2016-02-03_HYDROLOGY - M1985112 - Laserfiche WebLink

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Loloff Pit SWSP Page 2 of 7 January 27, 2016 this plan year. The estimated monthly depletions due to evaporation during 2016 are shown on the attached Table 1. Operational losses associated with mining activities will consist of water removed with the mined product and water used for dust control. Approximately 500,000 tons of material is projected to be mined in 2016. A 2% water loss is assessed as the material will be mined in a dewatered state and will not be washed. The quantity of water removed with the mined product is therefore estimated to be 7.36 acre-feet. A total of 4.10 acre-feet of water are estimated to be used for dust control purposes in 2016 based on a usage rate of 2,100 to 5,600 gallons per day. All water used for dust control purposes is assumed to be 100% consumed. The estimated monthly depletions due to operational losses during 2016 are shown on the attached Table 2. The IDS Alluvial Water Accounting System (AWAS) analytical stream depletion model was used to calculate the lagged depletions to the Cache la Poudre River. The model was executed in Effective SDF mode, using a stream depletion factor (SDF) of 60 days for the Loloff Pit site. The total lagged depletions were determined to be 16.19 acre-feet for this plan period, as shown in the attached Table 4. This amount includes lagged depletions resulting from past consumptive use at the site that are projected to impact the river during this plan period. Replacement Sources The replacement sources proposed for this operation consist of the yield from one share of the Greeley Irrigation Company ("GIC") during the irrigation season, and leased water from the City of Greeley ("Greeley") during the non-irrigation season. Greeley Irrigation Company Share Loloff owns one share of the Greeley Irrigation Company, Certificate No. 3391. A share of GIC water provides the shareholder with GIC direct flow water and Fossil Creek Reservoir water. The share was historically used for the irrigation of approximately 8.3 acres of land which have been removed from production as part of the share acquisition. A portion of the Greeley Canal No. 3 (WDID 0300934) was changed in Division 1 Water Court in case no. 1996CW658 based on a ditch-wide analysis by the Poudre Prairie Mutual Reservoir and Irrigation Company. The use of the subject ditch share in this plan shall be in accordance with the terms and conditions decreed in case no. 1996CW658, including monthly and annual volumetric limits on water deliveries and monthly return flow requirements. The decree in case no. 1996CW658 found that 519.7 shares were used to irrigate 3,501 acres with an average historical consumptive use of 5,358 acre-feet per year, which yields an average consumptive use credit of 10.31 acre-feet per share (5,358 acre-feet/519.7 shares). In paragraph 6.7.4 of the decree in case no. 1996CW658, future farm headgate deliveries of the 67.75 shares were limited to 1,712 acre-feet per year (25.26 acre-feet per share) and 12,631 acre-feet (186.43 acre-feet per share) in any consecutive 10 year period. Deliveries of Loloff's share of GIC water under this plan must comply with these limits. The historical return flows shall be maintained in accordance with the return flow factors identified in case no. 1996CW658. The return flows associated with the delivery of Fossil Creek Reservoir water that is attributable to the subject GIC share shall also be maintained in accordance with the surface and subsurface factors decreed in case no. 1996CW658. For projections of 2016 deliveries, the Applicant used the historic irrigation delivery attributable to GIC direct flow diversions of 18.6 acre-feet per share and the historic irrigation delivery attributable to Fossil Creek Reservoir deliveries of 1 acre-foot per share as determined in case no. 1996CW658 for the study period of 1950-1979. As specified in case no. 1996CW658, all