Text

Inservice Inspection Plan Relief Requests
	ML040760747
Person / Time
Site:	McGuire, Mcguire
Issue date:	03/08/2004
From:	Gordon Peterson; Duke Energy Corp
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	Download: ML040760747 (36)
	v • d • e

_Duke

wPowere A Duke Energy Company GARY R. PETERSON Vice President McGuire Nuclear Station Duke Power MGO1VP / 12700 Hagers Ferry Road Huntersville, NC 28078-9340 704 875 5333 704 875 4809 fax grpeters@duke-energy.com March 8, 2004 U. S. Nuclear Regulatory Commission Document Control Desk Washington, D.C.

20555-0001

Subject:

Reference:

McGuire Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 Inservice Inspection Plan Relief Requests (1) Letter from Mr. G. R. Peterson of Duke Energy (Duke) to the NRC, dated December 18, 2003, and (2) Letter from Mr. G. R. Peterson of Duke to the NRC, dated January 5, 2004 As discussed in the referenced letters, the ISI program for McGuire Units 1 and 2 was revised in accordance with 10CFR50.55a(g)(4)(ii).

The ISI program for both Units 1 and 2 was revised to comply with the 1998 Edition through the 2000 Addenda of the ASME Boiler and Pressure Vessel Code Section XI.

The referenced letters also referred to a number of relief requests which are enclosed with this submittal.

Specific details are described in the enclosed relief requests.

/

Pursuant to the requirements of 10CFR50.55a(a)(3)(i), Duke requests NRC review and approval of the following relief requests: (1) Relief Request 02-003, "Request to use corrected ASME Code requirement for Clads 3 pressure tests,"

(2) Relief Request 03-002, "Request for alternative to IWF-5000 OM-1987, Part 4, snubber examinations," (3) Relief Request 03-003, "Request to use Code Case N-566-2 for Unit 2," and (4) Relief Request 03-005, "Request for alternative on pressurizer support skirt weld."

Pursuant to the requirements of 10CFR5d.55a(g)(4)(iv), Duke requests the use of a later code edition as the code of reference for the Relief Requests previously submitted as an alternative to the ASME Boiler and Pregsure Vessel Code, AS'S-/

www. duke-energy. corn

U.S. Nuclear Regulatory Commission March 8, 2004 Page 2 Section XI, 1995 Edition through the 1996 Addenda for McGuire Unit 1 (third ten-year interval).

Please direct any questions regarding this request to Norman T. Simms of Regulatory Compliance at (704) 875-4685.

G.R. Peterson Enclosures

U.S. Nuclear Regulatory Commission March 8, 2004 Page 3 xc w/enclosure:

Mr. L.A. Reyes US Nuclear Regulatory Commission, Region II Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303 Mr. R.E. Martin, Project Manager (addressee only)

Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission One White Flint North, Mail Stop O-8G9 11555 Rockville Pike Rockville, MD 20852 J.B. Brady Senior NRC Resident Inspector McGuire Nuclear Station

ENCLOSURE 1 RELIEF REQUEST NO.02-003 I

Duke Energy Corporation McGuire Nuclear Station - Unit 2 Third 10-Year Interval Relief Request Serial No.02-003 Pursuant to 10 CFR 50.55a (a) (3) (i), Duke Energy Corporation requests the use of an alternative to the ASME Boiler and Pressure Vessel Code,Section XI, 1998 Edition through the 2000 Addenda.

Specifically, Duke Energy Corporation requests approval to use, as an alternate, a system leakage test in lieu of a system hydrostatic test. A Code change removing the hydrostatic test requirement was incorporated in the 1993 Addenda for Class 1 and Class 2 pressure-retaining components, but was not incorporated for Class 3 components.

I.

Systems/Components for Which Alternative is Requested:

All McGuire Unit 2, Class 3, Category D-B, pressure-retaining components subject to IWD-5222 hydrostatic testing.

II.

Code Requirement:

Section XI, Table IWD-2500-1, of the ASME Code, 1998 Edition through the 2000 Addenda, requires a system leakage test each inspection period for Class 3 pressure-retaining components.

Additionally, Table IWD-2500-1 requires a system hydrostatic test each inspection interval for these same Class 3 pressure-retaining components.

III.

Code Requirement from Which Alternative is Requested:

Relief is requested from the mandatory requirement to perform a Class 3 hydrostatic pressure test (1WD-5222).

IV.

Basis for Requesting Alternative:

Consistent with the philosophy of ASME Code Case N-498-1, this request is based on performing the VT-2 visual examinations at nominal operating pressure in lieu of the interval hydrostatic pressure tests. A review of all Class 3 interval hydrostatic pressure tests performed at McGuire Nuclear Station to date has shown that a leak has never occurred in the base metal or in an existing weld. All leaks that have occurred have been in mechanical joints such as packing glands and body-to-bonnet connections.

Additionally, the ASME Boiler & Pressure Vessel Code,Section XI Committee has determined that a hydrostatic test only increases the leakage rate from that of a leakage test run at nominal operating pressure. That is, raising the test pressure from operating pressure to hydrostatic pressure has not identified any new leakage. Therefore, performing a VT-2 visual examination at nominal operating pressure provides reasonable' assurance of system integrity.

