Abstract:
The main reason for conducting a corrosion surveillance or corrosion monitoring program (CMP) at a RR facility or at a spent fuel wet-storage facility is to evaluate the effect of the prevailing water parameters at either facility on the corrosion of the spent fuel cladding and/or of other structural materials. A program of this nature gives an insight into the extent of corrosion of the metallic materials. It is well known that good quality water is essential to prevent corrosion in a spent fuel basin. However, certain water parameters like conductivity, chloride ion content and some other ions, in quantities well below levels of concern, have a synergistic effect on the pitting corrosion behavior of aluminium alloys. Hence, maintenance of water parameters within specified limits is not reason enough for complacency about corrosion of fuel cladding. A well-planned and executed CMP would give the RR or spent fuel basin manager an insight into the state of fuel cladding and/or metallic structural materials in terms of corrosion. A CMP involves the exposure of test coupons to the RR or basin water for a pre-determined period followed by its evaluation to detect for corrosion.