ML20093M794
| ML20093M794 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 07/31/1983 |
| From: | Nagata P EG&G, INC. |
| To: | Koo W Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20093M766 | List: |
| References | |
| CON-FIN-A-6429, RTR-NUREG-0313, RTR-NUREG-313 EGG-FM-6251, EGG-FM-6521, TAC-46657, NUDOCS 8408010027 | |
| Download: ML20093M794 (40) | |
Text
{{#Wiki_filter:. EGG-FM-6251 > July 1983 l TECHNICAL EVALUATION OF INTEGRITY l OF THE COOPER NUCLEAR STATION REACTOR COOLANT BOUNDARY PIPING SYSTEM Peter K. Nagata ' s Idaho National Engineering; Laboratory , Operated by the U.S. Department of Enwgy". 2-m_
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EGG-FM-6251 i l l TECHNICAL EVALUATION OF INTEGRITY OF THE COOPER NUCLEAR STATION REACTOR COOLANT BOUNDARY PIPING SYSTEM
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Published July 1983 Peter K. Nagata Materials Engineering Branch Materials Sciences Division EG&G Idaho, Inc. . Idaho Falls, Idaho 83415 - 4 Responsible NRC Individual and Division: W. H. Koo/ Division of Engineering Docket No.: 50-298 TAC No.: 46657 Prepared for the U.S. Nuclear Regulatory Commission Under DOE Contract No. DE-AC07-76ID01570 FIN No. A6429 i
ABSTRACT NUREG-0313, Rev. 1, Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping, is the NRC staff's revised acceptable methods to reduca intergranular stress corrosion cracking in boiling water reactors. The responses to NRC Generic Letter 81-04 of Nebraska Public Power District concerning whether its Cooper Nuclear Station meets NUREG-0313, Rev. I are evaluated by EG&G Idaho, Inc. in this report. Particular attention was given the leak detection systems described in Regulatory Guide 1.45, Reactor Coolant Pressure Boundary Leak Detection Systems, referenced by Parts IV.B.I.a.(l) and (2) found on pages 7 and 8 of NUREG-0313, Rev. 1. . FOREWORD This report is supplied as part of the Selected Operating Reactor Issues Program being conducted for the U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor Regulation, Division of Licensing, by EG&G Idaho, Inc., Materials Engineering Branch. The U.S. Nuclear Regulatory Commission funded the work under the authorization, B&R 20 19 10 11. I l i l l l e ii
SUfEARY NUREG-0313, Rev. 1, Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping, is the NRC I staff's revised acceptable methods to reduce intergranular stress corrosion l cracking in boiling water reactors. The responses to NRC Generic Letter 81-04 of Nebraska Public Power District concerning whether its Cooper Nuclear Station meets NUREG-0313, Rev. I are evaluated by EG&G Idaho, Inc. in this report. Particular attention was given the leak detection systems described in Regulatory Guide 1.45, Reactor Coolant Pressure Boundary Leak Detection Systems, referenced by Parts IV.B.1.a.(1) and (2) found on pages 7 and 8 of NUREG-0313, Rev.1. As may be observed in the following table, Cooper Nuclear Station does
. not meet any of the parts of NUREG-0313, Rev. I evaluated in this document.
The following table is a synopsis of the EG&G Idaho, Inc. evaluation of Nebraska Public Power District's response to NRC Generic Letter 81-04. Additional Part of NUREG-0313, Data i Rev. 1 Evaluated Evaluation # Required Discrepancy Section II. II.C. Provides alternative to Yes Minor NUREG-0313, Rev. 1 Section III. ' Section IV. IV.B.I.3.(1). Providas alternative to Yes Major NUREG-0313, Rev. 1 IV.B.I.a.(2) Does not meet NUREG-0313, Yes Major Rev. 1 IV.8.1.b. Does not meet NUREG-0313, No Minor Rev. 1 IV.8.1.b.(3) Did not provide data in Yes Minor response to NRC Generic Letter 81-04 IV.B.1.b.(4) Did not provide data in Yes Minor response to NRC Gener.c Letter 81-04 IV.B.2.a. The comments for Parts IV.B.I.a.(1) and IV.B.I.a.(2) apply here. iii l l
Additicnal Part of NUREG-0313 Data Rev. 1 Evaluated Evaluation" Required Discrepancy IV.B.2.b. Does not meet NUREG-0313, No Minor Rev. 1 IV.B.2.b.(6) Did not provide data in Yes Minor response to NRC Generic Letter 81-04 Section V. , aSee Tables 1 and 3 for additional information. bSee Tables 1 and 4 for additional information. i 9 l l e iv
CONTENTS AB ST R AC T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . : . . . . . . 11
SUMMARY
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- 1. I N TR O D UC T I u N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I
- 2. EVALUATION ....................................................... 4 2.1 NUREG-0313, Rev. 1 Guidelines .............................. 4 2.2 Discussion of Tables ....................................... 4 i 2,3 Discrepancies .............................................. 5
- 3. CONCLUSIONS ...................................................... 6
- 4. REFERENCES ....................................................... 34 l
l TABLES Review of Licensee's Respon' e to NRC Generic Letter 81-04 ........
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- 1. s 7
- 2. Sumaries of Evaluation of Licensee's Responses . . . . . . . . . . . . . . . . . . 24 t
- 3. Differences between NUREG-0313, Rev. I and Licensee's Responses....................................................j. .. 26
- 4. Add i tion a l Data Requ ired of Licensee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 l
e V {.. _ _ _ _ _ . . . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ . _ _ . _ _ _ _ _ _
TECHNICAL EVALUATION OF INTEGRITY OF THE COOPER NUCLEAR STATION REACTOR COOLANT B0UNDARY PIPING SYSTEM
- 1. INTRODUCTION Intergranular stress corrosion cracking (IGSCC) of austenitic stainless steel (SS) piping has been observed in boiling water reactors (BWRs) since December 1965.I The NRC established s Pipe Crack Study Group (PCSG) in .lanuary 1975 to study the problem.2 The PCSG issued two documents, NUREG-75/067 Technical Report, Investigation and Evaluation of Cracking in Austenitic Stainless Steel Piping of Boiling Water ReactorsE and an implementation document, NUREG-0313, Rev. 0.2 After cracking in large-diameter piping was discovered for the first time in the Duane Arnold BWR in 1978, a new PCSG was formed. The new PCSG in turn issued two i
reports, NUREG-0531, Investigation 1nd Evaluation of Stress-Corrosion I Cracking in Piping of Light Water Reactor Plants" and NUREG-0313, Rev.1, Technical Report on Material Selection and Processing Guidelines for BWR l Coolant Pressure Boundary Piping.5 h0 REG-0313, Rev. 1 is the . implementing document of NUREG-0531 and discusses the augmented inservice inspection (ISI) and leak detection requirements "for plants that cannot comply with the material selection, testing, and processing guidelines" of NUREG-0313, Rev. 1.5 - NRC Generic Letter 81-04 requested each licensee "to review all ASME l Code Class 1 and 2 pressure boundary piping, safe ends, and fitting material, including weld metal to determine if (they) meet the material
, selection, testing and processing guidelines in" NUREG-0313, Rev. 1.0 The generic letter offered the option of providing a description, schedule, and justification for alternative acticas that would reduce the susceptibility of pressure boundary piping and safe ends to intergranular stress corrosion cracking (IGSCC) or increase the probability of early detection of leakage from pipe cracks.
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In r;sponse to NRC Gen:ric Letter 81-04, Nebraska Public Power District (NPPD)~ submitted a letter on July 1, 1981.7 A request for ' information from the NRC staff elicited another letter from NPPD on December 2, 1932.8 EG&G Idaho personnel evaluated these responses, and this report provides:
- 1. A brief summary of the licensee's response to each part of NUREG-0313, Rev. 1. .