Duke Energy Corporation Page 2 of 3 Request For Alternative Serial No.02-003

Duke Energy Corporation McGuire Nuclear Station - Unit 2 Third 10-Year Interval Relief Request Serial No.02-003 V.

Alternate Examinations or Testing:

Duke Energy Corporation requests that a Class 3 system leakage test (IWD-5221) be conducted in lieu of the Class 3 system hydrostatic test (IWD-5222).

VI.

Justification for the Granting of Alternative:

The ASME Code Committee and the Nuclear Regulatory Commission have endorsed the use of a leakage test in lieu of a hydrostatic test for Class 1 and Class 2 pressure-retaining components in the 1998 Edition through the 2000 Addenda of the Boiler & Pressure Vessel Code,Section XI.

McGuire Nuclear Station requested and was granted relief from this requirement for their unit 1, third interval plan via Request for Relief serial number 01-002, revision 1 (TAC

MB2069). Therefore, the unit 2 system leakage test is sufficient to determine the leakage integrity of Class 3 pressure-retaining components at an acceptable level of quality and safety.

VII.

Implementation Schedule:

McGuire Unit 2 begins the third inspection interval on March 1, 2004. Duke Energy Corporation requests that approval be granted to permit use of this relief at that time.

Sponsored By:

Wm Date: 6/4/3 Approved By:

Date:

te:

Duke Energy Corporation Page 3 of 3 Request For Alternative Serial No.02-003

ENCLOSURE 2 RELIEF REQUEST NO.03-002

Serial No.03-002 Page I of 2 Duke Energy Corporation Station McGuire Unit 2 Third 10-Year Interval Request For Relief No.03-002 Pursuant to I0CFR50.55a(a)(3)(i), Duke Energy requests to use an alternative to the Section XI requirements of the ASME Boiler and Pressure Vessel Code. Accordingly, information is being submitted in support of our determination that the alternative provides an acceptable level of quality and safety.

Reference Code: ASME Boiler and Pressure Vessel Code,Section XI 1998 Edition through 2000 Addenda Notes: 1) This unit was previously granted relief to use the alternative during the second interval per Duke Request number 97-005 (letter to NRC dated 12/17/97), SER approval letter dated 5/27/98, and TAC numbers MA0623 & MA0624.

2) This unit third interval is scheduled to begin on 3/01/04.

3) The other unit, McGuire I was granted relief to use the alternative for its third interval per Duke Request number 01-004 (letter to NRC dated 6/01/01), SER approval letter dated 1/30/02, and TAC number MB2174.

I.

System / Components(s) for Which Relief is requested:

All Unit 2 safety-related ASME Section XI Code Class 1, 2, and 3 snubbers.

II.

Code Requirement from which Relief is requested:

Relief is requested from the requirements of Article IWF-5000, Subarticle IWF-5300.

An alternative will be provided from the following requirements.

(a) Inservice examinations shall be performed in accordance with ASME/ANSI OM, Part 4, using the VT-3 visual examination method described in IWA-2213.

(b) Inservice tests shall be performed in accordance with ASME/ANSI OM, Part 4.

(c) Integral and nonintegral attachments for snubbers, including lugs, bolting, pins, and clamps, shall be examined in accordance with the requirements of this Subsection.

III.

Basis for Relief:

ASME Section XI, 1998 Edition through 2000 Addenda, Subarticle IWF-5300 (a) and (b) specifies that snubber examinations and tests be performed in accordance with the first addenda to ASME/ANSI OM, Part 4 (published in 1998). Subarticle IWF-5300 (c) requires examinations per the IWF Subarticle.

Snubber examinations and tests are currently performed under the Updated Final Safety Analysis, Chapter 16, Selected Licensee Commitment (SLC) 16.9.15 (see Attachment A).

The current inspection program as defined by this SLC provides for an acceptable level of quality and safety equal to or greater than that of the proposed OM Standard.

Serial No.03-002 Page 2 of 2 The OM Standard provides for Failure Mode Grouping of snubbers which fail visual examination, meaning only those snubbers identified as being in that group would require shortened inspection intervals. Under the SLC program all snubbers in the population would be placed in a shortened inspection interval. On this basis the existing program is more conservative in corrective action than the OM Standard requirements.

The functional test plan required by the OM Standard also includes Failure Mode Groups. The use of failure mode grouping is required even for a single failure, and in some cases allows for the failed snubber to be reclassified as acceptable with no further testing. This is nonconservative for the large snubber population which exists at McGuire (over 300 snubbers per unit) as compared to the existing SLC program. The current program at McGuire requires supplemental testing for all failures until the desired confidence level is assured, with no allowances to reclassify failed snubbers.

IV.

Alternate Examination or Testing:

In lieu of implementing the requirements of Subarticle IWF-5300 (a), (b) and (c); it is proposed that the inservice examination and testing be performed under SLC 16.9.15.

