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JUI,- 5-95 WED 229 PM TESSF~CT PP,ODUCTIONS FAX N0. 3~~79713 P, 7 <br />continues to the present date (July 3, 1995), albeit at a much- <br />reduced rate estimated at one to two quarts per minute (qpm). <br />This is infected From observadon of surface water flow near the <br />mouth of the edit, coupled with tbe fad that the water level behind <br />the bulkhead was nearly the same as before, at about nineteen to <br />twenty inches £reeboard, with significant leakage continuing at <br />various points around the bulkhead. <br />The implications of these observations are obvious. The Hazel A <br />will take on water at significant rates during any extended wet spell <br />such as we Lad in May 1995. To nraiatain froeboard the edit will <br />gave to be pumped, presumably to the tailings pond, and this at <br />just the time whm one would least wish w have additional water <br />delivered to that place. This condition can continue far days m <br />weeks, and accompanying climamlogical conditions can be such <br />that little or no net evaporation is occurring from the tailings pond. <br />It is difficult to see Low a zet+o-discharge posture can be maintained <br />mdet suet condidans absent frequent to continuous pumping and <br />a very substantial pond freeboard. It is also difficult [o see how <br />edit discharge can be prevented by any passive system short of a <br />full edit seal; this however would preclude easy access for periodic <br />cleanout of tailings slimes as contemplated in the present decant <br />line approach. Full seal would also almost certainly requue keying <br />the seal into the floor, walls end roof of the edit, possibly <br />supplemented by some grouting of the surrounding rock. <br />Looked at solely from an environmental perspective, it appears that <br />rema+~~ng pond slimes must be removed from Ute Hazel A and its <br />use as a pond overflow reservoir must be abandoned. It is an open <br />question at present whether residual water flows from the open edit <br />are of acceptable quality. Doubtless some sampling will need to <br />be done under quiescem conditions afocr alit cleanout. <br />The alternatives, however, are also unattractive. Either the dam <br />must be raised further, at considerable financial and environmental <br />cost, or the tailings emplacement must be limited, thus reducing <br />impoundment working life. A thirri aLetnadve of worse earisls, <br />that of water treatment and permitted discharge. Costs of this, too, <br />are likely m be unatttarxive if not pmhibidve. <br />In Reference 5, Item 10, we tmderscored the need for a thorough, <br />competent engineering review of the total milling system at the <br />(}old Hill Mill. We continue m believe this will benefit all parties, <br />the earlier the review, the greater the benefit. Of particular <br />relevance in light of the issues discussed above is the matter of <br />