- 2. A discussion of areas where the licensee does not meet the guidelines or requirements of NUREG-0313, Rev. 1.8
- 3. A brief discussion of the licensee's proposed alternatives to NUREG-0313, Rev. 1; however, no determination of acceptability is made on these alteindtives.
4 An identifiedtion of all arear where the licensee has not provided sufficient information to judge the licensee's program. There is an effort underway to revise NUREG-0313, Rev. I by NRC in , lignt of research on IGSCC and recent instances of IGSCC at Nine Mile Paint (March 1982) and Monticello (October 1982). Because of this contemplated revision of NUREG-0313, Rev. 1, the following issues will not be evaluated.
- 1. The-licensee's proposed Tecnnical Specifications to implement the requirements,withtheexcepti$noftheleakdetectionrequirementsin NUREG-0313, Rev.1, Sections IV.B.l.(a)(1) and IV.B.I.(a)(2).
- 2. The acceptability of licensee-proposed augmented inservice inspection (ISI) sampling criteria. ~
- a. Part III of NUREG-0313, Rev. I contains guidelines; Part IV contains requirements.
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, 3. Credit for past op; rating exp;rtence and insp;ction results.
'4 The acceptability of induction heating stress improvement (IHSI), heat ,
sink welding (HSW), and weld overlay as alternates to augmented ISI. iS e.' l l 3
- 2. EVALUATION 2.1 NUREG-0313, Rev. 1 Guidelines The guidelines and requirements outlined in NUREG-0313, Rev. I form the basis of this evaluation. The NUREG-0313, Rev. 1 guidelines are found in Parts III and V and the requirements in Parts II and IV of tnat document. Part II discusses implementation of material selection, testing, and processing guidelines. Part III summarizes acceptable methods to minimize IGSCC susceptibility with respect.to the material selection, testing, and processing guidelines. Part IV deals with leak detection and inservice inspection requirements of nonconforming (i.e., not meeting the guidelines of Part III of NUREG-0313, Rev. 1) piping. Part V discusses general recommendations. -
2.2 Discussion of Tables
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Table 1 has the complete text Parts 11 through V of NUREG-0313, Rev.1 on the left side so that the reader may be able to refer to it as the topics are discussed. The right side summarizes the licensee's responses, lists the differences between the licensee's proposed implementation '
- program and NUREG-0313, Rev.1, and identifies the additional data required
) to evaluate the licensee's response. Many sections in Parts II through IV of NUREG-0313, Rev. I are not discussed in the right hand column. In these cases, one of the comments below will be used. o Not applicable because the construction permit for this plant has been issued. ~ l o Not applicable because the operating license for this plant has been issued. o Not applicable because the plant has been constructed. l l A l l r -m --, ,- - - , ,,.-,-,..n v.,- r. ,. - , ,ra w , , - - - - - - .. ..._ - . . - , , ,m n c, -.--------m--
o Th3 licenses has not furnished data on this topic in his responses to NRC Generic Letter 81-04. o No comment made because alternative plans were not evaluated. Table 2 lists the summaries of the licensee's responses to NRC questions on implementation of NUREG-0313, Rev. I guidelines. Therefore, in Table 2 the reader is able to read all the summaries in one table without having to search Table I for all the summaries. The same compilation applies to Tables 3 and 4. Table 3 lists the differences between the licensee's proposed implementation program and that recommended in NUREG-0313, Rev. 1. Table 4 lists the areas where additional information is required to properly evaluate the licensee's proposed implementation program. All the items in Tables 2, 3, and 4 are listed in their respective tables in the order they appear in Table 1. 2.3' Discrepancies Any alternate proposal that did not meet a specific guideline or requirement of NUREG-0313, Rev. I was considered a discrepancy. Evaluation of alternate proposals was outside the scope of this task, as indicated in Section 1 of this report. Licensees have submitted definitions of "nonservice sensitive" and augmented ISI proposals that differ from NUREG-0313, Rev. l'. These differences are considered minor because the NRC staff is considering major modifications to those requirements. An example of a minor discrepancy is the use of the stress rule index (SRI) to choose which welds would be subjected to augmented 'SI.
, If the alternate proposal to leak detection does not meet the requirements in NUREG-0313, Rev.1, it was considered a major discrepancy because NRC is~ not considering major modifications to those requirements. !
An example of a major discrepancy is a licensee's not proposing Technical Specifications to implement leak detection requirements in NUREG-0313, l Rev. 1. Only major discrepancies are listed in the Conclusions section. 5
- 3. CONCLUSIONS The major discrepancies for Cooper consist of the following:
Part IV.B.I.a.(1)-Leak Detection and Monitoring NPPD's description of Cooper's leak detection methods is not - detailed enough to determine whether they meet Section C of Regulatory Guide 1.45. Part IV.B.I.a.(2) Shutdown for Leakage NPPD has not proposed a requirement for shutdown after a 2-gpin increase in unidentified leakage in 24 h into the Technical Specifications for Cooper. NPPD has not proposed a requirement for monitoring the sump level at 4-h intervals (or less). NPPD does not meet NUREG-0313, Rev. 1 in this matter. ' There are minor discrepancies as well as the major ones listed above. These minor discrepancies'are not listed here. However, while the licensee's alternate proposals that have been classified as minor discrepancies might be acceptable under the anticipated revision of NUREG-0313, Rev.1, it should not be inferred that approval of those alternate proposals has been given. The licensee has not supplied sufficient information to evaluate his responses to topics II.C., IV.B.I.a.(1) and (2), IV.B.I.b.(3) and (4), IV.B.2.a., and IV.B.2.b.(6). Table 4 lists the required information for each topic. 6
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TABLE 1. REVIEW OF LICENSEE'S RESPONSE 10 NRC GENERIC LEilER 81-04 Excerpts from NUREG-0313. Rev. I EG&G Idaho Evaluation--COOPER NUCLEAR STATION II. IMPLEMENTATION OF MATERIAL SELECTION, TESilNG, AND PROCESSING GUIDELINES II.A. For plants under review, but for which a A. Not applicable because the construction permit for this construction permit has not been issued, all ASME plant has been issued. Code Class 1, 2, and 3 lines should conform to the 9uldelines stated in Part III. II.B. For plaats tnat have been issued a construction 8. Not applicable because the operating license for this permit but not an operating Ilcense, all ASME Code plant has been issued. Class 1, 2, and 3 lines should conform to the guidelines stated in Part Ill unless it can be demonstrated to the staff that iglementing the guidelines of Part III would result in undue haroship. For cases in which the guidelines of Part III are not complied with, additional measures should be taken for Class I and 2 lines in accordance with the gu melines stated in Part IV of this document. + ll.C. For plants that have been issued an operating C. SLMMARY
" license, NRC designated " Service Sensitive" lines (Part IV. 8) should be modified to conform to the NPPD has indicated they do not plan to replace any 9uldelines stated in Part III, to the extent " service sensitive" pipe cracked by intergranular 3 tress practicable. When " Service Sensitive" and other corrosion. NPPD has provided an alternative to NUREG-0313, Class 1 and 2 lines do not meet the guidelines of Rev. I.
Part Ill, additional measures should be taken in accordance with the guidelines strted in Part IV DIFFERENCES of this document. Lines that experience cracking during service and require replacement should be NUREG-0313, Rev. I requires that nonconforming replaced with piping that conforms to the NRC-designated " service sensitive" lines be replaced with guidelines stated in Part 111. corrosion-resistant materials. Also lines that experience cracking should be replaced with carrosion-resistant materials. NPPD has indicated t ' " service sensitive" pipe. gatHowever they doNPPD not plan has to notreplace any indicated what they will do with cracked " service sensitive" pipe.
