ML20203P968

Advises That Engineering Branch of Div of Waste Mgt Performing Review of Nuclear Packaging,Inc Rept,Submerged Demineralizer Sys Liner Qualification as High Integrity.... Request for Addl Info & Draft Ltr to State of Wa Encl

ML20203P968
Person / Time
Issue date:	04/18/1986
From:	Knapp M NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
To:	Nussbaumer D NRC OFFICE OF STATE PROGRAMS (OSP)
References
REF-WM-87 NUDOCS 8605080442
Download: ML20203P968 (16)

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WM-87 / YYoung NMSS r/f KSchneidzr WMEG r/f EEscalante, NBS APR 18 g REBrowning CMacDonald WMEG/JCV/SDS COVER LETTER 2 "9 ves TJohnson MNataraja MTokar MEMORANDUM FOR: Donald A. Nussbaumer JVoglewede Assistant Director for J1inehan State Agreements Program MKnapp Office of State Programs PJustus J0 Bunting FROM: Malcolm R. Knapp, Acting Chief Low-Level Waste and Uranium Recovery Projects Branch Division of Waste Management

SUBJECT:

REVIEW 0F HUPAC TOPICAL REPORT The Engineering Branch of the Division of Waste Management, NMSS, is performing a review of the Nuclear Packaging, Inc. (NUPAC) report entitled "SDS Liner Qualification as a High Integrity Container." The report describes the use of Three Mile Island Unit 2 Submerged Demineralizer System (SDS) vessels as High Integrity Containers for low-level radioactive waste disposal at the Hanford, Washington site. Because the State of Washington has the responsibility for regulating commercial disposal at that site, we are forwarding the attached request for additional information on the vessel design to the appropriate officials for transmittal to the applicant.

To facilitate the transmittal of this request, we have enclosed a draft letter for your signature to the State of Washington. References cited in our request that may be difficult for the applicant to obtain are also provided.- If there are any questions on this matter, please contact John Voglewede on x74275.

M 8mt,cmerwy Malcolm R. Knapp, Acting Chief Low-Level Waste and Uranium _

Recovery Projects Branch Division of Waste Management

Enclosures:

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As stated VlM Record File WM Project $7 Docket N3. -

i PDR / l 8605080442 860418 PDR WASTE PDR LPDR WM-87 Distribut ion:

{ Return to WM,623 SS) 0FC :NMSS/WM NMS EG :NM :NMSS/WM  :  :

NAME :JCVoglewede :T nson :J eeves :MRKnapp  :  :  :

DATE :04/16 /86 :04/gh/86 :04/\b/86 :04/ (4 /86  :  :  :

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Mrs. Nancy P. Kirner, Supervisor Radiation Control Program Department of Social and Health Services Mail Stop LD-11 Olympia, WA 98504

Dear Mrs. Kirner:

As stated in your letter of March 6, 1985, Nuclear Packaging, Inc. (NUPAC) has submitted a generic topical report on their Submerged Demineralizer System High Integrity Container. The Division of Waste Management is presently reviewing this topical report in accordance with provisions of 10 CFR 61. They have generated the attached comments and a request for additional information to support the review effort. Please review this document and forward it to the applicant for resolution.

If you have any questions, please contact Kathleen N. Schneider at (301) 492-9893.

Sincerely, Donald A. Nussbaumer Assistant Director for State Agreements Program Office of State Programs

Enclosure:

As stated

. NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL The following comments and questions apply to the review of the Nuclear Packaging, Inc. (NUPAC) report (Ref.1) entitled "SDS Liner Qualification as a High Integrity Container." This report, transmitted by letter dated November 21,1984 (Ref. 2) and supplemented by letter dated March 19, 1985 (Ref. 3),

describes the use of Three Mile Island Unit 2 (TMI-2) Submerged Demineralizer System (SDS) vessels as High Integrity Containers (HIC) for low-level radio-active waste disposal at the Hanford, Washington site.

1. Section 1.0, Page 1-1 It is stated that nineteen vessels, which contain the bulk of the accident-released curies, were disposed of by the U.S.

