ML19253A684

Responds to IE Bulletin 79-02,Revision 1.Discusses Review of Supports in Diesel Generator Sys,Emergency Feedwater Sys & Emergency Cooling Tower

ML19253A684
Person / Time
Site:	Peach Bottom
Issue date:	08/07/1979
From:	Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
NUDOCS 7909100667
Download: ML19253A684 (5)

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PHILADELPHI A ELECTRIC COM PANY 2301 M A R K ET STR FET P.O. DOX 8699 PHILADELPHI A. PA.19101 SHIELDS L. DALTRO FF ELacimic Pao c loM August 7, 1979 Docket Nos.: 50-277 50-278 IE Bulletin 79-02 Supplement Mr. Boyce H. Grier, Director Office of Inspection & Enforcement Region I U.S. Nuclear Regulatory Commission 631 Park Avenue Xing of Prussia, PA 19406

Dear Mr. Grier:

This is in response to your immediate action letter of August 3, 1979 and the telephone conversation between D. Marano, PECo and yout Messrs. E. Jordan and H. Wong, NRC, also on August 3, 1979 regarding the base plate and anchor bolt analysis and testing results obtained from the Peach Bottom Atomic Power Station, Units 2 and 3, pursuant to IE Bulletin No. 79-02, Revision 1. The actions requested and our responses are listed sequentially below:

Item 1, Provide a statement of the calculated factors of safety for the eight affected supports in the Diesel Generator system and a statement of system operability.

Response

In the Diesel Generator Building the calculated safety factors for the eight affected supports are as follows:

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Mr. Boyce H. Grier, Director Page 2 Hanger Support Designation Safety Factor 33 HB -

F SA >5 33 HB -F 5B >5 33 HB - F SC >5 33 HB - F SD >5 33 HB -

S 16 3.5 33 HB -

S 19 3.5 33 HB -

S 20 27 33 HB -S 21* 2.75

• Rework of support hanger 33 HB S 21 was completed as of August 5, 1979.

Since the Safety Factors of the above hangers are greater than 2.0, the affected systems are considered operable.

Item 2 For the Emergency Service Water (ESW) System, the affected support will be repaired within three days of the meeting date and to prevent possible flooding of equipment in the interim the valve in the vicinity of the support will be maintained locked closed and the pump room door kept open.

Response

The affected support, 33 HB S 158, has been reworked and the rework completed as of August 5, 1979. During the interim period, valve 33-521 located near the support was maintained locked closed and the reactor building cooling water heat exchanger coom door was left open to preclude flooding due to a line break.

Since the calculated factor of safety for the support, as built is 4.88, which exceeds the safety factor of 4 recommended in IE Bulletin 79-02, our corrective action on this support is complete. The affected system is considered operable. At completion of the work, the room was closed off. Valve 33-521 is maintained closed.

Item 3 The affected support in the Emergency Cooling Tower will be repaired within the seven day time period allowed by the Technical Specifications that began at noon August 1, 1979.

Response -

Support 48 GB S 21 was reworked to achieve a safety factor greater than 2.0 as of August 5, 1979 and with additional work

Mr. Boyce H. Grier, Director Page 3 completed August 6, 1979 now has a calculated Safety Factor of greater than 5.

With the calculated Safety Factor for the affected support in the reworked condition greater than 5, the affected system is considered operable.

Item 4 For the affected support in the Condensate Stornge System perform an evaluation for the support factor of safety using the as-built conditions, inspect and test the anchor bolts in the support and p rovide a conclusion of system operability.

Response

Support 3 HCR - S28A has been re-analyzed in its as built condition with a resulting Safety Factor of 2.1. This support was inspected and its anchor bolts tested satisfactorily.

Since the Factor of Safety of the support in its as built configuration is greater than 2, the affected system is considered operable.

Item 5 Provide an expedited testing schedu.le for anchor bolts sufficient to support statements on system operability for each unit.

Response

The following testing schedule is being implemented to achieve completion of testing and work of the Unit 2 supports by November 1, 1979 and the Unit 3 supports by October 12, 1979:

Unit 2. 572 pipe support base plates remain to be inspected, tested and accepted. An inspection, testing and acceptance rate of approximately forty-five places per week over the next thirteen weeks has been established.

Unit 3. 490 pipe support base plates remain to be inspected, tested and accepted. To coincide with the completion of the Unit 3 outage, completion of the inspection, testing and acceptance of the Unit 3 affected base plates is scheduled for October 12, 1979. Therefore, a testing and acceptance rate of approximately 50 base plates per week for the next ten weeks has been established. n -' x O*t',~l2 va Testing and acceptance of pipe support base plates will be monitored on a system basis as information is received to ensure that all Seismic Category I Systems are tested and accepted in a timely manner and to monit or p otential trends.

Mr. Boyce H. Grier, Director Page %

Item Description of the disposition of other pipe supports with safety factors less than 2 which were identified in PECo response to IE Bulletin 79-02 and subsequent discussions with NRC representatives.

Response

The Safety Factors of the remaining supports identified in previous correspondence and discussions after rework and/or re-analysis are as follows:

Support No Safety Factor 3-10GB-S44 >5.0 3-23DDN-S26 2.14 23DDN-S31 2.6 3-9HB-SI 2.24 10GB-S44 2.83 3-33HB-S126 >5.0 33HB-S148 >5.0 -

33HB-S157 >5.0 3-10GB-H86 2.66 48GB-S19 3.09 48HB-S18 3.09 3-23DDN-H17 4.34 23DDN-H17 4.83 3-23HB-H106 >5.0 Sin e the above listed Safety Factors are greater than 2, the arfected systems are considered operable.

Pipe support 3-10GB-H58 is a spring hanger and as agreed need not be reworked at this time; however, this support will be upgraded during the next Unit 3 outage, s che duled t o b e completed by October 12, 1979.

Note that the first eight hanger supports listed above are the eight supports identified in our response to IE Bulletin 79-02, Item 2 as having factors of safety less than 1.0.

Also in our response to IE Bulletin 79-C2, Item 2 we identified 13 supports with factors of safety less than 2 but greater than

1. Subsequently, it was determined that one of the supports identified was not Seismic Category I and therefore has been deleted from our listing. The twelve remaining supports include the last six supports listed above, the previously mentioned spring hanger (3-10 GB H 58) and the following supports identified in Items 1 through 4:

Item 1) 33-HB-F5A & 33 HB-S21 vn .u7xO 3 ,3u, y_,:

Item 2) 33-HB-S158 Item 3) 48-G5-S21

Mr. Boyce H. Grier, Director Page 5

• Item 4) 3-27HCR-S28A Should you have any questions or require additional information, please do not hesitate to contact us.

Very tru ours, n/

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cc: United States Nuclear Regulatory Commission Office of Inspection and Enforcement Division of Reactor Operations Inspection Washington, DC 20555 u '

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