Cook Plant preoperational studies 1970 / John C. Ayers ... [et al.].

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tains the activities of each of the radionuclides present in the sample spectrum.
The graph of the field spectrum is used to detect the presence of radioisotopes
for which the NASA program was not looking.
The data sheet includes two error values for each field spectrum analyzed.
The chi square value is a measure of how well the entire calculated spectrum
matched the field spectrum. The amount of each radionuclide predicted to be in
the field spectrum has associated with it a standard deviation expressed as a
percent of the predicted activity. The two error values together with the graph
of the field spectrum are used to decide the validity of the predicted activities
for the given field spectrum.
Field work around the Big Rock Point Nuclear Power Plant has established
a minimum detectable activity for cesium-137 of 0.02 microcuries per square meter.
Minimum detectable activities for other radionuclides will vary depending on
gamma ray energies and abundances.
APPLICATIONS
Measurements of radionuclides present in bottom sediment near the
Palisades and the Donald C. Cook Nuclear Power Plants were made with the underwater gamma probe during the Fall of 1970. Both plants are located on the shore
of Lake Michigan near Benton Harbor, Michigan. The Palisades Plant is scheduled
to become operational during 1971, and the Cook Plant is still under construction.
Thus, both surveys provided preoperational data for future reference.
Four passes were made at each plant with the underwater probe. The passes
ran parallel to the shoreline from four miles north to four miles south of each
plant. The passes were made at distances of 3/8, 3/4, 1 1/2, and 3 miles from
shore. Figure 4 shows the ship's course during the survey of the Donald C.
Cook Plant.