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Shallow groundwater flows east to west across site. Temporal and spatial fluctuation in the water <br />table corresponded with irrigation water inputs. Groundwater head gradients are developed in <br />irrigated pastureland located on an elevated terrace 10 to 12 ft higher than wetland areas to the west. <br />Well hydrographs show how the pulse of artificial groundwater recharge from imgation moves west <br />towards the river. Wells located east of the terrace show rapid decreases in water levels whereas <br />wells further west show more gradual water level decreases and retained water for longer periods. <br />These wells in the west reflect longer travel times as the pulse ofgroundwater recharge via irrigation <br />inputs moves through shallow groundwater flow system. <br />Spring discharge provide minor inputs to overall site wetland water budget. Spring flow provides <br />wet meadow conditions and groundwater recharge in localized areas but not enough to support large <br />wetland areas as functioning discharge systems. Groundwater in hydraulic connection with Colorado <br />River water was observed in well 5E-20, located approximately 750 ft south ofthe river. This well <br />was the only well not to go dry during the monitoring period showing an average static depth to <br />groundwater at 3.6 ft bgs April through June 1999. <br />Jurisdictional wetland acreage decreased markedly at the site as a result of irrigation cessation and <br />documentation via hydrogeologic techniques. Jurisdictional wetland boundaries at proposed <br />crossings in the vicinity of Monument Creek did not change and remain as originally designated. <br />6 <br />