Significance of water fluxes in a deep arid-region vadose zone to waste disposal strategies

Conference · Mon Feb 28 23:00:00 EST 1994

OSTI ID:10128935

Johnejack, K R; Blout, D O; Sully, M J; Emer, D F; Hammermeister, D P ^[1]; Dever, L G; O`Neill, L J ^[2]; Tyler, S W ^[3]; Chapman, J ^[4]

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1. Reynolds Electrical and Engineering Co., Inc., Las Vegas, NV (United States)
2. DOE Nevada Operations Office, Las Vegas, NV (United States). Waste Management Div.
3. Desert Research Institute, Reno, NV (United States). Water Resources Center
4. Desert Research Institute, Las Vegas, NV (United States). Water Resources Center

Recently collected subsurface site characterization data have led to the development of a conceptual model of water movement beneath the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada Test Site (NTS) that differs significantly from the conceptual model of water movement inherent in Resource Conservation and Recovery Act (RCRA) regulations. At the Area 5 RWMS, water fluxes in approximately the upper 75 m (250 ft) of the vadose zone point in the upward direction (rather than downward) which effectively isolates this region from the deep (approximately 250 m (820 ft)) uppermost aquifer. Standard RCRA approaches for detection and containment (groundwater monitoring and double liners/leachate collection/leak detection systems) are not able to fulfill their intended function in this rather unique hydrogeologic environment. In order to better fulfill the waste detection and containment intentions of RCRA for mixed waste disposal at the Area 5 RWMS, the Department of Energy, Nevada Operations Office (DOE/NV) is preparing a single petition for both a waiver from groundwater monitoring and an exemption from double liners with leachate collection/leak detection. DOE/NV proposes in this petition that the containment function of liners and leachate collection is better accomplished by the natural hydrogeologic processes operating in the upper vadose zone; and the detection function of groundwater monitoring and the leak detection system in liners is better fulfilled by an alternative vadose zone monitoring system. In addition, an alternative point of compliance is proposed that will aid in early detection, as well as limit the extent of potential contamination before detection. Finally, special cell design features and operation practices will be implemented to limit leachate formation, especially while the cell is open to the atmosphere during waste emplacement.

• Research Organization: Reynolds Electrical and Engineering Co., Inc., Las Vegas, NV (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC08-94NV11432
• OSTI ID: 10128935
• Report Number(s): CONF-940225--41; ON: DE94007389; BR: 400700000
• Country of Publication: United States
• Language: English

Related Subjects

052002
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
54 ENVIRONMENTAL SCIENCES
540230
540250
ARID LANDS
CONTAINMENT
GEOLOGY
GROUND DISPOSAL
GROUND WATER
HAZARDOUS MATERIALS
HYDROLOGY
LEACHATES
LEAKS
LINERS
LOW-LEVEL RADIOACTIVE WASTES
MONITORING
NEVADA TEST SITE
RADIOACTIVE MATERIALS MONITORING AND TRANSPORT
RADIOACTIVE WASTES
REGULATIONS
SITE RESOURCE AND USE STUDIES
WASTE DISPOSAL AND STORAGE