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to be pushed towazds the toe with the final mining slope of 2H:1 V, which will maximize gravel <br />recovery and additionally will reduce the required backfill material to bring the slopes to a <br />3H:1 V slope. Secondly, this offset provides additional slope safety. This is demonstrated <br />through no evidence of slope failure during the life of the pits which have used similar <br />techniques in the same general azea. However, a failure would be governed by the internal angle <br />of friction of the material. This would limit the failed slope to an angle of 38 degrees or <br />~1.3H:1 V. This failure would not only stay within the permit area, it would stay within the final <br />slope envelope. <br />The maximum total tonnage sold from the site in any one calendar year is 378,750 tons, though <br />the expected annual average is 252,500 tons. The raw material will be sold in three products: <br />road base, concrete, and asphalt. A break down of the product tonnages and mined tonnages can <br />be seen in Table D-1. The total disturbed area is 159.76 acres. A breakdown of the estimated <br />areas is included in Table D-2 <br />Table D-1 <br /> Average Annual Product Distribution <br />roduct Tons Sold % Reject Rate Tons Mined <br /> {Naturals) <br />oad Base 200,000 0% 200,000 <br />Concrete 37,500 10% 41,667 <br />sphalt 15,000 40% 25,000 <br />otal 252,500 5% 266,667 <br />Prior to mining below the water table, a sediment pond will be created in the northwest comer of <br />the permit area. This pond will handle the 10 year event from Phase 1. The sediment pond will <br />only need to contain an event before mining begins. Once mining commences, the pit will serve <br />as the sediment pond. Due to wet conditions the pit will need to be pumped. This water will be <br />collected in a sump in the northwest comer of Phase 1. The sump will have a berm surrounding <br />it to detain fines. The sump will be allowed to drain into a settling pond, which will allow for all <br />sediments to settle out of the dischazged water. The settling pond will be approximately 20 feet <br />wide and 100 feet long. From the settling pond, the water will overflow into a discharge culvert <br />which goes under the county road. The culvert will be 20" in diameter and will be more than <br />Anderson Pit February OS D-2 <br />