L-99-082, Dockets Licensee Plan for Bvps,Unit 1,safety-related Small Bore Piping Evaluation Project Discussed in NRC 990311 Public Meeting at BVPS
| ML20207A059 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 05/17/1999 |
| From: | Jain S DUQUESNE LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-91-18, L-99-082, L-99-82, NUDOCS 9905260122 | |
| Download: ML20207A059 (3) | |
Text
A s
Beaver Valley Power Station Shippingport, PA 15077 0004 i
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May 17, 1999 e
Nuclear Pcwet Division -
L-99-082 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001
Subject:
Beaver Valley Power Station, Unit No.1 i
Docket No. 50-334, License No. DPR-66 Safety Related Small Bore Piping Evaluation Project The purpose of this letter is to docket our plan for the Unit 1 Safety Related Small Bore Piping Evaluation Project (SBPEP) discussed in the NRC public meeting on March 11, j
' 1999, at the Beaver Valley Power Station (BVPS).
A.
Background and Current Operability i
An assessment of the BVPS Unit'l' safety-related small bore (s 2" diameter) piping design was performed in 1997 to evaluate the extent of condition for design code discrepancies identified through the BVPS Corrective Action Program. This assessment included a review of approximately 650 -isometric drawings, 2400 supports and i
. associated interfaces between the safety related and non-safety related piping. The j
assessment concluded that the small bore piping systems at BVPS Unit 1, although not in full compliance with the design code of record, are safe to operate in their current condition. Based on this assessment, a Generic Letter 91-18, Revision 1 operability evaluation (BCO #1-97-007) was developed and is currently in effect.
A project has been initiated to further evaluate the Unit I small bore piping to identify l
and resolve discrepancies from the design code of record, ANSI B31.1 1967-S71. This
' gi project is referred to as the Unit 1 Safety-Related Small Bore Piping Evaluation Project (SBPEP.)
j B.
Unit 1 Safety-Related Small Bore Piping Evaluation Project (SBPEP)
Engineering Standard ES-N-018, titled " Design Criteria Document for Evaluation of Small Bore Piping Systems" has been developed to provide details of the evaluation criteria to be used in the SBPEP. This standard defines the specific methodology that will be used to evaluate small bore safety related piping and pipe supports.
DELIVf RING 00ALliY 9905260122 990517 E.N f R S1 PDR ADOCK 05000334 p
P-I Beaver Valley Power Station, Unit No.1 Safety Related Small Bore Piping Evaluation Project Page 2,
- ES-N-018 allows for a graded approach in the analytical metl ods (simplified or detailed computer analysis) to be employed based upon the level of rigor necessary to evaluate design code compliance.
When employing conservative simplified methods (hand i
calculations or simplified computer analyses), verification of the as-installed configuration will not be performed. Verification of the as-installed configuration will be performed when utilizing detailed computer analyses performed in conjunction with
' the Engineering Standard. Both simplified and detailed analysis methods are consistent l
with those described in BVPS Updated Final Safety Analysis Report Appendix B and meet the intent of the 1967 ANSI B31.1 Code.
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The preferred resolution method for identified discrepancies will be to restore compliance with the original design code. However, alternative resolutions may be
- submitted to the NRC for review when appropriate, (e.g., for inaccessible or high l radiation locations).
Finally, as additional information is obtained, we will assess the impact on the existing operability evaluation. Although operability impacts are not anticipated, this assessment will provide added assurance that identified discrepancies do not change the basis for conclusions of the existing operability evaluation.
C.
' Schedule and Status Systems are being prioritized for review based on risk and design insights. Should modifications be determined to be appropriate, a planning window approach will be used to determine the implementation schedule.
Refueling outage related modifications identified at least 15 months in advauce will be incorporated into the next refueling outage.
Modifications may also be performed during non-outage periods and coordinated with the 12 week schedule.
Project work is in progress. Nuclear Engineering Department personnel performed selected small bore piping walkdowns in containment during the Spring 1999 Unit I surveillance outage. The purpose of these walkdowns was to obtain supplemental dimensional information pertaining to the piping supports for use in planned evaluations.
Completed actions include issuance of an approved project plan and the Engineering Standard. A project database defining piping and supports within the scope of this project has been developed. Additional support walkdowns have been defined. Design evaluations are in progress and are expected to be completed prior to the end of 2001.
j
. The SBPEP will be completed prior to the conclusion of IRIS (currently projected for March of 2003).
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m Beaver Vriley Power Station, Unit No.1 Safety Related Small Bore Piping Evaluation Project Page 3; As discussed in the NRC public meeting of May 11,1999, at Beaver Valley Power 1 Station, we believe that the above approach for implementing potential piping and pipe support modifications will provide for an orderly and safe resolution of the identified issues.
Sincerely,-
.b Sushil C. Jain
.Commitmelg The SBPEP will be completed prior to the conclusion of IRIS (currently projected for March of 2003).
c:. Mr. D. S. Collins, Project Manager Mr. D. M. Kern, Sr. Resident Inspector
- Mr. H. J. Miller, NRC Region I Administrator