ML13333B718
| ML13333B718 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/04/1982 |
| From: | Paulson W Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TASK-03-06, TASK-3-6, TASK-RR NUDOCS 8206170210 | |
| Download: ML13333B718 (7) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 June 4, 1982 Docket No. 50-206 LICENSEE: SOUTHERN CALIFORNIA EDISON COMPANY FACILITY: SAN ONOFRE NUCLEAR GENERATING STATION, UNIT NO. 1
SUBJECT:
SUMMARY
OF MAY 3, 1982 MEETING On May 3, 1982, members of the NRC staff met with representatives of Southern California Edison Company (SCE) to discuss topics related to the seismic reanalysis of San Onofre Nuclear Generating Station, Unit No. 1 (SONGS 1).
The topics to be discussed were the licensee's (1) seismic reanalysis of the turbine building and the fuel storage building, (2) response to our February 17, 1982 request for additional information regarding masonry walls, (3) response to our letter dated April 2, 1982 regarding system response and structural concerns, and (4) seismic reanalysis of balance of plant mechanical equipment and piping (BOPMEP). The reanalyses were conducted as part of the Systematic Evaluation Program. A list of attendees is enclosed.
During the meeting, the licensee provided four submittals dated April 30, 1982 for NRC review that addressed the above cited topics. The licensee summarized these documents. The highlights are as follows:
Response to NRC April 2 letter (50.54f)
- 1. Results of analyses to support revised emergency operating procedures in the event of a steam line break will be dis cussed at the meeting with the staff scheduled for May 14, 1982. Target for completion of the revised procedures is May 21, 1982.
- 2. With regard to masonry walls, the licensee concluded that gross failure of the walls won't occur. The licensee also concluded that based on analyses, the stress levels in the face of the masonry block is such that the walls won't spall and therefore they did not look at the effect of spalling on equipment. An inspection of grouting and rebar in sections of masonry walls that were removed for.modifications showed that the construction and placement of rebar was as shown on the drawings. Details of a limited test program to verify the licensee's methodology will be discussed during a meeting scheduled for May 11-13, 1982.
DESIGNATED ORIGINIAL 8206170210 820604 PDR ADOCK 05000206 P
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June 4, 1982
- 3. There are two reports outstanding with regard to the seismic reevaluation of SONGS 1. The report on cable trays and conduit was scheduled for submittal on May 15, 1982 (subsequently delayed per licensee's letter of May 14, 1982) and the results of the analyses of accident mitigating systems will be submitted by November 1, 1982. Supplementary information supporting the reevaluation spectra will be provided in the middle of May. The effect of the exceedances (up to 10%) of the Housner spectra anchored at 0.67g discussed in the NRC staff's letter of April 5, 1982 will be addressed by the end of August 1982. The licensee also stated that the floor spectra will be provided.
- 4. The licensee indicated that the south turbine building extension and the east feedwater heater platform will be impacted by other SEP topics. SCE wants to consider seismic related modifications to these structures during the SEP Integrated Assessment. No safety basis was provided for deferring the modifications to these structures beyond January 1, 1983. The licensee plans to provide additional justification prior to startup. Modifications to the fuel building are underway and will continue after startup.
At the request of the.NRC staff the licensee presented a brief overview of soil compaction characteristics encountered during excavation associated with modifications of the San Onofre Unit 1 turbine building north and west extensions. They informed the NRC staff of an ongoing investigative effort undertaken to assess the impact of areas of low soil compaction (80-85% modified Proctor) on the stability of safety related structures, piping and related facilities. Because the investigative effort was still in its formative state and substantive details were not as yet available, the licensee stated that results would be provided at a later date prior to startup presently scheduled for June 4, 1982.
The staff requested that the licensee presents the results of the on-going investigative efforts as soon as possible addressing the details of all office, field and laboratory investigation, exploration, and testing efforts performed to evaluate the inplace engineering properties of subsurface materials beneath and adjacent to safety related structures with special emphasis placed.on delineating the area, extent and depth of low soil compaction zones. The staff also requested that the licensee present details of any effort taken to enhance the engineering properties of the soils encountered and to provide test results and evaluations demonstrating the results of such efforts. The staff informed the licensee that NRC review and analysis of the engineering properties and stability of the inplace soils would be conducted essentially in accordance with Section 2.5.4 of the current NUREG-0800.
