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Sievers Pit M-77-098 SWSP, Oldcastle SW Group, Inc. Page 5 of 12 <br /> August 7, 2025 <br /> Water Lost with Mined Product <br /> Groundwater will also be consumed during the process of mining aggregate. Before July <br /> 2009, the aggregate production at Sievers Pit occurred above the groundwater table; <br /> therefore, the decree in case no. 83CW65 did not account for the amount of water lost with <br /> the mined product, since there was no groundwater diversion. <br /> For the purpose of this SWSP, Oldcastle anticipates mining below the groundwater table a <br /> maximum of 225,000 tons of aggregate per year, resulting in an annual water loss of 3.31 <br /> acre-feet, assuming two percent (2%) water weight due to the dewatered state of the mine. <br /> An additional 2% of water is lost due to washing in the above-described 1 .9-acre surface <br /> water pond. Therefore, total water loss associated with the mined product is 6.62 acre-feet <br /> per year (both groundwater and surface water depletions). <br /> Dust Control <br /> The maximum amount of water used for dust control is anticipated to be 15.0 acre-feet per <br /> year, which is an increase of 5.5 acre-feet over the amount identified in Case No. 83CW65. <br /> Dewaterine <br /> Dewatering at this site will produce delayed depletions to the stream system. As long as the <br /> pit is continuously dewatered at a relatively constant rate, the water returned to the stream <br /> system should be adequate to offset the depletions attributable to the dewatering <br /> operation. Dewatering operations must be measured by totalizing flow meters that can <br /> accurately show the monthly volume of dewatered water that is pumped and returns to the <br /> stream. If dewatering at the site ceases, or is significantly reduced, the monthly meter <br /> readings will be used to determine post pumping depletions that must be replaced. At least <br /> 3 years prior to completion of dewatering, a plan must be submitted that specifies how the <br /> post pumping dewatering depletions (including refilling of the pit) will be replaced, in time, <br /> place and amount. Should it be determined by the Water Commissioner or Division Engineer <br /> that dewatering water is being diverted for any purpose by the operator and accounting is <br /> not adequate to show that one hundred percent (100%) of the dewatering water is returned <br />