Ralston Reservoir

The smallest concentrations of suspended 226r3 and U were found in samples collected from the inlet and outlet of Ralston Reservoir. Previous 226r3 concentrations in the suspended material for samples collected at different locations in Ralston Reservoir by Lammering (2) were in the range of 2.1 to 12 pCi/g. 

Lammering, M. "Impact of Schwartzwalder Mine on the Water Quality of Ralston Creek, Ralston Reservoir, and Upper Long Lake", Technical Investigation Branch, Surveillance and Analysis Division, U.S. Environmental Protection Agency, Region VIII, SA/TIB-25, 1973, 16 p. 

Releases of Radium and Uranium into Ralston Creek and Reservoir, Colorado, from Uranium Mining... 

Sixteen 20-L water samples containing suspended material, and 14 samples of bed sediments were collected from different sites in Ralston Creek and Reservoir during the winter of 1980 and the spring of 1981. The study area and sampling sites are shown in Figure 1. The stream was shallow, 1 to 3 ft deep,... 

Figure 1. Map of Ralston Creek and Reservoir, near Golden, Colorado.

Creek Water. Concentrations of dissolved 226r3 an(j u -jn Ralston Creek and Reservoir water are plotted in figure 3. These data indicated that the 226r8 concentration in creek water 400 ft upstream from the mine (background concentration) was 0.13 pCi/L, and the U concentration in the same water was 4.0 pg/L. 

Suspended Material. The material retained by the 0.45-pm membrane filters during filtration of the water samples collected from Ralston Creek and Reservoir was classified as suspended solids concentrations are shown in figure 4. The 226r3 content of suspended sediment in the mine effluent was 1,300 pCi/g U content of suspended sediment was 2,400 pg/g. Suspended-material load for this sample was 6 mg/L during the sample collection. Total release of both radionuclides (dissolved and suspended) was then calculated to be 8.4 pCi/L for 226r3 and 1,710 pg/L for U. Assuming an average daily... 

Yang IC, Edwards KW. 1984. Releases of radium and uranium into Ralston Creek and Reservoir Colorado USA from uranium mining. In Barney GS, Navratil JD, Schulz W, eds. 185th meeting American Chemical Society Symposium Series 246. Geochemical behavior of disposed radioactive waste, Seattle WA, March 20-25, 1983. Washington, DC American Chemical Society, 271-286. 

Crocker, H.S. (1935). Ralston Creek Reservoir Site Irrigation Division No. 1, Water Districts No. 6 and 7. Moffat Tunnel Extension Project, Municipal Water Works Denver CO. http //www.worldcat.org/title/presentation-at-moffat-filter-plant/oclc/48017835 referer=brief resultsP... 

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