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Third Adequacy Letter, Amended CN-01 I 9 <br />May Day Idaho Mine Complex <br />approved disposal location and the recycled water returned by pipeline to the <br />flotation cells. The proposed disposal location was shown on Figure D-1a. <br />Figure D-1a was not included in the April 18 submittal. Rather, the April 18 <br />submittal provided Figure D-1B, which showed the proposed underground <br />location for tailings disposal. The text of Figure D-1B is not legible, but the <br />general location for tailings disposal is sufficiently shown to be readily identified <br />on other mine maps which were not submitted by the Applicant. <br />By comparing Figure D-1B to other mine maps the Division determined the <br />proposed underground location for tailings disposal is approximately 2,100 feet <br />underground. <br />Therefore, the Applicant's response indicated tailings would be dewatered at an <br />underground location and not at surface, as stated by the Applicant. Additionally, the <br />dual lined slurry pipeline and recycle water return pipeline would be approximately <br />2,100 feet long rather than the 50 foot long pipelines stated by the Applicant. <br />The mill facility and the associated pipelines and tailings disposal location(s) are <br />Environmental Protection Facilities and subject to the most rigorous environmental <br />protection regulations. Pursuant to Rule 6.4.21(10)(a), the Division had previously <br />requested design specifications certified by a licensed professional engineer for all <br />Environmental Protection Facilities intended to hold, convey, contain, or transport <br />designated chemicals, including process solutions and mill tailings containing designated <br />chemicals. The Division clarified the certified designs must address the redundant <br />containment measures required under Rule 6.4.21(7)(e). (DRMS preliminary adequacy <br />letter, dated March 15, 2011, adequacy item number 39) <br />Rather than submitting the required certified designs the Applicant's response was <br />cursory and sufficiently contradictory to confuse what is intended. The Applicant's <br />response to the adequacy issue is not acceptable. Please answer the Division's <br />adequacy questions in a clear and concise manner. Please clarify what is intended. <br />19. Please clarify the statement appearing on page 3 of Attachment E-1, Exhibit D, Mining <br />Plan, of the amended application, <br />"Dry stacked tailings disposal or submerged tailings will be implemented at the <br />May Day Idaho mine complex. (See Figure D-1a for disposal site options. Tailings <br />(150-200 mesh grind) will be dewatered after the material is transported to the <br />approved disposal location." <br />Specifically, please clarify the apparent definition of "tailings" as being limited to 150- <br />200 mesh size fractions. Please clarify the fate of tailing particles larger than 150 mesh <br />and smaller than 200 mesh, if any. <br />20. On pages 1 and 2 of Attachment E-1, Exhibit D, Mining Plan, the application identifies <br />three staging areas. One of the staging areas, located adjacent to County Road 124, is