ML20148K725

Forwards RAI Re Mcguire Nuclear Station,Units 1 & 2,Grinell Hydraulic Pipe Supports That McGuire Purchased in Aug of 96

ML20148K725
Person / Time
Site:	Mcguire, McGuire
Issue date:	06/16/1997
From:	Nerses V NRC (Affiliation Not Assigned)
To:	Barron H DUKE POWER CO.
References
TAC-M97753, TAC-M97754, NUDOCS 9706180323
Download: ML20148K725 (5)

Text

. . . - . - - _ _ - . . = ~ _ - - - . . -- .

. . June 16,1997 4

Mr. H. B. Barron Vice President, McGuire Site i'

Duke Power Company 12700 Hagers Ferry Road Hunterville, NC 28078-8985 ,

1

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION REGARDING MCGUIRE NUCLEAR  !

STATION, UNITS 1 AND 2, GRINELL HYDPAULIC SNUBBERS l (TAC NOS. M97753 AND M97754)

Dear Mr. Barron:

I The Region 11 starf has raised an issue (see Unresolved Item URI 50-369, j 370/96-11-03 in NRC Report 50-369,370/96-11) regarding the Grinell hydraulic )

, pipe supports (snubbers) that McGuire purchased in August of 1996. The l Region II Office has requested that the Office of Nuclear Reactor Regulation (NRR) staff provide information to assist in the Region's review of this

snubber issue. In order for the NRR staff to provide the requested  !

i information, the enclosed additional information is needed from Duke Power. l We would appreciate your response by July 30, 1997, i If you have any questions regarding this request, please contact me at (301) 415-1484.

Sincerely, ORIGINAL SIGNED BY:

Victor Nerses, Senior Project Manager Project Directorate 11-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation

Docket Nos. 50-369 and 50-370 4

I

Enclosure:

As stated cc w/ encl: See next page Distribution:

Docket File VNerses GHubbard f PUBLIC HBerkow OGC PD II-2 Rdg. LBerry ACRS Ah SVarga YCli JJohnson, RII [/h;U[

CCasto, RII To rcceive a copy of this document, indicate in the box: "C" - Copy without attachment / enclosure "E" = Copy with attachment / enclosure "N" = No copy 0FFICE PM: PDI I,-2, LA:PDIIt2; D:PDIl-7,l NAME VNers(sHn' LBerry X(\/ HBeffd/

j DATE 6 // 8 /97 k /l'6 /97 (// 15 /97 / /97 / /97 / /97 DOCUMENT NAME: G:\MCGUIRE\ HCG 97753.RAI 0FFICIAL RECORD COPY l

p PDR

. . ""4 g i *, UNITED STATES NUCLEAR REGULATORY COMMISSION If WASHINGTON, D.C. 3066&4001

% ,,,,, # June 16, 1997 Mr. H. B. Barron Vice President, McGuire Site Duke Power Company 12700 Hagers Ferry Road Hunterville, NC 28078-8985

SUBJECT:

REQUEST FOR ADDITIONAL INFORMATION REGARDING MCGUIRE NUCLEAR STATION, UNITS 1 AND 2, GRINELL HYDRAULIC SNUBBERS (TAC NOS. M97753 AND M97754)

Dear Mr. Barron:

j The Region II staff has raised an issue (see Unresolved Item URI 50-369,  ;

370/96-11-03 in NRC Report 50-369,370/96-11) regarding the Grinell hydraulic pipe supports (snubbers) that McGuire purchased in August of 1996. The )

l Region 11 Office has requested that the Office of Nuclear Reactor Regulation (NRR) staff provide information to assist in the Region's review of this snubber issue. In order for the NRR staff to provide the requested information, the enclosed additional information is needed from Duke Power.

We would appreciate your response by July 30, 1997.

If you have any questions regarding this request, please contact me at (301) 415-1484. l

)

Sincerely,

)

y WMC Victor Nerses, Senior Project Manager Project Directorate 11-2 Division of Reactor Projects - I/II Office of Nuclear Reactor Regulation Docket Nos. 50-369 and 50-370

Enclosure:

As stated cc w/ encl: See next page 9

McGuire Nuclear Station Units I and 2 cc:

Mr. Paul R. Newton Ms. Karen E. Long Legal Department (PB05E) Assistant Attorney General Duke Power Company North Carolina Department of 422 South Church Street Justice Charlotte, North Carolina 28242-0001 P. O. Box 629 Raleigh, North Carolina 27602 County Manager of Mecklenburg County 720 East Fourth Street Mr. G. A. Copp Charlotte, North Carolina 28202 Licensing - EC050 Duke Power Company Michael T. Cash 526 South Church Street Regulatory Compliance Manager Charlotte, North Carolina 28242 Duke Power Company McGuire Nuclear Site Regional Administrator, Region II 12700 Hagers Ferry Road U.S. Nuclear Regulatory Commission Huntersville, North Carolina 28078 Atlanta Federal Center i

