14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Nuclear Power Sister Plant Radiological Effluent Release Comparisons J.T. Harris 1,3, D.W. Miller 2,3 1 Purdue University, West Lafayette, IN; 2 University of Illinois at Urbana-Champaign, Urbana, IL; 3 North American Technical Center, Urbana, IL

14th Annual RETS/REMP Workshop June 28-30, 2004 Outline  Introduction  NATC U.S. Effluent Database  Effluent Release Trends  Dose Determination  U.S. Commercial NPP Benchmarking  Conclusions

14th Annual RETS/REMP Workshop June 28-30, 2004 Introduction  Effluent Tracking –Liquid and gaseous effluents –BNL Collected and tabulated US NPP effluent data prior to 1994 –1996 NATC asked to take over task (as independent scientific organization for UNSCEAR) –Since 1998, NATC has collected and performed research on effluent data from NRC and licensees (support of UNSCEAR, EPRI, NEI, ANI, licensees and universities)

14th Annual RETS/REMP Workshop June 28-30, 2004 Introduction  NATC U.S. Effluent Database –In 2000, NATC program became known as the Public Radiation Safety Program –Goals include:  development and maintenance of database for use by NPPs, regulatory bodies and scientific analysis  Expanded trend analysis and discussion of effluent data  Standardized entry form development for licensee use  Establishment of effluent website for general use  Establishment of an effluent expert group  (Expanded to radwaste)

14th Annual RETS/REMP Workshop June 28-30, 2004 Introduction  Data Compilation and Purpose –Current (Ongoing) Study  Evaluate significance, if any, of NPP effluent releases in terms of trends, dose commitments and benchmarking (emphasis on sister plant comparisons)  Analysis of data from (2003 in progress)

14th Annual RETS/REMP Workshop June 28-30, 2004 NATC U.S. Effluent Database  Developed to satisfy needs of U.S. and international organizations –Format – U.S. NRC Reg. Guide 1.21 reports and UNSCEAR –Raw and un-normalized values (Ci and GBq) for individual units and sites (operating and shutdown) –Normalized values (activity vs. net electrical energy, not the best) –Collective effective dose calculated (UNSCEAR)

14th Annual RETS/REMP Workshop June 28-30, 2004 Effluent Release Trends  Important to evaluate release trends, especially as nuclear power generation steadily increases in the U.S.  Trends evaluated for un-normalized and normalized data (better reflect particular operating conditions and no skewed values, but public doesn’t care)

14th Annual RETS/REMP Workshop June 28-30, 2004 Effluent Release Trends  8-year period fairly constant, with slight decreases in some categories

14th Annual RETS/REMP Workshop June 28-30, 2004 Effluent Release Trends  8-year period fairly constant, with slight decreases in some categories

14th Annual RETS/REMP Workshop June 28-30, 2004 Dose Determination  Dose determination performed to evaluate the human effects of effluents  Currently NATC uses UNSCEAR effluent dose assessment model (for average trends) –Uses “representative” environmental conditions and population density –Collective effective dose per unit of electrical energy generated (normalized release divided by calculated collective doses per unit release – from dose pathway models)

14th Annual RETS/REMP Workshop June 28-30, 2004 Dose Determination  Total BWR and PWR effluent collective effective doses (very low – highest value 0.12% annual limit)

14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Commercial NPP Benchmarking  Commercial nuclear power industry has long used benchmarking studies to promote excellence in plant work management and operation practices  Other organizations also benchmark (U.S. NRC, ANI, INPO, and NATC)  Reductions in plant RETS-REMP programs have led to concern among U.S. NRC and ANI- thus it is even more important now to further monitor and compare effluent releases  Performance ranks lead to increased scrutiny

14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Commercial NPP Benchmarking  Current study – ranking/comparing releases by plant design (sister plants)- un-normalized data (within and between groups)  BWR sister plants –GE: BWR-2, BWR-3, BWR-4, BWR-5, BWR-6  PWR sister plants –B&W 2 Loop, CE 2 Loop, Westinghouse 2 Loop, 3 Loop (Gen 1 & 2), 3-Loop (Gen 1) and 4 Loop (Gen 1 & 2)

14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Commercial NPP Benchmarking  BWR Results Average Effluent Release Average Collective Effective Doses

14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Commercial NPP Benchmarking  PWR Results Average Effluent Release Average Collective Effective Doses

14th Annual RETS/REMP Workshop June 28-30, 2004 U.S. Commercial NPP Benchmarking  Results –BWR  Effluent release values very wide ranging  No obvious trends  Age affect (newer plants, higher liquids; older plants, higher gaseous) –PWR  Wide ranging but more consistent with each other (compared to BWR designs)  No affect from age –U.S. NPP effluent data never presented this way

14th Annual RETS/REMP Workshop June 28-30, 2004 Conclusions  Development of U.S. Effluent database has been used to provide data to utilities, UNSCEAR, U.S. NRC and CEPN (European Technical Center)  Calculated “average” CEDs give indication of how low effluent releases are and can be used for international comparisons  Sister plant breakdowns give additional tool for utilities and new perspective for comparison  However, more studies need to be performed to truly grasp effluent releases, as releases are not dictated solely by electrical generation –Other studies underway - complete inventory of radioactive materials solid radwaste), work practices, individual isotopes, radwaste systems –Use of standardized report and expert group –More discussion through RETS-REMP workshop –Discussion with UNSCEAR  Effluent data important for future (baseline data for new siting, radionuclide buildup in the environment and public perception)

14th Annual RETS/REMP Workshop June 28-30, 2004 Thank you!! Questions?