Dames & Moore, 1999 - USDA Forest Service

4.1.2 Site Surface Features
Referring to Figures 4.1-3 and 4.1-3a and Table 4.1 - 1, the Site has been divided into defined areas, based on
past and present uses, for discussion purposes.
4.1.2.1 Mill Building, Mine Support Area, and Waste Rock Piles
The mill building is located near the center of the Site on two patented mining claims (Lucille Millsite and
Copper Creek Millsite) deeded to Holden Village, Inc. ~efeiin~ to Figure 4.1-4, the mill building was '
constructed in a stair-step fashion down the slope from the 1500-level mine portal level (near the "Main
office, warehouse, machine shop, compressor room" noted on the figure) to the valley bottom,
approximately 200 feet below the portal elevation. The stair-step design allowed gravity to move the ore
through the processing from the "ore storage bin," through the milling process, and to the "loading bay" as
concentrate.
The method of metal extraction was a froth flotation treatment of the ore (McWilliams, 1958). The ore rock
was mixed with water and further crushed to pass through a 200-mesh screen. The resulting mud was
treated with pine oil reagents to coat the metallic minerals with a water repellent film. The sluny was then
agitated in tanks while air bubbles were added to pull the water-repellent complexes with them. This
process was repeated to separate the minerals. Recovery of copper and gold was reported in 1939 to be 94
and 81 to 83 percent, respectively (Pearse and Zanadvoroff). The extracted minerals were then transferred
to trucks for transport to Lucerne, where the concentrate was transferred to a barge for transport to the Town
of Chelan and then by rail to the City of Tacoma, Washington, approximately 175 miles west, for smelting
(Huttl, 1937).
Some of the components associated with the historic crushing and grinding of the ore, as well as portions of
concentration tanks, are still present. The mill building currently consists of concrete foundation walls and
the remnants of the original metal structure and walls. A portion of the structure and the majority of
equipment was apparently removed during the salvage operations (communications with Keith Anderson,
formerly of the USFS, 1996). Water seepage was observed during the spring months throughout portions of
the facility during the RI; the water appeared to originate from the southern foundation walls and flowed
generally north to the northwest corner of the building before exiting to a ston drain and eventually into the
lagoon feature northwest of the facility.
Due to safety considerations, the mill building was not entered during the RI. However, the perimeter of the
building was assessed. An estimated 10 cubic yards of unprocessed ore was observed in the uppermost
portion of the mill, in the area noted on Figure 4.1-4 as the "ore storage bin." Remnants of apparent
insulation were observed in the exposed walls of the building; the material appears to be a wood product.
The roof of the mill building was removed during the salvage operations and the area is, therefore,
uncovered. Indications of mineral salts were observed on the surfaces of the ore material and remnant
concentrate tanks, and mill foundation. A set of inclined tracks was observed along the western portion of
the building, likely associated with an inclined tramway. Water was noted flowing from the uppenost
portion of the building and down the tracks during the spring months. The source of the water appeared to
be the cut slope to the south of the building.
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17693-005-0 I9Uuly 19, 1999:4:51 PM:DRAFT FINAL RI REPORT