2015-01-12_REVISION - M1985112 (7)

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Mr. Jared Damns, E.I. Page 2 of 6 Loloff SWSP February 3, 2014 dedicated to the SWSP. To allow replacements to be made while the operator comes into compliance with DRMS requirements this SWSP will be renewed for 2014. The operator shall not expand the exposed surface area of groundwater under this SWSP until the site has been brought Into compliance with DRMS requirements. Additionally, at the time this SWSP expires, if there is no progress made on the operators behalf to bring this site Into compliance, the SWSP may not be renewed which would result in Cease and Desist Orders against the mine site. Depletions Consumptive use at the Loloff Pit site consists of evaporative and operational losses. The pit is being actively dewatered to allow dry mining. Evaporative losses are calculated based i on exposed ground water surface area of 2.0 acres due to the dewatering activities. Net evaporative depletions were calculated using a gross annual evaporation of 45 inches from the exposed water surface, with a credit of 9.97 inches for effective precipitation. No credit was claimed for ice cover periods. The net depletion of ground water due to evaporation of exposed ground water surface was calculated to be 5.84 acre-feet for this plan year. Operational losses associated with mining activities will include water removed with the mined product and water used for dust control. Approximately 200,000 tons of material is projected to be mined in 2014. A 2%water loss is assessed as the material will be mined In a dewatered state and will not be washed. The water removed with the mined product is therefore estimated to be 2.94 acre-feet. This water lost to dust control is estimated to be 3.60 acre-feet. The estimated monthly depletions due to evaporation and operational losses for 2014 are shown on the attached Table 1. Depletions at the Loloff Pit do not instantaneously accrue to the Cache La Poudre River, but instead result in a lagged depletion. A stream depletion model based on the Stream Depletion Factor(SDF)technique was used to calculate the lagged depletions to the Cache La Poudre River. An SDF of 60 days was used for the Loloff Pit site. The total lagged depletions for this plan period due to both projected and past consumptive use at the site are estimated to be 17.42 acre-feet, as shown on Table 1. Replacement Sources The replacement sources proposed for this operation include the Loloff Section 4 Ditch and leased water from Platte River Power Authority("PRPA")during the non-irrigation season and a lease of augmentation water from the Graham Drainage Ditch Company will supply replacement water during the 2014 irrigation season. Loloff Section 4 Ditch The applicant proposes to use the Loloff Section 4 Ditch (WDID 0300754) conditional water right for replacement purposes, if available. The Loloff Section 4 Ditch collects seepage and waste water in the vicinity of the Loloff Pit in the SW1/4 of the NW1/4 of Section 4, Township 5 North, Range 65 West. The Division 1 Water Court adjudicated a conditional water right for the Loloff Section 4 Ditch in case no. 87CW153 for up to 4 cfs of water with an appropriation date of March 15, 1987 (administration no. 50112.00000). The decreed uses for the Loloff Section 4 Ditch include irrigation and augmentation. According to the SWSP request, there is a flume and recorder to measure this water right,which has been approved by the water commissioner. The applicant proposes to use this water right first, if available, since it is a junior water right.