A 'Method Based Survey' Succeeds in a Spanish Scrap Clearance Project - 15664
During the last years, a Waste Minimization Project has been implemented in Cofrentes NPP in a collaborative effort performed by IBERDROLA and ENRESA. The final result has been more than 760 t of metallic scrap including containerised materials but also massive surface contaminated objects have been managed and finally cleared. The initial project scope included 10 spent fuel pool racks weighting 130 tones but limited testing demonstrated they presented high contamination levels and were managed as radwaste including down-sizing and conditioning in ENRESA standard radwaste containers for metallic scrap (CMT's). This project started in 2008 and finished just in the summer of 2014. During these years planning and licensing, procurement, execution, including, a huge effort in decontamination and clearance measurement, was developed. The project closure is developing actually. The residual materials were stored and initially characterized previously its down-sizing and decontamination using chemical baths (warm diluted sulfuric acid and ultrasounds) , blasting (water jetting with iron grit) and in special cases mopping using industrial cleaners). Some big items were decontaminated previously its down-sizing. The materials were cleared using an approach similar to MARSAME approach based in MARSSIM guidelines. The 160 containers needed six in situ gamma spectrometry measurements each and 115 massive (from 0.45 t to 13.7 t) items need at least so many measurements as total surface in square meters. In total 763 t were cleared with only 0.6 t rejected and treated as radwaste. (authors)