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5.0 EXHIBIT D -MINING PLAN <br />Mining will continue to be by front-end loader and trucks. The volcanic material is free <br />digging in nature with no blasting required. The mined material is loaded into the hopper of the <br />portable processing plant for dry screening. A variety of different sized products are produced, <br />with the minus 3/8-inch fraction being returned to the pit area as backfill. This fraction <br />comprised approximately 35 to 40 percent of the material mined and represents the uneconomic <br />part of the deposit. This material is placed into the excavated areas by use of dump trucks. It is <br />later pushed into place by a dozer. Because of the nature of the material, once placed back into <br />the pit area, it forms very stable, porous, and non-eroding shapes. <br />The existing permit assumed that all of the cinder cone would be mined and shipped off- <br />site. However, as presented in this amendment only approximately 60 to 65 percent of the mined <br />material can be economically sold into the market place. Therefore, the resulting post-mining <br />shape will resemble the original cinder cone, but generally lower in elevation. The <br />accompanying mining plan lays out the approximate configuration for the removal of the next 1 <br />million tons of material. This is not the entire cinder cone as shown by the map. It does <br />represent the next 15 to 20 yeazs of mining at the present mining rate, however, it is important to <br />note that the actual amount of material mined is wholly dependent on the market conditions. In <br />addition, it is also important to note that two primary products are made and sold; black scoria <br />and red scoria. These products occur in different locations within the cinder cone and therefore <br />mining may occur at several locations simultaneously depending on the products being made and <br />sold. <br />