Department of Energy (DOE), Please provide a list of all SDS vessels processed or anticipated from the TMI-2 cleanup. Identify each vessel and indicate actual or anticipated curie loading, the vessel design and material (if different from that described in the report), and the disposal mode (commercial or DOE).

2. Section 1.1, Page 1-1 Is the SDS vessel qualification intended to apply only to the Hanford low-level radioactive waste disposal site?

, 3. Section 1.1, Page 1-2 In the first sentence of this page, those vessels disposed of by the DOE are additionally qualified as " zeolite-containing." '*

This suggests that SDS vessels containing material 01.her than zeolite were also disposed of by the DOE. Do all the DOE and the commercially-handled vessels contain only zeolite or zeolite / sand mixtures?

4. Section 1.2, Page 1-2 Do the ASME Section VIII requirements cited in this section refer to ASME Section VIII, Division 1 requirements?

5. Section 1.2, Page 1-2 Provide a description of the Johnson screens used to filter particulates from the water and gas ports. Is a particulate barrier necessary after burial to preserve the integrity of any container seal?

6. Section 1.2, Page 1-3 Design drawings submitted by letter dated March 19, 1984 (Ref. 3) should be amended to provided a description of the post-burial vessel venting system.

7. Section 1.3, Page 1-4 What are the total quantities of sand and zeolite used in the vessels identified in response to Question 1. How many vessels con uin only sand, how many contain only zeolite, and how many contain a n. 4ture of both? What is the composition of the sand?

8. Section 1.3, Page 1-4 England and Wilson (Ref. 4) have determined the total TMI-2 inventory of Cs-137 and Sr-90 as 736,000 Ci and 699,000 Ci, respectively, at 5.7 years following the accident. The recommended upper load limits on the vessel for cesium and strontium are 60,000 Ci and 2,000 1

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.- NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL Ci, respectively. Thus the load limits reflect a 30:1 cesium-to-strontium ratio rather than a nearly 1:1 ratto calculated by England and Wilson. Is this difference primarily due to the preferential absorption of cesium by the ion exchange media, or to a higher cesium inventory in the reactor building water. Has the actual ratio been confirmed by radiochemical measurement?

9. Section 1.3, Pag? 1-4 What other radionuclides are present in the reactor' building water? What are the maximum expected vessel inventories of radionuclides other than cesium and strontium? Have these expectations been confirmed by radiochemical analysis? Please provide data to confirm this position.

10. Section 1.3, Page 1-4 Note that the upper limits fer container content result in wastes which exceed the Class C limits and are are generally unsuitable for near-surface disposal. Provide a description of the process control limits (curies of cesium, strontium, and transuranic waste (TRU) per vessel) used to assure conformance with 10 CFR 61.55, Table 2.

How is conformance with the process control limits determined? How is the conformance verified?

11. Section 1.3, Page 1-4 What is the chemical composition of the waste being processed by the Submerged Demineralizer System? Provide a conservative projection of the chemical content of the waste.

12. Section 1.4, Page 1-5 Is the orientation of the vessel a significant i' factor in its post-burial performance? If so, how will proper orientation be assured during the burial process? What are the consequences of improper burial orientation? Note that burial of wastes in the Class B and C part of the Hanford trench can not ensure upright configurations.

! 13. Section 2.2.2, Page 2-2 Why is the burial environment at Hanford assumed to be deaerated? Please provide the data used to support this position.

, 14. Section 2.3, Page 2-3 Based on arguments presented in Appendix B, it is i concluded that "Even with . . . conservative assumptions, pitting i penetration of the 0.375 in. thick SDS vessel wall would not occur in less

! than 300 years." The following sentence states that " Pit densities might be greater in the welded regions due to the higher susceptibility of ~

welded Type 316 to pitting than the unwelded material." This implies that

. the minimum expected container lifetime should be based on pitting penetration of the vessel welds rather than the unwelded vessel wall. How does this implication affect the conclusions of the report?

