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Division of Water Resources. ' <br />1tE.•. . <br />,GreeleyPitSWSP. .:.::..: - .,. . <br />Miry 25,:2010 <br />Pa" ' Z-of 4. ` <br />IIIPLETIONS ". . <br />:Consumptive uses atiheGreeley Pit consist of evaporative and operational losses. Evaporative <br />Loses are calculated. Based on exposed:groundwater = sorface area.. As.: shown on Figure "2, of <br />the:67:6 .acres`currently exposed; : approximately 31-.0 ? acres were. exposed prior: to.1881 <br />(corresporadu?g to the 21.2 acre southwest pond, the 5.7 acre southeast pond," and 41 acres of_the <br />.40. acre north pond). " Also, according to Joe Kuntz of. Mountain Constructors <br />(who "o " <br />:. :: ted the <br />"gravel pit .during. the 1980 t6:1981. period) there was 4n additional 8.8 acres of excavated area; <br />which Js not shown as being filled with groundwater in the aerial photograph in Figure 2 because . <br />thid' area was being Owatered at the time.,'.He believes that dewatering may have ceased and the <br />additional -8.8 : acres would"have filled with -exposed grotindwate; <br />prior .to January l; 1981:. In <br />accordat Ge-with DWR,pol", Hiner requests a credit for the pre-1981 exposed area; this r'csults. <br />in.a cuireot net exposed area of 27.$"06res: No additional groundwater- will be exposed during, . <br />the.plats period. = <br />According to NOAA,Teehnical Report NWS" 33, the gross evaporation for the area is 45 inches. . <br />Evaporation was distributed .on.a monthly basis pursuant to values recommended by the DWR = <br />for. elevat ans below 6,500 feet: MSL," .`Accounting for. an effective precipitation credit.and <br />anticipated - ice-covered: periods," "the annual. net. evaporation is estimated to equal - 33:1.1 inches.. <br />Hiner antiaipat that no deW.atenng will occur during WY 2010; therefore, for anet- exposed <br />water surface. of 27.8 acres, the evaporatiye.loss during the plan. period is estimated: to' equal <br />= 70.22 -acre-feet as shown3n Table No. 1. <br />' Qperatioiial losses. at the pit will occur from water removed with the mined-product -and "water. <br />-used for dust.. control. This operational consumptive use is quantified in Table .No. 2.. -Hiner <br />expects that no more "than 100,Q00 tons of material will be -mined. in WY 2010 according to <br />. <br />-the monthly percentages .provided -in Column (A) of Table No: 2.. The material. will be: mined <br />above the :water table, and. the material will not be washed. Pursuant. to the State Engineer's <br />::: `-guidelines, the assuzxied' moisture content" is294 by weight, but 0% is ch the <br />arged because moisture .is 'not-a_ groundwater diversion. The water removed with the mined product is therefore <br />estimated to.be zero ac-ft in the plan period. <br />;Water.-withdrawn: from the pit: is' also. used for dust control: Hiner -estimates that a minimal <br />oun'-d-4 st control water will be used, from March to October, corresponding to.1.00 ac-ft, <br />.::per year.: As shown in Column •(E) of Table No. 2, the" total- operational consumptive use is <br />:estimated. to be 0.9 ac-ft during the-plan period, <br />'Total Augmentation Requirement ' <br />Tlie: total :augmentation :requirement, de ftned. as the sum of the. evaporative. consumptive use, <br />operational consumptive .use, and GIC return flow obligation, is estimated to equal 71.12 sere- <br />feet "during the plan period. The: Greeley Pit is directly -adjacent to the Cache la Poudre River and <br />therefore the depletions. are. considered instantaneous - and . do not have a lagged impact to the " <br />river...