ML12227A686

Request for Exemption from Certain Requirements of 10 CFR 72.212(a)(2), 72.212(b)(5), 72.212(b)(11) and 72.214

ML12227A686
Person / Time
Site:	Oconee, 07200040, 07201004
Issue date:	08/13/2012
From:	Gillespie T Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation
References
TAC L24519
Download: ML12227A686 (13)

Text

T. PRESTON GILLESPIE, JR.

Vice President YE nergye Oconee Nuclear Station Duke Energy ON01 VP / 7800 Rochester Hwy.

Seneca, SC 29672 10 CFR 72.7 864-873-4478 864-873-4208 fax T. Giliespie@duke-energy.com August 13, 2012 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

Duke Energy Carolinas, LLC Oconee Nuclear Station, Units 1, 2, and 3 Docket Nos. 72-40, 50-269, 50-270, 50-287 Request for Exemption from Certain Requirements of 10 CFR 72.212(a)(2), 72.212(b)(5), 72.212(b)(11) and 72.214

References:

(1) NRC Certificate of Compliance for Spent Fuel Storage Casks Issued to Transnuclear, Inc., Certificate No. 1004, Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel, Amendment No. 9, Effective Date April 17, 2007.

(2) Transnuclear letter dated February 9, 2011, "Application for Amendment 13 to Standardized NUHOMS Certificate of Compliance No. 1004 for Spent Fuel Storage Casks, Revision 0."

(3) NRC letter dated February 14, 2012, to Mr. Donis Shaw, Transnuclear Licensing Manager, "First Request for Additional Information for Review of Amendment No. 13 to the Standardized NUHOMS System (TAC NO. L24519)."

Duke Energy Carolinas, LLC (Duke Energy) requests U. S. Nuclear Regulatory Commission (NRC) approval of an exemption to certain requirements of 10 CFR 72.212(a)(2), 72.212(b)(5),

72.212(b)(11) and 72.214 pursuant to 10 CFR 72.7. The regulations require, in part, compliance to the terms and conditions of the NUHOMS Certificate of Compliance (CoC) 1004 (Reference 1). The CoC conditions require the general licensee to meet the requirements of the Technical Specifications (TS) for the NUHOMS storage system (Attachment A to the CoC).

This requested exemption pertains to Technical Specification (TS) 1.2.1, "Fuel Specifications,"

and the "Zircaloy-clad" requirement in the following associated tables:

Table 1-1i, "PWR Fuel Specification for Fuel to be Stored in the Standardized NUHOMS-24PHB DSC."

Table 1-2n, "PWR Fuel Qualification Table for Zone 1..."

Table 1-2o, "PWR Fuel Qualification Table for Zone 2..."

Table 1-2p, "PWR Fuel Qualification Table for Zone 3..."

K~D1.

www. duke-energy, com P

U. S. Nuclear Regulatory Commission August 13, 2012 Page 2 A detailed discussion of this exemption request is provided in the Enclosure and Attachment to this letter. Duke Energy believes this exemption is justified and will reduce the risk of substantial exposure during loading operations of the NUHOMS storage system at Duke Energy's Oconee Nuclear Station (ONS).

Loading and storage of the NUHOMS -24PHB System under the provisions of the exemption, if approved, will be consistent with elements of a pending license amendment request submitted by Transnuclear, Inc. (Reference 2). However, based on the current NRC review schedule (Reference 3), approval of the amendment is not expected until early 2013.

Duke Energy requests NRC approval of this exemption request by December 31, 2012, to support a loading campaign from the ONS Unit 1 and 2 spent fuel pool planned to begin in early January 2013.

Please note that NRC approval of the aforementioned CoC amendment (Reference 2) would obviate the need for this exemption. However, based on discussion with the NRC Staff, it is not anticipated that the license amendment will be approved and effective in time to support Duke Energy's anticipated loading schedule; hence, this exemption is necessary.

The exemption would continue to apply to all NUHOMS -24PHB Systems loaded under CoC Amendment No. 9 (Reference 1) (up to 10 more loadings to complete Phase 6 of ONS's Independent Spent Fuel Storage Installation (ISFSI)); however, following NRC approval and subsequent implementation at ONS of Amendment No. 13 (Reference 3), the exemption would not be required for future -24PHB System loadings.