15. Section 2.3, Page 2-3 During the course of our review (Ref.-5) of another NUPAC high integrity container (the FL-50/EA-50 Ferralium 255 HIC), it was shown (Ref._6) that the corrosion resistence of austenitic stainless 1

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. NUPAC SUBMERGED DEMlNERALIZER SYSTEM VESSEL steels (such as that used in the SDS vessel design) is demonstrably worse than the duplex (austentic-ferritic) alloy selected for the NUPAC FL-50 application. In light of this information, why is the austenitic material suitable for the SDS application?

16. Section 3.2, Page 3-1 The citation for Type A conditions should be 49 CFR (Transportation) rather than 10 CFR (Energy). It would be preferable, however, to reference the normal conditions of transport in 10 CFR 71.71.

17. Section 3.2.2, Page 3-2 What is the basis for the statment that there is no explosion potential at 130 F?

18. Section 3.3, Page 3-4 The SDS vessel does not incorporate a tamperproof feature nor is it shown that lifting devices, whicn could be used as tie-down devices, meet the requirements for a Type A package. Will the SDS vessel be shipped in an NRC-approved transport cask, which satisfies these concerns?

19. Section 3.4.1, Page 3-5 Note that the State of Washington has modified the mechanical loading requirements to include a 45 foot burial depth and an addition of 10 feet of overburden (Ref. 7). The total design load is 55 feet of material with a density of 120 pounds per cubic foot. The discussion should be revised to addressed these revised loading conditions.

20. Section 3.4.1, Page 3-5 The section on burial loads does not appear to account for the effects of lateral pressure on the vessel. What lateral loading is considered in the stress and buckling analysis of the vessel?

21. Section 3.4.1.1, Page 3-5 The maximum principal stress points in the model of the SDS vessel do not coincide with the points of geometric discontinuity in this model (the weld points). Is this a result of the radial support provided by the upper and lower skirts, or are the same critical points obtained without considering the vessel skirts?

22. Section 3.4, Page 3-5 The Proposed HIC Structural Criteria, Revision 1 (Ref. 8), as modified by the NRC staff (Ref. 9), should be used as a basis for the structural analysis of the SDS vessel.

23. Section 3.4.3, Page 3-11 What is the basis for the statement that Type 316L stainless steel is not susceptible to radiation damage? l

24. Section 4.0, Page 4-1 Provide a description of the manner in which the Hansen quick-disconnect couplings are sealed prior to disposal. Identify 1

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. NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL the materials involved in the seal. Will the quick disconnect feature of the coupling compromise the integrity of the resulting seal?

25. Section 4.0, Page 4-1 Is the graphite fiber seal in contact with soil or any electrolyte? Provide the technical data use to support the NUPAC conclusion that the graphite and Flexitalic seals will not be chemically reactive with the internal and external conditions. Graphite is known to be noble in electrical potential to most metals as indicated in the Galvanic Series in sea water (Ref.10). This difference in potential can cause the surrounding metal to behave as an anode, causing it to preferentially go into solution.

26. Section 4.0, Page 4-1 Provide a description of the Flexitalic gasket used to seal the fill ports on the vessel upper pressure head. Is an 0-ring involved in this seal? If an 0-ring is involved, which seal (gasket or 0-ring) provides the primary seal boundary? Describe the procedure used to install the blind flanges on these corts.

27. Section 4.0, Page 4-1 Provide a description of the vessel vent, rupture disk, and porous vent plug. Identify the component materials and describe the procedures used to prevent venting while the vessel is shipped and any changes required prior to burial. What is the rupture pressure of the disk? Is the rupture disk considered part of the primary seal boundary?

Is the rupture disk included because of ASME Section VIII Code requirements?

28. Section 4.0, Page 4-1 If other sealing materials are involved in the SDS vessel design, identify the materials use and describe the sealing techniques employed. ,

29. Section 4.1, Page 4-1 Graphite is not very reactive, but, like gold, it can cause other metals to behave as anodes causing them to corrode sacrificially as described above.

30. Section 4.2, Page 4-2 Provide technical data to support your conclusion that sealing materials are stable in radiation fields.

31. Section 4.1, Page 4-2 While the precipitation rate at Hanford is low, the infiltration of water or other liquids from wastes buried above is an issue which needs to be addressed.

