AIRBORNE EMISSIONS AND MONITORING OF PLUTONIUM FROM ROCKY FLATS W. Gale Biggs, PH.D.

1. ROCKY FLATS: A CALL TO NUCLEAR GUARDIANSHIPCo-Sponsored by Rocky Mountain Peace and Justice Centerand the Naropa University Environmental Studies Programs AIRBORNE EMISSIONS AND MONITORING OF PLUTONIUM FROM ROCKY FLATS W. Gale Biggs, PH.D. March 17, 2011

2. Most of the information presented comes from Dr. Biggs’ participation on the following three committees: • Rocky Flats Scientific Monitoring Panel (Appointed by Governor Romer) • Rocky Flats Cleanup Commission (an EPA TAG group) • Rocky Flats Citizen Advisory Board (a DOE sponsored group)

3. Two items will be covered: • PU emissions • Monitoring of airborne concentrations

4. PU EMISSIONS • Stack Emissions • Fugitive Emissions • Reflotation / Surface disturbance • High Wind Events • Events – (Will Not Discuss These Events) • Fires • Accidents

5. PU STACK EMISSIONS • Stack emissions pass through banks of HEPA filters • Average size of PU particles in building ducts is 0.045 microns • Average size of a human hair is about 50 microns

6. PU FUGITIVE EMISSIONS How much of the plutonium leaving Rocky Flats was from fugitive sources? • The amount is unknown, but estimates were from 60% to 99% • Fugitive PU emissions are due to: • Surface disturbance by human activities • Wind • Bottom Line • Fugitive emissions are unknown • But they account for the majority of PU emissions from the Rocky Flats facility

7. PU PARTICLE SIZE • Soil emissions (fugitive) consist of both small and large particles • Stack emissions are very small particles since they pass through several banks of HEPA filters

8. ALPHA-RECOIL EFFECT • This effect occurs when the PU molecule emits an alpha particle (radiational decay) • Alpha decay generates enough energy to blast a piece of PU off the particle

9. ALPHA-RECOIL EFFECT • This effect occurs when the PU molecule emits an alpha particle (radiational decay) • Alpha decay generates enough energy to blast a piece of PU off the particle

10. ALPHA-RECOIL RESULT Due to alpha recoil effect: • Particles decrease in size • Increase in number

11. The fugitive emissions are the dominate source for airborne PU from the Rocky Flats THE NEXT SLIDES WILL DISCUSS THE STACK EMISSIONS

12. STACK EMISSION ESTIMATES • Look at an exhaust duct from building 707 • The pitot tube measures the air flow through the duct and is used to calculate emission concentrations • The radiological monitors are designed to measure radiation through the duct

13. Air Flow Pitot Stack exiting roof Radiological Monitors BUILDING EXHAUST DUCT Top View

14. PROBLEMS WITH DUCTS • The pitot tube had not been calibrated since it was installed when building 707 was built, therefore the amount of air flow in the duct is unknown • The air movement for measuring radioactivity was flowing backwards NEXT SLIDE SHOWS THIS

15. Air Flow Pitot Stack exiting roof Radiological Monitors Rotary Air Flow in Duct Top View

16. PU STACK EMISSIONS • The air flow through the duct was unknown • The amount of PU in the duct was unknown • Therefore the PU emissions from the stack were unknown

17. HOW GOOD WERE THE EMISSION ESTIMATES? • We just showed that the stack emissions were unknown • The fugitive emissions were unknown Bottom line – the DOE did not know how much PU was being emitted into the ambient air from Rocky Flats

18. AMBIENT MONITORING Since the emissions were not known, could the monitors perhaps indicate the amount of PU coming off the Rocky Flats plant? Unfortunately – NO!!!

19. PU IN THE AIR • We earlier showed that the stack PU particles going into the air are very small • The airborne stack particles are probably smaller than 0.01 microns

20. PU IN THE AIR • However, some of the small particles attach to larger particles in the atmosphere • Examples of larger particles in the atmosphere are: • Pollen • Organic matter • Fugitive particles can be either small or large depending on surface activity and wind speed

21. AIRBORNE PU PARTICLE SIZE • The next slide shows the range of airborne particle sizes for PU and the collection range of the high volume air sampler • Both the initial particle size as well as those attached to larger particles are shown • Pollen and organic matter in the atmosphere usually range in size from about 15 to several hundred microns

22. 0.001 0.01 0.1 1 10 100 Particle Size Sampling Range for HiVol Sampler Particle Size Range for Dispersed PU Particle Size Range for Wind Blown PU Particulate Size (microns)

23. MONITORS ADEQUATE? • No – the monitors are inadequate • The air monitors are not sampling the airborne PU which is being emitted from the Rocky Flats site. Bottom line – we do not know the ambient concentration of PU emissions leaving the Rocky Flats site

24. ROCKY FLATS HEALTH ADVISORY PANEL • The Rocky Flats Health Advisory Panel, at the end of their Phase I analysis stated that the most dangerous health exposure to the public was from the airborne pathways • Since we do not know the emissions, the extent of the health problems is not possible to estimate

25. CONCLUSIONS • We do not know how much PU is (or was) being released from the Rocky Flats site • The majority of the PU emissions are from the soil being disturbed by both activity on the site and from wind blown dirt • The ambient air monitors are not representative of the airborne PU concentrations • PU probably travels some distance before settling • Population is exposed to PU by air pathways before settling occurs • PU in the air is not taken as seriously as it should be