Limerick, Units 1 and 2 - Nuclear Regulatory CommissionU.S. Nuclear Regulatory Commission License Amendment Request Revise Snubber Surveillance Requirements March 29, 2016 Page 2 In

Exelon Generation®

March 29, 2016

U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Limerick Generating Station, Units 1 and 2

200 Exelon Way Kennett Square. PA 19348

www.exeloncorp com

10 CFR 50.90

Renewed Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject: Request for License Amendment to Revise Limerick Generating Station Snubber Surveillance Requirements

In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Exelon Generation Company, LLC (EGC) requests an amendment to the Technical Specifications (TS), Appendix A of Renewed Facility Operating License Nos. NPF-39 and NPF-85 for Limerick Generating Station (LGS), Units 1 and 2, respectively.

The proposed changes will revise LGS snubber surveillance requirements contained in TS. EGC has concluded that the proposed changes present no significant hazards consideration under the standards set forth in 10 CFR 50.92, "Issuance of Amendment."

The proposed changes have been reviewed by the LGS Plant Operations Review Committee and approved by the Nuclear Safety Review Board in accordance with the requirements of the EGC Quality Assurance Program.

Attachment 1 provides an evaluation of the proposed changes, including a detailed description, technical and regulatory evaluations, and an environmental consideration. Attachment 2 provides the existing TS pages marked up to show the proposed changes. The marked up TS Bases pages are provided for information only in Attachment 3. Attachment 4 contains a detailed comparison of the current TS 4. 7.4 Surveillance Requirements to the proposed ISi program requirements and justification for changes. Attachment 5 provides a copy of the proposed Snubber Program.

There are no regulatory commitments contained in this submittal.

EGC requests approval of the proposed license amendment by March 29, 2017, with the amendment being implemented within 60 days of issuance, to coincide with the fourth lnservice Inspection Interval which begins February 1, 2017.

U.S. Nuclear Regulatory Commission License Amendment Request Revise Snubber Surveillance Requirements March 29, 2016 Page 2

In accordance with 1 O CFR 50.91, "Notice for public comment; State consultation," paragraph (b), Exelon is notifying the Commonwealth of Pennsylvania of this application for license amendment by transmitting a copy of this letter and its attachments to the designated State Official.

Should you have any questions regarding this submittal, please contact Ms. Stephanie J. Hanson at (610) 765-5143.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 29th day of March 2016.

Respectfully,

David P. Helker Manager, Licensing and Regulatory Affairs Exelon Generation Company, LLC

Attachments: 1 . Evaluation of Proposed Changes 2. Markup of Technical Specifications Pages 3. Markup of Technical Specification Bases Pages (For Information Only) 4. TS 4.7.4 Surveillance Requirements Comparison to ASME OM Code

Subsection I STD 5. Proposed Snubber Program

cc: USNRC Region I, Regional Administrator USNRC Senior Resident Inspector, LGS USNRC Project Manager, LGS Director, Bureau of Radiation Protection - Pennsylvania Department

of Environmental Protection

ATTACHMENT 1

Evaluation of Proposed Changes

Limerick Generating Station

Renewed Facility Operating License Nos. NPF-39 and NPF-85

Docket Nos. 50-352 and 50-353

Subject: Request for License Amendment to Revise Limerick Generating Station Snubber Surveillance Requirements

1.0 SUMMARY DESCRIPTION

2.0 DETAILED DESCRIPTION

3.0 TECHNICAL EVALUATION

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria

4.2 Precedence

4.3 No Significant Hazards Consideration

4.4 Conclusions

5.0 ENVIRONMENTAL CONSIDERATION

6.0 REFERENCES

License Amendment Request Revise Snubber Surveillance Requirements Evaluation of Proposed Changes Docket Nos. 50-352 and 20-353

1.0 SUMMARY DESCRIPTION

Attachment 1 Page 1 of 5

In accordance with 1 O CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Exelon Generation Company, LLC (EGC) requests an amendment to the Technical Specifications (TS}, Appendix A of Renewed Facility Operating License Nos. NPF-39 and NPF-85 for Limerick Generating Station (LGS), Units 1 and 2. The proposed changes will revise the TS surveillance requirements for snubbers to conform to the revised LGS Snubber Program.

2.0 DETAILED DESCRIPTION

LGS will be starting the fourth 10-year lnservice Inspection (ISi) interval on February 1, 2017. The fourth 10-year interval will be using the American Society of Mechanical Engineers (ASME) Section XI Code, 2007 Edition with the 2008 Addenda. Currently, snubber inspection and testing are performed in accordance with the specific requirements of TS 4.7.4.

1 O CFR 50.55a(g)(4)(ii) requires that inservice examination of components conducted during successive 120-month inspection intervals must comply with the requirements of the latest edition and addenda of the Code incorporated by reference in 1 O CFR 50.55a(a) 12 months before the start of the 120-month inspection interval. If a revised inspection program for a facility conflicts with the TS for the facility, 1 O CFR 50.55a(g)(5)(ii) requires licensees to apply to the Commission for amendment of the TS to conform the TS to the revised program.

For LGS, the inspection and testing of snubbers is performed in accordance with plant TS. LGS intends to adopt Subsection ISTD, "Preservice and lnservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water Reactor Nuclear Power Plants," of the ASME OM Code, 2004 Edition through the 2006 Addenda, in place of the requirements for snubbers in the current plant TS.

The purpose of this license amendment request is to remove the specific surveillance requirements for demonstrating snubber operability from the TS since the inspection program has been revised to include the requirements of the OM Code Subsection ISTD in the Snubber Program. The proposed changes to TS 4.7.4 are necessary to conform the Technical Specifications to the revised inspection program for snubbers.

The proposed changes to the LGS TS are summarized below: 1. TS Section 4.7.4 is being revised to remove specific surveillance requirements for

demonstrating snubber operability. The current requirements will be replaced by a reference to the "Snubber Program."

2. The "Snubber Program," as described in new TS Section 6.8.4.k will provide a description of the snubber program requirements.

3. TS Section 4.7.4.d "Transient Event Inspection" will be removed and incorporated into the Technical Requirements Manual.

Attachment 2 provides the existing TS pages marked up to show the proposed changes. The marked up TS Bases pages are provided for information only in Attachment 3. A comparison of the current TS 4.7.4 requirements to the revised snubber program requirements and justification



of the changes are provided in Attachment 4. Attachment 5 contains a copy of the proposed Snubber Program.

3.0 TECHNICAL EVALUATION

Licensees are required by 1 O CFR 50.55a(g) or 1 O CFR 50.55a(b)(3)(v) to perform the inspection and testing of snubbers in accordance with ASME B&PV Code, Section XI or the OM Code and the applicable addenda, except where the NRG has granted specific written relief pursuant to 1 O CFR 50.55a(g)(6)(i), or authorized alternatives pursuant to 1 O CFR 50.55a(z). 1 O CFR 50.55a(b)(3)(v)(B) states that licensees shall comply with the provisions for examining and testing snubbers in Subsection ISTD of the ASME OM Code and make appropriate changes to their Technical Specifications or licensee-controlled documents when using the 2006 Addenda or later editions and addenda of Section XI of the ASME B&PV Code. LGS will be using the 2007 Edition with the 2008 Addenda of the Section XI ASME Code for the fourth ISi Interval.

