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CLEAR <br />CREEK <br />ASSOCIATES <br />February 23, 2015 Transmitted by E -mail <br />Mr. Miguel Hamarat <br />Climax Molybdenum Company — Henderson Operations <br />1746 County Road 202 <br />Empire, Colorado 80438 <br />Subject: Groundwater Quality Assessment Update, Henderson Mine, Permit No. M -77342 <br />Dear Mr. Hamarat: <br />AJAX Mountain Enterprises LLC (dba AJAX Ltd) and Clear Creek Associates PLC (Clear Creek) are <br />submitting this letter to summarize field investigations recently conducted to further evaluate <br />groundwater conditions in the vicinity of the Mine facilities. Monitoring and reporting requirements <br />for the Mine are pursuant to the Division of Reclamation, Mining, and Safety (DRMS)- approved <br />Henderson Groundwater Management Plan (GWMP), formally submitted as Technical Revision 16 <br />(TR -16) to the Henderson Mine and Mill Reclamation Permit No. M- 1977 -342 (Henderson, 2012). <br />This investigation was initiated as a result of low pH measurements in Point of Compliance (POC) <br />well MNGW -1 in 2012 and 2013, which were reported to DRMS per the GWMP requirements. <br />Investigations were performed in September 2014 in general accordance with recommendations in <br />the Groundwater Quality Assessment Technical Memorandum submitted to DRMS in December <br />2013 (AJAX /Clear Creek, 2013). The investigation included the drilling, logging, installation, and <br />testing of two monitor wells in the alluvial deposits north and west of existing POC well MNGW -1 <br />(Figure 1). <br />The two monitor wells, identified as MNGW -3 and MNGW -4, were drilled through the entire <br />thickness of the alluvial sediments, which were approximately 20 to 25 feet thick. The geology <br />consisted of alluvial sediments consisting of boulders, cobbles, gravels and sands with varying <br />amounts of clay. Competent Precambrian granite bedrock was encountered below the sediments. <br />The monitor wells were constructed with 4 -inch PVC casing and were screened over the bottom 10 <br />feet of the alluvial sediments. Well construction information is summarized in the table below. As- <br />Built drawings for the new wells are presented in Figures 2 and 3. <br />The new monitor wells were developed by swabbing and pumping in accordance with standard <br />operating procedures. Post - development depth to water ranged from 9.1 feet below ground surface <br />(bgs) in MNGW -3 to 3.7 ft bgs in MNGW -4. Based on initial measurements, the estimated <br />groundwater flow direction in the vicinity of the new wells was northeast towards the West Fork of <br />Clear Creek. Following well development, falling -head aquifer tests were performed at each well. <br />