ML20214K939
| ML20214K939 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 11/19/1986 |
| From: | Williams J TOLEDO EDISON CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| 1-665, CAL-R-III-85-13, IEIN-79-14, NUDOCS 8612020518 | |
| Download: ML20214K939 (7) | |
Text
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f TOLEDO EDISON JOE Docket No. 50-346
[4191249 2300 License No. NPF-3 lSl *dS 5' Serial No. 1-665 November 19, 1986 Mr. James G. Keppler Regional Administrator United States Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137
Dear Mr. Keppler:
This report summarizen Toledo Edison's effort regarding the NRC Confirmatory Action Letter CAL R III-85-13, dated October 17,1985 (Log No. 1-1258).
The pipe / pipe support inspection results, operability evaluations and corrective actions required to be completed prior to Restart, Phase I, are as follows:
As stated in CAL R III-85-13:
" Prior to Restart a.
Actions (1) Complete inspections /walkdowns utilizing Toledo Edison Company (TED) procedures on the piping system supports identified in Item b. and all other safety-related piping system supports inside Containment not listed in Table 1, and issue noncon-formance reports (NCRs) as appropriate.
(2) Resolve any resulting NCRs for those piping system supports listed in Table 1 including the completion of any necessary corrective actions to achieve piping system operability based on FSAR commitments /IE Bulletin 79-14 interim allowable stresses.
(3) Screen any resulting NCRs for safety-related piping system supports inside containment not listed in Table 1 and resolve those NCRs that are determined to be significant relative to system operability.
(4) Complete and close engineering evaluations for all open Facility Change Requests (FCRs) that relate to completed modifications which could impact piping system operability listed in hf Table 1.
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m'ma ' '&*'A 300 MADISON AVENUE TOLEDO, OH!O 43652 THE TOLEDO LOISON rnMPANY 8612O20518 861119 NOV 2 51986 PDR ADOCK 05000346 ca PDR
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Dock $t;No. 50- 346 ficense No.'NPF Serial No. 1-665~
- November 19,'1986 Page 2'
- (5) From the results obtained from actions delineated in Items a.(2) and a.(3), provide a basis for not performing inspections /-
walkdowns and resolution of resulting NCRs for all safety-related piping system supports not listed in Table 1."
Responses to CAL R III-85-13 r2(1)
Toledo Edison has completed the inspection of all piping system supports identified in Table 1 and all other safety-related piping system supports inside containment not. listed in Table 1.
Nonconformance Reports (NCR) have been issued for those' pipe
' supports as appropriate. The total scope of this effort has
-involved the inspection of 921 pipe' supports for Item b. and the inspectionfof 1444: pipe supports not in Table 1 but inside
' containment. These inspections resulted in 858 NCRs and ap-proximately 1291 NCRs, respectively. The majority of these NCRs documented minor deviations from the as-designed condition for the supports e.g.,-loose lock nuts, small dimensional discrep-ancies, staked threads, minor weld size deviations, missing washers, etc.
Supports with such minor deviations were evaluated.
and determined to be within the design allowable stresses listed in the USAR for Davis-Besse and acceptable for use as-is.
a.(2)
Toledo Edison has resolved the 858 NCRs resulting from the inspection of piping supports identified in Table 1.
As a result of these NCR resolutions, 202 NCRs required'the implemen-tation of field work. The physical work required as a. result of the 202 NCRs has been completed. Based on this, the corrective actions taken have restored the affected piping systems to their required FSAR condition.
For nonconformances significant enough to potentially affect the operabil-ity of an individual hanger, a review of the applicable Analysis Model for system operability in the as-found condition was performed. Of the 858 NCRs (63 Analysis Models) which were dispositioned, a review of the following Analysis Models for system operability was necessary:
SYSTEM ANALYSIS MODEL NO.
