Dames & Moore, 1999 - USDA Forest Service

INTRODUCTION
The olden Mine was operated between 1938 and 1957 by Howe Sound Company at a site located
approximately 12 miles west of the boat landing at Lucerne on Lake Chelan, situated in Chelan County,
Washington. The mine and mill facility processed ore removed from an underground mine on the site for
offsite smelting. Since closure of the mine, potential environmental concerns were identified by the
USDA-Forest Service (USFS).
The USFS attempted to address the concerns during site construction activities between 1989 and 1991.
However,, the agencies identified several potential concerns for further evaluation in a Remedial
Investigation (RI), the most significant being: (1) the presence of compounds of potential concern in surface
water, groundwater, and stream sediments in an adjacent stream (Railroad Creek); (2) the potential release
of tailings pile materials into Railroad Creek resulting hom erosion and p~ssible earthquake events; (3)
affects of the Site on aquatic biota and fisheries populations in Railroad Creek; and (4) wind-blown
.transport of, or direct exposure to compounds of potential concern in the tailings or other Site materials.
Alumet,.a successor to the Howe Sound Company, has since entered into an agreement with the USFS, US
Environmental Protection Agency (EPA), and the Washington State Department of Ecology (Ecology) to.
evaluate the potential environmental concerns.
The purpose of the RI is to:
Further characterize the environmental setting of the Site
Define the presence, magnitude, nature and extent of potential environmental concenls
determined to be associated with historic mining activities
Characterize potential pathways and rates of migration of compounds of potential concern
on the Site
Evaluate potential receptors of compounds of potential concern associated with the historic
mining at the Site
Characterize the stream habitat and the presence or absence of natural resource injuries
Evaluate the analytical data generated from the investigation in terms of applicable,
relevat, and appropriate regulations, including both state and federal requirements
Provide relevant data of sufficient quality so that the Feasibility Study (FS) can evaluate
cost-effective remedial alternatives to address significant environmental concerns identified
on the Site.
SITE DESCRZPTION AND BACKGROUND
The Holden Mine is situated on the eastern slopes of the Cascade Mountains in the Railroad Creek
watershed. The Site is situated at approximately 3,200 feet above sea level (ASL), with surrounding
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17693-005-019Uuly 28. l999;12:16 PM;DRAFT FINAL RI REPORT . ES- 1 DAMES & MOORE