LIC-15-0002, Response to NRC Request for Additional Information Regarding License Amendment Request (LAR) 14-04,l Request to Adopt ASME Code, Section III, 1980 Edition (No Addenda) as an Alternative Current Code of Record

Response to NRC Request for Additional Information Regarding License Amendment Request (LAR) 14-04,l Request to Adopt ASME Code,Section III, 1980 Edition (No Addenda) as an Alternative Current Code of Record

ML15009A319
Person / Time
Site:	Fort Calhoun
Issue date:	01/09/2015
From:	Cortopassi L Omaha Public Power District
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LIC-15-0002, TAC MF4160
Download: ML15009A319 (15)

Text

-~.:..

jjjjjjjj Omaha Public Power Dislricl 444 South 16h Street Mall Omaha, NE 68102-2247 LIC-15-0002 January 9, 2015 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Fort Calhoun Station, Unit No. 1 Renewed Facility Operating License No. DPR-40 NRC Docket No. 50-285

Subject:

OPPD Response to NRC Request for Additional Information Regarding License Amendment Request (LAR) 14-04, Request to Adopt ASME Code, Section Ill, 1980 Edition (No Addenda) as an Alternative to Current Code of Record (TAC No.

MF4160)

References:

1. Letter from OPPD (L. P. Cortopassi) to NRC (Document Control Desk),

"License Amendment Request (LAR) 14-04, Revise Current Licensing Basis to Adopt American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV) Code, Section Ill, 1980 Edition, (no Addenda) as an Alternative to Current Code of Record," dated May 16, 2014 (LIC-14-0043)

(Ml 14143A370)

2. Letter from NRC (C. F. Lyon) to OPPD (L. P. Cortopassi), "Fort Calhoun Station, Unit No.1- Request for Additional Information RE: License Amendment Request to Adopt ASME Code, Section Ill, 1980 Edition (No Addenda) as an Alternative to Current Code of Record (TAC No. MF4160),"

dated September 24, 2014 (NRC-14-011 0) (ML14259A365)

This letter is responding to the Reference 2, NRC request for additional information (RAI) regarding License Amendment Request (LAR) 14-04 (Reference 1). LAR 14-04 proposes to revise the Updated Safety Analysis Report (USAR) to allow pipe stress analysis of non-reactor coolant system safety-related piping to be performed in accordance with the ASME BPV Code, Section Ill 1980 Edition (no Addenda) as an alternative to the current Code of Record.

The Omaha Public Power District's (OPPD) response is attached.

This letter contains no regulatory commitments.

Employment with Equal Opportunity

U.S. Nuclear Regulatory Commission Ll C-15-0002 Page2 If you should have any questions regarding this submittal or require additional information, please contact Mr. Bill R. Hansher, Principal Regulatory Engineer, at 402-533-6894.

Re~

Louis P. Cortopassi Site Vice President and CNO LPC/CTH/mle Attachments: 1. OPPD Response to NRC Request for Additional Information Regarding License Amendment Request (LAR) 14-04

2. USAR Markup Pages

3. USAR Clean Pages

4. Final Safety Analysis Report (FSAR), Page F-4

LIC-15-0002 Page 1 OPPD Response to NRC Request for Additional Information Regarding License Amendment Request (LAR) 14-04:

Revise Current Licensing Basis to Adopt American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV)

Code, Section Ill, 1980 Edition, (no Addenda) as Alternative to Current Code of Record

L1 C-15-0002 Page2 REQUEST FOR ADDITIONAL INFORMATION OMAHA PUBLIC POWER DISTRICT FORT CALHOUN STATION, UNIT NO. 1 DOCKET NO. SQ-285 By letter dated May 16, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14143A370) Omaha Public Power District submitted a license amendment request to revise the current licensing basis to adopt the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section Ill, 1980 Edition, (no Addenda) as an alternative to the current code of record.

The NRC staff has reviewed the information provided in your application and determined that the additional information below is required in order to complete its formal review.

NRC Question

1. The application proposed to revise Appendix F by adding NOTES (e) and (f). NOTE (e) provided the loading combinations for the piping. The earthquake and fluid transient loadings are added for combination 2 of Table F-1 in the updated safety analysis report (USAR). However, the proposed NOTE (e) for Table F-1 of the USAR states that earthquake and fluid transient loading are combined with Square-Root-of-the-Sum-of-the-Squares method. Please explain the inconsistency between Table F-1 and its NOTE (e).