Low Pressure Injection 18B, 18D, 80A, T-010A Containment Spray 22F Containment Sump 32E (To ECCS)
High Pressure Injection 56D, 56F, T-009B Hydrogen Dilution 119L LPI/ Core Flood T-008 Pressurizer Relief (PORV)
TR-5639-2 1
s T
- Dohket No. 50-346 Cicense No.'NPF-3
' Serial No.=1-665 November 19,:1986 Page:3 The'above listed Analysis Models were used to calculate system stresses and displacements in order to determine system operability-based on the
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-as-found system conditions. The evaluations indicate:
1.
.Results of calculations using Analysis Models 18B, 18D, 80A, 32E, 56D, 56F, T-009B, 119L and T-008.were within FSAR' requirements.
12.:
Results of calculations using Analysis Models T-010A and 22F
. exceeded FSAR requirements but were within the interim etress levels utilized for IE Bulletin 79-14 evaluations. At no time was.the use of Code Case N-411 required to establish the opera-bility of these systems.
3.
Results of ' calculations using Analysis Model TR-5639-2 (the Pressurizer Pressure Operated Relief Valve (PORV)) would have exceeded IE Bulletin 79-14 interim allowable stress levels if left in the' previous configuration. This configuration involved a loop seal filled with condensate upstream of the PORV held at temperature by external heat tracing. However, during the current outage a drain line upstream of the PORV was installed.
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The heat tracing for the loop seal was'also removed. The drain
'line will keep the piping upstream of the PORV free of accumu-lated water (loop seal). Thus, the potential loadings due to water slug acceleration in the PORV discharge line is eliminated.
Currently, the governing operating mode for this system is a 2450 poig, 400*F subcooled water discharge'(Pressurizer becomes solid during transient). This case has been evaluated by Teledyne Engineering Services (TES).- During a recent NRC inspection at TES, it was found that some modeling discrepancies existed in this analysis, causing the computer model to deviate from the as-built condition. Bechtel Power Corp., Gaithersburg, MD, has performed an independent evaluation of the TES analysis, correcting the modeling and dimensional deviations in the process, and concluded that these differences had a minimal effect on the TES results.
In addition, the Bechtel reanalysis indicated two supports which were not adequately designed for the expected loadings. These supports were modified to ensure their adequacy under. design loadings.
This system is currently evaluated for the bounding operating mode of operation and will be in a condition that meets the FSAR requirements upon plant Restart.
It should be noted that the previous configuration (with loop seal) was a unique configura-tion and therefore similar conditions which could potentially affect system operability do not exist in'other systems.
m
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Docket Ns. 50-346 ticense No.-NPF -
cSerial'No. 1-665 November 19,'1986
.Page 4 It was found that approximately 15 supports were mislocated between one foot to several feet from their design locations.:
tMch of these supports was evaluated either by analysis model modification or by other evaluation techniques _to confirm system operability and acceptable stress levels in piping and supports.
a.(3)
Toledo Edison has-reviewed and resolved operability concerns for NCRs and Potential Condition Adverse to Quality;(PCAQ) Reports
- for safety-related piping system supports inside containment not listed in Table 1.in accordance with Toledo Edison procedure NEP-060, Processing NCRs, SDRs and SDDRs, and NEP-063, Process-ing PCAQ Reports.
a.(4)
Toledo Edison has completed reviews of open FCRs for nodifica-tions related to piping and supports that could impact safety-related piping system operability for those systems listed in Table 1.
The engineering reviews of these open FCRs indicate that they do not impact the ability of the piping / pipe supports
.to meet the FSAR allowable stress requirements.
a.(5)
Based upon the results obtained from the actions performed under Items a.(2) and a.(3), it is Toledo Edison's position that inspections and resolution for NCRs and PCAQs'outside of the Table 1 systems can be completed after plant Restart because:
1.
The majority of discrepancies that have been identified have been determined to be minor in nature. These include such items as loose lock nuts.. small dimensional discrep-ancies, staked threads, minor weld size deviations, missing washers, etc.
Similar deficiencies were' evaluated for systems listed in Table 1 and found in most cases not to affect support functions but.were reworked to meet the original design.
2.
