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because the present water levels have not recovered to the land surface in any of the draws intersected <br />by these pits. The water levels in these pits have been steadily increasing since the spoil monitoring <br />wells (GD-3 and GF-11) were installed. Generalized calculations accounting for pit areas and assuming <br />annual infiltration (2.5 inches/yr), underburden inflows approximately equivalent to infiltration volumes, <br />and estimated groundwater discharge into the QR aquifer downgradient from the pits, suggest that spoil <br />springs will eventually form in the D pit area but are less likely to form in the E pit area . <br />Recharge to the Third White Sandstone aquifer in the vicinity of Flume Gulch will be less during mining <br />and for a few years after mining as the backfill aquifer recovers. The majority of the recharge to the <br />backfill aquifer will go into backfill aquifer storage initially and, therefore, will decrease the recharge to the <br />Third White Sandstone aquifer. Spoil springs are not anticipated to develop in the Flume Gulch drainage. <br />Rather, most if not all of the recharge to A East and G pits will be discharged into the Third White <br />Sandstone through the low-wall face of A East pit. <br />An increase in groundwater discharge to the surface associated with the development of spoil springs is <br />anticipated. These discharges will act to regulate the hydrostatic heads in the northern ends of the <br />backfill aquifers and cause them to remain fairly stable. Therefore the groundwater influx to down-dip <br />aquifers should remain fairly steady. In areas where saturated and confined conditions prevailed prior to <br />mining, this influx is expected to be slightly less than the influx existing under pre-mine conditions due to <br />the unconfined nature of the backfill aquifers in the vicinity of the backfill/undisturbed strata contact. <br />Seasonal changes are likely to cause some fluctuations in the influx rates. <br />Flow from Springs: <br />More springs are expected to develop during post-mine conditions (spoil springs) than existed during pre- <br />mine conditions due to the higher transmitting ability of the backfill spoils that will allow the groundwater to <br />flow more readily to the north end of the mined areas. The total quantity of groundwater discharged to <br />the spoil springs is expected to be larger during the post-mining period. Based on the results of backfill <br />aquifer monitoring these springs are anticipated to provide water with quality suitable for use by wildlife <br />and livestock. The Johnson Gulch Spring is an example of a spoil spring developing at the northern end <br />of a mined area. This spring emanates near the contact between the backfilled spoils in A pit and the <br />undisturbed strata downgradient from the pit. <br />Cottonwood Spring is an example of a natural spring, which probably has not been influenced by the spoil <br />aquifer even though it is located close to the northern margin of the D pit mined area. The source of <br />4-238a <br />PRy <br />a let loa