The proposed changes replace the specific TS requirements for snubber examination, testing and service life monitoring with a reference to the Snubber Program, thereby ensuring the TS remain consistent with the Snubber Program.

Snubbers will continue to be demonstrated OPERABLE by performance of the Snubber Program. This program will be required to be maintained in compliance with 1 O CFR 50.55a per the proposed new TS Section. The program for inspection and testing of snubbers in accordance with ASME B&PV Code, Section XI or the OM Code and the applicable addenda as required by 1 O CFR 50.55a(g) is required to include evaluation of supported components/systems when snubbers are found to be unacceptable.

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria

1 O CFR 50.55a(g)(4)(ii) requires that inservice examination of components conducted during successive 120-month inspection intervals must comply with the requirements of the latest edition and addenda of the Code incorporated by reference in 1 O CFR 50.55a(a) 12 months before the start of the 120-month inspection interval.

1 O CFR 50.55a(b)(3)(v)(B) states that licensees shall comply with the provisions for examining and testing snubbers in Subsection ISTD of the ASME OM Code and make appropriate changes to their Technical Specifications or licensee-controlled documents when using the 2006 Addenda or later editions and addenda of Section XI of the ASME B&PV Code.

If a revised inspection program for a facility conflicts with the TS of the facility, 1 O CFR 50.55a(g)(5)(ii) requires licensees to apply to the Commission for amendment of the TS to conform the TS to the revised inspection program for snubbers.

The proposed changes amend the TS surveillance requirements to conform the TS to the revised inspection program for snubbers which shall meet the requirements of 1 O CFR



50.55a(g) except where the NRC has granted specific written relief, pursuant to 10 CFR 50.55a(g)(6)(i), or authorized alternatives pursuant to 10 CFR 50.55a(z).

4.2 Precedence

The proposed changes to TS 4.7.4 are similar to changes submitted by Public Service Enterprise Group (PSEG) Nuclear, LLC for Salem Generating Station, Units 1 and 2, Dominion Nuclear Connecticut (DNC), Inc for Millstone Power Station, and Exelon Generation Company, LLC (EGC) for Oyster Creek Nuclear Generating Station. The applicable references for these changes are provided below:

1. Letter from R. E. Ennis (U.S. Nuclear Regulatory Commission) to T. Joyce (PSEG Nuclear, LLC), "Salem Nuclear Generating Station, Unit Nos. 1 and 2 - Issuance of Amendments RE: Technical Specification Requirements for Snubbers (TAC Nos. ME4796 AND ME4797}," dated August 25, 2011.

2. Letter from J. Kim (U.S. Nuclear Regulatory Commission) to D. A. Heacock (Dominion Nuclear), "Millstone Power Station, Unit 2 - Issuance of Amendment RE: Snubber Surveillance Requirements (TAC No. ME7221)," dated June 28, 2012.

3. Letter from J. G. Lamb (U.S. Nuclear Regulatory Commission) to B. C. Hanson (Exelon Nuclear), "Oyster Creek Nuclear Generating Station - Issuance of Amendment to Revise Technical Specifications for Snubber Surveillance Requirements (TAC No. MF4124)," dated April 3, 2015.

4.3 No Significant Hazards Consideration

In accordance with 1 O CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Exelon Generation Company, LLC (EGC) requests an amendment to the Technical Specifications (TS), Appendix A of Renewed Facility Operating License Nos. NPF-39 and NPF-85 for Limerick Generating Station (LGS). The proposed changes would revise the TS surveillance requirements for snubbers to conform to the revised LGS inservice inspection (ISi program).

EGC has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 1 O CFR 50.92, "Issuance of amendment," as discussed below:

1. Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No

The proposed changes will revise TS 4.7.4 to conform the TS to the revised Snubber Program. Snubber examination, testing, and service life monitoring will continue to meet the requirements of 10 CFR 50.55a(g). Snubber examination, testing, and service life monitoring are not initiators of any accident previously evaluated. Therefore, the probability of an accident previously evaluated is not significantly increased.



Snubbers will continue to be demonstrated OPERABLE by performance of a program for examination, testing, and service life monitoring in compliance with 10 CFR 50.55a or authorized alternatives. The proposed changes do not adversely affect plant operations, design functions, or analyses that verify the capability of systems, structures, and components to perform their design functions. Therefore, the consequences of accidents previously evaluated are not significantly increased.

Based on the above, these proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed amendment create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No

The proposed changes do not involve any physical alteration of plant equipment. The proposed changes do not alter the method by which any safety-related system performs its function. As such, no new or different types of equipment will be installed, and the basic operation of installed equipment is unchanged. The methods governing plant operation and testing remain consistent with current safety analysis assumptions.

Therefore, it is concluded that these proposed changes do not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No

The proposed changes ensure snubber examination, testing, and service life monitoring will continue to meet the requirements of 1 O CFR 50.55a(g). Snubbers will continue to be demonstrated OPERABLE by performance of a program for examination, testing, and service life monitoring in compliance with 10 CFR 50.55a or authorized alternatives.

Therefore, it is concluded that the proposed changes do not involve a significant reduction in a margin of safety.

4.4 Conclusions

In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.


5.0 ENVIRONMENTAL CONSIDERATION


A review has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 1 O CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 1 O CFR 51.22(c)(9). Therefore, pursuant to 1 O CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

6.0 REFERENCES

1. 1 O CFR 50.55a, "Codes and standards."

2. American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) 2004 Edition through the 2006 Addenda.

3. American Society of Mechanical Engineers (ASME) Section XI, B&PV Code for Operation and Maintenance of Nuclear Power Plants 2007 Edition with the 2008 Addenda.

