NSEN-619 -- G. A. Beitel

1. 2/19/2012 NSEN-619 -- G. A. Beitel 1 NS&E HLW - Class 2 Review spent fuel statistics and data from IDB Review HLW statistics and data from IDB Review 10 CFR 60 regulations on SF-HLW disposal HLW performance criteria, and material qualification procedures. HLW Repository WAC

2. 2/19/2012 NSEN-619 -- G. A. Beitel 2 SF Statistics from (Rev. 13) IDB Note: If you have a different Rev, 11, 12, or 13, the table numbers will be different, but the data will be almost the same 107 reactors Fig 1.1 (Rev. 11) with a P = 98 Gwe Fig. 1.1 (Rev. 13) Activity and power for 30,000 MWD/MTIHM (PWR) (Fig. 1.5 Rev. 11) Activity -1-2 MCi initially; 0.1 MCi after 100 years Power 8 � 0.5 kW first 100 years

3. 2/19/2012 NSEN-619 -- G. A. Beitel 3 Approximately 47,000 MTIHM (Figure 1.3) Discharge rate - 2000 t/y for 100 reactors Dimensions - Table 1.4 Fuel bundle (assembly) is 0.25 to 0.5 tonne HM Reference DOE SF Table 1-5 5700 MTHM, most of which is at Hanford (but low burn-up relative to commercial fuel.) SF StatisticsFrom Rev 13 IDB

4. 2/19/2012 NSEN-619 -- G. A. Beitel 4 Observe heat and radiation levels Radiation - use 1 (R/h) (m2 /Ci), i.e., at 1 m, 1 Ci of 1MeV gamma emitter will produce a field of 1 R/h 0.1 M Ci --> 105 R/h at 1 meter (For humans, 200 mR/h is close to limit; 400 rem is the LD50; for materials, plastics fail at 106 � 107 rad although not technically accurate, 1 R ~ 1 rem ~1 rad Heat 1 kW can produce centerline temperatures of 300 � 700 C depending on heat conductivity and canister.

5. 2/19/2012 NSEN-619 -- G. A. Beitel 5 Radiolysis Classically measured as �G� value G = number of atoms (or molecules) produced per 100 eV Values like 0.1 - 2 are typical Note since typically energy loss is 35 eV/ion pair G = 1 implies a conversion rate (ion pair leading to chemical reconfiguration*) of 30 % *simplest case is H2O (liquid) dissociating to H2 (gas); this process goes through intermediate steps of H2O+, H2O-, OH-, � (see http://www.mun.ca/biology/scarr/Radiolysis_of_Water.htm )

6. 2/19/2012 NSEN-619 -- G. A. Beitel 6 High-level Liquid Waste HLLW Details of the Pu/U separation will be addressed next week by Vince Maio Most commercial fuel is UO2 (sometimes written as U2O4; a black ceramic with a density of about 11 g/cc http://www.webelements.com/webelements/compounds/text/U/O2U1-1344576.html ; see http://www.unitednuclear.com/pellet.htm for a picture). Weapons production and some others use metallic fuel. The fuel is contained in stainless steel (FFTF), Al, or zirconium alloy (commercial) tubing. Recall that after it has �burned up� it may be 0.5% fp to 4% fp (commercial) or higher (submarine fuel). Dissolving the fuel may include the tubing (hull) or may be just the Uranium/uranium dioxide.

7. 2/19/2012 NSEN-619 -- G. A. Beitel 7 Dissolving Fuel The objective it to put the metal or oxide in solution with minimal added material Nitric Acid, HNO3, has universally been the choice; concentrated and boiling see http://www.uic.com.au/uicchem.htm ; or http://www.chem.ox.ac.uk/icl/heyes/LanthAct/A10.html for chemistry of Uranium 2HNO3 + U + 2 H2O => UO2 (NO3)2 + 3H2^ or 2HNO3 + UO2 => UO2(NO3)2 + 2H2^ Uranyl Nitrate is soluble in boiling water at >600 g/l http://www.laddresearch.com/wsmsds/21397.htm

8. 2/19/2012 NSEN-619 -- G. A. Beitel 8 Purex Flow Sheet

9. 2/19/2012 NSEN-619 -- G. A. Beitel 9 A Dissolver used at Hanford

10. 2/19/2012 NSEN-619 -- G. A. Beitel 10 Look at Volumes and Densities Consider 1 ton of spent UO2 fuel with a 4% burn-up; 1000 kg U, 40 kg of U-235 converted to fission products Initial Fuel was 235 g U + 32 g O2, or 267 g/mole 1000 kg HM has a mass of (267/235)*1000 = 1136 kg Density of 11 g/cc or 11 kg/l it had a volume of 100 liters It dissolves to UO2(NO3)2 which has 235 g of U/mole and a mass of 235 + 8*16 + 2*28 = 391 g/mole Since you can dissolve about (600/391)*235 ~ 360 g U/liter aqueous solution

11. 2/19/2012 NSEN-619 -- G. A. Beitel 11 Volumes and Densities, cont. Therefore it will take (1000/0.360) = 2800 liters to dissolve a ton of fuel. However, once you extract the HM (U and P) then you only have 40 kg of fission products, and at ~100 g/l, you should be able to have all of the remaining fission products in about 400 l of aqueous solution (a reprocessing article quotes 450 l/MTHM) The actual concentration will probably be dictated by the thermal heat which is high enough to produce boiling. The 40 kg of fission products, have an average atomic mass of (90 + 140)/2 = 115, and most form dioxides, so as dried oxides, they would have an atomic mass of 147, so the 40 kg of fp would have a mass of (including the oxides) of 40*147/115 = 51 kg of oxides.

