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<br />June 10, 2020 Permit No. M-1977-410 Amy Eschberger Environmental Protection Specialist Colorado Department of Natural Resources Division of Reclamation, Mining and Safety 1313 Sherman Street, Room 215, Denver, CO 80203 <br />RE: Cross Gold Mine, Permit No. M-1977-410, Technical Revision No. 7 (TR-07), <br />Preliminary Adequacy Review Dear Ms. Eschberger, This letter is provided by Grand Island Resources (GIR) in response to the Adequacy Review letter from the Division of Reclamation, Mining and Safety (DRMS) dated May 28, 2020 in conjunction with Permit No. M-1977-410, Technical Revision 7 (TR-07). After reviewing the materials submitted, DRMS identified several adequacy items that require additional information before an approval of TR-07 can be issued. Based on our understanding, these items are summarized as follows (in italics), along with a reply or response from GIR as appropriate: 1) Adequacy concerns related to the stability analysis that must be addressed are <br />expressed in an attached Memorandum from Peter Hays, DRMS, dated May 27, <br />2020. These concerns include: <br />a. The minimum acceptable Factor of Safety (FoS) for stability of the slope <br />must comply with Section 30.4 of the Policies of the Mined Land <br />Reclamation Board (MLRB), effective May 16, 2018. <br /> GIR understands that the minimum acceptable factor of safety for long-term static stability is 1.5 for generalized, assumed, or single test strength measurements, and 1.3 in the case of a sufficient number of strength measurements to define the variability of the material being tested and the extent of disturbance, per MLRB policy. Alternatively, the permittee may submit stability analyses based on site-specific engineering analysis performed in consideration of good practices as specified in relevant industry guidelines and/or professional standards and reviewed by DRMS on a case-by-case basis. Section 30.4 of the MLRB policies also points out “It should be noted that most industry standards assume a permanent slope configuration, ignoring the temporary conditions that are frequently observed in the mining industry”. <br />b. Pursue a structure agreement with Boulder County for Caribou Road with <br />an acknowledgement of the proximity of the road to the collapse void. GIR has this agreement “structure agreement with Boulder County for Caribou Road” in hand <br />