32. Section 4.1, Page 4-2 Concerns have been raised (Refs. 11-12) regarding corrosion of the liner material from the inside out due to contact with the contents or contact with the byproducts of irradiation breakdown.

NRC-sponsored studies (Ref.13) indicate that the effects of irradiation on zeolites are not significant. Does this conclusion also apply to sand 4

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL and waste composition expected in the SDS vessel? Please provide the data used to support this position.

33. Section 5.0, Page 5-1 Note that the State of Washington restricts pressurized containers in the U.S. Ecology license conditions.

Section 5.0, Page 5-1 The following design criteria and information

, requirements are taken from the State of South Carolina's " Guide for Passive

Vent Design Submittals" (Ref. 14).

General Design Criteria: Venting systems for high integrity containers (HIC) shall be designed to minimize degradation of the container's integrity but maximize venting of gas buildups. The design should take into account, as a minimum, the effects of burial loads, compression, l clogging and/or puncturing, vibration, container drops, radiation, thermal i

cycling, biodegradation, and corrosion. Vents shall be located in such a manner as to avoid being damaged during loading, handling, and disposal.

l The following information shall be submitted for evaluation of passive vent designs for high integrity containers:

-34. A detailed section drawing showing the design and location of the

, vent. If the same design and location is to be used for containers

of different sizes, only one drawing will be necessary.

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35. A detailed description of the vent, its composition, and how it is to be installed or incorporated into the container.

36. An evaluation of the. effectiveness of the vent in relieving gas buildups to include the rate, quantity, and types of gases it will handle, and the effects of internal liquids or moisture on the vent performance.

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37. An evaluation of the vent on the overall effect on the integrity of

, the container, handling and any precautions to be taken when placing-the container in the trench and backfilling.

38. At least one filled container snall be tested to evaluate the performance of the installed vent. The test shall represent, as

! accurately as possible, the conditions for which the container will be subjected, e.g., loading, handling, pressure, stacking, transportation, etc. The results of this test shall be submitted.

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39. Section 6.2, Page 6-2 Why were drop tests on the flat bottom not l pe.-formed? Please provide test data or an analysis to demonstrate that the flat bottom drop is bounded by other drop testing actually performed.

40. Section 6.3, Page 6-3 A figure showing the damage following the 25 foot drop test on the bottom corner should be provided.

41. Section 7.0, Page 7-1 Appendix A does not correlate the amount of liquid remaining in the SDS vessel with the 1 percent free liquid requirement.

Appendix A shows there will be less than 100 lb of residual water, but does not show that less than 1 percent of the container volume would be released if punch tested in accordance with ANS 55.1.

42. Section 7.0, Page 7-4 The NUPAC report states that the NRC's Branch Technical Position on Waste Form (Section C.4.h, Biodegradation, -

Ref.15) is not applicable to the SDS vessel. Technical information

.should also be provided to support this position. In light of the fact that iron alloys have been known to corrode in the presence of anaerobic, sulfate-reducing bacteria, please explain why this section of the Branch Technical Position is not applicable.

43. Section 7.0, Page 7-5 Are drain slots also placed in the bottom skirt?

Note that upright burial cannot be assured at the Hanford site.

44. Section 7.0, Page 7-6 The NUPAC report states that "All phases of the manufacture, use and burial are covered by specifications and procedures that undergo QA review and inspection programs that comply with 10 CFR 50, Appendix B. Please describe how compliance with Appendix B has been determined. The fabrication Quality Assurance (QA) program should be provided for our review. A more detailed discussion of the quality control procedures for loading, operation, and handling should also be provided. Any special burial site operational conditions should also be identified.

45. Section 7.0, Page 7-7 It is unclear what is meant by stating a HIC qualified vessel inherently provides assurance that the contents are not deterimental to the container materials. Clearly the HIC qualification will be based on the acceptability of specific waste streams. The purpose of the quality assurance program is to ensure that other wastes which were unreviewed are not placed into the HIC's.

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL The following ccmments and questions apply to Appendix A, " Submerged Demineralizer System Vessel Shipment Report" (Ref. 16), which considers the generation of radiolytic hydrogen and oxygen gases within the SDS vessel.