V.

Justification for the Granting of Relief:

The SLC lists visual examination requirements for snubbers that are compatible with Section XI VT-3 requirements. The SLC also incorporates the reduced visual examination frequency table as provided in NRC Generic Letter 90-09. SLC use results in a significant reduction in unnecessary radiological exposure to plant personnel, a savings in company resources, and compliance with visual examination requirements while maintaining the same confidence level in snubber operability as that provided by following Section XI requirements.

Should this request be granted, the SLC 16.9.15 basis will be revised to reference the NRC approval of this relief request and identify that any revision to the snubber visual inspection and functional test requirements of the SLC shall consider the basis for the granted alternative from the ASME Code requirements and any resulting requirement for NRC review and approval.

VI.

Implementation Schedule:

Snubber visual examination and testing will be scheduled and performed in accordance with SLC 16.9.15 during the third inspection interval.

Prepared By:

A Date 2-5/c3 Approved By:

+

Date A

Attachment A - SLC 16.9.15

Snubbers 16.9.15 ATTACHMENT A 16.9 AUXILIARY SYSTEMS 16.9.15 Snubbers COMMITMENT All snubbers shall be OPERABLE.

NOTE--------------------------------------

Snubbers installed on non-safety systems may be excluded from these requirements provided their failure or the failure of the system on which they are installed would not have an adverse affect on any safety-related system.

APPLICABILITY MODES 1, 2, 3, and 4, MODES 5 and 6 for snubbers located on systems required OPERABLE in those MODES.

REMEDIAL ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A.

One or more snubbers A.1 Enter the applicable Immediately inoperable.

ACTIONS for any affected system(s) and component(s) that are determined to be inoperable.

B.

One or more snubbers B.1 Perform an engineering 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months failed to meet test evaluation.

acceptance criteria.

McGuire Units 1 and 2 1 6.9.1 5-1 Revision 25

Snubbers 16.9.15 TESTING REQUIREMENTS

NOTES----------------------------------------------------

1.

Each snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program.

2.

Snubbers which fail the visual inspection or the functional test acceptance criteria shall be repaired or replaced. Replacement snubbers and snubbers which have repairs which might affect the functional test results shall be tested to meet the functional test criteria before installation in the unit. Mechanical snubbers shall have met the acceptance criteria subsequent to their most recent service, and the freedom-of-motion test must have been performed within 12 months before being installed in the unit.

3.

As used herein, type of snubber shall mean snubbers of the same design and manufacturer, irrespective of capacity.

TEST FREQUENCY TR 16.9.15.1 -------------------------------- NOTES--------------------------------

1. Snubbers are categorized as inaccessible or accessible during reactor operation and may be inspected independently according to the schedule determined by Table 16.9.15-1.

2.

The first inspection interval using Table 16.9.15-1 shall be based upon the previous inspection interval as established by the requirements in effect before Technical Specification amendment 126.

Perform a visual inspection for each category of snubber.

In accordance with Table 16.9.15-1 TR 16.9.15.2 -------------------------------- NOTE---------------------------------

In case of a severe dynamic event, mechanical snubbers in that system which experienced the event shall be inspected during the refueling outage to assure that the mechanical snubbers have freedom of movement and are not frozen up Perform an inspection to determine if there has been a 18 months severe dynamic event for systems which have the potential for a severe dynamic event.

(continued)

McGuire Units 1 and 2 16.9.15-2 Revision 25

Snubbers 16.9.15 TESTING REQUIREMENTS (continued)

TEST FREQUENCY TR 16.9.15.3

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1. The large bore steam generator hydraulic snubbers shall be treated as a separate population for functional test purposes and are functional tested under Sample Plan 1.

2. If testing continues under Sample Plan 2 to between 100-200 snubbers(or 1-2 weeks) and the accept region has not been reached, then the actual % of population quality (C/N) should be used to prepare for extended or 100% testing.

Perform snubber functional testing on a representative sample of each type of snubber in accordance with one of the following three Sampling Plans:

1. Functionally test 10% of a type of snubber with an additional 10% tested for each functional testing failure, or

2. Functionally test a sample size and determine sample acceptance or continue testing using Figure 16.9.15-1, or

3. Functionally test a representative sample size and determine sample acceptance or rejection using the stated equation.

18 months TR 16.9.15.4--------------------------------NOTE---------------------------------

The parts replacement shall be documented and the documentation shall be retained for the duration of the unit operating license.

Verify that the service life of hydraulic snubbers has not 18 months been exceeded or will not be exceeded prior to the next scheduled surveillance inspection.

McGuire Units 1 and 2 16.9.15-3 Revision 25

I Snubbers 16.9.15 BASES All snubbers are required OPERABLE to ensure that the structural integrity of the Reactor Coolant System and all other safety-related systems is maintained during and following a seismic or other event initiating dynamic loads. Snubbers excluded from this inspection program are those installed on nonsafety-related systems and then only if their failure or failure of the system on which they are installed, would have no adverse effect on any safety-related system. Snubbers are classified and grouped by design and manufacturer but not by size. For example, mechanical snubbers utilizing the same design features of the 2 kip, 10 kip, and 100 kip capacity manufactured by Company "A" are of the same type. The same design mechanical snubbers manufactured by Company "B" for the purposes of this specification would be of a different type, as would hydraulic snubbers from either manufacturer.