, .. ADDITIONAL DATA REQUIRED Indicate wnat actions will be taken if any " service sensitive" piping is found to suffer any intergranular stress corrosion cracking (IGSCC).
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Ill. SupptAR) 0F ACCEPTABLE METHODS TO MINIMIZE CRACK SUSCEPTIBILIIY--MATERI AL SELECTION, TESTING, AND FlIUCE55ING GU!DELINES Ill.A. Selection of Materials A. The licensee has not furnished data on this paragraph in his responses to NRC Generic Letter 81-04. See Only those materials described in Paragraphs 1 comument on Part II.C. above. and 2 below are acceptable to the NRC for installation in BWR ASME Code Class I, 2, and 3 piping systems. Other materials may be used when evalested and accepted by the NRC. III.A.I. L erosion-Resistant Materials 1. The cosuments on III.A. also apply here. All pips and fitting material including safe ends, thermal sleeves, and weld metal should be of a type and grade that has been demonstrated to be highly resistant to oxygen-assisted stress corrosion in the as-installed condition. Materials that have been so demonstrated include ferritic steels.
" Nuclear Grade" austenitic stainless steels
- Types 304L and 316L austenttic stainless steels, Type CF-3 cast stainless steel.
Types CF-8 and CF-SM cast austenttic stainless steel with at least 5% ferrite, Type 308L stainless steel weld metal, and other v, austenttic stainless steel weld metal with at ' CD least 5% ferrite content. Unstabilized wrought austenttic stainless steel without controlled low carbon has not been so demonstrated except when the piping is in the solution-annealed condition. The use of such material (l.s., regular grades of Types 304 and 3M stainless steels) should be evolded. If such material is used, the as-installed piping including welds should be in the solution-annealed condition. Where regular grades of Types .304 and 316 are used and welding or heat treatment is required, special measures, such as those described in Part III.C. Processing of Materials, should be taken to ensure that IGSCC will not occur. Such measures may include (a) solution annealing subsequent to the welding or heat treatment, and (b) weld cladding of materials to be welded using procedures that have been demonstrated to reduce residual stresses and sensitization of surface materials. e .
- These materials have controlled Icw carbon (0.02% max) and nitrogen (0.1% ma;) c)ntents and meet all requirements, including mechanical property requirements, of ASME specification for regular grades of Type 304 or
- 316 stainless steel pipe.
r - III.A.2. Corrosion-Resistant Safe Ends and Thermal 2. The comments on III.A. also apply here. Sleeves All unstabilized wrought austenttic stainless steel materials used for safe ends and thermal sleeves without controlled low carbon contents (L-grades and Nuclear Grade) should be in the solution-annealed condition. If as a consequence of f abrication, welds joining these mater als are not solution annealed, th?y should be made between cast (or weld overlaid) austenttic stainless steel surf aces (5% minimum ferrite) or other materials having - high resistance to oxygen-assisted stress corrosion. The joint design must be such that any high-stress areas in unstabilized wrought austenitic stainless steel without controlled low carbon content, which may become sensitized as a result of the welding process, is not exposed to the reactor coolant. Thermal sleeve attachments that are welded to the pressure boundary and form crevices where t impurities may accumulate should not be - exposed to a 8WR coolant environment. III.8. Testing of Materials 8. The Ifetasee has not furnished data on this paragraph in his responses to NRC Generic Letter 81-04. For new installatice, tests should be made on all us regular grade stainiess steels to be used in the ASNE Coje Class 1. ?, and 3 piping systems to demonstrate that the material was properly annealed and is not susceptible to IGSCC. Tests that have been used to determine the susceptibility of IGSCC include Practices A* and E** of ASTM A-262, "Reconnended Practices for Detecting Susceptibility to Intergranular Attack in Stainless Steels" and the el,ctrochemical potentiokinetic reactivation (EPR) test. The EPR test is not yet accepted by the NRC. If the EPR test is used, the acceptance criteria applied must be evaluated and accepted by the NRC on a case-by-case basis. e .
- Practice A--0xalic acid etch test for classification of etch structures of stainless steels.
! ** Practice E--Copper-copper sulf ate-sulfuric acid test for detecting susceptibility to intergranular attack in stainless steels.
- Ill.C. Processing of Mattrials C. The licensee has n:t ftrnis4ed data on this parsgraph in his responses to NRC Generic Letter 81-04. See Corrosion-resistant cladding with a duplex comunent on Part II.C. above.
microstructure (55 minimum ferrite) may be applied to the ends of Type 304 or.316 stainless steel pipe for the purpose of avoiding IGSCC at weldments. Such cladding, which is intended to (a) minimize the HAZ on the pipe inner surf ace, (b) move the HAZ away from the highly stressed region next to the attachment weld, and (c) Isolate the weldsent from the environment, may be applied under the f ollowing conditions: III.C.1. For initial construction, provided that all of I. Th3 comuments on III.C. also apply here. the piping is solution annealed af ter cladding. III.C.2. For repair welding and modification to 2. The comuments on III.C. also apply here. in-place systems in operating plants and plants under construction. When the repair welding or modification requires replacement of pipe, the replacement pipe should be solution-annealed after cladding. Corrosion-resistant cladding app 11ed in the
" field" (i.e., without subsequent solution annealing of the pipe) is acceptable only on that portion of the pipe that has not been removed from the piping system. Other " field" ,
y applications of corrosion. resistant cladding i o are not acceptable. Other processes that have been found by laboratory tests to minialie stresses and IGSCC in austenitic stainless steel weldsents include induction heating stress improvement (IHSI)andheatsinkwelding(HSW). Although the use of these processes as an alternate to aegmented inservice inspection is not yet accepted by the NRC, these processes may be 4 permissible and will be considered on a case-by-case basis provided acceptable supportive data are submitted to the NRC. I V. INSERVICE INSPECTION AND LEAK DETECTION REQUIREMENTS FOR EWRs WITH VARYING DEGRROF CONFORMANCE TO NATERIAL SELECTION, IESTING, AliU PROCESSING GUIDELINES IV.A. For plants whose ASME Code Class 1, 2, and 3 A. The licensee has not furnished data on this paragraph pressure boundary piping meets the guidelines of in his responses to NRC Generic Letter 81-04. Part III, no augmented inservice inspection or , . leak detection requirements beyond those specified in the 10 CFR 50.55a(g), " Inservice Inspe: tion Requirements
- and plant Technical Specifications for leakage detection are necessary.
IV.B. ASME Code Class 1 and 2 pressure boundary piping B. The licensee has not furnished data on this paragraph that does not meet guidelines of Part III is in his responses to NRC Generic tetter 81-04. designated
- Nonconforming" and must have additional inservice inspection and more stringent leak detection requirements. The degree of augmented inservice inspection of such piping depends on whether the specific " Nonconforming" piping runs are classified as " Service Sensitive." The " Service Sensitive" lines were and will be designated by the NRC and are refined as those that have experienced cracking of a generic nature, or that are considered to be particularly susceptible to cracking because of a combination of high local stress, material 4
condition, and high oxygen content in the relatively st agnant, intermittent, or law-f' ow coolant. C;.: .ently, for the nonconforming LSME Code Class 3 piping, no additional inservice inspection beyond the Section XI visual examination is required. Examples of piping considered to be " Service . Sensitive" include but are not limited to: core spray lines, recirculation riser lines,* recirculation bypass lines (or pipe ' extensions / stub tubes on plants where the bypass lines have been removed), control rod drive (CRD) hydraulic return lines, isolation condenser lines, g recirculation inlet lines at safe ends where H crevices are formed by the welded thermal sleeve attachments, and shutdown heat exchanger lines. If cracking should later be found in a particular , piping run and censidered to be generic, it will be designated by the NRC as " Service Sensitive."
