3.7 hazardous materials and hazardous waste - Missile Defense ...

Chapter 3—Affected EnvironmentSurface WaterThe Missile Site Radar complex ROI is in the Devils Lake, Pembina, andPark watersheds, USGS Cataloging Units 09020201, 09020313, and09020310 (U.S. EPA, 1998—Surf Your Watershed). There are nosignificant rivers or bodies of surface water in the ROI. The ROI isaffected by the soils' ability to hold water (soils are clay and silt, lowpermeability). The Missile Site Radar is not within a 100-year floodplain(Greenwood, 1998—Electronic communication, June 5.)Due to the slow infiltration rate, heavy rains often result in surface waterbeing retained in depressions. The only natural surface water body onthe site is a small intermittent stream, Roaring Nancy Creek, that crossesthe western side of the site. This creek has been classified as a wetlandby the Corps of Engineers. Storm water at the site flows through twodrainage swales into the creek, and is carried northwest to a pondapproximately 8 kilometers (5 miles) away (U.S. Army Center for HealthPromotion and Preventive Medicine, 1995—Final Report, Site Inspection,SRMSC). Additionally, water from the site's sewage lagoons areperiodically lowered by discharging to Roaring Nancy Creek when thelagoons fill from heavy rains. This discharge is regulated under anNPDES permit issued by the state of North Dakota. The permit requiresperiodic monitoring of surface water runoff.GroundwaterGroundwater in the Missile Site Radar area is found in the Pierre Aquifer,which consists of fractured light to dark gray shale. Groundwater in theaquifer ranges in depth from 5 to 8 meters (15 to 25 feet) with pumprates ranging from 20 to 1,130 liters (5 to 300 gallons) per minute.Recharge for the Pierre Aquifer occurs through precipitation, snowmelt,and infiltration from prairie potholes (seasonal water bodies). The PierreAquifer is not a major groundwater source in the region.The Missile Site Radar did receive its potable water from the municipalFordville Well Field, in the south-central part of Walsh County. However,in 1996 the Missile Site Radar was connected to the town of Langdon’swater supply, a surface water source northeast of Langdon (U.S. ArmyCenter for Health Promotion and Preventive Medicine, 1995—FinalReport, Site Inspection, SRMSC). The Missile Site Radar is stillconnected to the Fordville Well Field and occasionally uses the water fornon-potable uses. Pump rates for the Fordville Well Field are up to 1,136liters (300 gallons) per minute. Cavalier AFS, east of the Missile SiteRadar, withdrew approximately 185,022 cubic meters (150-acre feet) peryear before changing water supplies. In addition, other users in theregion are withdrawing another 740,089 cubic meters (600-acre feet)from the Fordville Aquifer. No noticeable yield decline trends or changesNMD Deployment Final EIS 3-415