ATTACHMENT 2

Markup of Technical Specifications Pages




REVISED TECHNICAL SPECIFICATIONS PAGES

Unit 1 TS Pages 3/4 7-11

3/4 7-11a 3/4 7-11b 3/4 7-12 3/4 7-13 3/4 7-14 3/4 7-15 3/4 7-16

6-14d

Unit 2 TS Pages 3/4 7-11

3/4 7-11a 3/4 7-11b 3/4 7-12 3/4 7-13 3/4 7-14 3/4 7-15 3/4 7-16

6-14d

PLANT SYSTEMS 3/4.7.4 SNUBBERS LIMITING CONDITION FOR OPERATION 3.7.4 All snubbers shall be OPERABLE. APPLICABILITY: OPERATIONAL CONDITIONS 1, 2, and 3. OPERATIONAL CONDITIONS 4 and 5 for snubbers located on systems required OPERABLE in those OPERATIONAL CONDITIONS. ACTION: With one or more snubbers inoperable on any system, within 72 hours replace or restore the inoperable snubber(s) to OPERABLE status and perform an engineering evaluation per Specification 4.7.4g on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for that system. SURVEILLANCE REQUIREMENTS 4.7.4 Each snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the requirements of Specification 4.0.5. a. Inspection Types As used in this specification, type of snubber shall mean snubbers of the

same design and manufacturer, irrespective of capacity. b. Visual Inspections Snubbers are categorized as inaccessible or accessible during reactor

operation. Each of these categories (inaccessible and accessible) may be inspected independently according to the schedule determined by Table 4.7.4-1. The visual inspection interval for each type of snubber shall be determined based upon the criteria provided in Table 4.7.4-1 and the first inspection interval determined using this criteria shall be based upon the previous inspection interval as established by the requirements in effect before amendment no. 51.

LIMERICK - UNIT 1 3/4 7-11 Amendment No. 51

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Snubber Program.

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the Snubber Program.

TABLE 4.7.4-1 SNUBBER VISUAL INSPECTION INTERVAL

NUMBER OF UNACCEPTABLE SNUBBERS

Population Column A Column B Column C or Category Extend Interval Repeat Interval Reduce Interval (Notes 1 and 2) (Notes 3 and 6) (Notes 4 and 6) (Notes 5 and 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 or greater 29 56 109 ___ Note 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. These catergories 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.

Note 2: Interpolation between population or category sizes 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 determined by

interpolation. Note 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.

Note 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 interval shall be the same as the previous interval.

LIMERICK - UNIT 1 3/4 7-11a Amendment No. 51

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TABLE 4.7.4-1 (continued) SNUBBER VISUAL INSPECTION INTERVAL

Note 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.

Note 6: The provisions of Specification 4.0.2 are applicable for all

inspection intervals up to and including 48 months.

LIMERICK - UNIT 1 3/4 7-11b Amendment No. 51

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PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) c. Visual Inspection Acceptance Criteria Visual inspections shall verify (1) that there are no visible indications

of damage or impaired OPERABILITY, (2) attachments to the foundation or supporting structure are secure, and (3) fasteners for attachment of the snubber to the component and to the snubber anchorage 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, providing that: (1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers irrespective of type on that system that may be generically susceptible; and/or (2) the affected snubber is functionally tested in the as found condition and determined OPERABLE per Specifications 4.7.4f. For those snubbers common to more than one system, the OPERABILITY of such snubbers shall be considered in assessing the surveillance schedule for each of the related systems. A review and evaluation shall be performed and documented to justify continued operation with an unacceptable snubber. If continued operation cannot be justified, the snubber shall be declared inoperable and the ACTION requirements shall be met.

d. Transient Event Inspection An inspection shall be performed of all snubbers attached to sections of

systems that have experienced unexpected, potentially damaging transients, as determined from a review of operational data or a visual inspection of the systems, within 72 hours for accessible systems and 6 months for inaccessible systems following this determination. In addition to satisfying the visual inspection acceptance criteria, freedom-of-motion of mechanical snubbers shall be verified using at least one of the following: (1) manually induced snubber movement; or (2) evaluation of in-place snubber piston setting; or (3) stroking the mechanical snubber through its full range of travel.


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THE INFORMATION FROM TECHNICAL SPECIFICATIONS SECTION 4.7.4.d HAS BEEN RELOCATED TO THE TECHNICAL REQUIREMENTS MANUAL (TRM) SNUBBERS SECTION. TECHNICAL SPECIFICATIONS SECTIONS 4.7.4.a THROUGH 4.7.4.i HAVE BEEN INTENTIONALLY OMITTED.

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PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) e. Functional Tests At least once per 24 months a representative sample of each type ofsnubber

shall be tested using the following sample plans. The sample plan(s) shall be selected for each type prior to the test period and cannot be changed during the test period. The NRC Regional Administrator shall be notified in writing of the sample plan(s) selected for each type prior to the test period or the sample plan(s) used in the prior test period shall be implemented:

1) At least 13.3% of the total population of a snubber type shall be

functionally tested. For each snubber of that type that does not meet the functional test acceptance criteria of Specification 4.7.4f., an additional sample of at least 1/2 the size of the initial sample shall be tested until the total number tested is equal to the initial sample multiplied by the factor, 1+C/2, where C is the total number of unacceptable snubbers or until all the snubbers of that type have been tested; or

2) A representative sample of 37 snubbers of a snubber type shall be

functionally tested in accordance with Figure 4.7.4-1. "C" is the total number of snubbers of that type found not meeting the acceptance requirements of Specification 4.7.4f. The cumulative number of snubbers of the type tested is denoted by "N". If at any time the point plotted falls in the "Accept" region, testing of snubbers of that type may be terminated. When the point plotted lies in the "Continue Testing" region, additional snubbers of that type shall be tested until the point falls in the "Accept" region, or all the snubbers of that type have been tested.

LIMERICK - UNIT 1 3/4 7-13 Amendment No. 28, 54, 81

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PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) The representative sample selected for the function test sample plans

shall be randomly selected from the snubbers of each type 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 size, and capacity of snubbers of that type. Snubbers placed in the same locations as snubbers which failed in the previous functional test period shall be retested at the time of the next functional test period but shall not be included in the sample plan, and failure of this functional test shall not be the sole cause for increasing the sample size under the sample plan. Testing equipment failure during functional testing may invalidate the day's testing and allow that day's testing to resume anew at a later time provided all snubbers tested with the failed equipment during the day of equipment failure are retested.

If during the functional testing, additional testing is required due to

failure of snubbers, the unacceptable snubbers may be catergorized into failure mode group(s). A failure mode group shall include all unacceptable snubbers that have a given failure mode and all other snubbers subject to the same failure mode. Once a failure mode group has been established, it can be separated for continued testing apart from the general population of snubbers. However, all unacceptable snubbers in the failure mode group shall be counted as one unacceptable snubber for additional testing in the general population. Testing in the failure mode group shall be based on the number of unacceptable snubbers and shall continue in accordance with the sample plan selected for the type or until all snubbers in the failure mode group have been tested. Any additional unacceptable snubbers found in the failure mode group shall be counted for continued testing only for that test failure mode group. In the event that a snubber(s) becomes included in more than one test failure mode group, it shall be counted in each failure mode group and shall be subject to the corrective action of each test failure mode group.

f. 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; 2) Snubber bleed, or release rate where required, is present in both

tension and compression, within the specified range (hydraulic snubbers only);

3) For mechanical snubbers, 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.