There are no regulatory commitments contained within this exemption request.

If you have any questions or require additional information, please contact Stephen C. Newman, Senior Engineer, Oconee Nuclear Station Regulatory Affairs Group, at (864) 873-4388.

Sincerely, T. P. Gillespie, Enclosure Attachment

U. S. Nuclear Regulatory Commission August 13, 2012 Page 3 xc: w/enclosure/attachment Mr. John P. Boska, Project Manager (by electronic mail only)

U. S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation 11555 Rockville Pike Rockville, MD 20852-2746 Mr. Victor M. McCree, Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 Mr. Andrew T. Sabisch NRC Senior Resident Inspector Oconee Nuclear Station Ms. Susan E. Jenkins, Manager Radioactive & Infectious Waste Management SC Dept. of Health and Environmental Control 2600 Bull St.

Columbia, SC 29201 C. Haney, Director Office of Nuclear Material Safety and Safeguards U. S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop E1D2M Rockville, MD 20852-2738 M. D. Waters, Chief - Licensing Branch Office of Nuclear Material Safety and Safeguards U. S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop E3 D2M Rockville, MD 20852-2738 Robert P. Carrion, Division of Reactor Safety U. S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257 Cecil A. Fletcher II, Division of Reactor Safety U. S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE Suite 1200 Atlanta, GA 30303-1257

Enclosure Request for Exemption from Certain Requirements of Title 10 of Code of Federal Regulations Part 72.212(a)(2), 72.212(b)(5), 72.212(b)(11) and 72.214

Enclosure - Request for Exemption August 13, 2012 Page 2

1.

Request for Exemption Duke Energy hereby requests an exemption from certain requirements of 10 CFR 72.212(a)(2), 72.212(b)(5), 72.212(b)(1 1) and 72.214 that require compliance with the terms and conditions of the NUHOMS CoC (Reference 1) (Note: "References" in this enclosure refer to Section 7.0 of this enclosure.) This exemption, if approved, would apply to all -24PHB Systems loaded under CoC No. 1004, Amendment No. 9 (up to 10 more loadings to complete Phase 6 of ONS's Independent Spent Fuel Storage Installation (ISFSI)); however, the exemption would not be required for future cask loadings following NRC approval and subsequent implementation at ONS of the license amendment proposed by Transnuclear (Reference 2).

2.

Background

The NUHOMS system provides for the horizontal, dry storage of canisterized spent fuel assemblies (SFAs) in a concrete horizontal storage module (HSM). The cask storage system components for NUHOMS consist of a reinforced concrete HSM and a dry shielded canister (DSC) containment vessel with an internal basket assembly which holds the SFAs.

The HSM is a low profile, reinforced concrete structure designed to withstand all normal condition loads as well as the abnormal condition loads created by earthquakes, tornadoes, flooding, and other natural phenomena. The HSM is also designed to withstand abnormal condition loadings postulated to occur during design basis accident conditions such as a complete loss of ventilation.

The structural features of the DSC design depend, to a large extent, on the postulated design basis transfer cask drop accident. The DSC shell, the redundant closures on each end, and the DSC internals are designed to ensure that the intended safety functions of the system are not impaired following a postulated transfer cask drop accident. The limits established for equivalent decelerations due to a postulated drop accident are intended to be bounding. They envelop a range of conditions such as the transfer cask handling operations, the type of handling equipment used, the transfer cask on-site transport route, the maximum feasible drop height and orientation, and the conditions of the impacted surface.

Each NUHOMS system model type is designated by NUHOMS-XXY. The two digits (XX) refer to the number of fuel assemblies stored in the DSC, and the character (Y) is a P for PWR, or B for BWR, to designate the type of fuel stored. A fourth character (T) is added, if applicable, to designate that the DSC is intended for transportation in a 10CFR71 approved package. The number of HSMs to be erected at any one time depends on individual plant discharge rates and storage capacity needs, and will be addressed by the licensee.

