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Mr. Douglas Dowling Page 2 Barlow Pit M-74-092 April 5, 2004 Computation of evaporation underthis plan was reduced during the snow covered periods. During periods of snow cover, which for this plan equates 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. During the plan review, the SEO also discovered that the past credit for the pre-existing sub- irrigatedalfalfa had previously been overstated. To verify the appropriate credit, the average depth to the ground water table needs to be established. As noted in the accounting section of the July 11, 2003 draft report submitted by Cheryl Signs Engineering on Dorn Ready Mix's behalf, monthly measurements will be taken at the pit this plan year to establish the average depth to the water table for the year. The well construction report for well permit no. 1265-R-R, owned by Dorn Ready Mix and located in the same quarter section as the Barlow Pit, shows the static water level at 6 feet below ground surface. Measurements at the pit in June of 2003 (high water table season) showed the depth to ground waterat 3 feet below ground surface. The 3-feet depth to ground water was used for this plan year, 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 year 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% times 0.80) 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% of the average precipitation. This is based on the Food and Agricultural Organization of the United Nations' "Irrigation and Drainage Paper 25, Effective Rainfall in Irzigated Agriculture" by N.G. Dastane. Including the batch plant well, well permit no. 2104-F, in this plan adds 4.2 acre-feet of lagged depletions forthis plan year. Batch plant well replacement requirements were based upon an SDF of 100 days and using 20-year-average data available to model the years from 1995 to 2000, reported data for 2001 and 2002, and 2002 data as an estimate for 2003. The batch plant well, as the only well on the batch plant site, is the water supply and is 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 (representing reservoir storage) owned by the applicant and the full pro rata share for 4.0 private rights of RRLC recharge accretion credits ("recharge credits") for the plan year. 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 com and alfalfa on the Brunelli property, in the WY: of the S%ofthe SE'/<, Section 28, Township 5 North, Range 59 Westofthe 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 in the NE1/4 of Section 11, Township 4