2022-09-26_PERMIT FILE - M2022042 (6)

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Windsor East Mine, Exhibit G – Water Information September 2022 Page 4 | 11 1.3.2 Well Inventory In May 2022, a well inventory of the Affected Area and adjacent areas was conducted to identify wells near the project. The inventory included a search of the State of Colorado Office of the State Engineer database of wells located within ½ mile of the Affected Area (Table 1). The well inventory identified 25 constructed wells within ½ mile of the Affected Area. Figure G-4 enclosed shows the Affected Area and the constructed well locations on file with the Colorado Division of Water Resources. Wells located within 600 feet of the Lease Boundary The well inventory identified two wells completed in the alluvial aquifer within 600 feet of the lease-area boundary. The first is a monitoring well (Parsons MW-12) owned by Martin Marietta (permit # 280593) associated with the Parsons mine immediately to the east of the Windsor East property. Bedrock was encountered at 13 ft bgs and water was observed at approximately 6-8 ft bgs. The second is a monitoring well owned by Hall-Irwin Corporation (permit # 277000). It was constructed in 2007 and was screened from 4 to 15 ft bgs. Bedrock was encountered at 13 ft bgs and water was observed at approximately 2 ft bgs in 2007. Monitoring holes and wells are not a concern for dewatering impacts because neither are allowed to serve as pumped sources of water. Water supply wells located within ½ mile of the Lease Boundary In addition to the wells identified within 600 feet of the lease boundary, the well inventory identified two residential wells, eight monitoring/observation wells, three monitoring holes, and one general purpose well completed in the alluvial aquifer within ½ mile of the lease-area boundary. Permit number 89706-A Domestic/Residential well (89706-A) is registered to Brett T and Mary K Lauer. It was constructed in 1977 to a depth of 32 feet. It is located slightly more than 600 feet distance from the lease boundary on the northwest corner, and approximately 1,060 feet northwest from the nearest planned mining cell. The well is 5-inch diameter PVC, screened from 17 to 32 ft bgs, and was equipped with a pump capable of 30 gpm. The driller’s log indicates that water was encountered at 12 feet bgs in 1977. A 6-hr pumping test conducted in 1977 resulted in sustained pumping of 20 gpm and a pumping water level of 27 ft bgs (15 feet of drawdown, a specific capacity of 1.33 gpm/ft). Bedrock was observed at 27 ft bgs. Permit number 113762--A Domestic well (113762--A) is registered to M WaterCo LLC, although originally to Harold Long and Sons. It was constructed in 1980 to a depth of 25 feet. Water was noted at 12 ft bgs and bedrock was encountered at 20 ft bgs. A sustained pumping test of 30 gpm for 2 hours was conducted in 1980 with no recorded drawdown. It is located 1500 to 2000 feet distance from the lease boundary on the north side. A registered domestic well with a similar permit number (113762-) is associated with Harold Long and Sons Inc. The date of construction was not recorded, but the well inventory indicates that it was drilled to a depth of 30 feet, encountering bedrock at 20 ft bgs. This well shares nearly identical location and construction information (and permit number) with the well registered to M WaterCo LLC and seem to be the same well. The parcel that this well sits on is owned by GWIP LLC, the property owner for this reclamation permit application. Permit number 1472-R-R General Purpose well (1472-R-R) is registered to West Weld Ag Investors. This well was originally drilled for Allen Lamb with permit number 1472 before 1957 and listed as an irrigation well. It was replaced by well 1472-R at an unknown date to a depth of 15 ft bgs, with a 40 ft by 60 ft sump from which water was pumped at approximately 500 gpm. A permit application was received in 1981 to replace well 1472-R with a new irrigation well by West Weld Ag Investors with a proposed maximum pumping rate of 500 gpm and a planned depth of 50 ft. The registered UTM coordinates for the well indicate that it is located several hundred feet south of the Cache la Poudre river, but the description in the permit indicate that it is located 3,300 ft south of the northern edge of section 35 and 1,300 ft west of the eastern edge of section 35, and therefore may actually be located just north of the river near UTM 512260 E, 4476810 N. This location is approximately 1,200-1,300 ft west of the southwestern