The snubber requirements of SLC 16.9.15 were originally located in the Technical Specifications. The Nuclear Regulatory Commission (NRC) authorized the use of these requirements, while located in Technical Specifications, as an acceptable alternative to the requirements of the ASME Code, 1989 Edition, Section Xi, Article IWF-5000 (References 3, 4). Any revision to these snubber visual inspection and functional test requirements shall consider the basis for the granted relief from the ASME Code requirements and any resulting requirement for NRC review and approval.

Remedial Actions - A.1 Should one or more snubbers be inoperable, OPERABILITY of the affected system(s) and component(s) must be determined and the applicable ACTIONS entered immediately. If there remains a reasonable assurance of OPERABILITY of the affected system(s) or component(s) with the condition of an inoperable snubber(s), then it is not necessary to enter the respective ACTIONS for inoperable system(s) and component(s). A snubber removed from service for any reason cannot be considered OPERABLE since it is not connected to the supported system or component.

Remedial Actions - B.1 Should one or more snubbers fail to meet testing acceptance criteria or be discovered in a condition where failure is apparent, an engineering evaluation is to be performed within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , as described in "Functional Test Failure Analysis".

The snubber-testing program may remove snubbers from service and restore OPERABILITY of the snubber application by replacement with another like snubber. In this situation, if the removed snubber later fails to meet test acceptance criteria, Condition A is not applicable since the snubber component has no current required function; however, ACTION B.1 would be applicable. During the allowed 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months to perform an engineering evaluation or at any other time, when conditions of the affected system(s) and component(s) are determined to no longer support a reasonable assurance of OPERABILITY, applicable ACTIONS are to be entered immediately.

McGuire Units 1 and 2 16.9.15-4 Revision 25

Snubbers 16.9.15 BASES (continued)

Visual Inspections The visual inspection frequency is based upon maintaining a constant level of snubber protection to systems. Therefore, the required inspection interval varies inversely with the observed snubber failures and is determined by the number of inoperable snubbers found during an inspection. Inspections performed before that interval has elapsed may be used as a new reference point to determine the next inspection. However, the results of such early inspections performed before the original required time interval has elapsed (nominal time less 25%) may not be used to lengthen the required inspection interval. Any inspection whose results require a shorter inspection interval will override the previous schedule.

Visual inspections shall verify: (1) that there are no visible indications of damage or impaired OPERABILITY, and (2) attachments to the foundation or supporting structure are secure. Snubbers which appear inoperable as a result of visual inspections shall be classified as unacceptable and may be reclassified acceptable for the purpose of establishing the next visual inspection interval, provided that: (1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers irrespective of type that may be generically susceptible; and (2) the affected snubber is functionally tested in the as found condition and determined OPERABLE. A hydraulic snubber found with the fluid port uncovered and all hydraulic snubbers found connected to an inoperable common reservoir shall be classified as unacceptable and may be reclassified acceptable by functionally testing each snubber starting with the piston in the as-found setting, extending the piston rod in the tension direction.

Refueling Outage Inspections At each refueling, the systems which have the potential for a severe dynamic event, specifically, the main steam system (upstream of the main steam isolation valves) the main steam safety and power-operated relief valves and piping, auxiliary feedwater system, main steam supply to the auxiliary feedwater pump turbine, and the letdown and charging portion of the NV system shall be inspected to determine if there has been a severe dynamic event.

In case of a severe dynamic event, mechanical snubbers in that system which experienced the event shall be inspected during the refueling outage to assure that the mechanical snubbers have freedom of movement and are not frozen up. The inspection shall consist of verifying freedom of motion using one of the following: (1) manually induced snubber movement; (2) evaluation of in-place snubber piston setting; (3) stroking the mechanical snubber through its full range of travel. If one or more mechanical snubbers are found to be frozen up during this inspection, those snubbers shall be replaced or repaired before returning to power. The requirements of TR 16.9.15.1 are independent of the requirements of this item.

McGuire Units 1 and 2 16.9.15-5 Revision 25

Snubbers 16.9.15 BASES (continued)

Functional Testing During the first refueling shutdown and at least once per refueling thereafter, a representative sample of snubbers shall be tested using one of the following sample plans.

The large bore steam generator hydraulic snubbers shall be treated as a separate population for functional test purposes and are functional tested under Sample Plan 1. A 10% random sample from previously untested snubbers shall be tested at least once per refueling outage until the entire population has been tested. This testing cycle shall then begin anew. For each large bore steam generator hydraulic snubber that does not meet the functional test acceptance criteria, at least 10% of the remaining population of untested snubbers for that testing cycle shall be tested. The sample plan shall be selected prior to the test period and cannot be changed during the test period. The NRC shall be notified of the sample plan selected prior to the test period.

