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section of the plant will be pulled from the milling circuit for collection and further treatment. The overflow from the shaking table will carry the suspended, finely divided frac- tion of the pulverized ore to a large thickener tank. This thickener tank will serve two important functions. It will clarify the mill water, which will be returned to the ball mill for recycling in the gravity circuit, and it will in- crease the concentration of the suspended solids prior to their flotation. The clarified water will overflow a periph- eral launder, while the solids will settle on the bottom of the tank. Four rotating radial arms with blades will rake the settled solids towards an outlet at the center of the bottom of the tank. These rotating blades will also assist in the compaction of the settled particles, produce a thicker under- flow, and promote faster clarification of the mill water. A diaphragm pump will be used to lift the thickened pulp to a bank of flotation cells, where the concentration process will be completed. Standard flotation reagents such as pine oil, soda ash, and xanthate will be used in the flotation cells. The tail.' role the flotation circuit will be pumped to the tailirSy'~`~"~{'~"- d the final concentrate pulp will be collected for filtration. A disc vacuum filter will dewater the flotation concentrate, which will be shipped from the millsite for further treatment. The Gold Hill Ventures' mill has been designed to have the capability to process 50 tons of ore in a 24 hour period. Because the crushing plant section of the mill will be able to crush enough ore in a single 8-hour shift to furnish the grinding circuit of the mill with a 24-hour supply of fine ore, it will only be operated one shift a day. In order to achieve efficient grinding, maintain the ratio of concentra- tion, and insure a high level of recovery, the grinding and concentrating circuits will be operated continuously. Initial- ly, the milling facility will be operated 3 or 4 days a week for 24 hours a day. This schedule is based upon producing 20 tons of ore a day from the Cash mine, and sorting 20 tons of mine dump material a day for 5 days a week. Later, after full scale production has been attained from both underground mining and mine dump sorting operations, the mill will be operated 5 or 6 days a week for 24 hours a day. A six-man mill crew will be employed in the milling facility. Tailings Impoundment Area Several areas on Horsfal Flat near the proposed millsite were evaluated for tailings disposal. Consideration has been given to locating an area with an adequate storage capacity, and with suitable topographic, geologic, and hydrologic character- istics for the construction of a safe disposal area that will be compatible with the surrounding environment. Prior to selecting a final site, all of the patented and unpatented mining claims in this area were re-surveyed, their monuments re-established in the field, and their boundaries plotted on an accurate claim map. A detailed (1 inch = 50 feet) topo- graphic map with 5 foot contour intervals was completed using a plane table and alidade. Both of these maps were then used in conjunction with the detailed geologic map of this area, to insure that the ownership, topographic, and geologic condi- tions were mutually advantageous for tailings disposal. Finally, a field examination of the several areas most suit- able for use as a tailings pond focused on the availability of borrow material suitable for dam construction, access, and security. The area northeast of the proposed millsite has been selected for the construction of an impoundment dam to contain the tailings that will be produced by the milling process (see Maps B2 and E2). The site selected for the location of the tailings pond is on property owned by the Gold Hill Ventures ..,Limited Partnership. An adequate storage capacity can be -10-