Radioactive Waste Overview

1. Radioactive Waste Overview • High Level Radioactive Waste The U.S. NRC describes high-level radioactive wastes as the highly radioactive materials produced as a byproduct of the reactions that occur inside nuclear reactors. High-level wastes take one of two forms: • Spent (used) reactor fuel when it is accepted for disposal • Waste materials remaining after spent fuel is reprocessed Spent nuclear fuel is used fuel from a reactor that is no longer efficient in creating electricity, because its fission process has slowed. However, it is still thermally hot, highly radioactive, and potentially harmful. Until a permanent disposal repository for spent nuclear fuel is built, licensees must safely store this fuel at their reactors.

2. Low Level Radioactive Waste • Classes of Waste • Class A • Class B • Class C • Three existing low level radioactive waste disposal facilities • Barnwell, SC • Hanford, WA • Clive, UT

3. Low Level Radioactive Waste • Waste is disposed in Low Level Disposal Facilities.

4. Low Level Radioactive Waste • Low Level Radioactive Waste is encapsulated either by solidification or placement in High Integrity Containers.

5. High Level Radioactive Waste

6. Fuel Rods Filled With Pellets Are Grouped Into Fuel Assemblies

7. Fuel Assemblies Cool Temporarily in Used Fuel Pools

8. Dry Fuel Storage at Plant Sites

9. Temporary Dry Fuel Storageat Power Plant Site

10. Dry Fuel Storage Projects • ENERCON Services has provided engineering services for 18 Dry Fuel Storage Projects throughout the US.

11. Dry Fuel Storage Projects • Dry Fuel Storage Projects include design and engineering for: • Storage Pad • Facility Security • Electrical • Federal Licensing • Local and State Permitting • Cask Heavy Load Lifting

12. Transportation Containers Are Strong and Safe

13. Transportation Casks Have Been Tested

14. Container Loaded on a Truck…

15. … And Crashed at 80 MPH into a Concrete Wall

16. Container Broadsided by Locomotive Traveling at 80 MPH

17. Containers Survived Incineration Tests

18. Containers Passed Every Test

19. NRC Concludes Shipping Even Safer Than Previously Thought

20. At the Repository, Fuel Will Be Transferred to a Special Disposal Container

21. Yucca Mountain Being Considered As Disposal Site

22. Yucca Mountain Being Considered As Disposal Site

23. Seven Miles of Tunnels Built in Yucca Mountain

24. Yucca Mountain Has Been Thoroughly Investigated

25. President Recommends Yucca Mountain

26. New Nuclear Power and Climate Change: Issues and Opportunities Lunch Keynote Presentation William Sweet Senior News Editor IEEE Spectrum

27. New Nuclear Power and Climate Change: Issues and Opportunities Student Presentation Ashish K Sahu and Sarina J. Ergas University of Massachusetts - Amherst

28. Perchlorate Reduction in a Packed Bed Bioreactor Using Elemental Sulfur Ashish K Sahu and Sarina J. Ergas

29. Background • Perchlorate (ClO4-) • Stable • Non reactive • Trace levels of Perchlorate • Disruption of hormone uptake in thyroid glands

30. Geographic Contamination • No National Standards • MCL set by the Commonwealth of Massachusetts (2 mg/L) • California advisory levels (6 mg/L) • Other states (NY, NV, AZ, CO, TX) 18 mg/L Ref: ewg.org

31. Sources of Perchlorate • Natural • Atmospheric Sources • Chilean nitrate fertilizer • Anthropogenic • Missiles, Rockets • Fireworks • Leather Tannery Industries • Fertilizers

32. Treatment Processes • Physical Processes • Chemical Processes • Biological Processes • Combination of the above

33. Perchlorate Treatment Processes Physical Destructive Process Hybrid Technologies Chemical Biological GAC Bioreactors Others RO/NF CC-ISEP Phytoremediation Reducing metals IX Electrodialysis Others (MBR) CSTR PFR Bio-remediation

34. Outline • Biological Perchlorate Reduction • Use of Elemental Sulfur • Experimental Protocol • Results • Conclusions

35. Heterotrophic microorganisms Use organic carbon as their carbon source Electron donors are methanol, lactate, ethanol, wastewater Autotrophic microorganisms Use inorganic carbon as their carbon source eg: NaHCO3 Electron donors are S, Fe0, H2 Biological Perchlorate ReductionPrinciple: Microorganisms convert perchlorate to chloride

36. Use of Elemental Sulfur 2.87 S + 3.32 H2O + ClO4- + 1.85 CO2 + 0.46 HCO3- + 0.46 NH4+→ 5.69 H+ + 2.87 SO42- + Cl- + 0.462 C5H7O2N • Electron Donor: Elemental Sulfur • Electron Acceptor: Perchlorate • Carbon Source: Bi-carbonate • Low biomass production • Low nutrient requirements • Anoxic conditions • Alkalinity destroyed

37. Advantages of Elemental Sulfur • Waste byproduct of oil refineries • Excellent packing media • Relatively inexpensive and easily available • Applications in packed bed reactors and permeable reactive barriers

38. Objectives • Enrich a culture of Sulfur Utilizing Perchlorate Reducing Bacteria (SUPeRB) • Investigate the use of packed bed bioreactors to treat perchlorate contaminated waters by SUPeRB • Test the bioreactor for varying operating conditions

39. Batch Culture Enrichments • Denitrification zone of Berkshire wastewater treatment plant, Lanesboro, MA • 5mg/L ClO4-, So and oyster shell, nutrients in groundwater • Analytical Techniques • pH • ClO4- concentration using IC (EPA method 314.0)

40. Batch Culture Enrichment (SUPeRB)

41. Packed Bed Reactor • Reactor inoculated with SUPeRB • Media: Elemental Sulfur pellets (4 mm), oyster shell (3:1 v/v) • Volume: 1 liter • Ports: 5 ports

42. Packed Bed Reactor Operation

43. Bioreactor Performance-Phase II(Effect of Empty Bed Contact Time (hrs))

44. Bioreactor Performance-Phase II(Effect of Empty Bed Contact Time)

45. Bioreactor Performance-Phase II(Effect of sulfur size particles)

46. Bioreactor Performance-Phase II(Effect of Nitrate on Perchlorate Removal)

47. Summary • SUPeRB reduced ClO4- from 5 mg/L to <0.5 mg/L in 15 days using S0 and OS • High levels of perchlorate (5-8 mg/L) were successfully reduced to < 0.5 mg/L in the bioreactor at an EBCT of 13 hours • Low levels of perchlorate (80-120 mg/L) were reduced to < 4 mg/L at an EBCT of 8 hours

48. Summary… • Presence of nitrate did not inhibit perchlorate reduction • Perchlorate reduction was somewhat independent of media particle size

49. Applications and Future Work • Pilot scale of system for perchlorate remediation • Ex-situ remediation • In-situ remediation by Permeable Reactive Barriers (PRBs)

50. Acknowledgements • Water Resources Research Center (WRRC), TEI at UMass-Amherst • Massachusetts Technology Transfer Center (MTTC) for commercial potential • Advisor: Dr. Sarina Ergas • Teresa Conneely, Department of Microbiology for FISH and microbiology analysis • Tach Chu and Charlie Moe (High School) for culture and bioreactor maintenance