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consisting of yellow-brown and gray to blue gray soft carbonaceous shale and clay interbedded <br /> with sandstone and shaley sandstone. At the base of the Laramie formation is the Fox Hills <br /> member, a cross-bedded gray to buff sandstone,which is slightly or well cemented. <br /> Surface and Groundwater <br /> Because of the low relief and deep, well-drained soils,there is virtually no surface runoff. No <br /> streams, springs, or seeps exist in the area. All water flows subsurface through aeolian deposits <br /> to Ennis Draw, a topographic swale (ephemeral drainage) located along the eastern boundary of <br /> the permit area. Ennis Draw appears to be a complex,braided, ancient stream bed that has been <br /> covered by windblown sand. The draw discharges several miles to the north into Box Elder <br /> Creek. <br /> Groundwater moves laterally toward the northeast, and apparently discharges into the sands and <br /> stream deposits in Ennis Draw. <br /> At the time the mine was originally permitted, groundwater in neither the coal nor overburden <br /> was known to provide a water supply for any purpose in the vicinity of the mine. Since that <br /> time, groundwater is being drawn for industrial uses at the mine, and several other wells have <br /> been drilled in the vicinity of the mine (per a review of State Engineer Records). However,no <br /> adverse impact from the mine has been observed or is expected, due to the geologic and <br /> hydrologic conditions of the site. <br /> Climate <br /> The mine site is situated in an area which has a"continental" type of climate, characterized by <br /> low relative humidity, a large amount of sunshine, light rainfall, moderately high winds, and <br /> large daily range in temperature. Average monthly temperatures are presented in the following <br /> table. The data are from Weather Trends (https://www.weathertrends360.com). These data are <br /> all within a couple degrees of data for Brighton, Colorado from the Western Regional Climate <br /> Center(wrccgdri.edu),which is affiliated with NOAA and a leading authority on Colorado <br /> weather and climate. (WRCC data does not include an extensive dataset for Keenesburg itself.) <br /> Average Monthly Temperature at Keenesburg, Colorado <br /> (All values in degrees Fahrenheit.) <br /> J F M A M J J A S O N D <br /> Average high 45 47 57 63 72 84 90 87 80 67 55 45 <br /> Average low 19 21 28 35 44 53 59 57 49 38 27 19 <br /> For the years 2008 through 2023, annual precipitation ranged from 8.31 to 21.88 inches with a <br /> mean of 14 inches (from National Weather Station data for nearby Brighton, Colorado). <br /> Vegetation, Wildlife and Land Use <br /> The undisturbed lands in the permit area are moderately to well stabilized by a sandsage-prairie <br /> sandreed plant association that is used primarily for grazing by cattle in summer months. <br /> Using the United State Fish and Wildlife Service's (USFWS) IPaC program available through <br /> the USFWS website,there are three endangered plant species that have the potential to be found <br /> Keenesburg Strip Mine Page 3 <br /> October 2024 Findings for PR-03 <br />