1. At least 10% of the required snubbers shall be functionally tested either in place or in a bench test. For each snubber that does not meet the functional test acceptance criteria, an additional 10% of the snubbers shall be functionally tested until no more failures are found or until all snubbers have been functionally tested; or

2. A representative sample of the required snubbers required shall be functionally tested in accordance with Figurel6.9.15-1. WC" is the total number of snubbers found not meeting the acceptance requirements (failures). The cumulative number of snubbers tested is denoted by 'N.'

Test results shall be plotted sequentially in the order of sample assignment (i.e., each snubber shall be plotted by its order in the random sample assignments, not by the order of testing). If at any time the point plotted falls in the "Accept region, testing of snubbers may be terminated. When the point plotted lies in the "Continue Testing" region, additional snubbers shall be tested until the point falls in the 'Accept" region, or all the required snubbers have been tested. Testing equipment failure during functional testing may invalidate that day's testing and allow that day's testing to resume anew at a later time, providing all snubbers tested with the failed equipment during the day of equipment failure are retested; or

3. An initial representative sample of fifty-five (55) snubbers shall be functionally tested.

For each snubber which does not meet the functional test acceptance criteria, another sample of at least one-half the size of the initial sample shall be tested until the total number tested is equal to the initial sample size multiplied by the factor, 1 + C/2, where NC" is the number of snubbers found which do not meet the functional test acceptance criteria. This can be plotted using an "Accept" line which follows the equation N = 55(1

+ C/2). Each snubber should be plotted as soon as it is tested. If the point plotted falls on or below the NAccept" line, testing may be discontinued, If the point plotted falls above the "Accept m line, testing must continue unless all snubbers have been tested.

The representative samples for the functional test sample plans shall be randomly selected from the required snubbers and reviewed before beginning the testing. The review shall ensure as far as practical that they are representative of the various configurations, operating environments, range of sizes, and capacities. Snubbers placed in the same McGuire Units I and 2 16.9.15-6 Revision 25

Snubbers 16.9.15 BASES (continued) locations as snubbers which failed the previous functional test shall be retested at the time of the next functional test but shall not be included in the sample plan. If during the functional testing, additional sampling is required due to failure of only one type of snubber, the functional testing results shall be reviewed at that time to determine if additional samples should be limited to the type of snubber which has failed the functional testing.

Figure 16.9.15-1 was developed using "Wald's Sequential Probability Ratio Plan" as described in "Quality Control and Industrial Statistics" by Acheson J. Duncan.

Permanent or other exemptions from the surveillance program for individual snubbers may be granted by the NRC if a justifiable basis for exemption is presented and, if applicable, snubber life destructive testing was performed to qualify the snubber for the applicable design conditions at either the completion of their fabrication or at a subsequent date.

Functional Test Acceptance Criteria The snubber functional test shall verify that:

1. Activation (restraining action) is achieved within the specified range in both tension and compression, except that inertia dependent, acceleration limiting mechanical snubbers may be tested to verify only that activation takes place in both directions of travel;

2. Snubber bleed, or release rate where required, is present in both tension and compression, within the specified range;

3. Where required, the force required to initiate or maintain motion of the snubber is within the specified range in both directions of travel; and

4. For snubbers specifically required not to displace under continuous load, the ability of the snubber to withstand load without displacement.

Testing methods may be used to measure parameters indirectly or parameters other than those specified if those results can be correlated to the specified parameters through established methods.

Functional Test Failure Analysis An engineering evaluation shall be made of each failure to meet the functional test acceptance criteria to determine the cause of the failure. The results of this evaluation shall be used, if applicable, in selecting snubbers to be tested in an effort to determine the OPERABILITY of other snubbers irrespective of type which may be subject to the same failure mode.

For the snubbers found inoperable, an engineering evaluation shall be performed on the components to which the inoperable snubbers are attached. The purpose of this engineering evaluation shall be to determine if the components to which the inoperable McGuire Units 1 and 2 16.9.15-7 Revision 25

Snubbers 16.9.15 BASES (continued) snubbers are attached were adversely affected by the inoperability of the snubbers in order to ensure that the component remains capable of meeting the designed service.

If any snubber selected for functional testing either fails to activate or fails to move, i.e.,

frozen-in-place, the cause will be evaluated and, if caused by manufacturer or design deficiency, all snubbers of the same type subject to the same defect shall be evaluated in a manner to ensure their OPERABILITY. This testing requirement shall be independent of the requirements stated in TR 16.9.15.3 for snubbers not meeting the functional acceptance criteria.

Service Life The expected service life for the various seals, seal materials, and applications shall be determined and established based on engineering information and the seals shall be replaced so that the expected service life will not be exceeded during a period when the snubber is required to be OPERABLE.

The service life of a snubber is established via manufacturer input and information through consideration of the snubber service conditions and associated installation and maintenance records (newly installed snubber, seal replaced, spring replaced, in high radiation area, in high temperature area, etc.). The requirement to monitor the snubber service life is included to ensure that the snubbers periodically undergo a performance evaluation in view of their age and operating conditions. These records will provide statistical bases for future consideration of snubber service life. The requirements for the maintenance of records and the snubber service life review are not intended to affect plant operation.