46. Appendix A, Page 14 The discussion of internal gas generation in this report . suggests that a nonstoichiometric mixture of hydrogen and oxygen will be formed in the vessel due to some oxygen being depleted rather than recombined. What are the consequences of the hydrogen-rich atmcsphere in the vessel ?

47. Appendix A, Page 14 Considering the imperfect function of the catalyst (see comment above), what are the consequences of a plugged vent?

48. Appendix A, Page 16 Please provide a physical description of the palladium-coated porous alumina pellets used as a catalyst in the vessel.

What is the nominal weight of catalyst added to each vessel and how was

.the adequacy of this quantity determined? Has an analytical basis for this quantity been established?

49. Appendix A, Page 22 Tne dewatering tests simulating decay heat showed small quantities of residual water. Since the SDS liners having radionuclide concentrations less than the Class C limits will have low decay heat, how will you be sure that the one percent free liquid requirements will be met? Data showing residual water with no decay heat are not presented in the report.

50. Appendix A, Page 28 It is stated that the pressure as shown on Figure 12 leveled off after an initial rise to 5 kPa. It appears from Figure 12~

that the pres ure has increased from 5.0 to 5.5 kPa (upright case) and from 4.5 to 5.8 kPa (inverted case) over the time period of 10 to 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br />. Why dc you expect that no further increase in pressure will occur past 40 hours4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br />?

51. Appendix A, Page 29 In Figure 15, the observed pressure appears to be rising over the 40 hour4.62963e-4 days <br />0.0111 hours <br />6.613757e-5 weeks <br />1.522e-5 months <br /> test. What is NUPAC's estimate for pressure increases over extended periods of time? How will these observed pressure increases affect the structural integrity of the HIC over a 300 year lifetime?

52. Appendix A, Page 39 What is the basis for the criteria limit of 100 lb of residual and bot.nd water? Demonstrate how this limit will produce less than one percent free liquids if drain tested at the disposal site.

53. Appendix A, Page 39 What is meant by "a sufficient amount of catalyst pellets will be inserted into the vessel."? How long will the catalyst 7

, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL remain effective at the highest radiolytic gas generation rate? How do you ensure that the design quantity of the catalyst is actually added?

54. Appendix A, Pages 41-45 It appears that the dewatering procedure can vary significantly in terms of the number of vacuum drying cycles and cycle length. What will be the standard procedure for dewatering the proposed liners? A copy of this procedure should be provided.

55. Appendix A, Page 46 Some SDS vessels have been shipped without recombiners. Will all of the proposed SDS liners include recombiners?

56. Appendix A, Page 51 While the residual water which collects in the bottom of the liner may not substantially affect hydrogen gas generation, it could result in unacceptable free liquid quantities. What will be done to minimize this quantity of free liquid?

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57. Appendix A, Pages 55-58 Are reports available on the referenced programs.

If so, please provide them.

58. Appendix A, Page 60 Will concrete overpacks be used for the disposal of the SDS liners at the Hanford commercial sitc? What special handling provisions will be needed?

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL The following comments and questions apply to Appendix B, " Corrosion Assessment of Submerged Demineralizer System Vessels for Burial as High-Integrity Containers at the Hanford Commercial Waste Disposal Site" (Ref. 17), which considers corrosion of the SDS vessel.

59. Appendix B, Page 2 What is the basis for the 1000 Ci maximum loading to meet 10 CFR Part 61? If only Cs-1.37 is considered, the maximum activity for 0.2 cubic meters of zeolite to meet the Class C limits is 920 C1.

60. Appendix B, Page 3 The 300 series austenitic stainless steels are thermodynamically metastable and may undergo detrimental phase changes over long periods of time (Ref. 18). In addition, weld affected material may also undergo transition to a sigma phase. Molybdenum additions, as in 316L, have been shown to increase the tendency to sigma phase formation (Ref. 19). At room temperature these changes will be occuring slowly.

However, these changes over 300 years may be significant. What effects will this metastability have on the structural integrity of the SDS liner over the 300 year design lifetime?

