Fukushima Emergency Planning Zones, Use of Potassium Iodide, Health Effects

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1 Fukushima Emergency Planning Zones, Use of Potassium Iodide, Health Effects Patricia A. Milligan, CHP Senior Technical Advisor Division of Preparedness & Response Office of Nuclear Security and Incident Response US Nuclear Regulatory Commission

2 Post Fukushima 1. Petition (2012) for rulemaking requesting NRC substantially expand existing emergency planning zones 2. Reconsideration of the basis of the emergency planning zone size as part of Near Term Task Force recommendations (NTTF) 3. Prestaging of potassium iodide beyond 10 miles (NTTF) 4. NRC committed to review information obtained from health studies on the impacted populations for potential impact on EPZ size and KI recommendations.

3 Emergency Planning Overall objective is to reduce dose for a spectrum of accidents that could result in doses offsite in excess of Environmental Protection Agency (EPA) Protective Action Guides (PAGs) 1 rem whole body at site boundary Two emergency planning zones (EPZ) around nuclear power plants. 10-mile plume exposure EPZ 50-mile ingestion pathway EPZ

4 Basis for EPZ Size Developed by joint NRC-EPA task force Decided that basis should be a consequence based approach Planning basis can be easily stated and understood in terms of the areas or distances, time frames, radiological characteristics and consequences from a range of accident possibilities Can identify planning elements and establish bounds on planning effort Provide consistency and uniformity in the amount of planning

5 10 mile EPZ 10 mile EPZ: doses from design-basis accidents would not exceed PAG levels outside EPZ; doses from most core damage accidents would not exceed PAG levels EPZ; For the worst core damage accidents, immediately lifethreatening doses would generally not occur outside the zone; Detailed planning within the 10-mile zone would provide a substantial base for the expansion of response efforts in the event that this proved necessary.

6 50 mile EPZ 50 mile EPZ: downwind direction which contamination will not exceed PAGs is about 50 miles due to wind shifts; likely conversion of atmospheric iodine to chemical forms that do not readily enter the ingestion pathway; most of particulate material in plume will deposit on ground within about 50 miles; the likelihood of exceeding ingestion pathway PAGs at 50 miles is comparable to the likelihood of exceeding plume exposure pathway PAGs at 10 miles.

7 Determination of Adequacy of Current EPZ Size NRC studied the efficacy of evacuations implemented by OROs within the United States: NUREG/CR-6864, Identification and Analysis of Factors Affecting Emergency Evacuations, (ML )

8 Determination of Adequacy of Current EPZ Size NRC studied overall emergency preparedness planning and response to 10 large scale disasters that affected over 10 million people: NUREG/CR-6981, Assessment of Emergency Response Planning and Implementation for Large Scale Evacuations, No. ML )

9 Events studied: Determination of Adequacy of Current EPZ Size large public evacuations due to technical hazards, malevolent acts, and natural disasters All were successful in saving lives with minimal to no fatalities Many of these evacuations were no-notice events

10 Determination of Adequacy of Current EPZ Size NRC emergency classification scheme (10 CFR 50.47(b)(4)) is anticipatory: offsite protective actions begin prior to release protective actions begin rapidly time available for actions beyond EPZ should it be necessary Spectrum of accidents include very unlikely rapid release events

11 Lessons from Fukushima EPZ Size Accident developed very slowly compared to the rapidly developing accidents used as basis for EPZ size Populations most at risk were evacuated prior to initial releases under very difficult conditions Doses to the public were very low lifetime radiation-induced cancer risks are small and would not be detectable amongst the background cancer rates

12 KI Distribution KI is a supplemental protective measure NRC agreed to supply/replenish KI for requesting States with populations within 10 mile EPZ To date NRC has distributed ~48,000,000 tablets Need to expand beyond 10 miles?

13 Lessons from Fukushima KI Use Use of KI was not implemented uniformly Most, if not all, areas populations were already evacuated when KI decisions were made Very little KI was administered to the populationanecdotal use of KI Prompt interdiction of food/milk/water prevented uptakes

14 Lessons from Fukushima KI Use Thyroid doses very low amongst the pediatric population <0.1 rad- ~10 rad upper bound No increases in thyroid nodules or other evidence of thyroid disease Extensive testing has revealed a higher rate of thyroid nodules in the pediatric population of Japan Control prefectures have similar rates as exposed prefectures

15 Fukushima Health Effects Fukushima Medical University Health Management Survey long-term study of population around Fukushima ~449,000 respondents ~ 99.8% whole body doses <500mr-2.5rem average effective dose received annually in Japan from natural background radiation is about 200 millirem Long term monitoring for impact on child thyroid

16 Fukushima Impacts on Health The most important health effect is on mental and social well-being, related to the enormous impact of the earthquake, tsunami and nuclear accident, and the fear and stigma related to the perceived risk of exposure to ionizing radiation UNSCEAR 2013

17 Fukushima Impacts on Health Stochastic effects from radiation dose Whole body doses very low; likely no increases in cancer amongst the population Thyroid doses in children are low; increases in thyroid disease unlikely Deaths from evacuation Approximately 1600 people have died from effects of evacuation

18 Fukushima Evacuation Impact on Health ~ 90% of evacuation related deaths were for persons above 66 years of age. ~70% of these deaths occurred within the first three months of the evacuations. Deaths were attributed to physical and emotional effects as a result of evacuation and loss of all possessions

19 Fukushima Evacuation Impact on Health Transfer trauma the mental or physical burden of the forced move from their homes/hospitals/institutions for fragile individuals; When you evacuate a hospital intensive care unit, you cannot take patients to a high school and expect them to survive Delays in obtaining needed medical support due to loss of medical infrastructure due to earthquake and tsunami.

20 In conclusion Current EPZ size provides for adequate protection of public health and safety from radiation effects Distribution of KI for 10 mile EPZ provides for adequate protection of public health and safety Response can be expanded as needed beyond 10 miles

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