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(6) Designated Chemical(s) and Material(s) Handling <br />6.1 Types of Acid and Toxic Producing Materials Originating Onsite <br />6.1.1 Source <br />A technical report on acid mine drainage prediction from the EPA (EPA 530 -R -94 -036) <br />presents a fundamental analysis for the potential of acid mine drainage. Basically, acidic <br />waters are formed by sulfide oxidation. Acid is generated at mine sites when metal <br />sulfides are oxidized. For example, pyrite (FeS when oxidized in the presence of water, <br />creates acids by the following reaction: <br />2 FeS2 + 2 H + 7 02 - 4 If + 4 SO + Fe <br />The hydrogen ions (H reduce the pH resulting in acidic conditions. The EPA report <br />notes that acid mine drainage is common in metal and coal mines. Commonly, sulfide (S) <br />minerals such as chalcopyrite, galena, and arsenopyrite, when oxidized in the presence of <br />water as shown in the above formula, produce acid drainage. <br />Conversely, common minerals for uranium ores and the chemical formulas are listed <br />below: <br />Carnotite: K 3 H <br />Tyuyamunite: Ca(UO2)2(VO4)2 5 -8 H <br />Uraninite (Pitchblende): UO <br />Evident from the chemical formulas of these uranium compounds is the lack of sulfides. <br />Consequently, there are no acid forming properties of uranium minerals compared with <br />metal minerals. Since there are reducing conditions in uranium deposits, there is some <br />potential for pyrite deposition but it is not a major component like metal and coal <br />deposits. <br />Another important issue presented by the EPA report is the evaluation of the <br />neutralization of acid by the alkalinity released when the acid reacts with carbonate <br />minerals. According to the EPA, this reaction can be an "important" means of <br />moderating acid production. Salt Wash sandstones are commonly calcareous meaning <br />that calcium carbonate cements the sand grains together forming sandstones. Any acid <br />produced by pyrite would quickly be neutralized by the waste rock. <br />6.1.2 Quantity <br />Currently the mine is not producing ore and there is no ore stored on the surface. Once <br />mining begins, ore will be temporarily stored on the surface for transport to an offsite <br />processing facility. The ore storage pad will be located on top of the waste rock pile (see <br />Exhibit E, Figure E4 - Maps) and will occupy less than 0.25 acres. Ore from the <br />stockpile will be hauled to the mill using a first in, first out system. Once mining is <br />finished, ore will be removed from the site within 30 days. <br />O'Connor Design Group Inc. T - 6 <br />