Evaluation of reduced silver content relative to the activation products in remaining R- and P-reactor structures

Abstract

An analytic model and calculational methodology have been established previously to quantify the radioisotopes present in the Savannah River Site (SRS) P-reactor and R-reactor tanks and in the structural materials surrounding those tanks. These radioisotopes are the result of neutron activation of the materials during reactor operation. The analysis results were based upon a specific set of input assumptions for the elemental composition of the materials of construction. Based upon the results of that analysis, efforts to more accurately quantify the silver content in the stainless steel used in the fabrication of the reactor vessel have been completed. Laboratory testing of vintage stainless steel from stainless piping extracted from R-reactor indicates a maximum silver content that is nearly an order of magnitude lower than that assumed in the previous calculation. Based on the new silver content information simulations were completed to evaluate the impact of the reduced silver content.

Evaluation of reduced silver content relative to the activation products in remaining R- and P-reactor structures

“…An analysis has been completed to evaluate the effect of silver content in stainless steel relative to the analysis of R-and P-reactor radioisotopic inventory reported previously. 1 Those calculations use a value of 75 ppm for the silver content of the stainless steel. That value for silver content is now believed to be considerably higher than the actual silver content of the stainless steel of construction.…”

“…% in silver. It is deduced that the value of 75 ppm assumed in the original R-and P-reactor analysis document 1 was derived from averaging the values provided in Reference 2 for the four R-tank specimens.…”