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PLANT SYSTEMS SURVEILLANCE REQUIREMENTS (Continued) 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.

g. 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 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.

h. Functional Testing of Repaired and Replaced Snubbers 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 result 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.

i. Snubber Service Life Replacement Program The service life of all snubbers shall be monitored to ensure that the

service life is not exceeded between surveillance inspections. The maximum expected service life for various seals, springs, and other critical parts shall be extended or shortened based on monitored test results and failure history. Critical parts shall be replaced so that the maximum service life will not be exceeded during a period when the snubber is required to be OPERABLE. The parts replacements shall be documented and the documentation shall be retained in accordance with Specification 6.10.3.


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Figure 4.7.4-1

SAMPLE PLAN 2) FOR SNUBBER FUNCTIONAL TEST


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ADMINISTRATIVE CONTROLS PROCEDURES AND PROGRAMS (Continued)

i. Battery Monitoring and Maintenance Program

This Program provides for restoration and maintenance, based on the recommendations of IEEE Standard 450, “IEEE Recommended Practice for Maintenance, Testing, and Replacement of Vented Lead-Acid Batteries For Stationary Applications,” of the following:

a. Actions to restore battery cells with float voltage < 2.13 volts, and

b. Actions to equalize and test battery cells that have been discovered with electrolyte level below the minimum established design limit.

j. Surveillance Frequency Control Program

This program provides controls for Surveillance Frequencies. The program shall ensure that Surveillance Requirements specified in the TechnicalSpecifications are performed at intervals sufficient to assure the associated Limiting Conditions for Operation are met.

a. The Surveillance Frequency Control Program shall contain a list of Frequencies of those Surveillance Requirements for which the Frequency is controlled by the program.

b. Changes to the Frequencies listed in the Surveillance Frequency Control Program shall be made in accordance with NEI 04-10, “Risk-Informed Method for Control of Surveillance Frequencies,”Revision 0.

c. The provisions of Surveillance Requirements 4.0.2 and 4.0.3 are applicable to the Frequencies established in the Surveillance Frequency Control Program.

LIMERICK - UNIT 1 6-14d Amendment No. 164, 186

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INSERT: k. Snubber Program This program conforms to the examination, testing, and service life monitoring for dynamic restraints (snubbers) in accordance with 10 CFR 50.55a inservice inspection (ISI) requirements for supports. The program shall be in accordance with the following: a. This program shall meet 10 CFR 50.55a ISI requirements for supports. b. The program shall meet the requirements for ISI of supports set forth in subsequent editions of the Code of Record and addenda of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code and the ASME Code for Operation and Maintenance of Nuclear Power Plants (OM Code) that are incorporated by reference in 10 CFR 50.55a, subject to its limitations and modifications, and subject to Commission approval. c. The program shall, as allowed by 10 CFR 50.55a, meet Subsection ISTA, "General Requirements," and Subsection ISTD, "Preservice and Inservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water Reactor Nuclear Power Plants," in lieu of Section XI of the ASME B&PV Code ISI requirements for snubbers, or meet authorized alternatives pursuant to 10 CFR 50.55a. d. The 120-month program updates shall be made in accordance with 10 CFR 50.55a subject to the limitations and conditions listed therein.

PLANT SYSTEMS

3/4.7.4 SNUBBERS

LIMITING CONDITION FOR OPERATION

3.7.4 All snubbers shall be OPERABLE.

APPLICABILITY: OPERATIONAL CONDITIONS 1, 2, and 3. OPERATIONAL CONDITIONS 4 and 5 for snubbers located on systems required OPERABLE in those OPERATIONAL CONDITIONS.

ACTION:

With one or more snubbers inoperable on any system, within 72 hours replace or restore the inoperable snubber(s) to OPERABLE status and perform an engineering evaluation per Specification 4.7.4g on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for that system.

SURVEILLANCE REQUIREMENTS

4.7.4 Each snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the requirements of Specification 4.0.5.

a. Inspection Types

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

b. Visual Inspections

Snubbers are categorized as inaccessible or accessible during reactor operation. Each of these categories (inaccessible and accessible) may be inspected independently according to the schedule determined by Table 4.7.4-1. The visual inspection interval for each type of snubber shall be determined based upon the criteria provided in Table 4.7.4-1 and the first inspection interval determined using this criteria shall be based upon the previous inspection interval as established by the requirements in effect before amendment no. 15.

LIMERICK - UNIT 2 3/4 7-11 Amendment No. 1, 15

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Snubber Program.

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the Snubber Program

TABLE 4.7.4-1SNUBBER VISUAL INSPECTION INTERVAL

NUMBER OF UNACCEPTABLE SNUBBERS

Population Column A Column B Column C or Category Extend Interval Repeat Interval Reduce Interval (Notes 1 and 2) (Notes 3 and 6) (Notes 4 and 6) (Notes 5 and 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 or greater 29 56 109

Note 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. These catergories 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.

Note 2: Interpolation between population or category sizes 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 determined by interpolation.

Note 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.

Note 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 interval shall be the same as the previous interval.

LIMERICK - UNIT 2 3/4 7-11a Amendment No. 15

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TABLE 4.7.4-1 (continued)SNUBBER VISUAL INSPECTION INTERVAL

Note 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.

Note 6: The provisions of Specification 4.0.2 are applicable for all inspection intervals up to and including 48 months.

LIMERICK - UNIT 2 3/4 7-11b Amendment No. 15

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PLANT SYSTEMS

SURVEILLANCE REQUIREMENTS (Continued)

c. Visual Inspection Acceptance Criteria

Visual inspections shall verify (1) that there are no visible indications of damage or impaired OPERABILITY, (2) attachments to the foundation or supporting structure are secure, and (3) fasteners for attachment of the snubber to the component and to the snubber anchorage 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, providing that: (1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers irrespective of type on that system that may be generically susceptible; and/or (2) the affected snubber is functionally tested in the as found condition and determined OPERABLE per Specifications 4.7.4f. For those snubbers common to more than one system, the OPERABILITY of such snubbers shall be considered in assessing the surveillance schedule for each of the related systems. A review and evaluation shall be performed and documented to justify continued operation with an unacceptable snubber. If continued operation cannot be justified, the snubber shall be declared inoperable and the ACTIONS requirements shall be met.

d. Transient Event Inspection

An inspection shall be performed of all snubbers attached to sections of systems that have experienced unexpected, potentially damaging transients, as determined from a review of operational data or a visual inspection of the systems, within 72 hours for accessible systems and 6 months for inaccessible systems following this determination. In addition to satisfying the visual inspection acceptance criteria, freedom-of-motion of mechanical snubbers shall be verified using at least one of the following: (1) manually induced snubber movement; or (2) evaluation of in-place snubber piston setting; or (3) stroking the mechanical snubber through its full range of travel.


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THE INFORMATION FROM TECHNICAL SPECIFICATIONS SECTION 4.7.4.d HAS BEEN RELOCATED TO THE TECHNICAL REQUIREMENTS MANUAL (TRM) SNUBBERS SECTION. TECHNICAL SPECIFICATIONS SECTIONS 4.7.4.a THROUGH 4.7.4.i HAVE BEEN INTENTIONALLY OMITTED.