Certificate of Compliance 1004, Amendment 9 (Reference 1) conditions require the general licensee to meet the requirements of the Technical Specifications (TS) for the NUHOMS System (Attachment A to the Certificate of Compliance). TS 1.2.1, "Fuel Specifications," and following associated tables specify requirements for the fuel assemblies to be loaded in the 24PHB System's dry shielded canister (DSC):

Enclosure - Request for Exemption August 13, 2012 Page 3 Table 1-1i, "PWR Fuel Specification for Fuel to be Stored in the Standardized NUHOMS-24PHB DSC."

Table 1-2n, "PWR Fuel Qualification Table for Zone 1..."

Table 1-2o, "PWR Fuel Qualification Table for Zone 2..."

Table 1-2p, "PWR Fuel Qualification Table for Zone 3..."

Duke Energy requests an exemption from the "Zircaloy clad" verbiage requirement in TS Tables 1-1 i, 1-2n, 1-2o, and 1-2p (the actual TS Tables are shown in an Attachment to this Enclosure). This requirement, generally understood to refer to Zircaloy-2 or Zircaloy-4 cladding, precludes the storage of Babcock and Wilcox (B&W) Mark B1 1 and Mark B1i1A fuel assemblies which have M5 cladding1 (Reference 3).

In lieu of this requirement, Duke Energy is requesting to apply a more generic interpretation of the "Zircaloy clad" requirement depicted in these tables that includes the B&W M5-cladded fuel assemblies described previously.

3.

Justification for Granting the Exemptions The specific requirements for granting exemptions to 10 CFR Part 72 licensing requirements are set forth in 10 CFR 72.7, "Specific Exemptions," which states: "The Commission may, upon application by any interested person or upon its own initiative, grant such exemptions from the requirements of the regulations in this part as it determines are authorized by law and will not endanger life or property or the common defense and security and are otherwise in the public interest."

The following factors are relevant to this exemption request:

A.

The ONS ISFSI regulations cited in this exemption request, 10 CFR 72.212(a)(2),

72.212(b)(5), 72.212(b)(1 1) and 72.214, are contained within 10 CFR Part 72 of the Commission's regulations. The Commission has the legal authority to issue exemptions for the ONS ISFSI as provided in §72.7.

B.

The requested exemption items introduce no undue risk to the public health and safety. The NRC has previously considered acceptability of cladding types for spent fuel storage and determined a broader limitation is warranted. This is reflected in Interim Staff Guidance (ISG) 11, Revision 3 (Reference 4) which provides technical review guidance to materials reviewers and specifies criteria that should be met. The following statements excerpted from ISG-1 1, Revision 3 are relevant:

i. "The following acceptance criteria and review procedures are designed to provide reasonable assurance that the spent fuel is maintained in the configuration that is analyzed in the storage SARs. These criteria are applicable to all commercial spent fuel burnup levels and cladding materials [emphasis added]."

1 M5 is AREVA's proprietary variant of Zr Nb which was approved by the USNRC for PWR reactors (Reference 3).

Enclosure - Request for Exemption August 13, 2012 Page 4 ii. "The staff believes that this guidance will allow all commercial spent fuel that is currently licensed by the Nuclear Regulatory Commission (NRC) for commercial power plant operations [emphasis added] to be stored in accordance with the regulations contained in 10 CFR Part 72."

Since B&W 15x15, Mark B11 and Mark B11A fuel assembly designs are both licensed for operation in ONS's reactors with M5 cladding material, there is reasonable assurance the spent fuel will be maintained in the configuration analyzed in the NUHOMS SAR.

C.

The requested exemption is consistent with elements of a pending license amendment request submitted by Transnuclear, Inc. (Reference 2) that is currently under NRC review. In that request, the "Zircaloy clad" restriction has been deleted from the Physical Parameters sections of Table 1-1i, "PWR Fuel Specifications for Fuel to be Stored in the Standardized NUHOMS -24PHB DSC", and "Zircaloy clad" has been replaced by "zirconium alloy" in Tables 1-2n, 1-2o, and Tables 1-2p which specify cooling times for Zones 1,2, and 3, respectively.

D.

The requested exemption items are consistent with providing for the common defense and security. The ONS ISFSI will continue to be physically protected under Duke Energy's Physical Security Plan, and the exemption request does not affect the confinement of the spent fuel stored at the ISFSI facility.

E.

