Perspectives on USNRC Study Request Nuclear & Radiation Studies Board April 26, 2010 Ralph Andersen, CHP Senior Director – Radiation Safety & Environmental Protection

Health Physics Society Perspective  Premise: – Epidemiological studies alone will not provide definitive results at low doses and low dose rates  Recommendations: – Do not fund studies with low statistical power – Do not fund studies for which there is insufficient data to properly control for confounding factors  Although such studies do not add scientific knowledge – they may be useful in addressing allegations and concerns about health effects

BEIR VII Committee Perspective “In general, additional ecological studies of persons exposed to low levels of radiation from environmental sources are not recommended.” -BEIR VII Phase 2 Report (2006)

Challenges with Descriptive (Ecological) Studies  Lack of specific information on individuals within a population (e.g., dose estimates)  Difficulty in adequately addressing confounding factors  Variability in data accuracy and completeness  Population migration or movement  Low statistical power

Populations Living Around Nuclear Power Plants (2000 Census Data) Distance  Total – 0-2 miles – 0-5 miles – 0-10 miles  Range (individual plants) – 0-2 miles – 0-5 miles – 0-10 miles Population – 65,239 – 588,667 – 2,795,411 – 0 – 7,694 – 2 – 67,154 – 1,882 – 201,321

NPP Programs for Monitoring and Controlling Public Dose  Radiological Effluent Monitoring & Control – Radioactivity in Gaseous & Liquid Effluents – Direct Radiation Exposure – Doses to maximally exposed people (infant, child, teen or adult)  Radiological Environmental Monitoring – Monitoring results for all principal exposure pathways  Land Use Census – Determine maximally exposed people

Typical Estimated Maximum Doses to People Living Around NPPs (2000) Dose Type  Gaseous Effluents – Total Body – Organ  Liquid Effluents – Total Body – -Organ Annual Dose (mrem)  ALARA Criteria = 10 – 0.2 – 0.5  ALARA Criteria = 3 – 0.1 – 0.07

NRC Public Dose Criteria for ALARA Summary of Appendix I Design Objectives and Dose Criteria Type of Effluent Pathway Organ Dose Limit (per yr per unit) Liquid All total body 3 mrem (0.03 mSv) All any organ 10 mrem (0.1 mSv) Gaseous All total body 5 mrem (0.05 mSv) All skin 15 mrem (0.15 mSv) Radioiodines All any organ 15 mrem (0.15 mSv) Particulates All any organ 15 mrem (0.15 mSv) Gaseous gamma air dose n/a 10 mrad (0.10 mGy)* Beta air dose n/a 20 mrad (0.20 mGy)* Note: * Air doses are expressed in mrad.

Recommendations  Assess impact of variability in populations  Assess validity and uncertainty in dose estimate data  Review published literature with regard to validity, limitations and insights  Identify and explain limitations up front  Avoid slicing and dicing of the data