Characterisation of Low Level Radioactive Waste from Cernavoda NPP G. Teodorov, A. Sandru, L. Toro MATE-FIN Ltd. Bucuresti Department of Radioactive Waste Management Solutions

 Outline ◦ Possible characterisation methods ◦ Waste streams ◦ WCAS – Waste Characterisation Assay System ◦ Waste Characterisation Process The 15 th National Conference of ICIT, Calimanesti 2009

Why characterisation?  Waste acceptance criteria Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

 Possible characterisation methods  Radionuclide content assessment based upon theoretical or analogue data;  Dose rate measurement and estimation using reference samples (assuming a known constant isotopic composition);  Easy to measure (ETM) - difficult to measure (DTM) radionuclides  Reference samples  measurement of certain “key nuclides” (ETM)  measurement of DTM radionuclides  Link ETM to DTM by scaling or correlation factors  Assessment of DTM nuclides from measurement of ETM nuclides by scaling factors Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

Waste streams to be significant for a given category of waste availability of complete and accurate reference data regarding the waste (e.g. dose rate, date of production, composition, etc) the activity of relevant radionuclide is high enough to be detected with acceptable uncertainity (above detection limits) The 15 th National Conference of ICIT, Calimanesti 2009

Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012 Tytpical CANDU waste streams Possible waste streams:22

The 15 th National Conference of ICIT, Calimanesti 2009 WCAS – Waste Characterisation Assay System Designed and commisioned by an international consortium (Quintessa, UK; Wert and Dekom, Slovakia; Josef Stefan Institute, Slovenia; MateFin, Romania) in 2005 Purpose: characterisation of the radioactive waste by direct measurements and scaling factors

Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012 Raw waste Segregation by source Segregation by material/activity Representative sampling Decomposition of sample Sample treatment Separate radio- nuclides of interest Source preparationMeasurement of Beta emitters Measurement of Alpha emitters Calculation of Correlation Coeffs. Gamma assay of indicator nuclides Application of Correlation Coeffs. Bulk Waste Charact -erised Waste RadiochemistryMeasurementComputer Codes Waste Inventor y Data

WCAS Gamma spectroscopy system intended to use for both portable (drum or package scanning) and laboratory (sample measurement) system Gross alpha and beta activity measurement system Liquid scintillation system for in nsitu and laboratory measurements Alpha spectroscopy system Complete radichemical laboratory Open digestor Distillation system Fume hoods, centrifuge, shaker, etc Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

Waste Characterisation Process Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

Waste Characterisation Process First step Charcaterisation of “old” waste Drum by drum measurement Uncertainity regarding the content Preparation for incineration Simple segregation solids - reactor and service bulding, compactable or uncompactable Liquid – different organic liquids Sample from each drum ETM, DTM, H3 measurement Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

H-3 nr.of samples average (Bq/kg) min (Bq/kg) max (Bq/kg) oil2103,45E+073,23E+032,2E+09 compactable solid1867,84E+071,08E+036,1E+09 activated carbon214,44E+062,42E+051,56E+07 ETM Co-60 (Bq/kg) Cs-137 (Bq/kg) Nb-94 (Bq/kg) Nb-95 (Bq/kg) Zr-95 (Bq/kg) Mn54 (Bq/kg) Sb-125 (Bq/kg) Sb-124 (Bq/kg) AG- 110M (Bq/kg) Cs-134 (Bq/kg) Gd-153 (Bq/kg) Cr-51 (Bq/kg) Fe-59 (Bq/kg) oil average (Bq/kg)5,99E+01 1,53E+ 01 1,85E+ 00 2,75E+ 00 2,98E+ 00 2,04E+ 00 6,99E+ 00 1,11E+ 00 1,00E+ 00 9,67E- 01 3,64E+ 01 6,33E+ 00 3,53E+ 00 min (Bq/kg)4,78E-01 9,09E- 01 4,30E- 01 7,44E- 01 5,73E- 01 3,47E- 01 1,25E+ 00 7,25E- 01 5,91E- 01 7,43E- 01 1,59E+ 01 1,85E+ 00 6,13E- 01 max (Bq/kg)2,00E+02 1,43E+ 02 7,65E+ 00 8,60E+ 00 1,06E+ 01 1,07E+ 01 9,24E+ 01 2,61E+ 00 2,18E+ 00 1,27E+ 00 1,40E+ 02 1,44E+ 01 1,55E+ 01 compactable solid average (Bq/kg)2,35E+04 4,26E+ 03 1,25E+ 03 1,09E+ 05 5,29E+ 04 5,88E+ 02 5,23E+ 03 6,66E+ 01 3,50E+ 01 1,94E+ 02 1,19E+ 03 3,65E+ 03 2,45E+ 02 min (Bq/kg)1,30E+01 5,66E+ 00 3,14E+ 00 6,74E+ 00 9,36E+ 00 2,15E+ 00 3,65E+ 00 1,74E+ 00 2,04E+ 00 2,95E+ 00 9,68E+ 00 2,10E+ 01 3,11E+ 00 max (Bq/kg)3,22E+05 6,47E+ 04 4,22E+ 04 3,55E+ 06 1,80E+ 06 1,27E+ 04 1,33E+ 05 1,33E+ 03 6,41E+ 02 1,91E+ 03 3,17E+ 04 1,17E+ 05 6,79E+ 03 activated carbon average (Bq/kg)2,49E+00 2,07E+ 01 1,52E+ 00 2,19E+ 00 3,33E+ 00 1,77E+ 00 5,54E+ 00 1,56E+ 00 1,41E+ 00 1,47E+ 00 5,87E+ 01 6,33E+ 00 3,53E+ 00 min (Bq/kg)1,98E+00 1,72E+ 00 5,65E- 01 1,35E+ 00 8,67E- 01 1,26E+ 00 3,05E+ 00 5,55E- 01 4,98E- 01 6,69E- 01 2,30E+ 01 1,85E+ 00 6,13E- 01 max (Bq/kg)2,89E+00 5,18E+ 01 2,30E+ 00 2,57E+ 00 4,57E+ 00 2,27E+ 00 7,32E+ 00 2,15E+ 00 2,25E+ 00 2,12E+ 00 9,64E+ 01 1,44E+ 01 1,55E+ 01 Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

Waste Characterisation Process Second step Difficulties to establich proper waste streams Samples from different part of the processes Crud samples from primary heat transfer Wipe samples Gamma spec for ETM nuclides DTM nuclides - in work Scaling factors – in work Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012

PORTFOLIO MATE-FIN in Cernavoda NPP: strongly involved, by firmly contracts, in: Processing and managing of some categories of radioactive wastes Maintenance of equipments and technical consulting for the managing of the radioactive wastes Main supplier of measurement and control equipments as well as for the continuous monitoring of the radioactivity into the plant. Workshop on Auditing and Verification of Radioactive Waste, 1-5 October 2012