REFERENCES

1. Letter from M. S. Tuckman to NRC, Licensing Position Regarding Snubbers, May 20, 1999.

2. Letter from NRC to H.B. Barron, Licensing Position Regarding Snubbers, July 9, 1999.

3. Letter from H.B. Barron to NRC, Request for Relief 97-005, Snubber Inspections -

Performance and Schedule, December 17, 1997.

4. Letter from NRC to H.B. Barron, Relief Request for Snubber Visual examination and Functional Testing, May 27, 1998.

5. Letter from H.B. Barron to NRC, Request for Relief 01-004, June 1, 2001.

6. Letter from NRC to M.S Tuckman, Safety Evaluation of Relief Request No.01-004, Alternative for Snubber Examinations, January 30, 2002.

McGuire Units 1 and 2 16.9.15-8 Revision 25

Snubbers 16.9.15 TABLE 16.9.15-1 SNUBBER VISUAL INSPECTION INTERVAL NUMBER OF UNACCEPTABLE SNUBBERS Population or Category Column A Column A Column C (Notes 1, 2)

Extended Interval Repeat Interval Reduced Interval (Notes 3, 6)

(Notes 4, 6)

(Notes 5, 6) 1 0

0 1

80 0

0 2

100 0

1 4

150 0

3 8

200 2

5 13 300 5

12 25 400 8

18 36 500 12 24 48 750 20 40 78

>1000 29 56 109 NOTES:

1. The next visual inspection interval for a snubber population or category size shall be determined based upon the previous inspection interval and the number of unacceptable snubbers found during that interval. Snubbers may be categorized, based upon their accessibility during power operation, as accessible or inaccessible. The categories may be examined separately or jointly.

However, the licensee must make and document that decision before any inspection and shall use that decision as the basis upon which to determine the next inspection interval for that category.

2. Interpolation between population or category size and the number of unacceptable snubbers is permissible. Use next lower integer for the value of the limit for Columns A, B, or C if that integer includes a fractional value of unacceptable snubbers as described by interpolation.

3.

If the number of unacceptable snubbers is equal to or less than the number in Column A, the next inspection interval may be twice the previous interval but not greater than 48 months.

4.

If the number of unacceptable snubbers is equal to or less than the number in Column B but greater than the number in Column A, the next inspection shall be the same as the previous interval.

5. If the number of unacceptable snubbers is equal to or greater than the number in Column C, the next inspection interval shall be two-thirds of the previous interval. However, if the number of unacceptable snubbers is less than the number in Column C but greater than the number in Column B, the next interval shall be reduced proportionally by interpolation, that is, the previous interval shall be reduced by a factor that is one third of the ratio of the difference between the number of unacceptable snubbers found during the previous interval and the number in Column B to the difference in the numbers in Columns B and C.

6. The provisions of SLC 16.2.7 are applicable for all inspection intervals up to and including 48 months.

McGuire Units 1 and 2 16.9.15-9 Revision 25

Snubbers 16.9.15 10 9

8 7

C 6

5 4

3 2

1 CONTINUE TESTING C = 0.055N-2.007

/_

ACCEPT 10 20 30 40 50 60 70 80 90 100 N

c FIGURE 16.9.15-1 SAMPLE PLAN 2 FOR SNUBBER FUNCTIONAL TEST McGuire Units 1 and 2 16.9.15-10 Revision 25

ENCLOSURE 3 RELIEF REQUEST NO.03-003

Serial No.03-003 Page 1 of 5 Attachment DUKE ENERGY CORPORATION Request for Alternative ASME Boiler and Pressure Vessel Code,Section XI

Background:

Pursuant to 10 CFR 50.55a (a) (3) (i), Duke Energy Corporation requests the use of an alternative to the 1998 Edition with the 2000 Addenda of Section XI of the ASME Boiler and Pressure Vessel Code (Code) for the third inspection interval at McGuire Unit 2.

Duke Energy Corporation requested relief via Request for Relief serial number 97-GO-001, revision 2, and was granted NRC approval via Safety Evaluation Report, Docket No 50-370, dated March 23, 2000, to use an evaluation of the mechanical joint as an alternative to pulling the bolt in the second inspection interval.

Since the submittal of that Request for Relief, ASME has published a Code Case that is essentially the same alternative.

This Code Case is N-566-2.

I.

Systems/Components for Which Alternative is Requested:

All Class 1, 2, and 3 systems/components subject to IWA-5000 pressure testing.

II.

Code Requirement:

Section XI of the ASME Code, 1998 Edition with 2000 Addenda, Subsection IWA-5250(a)(2) states, "If leakage occurs at a bolted connection in a system borated for the purpose of controlling reactivity, one of the bolts shall be removed, VT-3 examined, and evaluated in accordance with IWA-3100.

The bolt selected shall be the one closest to the source of the leakage.