OPPD Response In April 1993, OPPD received an NRC Safety Evaluation Report (SEA) for Alternate Seismic Criteria and Methodologies (ASCM) (Reference 1). The SEA states that stresses and reactions from loss-of-coolant accident (LOCA) or water hammer/steam hammer loading (e.g., rapid valve closure or opening) are combined with seismic inertial stresses and reactions by the Square-Root-of-the-Sum-of-the-Squares (SASS) method. This is consistent with the recommendations given in NUREG-1061 (Reference 2), and NUREG-0484 (Reference 3).

However, after receiving the ASCM SEA, OPPD did not revise the USAR regarding the combination of loads using SASS for piping. The SASS method of combining the subject loads will be added as an option for the load combinations in proposed NOTE (e) of USAR Table F-1 as well as the existing load combinations in Table F-1 proper. Markup and clean versions of the change are attached and supersede the USAR Table F-1 pages submitted in OPPD's license amendment request to resolve the inconsistency between Table F-1 and NOTE (e).

NRC Question

2. The service level C of NOTE (e) refers to NOTE (d), which states that these load cases and limits apply only to the pressurizer relief valve piping and supports. The staff notes that the fluid transient loadings for Class 2 and 3 piping are not limited only to the pressurizer relief valve. For example, main steam lines have relief valves, and a fast valve open and closure event, such as reactor vessel head vent valve opening, may cause hydrodynamic loading. Please explain why the load combination in the

Ll C-15-0002 Page3 proposed USAR does not address all of those loadings for Class 2 and 3 piping and supports.

OPPD Response The wording"+ (Fluid Transient Loadings (d))", accompanied by NOTE (d), was originally added to Table F-1 of the USAR by Modification FC-88-111 (Reference 4) and was not part of the original Final Safety Analysis Report (FSAR). This wording was then carried over to service level C of proposed NOTE (e) in the USAR mark-up for consistency. As discussed below, the subject wording and its note were not intended to suggest that fluid transients are only applicable to pressurizer relief valve piping and supports.

Modification FC-88-111 was required because it was determined that the pressurizer relief piping and supports had to be designed to withstand simultaneous actuation of the pressurizer power operated relief valves (PORVs) and both safety relief valves (SRVs). In the original design and analysis of the piping, transients induced by the pressurizer PORV actuation and the individual actuation of the two SRVs were considered. This is because simultaneous actuation of the SRVs was not considered probable, as the set pressures of the SRVs are different. At the time of the modification, the loading from simultaneous actuation of all four valves was considered to be beyond the scope of normal operational loads. Therefore the wording and note were added to USAR Table F-1.

Another significant contributor to the addition of subject wording and NOTE (d) by Modification FC-88-111 was the fact that some of the associated pipe support anchor bolts did not meet a design safety factor of 4 with the increased transient loads. An additional note was added to USAR Table F-1 to allow a safety factor of 2 or greater for these bolts. This reduction in the design safety factor is being evaluated in the corrective action program, which will ensure that steps are taken to disposition it appropriately.

In addition to the information provided in the USAR and Modification FC-88-111, FCS Procedure CC-FC-309-1011-AD-MSS-11, "Design Specification for Piping and Pipe Supports" indicates that dynamic effects, as applicable to specific operating and accident conditions, must be considered in the design of piping and components. Per CC-FC-309-1 011-AD-MSS-11, dynamic effects include fluid transients as well as considerations for impact, vibration, and wind.

In addition to dynamic effects, CC-FC-309-1 011-AD-MSS-11 also indicates that pressure relief valve discharge loading is to be considered where applicable.

In conclusion, the proposed USAR mark-up does address all applicable loadings for piping and supports. The"+ (Fluid Transient Loadings (d))" wording and subsequent NOTE (d) discussed in the question were added to the USAR by Modification FC-88-111 for a specific case. These additions are currently under review as part of the FCS corrective action program.

NRC Question

3. The proposed NOTE (f) states that support analysis will continue to be performed in accordance with the existing licensing basis (i.e., Seventh Edition of AISC, American Institute of Steel Construction). Please provide documentation for the existing licensing basis.