*Since no IGSCC has been observed in the domestic plants and in view of the possible high radiation exposure to the inspection personnel, surveillance and monitoring means other than those specified in Section IV of this report for ,
recirculation riser lines will be considered on a case-by-case basis. Leakage detection and augmented inservice inspection requirements for " Nonconforming" lines # and " Nonconforming, Service Sensitive" lines are -' specified below: IV.8.1. " Nonconforming" Lines That Are Not " Service a 5ensitive"
7 IV.B.1.a. Leak Detection: The reactor coolant leakage detection systems should be operated under the Technical Specification requirements to enhance the discovery of unidentified leakage that may include through-wall cracks developed in austenitic stainless steel ofping. IV.8.1.a.(1) The leakage detection system provided (1) StM4ARY should include sufficiently diverse leak detection methods with adequate NPPD's description of Cooper's leak detection methods sensitivity to detect and measure small is not detailed enough to deterrine whether they meet leaks in a timely manner and to identify Section C of Regulatory Guide 1.45. the leakage Jources within the practical limits. Acceptable leakage detection and DIFFERENCES monitoring systems are described in Section C, Regulatory Position of . The nine subsections of Section C of kegulatory Regulatory Guide 1.4:, " Reactor Coolant Guide 1.45 are discussed below. Pressure Boundary Leakage Detection Systems." C.1 IE has stated that leakage to the primary reactor containment from identified sources is collected Particular attention should be given to such that upgrading and calibrating those leak detection systems that will provide prompt a. indication of an increase in leakage rate. the flow rates ontdentified are g itored leakage, and separately from C Other equivalent leakage detection and b. collection systems will be reviewed on a 9the total {Iow rate Can be established and monitored. case-by-case basis. C.2 The unidentified leakage in Cooper to the primary reactor containment can be collected and the flow . rate monitored with an accuracy of 1 gpm or better.8,9 C.3 The leak detection and monitoring systems employed by NPPD at Cocper consist of:
- a. Drywell equipment and floor drain sump flow recorders,
- b. Drywell equipment sump temperature indicator,
- c. Three suppression pool water level indicators and one recorder,
- d. Three primary Containment and one wetwell pressure indicators.
* .. e. Primary containment internal temperature and wetwell pool temperature.
- f. Drywell process radiation from monitor.8 From the above, it is not known whether Cooper has all the leak detection and monitoring methods ,
reconsnended by Section C.3 of Regulatory . Guide 1.45. d
C.4 It is not clear whether prCvisions have been made in the Cooper FSAR to monitor systees connected to the RCPB for signs of intersystem leakage. C.5 It is not clear that the Cooper leakage detection and monitoring systems employed for unidentified leakage are adequate to detect a leakage rate of I goe in less than I h. C.6 The Cooper airborne particulate radioactivity monitoring system reagins functional when subjected to the SSE.o C.7 Indicators and alarms for the required leakage detection system are provided in the main control room. Procedures for converting various indications to a common leakage equivalent are available to the operators.9 It is not known whether calibration of the indicators accounts for the needed independent variables. . C.8 Ai1 Cooper leak detection systems enumerated in (leference 8 can be calibrated or tested during operation. y w C.9 The Cooper Technical Specifications include limiting conditions f unidentified leakage.gr D identified and NPPD has identified the availability of the Cooper systems for detecting and monitoring leakage. Two of the three systems
- a. Sump flow measuring sys' ens
- b. Containment atmospheric radiation monitor, or
- c. Containment atmospheric samp1tng systems
, , are always available.10 It cannot be determined from the above wwther Cooper meets Regulatory Guide 1.45, Section C.
, , AD0!TIONAL DATA REQUIRED
- 1. Indicate whether provisions have been made in the Cooper FSAR to monitor systems connected to the RCPB for signs of intersystem leakage (Subsection C.4 of Regulatory Guide 1.45).
- 2. Indicate whether calibration of the indicators accounts for the needed independent variables (Subsection C.7 of Regulatory Guide 1.45).
- 3. Indicat1r whether the Cooper Irak detection and monitoring methods include airborne particulate radioactivity monitoring, condensate flow rate from air coolers monitoring, and airborne gaseous radioactivity monitoring (Subsection C.3 of Regulatory Guide 1.45).
4 Indicate whether the Cooper leakage detection and -- monitoring systems employed for unidentified leakage can detect a 1-gpa leak in I h (Subsection C.5 of Regulatory Guide 1.45). IV.B.I.a.(2) Plant shutdown should be initiated for ' (2) St# MAR Y inspection and corrective action when any leatage detection system indicates, within NPPD has not proposed a requirement for shutdown after a period of 24 hours or less, an increase c 2-gpa increase in unidentified leakage in 24 h into in rate of unidentified leatage in excess the Technical Specifications for Cooper. of 2 gallons per minute or its equivalent, or when tTe total unidentified leakage NPPD has not proposed a requirement for monitoring the attains a rate of 5 gallons per minute or sump level at 4-h intervals (or less). Its equivalent, whichever occurs first. For sump level monitoring systems with NPPD does not meet NUREG-0313, Rev. I in this matttr. fixed-measurement interval method, the level should be monitored at 4-hour DIFFERENCES intervals or less. - NtREG-0313. Rev. I requires that reactor shutdown be
% initiated when there is a 2-gpa increase in unidentified leakage in 24 h. For sump level monitoring systems with the fixed-neasurement interval method, the level should be monitored every 4 h or less.
NPPD has not l'Korporated the provision for shutdown for a 2 gpa increase in unidentified leak.ve in 24 h into the Cooper Technical Specifications. Also, according to the Cooper Technical Specifications, the sump and air sampilng leak detec monitored at least once per day.gion systems are ADDITIONAL DATA REQUIRED None. IV.B.I.a.(3) Unidentified leakage should include all (3) NPPD's definition of unidentified laakage for Cooper leakage other than: meets NUREG-0313 Rev. 1 (FSAR Section 10.3). IV.B.I.a.(3)(a) Leakage into closed systess, such as (a) The comments on IV.B.I a.(3) also apply here. pump seal or valve packing leaks that are captured, flow metered, and ' - conducted to a sump or collecting tant, or 4 4
i , , I V.8. l . a. ( 3)(b ) Leakage into the Containmenit (b) The conuments on IV.8.l.a.(3) also apply here. atmosphere from sources that are both specifically located and taown either not to interfere with the operations of unidentified leakage monitoring systems or not to be from a through-wall cract in the elping within the reactor coolant pressure boundary. I V. 8. l .a. Augmented Inservice Inspection: Inservice b. NPPD " considers all nonconforming stainless stee inspection of the " Nonconforming, primary coolant piping to be service sensitive'.g honservice Sensitive" lines should be The consnents on Part IV.8.2.b. also apply here. conducted in accordance with the follo'ving program:*
*This program is largely taken from the requirements of ASME i Boiler & Pressure Vessel Code, Section XI, referenced in the paragraph (b) of 10 CFR 50.55a. " Codes and Standards.*
IV.8.1.b.(1) For ASME Code Class I components and (1) The conssents on IV.B.I.b. also apply here. piping, each pressure-retaining dissimilar ., metal weld subject to inservice inspection ' requirements of Section XI should be
- examined at least once in no more than cn 80 months (two-thirds of the time prescribed in the ASME Boller and Pressure Vessel Code Section XI). Such examination should include all internal attachment welds that are not through-wall welds but are welded to or form part of the pressure boundary.