PLANT SYSTEMS


e. Functional Tests

At least once per 24 months a representative sample of each type ofsnubber shall be tested using the following sample plans. The sample plan(s) shall be selected for each type prior to the test period and cannot be changed during the test period. The NRC Regional Administrator shall be notified in writing of the sample plan(s) selected for each type prior to the test period or the sample plan(s) used in the prior test period shall be implemented:

1) At least 13.3% of the total population of a snubber type shall be functionally tested. For each snubber of that type that does not meet the functional test acceptance criteria of Specification 4.7.4f., an additional sample of at least 1/2 the size of the initial sample shall be tested until the total number tested is equal to the initial sample multiplied by the factor, 1+C/2, where C is the total number of unacceptable snubbers or until all the snubbers of that type have been tested; or

2) A representative sample of 37 snubbers of a snubber type shall be functionally tested in accordance with Figure 4.7.4-1. "C" is the total number of snubbers of that type found not meeting the acceptance requirements of Specification 4.7.4f. The cumulative number of snubbers of the type tested is denoted by "N". If at any time the point plotted falls in the "Accept" region, testing of snubbers of that type may be terminated. When the point plotted lies in the "Continue Testing" region, additional snubbers of that type shall be tested until the point falls in the "Accept" region, or all the snubbers of that type have been tested.

LIMERICK - UNIT 2 3/4 7-13 Amendment No. 19, 42

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PLANT SYSTEMS


The representative sample selected for the function test sample plans shall be randomly selected from the snubbers of each type 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 size, and capacity of snubbers of that type. Snubbers placed in the same locations as snubbers which failed in the previous functional test period shall be retested at the time of the next functional test period but shall not be included in the sample plan, and failure of this functional test shall not be the sole cause for increasing the sample size under the sample plan. Testing equipment failure during functional testing may invalidate the day's testing and allow that day's testing to resume anew at a later time provided all snubbers tested with the failed equipment during the day of equipment failure are retested.

If during the functional testing, additional testing is required due to failure of snubbers, the unacceptable snubbers may be catergorized into failure mode group(s). A failure mode group shall include all unacceptable snubbers that have a given failure mode and all other snubbers subject to the same failure mode. Once a failure mode group has been established, it can be separated for continued testing apart from the general population of snubbers. However, all unacceptable snubbers in the failure mode group shall be counted as one unacceptable snubber for additional testing in the general population. Testing in the failure mode group shall be based on the number of unacceptable snubbers and shall continue in accordance with the sample plan selected for the type or until all snubbers in the failure mode group have been tested. Any additional unacceptable snubbers found in the failure mode group shall be counted for continue testing only for that test failure mode group. In the event that a snubber(s) becomes included in more than one test failure mode group, it shall be counted in each failure mode group and shall be subject to the corrective action of each test failure mode group.

f. 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;

2) Snubber bleed, or release rate where required, is present in both tension and compression, within the specified range (hydraulic snubbers only);

3) For mechanical snubbers, 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.


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PLANT SYSTEMS


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.

g. 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 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.

h. Functional Testing of Repaired and Replaced Snubbers

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 result 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.

i. Snubber Service Life Replacement Program

The service life of all snubbers shall be monitored to ensure that the service life is not exceeded between surveillance inspections. The maximum expected service life for various seals, springs, and other critical parts shall be extended or shortened based on monitored test results and failure history. Critical parts shall be replaced so that the maximum service life will not be exceeded during a period when the snubber is required to be OPERABLE. The parts replacements shall be documented and the documentation shall be retained in accordance with Specification 6.10.3.


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Figure 4.7.4-1

SAMPLE PLAN 2) FOR SNUBBER FUNCTIONAL TEST


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ADMINISTRATIVE CONTROLS

PROCEDURES AND PROGRAMS (Continued)

i. Battery Monitoring and Maintenance Program

This Program provides for restoration and maintenance, based on the recommendations of IEEE Standard 450, “IEEE Recommended Practice for Maintenance, Testing, and Replacement of Vented Lead-Acid Batteries For Stationary Applications,” of the following:

a. Actions to restore battery cells with float voltage < 2.13 volts, and

b. Actions to equalize and test battery cells that have been discovered with electrolyte level below the minimum established design limit.

j. Surveillance Frequency Control Program

This program provides controls for Surveillance Frequencies. The Program shall ensure that Surveillance Requirements specified in the Technical Specifications are performed at intervals sufficient to assure the associated Limiting Conditions for Operation are met.

a. The Surveillance Frequency Control Program shall contain a list of Frequencies of those Surveillance Requirements for which the Frequency is controlled by the program.

b. Changes to the Frequencies listed in the Surveillance Frequency Control Program shall be made in accordance with NEI 04-10, “Risk-Informed Method for Control of Surveillance Frequencies,” Revision 0.

c. The provisions of Surveillance Requirements 4.0.2 and 4.0.3 are applicable to the Frequencies established in the Surveillance Frequency Control Program.

LIMERICK - UNIT 2 6-14d Amendment No. 126, 147

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INSERT: k. Snubber Program This program conforms to the examination, testing, and service life monitoring for dynamic restraints (snubbers) in accordance with 10 CFR 50.55a inservice inspection (ISI) requirements for supports. The program shall be in accordance with the following: a. This program shall meet 10 CFR 50.55a ISI requirements for supports. b. The program shall meet the requirements for ISI of supports set forth in subsequent editions of the Code of Record and addenda of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code and the ASME Code for Operation and Maintenance of Nuclear Power Plants (OM Code) that are incorporated by reference in 10 CFR 50.55a, subject to its limitations and modifications, and subject to Commission approval. c. The program shall, as allowed by 10 CFR 50.55a, meet Subsection ISTA, "General Requirements," and Subsection ISTD, "Preservice and Inservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water Reactor Nuclear Power Plants," in lieu of Section XI of the ASME B&PV Code ISI requirements for snubbers, or meet authorized alternatives pursuant to 10 CFR 50.55a. d. The 120-month program updates shall be made in accordance with 10 CFR 50.55a subject to the limitations and conditions listed therein.