12. 2/19/2012 NSEN-619 -- G. A. Beitel 12 Volumes and Densities, cont. The fission product oxides typically have a density of 1 - 2 kg/l (dry solids or dry crystals), so we end up with 20 to 40 liters of fission products (note that many of these will be non-radioactive by the time you measure them. But there are more than 10% of the fission products which are noble gasses (Kr and Xe) so the actual number is a little less. Nevertheless, with concentrated nitric acid in steel vessels, there will be almost as much iron, nickel, chromium, and whatever came along from the fuel tubing, also. Part of the point of this analysis is to make it clear to you that the fission products are a significant mass and volume of the actual HLW. And, the bottom line is that aqueous HLW in its concentrated form is about 400 to 500 liters per ton HM

13. 2/19/2012 NSEN-619 -- G. A. Beitel 13 HLW from Reprocessed SF Figure 2.1 ff. Volume - 300,000 m3 -- this is 10x that of Commercial SF Note that form the 500 liters per ton, you might guess that we reprocessed 300,000 MTHM in manufacturing weapons. However it varies as high as 3000 l/ton http://www.world-nuclear.org/uiabs93/ricaud.htm Activity - 1 GCi compared to 27 GCi for Commercial SF (GCi = 109 Ci) HLW composition - see Table 2.11 Hanford Waste And Table 2.13 SRS Waste

14. 2/19/2012 NSEN-619 -- G. A. Beitel 14 Plutonium Production From http://www.osti.gov/html/osti/opennet/document/pu50yrs/pu50yc.html The total DOE plutonium acquisitions for the period 1944 to September 30, 1994, were 111.4 metric tons. Of the 111.4 MT plutonium acquired, 104 MT were produced in Government reactors; 103.4 MT in production reactors, and 0.6 MT in nonproduction reactors. In addition, 1.7 MT were acquired from U.S. civilian industry, and 5.7 MT from foreign countries. This section describes each of the acquisition categories in detail. The Weapons Production Reactors operated at slight enrichment and dissolved most of the fuel hulls. Therefore it did take somewhere between 100 and 300 thousand tons to produce this Pu, and result in 300,000 m3 of waste. So our calculations are reasonable.

15. 2/19/2012 NSEN-619 -- G. A. Beitel 15 Composition Counting Tank, Glass, and Capsule wastes Hanford - 15 isotopes account for 413 MCi SRS - 20 isotopes account for 481 MCi Of those activities Sr-90/Y-90 plus Cs-137/Ba-137m account for 411 and 478 MCi respectively Therefore, for radiation estimation purposes, one can assume that after a few years, all radionuclides are Cs and the Sr pairs, with an error of 0.5%, with all of the penetrating gamma radiation arising from Ba-137m (of course this depends upon your objective.) The remaining long-term hazards are attributable to Am, Np, Pu, U, I and Tc.

16. 2/19/2012 NSEN-619 -- G. A. Beitel 16 Review of 10 CFR 60 Section 60.1, 60.2 Purpose and Definitions Section 60.21(c)(5) Need waste description Section 60.43 (b) Restrictions on waste Section 60.101 Technical Criteria, ff Section 60.111 Performance Objectives, ff Section 60.113 Barrier Performance, ff Section 60.122 Siting Criteria, ff Section 60.135 Waste Package, ff

17. 2/19/2012 NSEN-619 -- G. A. Beitel 17 Repository Regulations Note the regulations are clearly safety based. 10 CFR 60.42 �necessary to protect health and safety � and environmental values� 10 CFR 60.101 �will not constitute unreasonable risk to health and safety:� 10 CFR 60.111 �meet 10 CFR 20� 10 CFR 60.113 - Performance objectives (see next slide) + 50 y retrievability 10 CFR 60.135 - Waste Package Criteria

18. 2/19/2012 NSEN-619 -- G. A. Beitel 18 The Solution Deep (>300 m) Geologic Disposal 10,000 -100,000 year confinement (release rate from engineered barrier ), �1 part per 100,000 per yr.� Allocate first 1000 years to waste container �containment substantially complete� Next 10,000 years to Waste Form Next 100,000 years to Geologic Media

19. 2/19/2012 NSEN-619 -- G. A. Beitel 19 Waste Package Criteria Can�t compromise the geologic setting or underground facility Must consider: solubility, oxidation-reduction, corrosion, hydriding, gas generation, thermal effects, radiolysis,radiation damage, leaching, fire and explosion, and thermal No explosives, pyrophorics, free liquids, shall be solid and sealed, no particulates, noncombustible, plus Others(!)

