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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 from the EPA (EPA 530 -R -94 -036) presents a <br />fundamental analysis for the potential of acid mine drainage. Basically, acidic waters are <br />formed by sulfide oxidation. Acid is generated at mine sites when metal sulfides are <br />oxidized. For example, pyrite (FeS2), when oxidized in the presence of water, creates <br />acids by the following reaction: <br />2FeS2 +2H20 +702 -)4H - + 4SO4 - + 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, form an acidic solution. <br />Conversely, common minerals for uranium ores and their chemical formulas are listed <br />below: <br />Carnotite: K2(UO2)2(VO4)2 3H20 <br />Tyuyamunite: Ca(UO • 5 -8H <br />Uraninite (Pitchblende): UO2 <br />Evident from the chemical formulas of these uranium compounds is the lack of sulfides. <br />Consequently, there are no acid forming properties evident in the commonly seen <br />uranium minerals of the Uravan Mineral Belt compared with other sulfide -based metal <br />minerals. <br />Since there are reducing conditions in uranium deposits, there is some potential for pyrite <br />deposition. However, it is not a major component like metal and coal deposits. Another <br />important issue presented by the EPA report is the evaluation of the neutralization of acid <br />by the alkalinity released when the acid reacts with carbonate minerals. According to the <br />EPA, this reaction can be an "important" means of moderating acid production. Salt <br />Wash sandstones are commonly calcareous meaning that calcium carbonate cements the <br />sand grains together forming sandstones. Any acid produced by pyrite would quickly be <br />neutralized by the waste rock. <br />6.1.2 Quantity <br />Currently the mine is not producing ore and there is no ore onsite. Once mining begins, <br />ore will be temporarily stored onsite for transport to an offsite processing facility. The <br />ore storage pad is located adjacent to the waste rock pile (see Exhibit C - Maps, Figure <br />C3) and occupies less than 0.25 acres. Ore will be mined at an approximate rate of 50- <br />150 tons per day. Ore from the stockpile will be hauled to the mill using a first in, first <br />out system. Once mining stops, ore will removed from the site within 30 days. <br />O'Connor Design Group Inc. U - 6 <br />