L1 C-15-0002 Page4 OPPO Response The applicable piping codes for original design and licensing of the station were United States of America Standards (USAS) B31.7, 1968 Draft Edition and USAS B31.1, 1967 Edition as noted in Appendix F of both the FSAR and the USAR. These codes state that supplementary steel shall be designed in accordance with the standards prescribed by the American Institute of Steel Construction (AISC) or the equivalent. The original licensing documents, such as the FSAR, and the original contracts to design and build the facility do not specify an edition of the AISC code used for evaluating pipe supports. Rather, the contracts state that the latest issue of the AISC code shall be used. The 71tt edition of the code was used as it was included in the 1969 AISC specification.

In addition, by letter dated April 21, 1980 (Reference 5), OPPD informed the NRC that the 71tt edition of AISC's Manual of Steel Construction would be used in evaluating supplementary steel of pipe supports. OPPD's letter was in response to Bulletin 79-02, (Reference 6), and Bulletin 79-14, (Reference 7).

NRC Question

4. Table F-1 of the USAR lists primary stress limits which cannot be found in the reference standards for both piping and vessel. The primary stress limit for the loading combination 2 expression (PB < 1.5 [1-(PM)2/SO] SO) does not appear to be correct. For example, PB would be less than a negative value with PM =20ksi and SO

=60ksi. Please provide justification for the expressions for primary stress limits for both piping and vessel in USAR Table F-1.

OPPO Response The expressions in USAR Appendix F, Table F-1 for the piping and vessel primary stress limits were approved as part of the original operating license for Fort Calhoun Station and remain unchanged from their original form in the FSAR. Table F-1 was developed from the design loading and stress criteria of the reactor coolant system (RCS) shown in USAR Section 4.2, Table 4.2-3, "Loading Combinations and Primary Stress Limits." The primary stress limit expressions are the same in the two tables with one exception. For the Loading Combination 1 piping primary stress limits, the values for Sh in the expressions are obtained from different codes. Sh is the allowable stress for a particular piping material and is tabulated for the maximum operating temperature of the piping being analyzed. In Table 4.2-3, Sh is tabulated from USAS B31.1 because it is the design code of record for the RCS. For Table F-1, Sh is tabulated from USAS B31.7 because it is the design code of record for many of the other Seismic Class I piping systems.

In addition, the Load Combination 2 primary bending stress limit equation for vessels was specifically reviewed because it is referenced in the question. The equation shown in USAR Table F-1 is the same as the one provided in the FSAR (Attachment 4) and thus is correct.

However, as the FSAR was developed before word processing software was in widespread use, the equation as typed in the FSAR and carried through to the USAR could be misapplied. The parentheses are intended to enclose both the PM and S0 terms as shown in Attachments 2 and

3. Similarly, as shown in Attachments 2 and 3, the parentheses in the Load Combination 2 primary bending stress limit equation for piping should enclose both the !!: x PM terms to be 2 s0 consistent with the FSAA.

LIC-15-0002 Page 5 These same formatting discrepancies are also applicable for the Load Combination 3 vessel and piping primary bending stress limits in Table F-1 as well as the same equations in Table 4.2-3. These formatting discrepancies are corrected in Attachments 2 and 3 to reflect the original equation found in the FSAR.

When the PM=20ksi and So=60ksi values from the text of question 4 are applied to the correct equation, the following is the result. This primary bending stress limit is positive and reasonable given the assumed values for PM and S0 .

2 20 ksi) ]

P8 :5 1.5 [1 - ( ksi 60 ksi 60 P8 :5 80 ksi Although not attached, following NRC approval, upon implementation of the requested Amendment, OPPD will make similar changes to USAR Section 4.2 to align Table 4.2-3 with Table F-1.