ATTACHMENT 3

Markup of Technical Specifications Bases Page (For Information Only)




REVISED TECHNICAL SPECIFICATIONS BASES PAGES

Unit 1 TS Bases Pages B 3/4 7-2 B 3/4 7-3

Unit 2 TS Bases Pages

B 3/4 7-2 B 3/4 7-3

PLANT SYSTEMS BASES 3/4.7.4 SNUBBERS 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 Technical Specification would be of a different type, as would hydraulic snubbers from either manufacturer. A list of individual snubbers with detailed information of snubber location and size and of system affected shall be available at the plant in accordance with Section 50.71(c) of 10 CFR Part 50. The accessibility of each snubber shall be determined and approved by the Plant Operations Review Committee. The determination shall be based upon the existing radiation levels and the expected time to perform a visual inspection in each snubber location as well as other factors associated with accessibility during plant operations (e.g., temperature, atmosphere, location, etc.), and the recommendations of Regulatory Guides 8.8 and 8.10. The addition or deletion of any snubber shall be made in accordance with Section 50.59 of 10 CFR Part 50. The visual inspection schedule is based on the number of unacceptable snubbers found during the previous inspection in proportion to the sizes of the various snubber populations or categories. The visual inspection interval is based on a fuel cycle of up to 24 months and may be as long as two fuel cycles or 48 months depending on the number of unacceptable snubbers found during the previous visual inspection. The visual inspection schedule provides confidence that a constant level of snubber protection is being maintained and generally allows performance of visual inspections and corrective actions during plant outages. 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 required a shorter inspection interval will override the previous schedule. A snubber is considered inoperable if it fails the acceptance criteria of the visual inspection.

LIMERICK - UNIT 1 B 3/4 7-2 Amendment No. 27, 40, 51

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The "Snubber Program" manages the requirement for demonstrating snubber operability (examination, testing and service life monitoring) as reflected in TS Section 6.8.4.k thereby ensuring the TS remains consistent with the ISI program. The program for in service testing of snubbers in accordance with ASME OM Code and the applicable addenda as required by 10 CFR 50.55a(g) is required to include evaluation of supported components/systems when snubbers are found to be inoperable.

PLANT SYSTEMS BASES SNUBBERS (Continued) To provide assurance of snubber functional reliability one of two functional testing methods is used with the stated acceptance criteria: 1. Functionally test 13.3% sample of a type of snubber with an additional 1/2

sample tested for each functional testing failure, or 2. Functionally test 37 snubbers and determine sample acceptance using

Figure 4.7.4-1. Functional Testing sample plans are based on ASME/ANSI OMc-1990 Addenda to ASME/ANSI OM-1987, Part 4. Figure 4.7.4-1 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 Commission if a justifiable basis for exemption is presented and, if applicable, snubber life destructive testing was performed to qualify the snubbers for the applicable design conditions at either the completion of their fabrication or at a subsequent date. Snubbers so exempted shall be listed in the list of individual snubbers indicating the extent of the exemptions. The service life of a snubber is evaluated via manufacturer input and information through consideration of the snubber service conditions and associated installation and maintenance records (i.e., 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. 3/4.7.5 SEALED SOURCE CONTAMINATION The limitations on removable contamination for sources requiring leak testing, including alpha emitters, is based on 10 CFR 70.39(c) limits for plutonium. This limitation will ensure that leakage from byproduct, source, and special nuclear material sources will not exceed allowable intake values. Sealed sources are classified into three groups according to their use, with surveillance requirements commensurate with the probability of damage to a source in that group. Those sources which are frequently handled are required to be tested more often than those which are not. Sealed sources which are continuously enclosed within a shielded mechanism, i.e,, sealed sources within radiation monitoring devices, are considered to be stored and need not be tested unless they are removed from the shielded mechanism. LIMERICK - UNIT 1 B 3/4 7-3 Amendment No. 54, 81

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PLANT SYSTEMS BASES 3/4.7.4 SNUBBERS 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 Technical Specification would be of a different type, as would hydraulic snubbers from either manufacturer. A list of individual snubbers with detailed information of snubber location and size and of system affected shall be available at the plant in accordance with Section 50.71(c) of 10 CFR Part 50. The accessibility of each snubber shall be determined and approved by the Plant Operations Review Committee. The determination shall be based upon the existing radiation levels and the expected time to perform a visual inspection in each snubber location as well as other factors associated with accessibility during plant operations (e.g., temperature, atmosphere, location, etc.), and the recommendations of Regulatory Guides 8.8 and 8.10. The addition or deletion of any snubber shall be made in accordance with Section 50.59 of 10 CFR Part 50. The visual inspection schedule is based on the number of unacceptable snubbers found during the previous inspection in proportion to the sizes of the various snubber populations or categories. The visual inspection interval is based on a fuel cycle of up to 24 months and may be as long as two fuel cycles or 48 months depending on the number of unacceptable snubbers found during the previous visual inspection. The visual inspection schedule provides confidence that a constant level of snubber protection is being maintained and generally allows performance of visual inspections and corrective actions during plant outages. 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 required a shorter inspection interval will override the previous schedule. A snubber is considered inoperable if it fails the acceptance criteria of the visual inspection. LIMERICK - UNIT 2 B 3/4 7-2 Amendment No. 15

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The "Snubber Program" manages the requirement for demonstrating snubber operability (examination, testing and service life monitoring) as reflected in TS Section 6.8.4.k thereby ensuring the TS remains consistent with the ISI program. The program for in service testing of snubbers in accordance with ASME OM Code and the applicable addenda as required by 10 CFR 50.55a(g) is required to include evaluation of supported components/systems when snubbers are found to be inoperable.

PLANT SYSTEMS BASES SNUBBERS (Continued) To provide assurance of snubber functional reliability one of two functional testing methods is used with the stated acceptance criteria: 1. Functionally test 13.3% sample of a type of snubber with an additional 1/2

sample tested for each functional testing failure, or 2. Functionally test 37 snubbers and determine sample acceptance using

Figure 4.7.4-1. Functional Testing sample plans are based on ASME/ANSI OMc-1990 Addenda to ASME/ANSI OM-1987, Part 4. Figure 4.7.4-1 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 Commission if a justifiable basis for exemption is presented and, if applicable, snubber life destructive testing was performed to qualify the snubbers for the applicable design conditions at either the completion of their fabrication or at a subsequent date. Snubbers so exempted shall be listed in the list of individual snubbers indicating the extent of the exemptions. The service life of a snubber is evaluated via manufacturer input and information through consideration of the snubber service conditions and associated installation and maintenance records (i.e., 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. 3/4.7.5 SEALED SOURCE CONTAMINATION The limitations on removable contamination for sources requiring leak testing, including alpha emitters, is based on 10 CFR 70.39(c) limits for plutonium. This limitation will ensure that leakage from byproduct, source, and special nuclear material sources will not exceed allowable intake values. Sealed sources are classified into three groups according to their use, with surveillance requirements commensurate with the probability of damage to a source in that group. Those sources which are frequently handled are required to be tested more often than those which are not. Sealed sources which are continuously enclosed within a shielded mechanism, i.e,, sealed sources within radiation monitoring devices, are considered to be stored and need not be tested unless they are removed from the shielded mechanism. LIMERICK - UNIT 2 B 3/4 7-3 Amendment No. 19, 42

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ATTACHMENT 4

TS 4.7.4 Surveillance Requirements Comparison to ASME OM Code Subsection ISTD




Attachment 4 toLGS LAR to Revise Snubber SR

LGS Snubber TS vs. OM Code ISTD Comparison Page 1 of 9

Limerick Generating Station Technical Specification (TS)

ASME OM Code 2004 Edition through 2006 Addenda - Subsection ISTD

Justification for Change

3.7.4 LIMITING CONDITION FOR OPERATIONAPPLICABILITY: OPERATIONAL CONDITIONS 1, 2, and 3. OPERATIONAL CONDITIONS 4 and 5 for snubbers located on systems required OPERABLE in those OPERATIONAL CONDITIONS.

