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Steve Nguyen March 21.2007 Weld County will irrigate two acres of sod and seven acres of native grass around the reclaimed pond at the Weld County Service Center. This area will be irrigated using water pumped from the lake during the growing season. According to a Modified Blaney-Griddle analysis the potential crop consumptive use for the two acres of sod is 4.1 acre-feet and the potential crop consumptive-use for the seven acres of native grass is 11.2 acre-feet. Since the irrigation occurs directly around the reclaimed pond the plan assumes that the return flows will return to the,river in the same timing as the depletions. Consumptive use from the operation of this site consists of 4.4 acre-feet of water lost in product (4% moisture of 150,000 tons of raw material), 1.2 acre-feet for on-site dust control and 145.9 acre-feet of evaporation from 56.8 acres of lake surface exposed after December 31, 1980. The total consumption at this site from mining operations and irrigation is 166.8 acre-feet. The depletions from evaporation and operational losses were lagged to the stream using a Glover analysis and assuming a distance to the stream of 250 feet, distance to the impermeable boundary of 6,600 feet, transmissivity of 50,000 gal/day/ft and specific yield of 0.2. The depletions from irrigation were also lagged to the stream using a Glover analysis and assuming a distance to the stream of 800 feet, distance to the impermeable boundary of 6,600 feet, transmissivity of 50,000 gpdfft and specific yield of 0.2. The Applicant has provided a monthly schedule of lagged actual depletions to the river system, together with a schedule of replacement requirements. This SWSP accounts for actual depletions determined to accrue to the steam system during this plan period. REPLACEMENTS The sources of replacement water are 3.75 Rural Ditch shares owned by Weld County, storage of excess credits in Varra's 112 Pit and fully consumable water leased from SVLH. Weld County has obtained a lease from SVLH for 22.9 acre-feet. The amount leased from the SVLH includes a transit loss of 0.25% per mile for the 12 miles between the pit location and the discharge point for the SVLH water. This plan proposes to store excess river credits attributable to the 3.75 shares of Rural Ditch. The excess river credits which accrue to the stream system in June, July and August will be stored in the Varna Pit No. 112, which lies directly to the south of the Hokestra Property and across the Rural Ditch. It is estimated that 78.6 acre-feet of excess credits will be available for storage during this plan period. According to the reservoir operations model for the 112 Pit, the water placed in the 112 pit will incur an evaporative loss of 5% or 3.9 acre-feet. The 112 Pit has access to a ditch headgate, which will be used to deliver the excess river credits to the lined reservoir for storage. The stored water will be released from the pit to cover depletions from the site as shown in attached Table No. 8. below: The 3.75 shares of the Rural Ditch were historically used to irrigate the four farms listed Adler Farm The Adler farm was historically irrigated using 5 shares of the Rural Ditch of which Weld County owns 1 share. The 5 shares were historically used to irrigate 168 acres of corn and 63 acres of Pasture grass, all of which has been taken out of production. The historic consumptive use of the 5 shares was determined to be 209.6 acre-feet. The prorata historic consumptive use for 1 share is 41.9 acre-feet.