20. 2/19/2012 NSEN-619 -- G. A. Beitel 20 Stable Man-Made Materials

21. 2/19/2012 NSEN-619 -- G. A. Beitel 21 What can meet these requirements? Look at geologically stable materials:

22. 2/19/2012 NSEN-619 -- G. A. Beitel 22 The Problem Transuranics (Np, Pu, Am, Cm) and Actinides (Ac, Th, Pa, U plus TRU) Long-lived beta/gamma emitters Ultimately dominated by Actinides: Am(241 and 243), Pu(239 and 240), and Np-237 and, Fission and Activation products I-129, Tc-99, C-14, Nb-94

23. 2/19/2012 NSEN-619 -- G. A. Beitel 23 First 1000 years, HLW has both high Radiation and Thermal Radiation is high enough to cause material damage; dislocations, embrittlement, stored energy, degradation of polymers, radiolysis Thermal implies there is enough heat to raise temperatures to 700 - 800 C After 1000 yr, HLW equivalent to TRU The Problem, cont.

24. 2/19/2012 NSEN-619 -- G. A. Beitel 24 The Solution Deep Geologic Disposal (see 10 CFR 60) 10,000 -100,000 year confinement Allocate first 1000 years to Waste Container Next 10,000 years to Waste Form Next 100,000 years to Geologic Media 10 CFR 63 changed this to less than one chance in 10,000 over 10,000 years that Performance Goals will be exceeded

25. 2/19/2012 NSEN-619 -- G. A. Beitel 25 10 CFR 63 See file Named Key Items in 10 CFR 63 (also read 10 CFR 63) 10 CFR 63 is Yucca Mtn specific It allocates everything to the license which allocates containment assurance to design and the performance assessment Does not place requirements on the waste form Waste form requirements contained in the Waste Acceptance Criteria Document

26. 2/19/2012 NSEN-619 -- G. A. Beitel 26 Current HLW Repository WAC Vitrified waste is specified as the �standard HLW form� that passes the �Product Consistency Test�, or equivalent The PCT leachate shall be �less than those of the benchmark glass� Observe, that HLW Repository WAC have to meet the 10 CFR 60 requirements, but do not have to equal them. Recent version of HLW WAC has deleted even reference to 10 CFR 60, instead have been referred back to Nuclear Waste Policy Act No RCRA regulated wastes accepted These last two essentially require a 2-ft diameter glass log that would last 100,000 years in 90C water. For details see Waste Acceptance Product Specifications for Vitrified High-level Waste Forms http://web.em.doe.gov/waps/

27. 2/19/2012 NSEN-619 -- G. A. Beitel 27 RCRA Regulated Wastes HLW is a mixed waste, but, from http://www.epa.gov/radiation/mixed-waste/mw_pg5.htm#vitri Vitrification is the process of converting materials into a glass-like substance, typically through a thermal process. Radionuclides and other inorganics are chemically bonded in the glass matrix. Consequently vitrified materials generally perform very well in leach tests. EPA has specified, under the land disposal restrictions, vitrification to be the treatment technology for high-level waste (55 FR 22627, June 1, 1990).

28. 2/19/2012 NSEN-619 -- G. A. Beitel 28 What Qualification is used? ASTM C1220-92 HLW Glass Leach Test MCC-1 ASTM C1285 PCT Nuclear Glass Product Control Test The objective is to develop a product with a leachability index greater than 12 Recall that the ANSI 16.1 Leach Test went for a leachability index greater than 6, and we saw that at LI=6, a 1cm cube can dissolve in less than a year. By extrapolation, at LI=12, it would last a million years PCT is a 7 day, 90C water dissolution test using 100 to 200 mesh crushed glass. Measure the B, Na, and Li leached.

29. 2/19/2012 NSEN-619 -- G. A. Beitel 29 HLW Repository WAC, continued Table 3 �Normalized PCT Leaching Release Rates for �Simulated LLW Glass Produced by the Westinghouse Plasma Process ������� Sample������������ Sodium���� Silicon���� Boron���� Lithium Test #1: �� W1G7-106T�������� 1.122�������� 0.198�������� 0.173���� 0.524 �� W1G7-015T�������� 0.296�������� 0.111�������� 0.097���� 0.508 �� W1G7-017T�������� 0.285�������� 0.092�������� 0.093���� 0.511 �� W1G7-019T�������� 0.198�������� 0.097�������� 0.070���� 0.527 �� W1G7-021T�������� 0.180�������� 0.097�������� 0.063���� 0.480 �� W1G7-023T�������� 0.192�������� 0.110�������� 0.068���� 0.477 Test #3: �� W1G7-304T�������� 0.553�������� 0.188�������� 0.155���� 0.203 �� W1G7-310T�������� 0.816�������� 0.235�������� 0.236���� 0.159 �� W1G7-317T�������� 0.650�������� 0.190�������� 0.174���� 0.124 SRTC Coupon�������� 0.51����������� 0.09���������� 0.52������ 0.27 EA Glass:���������������� 10.7������������ 3.8������������ 13.1�������� 9.4 � Example from http://www.westinghouse-plasma.com/llw.htm