Not Applicable Site operating conditions are not specified in the OM code.

3.7.4 LIMITING CONDITION FOR OPERATIONACTION: With one or more snubbers inoperable on any system, within 72 hours replace or restore the inoperable snubber(s) to OPERABLE status and perform an engineering evaluation per Specification 4.7.4g on the attached component or declare the attached system inoperable and follow the appropriate ACTION statement for thatsystem.

ISTD-4280 Inservice Examination Corrective Action. Unacceptable snubbers shall be adjusted, repaired, modified, or replaced. Additional action regarding the examination interval shall be taken as indicated in Table ISTD-4252-1.

Subsection ISTD does not set a timeframe to replace or restore inoperable snubbers. The 72 hour allowance to replace or restore the inoperable snubber to OPERABLE status will be retained in the TS 3.7.4 ACTION statement.

4.7.4 SURVEILLANCE REQUIREMENTS Each snubber shall be demonstrated OPERABLE by performance of the following augmented inservice inspection program and the requirements of Specification 4.0.5.

ASME OM Code - Subsection ISTD - Preservice and Inservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water Reactor Nuclear Power Plant.

LGS Snubber Program will be theinspection program used toensure operability for snubbersby following the ASME OMCode Subsection ISTD.

4.7.4a Inspection TypesAs used in this specification, type of snubber shall mean snubbers of the same design and manufacturer, irrespective of capacity.

While ISTD does not have a generic definition like this, ISTD-4220(a) definesfor visual exams what your grouping/definition can be for visuals and ISTD-5250 describes the requirements for Defined Test Plan Groups for selecting /scheduling functional tests.

Refer to TS 4.7.4b VisualInspections, and TS 4.7.4eFunctional Testing sectionsbelow.

4.7.4b Visual InspectionsSnubbers are categorized as inaccessible or accessible during reactor operation. Each of these categories (inaccessible and accessible) may be inspected independently according to the schedule determined by Table 4.7.4-1. The visual inspection interval for each type of snubber shallbe determined based upon the criteria provided in Table 4.7.4-1 and the first inspection interval determined using this criteria shall be based upon the previous inspection interval as established by the requirements in effect before amendment no. 51.

ISTD-4220(a) requires all snubbers to be considered one population for examination, or they may be categorized as accessible and inaccessible.

ISTD-4220(b) requires the decision to examine the snubbers as one population or as separate categories shall be made and documented before the scheduled examination begins and shall not be changed during the examination.

ISTD-4252(b) requires inservice examinations to be conducted in accordance with Table ISTD-4252-1.

Table ISTD-4252-1 is equivalent to TS Table 4.7.4-1 for all population/category sizes; therefore, use of ISTD-4200 for snubber inservice examination in lieu of current TS 4.7.4b does not change the number of snubbers required to be examined or the required examination intervals.






4.7.4c Visual Inspection Acceptance CriteriaVisual inspections shall verify (1) that there are no visible indications of damage or impaired OPERABILITY, (2) attachments to the foundation or supporting structure are secure, and (3) fasteners for attachment of the snubber to the component and to the snubber anchorage are secure.

ISTD-4210 states that inservice examination shall be a visual examination to identify physical damage, leakage, corrosion, or degradation that may have been caused by environmental exposure or operating conditions; and external characteristics that may indicate operational readiness of the snubber shall be examined.

ISTD-4231 requires that examinations shall include observations for the following and the conditions shall be evaluated when found:(a) loose fasteners, or members that are corroded or deformed(b) disconnected components or other conditions that might interfere with the proper restraint of movement.

ISTD-4232 requires that examinations verify snubbers do not restrain thermal movement to an extent that unacceptable stresses could develop in the snubber, the pipe, or other equipment that the XI, snubber is designed to protect or restrain. There should be no indication of binding, misalignment or deformation of the snubber.

ISTD-4233 requires that examinations verify snubbers shall be free of defects that may be generic to particular designs as may be detected by visual examination.

ASME Section XI, IWF-1300 and Figure IWF-1300-1 (f) requires integral and nonintegral attachments for snubbers shall be examined in accordance with the requirements of Subsection IWF.

10 CFR 50.55a(b)(3)(v)(B) allows the use of Subsection ISTD for inservice examination requirements. Preservice and inservice examinations are required to be performed using the VT -3 visual examination method described in ASME Section XI, IWA-2213.

The revised ISI program requirements for inservice examination do not differ significantly from the visual inspection acceptance criteria in TS 4.5.M.1.b.

Examination of the snubber from pin-to-pin in accordance with ASME OM Code Subsection ISTD and the attachments to the component or structure will be examined in accordance with ASME Section XI, Subsection IWF. This will encompass that which was examined in accordance with the LGS TS.






4.7.4d Transient Event InspectionAn inspection shall be performed of all snubbers attached to sections of systems that have experienced unexpected, potentially damaging transients, as determined from a review of operational data or a visual inspection of the systems, within 72 hours for accessible systems and 6 months for inaccessible systems following this determination. In addition to satisfying the visual inspection acceptance criteria, freedom-of-motion of mechanical snubbers shall be verified using at least one of the following: (1) manually induced snubber movement; or (2) evaluation of in-place snubber piston setting; or (3) stroking the mechanical snubber through its full range of travel.

ISTD-1750 Transient Dynamic Event. If there is an unanticipated transient event that may have effected a snubber's operability, the snubber and system shall be reviewed and any required corrective action should be performed. These actions shall be independent of the requirements of ISTD-4100, ISTD-4200, ISTD-5100, and ISTD-5200.

The revised ISI program requirements for evaluation and corrective action for inservice examination are equivalent to those of current TS 4.7.4d for Transient Event Inspection and meet the requirements of ISTD. Specification 4.7.4d requirement of performing a Transient Event Inspection will be removed and incorporated into the Technical Requirements Manual.

4.7.4c Visual Inspection Acceptance Criteria (continued)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, providing that: (1) the cause of the rejection is clearly established and remedied for that particular snubber and for other snubbers irrespective of type on that system that may be generically susceptible; and/or (2) the affected snubber is functionally tested in the as found condition and determined OPERABLE per Specifications 4.7.4f. For those snubbers common to more than one system, the OPERABILITY of such snubbers shall be considered in assessing the surveillance schedule for each of the related systems. A review and evaluation shall be performed and documented to justify continued operation with an unacceptable snubber. If continued operation cannot be justified, the snubber shall be declared inoperable and the ACTION requirements shall be met.