61. Appendix B, Page 6 It is unclear from reading Appendix A that, indeed, the free liquid content will be less than 0.5 percent by volume. See previous comments on Appendix A.

62. Appendix B, Page 7 Figure 3 of Appendix B is illegible in the copies provided to the NRC. In addition, the location of the Hanford commercial site is not shown. Please provide a legible copy of this figure with the location of the Hanford site marked.

63. Appendix B, Page 8 A considerable part of the discussion the Appendix B deals with soil types. Is this done in order to show that the Hanford soil types are non-corrosive or is something else intended? Table 2 contains a correlation table for the map of soil types. If the Hanford soils were wet, they would appear to be fairly corrosive, due largely to chloride content and resistivity.

64. Appendix B, Page 11 Figure 4 of Appendix B is illegible in the copies provided to the NRC. Please provide a legible copy of this figure.

65. Appendix B, Page 12 Should this sentence read: " .. resistivity decrease is due..." rather than: " ... resistivity increase is due..."?

66. Appendix B, Page 13 Figure 5 of Appendix B is illegible in the copies provided to the NRC. Please provide a legible copy of this figure.

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, NVPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL

67. Appendix B, Page 14 It is not clear what'the concentration of soluble ions in Table 5 is. Perhaps the factor (x 1000) in the heading is incorrect and should be omitted. Thus, the chloride concentration at the Hanford site ~ s probably 2 meg per 100 gramsjof soil. This would be higher than normal for most soils in the U.S. Please confirm this interpretation.

68. Appendix B, Page 17 As a general rule, with many exceptions, a soil is considered (Ref. xx) noncorrosive well above'5,000 ohm-cm, and not 1,000 ohm-cm as the authors state in this document. What were the other characteristics of the referenced "relatively non-corrosive soil" (pH, soluble ion concentration, moisture, etc.)?

69. Appendix B, Page 17 Is the 300 mil /300 year rate correctly calculated for 0.5 gm per square meter-day? For a small crevice, this rate seeins much greater than 300 mill /300 yr.

70. Appendix B, Page 15 What are the consequences of galvanic corrosion due to the compositional differences between the Type 316L stainless steel vessel and the Type 304 stainless steel components (nuts, bolts and fittings)? <

71. Appendix B, Page 17 'In this section of the report, it is stated " pit

• growth kinetics tend to be cubic, not ' linear." Does this mean that the mass of material removed depends on the cube of time, or that the mass of material removed depends on the cube of pitting depth (which is assumed to increase linearly with time)? Is the cubic dependency an accepted

. relationship, or simply a " tendency" as stated in the text? Is this relationship applicable to 316L stainless steel in a burial ground environment? Provide the technical information used to support the NUPAC position.

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72. Appendix B, Page 17 On this,page, it is stated that " Pit grcwth kinetics are generally governed by a cuoic rate <1aw. Crevice corrosion rates of 0.5g/m2 -day (300 mil in 300 yr) have been reported for 316SS in seawater."

If one accepts that pit growth kinetics and crevice corrosion kinetics are -

the same, these statements appear inconsistent. This problem recurs on pages 30 and 31 of Appendix B.

l l In addition, the issue of' stainless steel behavior in brine is a complex one and, if use were.to be made of arguments based on brine corrosion measurements, a range of 'cbservations should be cited. However, no use seems to be made of the argument. Is the behavior of stainless steel in seawater germane to this report?

73. Appendix B, Page 17 The. text states that " Stainless steel is also highly susceptible to pitting in stagnent, deaerated seawater." This condition l is very similar to the condition in which the high integrity container l

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL will be buried -- stagnant, poorly aerated, and in the presence of "

appreciable chloride, so it seems that the authors should conclude that

!_ the stainless steel would be highly susceptible to pitting in this proposed burial environment.

l j 74. Appendix B, Page 19 Trans' granular stress corrosion cracking (SCC) should

] also be addressed as a potential failure mechanism for the SDS vessel.

75. Appendix B, Page 20 Is the discussion on passive films applicable to the SDS liner? If so, how will the film be maintained to ensure protection -

for a 300 year period?