When the removed bolt has evidence of degradation, all remaining bolting in the connection shall be removed, VT-3 examined, and evaluated in accordance with IWA-3100."

Serial No.03-003 Page 2 of 5 III. Requirement for Which Alternative Is Requested:

Relief is requested from the requirement to remove the bolt closest to the source of leakage when leakage is detected at a mechanical connection.

IV.

Basis for Requesting Alternative:

Removal of pressure retaining bolting at mechanical connections for visual, VT-3 examination and subsequent evaluation in locations where leakage has been identified is not always the most discerning course of action to determine the acceptability of the bolting.

The Code requirement to remove, examine, and evaluate bolting in this situation does not allow the owner to consider other factors which may indicate the acceptability of mechanical joint bolting.

Other factors that should be considered when evaluating bolting acceptability when leakage has been identified at a mechanical joint include, but are not limited to:

joint bolting material, service age of joint bolting materials, location of the leakage, history of leakage at the joint, evidence of corrosion with the joint assembled, and corrosiveness of process fluid.

Performance of the pressure test while the system is in service may identify leakage at a bolted connection that, upon evaluation, may conclude the integrity and pressure retaining ability of the joint is not challenged. It would not be prudent to impact the availability of a safety system by removing the system from service to address a leak that does not challenge the system's ability to perform its safety function.

A situation frequently encountered at Duke Energy Corporation is the complete replacement of bolting materials (studs, bolts, nuts, washers, etc.) at mechanical joints during plant outages. When the associated system piping is pressurized during plant start up, leakage may be identified at these joints.

The root cause of this leakage is most often due to thermal expansion of the piping and bolting materials and subsequent fluid seepage at the joint gasket. Proper retorquing of the bolting, in most cases, stops the leakage. Removal of the bolting to evaluate for corrosion would be unwarranted in this situation due to the new condition of the bolting materials.

Serial No.03-003 Page 3 of 5 V.

Alternative Examinations:

When leakage is identified at bolted connections by Visual, VT-2 examination during system pressure testing, an evaluation will be performed to determine the susceptibility of the bolting to corrosion and to assess the potential for failure as stated in Code Case N-566-2.

The evaluation will consider the following factors:

1. the number and service age of the bolts; 2.bolt and component material;

3. corrosiveness of process fluid;

4. leakage location and system function; 5.leakage history at connection or other system components; 6.visual evidence of corrosion at the assembled connection.

When the evaluation of the above variables is concluded and the evaluation determines that the leaking condition has not degraded the fasteners, then no further action is necessary.

However, reasonable attempts to stop the leakage shall be taken.

If the evaluations of the variables above indicate the need for further evaluation, or no evaluation is performed, then a bolt closest to the source of leakage shall be removed and VT-31 visually examined.

When the removed bolting shows evidence of rejectable degradation, all remaining bolts in the connection shall be removed and VT-3 visually examined.

If the leakage is identified when the bolted connection is in service or Technical Specifications require it to be operable, and the information in the evaluation is supportive, the removal of the bolt for VT-3 visual examination may be deferred to the next component/system outage of sufficient duration.

l The acceptance criteria for Visual, VT-1 will be used to assess the acceptability of the bolting.

Serial No.03-003 Page 4 of 5 VI.

Justification for Granting Alternative:

The purpose of the Code required corrective action to remove bolts and visually examine them for degradation as stated in IWA-5250(a)(2) is to ensure joint integrity.

Section V above provides alternative methods to ensure joint integrity of bolted connections. These alternative methods have been determined to provide an acceptable level of quality and safety.

VII. Implementation Schedule:

McGuire Unit 2 begins the third inspection interval on March 1, 2004.

Duke Energy Corporation requests that approval be granted to permit use of this relief at that time.

Oon&aWWX Sponsored By:

Approved By: WI)

%~eAA 14 Date: 71b103

Date:

e:

14i3

Serial No.03-003 Page 5 of 5 CASE N-566-2 CASES OF ASMIFE DO1L AND anUStMX VESSE CODE Apprwial Date: March 28. 2001 See Numeric Index lot expiration and any rteatfinaon dates.

Case No566-2 Corrective Action for Leakage Identified at Bolted ConnectionsSection XI, Division 1 InquIry: What alternative to the requirements of IWA-5250(a)(2) may be used when leakage is detected at bolted connections?

Reply: It is the opinion of the Committee that, as an alternative to the requirements of IWA-5250(aX2),

the requirements of (a) or (b) below shall be met.

(a) The kakage shall be stopped, and the bolting aMn component matcril3 shall be evaluated for joint integrity as described in (c) below.

(b) If the leakage is not stopped, the Owner shall evaluate the structural integrity and consequences of continuing operation, and the effect on the system operability of continued leakage. This engineering evalu-ation shall Include the considerations listed In (c) below.

(c) The evaluation of (a) and (b) above Is to determine the susceptibility of the bolting to corrosion and failure.

This evaluation shall include the following:

(I) the number and service age of the bolts:

(2) bolt and component material; (3) corrosiveness of process fluid; (4) leakage location and system function; (5) leakage history at the connection or other system components:

(6) visual evidence of corrosion at the assembled connection.