61 Forsyth Street, S.W., Suite 23T85 J. Michael McGarry, III, Esquire Atlanta, Georgia 30303 Winston and Strawn 1400 L Street, NW. Elaine Wathen, Lead REP Planner Washington, DC 20005 Division of Emergency Management 116 West Jones Street Senior Resident Inspector Raleigh, North Carolina 27603-1335 c/o U. S. Nuclear Regulatory Commission Mr. Dayne H. Brown, Director 12700 Hagers Ferry Road Division of Radiation Protection Huntersville, North Carolina 28078 North Carolina Department of Environmental Health and Natural Mr. Peter R. Harden, IV -

Resources Account Sales Manager P. O. Box 27687 Westinghouse Electric Corporation Raleigh, North Carolina 27611-7687 Power Systems Field Sales P. O. Box 7288 Charlotte, North Carolina 2824-1 Dr. John M. Barry Mecklenberg County Department of Ei.vironmental Protection 700 N. Tryon Street Charlotte, North Carolina 28202 Mr. T. Richard Puryear Owners Group (NCEMC)

Duke Power Company 4800 Concord Road York, South Carolina 29745

- - - _ ~ . - _ - ~ _ - _ . - - _ - - - - - . - - - - . _ _ - - - -

i RE00EST FOR ADDITInNAL INFORNATION

~

, MCGUIRE NUCLEAR STATION GRINELL HYDPAULIC M8BBERS

} 1. Based on the staff's review of the information provided in McGuire's Final Safety Analysis Report (FSAR), it appears that the affected

Grine11 hydraulic snubbers at McGuire do not meet their design or j

licensing basis pertinent to the design and qualification requirements i

for snubbers. General Design Criterion (GDC) 2, " Design Bases for Protection Against Natural Phenomena" of Appendix A requires, in part, that the design bases for structures, systems, and components important to safety reflect appropriate combinations of the effects of normal and accident conditions with the effects of natural phenomena such as earthquakes. Part 100 of Appendix A further requires that a suitable.

dynamic analysis or a suitable qualification test be used to demonstrate i that structure other concurren,t loads. systems, and components can withstand the seismic and In addition, GDC-4, " Environmental and Dynamic Effects Design Bases" requires that structures, systems, and components important to safety be designed to accommodate the effects of, and to be compatible with, the environmental conditions associated with normal 4

i

. operation, maintenance, testing, and postulated accident conditions.

j

McGuire FSAR Tables 3-49 and 3-50 require that all safety-related pipe

supports be designed for the concurrent dynamic loadings resulting from safe-shutdown earthquake (SSE) and pipe ruptures for the faulted 4 condition. This is consistent with the staff's position on the loading combination criteria for the pipe su) port design as described in  ;

l

Standard Review Plan 3.9.3 to meet tie above described GDCs i

requirements. McGuire's safety-related snubbers should be designed and qualified for the concurrent dynamic loadings as well as the associated environmental conditions resulting from SSE and pipe ruptures. However, it is noted that the affected Grinell hydraulic snubbers do not meet their purchased (design) specifications for environmental conditions.

i

' The temperature specification was 350*F. The temperature specification is a concern because according to FSAR Figure 6-24, the anticipated containment temperature following a postulated main steamline break 2

(MSLB) would reach approximately 315'F and the licensee states that these Grine11 snubbers will significantly deform above 250*F. Duke i

Power has not adequately demonstrated the capability of these safety-

! related snubbers to perform their design safety functions under the i

accident environments either by a qualification test or a suitable i

' analysis. Duke Power is requested to demonstrate how these Grine11 hydraulic snubbers comply with the pertinent licensing basis and the GDC requirements for design and qualification for the concurrent dynamic loadings as well as the associated environmental conditions resulting from SSE and postulated pipe ruptures. '

Enclosure

i

! 2. In its assessment of the snubbers' operability during a postulated MSLB event, the licensee relies upon a time lag between the peak dynamic load due to pipe rupture and the peak containment temperature transient for the double-ended steamline break such that the temperature peaks after the pipe rupture dynamic load is ovep. However, Figure 6-24 of the McGuire FSAR shows that for a 1.4 ft double-ended MSLB, the temperature in the lower compartment peaks at 315'F immediately after the postulated MSLB and eventually drops and steadies at about 250*F indefinitely. It is not clear how Duke Power justifies the time lag between the peak pipe rupture dynamic load transient and the peak temperature transient. Duke Power is requested to provide a detailed comparison of these two transients.

l Moreover, it is noted that in its snubber operability assessment, Duke Power only discusses the possible scenario of a postulated MSLB. No seismic effects are considered. As previously discussed in question 1,

! the licensing basis for McGuire requires that the safety-related snubbers be designed and qualified for both pipe rupture and SSE for the faulted condition. Since Duke Power indicates that these Grine11 i hydraulic snubbers will experience significant distortion at temperatures above 250*F, it is not clear how these degraded snubbers would be able to provide their design safety functions: (1) restrain the pipe for dynamic loading, and (2) allow for the free thermal movement of the pipe. Duke Power is requested to demonstrate the functionality of these snubbers under the postulated accident environmental conditions.

4