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<br />John Hardaway <br />-2- <br />June 6, 1995 <br />These parameters are necessary in order to indicate what the baseline water <br />quality is for LDS 1 through 5. At present, only LDS 3 is in an area of process <br />solution application. Also, a portion of the underdrain system is beneath a <br />portion of the leach pad facility where process solution is being applied. Water <br />quality baseline data shall be collected for 5 quarters for the long term, and <br />weekly for 8 consecutive weeks for near term. Also included in this baseline <br />water quality data will be one complete suite analysis from the LDS system and <br />the underdrain system. All groundwater monitoring points shall not exceed <br />.2 mg/I WAD cyanide concentrations. The Division will assume containment has <br />been lost if the .2 mg/I is exceeded in the G.W. monitoring wells. <br />If the short term data for LDS 1 through 5 shows similar results, the Office will <br />consider allowing the operator to combine the data and submit the averages. <br />In the interim the operator agreed to determine where the water in the leak <br />detection trenches is coming from. Since only a small portion of LDS 3 trench is <br />in contact with the active leaching process, and since the leak detection trench <br />was not designed to capture surface runoff, and since water has been detected <br />in the sumps, you need to provide a reasonable explanation for the additional <br />contributions of water to the system (LDS). We have detected water in LDS 5 <br />and 2. The operator stated that the water in the trenches was due to <br />precipitation events, and agreed to determine how much was being <br />contributed to the trenches from a particular event. You also agreed to provide <br />how to properly determine the volume in the low volume collection system, <br />and the pool areas volume in accordance with Figure 4.1 by June 15, 1995. <br />You should also included in this submittal the maximum allowable leakage rate <br />for the pool area. <br />As one of your criteria for release of reclamation responsibility, a .2 mg/I WAD <br />cyanide concentrations will have to be met. This standard will apply at all the <br />ground water and surface water monitoring points before financial warranty is <br />released. Please refer to our Condition No. 20 (your Commitment No. 40). <br />If you have any questions please give me a call. <br />Sincerely, <br />/~/~ .~~ <br />~,z <br />Bruce Humphries <br />Mineral Program Supervisor <br />cc: Berhan Keffelew, DMG ~ <br />Jim Stevens, DMG <br />Mike Long, DMG <br />Harry Posey, DMG <br />Jim Pendleton, DMG <br />M:\OSS~ammlWmmltbK <br />