Decontamination of Point Beach-1 and Surry-2 Steam Generator Tubesheet Sections

摘要

A full thickness tubesheet section containing thirteen tubes and two empty tube holes from a retired Point Beach-1 Nuclear Station Steam Generator was decontami¬nated by a combination of strong acids, weak acids, alkaline cleaning, electro cleaning and mechanical cleaning and sectioned by milling for subsequent exami¬nation by other contractors. A full thickness section of tubesheet from a retired Surry-2 steam generator containing four tubes was also decontaminated and sectioned by techniques similar to those used for the Point Beach assembly.nDeposits and surfaces of the two empty holes in the Point Beach tubesheet were examined and the deposits were found to consist primarily of metal, and metal oxides (mainly iron). There were significant quantities of phosphorus and calcium compounds along with smaller amounts of sodium, sulfur and chloride compounds in the deposits.