Dames & Moore, 1999 - USDA Forest Service

which includes protected natural resources and wildlife habitat (Figures 8.1-1 and 8.1-2). The Site is
situated approximately near the center of the Railroad Creek watershed.
The elevation difference between the mouth of Railroad Creek and the westernmost exqent of the watershed,
as well as the difference between the floor of the valley at the Site and surrounding peaks, is on the order of
4,000 to 6,000 feet. This elevation difference results in wide variations in daily and seasonal temperatures,
and the types and amounts of precipitation. The majority of precipitation falls in the form of snow during
the months of January through March. Daytime temperatures at the Site are relatively cold during the
winter months, often below 32 degrees Fahrenheit, to warm during the summer months, often above 70
degrees Fahrenheit.
The daily temperature variations in the summer months regularly result in down-valley winds during the
afternoons, which are normally low to moderate in relative intensity. The north-facing aspect of the Site
also reduces the amount of solar gain received during the year when compared to the north side of the valley
which receives more sunlight. These factors contribute to the variations in snow melt rates; surface water
run on, runoff and infiltration; and the species and densities of vegetation and wildlife. The vegetation types
range from lower elevation,.predominantly coniferous forests from Lake Chelan to the Site, transitioning to
subalpine and alpine sparse vegetation west of the Site to the headwaters at Lyman Lake.
The principal Site surface features in the southwest and western portions of the Site include the underground
mine, the Honeymoon Heights area portals and associated waste rock piles, the 1500-level main and
ventilator mine portals, the mill building with two associated waste rock piles and mine support area which
includes the maintenance yard, lagoon (Figures 8.1-3 and 8.1-4). Three tailings piles are present in the
eastern portion of the Site and cover approximately 90 acres. The tailings piles range in height from
approximately 50 feet for tailings pile I, approximately 120 feet for tailings pile 2, and approximately 50
feet for tailings pile 3. Railroad Creek bounds the mine area to the north. Copper Creek enters Railroad
Creek between tailings piles 1 and 2.
Holden Village exists north of the abandoned mine and mill areas, immediately north of Railroad Creek.
The village includes'approximately 50 to 60 year-around residents and approximately 5,000 to 6,000 short-
term visitors to Holden Village during the summer months. Other short-term visitors to the Railroad Creek
watershed include hikers, backpackers, horse packers, and recreational users who fish the streams and 'lakes
throughout the area. Lucerne, approximately 10 miles to the east of the Site, near the mouth of Railroad
Creek on Lake Chelan, includes mostly part-time and several full-time residents.
Aquatic Reference Reaches
The three aquatic reference reach sites were selected for evaluation in the RI and are located to the north of
the Railroad Creek watershed within the Stehekin River basin (Figure 8.1-5). The sites are situated on
isolated segments of Bridge Creek, North Fork of Agnes Creek, and Company Creek. These reference
reach sites were selected because they are situated in areas of similar topographic relief and climatic
conditions as observed in the Railroad Creek watershed. The reference reaches are also situated in remote
areas of the Wenatchee National Forest or the North Cascades National Park, with only part-time visitors in
the form of hikers, backpackers, horse packers, and recreational users who fish the streams and lakes.
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