Duke Energy seeks this exemption from the cited Commission rules to allow loading spent fuel into the NUHOMS storage system with minimum radiological exposure to the workers during handling, preparation, and transfer operations.

Absent the ability to load Mark B1 1 and Mark B1i1A fuel designs, ONS will exhaust its current inventory of older "Zircaloy" fuel designs during the 2013 loading campaign from the ONS 1 and 2 spent fuel pool. Some of the older "zircaloy" fuel assemblies are needed for subsequent loadings after Amendment 13 is approved in order to meet the decay heat zoning requirements. If these assemblies are not available, the NUHOMS canisters will likely have to be "short-loaded" (i.e., loaded with fewer than the allowed 24 spent fuel assemblies). This, in turn, will necessitate additional NUHOMS loadings resulting in additional worker exposure.

4.

Conclusion Duke Energy concludes that the requested exemption from certain requirements of the 10 CFR 72.212(a)(2), 72.212(b)(5), 72.212(b)(11) and 72.214 regulations, allowing storage of M5 cladding associated with B&W 15x15, Mark B1 1 and Mark B11 A fuel designs, is justified. Such an exemption meets the specific exemption requirements of 10 CFR 72.7. The requested exemption item is authorized by law, will not endanger life or property, and is consistent with the common defense and security. The requested exemption is consistent with elements of a license amendment request that is currently under NRC review (Reference 2). Furthermore, granting this exemption will result in fewer additional NUHOMS loadings and reduced radiological exposure due to the

Enclosure - Request for Exemption August 13, 2012 Page 5 reduced quantity of NUHOMS storage units at the ONS Independent Spent Fuel Storage Installation.

5.

Environmental Consideration Pursuant to the provisions of 1 OCFR 72.7, Duke Energy is requesting an exemption, consisting of two elements, from certain requirements under the 10 CFR 72.212(a)(2),

72.212(b)(5), 72.212Lb)(11) and 72.214 regulations. If the proposed exemption is approved, NUHOMS canisters will not have to be "short-loaded" in future loading campaigns (i.e., loaded with fewer than the allowed 24 spent fuel assemblies). This, in turn, will result in fewer additional NUHOMS loadings and reduced radiological exposure due to the reduced quantity of NUHOMS storage units at the ONS Independent Spent Fuel Storage Installation.

Additionally, the proposed exemption does not affect the type of radioactive effluents or the quantity or type of nonradioactive effluents entering the environment.

Therefore, there is no significant environmental effect associated with the proposed exemption.

6.

Precedent Currently, other NUHOMS storage systems included in CoC No. 1004 permit storage of fuel designs with cladding other than "Zircaloy." These include the similar NUHOMS -24PTH System (Reference 1, Table 1-1i) and the NUHOMS -32PTH1 System (Reference 5, Table 1-1aa).

7.

References

1.

NRC Certificate of Compliance for Spent Fuel Storage Casks Issued to Transnuclear, Inc., Certificate No. 1004, Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel, Amendment No. 9, Effective Date April 17, 2007.

2.

Transnuclear letter dated February 9, 2011, "Application for Amendment 13 to Standardized NUHOMS Certificate of Compliance No. 1004 for Spent Fuel Storage Casks, Revision 0."

3.

NRC letter dated February 4, 2000, Revised Safety Evaluation (SE) for Topical Report BAW-10227P: "Evaluation of Advanced Cladding and Structural Material (M5) in PWR Reactor Fuel" (TAC No. M99903).

4.

Spent Fuel Project Office, Interim Staff Guidance - 11, Revision 3, "Cladding Considerations for the Transportation and Storage of Spent Fuel," dated November 17, 2003.

5.

NRC Certificate of Compliance for Spent Fuel Storage Casks Issued to Transnuclear, Inc., Certificate No. 1004, Standardized NUHOMS Horizontal Modular Storage System for Irradiated Nuclear Fuel, Amendment No. 10, Effective August 24, 2009.

