Changes to EPA Radiological Stack Monitoring Requirements, and Ramifications on LANL Operations

1. Changes to EPA Radiological Stack Monitoring Requirements, and Ramifications on LANL Operations David Fuehne, CHP March 22, 2005 – AMUG Meeting LA-UR-05-1903

2. 2 Discussion Areas • EPA standard for radiological stack monitoring • 2003 changes to standard • Maintenance & inspection requirements • LANL impact • Design criteria for new stacks • LANL impact • Conclusions

3. 3 EPA Standard for Radiological Stack Monitoring • 40 CFR 61, Subpart H – DOE facilities • 10 millirem per year • Entire laboratory is one facility • Receptor is residence, school, business • Stack monitoring required if potentialemissions exceed 0.1 mrem per year • Normal operations • No credit for pollution controls (HEPA, scrubbers, etc.) • LANL – Meteorology & Air Quality group, Environmental Stewardship division • 28 monitored stacks

4. 4 Changes to the Standard in 2003 • Incorporate ANSI/HPS N13.1-1999 • Revision to 1969 standard • Maintenance & inspection criteria • Design criteria for samplers and emission stacks • Existing emissions sources • Grandfathered design • Maintenance & inspection criteria apply • New or Modified Stacks • All design criteria apply • M&I criteria

5. Maintenance & Inspection Criteria

6. 6 Maintenance & Inspection Requirements • Many minor items – calibrated electronics, clear rotameters, etc. • Stack sample system inspection program • Annual inspections • Nozzles, probes, sample lines • Proper alignment • Free from damage • Free from deposition • Clean the systems if deposition is observed • When? No guidance provided

7. 7 M&I Requirements:LANL Implementation Plan • Flexible borescope into stack lines • Focus on nozzle openings, probes, bends in sample lines • Record images – photos & video • 2003: Six systems with visible deposition • Two were easy to clean • Two were difficult to clean • Two were impossible Photo property of UXR

8. 8 M&I Requirements – LANL Implementation:Easy to clean Accelerator stack – discrete point of deposition • Caulking / sealant – HVAC maintenance? • Immediately removed during inspection • Small amount of rad material (sub-nanocurie Co-60) on cleaning material, include in annual source term

9. 9 M&I Requirements – LANL Implementation:Easy to clean Rad liquid waste treatment facility • Wet environment – condensed vapors • Straightforward cleaning - remove, wipe down, replace • Small downtime on sampler • No detectable rad material in cleaning solution, cloths • Completed within 60 days of discovery

10. 10 M&I Requirements – LANL Implementation:Difficult to clean • Research facility – two stacks • Straightforward problem, complex solution • Nuclear facility issues • Safety review process • Perchlorate concerns – bomb gear • Stack fan shutdown, coordinate with users • Oil mist on surfaces – HVAC maintenance • No detectable activity on surfaces, cleaning materials • Completed ~18 months after discovery

11. 11 M&I Requirements – LANL Implementation:Impossible to Clean • Nuclear facility, two stacks • Original stack samplers, ~ 30 years installed • Visible scale on external surfaces • Old design – 1969 samplers • Low transport efficiency <20% • Three 90-degree bends • Operation issues – restricted access, no backup samplers • Decision – Replace, not clean • Four sample rakes on each stack – independent • Roof level – simplify access • EPA agrees to plan • Deadline : Dec 2005 – 24 months after initial inspection

12. 12 Effects of Deposition on Emissions Data? • Already assume some particulate losses will occur • Assumed rate-of-loss based on large diameter particles • Emissions calculations correct for these assumptions • Double-count by including rad material from inspections in annual source term • Most cleaning shows NDA • One stack with sub-nanocurie levels • Result – no negative impact on program; conservatism is built-in

13. 13 Changes to M&I Program - Audit • Visually examine external surfaces as well as internal surfaces – inspect nozzle conditions • Record imagery each year • Formalize process with procedure, annual performance summary • Currently – IWDs, checklists

14. Design Criteria

15. 15 Design Criteria for New & Modified StacksSample probe performance • Recommend single-point shrouded probe • Nozzle transmission ratio 80-130% • Particle transmission to collection media >50% • 10 micron particles used for analysis

16. 16 Design Criteria for New & Modified Stacks:Sample location • Well-mixed, uniform flow • Justifies single point sampler • Flow angle > 20 degrees • Velocity profile COV < 20% • Aerosol concentration COV < 20% • Use 10 micron particles to test • Iterative process – pick location & test • Failure – test new location • Swiss-cheese stack

17. 17 Design Criteria for New & Modified StacksComplicating factors When do these criteria apply? • New source, including new construction in existing buildings • Modification of existing source • Modification must cause increase in off-site dose >0.1 millirem/yr • Certain activities are NOT modifications • Review new activities for sampler system design adequacy

18. 18 Design Criteria for New & Modified StacksComplicating factors LANL stacks – Seven systems meeting design criteria • Locate new ops in these buildings More reviews required, more manpower requirements • EPA notification timeline • Monitoring yes/no/what • System design adequacy

19. LANL Example Waste Repackaging Facility

20. 20 Design Criteria, LANL Example:Waste Repackaging Facility • Original plan – new construction • Easy to meet requirements • Tall stack, smooth transitions, “clean” system to test • New plan – retrofit existing system • Poor fan-to-stack transitions • Aerosol injection points • Accessing sampling points – scaffolding • Problems generating 10 um aerosol in quantity • Stack tests unsuccessful

21. 21 Design Criteria, LANL Example:Waste Repackaging Facility • Move sampler to new location – glove box exhaust • Long straight runs • Lower air volume to dilute aerosol • Concern – facility as a whole is not monitored, just primary glove box operation

22. 22 Design Criteria, LANL Example:Waste Repackaging Facility Lessons Learned • Time Line • Entire process – six months to get approved location • Capability to perform these tests in the future • Aerosol R&D team dissolved years ago • MAQ stack engineering team “streamlined” • Collaboration among 3+ groups required – priorities? • Rely on outside vendors – clearances, training, schedule

23. LANL Example TRU Waste Vitrification

24. 24 Design Criteria, LANL Example:TRU Waste Vitrification • New process at LANL = new source of emissions • Off-site dose potential over 0.1 millirem per year • Retrofit existing stack? Cannot meet design criteria • Cannot change buildings – material concerns • Solution – brand new stack(s) • Not same as sampler upgrade discussed earlier • Capital funding required; multiple years delay • Operations cannot commence until upgrade complete

25. Conclusions

26. 26 Conclusions New maintenance & inspection criteria • Routine inspection requirements are good improvement • Cleaning activities can impact facility operations • “Gray area” on time window for completion of cleaning activities • Compliance issues could arise if cleaning operations delayed

27. 27 Conclusions, continued Design criteria • Additional workload for new process reviews • Retrofitting existing systems can be problematic • Testing capability at LANL may not be available • Iterative testing can be frustrating • Can result in significant delays for planned operations

28. 28 Thanks for your time! • Questions or comments? David Fuehne LANL ENV-MAQ 505-665-3850 davef@lanl.gov http://www.airquality.lanl.gov external web site