2004-08-11_REVISION - M2000156 (2)

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Coulson Excavating Company, Inc. -Bonser Gravel Pit RECEIVED Exhibit D -Mining Plan AUG 1 1 2004 Background and Procedure Divisinn~fMincralsandGeaingy Dry mining is the proposed method of mining, and therefore the primary extraction equipment will consist of backhoes and scrapers. Aggregate will be processed onsite through the use of aggregate processing facilities including a crusher and screening facility, a scale house, an asphalt batch plant, and associated aggregate and fines stockpiles. Mining Operations and Timetable The Bonser gravel pit is expected to be operational for approximately 10 years. The mine plan is divided into two 39-acre phases. Phase I is the east pit and Phase II is the west pit (see Figure 1, Exhibit D). Each Phase has been subdivided into mining cells Mining cells are approximate and the operation may vary from the cell boundaries. The mining operation will reclaim cells concurrently with mining. The sequence of mining for each Phase will follow the sequence of letter designation for each cell. The operation will mine Phase I, reclaim it and move on to Phase II, and as such each phase is to be separately bonded. It is anticipated that the mining operation will disturb approximately 8 acres within a particular Phase each year. Extraction is therefore, expected to last 5 years for each phase. Approximately 428,000 cubic yards (cy) of overburden will be removed during Phase I, and approximately 321,000 cy of overburden will be removed during Phase II (see Table 1). Table 1 Phase Overburden to be Removed Acres to be Disturbed Duration I -428,000 cy -8 acres per year --5 years II -321,000 cy -8 acres per year --5 years TOTAL -749,000 cy -78 acres total -10 years Water Diversions and Impoundments Trenches witl be excavated at the toe of each pit wall to expose groundwater, which will be pumped to a sediment pond {existing) located at the southwest comer of the permit area (see Figure 1, Exhibit D). The existing irrigation system is owned by Coulson Excavating Company, Inc. and consists of surface irrigation pipe for sprinkler irrigation. The piping will be disassembled prior to mining and will not be re-installed after mining is complete. Nature of the Overburden, Gravel Deposit, and Underlying Stratum Overburden within Phase I and Phase II consists of fine sand and silt. Topsoil in the area occurs at a thickness of less than 1 ft and consists of Table Mountain Loam, Table