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Mr. David M. Heintz Page 3 of 8 <br /> MMM South Platte Combined Replacement Plan <br /> January 8, 2015 <br /> cover industrial uses at these wells as follows: 70135-F (1657-RR), 70136-F (20583-R), 70137-F <br /> (19944-RR), 70138-F (20317-RR) and 70139-F (2819-FR). These well permits remain under Lafarge <br /> ownership. If MMM now has ownership of these wells then a Change of Ownership form (Form GWS- <br /> 11) should be submitted for each well. For the duration of this SWSP all metered use from these <br /> wells will be accounted under this plan. <br /> The water pumped for dust control is considered to be 100% consumptive. For the purpose of <br /> this SWSP a 4% moisture loss was calculated to account for the resulting moisture content of <br /> aggregate. Net evaporative depletions were calculated using a gross annual evaporation of 45 inches <br /> per year per NOAA Technical Report NWS 33. This was reduced by applying a credit of 9.8 inches for <br /> effective precipitation. As Riverbend East and West are near adjacent to each other these values <br /> were used for both sites. <br /> The mining sites are set back from the river, therefore, the depletions from the operations <br /> were not assumed to be instantaneous. Operational and evaporative depletions at the site were <br /> lagged to the stream system using a Glover analysis and the aquifer parameters shown below. After <br /> a new analysis by MMM, the Riverbend West site's X and W values were updated as well as the <br /> Riverbend East site's W value. To maintain consistency with previous SWSPs, MMM kept all <br /> depletions that occurred prior to this SWSP at the original lagging parameters but starting November <br /> 2012 are applying the updated lagging parameters shown in Table C below. <br /> TABLE C - IDS AWAS LAGGING PARAMETERS <br /> Site Name X (ft) W (ft) T (gpd/ft) Specific Yield <br /> Howe Pit 2,400 5,900 45,000 0.2 <br /> Riverbend West 2,200 5,200 170,000 0.2 <br /> Riverbend East 2,700 5,000 80,000 0.2 <br /> X-distance from well to river, measured from the centroid of exposed area <br /> W-distance from the aquifer boundary through the well to the river channel <br /> T-transmissivity of the alluvial aquifer (in gallons per foot/day) between the well and the river <br /> The lagged mining depletions are shown on attached Table 5. <br /> Replacements <br /> The proposed source of replacement water is (1) fully consumable water leased from the City <br /> of Aurora, (2) dewatering credits associated with mining operations at the Riverbend East site as <br /> explained in the following dewatering section. <br /> The Applicant has an agreement with the City of Aurora ("Aurora") whereby Aurora will <br /> continue to make releases of reusable effluent up to a maximum volume of 249 acre-feet for MMM's <br /> SWSPs. The reusable effluent is delivered from the Metropolitan Waste Water Treatment Plant <br /> (`MWWTP") (WDID 0200700) to the South Platte River. The applicant will account for a transit loss of <br /> 0.5% per mile from the MWWTP to the gravel pit sites. The transit losses for each site are shown in <br /> the table below. For purposes of the SWSP request, an average transit loss of 11% shall be used. <br />