I V. 8.1.b . ( 2) The following ASME Code Class I pipe welds (2) The consnents on IV.8.1.b. also apply here. subject to inservice inspection . requirements of Section XI should be examined at least once in no more than 80 months: IV.B.I b.(2)(a) All welds at terminal ends
- of pipe (a) The comuments on IV.B.I.D. also apply here.
at vessel nozzles; i
- Terminal ends are the extremities of piping runs that '*
connect to structures, components (such as vessels, pumps, valves) or pipe anchors, each of which acts as rigid restraints or provides at least two degrees of restraint to piping thermal expansion. I V. 8.1.b . ( 2)(b) All welds having a design combined (b) The consnents on IV.8.1.b. also apply here. primary plus secondary stress range of 2.45, or more;
I V.B. I .b. ( 2) (c ) All welds hning a design cumulative (c) The coasnents on IV.B.I.b. also apply hero, f atigue usage factor of 0.4 or more; and I V.B. I .O. (2)(d) Sufficient edditional welds with hign (d) The comunents on IV.B.I.b. also apply here. potential for cracking to make the total equal to 255 of the welds in each piping system. I V. 8. I .b. ( 3) The following ASME Code Class 2 pipe (3) StMMARY welds, subject to inservice inspection requirements of Section XI, in residual NPPD has not identified those nonconforming "nonservice heat removal systems, emergency core sensitive" pipes which are to be inspected per Part cooling systems, and containment heat IV.B.I.b.(3) of NUREG-0313 Rev.1. Data are needed to removal systems should be examf ned at determine which "nonservice sensitive" ASME Code Class 2 least once in no more than 80 months: pipes will be inspected and what inspection procedures will be used. DIFFERENCES NUREG-0313. Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an augmented ISI program. The augmented ISI program for ASME Code Class 1 piping differs from that required on Class 2 p ip t'ig. Also,' augmented ISI requirements differ for ASME ' Code Class 2 pipes to be inspected per Parts IV.B.I.b.(3) cn and IV.B. I.b.(4) of NUREG-0313, Rev.1. NPPD has submitted the augmented 151 program for nonconforming "nonservice sensitive" piping, but has not distinguished between the ASME Code Class I and Class 2 piping, and between the ASME Code Class 2 pipes which are to be inspected per Parts IV.B.I.b.(3) and IV.B.I.b.(4) of NUREG-0313, Rev.1. Therefore, NPPD's program for ASME Code Class 2 piping cannot be evaluated. ADDITIONAL DATA REQUIRED Identify which ASME Code Class 2 pipe will be inspected per Part IV.B.I.b.(3) and which inspection procedures will be used. IV.B.I,b.(3)(a) All welds of tne terminal ends of (a) The conuments on IV.B.I.b.(3) also apply nere. pipe at vessel nozzles, and IV.B.I.b.(3)(b) At least los of the welds selected (b) The conuments on IV.B.I.b.(3) also apply here. proportionately from tne following categories: e .. I V.B. I .O. ( 3)(b)( 1) Circuaterential welds at (t) The consments on IV.B.I.b.(3) also apply here. locations where the stresses
- under the loadings resulting from calcu_any, plant iated by theconditions sum of as Equations (9) and (10) in .
NC-3652 exceed 0.8 (1.2Sn
- SA Ii
IV.B.I.D.(3)(b)(tt) Welds at terminal ends of (11) The comments on IV.B.I.b.(3) also apply here. piping, including branch runs; IV.B.I.b.(3)(b)(lii) Dissiellar metal welds; (ill)The comments on IV.B.I.b.(3) also apply here. IV.B.I.O.(3)(b)(iv) Welds at structural (iv) The couments on IV.B.I.b.(1) also apply here. discontinuities; and IV.B.I.b.(3)(b)(v) Welds that cannot be pressure (v) The comments on IV.B.I.b.(3) also apply here. tested in accordance with IWC-5000. The welds to be examined shall be distributed approximately equally among runs (or portions - of runs) that are essentially similar in design, size, system function, and service conditions. I V.B. I .b. (4) The following ASME Code Class 2 pipe (4)
SUMMARY
welds in systems other than residual heat removal systems, emergency Core NPPD has not identified those nonconformi'ng "nonservice cooling systems, and containment heat sensitive' pipes which are to be inspected per Part removal systems, which are subject to IV.B.I.b.(4) of NUREG-0313, Rev.1. Data are needed to inservice inspection requirements of determine which "nonservice sensitive" ASME Code Class 2 Section XI, should be inspected at pipes will be inspected and what inspection procedures will j least once in no more than 80 months: be used. DIFFERENCES NUREG-0313, Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an augmented ISI program. The augmented ISI program for ASME Code Class 1 piping differs from that required on Class 2 piping. Also, augmented 151 requirements differ for ASME Code Class 2 pipes to be inspected per Parts IV.B.I.b.(3) and IV.B.I.b.(4) of NUREG-0313, Rev.1. NPPD has submitted the augmented ISI program for nonconforming "nonservice sensitive
- piping, but has not distinguished between the ASME Code Class I and Class 2 piping, and between the ASME Code Class 2 pipes which are to be inspected per Parts IV.B.I.b.(3) and IV.B.1.b.(4) of NUREG-0313, Rev.1. Therefore, NPPD's program for ASME Code Class 2 piping cannot be evaluated.
e .. ADDITIONAL DATA REQUIRED Identify which ASME Code Class 2 pipe will be inspected per Part IV.B.I.b.(4) and which inspection procedures will be used.
IV.B.I.b.(4)(a) All welds at locations whtre the (a) The comments or: IV.B. I.b.(4) alsD (pply here. str:ssis under the Icatings resulting from " Normal" and "Uoset" plant conditions including the operating basis earthquake (08E) as calculated by the sum of Equations (9) and (10) , in NC-3652 exceed 0.8 (1.2Sn + Sg); I V. B. I . b. ( 4 ) (b) All welds at terminal ends of piping, (b) The comuments on IV.B.I.b.(4) also apply here. including branch runs; I V.B. l.b. ( 4)(c) All dissiellar metal welds; (c) The comuments on IV.B.I.b.(4) also apply here. -- IV.B.I.b.(4)(d) Additional welds with high potential (d) The comuments on IV.B.I.b.(4) also apply here. 4 for cracking at structural ' discontinuities
- such that the total /
number of welds selected for examination equal to 25% of the " '$ circumferential welds in each piping system.
- Structural discontinuities include pipe weld joints to vessel nozzles, valve bodies, pump casings, pipe fitting:
(sucn as elbows, tees, reducers, flanges, etc., conforming to ANSI Standard B 16.9) and pipe branch connections and , co fittings.
'(
I V. B. I .b. (5) If axamination of (1), (2), (3), and (5) The comments on IV.B.I.b.(1), (2), (3), and (4) also (4) above conducted during the first apply here. 80 months reveal no incidence of stress corrosion cracking, the - examination frequency thereaf ter can revert to 120 months as prescribed in Section XI of the ASME Boller and Pressure Vessel Code. ' IV.B.I.b.(6) Sampling plans other than those (6) No coronent made because alternative plans were not described in (2), (3), and (4) above evaluated. will be reviewed on a case-by-case basis. I V. 8. 2. " Nonconforming" Lines That are " Service 5ensitive" IV.B.2.a. teak Detection: The leakage detection a. requirements, described in IV.P.1.a. Tne comunents made in Parts IV.B.I.a.(1) and
- IV.B.I.a.(2) apply here.
above, should be implemented. #
- _. .. - . .. ~.. ._ ..
~
t IV.B.2.b. Augmented Inservice Inspection: b.
SUMMARY
NPPD has provided some data on the augmented ISI prograg for all nonconforming stainless steel piping. NPPD's propcsed augmented ISI plani do not meet NURES-0313 Rev. 1. DIFFERENCES NUREG-0313 Rev. I requires that ASME Code Class 1
- service sensitive" pipes be subject to an augmented ISI program. Selection methods for pipes to be examined and other technical details are found in Part IV.8.2.b. of NUREG-0313. Rev.1.
