The Site contains areas affected by mining, including three principal areas that were directly affected by mining along with other areas, primarily downstream, where hazardous substances have come to be located. The three principal areas include the 1950s Mine and Mill Area, the 19th Century Operations Area and a Main Tailings Impoundment. The Action memo recommends response actions to address threats from the main tailings impoundment.
The 1950's Mine and Mill Area comprises 15 acres and is located northwest of the intersection of Ore Knob Road and Little Peak Creek Road, just north of Highway 88. This area contains derelict ore bins, concrete mill foundations, a transformer building, other ruins, a small sawmill currently in operation, two acres with about 10,000 cubic yards of tailings - now mostly covered with stumps, and a two acre former pond where process water was stored. Little Peak Creek starts just upstream of the former pond, flows through the former pond, and discharges into Peak Creek 2.5 miles downstream.
The 19th Century Operations Area and the Main Tailings Impoundment are located across Little Peak Creek Road, at the end of Ore Knob Mine Road. The 19th Century Operations Area includes a series of barren and nearly barren stretches of land (totaling about 5 acres) near the top of Ore Knob that contain waste rock dumps from at least 11 mine shafts as well as locations where ore was roasted to drive off sulfur and smelted to recover copper.
Mobilization to the site occurred on 4/26/2009 and site activities resumed on 4/27/2009.
During this reporting period, activities conducted at the Site included: monitoring of ground water quality at the designated monitoring locations, excavation of subsoil from the eastern hillside at locations 4+00 to 6+00 and relocating to stockpile area, backfill of pond #3, clearing of trees and brush from the southern hillside south of pond #3, excavation of the southern hillside to create a haul road, excavation at the toe of the starter dam placement of large rock to create the first shear key, excavation of loose rock, removal and stockpiling of materials from the location of the proposed diversion channel.
During the next reporting period, activities conducted at the Site will included: monitoring of ground water quality at the designated monitoring locations, guaging water level measurements behind the dam from northernmost line of monitoring wells, excavation of subsoil from the southern hillside at locations 0+00 to -5+00 and hauling to stockpile area, clearing of trees and brush from the southern hillside south of pond #3 at sections -2+00 to -7+00, excavation at the toe of the starter dam and placement of rock to stabilize the starter dam creating the first shear key, excavation of loose rock, removal and stockpiling of materials from the location of the proposed diversion channel.
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