Links
- Document: Report
- Download citation as: RIS | Dublin Core
Abstract
Previous chemical, geological, and hydrological information describing the physical and chemical environment of the Nevada Test Site (a Federal reserve for the testing of nuclear explosive devices) has been combined with new radiochemical and isotope data for water and rock samples in order to explain the behavior of uranium during alteration of thick sequences of rhyolitic volcanic rocks and associated volcaniclastic sediments. A model is proposed in which uranium mobility is controlled by two competing processes. Uranium is liberated from the volcanic rocks through dissolution of the glassy constituents and is carried in solution as a uranyl carbonate complex. Uranium is subsequently removed from solution by adsorption on secondary oxides of iron, titanium, and manganese, as observed in fission-track maps of aquifer rocks. The model explains the poor correlation of dissolved uranium with depth within tuffaceous sequences in which percolation of ground water is predominantly downward. Good positive correlation of dissolved uranium with dissolved Na, total dissolved solids, and total carbonate supports the glass dissolution model, while inverse correlation of dissolved uranium with U234/U238 ratios of waters implies uranium is being absorbed by a relatively insoluble, surficial phase. Alpha radioactivity of Test Site water is primarily caused by high U234 contents, and beta activity is highly correlated with dissolved K (K40). Small amounts of dissolved radium, Pb210, and Po210 are present but no evidence was found for alpha activity sources related to nuclear testing (Pu, U235 ). A filtered but unacidified carbonate solution of uranium was found to be stable (± 10 percent of original U concentration) for years when stored in acid-washed polyethylene bottles.
Study Area
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Uranium in waters and aquifer rocks at the Nevada Test Site, Nye County, Nevada |
| Series title | Journal of Research of the U.S. Geological Survey |
| Volume | 6 |
| Issue | 4 |
| Year Published | 1978 |
| Language | English |
| Publisher | U.S. Geological Survey |
| Contributing office(s) | Central Energy Resources Science Center |
| Description | 10 p. |
| First page | 489 |
| Last page | 498 |
| Country | United States |
| State | Nevada |
| County | Nye County |
| Other Geospatial | Nevada Test Site |
| Google Analytic Metrics | Metrics page |