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<br />willbe geatei annual pitinflow and a correspondingly Beater need forrelease of"mitigation <br />water" to offset such increased aquifer dewatering. <br />Based on our recent conversations with engineers at the New Horiwn Mine, we have <br />been led to believe that although the new pit is deeper, it still affects the same "shallow <br />overburded' aquiferthaz formed the basis forthe decrce's conclusion ofno injury to adjacent <br />well owners. Thus, the former question may not be a matter of concern. The latter question <br />raises the additional issue of whether the 48.4 acre-feet of mitigation water previously <br />devoted to the original minepit can now be shifted [o cover mitigation needs associated with <br />the new pit The answer to this issue depends, in part, upon whether or not there is any <br />ongoing dewatering associated with the original mine pit Assuming that the existing <br />mitigation water could be shifted to weer dewa[ering az NH-2, there may be sufflcieat <br />available water, taking into aewunt unused consumptive use credits, to mitigate any <br />increased pit dewazering at NH-2. However, there would remain wncenrs with whether the <br />location of Ponds 008-015 and the High Line Canal turnouts would enable releases of <br />mitigation water in appropriate locations to prevent injury to other rights. The decree <br />requires. that adverse impacts of pit dewatering must be mitigazed by releasing water from <br />the High Line Canal and/or the ponds ` m the vicinity" of potentially impacted water users <br />(as discussed in SectionIB.(3), above). <br />Third, another wncerti raised by. the larger active mine pit relates to whether the <br />decree's calculation of the amount of water required for industrial uses for wmpaction and <br />dust suppression would be sufficient to augment such uses atNH-2 without having to amend <br />the augmentationplan. Thedecreeprovidesthatwaterrequirements~forcompadionanddust <br />suppression are 100% wnsumptive and were "estimated based on anticipated overburden <br />handling procedures at each mine." Decree y 6.B.(2)(d). Given that the current mine is <br />larger than its predecessor, such "overburden handling procedures" may have increased or <br />changedto such au ex[entthatthe decree's estima[eAwater requirements for wmpaction and <br />dust suppression would no longer be awurate to rover such 100% consumptive depletions. <br />Again,however,ihere may be sufficientaugmentationwatufromlreed-upconsumptiveuse <br />credits previously devoted to industrial water use atNH-1 and from unused consumptive use <br />credits order the plan to adequately rover such increased depletions. <br />Finally, the decree states that "surface runoff' captured by the ponds may wnstitute <br />the out-of-priority storage of water which, if the Division.Engineer detemunes is causing <br />injury, must be compensated for by releases of wnsumptive use credits and/or water from <br />the ponds (as discussed in Section I.B.(5), above). Thus, another quantitative wncern is <br />whether the location of Ponds 008-015 are such that the ponds ace likely to capture surface <br />runoff during the irrigation season, which would thus constitute out-of-priority storage; and <br />also whether applicable water quality requirements may prevent Western Fuels from <br />]0 <br />• <br />REVISED MARCH 2006 Attachment 2.05.3(3)-16-19 <br />