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Ms. Cheryl Signs Page 2 Barlow Pit M-74-092 May 31, 2007 Computation of evaporation under this plan was reduced during the snow cover periods. During periods of snow cover, which for this plan equates to the ice cover periods (median temperature <32°F), the State Engineer's Office (SEO) assumes that the historical depletions to the stream system are the same after construction of the pit because sublimation of the snow above the historically frozen ground equals the same amount of snow sublimation above the frozen pit. The snow cover period was assumed to extend from November 30 through February 20, which resulted in a reduction of the gross annual evaporation from 49.6 inches to 45.3 inches. As previously approved the credit given for the sub-irrigated alfalfa for this plan was based on the 3-feet depth to ground water, pending better site-specific information. The crop demand for alfalfa was calculated to be 36.8 inches using the modified Blaney Griddle method with Fort Morgan weather station data. Based upon a water table at 3 feet, the credit applied for this plan for pre-exiting sub-irrigated alfalfa was 27.6 inches (75% of 36.8 inches). Also with a 3-foot water table depth, effective precipitation (70% of total precipitation) in a sandy loam soil type was reduced by a factor of 0.80 (the factor fora 3-foot ground water table, calculated by averaging the sand and loam values, 0.95 and 0.66, at 3 feet), resulting in a corrected effective precipitation of 56% (70% times 0.80) of the total precipitation. The reduction in the amount of effective precipitation is based on the Food and Agricultural Organization of the United Nations' "Irrigation and Drainage Paper 25, Effective Rainfall in Irrigated Agriculture" by N.G. Dastane. Diversions from the batch plant well, permit no. 2104-F, are estimated to be 7.3 acre-feet per year. The resulting stream depletions from the operation of the well were lagged to the South Platte River using the AWAS program. Input parameters used to lag the depletions to the stream include a distance from the well to the river of 3,000 feet, an alluvium width of 3,500 feet, a transmissivity of 300,000 gallons per day per foot, and a specific yield of 0.2. The batch plant well is the only well on the batch plant site, and the well is used and permitted for commercial purposes including office use, lawn irrigation, truck washing, dust suppression, and concrete hatching. The well is metered and consumptive use is assumed to be 100% of well pumping. REPLACEMENT WATER The sources of replacement water to be used for this plan are 4.0 Riverside Reservoir and Land Company (RRLC) private rights owned by the applicant. In RRLC, four shares compose one private right. The RRLC private rights were formerly used for irrigation. The applicant owns two private rights that were formerly used to irrigate 24 acres of corn and alfalfa on the Brunelli property, in the W'/: of the S'/ of the SE'/., Section 28, Township 5 North, Range 59 West of the 6th P.M. in Morgan County. Dry-up of the land was confirmed by an affidavit included in the original 1990 SWSP report that attested, "This land is no longer in crop production." The other two private rights were obtained from the Roth property, which was used for supplemental irrigation of 120 acres located inthe NE1/4 of Section 11, Township 4 North, Range 56 West of the 6th P.M. All 16 shares (4 private rights) are documented on RRLC share certificate no. 1916, reissued on April 21, 2003. The historical use analysis for the RRLC private rights was calculated based on the diversion records for the Riverside Reservoir from 1971 to 2003. Based on the 2,505 private rights in the Riverside Reservoir Company, the delivery per private right was 16 acre-feet per year. Ten percent of the delivery was assumed to be surface return flows and forty percent was assumed to contribute to the ground water return to the river. Thus the total consumptive use credit associated with 16 shares (4 private rights) is 32 acre-feet per year. As in the previous plan, Dorn Ready Mix's 4 private rights will be traded with RRLC for recharge accretions credits ("recharge credits"). (Dorn Ready Mix is the owner/operator of the Barlow Pit.) This trade, which would be on an annual option, would allow Riverside to use Dorn's four private rights for irrigation in exchange for using Riverside's recharge credits to pay Dorn's replacement obligations. The recharge credits are generated pursuant to case nos. 90CW 181 and 91 CW066. RRLC will exchange any