ML13316B198
| ML13316B198 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 11/28/1988 |
| From: | Knighton G Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML13316B196 | List: |
| References | |
| DPR-13-A-115 NUDOCS 8812060091 | |
| Download: ML13316B198 (10) | |
Text
p8 REGoj E
0 UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 SOUTHERN CALIFORNIA EDISON COMPANY SAN DIEGO GAS AND ELECTRIC COMPANY DOCKET NO. 50-206 SAN ONOFRE NUCLEAR GENERATING STATION, UNIT NO. 1 AMENDMENT TO PROVISIONAL OPERATING LICENSE Amendment No. 115 License No. DPR-13
- 1. The Nuclear Regulatory Commission (the Commission) has found that:
A. The application for amendment by Southern California Edison Company and San Diego Gas and Electric Company (the licensee) dated March 10, 1988 as supplemented March 22 and 29, 1988 complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application,.
the provisions of the Act, and the regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.
812060091 D 1128 PDR ADOCK::
05000206.
P PDICI
-2
- 2. Accordingly, the license is amended by changes to the Technical Speci fications as indicated in the attachment to this license amendment, and paragraph 3.B. of Provisional Operating License No. DPR-13 is hereby amended to read as follows:
B. Technical Specifications The Technical Specifications contained in Appendix A, as revised through Amendment No. 115, are hereby incorporated in the license. Southern California Edison Company shall operate the facility in accordance with the Technical Specifications, except where otherwise stated in specific license conditions.
- 3. This license amendment is effective as of the date of its issuance and must be fully implemented no later than 30 days from the date of issuance.
FOR THE NUCLEAR REG LATORY COMMISSION George. Knighto, Director Project Directorate V Division of Reactor Projects -
- III, IV, V and Special Projects
Attachment:
Changes to the Technical Specifications Date of Issuance: November 28, 1988
ATTACHMENT TO LICENSE AMENDMENT NO.115 PROVISIONAL OPERATING LICENSE NO. DPR-13 DOCKET NO. 50-206 Revise Appendix A Technical Specifications by removing the pages identified below and inserting the enclosed pages. The revised pages are identified by the captioned amendment number and contain marginal lines indicating the area of change.
REMOVE INSERT 60-0 60-0 through through 60-U 60-U
60-0 4.16 INSERVICE INSPECTION OF STEAM GENERATOR TUBING APPLICABILITY:
Applies to the inservice inspection and sampling selection for steam generator tubing.
OBJECTIVE:
To monitor the integrity of the steam generator tube primary boundary and provide guidance for corrective action when imperfections are observed.
SPECIFICATION:
A. GENERAL STEAM GENERATOR TUBE SELECTION The steam generators shall be inspected when shutdown by selecting steam generator tubes on the following basis:
- 1. Tubes for the inspection shall be selected on a random basis except where experience at San Onofre Unit 1 or experience in similar plants indicates critical areas to be inspected.
- 2. Each inspection shall include at least 3% of the total number of tubes in each steam generator to be inspected.
- 3. Inservice inspections may be limited to one steam generator on a rotating schedule encompassing 3% of the total tubes of steam generators in the plant if the results of previous inspections indicate that all steam generators are performing in a like manner.
- 4. Every inspection shall include all non-plugged tubes, id the steam generator(s) to be inspected, that previously had been classified as degraded tubes, except as specified in Specification C.1.
B. SUPPLEMENTARY INSPECTIONS If the inspections in Specification A indicate imperfections, additional inspections shall be required as follows:
- 1. If any of the tubes inspected pursuant to Specification A.3 are degraded tubes that were not classified as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration since their last inspection, inspect 3%
of the tubes in one of the uninspected steam generators.
Amendment No.
17,101, 115
60-P
- 2. If more than 10% of the tubes inspected in a steam generator are degraded tubes that were not classified as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration since their last inspection, or one or more of the tubes inspected have an imperfection in excess of the plugging limit, inspect an additional 3% of the tubes in that steam generator, concentrating on tubes in those areas of the tube sheet array where tubes with imperfections were found and on that length of tube where the imperfections were found. In addition, the rest of the steam generators shall be inspected in accordance with Specification A.2.