NPPD is examining nonconforming " service sensitive
- piping per the guidelines set forth in General Electric's Service Infgnmation Letter (SIL) No.117. Rev.1 March 1976.8 Some details of SIL 117 are below.
Piping Systems Extent of Examination Recirculation Bypass 100% of welds Core Spray ; System 100% of welds RHR Shutdown Cooling 100% of welds in one loop [$ Recirculation System Select welds per ASME Section II, 1W4 Edition. Summer 1975 Addenda. Welds selected to be examined should be completed during the first 80-month period. For the balance of plant service lifetime, examination - shall revert to the schedule in ASME Section XI. Inservice inspection of- These examinations should be austenttic stainless conducted in accordance with the steel pipe runs within schedule specified in ASME Code, the reactor coolant Section XI--Subsection IWB, as boundary that operate required by the applicable flow with full coolant (RWCU) categories B-F and 8-J. with the r during normal reactor exception that the required operat ion. examinations be completed during
-* the first 90 month period. After the first 80-month period the examinations shall revert back to the ASME Section schedule.
The extent of examination for the RHR shutdown cooling . . and recirculation system does not meet NUREG-0313. Pev.1. ADDITIONAL DATA REQUIRED None.
_. Ay e IV.B.2.b.(1) The welds and adjoining areas of (1) The conrents on IV.B.2.b. also apply her2. bypass pipit.g of the discnarge valves in the main recirculation loops, and of the austenttic stainless steel reactor core spray piping up t, and including the second isolation valve, should be examined at each reactor refueling outage or at other scheduled plant outages. Successive examination need not be closer than 6 months, if outages occur more frequently than 6 months. This requirement applies to all welds in all bypass lines whether the 4-inch valve is kept open or closed during operation. In the event these examinations find the piping free of unacceptable indications for three successive inspections, the examination may be extended to eacn 36-month period (plus or minus by as much as 12 mcnths) coincident with a refueling outage. In these cases, , the successive ee nmination may be ro limited to all n 'ds in one bypass o pipe run and one reactor core spray
'. t piping run. If unacceptable flaw indications are detected, the remaining piping runs in each group should be examined.
Ie, the event these 36-month period examinations reveal no unacceptable indications for three successive inspections, the welds and adjoining areas of these piping runs should be examined as described in IV.B.I.b(1) for dissimilar metal welds and in IV.B.I.b(2) for other welds. . I V. B. 2. b . ( 2) The dissimilar metal welds and (2) The licensee has not furnished data on this paragraph adjoining areas of other ASME Code in his responses to NRC Generic Letter 81-04. 4 Class 1 " Service Sensitive" piping should be examined at each reactor refueling outage or et other scheduled plant outages. Successive examinations need not be closer than ,, -, 6 months, if outages occur more f requently than 6 months. Such examination should include all internal attachments that are not througa-wall welds but are welded to or fora part of the pressure boundary. *
* ~ '
IV.B.2.b.(3) The welds and adjoining areas of (3) The coninents on IV.B.2.b. also apply here. other ASME Code Class 1 " Service Sensitive" piping should be examined using the rampling plan described in IV.B.I.b(2) except that the frequency of such examinations should be at each reactor refueling outage or at other schedaled plant outages. Successive examinations need not be closer than 6 months, if outages occur more frequently than 6 months. IV.8.2.b.(4) The adjoining areas of internal (4) The cocinents on IV.B.2.b. also apply here. attachment welds in recirculation inlet lines at safe ends where crevices are formed by the wilded thermal sleeve attachment should be examined at each reactor refueling mutage or at other Scheduled plant outages. Successive examinations need not be closer than 6 mont5s, if outages occur more frequently than 6 months. , I V.B. 2.0. ( 5 ) In the event the examinations (5) The comments on IV.B.2.b. also apply here. l described in (2), (3) and (4) above N find the piping free of unacceptable indications for three successive inspections, the examination may be extended to each 36-month period (plus or minus by as much as 12 months) coinciding with a refueling outage. In the event these 36-month period l examinations reveal no unacceptable indications for three successive inspections, the frequency of examination may revert to 80-month periods (two-thirds the time [ rescribed in the ASME Code Section XI). I V. B. 2.b. ( 6) The area, extent, and frequency of (6) SlM1AR Y examination of the augmented inservice inspection for ASME Code NPPD has submitted the augmented ISI program for
" .aonconforming " service sensitive" piping, but has not Class 2 " Service Sensitive" lines will be determined on a case-by-case distinguished between the ASME Co<te Class 1 and Class 2 basis. piping. Therefore, NPPD's program for ASME Code Class 2 piping cannot be evaluated without more data.
DIFFERENCES NUREG-0313 Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an augmented ISI program. The augmented ISI 1rogram for ASME Code Class 1 piping differs from that required on Class 2 piping.
C' PPD has not idextified those ronccafusing "sIrvic2 sensitive" pipes which are to be inspected per Part IV.8.2.b.(6) of NUREG-Oll3, Rev.1. Data are needed to determine tvnich " service sensitive" ASME Code Class 2 pipes will be inspected and what in , tion procedures will be used. ADDITIONAL DATA REQUIRED i
- 1. Identify which ASME tode Class 2 pipe will be '
inspected per Part IV.B.2.b.(6).
- 2. Identify the inspection procedures for " service sensitive" ASME Code Class 2 pipe. !
. IV.R.3. Nondestructive Examination (NDE) Requirements 3. The licensee has not furnished data on this paragraph j in his responses to NRC Generic Letter 81-04. t ine method of examination and volume of material to be examined, the allcwable indication standards, and examination procedures should comply with the requirements set forth in the applicable Edition and Addenda of the ASME Code, )
4 Section XI, specified in Paragraph (g), j
" Inservice Inspection Requirements," of 10 CFR l 50.55a " Codes and Standards."
N t N In some cases, the code examination procedures may not be effective for detecting or evaluating IGSCC and other ultrasonic (UT) procedures or advanced nondestructive examination techniques may be required to detect and evaluate stress corrosion cracking in austenitic stainless steel piping. Iciproved Uf procedures have been developed by certain organizations. These improved UT detection and evaluation procedures that have been or can be demonstrated to the NRC , to be ef fective in detecting IGSCC should be used in the inservice inspection. Recomendations for the development and eventual l Implementation of these improved techniques are included in Part V. V. GENERAL RELOMMENDAil0NS V. No coment made because alternative plans were not evaluated. The measures outlined in Part III of this document provide for positive actions that are consistent with current technology. Tne implementation of these actions ', should markedly reduce the susceptibility of stainless
- steel piping to stress corrosion cracking in BWRs. It is recognized that additional means could be used to limit the extent of stress corrosion cracking of BWR i
pressure boundary piping materials and to ' improve the overall system integrity. These I include plant design and operational procedure considerations to reduce system exposure to potentially aggressive environment, improved material selection, special fabrication and l welding techniques, and provisions for volumetric inspection capability in the design of weld joints. The use of such means to limit IGSCC or to improve plant system integrity will, be reviewed on a case-by-case basis. , l 1 i 4 LJ 1 e l l l I l 1 _ . _ _ _ . - _ _ - _ _ _. ,- . _
. .. . .. =. . . . .. .-. .. . .. . - . .. . . . .. .
