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<br />r, <br />needed to demonstrate if the Salt Wash consists of one large aquifer or a series of <br />aquifers controlled by faulting, and if water quality in the Salt Wash aquifer(s) is <br />homogenous or is locally affected by mineralized zones. <br />• Most of the geohydrologic model is based on interpretation of the geology as mapped at <br />the surface, some observations of water levels in the underground mines. It is noted that <br />faulting is common under or near portions of the mining operations. In the event that <br />mining operations may affect ground water quality, studies should be conducted to <br />determine if any faults are capable of transporting leachates towards surface waters. <br />Other Items in the EPP to be addressed <br />BLM's review of the EPP has identified additional concerns, above and beyond those addressed <br />in the State Director's decision. In addition to providing the above baseline data, Denison must <br />address the following comments with regards to the EPP. <br />Environmental Geochemistry Investigation of Rock and Soil Material - Sunday Group Mines <br />Meteoric Water Mobility Procedure Analysis (MWMP) - 2.2.3 This section addresses the <br />potential of certain rocks to cause elevated levels of certain contaminants, even though the water <br />may not be acidic. In the description of the procedure, it states that de-ionized or distilled water <br />is used as the extraction fluid. <br />Comment: We would like to discuss the applicability of the MWMP method compared to other <br />methods such as the Synthetic Precipitation Leaching Procedure (SPLP) test, which uses an <br />extraction fluid which more closely resembles meteoric water than does de-ionized or distilled <br />water. Additionally, we would like further discussion of the fate and transport of any leachate <br />waters likely to be generated. <br />Wildlife - 4.1.1 Denison has concluded that "development rock areas where cadmium locally <br />exceeds the wildlife screening criteria are very small, relative to home and/or foraging ranges", <br />"Threatened or endangered species, or suitable habitat for those species, are not present .... <br />Therefore, complete mitigation of potential risks to all individual wildlife organisms is not <br />warranted.", and "It is unlikely that potential adverse effects to wildlife related to direct contact <br />risks would cause a significant impact to overall populations and community of the referenced <br />species." <br />Comment: Denison may not presume that no mitigation will be required if it can be <br />demonstrated that no Threatened or endangered species, or their habitat, are not present. Nor can <br />Denison presume that an impact that may affect some individuals but does not affect the overall <br />population is not of concern. BLM typically requires that any impacts, whether significant or <br />not, be mitigated wherever reasonable. <br />Denison must provide additional information to demonstrate how the potential exceedance of <br />cadmium will be addressed to protect wildlife, livestock, and human health. As an example, <br />Denison has not provided enough information for the BLM to be able to determine what the total