Decontamination of the case of main pump in the primary circuit of WWER type reactors by an electrochemical procedure

A remote controlled equipment for electrochemical decontamination of pump case using movable cathode was developed. The decontamination factors of the six plant decontaminations were 10-500. The dark oxide layer could be removed effectively from the stainless steel surfaces, therefore the weldings could be checked. The liquid waste owing to the procedure was low. The decontamination process required one shift, and the collective dose for the staff was 2-3 mSv. (author)