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3.9.1 Mill Water Treatment Facility Construction -DMG #25b During the planning stages for the Woods Creek water treatment plant, Henderson reviewed cost estimates for several systems, including a 2-stage system similar to that planned for the Argo site. It was during this planning process that Henderson also began investigations into water treatment needs at the mill. The Argo facility is a 800 gpm unit using 2-stage treatment and a sludge press system. The "as-built" capital cost was $5,000,000 (pers. comm. -Ron Abel, CDPHE), the same number used by DMG in Task 25b. Presently, Henderson is proposing a 900 gpm facility (based on actual seepwater flows) but with single stage treatment and no sludge press capabilities. The capital savings is approximately $1,500,000, or $3,500,000 capital cost. However, Henderson is proposing to scale up this figure to $4,000,000, a reduction of $1,000,000 in the total FW for this line item. 3.9.2 Mill Water Treatment Operating Costs -DMG #25c MiII water treatment operating costs and mine water treatment operating costs are expected to be similar. TR-12 discussed Henderson's request to change the unit treatment costs based upon actual operating experience and records for the Woods Creek facility over the period 1999 - 2001. Exhibit E in TR-12 is incorporated by reference into this section. Henderson has operated the Wood Creek water treatment facility for five complete years. During this period, actual operating records have been developed to more accurately reflect the cost of treatment. Based upon these operating numbers and five years of experience at the water treatment facility, Henderson has calculated an accurate annual cost of $440 per gpm, less than half of the $953.50 per gpm per year estimate used by DMG in calculating water treatment costs. TR-12 (Section 3.6) discussed and requested a reduction in closure/reclamation time to three years for all elements. DMG Task 25c utilizes a 9 year treatment period for mill water treatment operating costs. This period should be reduced to six years. Using the $440 per gpm actual unit cost over a six year period fora 900 gpm facility, the estimated cost for Task 25c would change from $8,581,500 to 12