2023-05-25_PERMIT FILE - M2022048 (18)

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l [ EXHIBIT G WATER INFORMATION Introduction The site is located about 1 . 5 miles west of Platteville, Colorado. Please refer to EXHIBITB-VICINITY MAP for the property configuration and the relationships to surrounding geological features . The site is bordered on the south, west and northwest sides by irrigated agricultural lands and on the east and part of the northeast side by the South Platte River. There are 2 irrigation return flow ditches that cross the property and other onsite temporary agricultural feeder ditches that carry water to the fields being irrigated. Two center pivot irrigation systems are fed by wells owned by L.G. Everist, Inc . There are 7 registered irrigation wells, one domestic well and 6 piezometers on the property. Within 200 feet or the permit line there is 1 Domestic and one Geothermal wells located in the southwest corner of the site . Based on regional groundwater studies and the experience gained by L.G. Everist, Inc. during numerous previous permit applications they have found that slurry wall liners mitigate any impacts to groundwater on nearby areas surrounding a lined reservoir . Ground water in this area tends to flow from the west towards the river, the depth to water on the flood plane level averages feet below the surface and along the western terrace deposit the depth to the water table is -2_--19 . 5 feet . Data for the monitoring well information collected thru the month of submittal is shown on TABLE G-2 ON SITE GROUNDWATER MONITORING DATA. if any significant groundwater changes do occur, they can be mitigated as discussed below. In April 2023 a Groundwater Model (GWM) was prepared by Schnabel Engineering to provided potential impact information of the ground water levels by installing Slurry Wall liners around the reservoirs . That report is provided at the end of this exhibit . In addition, Molen and Associates was asked to prepare a Water Quality Monitoring Plan for the permit area . That plan is also included in this exhibit . These reports are used in the following text to establish the mitigation and testing plans for the West Farms Reservoirs mine . The mining operation will have minimal effect on the South Platte River in the form of minor groundwater depletions due to evaporation and water uses associated with mining. The depletions to the South Platte will be mitigated thru a temporary Substitute Water Supply Plan (as required and approved by the Division of Water Resources) to prevent injury to vested senior water rights . The reclamation plan proposes the creation of 4 slurry wall, lined reservoirs that will not be hydraulically connected to the Draft 4/24/2023 2:50 PM 28