDOE).
Comments will be accepted on the document until July 20.
PacifiCorp plans to begin removing the dam in October 2010, contingent on obtaining necessary regulatory approvals.
WDOE undertook this supplemental review to better understand the implications of releasing the sediments behind the dam during dam removal. Elevated levels of naturally occurring mercury were found in some of the sediments. Studies indicate, however, that the release of the material during dam removal would actually reduce risks from the mercury by making it less likely to accumulate in fish. Mercury is present in the environment from naturally occurring sources and from atmospheric deposition. It is not uncommon to find mercury in sediments behind dams.
Mercury can cause serious health problems for those who eat large amounts of contaminated fish. Exposure to the developing fetus and young children is of particular concern.
In addition to addressing the sediment issue, the draft second supplemental environmental impact statement for the Condit Dam removal project looks at a change in the proposed location for disposing of concrete during demolition of the dam. WDOE previously conducted an environmental review of the project that compared the effects of continued operation of the dam with dam removal. The environmental reviews are necessary for the agency to issue regulatory approvals associated with the project.
In particular, before the dam may be removed, PacifiCorp must obtain a Section 401 Water Quality Certification from WDOE. The 401 certification under the federal Clean Water Act would certify that water quality standards and other water-protection regulations are met during dam removal and subsequent restoration. The 401 would outline the steps PacifiCorp must take to protect water quality during dam removal.
The Draft Second Supplemental Environmental Impact Statement for the Condit Dam Removal Project can be viewed on-line at: www.ecy.wa.gov/programs/wr/cwp/condit.html
Address comments in writing to Derek Sandison, Department of Ecology, 303 S. Mission St., Suite 200, Wenatchee, Wash., 98801, or e-mail to: email@example.com