References

1. Letter from NRC (S. Bloom) to OPPD (T. L. Patterson), "Safety Evaluation of Alternate Seismic Criteria and Methodologies- Fort Calhoun Station (TAC No. M71408)," dated April 16, 1993 (NRC-93-0150)

2. NUREG-1061, Volume 4, "Evaluation of other Dynamic Loads and Load Combinations,"

December 1984

3. NUREG-0484, "Methodology for Combining Dynamic Responses," Revision 1, May 1980

4. Modification FC-88-111, Rev. 0, "Pressurizer Safety Valve Pipe Supports" (EC 10916)

5. Letter from OPPD (W. C. Jones) to NRC (Document Control Desk) "Completion of the Requirements of Bulletins 79-02 and 79-14," dated April 21, 1980 (LIC-80-0042)

6.Bulletin 79-02, "Pipe Support Base Plate Designs Using Concrete Expansion Anchor Bolts,"

dated March 8, 1979

7.Bulletin 79-14, "Seismic Analysis for As-Built Safety-Related Piping Systems," dated April17, 1979

LIC-15-0002 Page 1 USAR Markup Pages

USAR-Appendix F Information Use Page 9 of 40 Classification of Structures and Rev. 10 Equipment and Seismic Criteria Table F Loading Combinations and Primary Stress Limits Primarv Stress Limits Loading Combinations Vessels Piping Supports

1. Design Loading + PM<SM PM .s 1.2Sh Working Design Earthquake Stress Ps + PL .s 1.SSM Ps + PM .s 1.2Sh Anchor Bolts F.S.~4.0 (d)

2. Normal Operating PM .s So PM .s So Within Loadings ximum Yield Hypothetical Earthquake p8 ~ 1.5 [1- (~:r]so P8 4

~ -5 rr 0 cos (rr-2 X- PM) s0 Anchor Bolts

+(Fluid Transient F.S.~ 2.0 (d)

Lo~

(d )!sill (b) (c)

3. Normal Operating PM .s SL PM .s SL Deflection of supports Loadings~pe limited to 2

Rupture + Maximum ~ P8 ~ 1.5 [1- (:~) ] SL P8 ~ -4 SL 7r cos (Tr-2 PM)

X -

SL maintain supported Hypothetical Earthquak equipment within (b) (a), (c) limits shown

USAR-Appendix F Information Use Page 10 of 40 Classification of Structures and Rev. 10 Equipment and Seismic Criteria Table F-1 -Loading Combinations and Primary Stress Limits (Continued)

NOTES:

(a) These stress criteria are not applied to a piping run within which a pipe break is considered to have occurred.

(b) Loading combinations 2 and 3, stress limits for vessels, are also used in evaluating the effects of local loads imposed on vessels and/or piping, with the symbol PM changed to PL.

(c) The tabulated limits for piping are based on a minimum "shape factor". These limits are modified to incorporate the shape factor of the particular piping being analyzed.

(d) These load cases and limits apply only to the Pressurizer relief valve piping and supports.

(e) As an alternative to USAS 831.7. 1968. non-RCS. safety-related piping analvsis may also be performed in accordance with ASME Ill. 1980 Edition lno Addenda). Material properties shall be from the original code of record (i.e .. USAS 831.7. 1968). Associated stress limits shall be in accordance with ASME Ill. 1980 Edition (no Addenda) for Service Levels as shown below:

Load Combination Service Level A lEan. 8): DeadWeiaht Service Level A lEan. 1m: Thermal Service LeveLAlEan~ 11 ):_Normal Loadina: Dead_Weiahtt Thermal Service Level B: Normal + Desian Earthauake Service Level C* Normal + (Maximum Hypothetical Earthquake + (fluid Transient Loading ldU lgll Service Level D* Normal + (Maximum HYPothetical Earthquake + Pipe Rupture lgU (f) Support analysis will continue to be performed in accordance with the existing licensing basis (i.e .. Seventh Edition.

AISC, American Institute of Steel Construction).

(g) Square-Root-Sum-of-the-Squares may be used to combine loads.

UC-15-0002 Page 1 USAR Clean Pages

USAR-Appendix F Information Use Page 9 of 40 Classification of Structures and Rev. 10 Equipment and Seismic Criteria Table F Loading Combinations and Primary Stress Limits Primarv Stress Limits Loading Combinations Vessels Piping Supports

1. Design Loading + PM SSM PM< 1.2Sh Working Design Earthquake Stress Ps + PL s 1.5SM Ps + PM s 1.2Sh Anchor Bolts F.S.~4.0 (d)

2. Normal Operating PMsSo PM< So Within Loadings + (Maximum Yield Hypothetical Earthquake Pa ~ 1.s [1- G:r] so P8 ~~So cos(~ x rr 2 PM) s0 Anchor Bolts