- 3. If the additional inspection in Specification B.2 indicates that more than 10% of the additionally inspected tubes are degraded tubes that were not classified as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration since their last inspection, or one or more of the additionally inspected tubes have an imperfection in excess of the plugging limit, inspect an additional 6% of the tubes in that steam generator in the area of the tubesheet array where tubes with imperfections were found and through that length of tube where the imperfections were found.
C. SPECIAL STEAM GENERATOR TUBE INSPECTIONS In addition to the general steam generator tube inspections performed in Specifications A and B, every inspection shall include the following special inspections:
- 1. Every inspection shall include all nonplugged tubes in one of the steam generators that previously had been noted as having discretely quantifiable imperfections greater than 30% at antivibration bar (AVB) intersections, and all non-plugged tubes in that steam generator that previously had been noted as having imperfections at AVB intersections which were not discretely quantifiable but which were identified during previous inspections as being in the 30 to 50% range.
- 2. At each steam generator inspection, all previously identified restricted tubes in either steam generator A or C shall be gauged by using eddy current probes to determine restriction sizes.
Amendment No. 11,77,115
60-Q D.
INSPECTION FREQUENCY The inspections in Specifications A and B above shall be performed at the following frequencies:
- 1. Inservice inspections shall be not less than 10 nor more than 24 calendar months after the previous inspection.
- 2. If two consecutive inspections indicate that less than 10% of the total tubes inspected are degraded tubes that were not classified as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration, the inspections shall be not less than 10 nor more than 40 calendar months after the previous inspection.
- 3. Unscheduled inspections shall be conducted in accordance with Specification A in the event of primary-to-secondary leaks exceeding Specification 3.1.4.C. a seismic occurrence greater than an operating basis earthquake, a loss-of-coolant accident requiring actuation of engineered safeguards, or a major steam line or feedwater line break.
E. ACCEPTANCE CRITERIA
- 1. As used in this specification:
- a. Imperfection means an exception to the dimensions, finish, or contour required by drawing or specification. Detectable eddy current testing indications below 20% of the nominal tube wall thickness, may be considered as imperfections.
- b. Degradation means a service-induced cracking, wastage, pitting, wear or general corrosion occurring on either inside or outside of a tube.
- c. DearaidedTube means a tube containing imperfections greater than or equal to 20% of the nominal wall thickness caused by degradation above the tube roll expansion. Also. a tube with an imperfection in the region one-half inch below the uppermost one inch of sound roll, is considered a degraded tube.
- d. Defec means an imperfection of such severity that it exceeds the plugging limit or an imperfection located in the uppermost one inch of the tube roll expansion. A tube or sleeve containing a defect is defective.
Amendment No. 37,X9X,115
60-R
- e. Plugging Limit means the imperfection depth at or beyond which plugging of the tube must be performed. The plugging limit is equal to or greater than 50% of.the nominal tube wall thickness, except where sleeves are installed, in which case the plugging limit is equal to or greater than 40% of the nominal sleeve wall thickness.
For the tube roll expansion region, the following criteria apply:
(M) Any tube containing an imperfection within the uppermost one inch of sound roll shall be considered defective.
(1i)
Any imperfection is acceptable below the uppermost one inch of sound roll.
- f. Tube Roll Expansion means that portion of the tube which has been increased in diameter by a rolling process.
- g. Sound Roll means a tube roll expansion which is fully expanded such that no crevice exists between the outside diameter of the tube and the tubesheet.
- 2. If, in the inspections performed under Specification A,
- a. Less than 10% of the total tubes inspected are degraded tubes that were not classified-as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration, and
- b. No tube inspected exceeds the plugging limit, plant operation may resume.
- 3. If, in the inspections performed under Specification B,
- a. Less than 10% of the total tubes inspected are degraded tubes that were not classified as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration, and Amendment No. 3 115
60-S
- b. No more than 3 of the tubes inspected exceed the plugging limit, plant operation may resume after performance of the corrective action in Specification F.
- 4. If, in the inspections performed under Specification 8,
- a. More than 10% of the total tubes inspected are degraded tubes that were not classifted as degraded tubes during the previous inspections or have previously detected imperfections that have increased more than 10% wall penetration, or
- b. More than 3 of the tubes inspected exceed the plugging limit, prior to resumption of plant operation the situation shall be reported in a Special Report to the Commission in accordance with Technical Specification 6.9.2 for approval of the proposed remedial action.