76. Appendix B, Pages 21-24 The basic argument in this section concerning

, underground stainless steel corrosion experience is that the data on failure of stainless steel objects at Hanford are irrelevant to the present container because of electrical isolation, differences in soil properties and placement. It is concluded that the relevant data are  ;

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contained in the NBS work. Is elimination of the Hanford data necessary j to support the conclusions of the report?

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77. Appendix B, Page 22 Ten percent of the failures were in contact with

! asphalt, which is rich in carbon. This lends some support to the question l of using graphite in the plug of the quick-disconnect valve.

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78. Appendix B, Page 24 You have concluded that specific pit penetration depths and average metal losses will occur-in soils similar to Hanford

.! . soils by referencing Tables 7 and 8. It is unclear, however, how the two i

tables were used to produce your conclusions. For example, what soils have you assumed to be similar to the Hanford soils? How were your pit penetration depths and average metal losses determined from these data?

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! 79. Appendix B, Page 27 In the section entitled "Other Underground Stainless

! Steel Corrosion Information," it is not at' all clear how the authors

arrived at the pitting value of 16 mils,- shown at the top of page 27.

I They suggest that the value was obtained from Tables 7 and 8 for "304 SS

in soils similar to Hanford sandy loam," but we could not identify the "similar soils." It is important to point out that the NBS Circular 579 pit depth data that the authors reference is a minimum pit depth where 4

there was perforation of a wall thickness of the 304 SS specimen. Thus, i the actual penetration would be much greater than the value cited. ,

, 80. Appendix B, Page 27 The authors make the statement that " Degradation of j the sensitized austenitic stainless steels was also negligible." The authors cite reference 31 which, in fact, reports a weight loss of 68 mg/sq dm and pit depths of 12 mils in eight years for sensitized 304 SS in ,

j Sagemoor Sandy Loam, and this we don't believe is negligible degradation.

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL s 81. Appendix B, Page 29 U-bend tests for stress corrosion cracking are not generally regarded to be as conservative as are slow strain ~ rate tests.

Slow strain rate data should be reported.

82 Appendix B, Page 30 The National Bureau of Standards (NBS) study (Ref. xx) cited in the NUPAC report provides stainless steel corrosion data after 14 years of exposure. These data rive been used to predict corrosion of the SDS vessel after 300 years of exposure. Please provide the details of the NUPAC calculation used to extrapolate the NBS data over the 300 years period.-

83. Appendix _B, Page 31 Please provide technical data to support the NUPAC assertica that Type 316L stainless steel will corrode less than Type 316.

84. AJ pendix B, Page 31 Please provide technical data to suppcrt the NJPAC assertion that stress corrosion cracking will not be a significant factor.

85. Appendix B, Page 31 Internal corrosion should consider the chemical composition of the wastes as determined by conservative removal estimates from process stream chemistry.

86. Appendix B, Page 31 You conclude that most of the pitting will occur in the welded regions. The welded regions will also be near toythe points of highest stress (corners and joints between the vessel heads and body).

Will there be sufficient safety margin to provide structural integrity in there regions assuming metal loss by pitting and general corrosion?

87. Appendix B, Page 31 If free liouids have drained to the bottom of the vessel the moisture content in contact with the metal may be'much higher than the soil mois,ture content. In addition, oxygen may enter the vessel since vacuum condit1cns and the integrity of the Hansen fittings cannot be ensured over several years. An internal corrosion analysis should be performed using '.1ese assumed conditions.

88. Appendix B, Paga 31 .The authors assume a pit density'of 1 pit per square foot, a pit aspect ratio of one, and uniformly deep pits, which allows them to calculate that the pits will develop'tb a depth of 200 mils in~300 years on a 375 mil wall. The authors do not describe ~any justification for this assumption, and it is not at all clear how this pit density (1 pit /sq ft),or the other associated assumptions were arrived at. If we assume 1 pit per 2 square feet, which deviates from the,ir assumption by only a factor of two, then the container will perfors e well within the 300 year tice period. The authors should justify their assumptions.

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, NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL REFERENCES

1. "SDS Liner Qualification as a High Integrity Container - Hanford Burial,"

Nuclear Packaging, Inc. (Federal Way, Washington), November 20, 1984.

