ML20154F037
| ML20154F037 | |
| Person / Time | |
|---|---|
| Issue date: | 05/10/1988 |
| From: | Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | |
| Shared Package | |
| ML20153H026 | List: |
| References | |
| FOIA-88-318, TASK-PII, TASK-SE SECY-88-050A, SECY-88-50A, NUDOCS 8805230074 | |
| Download: ML20154F037 (4) | |
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POLICY ISSUE May 10, 1988 SECY-88-50A For:
The Comissioners From:
Victor Stello, Jr.
Exe:utive Director for Operations
Subject:
REP 0FT ON THE MEETING WITH NUMARC EPRI, AND INPO ON STATUS OF lhDUSTRY'S EROSION / CORROSION PROGRAM
Purpose:
To supplement SECY-88-50 with a surmary of the meeting with representatives of the Nuclear Management and Resource Council (NUMARC), ilectric Power Research Institute (EPRI),
anc Institute of Nuclear Power Operations (INFO) on the status of industry's erosion / corrosion program.
Backaround:
SECY-88-50 was issued to infom the Comission of the results of the staff's survey on pipe wall thinning in operating plants and the industry practice for monitoring erosion / corrosion.
The staff review indicated that the pipe-wall thinning problem is widespread for single-phase and two-phase high-energy carbon steel systems.
Monitoring programs exist for two-phase systems at virtually all plants.
However, the scope and extent of the progrars nry from plant to plant and failures continue te I
- occur, Industry guidance has been developed for single-phase piping, and the majority of plants are comitted to use the guidelines, althouch the industry had not acted to ensure imple-nentationatallpIants.
Discussion:
On March 17, 1968, representatives of NUMARC provided a briefing to the staff on recent industry efforts to implement a program N cddress erosion / corrosion.
In resperse to the Decerr.ber 1986 feedwater pipe rupture accidert at Surry, the NUMARC Working Group on Piping Erosion / Corrosion was forved to address the potential pipe-wall thinning problem CONTACT:
P. Wu, CEST/NRR Ext. 20026 x
05230074 080510
.I CF GECY 9
9-050A yy
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The Cemissioners in single-phase carbon steel piping systems. The working group developed guidance ?. hat defined an acceptable approach for moni-toring erosion /corrcsion in single-phase piping. These guidelines were found arceptabla by the staff and distributed to all U.S.
nuclear utilities in June 1987. On March 20, 1987, llM0 issued a significant operating event report (SOER) which recomended the establishment of a program to address this issue.
The NUMARC guidelines on erosion / corrosion in single-phase piping basically called for:
an analysis to be performed, using methodology developed by EpRI or an equivalent method, to assess the susceptibil-ity of the particular plant to single phase erosion / corrosion an inspection of piping components most susceptible tc erosion /cortosion ranked by the analysis method used ae evaluation to detennine if the plant specific acceptance criterie used for determining thother a corponent would potentially reach an unacceptable well thickness (i.e.,
hcve to be replaced) before the next scheduled cutage was at least as conservative as that specified in the guidelines an initial inspection, encompassing at least 15 locations, to be completed no later than October 1988.
In the meeting held on March 17, 1988, NUPARC representatives provided the staff with results of its survey conducud at the i
end of 19F7. The survey requested a sumary of erosion / corrosion program status from all NUMARC members. Specifically, the survey asked each U.S. nucleir utility whether thef *.ad adopted the NUPAR; guidlines anc the status of tie ind$ adual actions called for by the guidellr.es (i.e., analysis, initial inspection, and replacement of compocents).
4 Results of the NUMAkC survey indicate that 112 of 113 U.S. nuclear pwer plants have comitted to implement an erosion / corrosion The monitoring program for single-phase piping by(October 1988.EWP),wa reraining plant, a new boiling-water reactor to be exadned during the refueling cutage in the sprior of 1989.
Subsequent to the March 17, 1988, meetir<g, this BWR hac a main-tenance outage at which time it inspt ed single-phase piping.
Therefore, by s'teber 1988 (11 nuclear poter plantt will have completed an.ypection for erosion / corrosion in single-phase piping.
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The comrissioners As of early 1988, 55 plants have completed inspections.
Components were replaced in 19 of these plants because of sir.;1e-phase erosion / corrosion. Arnor.g the 19 plants replacing components, 10 replaced more tMii five components and 9 replaced fewer than 5 cceponents.
Only one BWR replaced components because of erosion / corrosion.
This demonstrated that the erosion / corrosion problem is more extensive for pressurized-water reactors (PWRs).
4 The staff is encouraged that industry has taken the initiative to address the single-phase erosion / corrosion issue by ensuring that initici inspections are conducted at all U.S. nuciear power plana However, to fully address all concerns with regard to this issue. assurances are needed that all plants have system-Finlly addressed the issue of two-phase erosion / corrosion and procedurally implemented long-term programs for single-phase and two-phase piping systems.
To accress there concerns NUMARC is sponsoring EPRI in the development of a computer-based program for two-rhasererosion/
corrosion. This program is similar to the single-phase program and is scheduled for completion by EPRI during the fall of 1988.
its issue regarding a long-term program has been addressed by INPO SOER-07-3, which recontends long-tem inspection programs for two-phase and single-phase piping.
The staff has developed a program to assess the effectiveness of ind.stry efforts by visitirig 10 plants by the end of FY 1983.
Specifically, the staff and its consultants will verify each liceesee's long term connitrent to NUMARC's guidelines for single-phase piping and the implementation of monitoring programs
'~ erosion / corrosion in single-phase and two-phase lines, ecults of these site visits will be factured into the basis for staff actions to close out this issue. If industry actions are cetermined to be acceptable, no further regulatory action would be teken.
If industry actions are determined to be inadequate, a staff position will be prepared te equire implementation of a program for erosion / corrosion.
3rre y:
?:U9D.0 representatives indiceted that all nuclear power plants will heve completed inspections for single-phase erosion /corrosun by October 1988.
The technical content of the programs at all utilities reets the intent of the NUMARC guidelines. The problem is core extensive for PWP.s than BWRs. Staff plant inspections 1
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The Comissioners '
will be corrpleted by October 1988 and additional regulatory i
requirements prepared by December 1988, if necestery.
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Victor Stello, Jr.p l
.l Executive Director for Operations
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