+(Fluid Transient F.S.~ 2.0 (d)

Loadings (d))(g)) (b) (c)

3. Normal Operating PMSSL PMSSL Deflection of supports Loadings + (Pipe limited to

~ 1.5 [1- (::)

2 Rupture + Maximum Pa ] SL PB ~ !.sL cos(~ x PM) maintain supported 1l 2 SL Hypothetical Earthquake(g)) equipment within (b) (a), (c) limits shown

USAR-Appendix F Information Use Page 10 of 40 Classification of Structures and Rev. 10 Equipment and Seismic Criteria Table F-1 -Loading Combinations and Primary Stress Limits (Continued)

NOTES:

(a) These stress criteria are not applied to a piping run within which a pipe break is considered to have occurred.

(b) Loading combinations 2 and 3, stress limits for vessels, are also used in evaluating the effects of local loads imposed on vessels and/or piping, with the symbol PM changed to PL.

(c) The tabulated limits for piping are based on a minimum "shape factor". These limits are modified to incorporate the shape factor of the particular piping being analyzed.

(d) These load cases and limits apply only to the Pressurizer relief valve piping and supports.

(e) As an alternative to USAS 831.7, 1968, non-RCS, safety-related piping analysis may also be performed in accordance with ASME Ill, 1980 Edition (no Addenda). Material properties shall be from the original code of record (i.e., USAS 831.7, 1968). Associated stress limits shall be in accordance with ASME Ill, 1980 Edition (no Addenda) for Service Levels as shown below:

Load Combination Service Level A (Eqn. 8): Dead Weight Service Level A (Eqn. 10): Thermal Service Level A (Eqn. 11 ): Normal Loading: Dead Weight+ Thermal Service Level B: Normal + Design Earthquake Service Level C: Normal+ (Maximum Hypothetical Earthquake+ (Fluid Transient Loading (d)) (g))

Service Level D: Normal + (Maximum Hypothetical Earthquake + Pipe Rupture (g))

(f) Support analysis will continue to be performed in accordance with the existing licensing basis (i.e., Seventh Edition, AISC, American Institute of Steel Construction).

(g) Square-Root-Sum-of-the-Squares may be used to combine loads.

LIC-15-0002 Page 1 Final Safety Analysis Report (FSAR)

Page F-4

- .*e e -- .* e e e TABLE F-1 LOADING COMBINATIONS AND PRH1ARY STRESS LUUTS I

~ad_:_ng Combinations Primary Stress Limits Vessels Piping Supports

---

1

< < i

!1.

I Design Loading +

Design Earthquake PM - St-1 PM - 1.2Sh Working Stress I <

! PB + P L - 1. 5SM PB + PN S 1.2Sh I  :

< i Prvt - So Pr-f ~ SD 1 I

~ 1.5 [1-(~:} 2) SD I

! 2. Normal Operating Loadings < n PM I Within

+ !*laximum Hypothetical Earthquake PB PB - ~

n s0 Cos (- * --}

2 SD Yield "z;J  :

I (b) (c)

,f:-

I *-

i

I I,3. Normal Operatine Loadings Deflection of supports PM - SL PM - SL i Pa ~ 1.5 [1-(::} 2] SL

+ Pipe Rupture + Maximum < n PM limited to maintain I Hypothetical Earthquake PB - ~ s Cos (_

• c-) supported equipment 1

' 11 2 VL  !' vithin limits shown 1

i! . (b) (a),(c) *

- --- ~------ _____! _____ - ---- - - -- --- -~ - -----

Notes:

(a) These stress criteria are not applied to a piping run \-t:i.thin uhich a pipe brcalt is conside1*ed to have occurred.

(b) Loading combinations 2 and 3 >> stress limits for vesse:ls, are also used. in evaJ.uf1.t.ing the effects of local loads imposed on vessels Md/or piping~ v:i.th the symbol PM changed to P .

1 (c) The tabulated limits -ror piping ere based on a minillmo: "shr:..p :-* fl:'.ctor". These limjts r::1.' e modified to incorporate the shape factc.r of the portic:vlar pip:i.n[!: bein(*; e.nr.J.yzed.