Attachment Applicable sections from Technical Specifications Amendment No. 9

Attachment - Applicable TS Sections August 13, 2012 Page 2 Table 1-1i PWR Fuel Specilleation lorFuel to be Stored in the Standardized NUMlOMSO-24P]-B DSC Title or Parameter Specifications Fuel Only intact, unconsolidated B&W 15x 15 (with or without BPRAs), WE 17x17, WE 15x15, CE 14x 14, and WE 14x14 (all without BPRAs)

Class PWR fLuel assemblies or cquivalctin reload fuel manufactured by other voedor, with the following "eairuiemcnts Maximum No. of Rwconstituted Assemblies per 4

DSC with Stainlcss Steel rotk Maximum No, of Stainles Steel Rods per 10 Reconstituted As.sembly Maximumn No. of Reconstituted Assemblies per 24 DSC with low enriched uraniutm oxide rods Physical Parameters (without, BPRAs)

Maximum Assembly length (utuirradiatcd) 165.785 in (standard cavity) 171.96 in (long cavity)

Nominal Cros-Sectional Envelopc 8.536 in Maximum Assembly Weight 1682 lbs No. of Assemblies per DSC intact Tas.

cs Fuel Cladding Zircaloy-cM fuel th no known or suspectd Physical Parameters (wilh RPRAi)

MaximumAssembly + RPRA Length (unin'adiated) 17t.96 in (long cavity)

Nominal Cross-Sectional Envelope 8.536 in Maximum Assembly + BPRA Weight 1682 lbs No. of Assenmblies per DSC

• 24 intact assl js No. or 13PRAs per' DSC u aZirca]oy-clad ruel viLh no kjiown or suspected Nuclear Parameters Maximumn Fuel Initial Enrichment 4.5 w%. % U-235 Maximum Initial Uranium loading per assembly 0.490 MTU Allowable loading configurations for cacti 24PHB As specified in Figure 1-8 or 1-9 DSC "Burnup, Enrichment, and Minimum CGuAing Time Table 1-2n for Zone I fuel; Table 1-2o for Zoae For Configuration I (Filgire 1-8) 2 fuel; Table I -2p for Zone 3 fuel 13urnup. Enrichment, and MinituLeM Cooling Trime Table 1-21) fOr Zone 3 fuel far Configuration 2 (Figure 1-9)

Minimum Cooling Time ifor BPRAs 5 years Total Decay Heat per DSC 24 kW

_ Dccay Heat Limits fbor Zone I, 2 and 3 ful As specified in Fiiies 1-8.tnd 1-9.

A-17

Attachment - Applicable TS Sections August 13, 2012 Page 3 Table l-2n PWR Fuel Qualification Table for Zone I with 0.7 kW per Assembly, Fuel With or Without BPRAs, for the N IlMOMSO-24PRB DSC (Mininuam rrequid ycars of cooling time after reactor car dischiarc)

• BU A-cnt average Iuiz 5ý 57-0 toUse bu 1.up 0d e15.h0 nn to tone-mSAm s

1 1

• 0oi time in yc

a. For f5.0a ascblics reoo.tiwtcd wih up

5.

10 15an.,0a.0e 5-0 5

1y, if5 5

lookuj5 eoOir4 tine is es t n P.O years then amirtmur cooling tit,,

1f 9.0 yS.0 1a5.l beS'D aed 5cee5c0 iS re0po sbl, (or 15.0ing d3.0 E0d13ttltt t6 5

fuetl ewriclh.rcn axed harmap are¢ ecn'aeti eceano'ed fbr duin8 fur qualification Rosesti buwup UP to cast highecr watry. roim~d c rhanent DOWVN to nasi lower enny.

Fuci wiah an initial enrihment gecate than 4,5 W-56 U1-235 is um~ceptble for storage.

2 runt w ith a b1i3up 1.0lea 5.n 50 1W5'M T-U is e.p0.b *.0 To r

ý.

Tao tl155 5.ye s coo.in0.

2 0pT o o 1An7 6-5s6y.wil 63 sinit r5ia3

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l5bupof465GW I isac tb tr s iea195i time as de'fined by 3.7 ",a. % 11-235 (waai*don w 47 Ci Wd/MTU (r'ounding irp) Oat ibe qualifirctautblel,[¢

• SCCFigUeI-8for adC eC1ptiOp%%

• For asse. blihs ful reorsn r~wth imal*castmian de rod use tie uaae'tby az'erms"m cluiitmelmz to daetmere.l die mzinimu~m rorli~ig ime.

