Table RD-16.  Activity Concentrations of Radionuclides Measured by Alpha Spectroscopy in Brantley Lake Sediment Samples Collected during 1998 – 2000 See CEMRC 2000 Report "Radiological and non-radiological constituents in surface water and sediments at selected reservoirs" for descriptions of locations and methods of data collection. Download pdf file Isotope Collection Date and Sampling Depth January 30, 1998 (12 m depth) January 30, 1998 (13 m depth) Activity Concentration (mBq g-1) aSD (mBq g-1) bMDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 6.93E-02 9.53E-03 1.40E-02 8.88E-02 1.00E-02 1.41E-02 238Pu <MDC   1.71E-02 <MDC   2.07E-02 239/240Pu 2.29E-01 1.80E-02 1.73E-02 2.65E-01 1.65E-02 1.29E-02 228Th 3.74E+01 9.72E-01 3.55E-01 4.64E+01 9.63E-01 2.76E-01 230Th 3.51E+01 9.33E-01 3.05E-01 5.67E+01 1.11E+00 2.93E-01 232Th 3.22E+01 8.84E-01 2.06E-01 4.48E+01 9.38E-01 1.35E-01 234U 6.74E+01 1.25E+00 2.07E-01 4.34E+01 9.51E-01 2.54E-01 235U 2.97E+00 2.71E-01 2.17E-01 2.45E+00 2.48E-01 2.12E-01 238U 4.26E+01 9.08E-01 1.94E-01 3.82E+01 8.74E-01 2.32E-01 Isotope February 4, 1998 (12 m depth) February 4, 1998 (13 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 7.96E-02 1.25E-02 2.24E-02 9.95E-02 1.05E-02 1.47E-02 238Pu <MDC   2.16E-02 <MDC   3.92E-02 239/240Pu 2.52E-01 1.94E-02 1.99E-02 2.76E-01 2.36E-02 2.19E-02 228Th 3.38E+01 9.10E-01 3.51E-01 4.44E+01 1.25E+00 5.36E-01 230Th 3.48E+01 9.23E-01 3.00E-01 5.70E+01 1.47E+00 6.14E-01 232Th 3.01E+01 8.44E-01 2.33E-01 4.20E+01 1.20E+00 4.37E-01 234U 5.08E+01 1.04E+00 1.91E-01 4.73E+01 9.38E-01 1.53E-01 235U 2.33E+00 2.39E-01 2.67E-01 2.20E+00 2.19E-01 1.89E-01 238U 3.64E+01 8.31E-01 1.99E-01 3.85E+01 8.17E-01 1.80E-01 Isotope October 7, 1998 (11 m depth) October 7, 1998 (12 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 8.02E-02 9.48E-03 1.18E-02 7.95E-02 1.07E-02 1.52E-02 238Pu 2.16E-02 6.17E-03 1.69E-02 <MDC   1.83E-02 239/240Pu 2.87E-01 1.82E-02 1.88E-02 2.34E-01 1.62E-02 1.34E-02 228Th 3.77E+01 1.11E+00 4.04E-01 3.69E+01 1.17E+00 4.00E-01 230Th 3.57E+01 1.07E+00 3.99E-01 3.72E+01 1.18E+00 4.49E-01 232Th 3.16E+01 1.00E+00 2.35E-01 3.20E+01 1.08E+00 3.87E-01 234U 6.82E+01 1.41E+00 2.29E-01 6.30E+01 1.39E+00 2.98E-01 235U 2.76E+00 2.82E-01 2.35E-01 2.49E+00 2.75E-01 2.62E-01 238U 4.55E+01 1.06E+00 2.06E-01 4.27E+01 1.06E+00 2.87E-01 Isotope October 7, 1998 (14 m depth) October 7, 1998 (14 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 8.51E-02 9.69E-03 1.27E-02 8.08E-02 9.85E-03 1.40E-02 238Pu <MDC   2.29E-02 <MDC   1.77E-02 239/240Pu 2.06E-01 1.34E-02 1.40E-02 2.32E-01 1.56E-02 1.73E-02 228Th 3.91E+01 1.19E+00 6.57E-01 4.14E+01 1.33E+00 6.80E-01 230Th 4.60E+01 1.32E+00 6.30E-01 3.93E+01 1.30E+00 7.55E-01 232Th 3.84E+01 1.17E+00 4.14E-01 3.51E+01 1.20E+00 6.54E-01 234U 4.84E+01 1.16E+00 1.81E-01 