UMTRA project water sampling and analysis plan, Old and New Rifle, Colorado
Surface remedial action at the Rifle, Colorado, Uranium Mill Tailings Remedial Action (UMTRA) Project site began in the spring of 1992. Results of water sampling at the Old and New Rifle processing sites for recent years indicate that ground water contamination occurs in the shallow unconfined alluvial aquifer (the uppermost aquifer) and less extensively in the underlying Wasatch Formation. Uranium and sulfate continue to exceed background ground water concentrations and/or maximum concentration limits at and downgradient from the former processing sites. These constituents provide the best indication of changes in contaminant distribution. Contamination in the uppermost (alluvial) aquifer at New Rifle extends a minimum of approximately 5000 feet (ft) (1,524 meters [m]) downgradient. At Old Rifle, the extent of contamination in the alluvial aquifer is much less (a minimum of approximately 1,000 ft [305 m]), partially due to differences in hydrologic regime. For example, the Old Rifle site lies in a relatively narrow alluvial floodplain; the New Rifle site lies in a broad floodplain. Data gathering for the Rifle baseline risk assessment is under way. The purpose of this effort is to determine with greater precision the background ground water quality and extent of ground water contamination at the processing sites. Historical surface water quality indicates that the Colorado River has not been affected by uranium processing activities. No compliance monitoring of the Estes Gulch disposal cell has been proposed, because ground water in the underlying Wasatch Formation is limited use (Class 111) ground water and because the disposal cell is hydrogeologically isolated from the uppermost aquifer.
- Research Organization:
- Jacobs Engineering Group, Inc., Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-91AL62350
- OSTI ID:
- 10181492
- Report Number(s):
- DOE/AL/62350--141; ON: DE94018481
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
54 ENVIRONMENTAL SCIENCES
540230
540250
GEOCHEMISTRY
GROUND WATER
MILL TAILINGS
MONITORING
RADIOACTIVE EFFLUENTS
RADIOACTIVE MATERIALS MONITORING AND TRANSPORT
REMEDIAL ACTION
RISK ASSESSMENT
SITE CHARACTERIZATION
SITE RESOURCE AND USE STUDIES
URANIUM
WATER QUALITY