TABLE 2 SUMMARIES OF EVALUATION OF LICENSEE'S RESPONSES II.C Material Selection, Testing, and Processing Guidelines for BWRs with l an Operating License NPPD has indicated they do not plan to replace any " service sensitive" pipe cracked by intergranular stress corrosion. NPPD has provided an alternative to NUREG-0313, Rev. 1. IV.B.l.a.(1) Leak Detection and Monitoring Systems 3 NPPD's description of Cooper's leak detection methods is not
~
detailed anough to determine whether tney meet Section C of Regulatory Guide 1.45. IV.B.I.a.(2) leak Detection Requirements ,' , NPPD has not proposed a requirement for shutdown after a 2-gpm increase in unidentified leakage in 24 h into the Technical Specifications for Cooper. NPPD has not proposed a requirement for monitoring the sump level at 4-hintervals(orless). NPPD does not meet NUREG-0313, Rev.1 in this matter. IV.B.I.b.(3) Augmented ISI of Nonconforming "Nonservice Sensitive" ASME Code Class 2 Pipe NPPD has not identified those nonconforming "nonservice sensitive" pipes which are to be insnected per Part IV.B.l.b.(3) of NUREG-0313, 24
Rev. 1. Data are needed to determine which "nonservice sensitive" ASME Code Class 2 pipes will be inspected and what inspection procedures will be used. IV.B.I.b.(4) Augmented ISI of Nonconforming "Nonservice Sensitive" ASME Code Class 2 Pipe NPPD has.not identified those nonconforming "nonservice sensitive" pipes which are to be inspected per Part IV.B.l.b.(4) of NUREG-0313, Rev. 1. Data are needed to determine which "nonservice sensitive"
~
-{
ASME Code Class 2 pipes will be inspected and what inspection - I procedures will be used. IV.B.2.b. Augmented ISI of Nonconforming " Service Sensitive" Pipe
- )
NPPDhasprovidedsomedata$ntheaugmentedISIprogramforall nonconforming stainless steel piping. NPPD's proposed augmented ISI plans do not meet NUREG-0313, Rev.1. t i IV.B.2.b.(6) Augmented ISI of Nonconforming " Service Sensitive" ASME Code l Class 2 Pipe NPPD has submitted the augmented ISI program for nonconforming i
" service sensitive" piping, but has not distinguished between the ASME Code Class 1 and Class 2 piping. Therefore, NPPD's program for l
ASME Code Class 2 piping cannot be evaluated without more data. 25
TABLE 3 DIFFERENCES BETWEEN NUREG-0313, REV.1 AND LICENSEE'S RESPONSES II.C Material Selection, Testing, and Processing Guidelines for BWRs with an Operating License - NUREG-0313, Rev. I requires that nonconforming NRC-designated .
" service sensitive" lines be replaced with corrosion-resistant materials. Also lines that experience cracking should be replaced with corrosion-resistant materials.
NPPD has indicated that they do not plan to replace any " service
; sensitive" pipe. However,.NPPD has not indicated what they will do with cracked " service Tensitive" pipe.
IV.B.I.a.(1) Leak Detection and Monitoring Systems The nine subsections of Section C of Regulatory Guide 1.45 arei discussed below. C.1 IE has stated that leakage to the primary reactor containment from identified sourcas is collected such that
- a. the flow rates are monitored separately from unidentified leakage, and t' . the total flow rate can be established and monitored.9 C.2 The unidentified leakage in Cooper to the primary reactor containment can be collected and the flow rate monitored with an accuracy of I gpm or better.0'9 26
C.3 The leak detection and monitoring systems employed by NPPD at Cooper consist of:
- a. Drywell equipment and floor drain sump flow recorders.
- b. Drywell equipment sump temperature indicator.
1'
- c. Three suppression pool water level indicators and one recorder.
- d. Three primary containment and one wetwell pressure indicators.
- e. Primary containinent internal temperature and wetwell
; pool temperature.
- f. Drywell process radiation from monitor.0 From the above, it is not known whether Cooper has aTl the leak detection and monitoring methods recommended by Section C.3 of Regulatory Guide 1.45.
C.4 It is not clear whether provisions have been made in the Cooper FSAR to monitor systems connected to the RCPB for signs of intersystem leakage. C.5 It is not clear that the Cooper leakage detection and monitoring systems employed for unidentified leakage are adequate to detect a leakage rate of 1 gpm in less than I h. C.6 The Cooper airborne particulate radioactivity monitoring system remains functional when subjected to the SSE.8 C.7 Indicators and alarms for the required leakage detection system are provided in the main control room. Procedures 27 m
for converting various indications to a common Icakage equivalent are available to the operators.9 It is not known whether calibration of the indicators accounts for the needed independent variables. C.8 All Cooper leak detection systems enumerated in Reference 8 can be calibrated or tested during operation. ' C.9 The Cooper Technical Specif.icatiens include limiting conditions for identified and unidentified leakage.10 NPPD has identified the availability of the Cooper systems for detecting and monitoring leakage. Two of the three systems
- a. Sump flow measuring systems-
- b. Containment atmospheric radiation monitor, or ,
- c. Containment atmospheric sampling systems are always available.10 It cannot be determined from the above whether Cooper meets Regulatory Guide 1.45, Section C.
IV.B.I.a.(2) Leak Detection Requirements NUREG-0313, Rev. I requires that reactor shutdown be initiated when there is a 2-gpm increase in unidentified leakaga in 24 h. i For sump level monitoring systems with the fixed-measurement interval method, the level should be monitored every 4 h or less, a ) 28 i l
NPPD has not incorporated the provision for shutdown for a 2-gpm increase in unidentified leakage in 24 h into the Cooper Technical Specifications. Also, according to the Cooper Technical Specifications, the sump and air sampling leak detection systems are monitored at least once per day.7 IV.B.1.b.(3) Augmented ISI of Nonconforming "Nonservice Sensitive" ASME Code Class 2 Pipe NUREG-0313, Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an augmented ISI program. The augmented ISI program for ASME Code Class 1 piping differs from that required on Class 2 piping. Also, augmented ISI requirements differ for ASME Code Class 2 pipes to be inmected per Parts
, IV.3.1.b.(3) and IV.B.1.b.(4) of NUREG-0313, Rev. 1.
NPPD has submitted the augmented ISI program for nonconforming l
"nonservice sensitive" piping, but has not distinguished between the ASME Code Class 1 and Class 2 piping, and between the ASME Code Class 2 pipes which are to be inspected per Parts i
IV.B.l.b.(3) and IV.B.I.b.(4) of NUREG-0313, Rev. 1. Therefore, NPPD's program for ASME Code Class 2 piping cannot be evaluated. IV.B.l.b.(4) Augmented ISI for ASME Code Class 1 Pipe Welds with High Potential for Cracking NUREG-0313, Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an augmented ISI program. The augmented ISI program for ASME Code Class 1 piping differs from that required on Class 2 piping. Also, augmented ISI requirements differ for ASME Code Class 2 pipes to be inspected per Parts IV.B.l.b.(3) and IV.B.I.b.(4) of NUREG-0313, Rev. 1. 29
NPPD has submitted the augmented ISI program for nonconforming "nonservice sensitive" piping, but has not distinguished between the ASME Code Class 1 and Class 2 piping, and between the ASME ! Code Class 2 pipes which are to be inspected per Parts IV.8.1.b. (3) and IV.B. l.b.(4) of NUREG-0313, Rev.1. Therefore, NPPD's program for ASME Code Class 2 piping cannot be evaluated. IV.8.2.b. Augmented ISI of Nonconforming " Service Sensitive" Pipe NUREG-0313, Rev. I requires that ASME Code Class 1 " service sensitive" pipes be subject to an augmented ISI program. Selection methods for pipes to be examined and other technical details are found in Part IV.8.2.b. of NUREG-0313, Rev. 1. NPPD is examining nonconforming " service sensitive" piping per the guidelines set forth in General Electric's Service Information Letter (SIL) No.117, Rev.1, March 1976.8 Some details of SIL 117 are below. t Piping Systems Extent of Examination Recirculation Bypass 100% of welds Core Spray System 100% of welds RHR Shutdown Cooling 100% cf welds in one loop Recirculation System Select welds per ASME Section XI, 1974 Edition, Summer 1975 Addenda. Welds selected to be examined should be completed during the first 80-month period. For the balance of plant service lifetime, examination shall revert to the schedule in .