For Information Only

ENCLOSURE 4 RELIEF REQUEST NO.03-005

Serial No.03-005 Page 1 of 3 Duke Energy Corporation McGuire Nuclear Station Units 1 & 2 THIRD 10-YEAR INTERVAL REQUEST FOR ALTERNATIVE NO.03-005 Pursuant to 10CFR50.55a(a)(3)(i), Duke Energy requests approval to use an alternative to ASME Boiler and Pressure Vessel Code Section XI requirements. Accordingly, information is being submitted to support our determination that the alternative provides an acceptable level of quality and safety.

References:

ASME Section XI Code, 1998 Edition through the 2000 Addenda Third 10-Year Interval - Inservice Inspection Plans Unit 1 - The third interval began on 12-01-01 Unit 2 - The third interval is scheduled to begin on 3-01-04 Note:

These units were previously granted relief to use the same alternative during the second interval per Duke request number 00-001 transmitted to the NRC via letter dated 04/05/00. SER approval was granted via letter dated 08/23/01 (reference TAC numbers MB2325 & MB2326).

I.

System/Component for Which the Alternative is Requested:

Pressurizer - Welded Attachment Unit Item No.

Weld ID No.

Description 1

B110.010.001 lPZR-SKIRT Pressurizer Support Skirt to Lower Head Weld 2

B 10.010.001 2PZR-SKIRT Pressurizer Support Skirt to Lower Head Weld II.

Code Requirement:

ASME Section XI, 1998 Edition through the 2000 Addenda, Table IWB-2500-1, Examination Category B-K, Welded Attachments for Vessels, Piping, Pumps, and Valves, Item No. B 10.10, Pressure Vessels, Welded Attachments, Figure No.

IWB-2500-13, Surface Examination of Attachment Weld Length as modified by the latest final rule making on 10 CFR Part 50 that became effective on August 7, 2003. Paragraph 50.55a(b)(2)(xxi)(C) identifies a limitation on the code edition/addenda applicability for use of Table IWB-2500-1, Examination Category B-K, Item B 10.10. It specifically states: "... the 1995 Addenda must be applied when using the 1997 Addenda through the latest edition and addenda incorporated by reference in paragraph (b)(2) of this section."

Serial No.03-005 Page 2 of 3 III.

Code Requirement for Which the Alternative is Requested:

An alternative examination, by a combination of methods, is requested to satisfy the 10 CFR 50.55a limitation discussed in Section II above. Figure number IWB-2500-13 and associated notes describe the Pressurizer Support Skirt to Lower Head welded joint configuration and require a surface examination of surfaces A-B and C-D. Note 2 specifically states: "The extent of the examination includes essentially 100% of the length of the attachment weld at each attachment subject to examination."

IV.

Basis for Alternative Examination:

Duke Energy requests relief from the surface examination method required on surface C-D as shown on Attachment 1. Surface C-D is not accessible for examination for the following reasons:

1. The Pressurizer heater cables cause an interference and they must be disconnected to provide access. Previously this work caused termination joint and ceramic insulator damage that had to be repaired. (See Attachment 2)

2. The maximum clearance between the inside surface of the support skirt and the outside row of the heaters is 14 inches. This is insufficient clearance for performing the required surface examination. (See Attachment 3)

3. The inside of the support skirt is a high radiation area. Personnel performing the required examination could receive a significant dose. The general area dose rate is 400 mr/hr and the contact dose rates range from 1,000 to 3,000 mr/hr.

V.

Alternate Examination or Testing:

Duke proposes to use the ultrasonic method for examination of the inside circumference weld surface C-D. This inner weld surface will be scanned from the exterior of the skirt by a 300 shear wave from one axial direction covering 96% of the required examination volume; a 450 shear wave from the opposite axial direction covering 50% of the required examination volume; a 450 shear wave circumferential scan, clockwise and counter-clockwise, covering 76% of the required examination volume; and a straight beam longitudinal wave examination covering 76% of the examination volume. These scans represent the estimated maximum obtainable examination coverage with the ultrasonic method. Duke will also perform the Code specified surface examination method on the outside circumference weld surface A-B. (See Attachment 4)

Serial No.03-005 Page 3 of 3 VI.

Justification for Granting Relief:

The ultrasonic method has been shown to be capable of detecting surface connected flaws in pressure vessel welds when a properly designed technique is used. The ultrasonic procedure and the basic calibration block will conform to the requirements of ASME Section XI, Appendix 1, 1998 Edition through the 2000 Addenda.

VII.

Implementation Schedule:

These weld examinations will be scheduled in accordance with ASME Section XI requirements as shown in the McGuire Nuclear Station, Third 10-Year Interval, Inservice Inspection Plan for both Units 1 and 2.

VIII. Other Information:

The following individuals contributed to the development of this request for alternative. Gary Scarboro (ISI Plan Manager) sections I-VIII, Jim McArdle (NDE Level III) sections IV-VI, and Kevin Rhyne (Supervising Engineer) final review.

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