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CLEAR -fes AkCREEK ASSOCIATES March 9, 2015 Transmitted by E-mail Mr. Miguel Hamarat Climax Molybdenum Company — Henderson Operations 1746 County Road 202 Empire, Colorado 80438 Subject: Ute Park Extraction Wellfield Project - Technical Revision 23 (TR -23) Certification, Henderson Mill, Permit No. M-77342 Dear Mr. Hamarat: AJAX Mountain Enterprises LLC (dba AJAX Ltd) and Clear Creek Associates PLC (Clear Creek) are submitting this letter certifying the installation of extraction well MLEX-1, in accordance with the requirements of TR -23, dated May 20, 2014. Per TR -23, a new extraction wellfield is being installed east of the Henderson Mill Tailing Storage Facility (TSF) 1 -Dam. The existing extraction wellfield permitted under TR -10 will eventually be replaced by this new wellfield as it is fully built - out over the next several years. The construction of the wellfield is anticipated to be completed in three phases, as shown in Figure 1. This will allow for its effectiveness to be evaluated as the project progresses. Construction of Phase I began in July 2014 and was completed in January 2015. It involved the installation of one extraction well, MLEX-1, and associated infrastructure, including piping, electrical, and instrumentation. A shallow/deep pair of monitor wells (MLGW-21/MLGW-22) were also installed east (downgradient) of the extraction well (Figure 1). These are not considered an environmental protection facility (EPF); however, they will be used to monitor the effectiveness of the extraction wellfield. The Phase I extraction well, MLEX-1, was drilled to a depth of 90 feet, penetrating the base of the Quaternary sediments aquifer system at a depth of 80 feet. The extraction well was completed with 8 -inch stainless steel casing. Well screen consisting of 0.125 inch stainless steel wire -wrap casing was set from 21 to 78 feet. An As -Built drawing for MLEX-1 is included as Figure 2. The only deviation from the preliminary design is that the length of the blank casing sump at the bottom of the well was increased from 5 to 10 feet. The extraction well was developed by swabbing and bailing, and pumping using both a down -hole electric submersible pump and suction pumping using a surface pump. Following well development, an eight-hour step -test and 48-hour constant rate pump test were performed on MLEX-1. Testing indicated the well is generally efficient at test rates up to 70 gpm.