^
ASME Section XI. l 30 _ _ _ ~ _ _
Piping Systems Extent of Examination Inservice inspection of These examinations should be austenitic stainless conducted in accordance with the steel pipe runs within schedule specified in ASME Code, the reactor coolant Section XI, Subsection IWB, as boundary that operate required by the applicable flow with full coolant (RWCU) categories B-F and 8-J, with the during normal reactor exception that the required operation. examinations be completed during the first 80-month period. After the first 80-month period the examinations shall revert back to the ASME Section schedule. The extent of examination for the RHR shutdown cooling and recirculation system does not ineet NUREG-0313, Rev.1. IV.8.2.b.(6) Augmented ISI of Nonconforming " Service Sensitive" ASME Code 3 . Class 2 Pipe .- NUREG-0313, Rev. I requires that nonconforming ASME Code Class 1 and Class 2 piping be subjected to an auomented ISI program. The augmented ISI program for ASME Code Class 1 piping differs f(om that required on Class 2 piping.
;; PPD has not 1.dentified those nonconforming " service sensitive" pipes which are to be insoected per P&rt IV.B.2.b.(6) of NUREG-0313, Rev. 1. Data are ..eeded to determine which " service sensitive" ASME Code Class 2 pipes will be inspected and what inspection procedures I will be used.
1 31
l TABLE 4 ADDITIONAL DATA REQUIRED OF LICENSEE II.C Material Selection, Testing, and Processing Guidelines for BWRs with an Operating License Indicate what actions will be taken if any " service sensitive" piping is found to suffer any intergranular stress corrosion cracking (IGSCC). XV.B.1.a.(1) Leak Detection and Monitoring Systems
, 1. Indicate whether provisions have been made in the Cooper FSAR to monitor systems connected to the RCPB for signs of intersystem leakage (Subsection C.4 of Regulatory Guide 1.45).
- 2. Indicatewhethercalibrationoftheindicatorsaccountshar 4
the needed independent variables (Subsection C.7 of Regulatory Guide 1.45).
- 3. Indicate whether the Cooper leak detection and monitoring methods include airborne particulate radioactivity monitoring, condensate flow rate from air coolers monitoring, and airborne gaseous radicactivity monitoring (Subsection C.3 of Regulatory Guide 1.45).
- 4. Indicate whether the Cooper leakage detection and monitoring systems employed for unidentified leakage can detect a 1-gpm leak in I h (Subsection C.5 of Regulatory Guide 1.45).
IV.8.1.a.(2) Leak Detection Requirements None. 32 l
,. , _ . _ . , , . , . - .~w -. - -- --- - - "
'*~~ " -
IV.B.l.b.(3) Augmented ISI of Nonconforming "Nonservice Sensitive" ASME Code Class 2 Pipe Identify which ASME Code Class 2 pipe will be inspected per Part IV.B.I.b.(3) and which inspection procedures will be used. IV.B.l.b.(3) Augmented ISI for ASME Code Class 1 Pipe Welds Having a Design Cumulative Fatigue Usage Factor of 0.4 or More Identify which A3ME Code Class 2 pipe will be inspected per Part IV.B.1.b.(3) and which inspection procedures will be used. IV.B.I.b.(4) Augmented ISI of Nonconforming "Nonservice Sensitive" ASME Code Class 2 Pipe
~
IdentifywhichASMECode11 ass 2pipewillbeinspectedper Part IV.B.I.b.(4) and which inspection procedures will be used. IV.B.2.b. Augmented ISI of Nonconfonning " Service Sensitive" Pipe t None. IV.B.2.b.(6) Augmented ISI of Nonconforming " Service Sensitive" ASME Code Class 2 Pipe
- 1. Identify which ASME Code Class 2 pipe will be inspected per Part IV.B.2.b.(6).
- 2. Identify the inspection procedures for " service sensitive"
'. ASME Code Class 2 pipe. i
)
1 33 l _ , - - - - - - - , ----,--.-w-,.,+m,,--- ---, -p , -- - . w - ,
- 4. REFERENCES
- 1. E. D. Eason et al., The Cost Effectiveness of Countermeasures to Intergranular Stress Corrosion Cracking in BWR Piping, EPRI NP-1703, February 1981, p. A-04.
- 2. U.S. Nuclear Regulatory Commission Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping, U5NRG Report NUREG-0313, July 19//.
- 3. U.S. Nuclear Regulatory Commission, Technical Report, Investigation and Evaluation of Cracking in Austenitic Stainless Steel Piping of Boiling Water Reactor Plants, USNRC Report NUREG-75/067, October 1975.
- 4. U.S. Nuclear Regulatory Commission, Investigation and Evaluation of Stress-Corrosion Cracking in Piping of Light Water Reactor Plants, USNRC Report NUREG-0531, February 1979.
- 5. U.S. Nuclear Regulatory Commission, Technical Report on Material !
Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping, USNRC Report NUREG-OJ13, Rev. I, Ju ly 1960.
- 6. D. G. Eisenhut letter to all BWR licensees (except Humboldt Bay and La Crosse), " Implementation of NUREG-0313, Rev.1, Technical Report on Material Selection and Processing Guidelines for BWR Coolant Preesure Boundary Piping (Generic Task A-42)," Generic Letter 81-04, Febraary 26, 1981, 7 J. M. Pilant to D. G. Eisenhut letter, July 1, 1981 (NRC Accessioni No.: None given).
- 8. J. M. Pilant to D. B. Vassallo letter, December 2, 1982 (NRC Accession No.
- Nonegiven).
l
- 9. Cooper Nuclear Station Final Safety Analysis Report, Section 10.
- 10. Cooper Nuclear Station Technical Specifications.
I 34
I
, 'U.S. NUCLEA2 REGULATORY COMMISSION BIBLIOGRAPHIC D ATA SHEET EGG-FM-6251 4 TITLE AND SUBTITLE
- 2. (Leme b/mk/
Technical Evaluation of Integrity of the Cooper Nuclear Station Reactor Coolant Boundary Piping System s. RECIPIENT S ACCESSION NO.
- 7. AUTHOR (S)
- 5. DATE REPORT COMPLETED Peter K. Nagata * "'" ' ^"
July 1983 9 PERFORMING ORGANIZATION NAME AND MAILING ADORESS (include lip Coairl DATE REPORT ISSUED wo~ra Iveaa EG&G Idaho, Inc. gy 1%3
- s. ft,, ,,,,
Idaho Falls, ID 83415
- 8. (Leave omkl
- 12. SPONSORING ORGANIZATION NAME AND MAILING ADDRESS //nclude ten Codel Division of Licensing 10. PROJECT / TASK / WORK UNIT NO.
Office of_ Nuclear Reactor Regulation 11 FIN NO. U.S. Nuclear Regulatory Commission Washington, DC 20555 A6429
- 13. TYPE OF REPORT PE RIOD COVE RED (inctusive daars)
' 's
- 15. SUPPLEMENTARY NOTES
- 14. (Lesve avmel
- 16. ASSTR ACT 1200 words or lessi I
s 17 KEY WOROS AND DOCUMENT ANALYSIS 17a OtiSCRIPTORS 19 7b 'JENTIFIERSiOPEN ENDE O TERMS 18 AV AILABILITY STATEMENT 19. SECURITY CLASS ITnes recorr) 'l NO OF PAGES Unclassified Unlimited 2 vC c2 PRICE QQ'33 9yfgra,s,,,, , l ue PoRu sas m ei, _ _ _ _ _ _ . _ . _ . , _ _ . _ - . _ _ . . - _ . _ _ . , _ _ _ . . _ _ . _ , . _ _ _ _ _ _ .}}