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INTRODUCTION <br /> Braun Environmental, Inc. has been retained to do a review of the rock properties on the Mineral <br /> Mountain project, located near Cripple Creek,Colorado as they relate to potential adverse <br /> environmental conditions. The testing was specifically designed to determine if the site has potential to <br /> produce free sulfur that could lead to generation of sulfuric acid,either exhibiting itself as acid mine <br /> drainage (AMD)or as acid leaching to disturbed rock areas and adjacent soils. <br /> BACKGROUND <br /> In these days of high regulation, it appears that we are continually put into the position of trying to <br /> prove the negative. The reasons are many but the demand for additional reporting remains. It is well <br /> known that the Cripple Creek District is generally non-acid generating from a regulatory standpoint, but <br /> the need for reporting is necessary. Within some of the mining districts in the State of Colorado, a large <br /> amount of free sulfur was produced during the primary volcanic activity and later hydrothermal activity <br /> that occurred during the cool-down. From a chemical perspective,the sulfur produced during the <br /> volcanic activity combined chemically with whatever it could find available,with its preference being for <br /> metals and one of them being iron to form iron sulfide(pyrite). In these volcanic areas that contained <br /> abundant quantities of sulfur,the original clues to the pioneer prospectors was the presence of <br /> naturally occurring low pH surface waters. <br /> As oxidation is currently stronger than sulfidization under Earth surface conditions,the destruction of <br /> sulfur-containing minerals from weathering and oxidation can produce free sulfur that presents itself as <br /> sulfuric acid (H2SO3). Certain sulfur containing minerals have a higher potential to produce sulfuric acid <br /> than others. The oxidation of iron sulfide (pyrite) produces free sulfur,while conversely in the same <br /> environment,the salts of the acid tend to bind the sulfur. A commonly occurring salt is the mineral <br /> compound calcium sulfate,commonly referred to as gypsum. In fact,calcium sulfate is currently the <br /> mineral preferred by government agencies and environmental professionals to bind sulfur, and even <br /> though the word sulfur sometimes conjures up fear,that particular sulfur-containing compound is <br /> welcomed,and even demanded by the government,as a commonly used building material in our <br /> homes. <br /> 1 <br />