2019-07-30_PERMIT FILE - M1996052

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L.G. Everist Combined SWSP Page 6 of 16 March 14, 2018 Replacements Saint Vrain Creek L. G. Everist claims to own 3.31 shares of the Rural Ditch Company. Of the 3.31 shares of the Rural Ditch (WDID 0600551) water, 1.41 shares will be available for replacement in this SWSP for 2018 and 2019. A historical consumptive use ("HCU") analysis was submitted to this office in 2016. The period of analysis selected for the 1.41 shares included in this SWSP is 1950 through 1997. For this period, diversion records for the Rural Ditch were downloaded from Hydrobase using Use 1 (irrigation) and Source 1 (river). Daily diversions for the Rural Ditch were adjusted to include only the diversion up to 83 cfs, the sum of the two senior Rural Ditch irrigation rights. The 58-year study period is representative of wet, average and dry years evidenced in the Saint Vrain Creek and the South Platte River Basin. The 1.41 shares of the Rural Ditch were historically used on the 77-acre Lohmann property located in the NW1/4 of Section 6, Township 2 North, Range 67 West of the 61h P.M. (Figure 1). The land historically irrigated by the 1.41 shares is the same land that is currently being mined at the Carbon Valley Pit. Thus all of the lands historically irrigated by the subject shares have been permanently dried up due to the mining operations. The HCU analysis conducted for the 1.41 Rural Ditch relied on the following method and assumptions: • Modeling using the State CU and the Modified Blaney-Criddle method with the TR-21 crop coefficients. • The total structure daily diversion records were limited to the period of proposed April 1 through October 31. • Soil Conservation Service methodology for calculation of effective precipitation. The soils on the Lohmann property include predominantly Heldt silty clay on 1 to 3 percent slopes with some Aquolls and Aquents gravels. Available water content of the soils as reported by National Resource Conservation Service ("NRCS") Web Soil Survey averages 0.155 inches per inch. • Assumed ditch loss of 15 percent. • Temperature and precipitation data were taken from the Longmont 2 ESE climate station (ID 5116). The Longmont climate station is located approximately 7 miles from the Lohmann property. • From a 1999 aerial photo, approximately 34 acres were identified as irrigated on the Lohmann property. This quantification corresponds with information provided in an affidavit regarding the usage at the Lohmann property (attached to this letter). There appeared to have been additional consumptive use on the lands marked as questionable on the figure included with the affidavit. However, these lands are not included in this HCU analysis. • As noted in the affidavit the land was flood and furrow irrigated and the crops grown were alfalfa, corn and barley through 1972 and alfalfa and corn thereafter. • The Applicant proposed a maximum irrigation efficiency of 55 percent for flood and furrow irrigation for the crops grown on the Lohmann property. • Return flows assumed to be 33 percent ground water and 67 percent surface water. Ground water return flow was analyzed using AWAS software based on the Glover methodology according to the parameters summarized in Table F. Table F- Summary of Glover Parameters Distance from Farm Distance from boundary Transmissivity Specific Yield to River (ft) to River (ft) (gpd/ft) 2,000 4,173 50,000 0.2 The HCU results are summarized in Table G.