5.83E+01 1.24E+00 1.75E-01 235U 2.95E+00 3.05E-01 2.51E-01 2.25E+00 2.48E-01 2.17E-01 238U 4.01E+01 1.02E+00 2.15E-01 4.18E+01 9.88E-01 2.04E-01 Isotope July 1, 1999 (11 m depth) July 1, 1999 (9 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 9.53E-02 9.48E-03 1.15E-02 1.26E-01 1.21E-02 1.41E-02 238Pu <MDC   2.31E-02 <MDC   2.14E-02 239/240Pu 2.38E-01 1.70E-02 1.34E-02 3.23E-01 1.83E-02 9.85E-03 228Th 3.45E+01 1.10E+00 4.29E-01 3.40E+01 9.76E-01 3.91E-01 230Th 3.46E+01 1.10E+00 3.78E-01 3.47E+01 9.86E-01 3.23E-01 232Th 3.03E+01 1.02E+00 3.17E-01 3.23E+01 9.44E-01 2.71E-01 234U 6.00E+01 1.08E+00 1.48E-01 6.61E+01 1.24E+00 1.79E-01 235U 2.21E+00 2.16E-01 1.82E-01 2.58E+00 2.49E-01 1.78E-01 238U 4.12E+01 8.35E-01 1.74E-01 4.27E+01 9.13E-01 1.91E-01 Isotope July 9, 1999 (14 m depth) July 9, 1999 (13 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 7.49E-02 9.30E-03 1.34E-02 9.98E-02 1.00E-02 1.19E-02 238Pu 1.31E-02 3.97E-03 1.07E-02 2.44E-02 6.37E-03 1.69E-02 239/240Pu 2.60E-01 1.37E-02 8.79E-03 2.42E-01 1.63E-02 1.59E-02 228Th 4.19E+01 1.30E+00 6.37E-01 3.89E+01 1.54E+00 1.10E+00 230Th 3.78E+01 1.22E+00 4.07E-01 3.63E+01 1.46E+00 8.36E-01 232Th 3.43E+01 1.16E+00 3.25E-01 3.74E+01 1.48E+00 7.70E-01 234U 5.18E+01 1.03E+00 1.94E-01 5.98E+01 1.15E+00 1.79E-01 235U 2.59E+00 2.48E-01 1.79E-01 2.84E+00 2.65E-01 1.74E-01 238U 3.73E+01 8.25E-01 1.62E-01 4.08E+01 8.87E-01 1.81E-01 Isotope June 8, 2000 (12 m depth) May 31, 2000 (13 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 8.29E-02 1.15E-02 2.10E-02 7.10E-02 1.11E-02 2.33E-02 238Pu <MDC   1.56E-02 <MDC   1.33E-02 239/240Pu 2.07E-01 1.48E-02 1.44E-02 1.79E-01 1.30E-02 1.17E-02 228Th 3.86E+01 9.08E-01 3.56E-01 3.80E+01 1.15E+00 5.55E-01 230Th 3.53E+01 8.55E-01 2.64E-01 3.31E+01 1.06E+00 4.05E-01 232Th 3.33E+01 8.23E-01 2.08E-01 3.23E+01 1.04E+00 3.73E-01 234U 5.38E+01 1.64E+00 2.82E-01 5.02E+01 1.29E+00 2.65E-01 235U 2.33E+00 3.37E-01 3.90E-01 2.60E+00 3.04E-01 2.75E-01 238U 3.80E+01 1.30E+00 2.92E-01 3.78E+01 1.07E+00 2.39E-01 Isotope June 8, 2000 (12 m depth) June 8, 2000 (12 m depth) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) Activity Concentration (mBq g-1) SD (mBq g-1) MDC (mBq g-1) 241Am 3.94E-02 1.23E-02 3.12E-02 8.29E-02 1.31E-02 1.99E-02 238Pu <MDC   2.21E-02 <MDC   1.93E-02 239/240Pu 1.97E-01 1.47E-02 1.23E-02 2.06E-01 1.50E-02 1.40E-02 228Th 3.69E+01 8.37E-01 2.27E-01 4.15E+01 1.20E+00 5.34E-01 230Th 3.37E+01 7.93E-01 3.20E-01 3.53E+01 1.09E+00 3.89E-01 232Th 3.27E+01 7.71E-01 2.26E-01 3.67E+01 1.11E+00 3.68E-01 234U 4.72E+01 1.30E+00 2.65E-01 4.79E+01 1.28E+00 2.63E-01 235U 2.00E+00 2.70E-01 2.80E-01 3.25E+00 3.50E-01 2.80E-01 238U 3.60E+01 1.08E+00 3.18E-01 3.60E+01 1.05E+00 2.47E-01 aSD=One standard deviation of the radioanalytical uncertainty bMDC=Minimum Detectable Concentration