- 5. The results of inspections performed under specifications A or 8 for all tubes in service which have defects below the uppermost one inch of tube roll expansion shall be reported to the Commission in a Special Report pursuant to Technical Specification 6.9.2 at least seven days prior to the resumption of plant operation. The report shall include:
- a. Identification of applicable tubes, and
- b. Location and size of the degradation.
- 6. If in the inspections performed under Specification C.1, wear rates are observed at AVB intersections which are inconsistent with the 50% plugging criterion, prior to resumption of plant operation the situation shall be reported in a Special Report to the Commission in accordance with Technical Specification 6.9.2 for approval of the proposed remedial action.
- 7. If in the inspections performed under Specification C.2 progression of the denting process is observed to be recurring, prior to resumption of plant operation the situation shall be reported in a Special Report to the Commission in accordance with Technical Specification 6.9.2 for approval of the proposed remedial action.
Amendment No.
37,91,L0ZX05,115
60-T F. CORRECTIVE ACTION All leaking tubes,-defective tubes, and tubes with imperfections exceeding the plugging limit shall be repaired or plugged.
The Surveillance Requirements for inspection of the steam generator tubes ensure that the structural integrity of this portion of the Reactor Coolant System will be maintained.
The program for inservice inspection of steam generator tubes is based on Regulatory Guide 1.83, Revision 1. Inservice inspection of steam generator tubing is essential in order to maintain surveillance of the conditions of the tubes in the event that there is evidence of degradation due to design, manufacturing errors, or inservice conditions that lead to corrosion. Inservice inspection of steam generator tubing also provides a means of characterizing the nature and cause of any tube degradation so that corrective measures can be taken.
The plant is expected to be operated in a manner such that the secondary coolant will be maintained within those chemistry limits found to result in negligible corrosion of the steam generator tubes. If the secondary coolant chemistry is not maintained within these limits, localized corrosion may likely result in stress corrosion cracking.
The extent of cracking during plant operation would be limited by the limitation of steam generator tube leakage between the primary coolant system and the secondary coolant system (primary-to-secondary leakage -.3 gallons per minute per steam generator). Cracks having a primary-to-secondary leakage less than this limit during operation will have an adequate margin of safety to withstand the loads imposed during normal operation and by postulated accidents.
Operating plants have demonstrated that primary-to-secondary leakage of.3 gpm per steam generator can readily be detected by radiation monitors of steam generator blowdown. Leakage in excess of this limit will require shutdown during which the leaking tubes will be located and plugged and additional inspections performed.
If a defect should develop in service, it will be found during scheduled inservice steam generator tube examinations. Plugging will be required for all tubes with imperfections exceeding the plugging limit of 50% of the tube nominal wall thickness, except where sleeves are installed,
- in which case the plugging limit is 40% of the nominal sleeve wall thickness. A plugging limit of 50% for tubes and 40%
for sleeves ensures that defects will not occur between inspection intervals. Tubes with defects below the uppermost one inch of a sound roll may remain in service, provided there are no imperfections in this portion of the tube. The distance of one inch includes a 0.25 inch eddy current measurement uncertainty.
Amendment No. ;7,1,Y0,115
60-U The results of tube ID gauging and dent detection conducted in San Onofre Unit 1 steam generators demonstrate that the denting process has been arrested. Continuing assurance of this condition can be provided by performing a program of limited tube ID gauging and dent detection in either steam generator A or C on a refueling outage frequency. Adequate surveillance of denting related tube restrictions can be maintained at refueling intervals by noting any new :
restrictions during the conduct of general surveillance and AVB inspections and by gauging tubes which have previously been noted as being restricted. Progression of denting can also be monitored in either steam generator A or C by evaluating third and fourth support plate denting data obtained from the general surveillance and AVB inspections as well as from the ID gauging program and comparing these results with those of previous inspections.
The results of AVB area inspections conducted in San Onofre Unit I steam generators demonstrate that AVB modifications installed during the Cycle VI refueling outage were successful in eliminating significant growth of tube wall penetration indications at AVB locations. Continuing assurance of this condition can be provided by performing U-bend inspections at refueling outage intervals of tubes having wall penetration indications in excess of 30% at AVB locations.
Amendment No. M,X,49,115