2. C.J. Temus (NUPAC) letter to T. Johnson (NRC) dated November 21, 1984.

3. C.J. Temus (NUPAC) letter to J. Voglewede (NRC) dated March 19, 1985.

4. T.R. England and W.B. Wilson, "TMI-2 Decay Power: LASL Fission Product and Actinide Decay Power Calculations for the President's Commission on the Accident at Three Mile Island," Los Alamos Scientific Laboratory Informal Report LA-8041-MS, Revised.

5. D.B. Nussbaumer (NRC) letter to N.P. Kirner (State of Washington) dated November 25, 1985 and transmitting " STAFF EVALUATION REPORT related to the Topical Report covering the FL-50/EA-50 High Integrity Container manufactured by Nuclear Packaging, Inc." (NRC Docket No. WM-45).

6. Ferralium Alloy 255, Cabot Wrought Products Division Report (1983), Cabot Corporation, 1020 West Park Avenue, Kokomo, Indiana 46908.

7. N.P. Kirner (State of Washington) letter to D.A. Nussbaumer (NRC) dated December 9, 1985.

8. " Proposed HIC Structural Criteria," Revision 1 (12/85). Provided to the NRC Staff by H. Lowenberg on January 2, 1986.

9. T.L. Jungling (NRC) letter to C.J. Temus (NUPAC) dated January 30, 1986.

. 10. F.L. LaQue, Marine Corrosion: Causes and Prevention, (John Wiley & Sons, New York), 1975, p. 179.

11. T.A. Jur (Engineering Design & Testing Corporation) letter to T. Johnson (NRC) on " Corrosion of Metallic High Integrity Containers" dated June 17, 1985.

12. P. L. Piciulo, Technical Considerations for High Integrity Containers for the Disposal of Radioactive Ion-Exchange Resin Waste, Brookhaven National Laboratory Report NUREG/CR-3168 (BNL-NUREG-51649), October 1983.

13. K.J. Swyler and R.E. Barletta, Irradiation of Zeolite Ion-Exchange Media, Brookhaven National Laboratory Report NUREG/CR-2785 (BNL-NUREG-51551), May 1983.

14. H.G. Shealy (South Carolina Department of Health and Environmental Control) letter to L. Poppe (Chem-Nuclear Systems) dated June 20, 1985 and transmitting " Guide for Passive Vent Design Submittals." [This reference is provided as an enclosure to M. Tokar (NRC) letter to C.J. Temus (NUPAC) dated July 9, 1985.]

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i NUPAC SUBMERGED DEMINERALIZER SYSTEM VESSEL

15. L.B. Higginbotham (NRC) letter to Commission Licensees on " Final Waste Classification and Waste Form Technical Position Papers" and dated May 11, 1983.

16. G.J. Quinn, J.0. Henrie and J. Greenborg, Submerged Demineralizer System Vessel Shipment Report, General Public Utilities / Electric Power Research Institute /U.S. Nuclear Regulartory Commission /U.S. Department of Energy (GEND) Report GEND-035, June 1984 [ Appendix A to Reference 1 above].

17. Corrosion Assessment of Submerged Demineralizer System Vessels for Burial as High-Integrity Containers at the lanford Commercial Waste Disposal Site, Pacific Northwest Laboratory Report ,3END-INF-057, November 1984

[ Appendix 8 of Reference 1 above].

18. Meeting Notes Taken at a Seminar on Predictive Testing, January 17, 1986, Sheraton-New Orleans, Speaker: Dan McCright (LLNL) on the NNWSI (tuff)

Program. Transmitted by C.G. Interrante (NBS) letter to E. A. Wick (NRC) on " Monthly Letter Status Reports for January and February 1986 (FIN-A-4171-6)" dated March 31, 1986.

19. R.D. McCright et al., Selection of Candidate Canister Materials for High Level Nuclear Waste Containment in a Tuff Repository, Lawrence Livermore National Laboratory Report UCRL-89988, p.15, November 1983 (Preprint for National Association of Corrosion Engineers Annual Meeting, New Orleans, Louisana, April 1, 1984).

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