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otherwise, overburden will be placed in stockpiles and stabilized against wind and <br />water erosion, or used to define water erosion controls. <br />Sequence of mining: See Map C-4. Up to this point, mining has been done in Areas <br />to 12. In general, mining from 2010 on will proceed from South to North. <br />Non-mining activities (related to mining) - to be conducted in accordance with <br />county and other permits/approval, as necessary: <br />1. Processing: screening, crushing, washing of sand and gravel <br />2. Hot-mix asphalt facility <br />3. Vehicle and equipment storage <br />4. Fuel and lubricants storage <br />Within each area, mining will be done working in from the downhill edge, to <br />prevent uncontrolled runoff. <br />Summary of surface water management (water and drainage features and <br />activities): Please see Exhibit G. Surface water management will comply with <br />state/county standards, permits, and good conservation/engineering practice. <br />Summary of air pollution control features and activities: <br />Please see Exhibit M. Air pollution control will comply with state and county <br />standards and permits. <br />Summary of site history: <br />The site was originally an irrigated pasture/hay field, and then a state-operated pit <br />during the period 1950-1980. An estimated 35 acres (in two lobes, the main south <br />one of approximately 27 acres and 8 acres in a north lobe) was mined, in which up <br />to 30 feet of the estimated 45-foot depth of sand and gravel was mined. During this <br />period, no reclamation was done, and topsoil, overburden, and construction <br />materials were all removed from most disturbed areas. Since the permitting of the <br />modern permitted operation in 1995, a total of approximately 46 acres has been <br />affected, including 24 acres of pre-law disturbance. Modern mining began at the <br />north end of the permitted area (Areas 1 and 2 on Map C-4) and moved south, <br />although some pre-law areas (Area 18) remained. The remaining gravel (estimated <br />at 15 feet depth was mined in previously-disturbed areas, and the full depth <br />averaging 45 feet was mined on newly affected areas, after removal and <br />preservation of soil and overburden. Originally estimated at 25 years duration <br />(approximately 2.5 acres/year), the initial 12 areas have essentially been mined out <br />in only fifteen years (an average of 3.1 acres/per year). Each area was fully mined <br />out as work proceeded. <br />ASSUMPTIONS: <br />1. Annual production will be variable, but will be approximately that of the initial <br />15 years of operation (approximately 3 acres/year, with similar recovery of <br />overburden and fines. <br />2. Screenings and overburden will be used for backfill and attaining final grade. <br />3. Where present, soil ranges from 3 inches to 1 foot in depth, and averages 4 <br />inches. Much of the original permitted affected area (24 of 46 acres) had no <br />soil remaining at the time of the original permitting; other areas, although <br />technically undisturbed, had lost soil due to erosion. Based on the normal <br />Exhibits for 112(c) AM-02 Application -M-1994-108-2010- Page 14