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June 4, 1982 SCE discussed the results of the reanalyses of the balance of plant mechanical equipment and piping. The reanalysis was conducted for a 0.67g Housner SSE (SONGS 1 was licensed based on a design 0.25g Housner spectra and operability at 0.5g Housner). For the 0.67g Housner SSE, lines and items of equipment would need.additional support to meet structural reanalysis criteria; however, most of these meet the licensee's criteria.for operability. These criteria are specified in Table 3-6 of the April 30, 1982 submittal. and are shown in enclosure 2. One issue raised by the staff pertained to the interface between the analysis of the main loop of primary coolant pressure boundary and the analysis of the branch piping. The licensee stated that the two sets of calculations were not reviewed to deter mine that the results at the boundaries were compatible..
The licensee stated that an additional analysis of the reactor coolant loop by Westinghouse, using an additional time history as requested by the-NRC staff, would not be performed. SCE could not answer why the results of the BOPMEP (high stresses) were different from those expected as indicated in-their April 28, 1980 letter. The licensee indicated that they did not have adequate time to prepare a proposal for those items that exceeded their operability criteria (enclosure 2).
SCE stated that they would get back to us in this regard prior to startup.
Walter A. Paulson, Project Manager Operating Reactors Branch #5 Division of Licensing
Enclosures:
As stated cc w/enclosures:
See next page
Mr. R. Dietch 4 -
June 4, 1982 cc Charles R. Kocher, Assistant General Counsel James Beoletto, Esquire Southern California Edison Company Post Office Box 800 Rosemead, California 91770 David R. Pigott Orrick, Herrington & Sutcliffe 600 Montgomery Street San Francisco, California 94111 Harry B. Stoehr San Diego Gas & Electric Company P. 0. Box 1831 San Diego, California 92112 Resident Inspector/San Onofre NPS c/o U. S. NRC P. 0. Box 4329 San Clemente, California 92672 Mayor City of San Clemente San Clemente, California 92672 Chairman Board of Supervisors County of San Diego San Diego, California 92101 California Department of Health ATTN:
Chief, Environmental Radiation Control Unit Radiological Health Section 714 P Street, Room 498 Sacramento, California 95814 U. S. Environmental Protection Agency Region IX Office ATTN:
Regional Radiation Representative 215 Freemont Street San Francisco, California 94111 Robert H. Engelken, Regional Administrator Nuclear Regulatory Commission, Region V 1450 Maria Lane Walnut Creek, California 94596 ATTENDANCE LIST NAME AFFILIATION W. Paulson NRC J. Rainsberry SCE R. Krieger SCE R. Day Bechtel P. Eich Bechtel C. Myer Bechtel.
T. Bridges EG&G Idaho E. McKenna NRC D. Morton EG&G Idaho D. Crutchfield NRC W. Hall NRC T. Tsai NCT Engineering P. Y. Chen NRC R. Hermann NRC T. Cheng NRC T. Nelson LLNL N. Chokshi NRC K. Leu NRC D. Jeng NRC W. Russell NRC E. Marinos NRC
TABLE 3-6 INTEGRITY CRITERIA ALLOWABLES Components Stress Criteria Large (>2")
5.2 x Code Allowable(1)
Piping Small (<2")
Not Applicable Component Standard 5.2 x Component Design Support Load Rating Pipe Supports Structural Steel 3 x S (2)
Support Concrete Fasteners 3 x Ultimate Pullout All components except 2.36 x Code Allowable~l)
Mechanical Equipment concrete fasteners Concrete fasteners 3 x Design Load Rating Field Erected Tank S
u
)From Tables 3-1, 3-2 and 3-3 (2)Ultimate Strength 22
MEETING
SUMMARY
DISTRIBUTION Docket NRC.PDR Local PDR ORB Reading NSIC DCrutchfield HSmith WPaulson OELD OI&E ACRS (10)
SEPB EMcKenna WHall PYChen RHermann TCheng NChokshi KLeu Deng WRussell EMarinos