Those deficiencies for systems in Table 1 which were not of a minor nature such as baseplate gaps, loose anchor bolts, or loose components were evaluated either on their own merit or incorporated into a system operability evaluation.
When a support was evaluated on its own merit it was required to be able to withstand, at a minimum, the origi-nel design load.. If the support could not pass this test, it was assumed to be nonfunctional'in the system operabil-ity evaluation. Although certain deficiencies were fairly significant relative to support operability, the results of the system operability evaluations (susmarized in Section
.a.(2)) indicateLthat, other than the Pressurizer Relief System, the deficiencies did not cause system inoperability.
3.
Although the Pressurizer Relief System stresses created during the June 9, 1985 activation of the system were outside the IE Bulletin 79-14 interim allowable Ifmits,
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Docket Ns. 50-346 License No. NPF-3 Serial No.1-665 November 19, 1986 Page 5 system operability evaluation for Item a.(2) and the examinations performed on the system piping indicate that the stresses created did not cause the system to be seriously degraded or plant safety to be significantly compromised. Modifications to the Pressurizer Relief System to eliminate the PORV loop seal and strengthen certain hanger designs performed during the current outage have removed concerns about future overstressing of this system.
4.
The NCRs generated in systems other than those in Table 1 are similar to the NCRs which have been resolved for the systems in Table 1.
It is therefore expected that future NCR resolutions will be similar to those issued for sup-ports which have already been evaluated and that system operability evaluations, which remain to be performed, will indicate similar acceptable results as those operability evaluations already performed.
The NCRs or PCAQs generated as a result of required inspections for piping systems not listed in Table 1 and outside of the containment have been and will continue to be reviewed in accordance with NEP-060 and NEP-063. Those items determined to be significant relative to system operability will be resolved within the time limits identified in NEP-060 and NEP-063. Toledo Edison is approximately 80% complete for these remaining support inspections.
Deficiencies documented under inspection plans IP-M-001 and IP-M-002 for systems not listed in Table 1 and outside of containment will be rasolved and corrected prior to the end of the next refueling outage as required by RIII CAL 85-13. Item 3.
Upon completion of these remaining inspections and NCR/PCAQ resolutions, Toledo Edison will provide a final summary report of the program results.
Conclusions Reached The piping support inspection and verification program conducted under Toledo Edison Inspection Plan IP-M-001 indicated that numerous nonconforming conditions were either not identified, incorrectly identified, or incompletely identified in the post construction quality control inspections and the IE Bulletin 79-14 Program. Also, incorrect or incomplete transfer of information within the scope of the IE Bulletin 79-14 Program had taken place and, therefore, some as-built conditions which were identified during the program were not reflected in as-built drawings or considered in engineering evalua-tions.
Dockht N:. 50-346 License No. NPF-3
~*
Serial No. 1-665
. November 19, 1986
.Page 6 Evaluation of these discrepancies indicates that for the as-built system configuration, the stresses posed no system operability concerns, with the exception of the unique problems of the PORV discharge line as discussed in a.(2).
System operability reviews have conclusively shown that the collective effects of these individual deficiencies have not caused concerns regarding safe operation of these piping systems under the applicable design conditions.
Very truly yours, yh u,.oI
/
- J S:PHS:p f cc:
DB-1 NRC Resident Inspection NRC Region III Incident Response Center
y TABLE 1 (Item b. from CAL R III-85-13)
Systems
"(1)- Outside Containment:
High Pressure Injection Low Pressure Injection / Decay Heat Removal Auxiliary Feedwater*
Auxiliary Feedwater Turbine Steam Supply *
(2) Inside Containment:
_High Pressure Injection Low Pressure Injection / Decay Heat Removal Auxiliary Feedwater*
Containment Spray (accessible portion)
Core Flood Hydrogen Dilution Pressurizer Relief The results of reviews and engineering evaluations for these systems do not have to be considered when determining the operability basis (see Item a.(5)) of safety-related piping systems not listed in b.(1) and b.(2) above."