ML20153B213
| ML20153B213 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 03/11/1988 |
| From: | NRC OFFICE OF SPECIAL PROJECTS |
| To: | |
| Shared Package | |
| ML20127A683 | List:
|
| References | |
| NUDOCS 8803210482 | |
| Download: ML20153B213 (2) | |
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NUCLEAR REGULATORY COMMISSION 3. i
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SECUOYAH NUCLEAR POWER PLANT UNITS 1 & 2 SAFETY EVALVAT'ON REPORT FOR EMPLOYEE CONCERNS ELEMENT REPORT 220.3(B), REVISION 2 "SUPPORT DESIGN GENERAL DESIGN OF SUPPORTS" I.
Subject Category:
Engineering (20000)
Subcategory:
Support Design General (22000)
Element:
Acceptance Criteria for Overlap Areas uf Calculations (22003)
Concerns:
00-P.5-005-008. IN-85-886-001 The basis for Elemen; Report 220.3(B), Revision 2 are Employes Concerns 00-85-005-008 and IN-85-886-001 which question TVA's design and construction of supports.
II.
Summary of Issues The Employee Concerns Task Graap (ECTG) report identified the following four issues from the employee concerns:
1.
Seismic supports are designed inadequately.
2.
They are too rigid and will break loose during a seismic event and will fall on other equipment and damage it.
3.
Pipe support designs are not constructible.
4 Seismic support design criteria are non existent.
In addition to these four issues, the ECTG report identified two additional issues which were addressed in Element Feports 204.4 and 201.3.
III. Evaluation A technical review of Employee Concerns Element Report 220.3(B), Revision 2 was performed by NCT Engineering, Inc. under NRC Contract No. 05-86-156.
The c3 Jg results cf this review are surrarized in the attached NCT technical evaluatico gga.
report dated December 6, 1987 on Employee Concerns Elerent Report 220.3(B),
.go Revision 2.
c)o Element Report 220.3(B), Revision 2 found that the employees concerns were u
only valid for the issue of implementation of design criteria at Seouoyah.
eu 88 This finding was based on the review of a sample of pipe support calculations g<
at Sequoyah. TVA's proposed corrective action to the ECTG report finding was to perform calculations for the cbservations noted in the ECTG report for nine n
88 pipe supports. This correctiv'e action was determined to be a non restart item m a.a-by TVA ano, therefore, final verification of TVA's corrective action by ECTG had not been performed.
Thc ECTG report also stated that issue 3 constructibility of pipe suoports, had been addressed in F.lement Report 222.3.
Element Report 222.3 is the subject of a separate NRC safety evaluation, gQ
2-The issue of pipe support design criteria has been addressed by the PRC staff as part of the staff's review of TVA's Sequoyah Nuclear Performance Plan. As a result of the staff's review, TVA is currently evaluating ell rigorously analyzed pipe supports to a single design critaria document.
Based on the previous review of the pipe support calculations, the staff considers part of the employee concern with TVA's design criteria for pipe supports to be valid. The staff's evaluation of the current TVA pipe support calculation effort will be addressed in a separate evaluation of TVA's calculation program.
The NCT technical evaluation report addresses the remaining issues in Element Report 220.3(B), Revision 2 including TVA's corrective action on the support deficiencies identified in the element report. The NCT review of Element Report 220.3(B), Revision 2 and TVA's recently generated calculations concludes that ECTG's review of those issues and TVA's corrective actions are adequate. The staff concurs with the conclusions presented in the NCT technical evaluation report.
IV. Conclusions Based on the review of Employee Concerns Element Report 220.3(B), Revision 2 and TVA's current program to evaluate piping supports at Seouoyah, the staff concludes that Employee Concerns 00-85-005-008 and IN-85-886-001 have been adecuately addressed. The issue of pipe support constructibility is the subject of a separate staff evaluatipn on Element Report 222.3.
TVA's current program to evaluate piping supports will be the subject of a separate NRC evaluation on the Sequoyah Nuclear Performance Plan.
V.
Addendum The safety evaluation for this element report specified the completion of the NRC's review of the piping support evaluation as an open restart issue.
The review of regenerated pipe support calculations was ccmpleted during an inspec-tion during the week of February 15, IN 8.
This review did not identify any open restart issues on pipe supports.
Therefore, the staff has corpleted its restart evaluation of the regenerated pipe support calculations.
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