A-47

Attachment - Applicable TS Sections August 13, 2012 Page 4 Table 1-2o PWR Fuel Qualification Table for Zone 2 with 1.0 kON per Assembly, Fuel With or Without BPR,%s, for the NUHOMSe-24PUB DSC (Mhmhuum required years of couling time after reactor core discharge) 30 34 36 33 39 40 4 1 412 435

'4 45 46

-0 52 33

-;1-

33. u 3.16 iii! ii.

3.1 j

33. 33.0 Mk 2,; 32J 22 BILY

- Assembly aversoec buffmV Use bumrup =rd eotrichment to tookp gn~isrmur cooling time in ymnxs For fueel assembiLes teeonstfljted o.itŽ, up to 10 stalkless steel rods only, if tle tookx, eso!in~ time is Ims thata 9. )ers d=a a mir~irnu coalino time oC9.0yews sh~ll be used.LkneisrsibeCtnuts toueesiie mn fitel cailunent and btmnt It w neortecyaeroototed for during fuel quaifiatin.

momd bttmvp UPre =eus tught; entry. tiound =

hricvinti DOWN to next lower entry.

F uel With an, inhial ennk.amurien2 pester thbsn 44 wi% IJ-235 is unsocceptable for storaec, f uel with a burtwp less than 10 GVd NTU is aceptn~e for sorsnt after 5-yenrs cooling.

• Enrrzpis An assembly with an initial erchsemient or3.75 wi. % 11.235 and a bump~ of 46. GW8JVMTUJi it sptablz for stossge aflte a 8-years cooline. tirrc as defined by 3.,7 %st. % MA g j own) and 47 GI6d/MTIJ (rourslintgup) on tho qualificasion :.ble.

• See Figurc 13.8 for a dLesoript, nrese.

• For asgarnblies vool 7 d It Zirao~y clad u olaxide rods use the assembly averag entidiment to &eteriniar te lbs inimumin o"Unolinw te A-43

Attachment - Applicable TS Sections August 13, 2012 Page 5 Table I-2p PWR Fuel Qualification Table for Zone 3 with 1.3 kW per Assembly, Fuel With or Without BPRAs, for the NUHOMS'-24PHB DSC (Minimum required years of cooling time after reactor core discharge)

B Assembly lssm l-235 Ea rchme

(%!.

• 4Isa bi. nt0

12.

d 12.i2 oen to1.

loo.4 2

ii$ sr 12.6in al7-7 i-n y.e33.

Fo te ase ble 1e13ta3tit3.ed3wish.7p3to 139 40 stines stee r4d3 ny iA rise locku 1con tc is Ice tha 9.0 5e0 he0 5.m 15.t 15of 9.0 y i o 0J 5. 5.o iA 50 50.q

.. 0 50 Is.

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S10 5

5.0 Re.e 5p UP to no 5h0 nry 15.r 1en.Oihmn 5.0 1to 5.e loe entry 1 30

5.

5.0 15.0 1I.0 3.0 A 10 50 50 5.0 1I. S A. 5.

34~~~

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42 6,)

6 601 A 10 6.0 16.0 16i.0 6.0

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• .s F uel p

wiha nta enriehanent[ igreases slim :,eain 45w.

-35 tis unacceptabl For u] storag ie. e~~~llc rt pt Osanesselrd ny £l Fuel with a bs-nup less than, I) CrGWd/*I'Ut is naceepable far storage a.fter S-years coo~ling, Example:.An sacet~bly wi*th ran infitial enuichnaeni of 3.75 wt. % U-235 aad a basausp of 4-6.5 GiWdA4TU i:s acceptable fo~r storage* after a 6.2 yeats cooling stiae as de-fined by 3,7 nt,% VsUj5 igdowar) arid 47 CrWdIMMTU (rmsad~in; u*p) on the qualification table.

45See Fig6.0e 6-.

a0d 1.9 for a*

1&0d6.016.

of zones.

• For fuel assemblies recansi~,~~Ycasatia.

ide coda* use the assembly average eru.efi,_.rit to dletrmnine she rainim,.un coolinig tins..

A-44