ISTD-4240 permits snubbers classified as unacceptable during inservice examination to be tested in accordance with the requirements of ISTD-5210. Results that satisfy the operational readiness test criteria of ISTD-5210 shall be used to accept the snubber, provided the test demonstrates that the unacceptable condition did not affect operational readiness.

ISTD-4233 requires that fluid supply or content for hydraulic snubbers shall be observed. If the fluid is less than the minimum amount, the installation shall be identified as unacceptable, unless a test establishes that the performance of the snubber is within specified limits. Tests shall be performed in accordance with ISTD-5210. The initial test shall start with the piston at the as-found setting and be performed in the extension (tension) direction, or in a mode that more closely resembles the operating and design requirements of the snubber.

ISTD-4270 requires that snubbers that do not meet examination requirements of ISTD-4230 shall be evaluated to determine the root cause of the unacceptability.

ISTD-4280 requires that unacceptable snubbers shall be adjusted, repaired, modified, or replaced.

ISTD-1800 requires that an evaluation shall be performed of the system(s) or components of which an unacceptable snubber is a part, for possible damage to the supported system or component.

The revised ISI program requirements for evaluation and corrective action for inservice examination are equivalent to those of current TS 4.7.4c for visual examination acceptance criteria and meet the requirements of ISTD.






4.7.4e Functional TestsAt least once per 24 months a representative sample of each type of snubber shall be tested using the following sample plans. The sample plan(s) shall be selected for each type prior to the test period and cannot be changed during the test period. The NRC Regional Administrator shall be notified in writing of the sample plan(s) selected for each type prior to the test period or the sample plan(s) used in the prior test period shall be implemented:

1) At least 13.3% of the total population of a snubber type shall be functionally tested. For each snubber of that type that does not meet the functional test acceptance criteria of Specification 4.7.4f., an additional sample of at least 1/2 the size of the initial sample shall be tested until the total number tested is equal to the initial sample multiplied by the factor, 1+C/2, where C is the total number of unacceptable snubbers or until all the snubbers of that type have been tested; or

2) A representative sample of 37 snubbers of a snubber type shall be functionally tested in accordance with Figure 4.7.4-1. "C" is the total number of snubbers of that type found not meeting the acceptance requirements of Specification 4.7.4f. The cumulative number of snubbers of the type tested is denoted by "N". If at any time the point plotted falls in the "Accept" region, testing of snubbers of that type may be terminated. When the point plotted lies in the "Continue Testing" region, additional snubbers of that type shall be tested until the point falls in the "Accept" region, or all the snubbers of that type have been tested.

ISTD-5252 Defined Test Plan Group (DTPG) Alternatives. Except as required by ISTD-5253, the total snubber population may be considered one DTPG, or alternatively, differences in design, application, size, or type may be considered in establishing DTPGs.

ISTD-5200 requires snubber operational readiness testing to be performed each fuel cycle. Testing shall be performed during normal system operation, or during system or plant outages.

ISTD-5240 states that snubber testing may begin no earlier than 60 days before a scheduled refueling outage.

ISTD-5261 requires snubbers of each DTPG to be tested using either:

(a) the 10% testing sample plan(b) the 37 testing sample plan

ISTD-5223 and ISTD-5224 permit snubbers to be tested in their installed location or in a bench test.

ISTD-5271 requires snubbers that do not meet test requirements specified in ISTD-5210 or ISTD-5230 to be evaluated to determine the root cause of the failure.

ISTD-5330 requires the snubbers of each DTPG and Failure Mode Group (FMG) to be tested as required. Testing is complete when the mathematical expressions of ISTD-5331 are satisfied, or all snubbers in the DTPG or FMG have been tested.

ISTD-5331 requires that testing shall satisfy the mathematical expressions as follows:

(a) for each DTPGN ≥ 0.1n + C(0.1 n/2)(b) for each FMGNF ≥ CF(0.1 n/2)

Per ISTD-5322, additional tests are notrequired for an isolated failure.

The frequency of snubber testing in the revised program is slightly changed from the frequency specified in current TS 4.7.4e.

The TS requirement of 13.3% is changed to a 10% requirement in the revised program of a snubber population.

The revised program provides greater flexibility in permitting testing to be performed during modes other than shutdown. However, as noted in Generic Letter 91-04:

"The staff concludes that the TS need not restrict surveillances as only being performed during shutdown. Nevertheless, safety dictates that when refueling interval surveillances are performed during power operation, licensees give proper regard for their effect on the safe operation of the plant. If the performance of a refueling interval surveillance during plant operation would adversely affect safety, the licensee should postpone the surveillance until the unit is shut down for refueling or is in a condition or mode that is consistent with the safe conduct of that surveillance."






4.7.4e Functional Tests (continued)The representative sample selected for the function test sample plans shall be randomly selected from the snubbers of each type 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 size, and capacity of snubbers of that type. Snubbers placed in the same locations as snubbers which failed in the previous functional test period shall be retested at the time of the next functional test period but shall not be included in the sample plan, and failure of this functional test shall not be the sole cause for increasing the sample size under the sample plan. Testing equipment failure during functional testing may invalidate the day's testing and allow that day's testing to resume anew at a later time provided all snubbers tested with the failed equipment during the day of equipment failure are retested.

ISTD-5311(a) requires the initial sample to include as practicable representation from the DTPG based on the significant features (i.e., the various designs, configurations, operating environments, sizes, and capacities) and based on the ratio of the number of snubbers of each significant feature, to the total number of snubbers in the DTPG. Initial sample selection shall be random.

As an alternative, ISTD-5311 (b) requires the initial sample to be generally representative, as in ISTD-5311(a) but allows the sample to be selected from those snubbers scheduled for seal replacement or other activities related to service life monitoring.

ISTD-5500 requires that snubbers placed in the same location as snubbers that failed the previous inservice operational readiness test shall be retested at the time of next operational readiness testing unless the cause of the failure is clearly established and corrected. Retests in accordance with ISTD-5500 shall not be considered a part of inservice operational readiness testing sample selection requirements.

Since the snubbers of a DTPG are of the same design, configuration, and operating environment, and only a few snubbers are of different size and capacity, the representative sample would only vary slightly.

Initial sample composition requirements are similar in the revised program than those in current TS 4.7.4e. The revised program requirements continue to ensure initial sample selection is random and representative.






4.7.4e Functional Tests (continued)If during the functional testing, additional testing is required due to failure of snubbers, the unacceptable snubbers may be categorized intofailure mode group(s). A failure mode group shall include all unacceptable snubbers that have a given failure mode and all other snubbers subject to the same failure mode. Once a failure mode group has been established, it can be separated for continued testing apart from the general population of snubbers. However, all unacceptable snubbers in the failure mode group shall be counted as one unacceptable snubber for additional testing in the general population. Testing in the failure mode group shall be based on the number of unacceptable snubbers and shall continue in accordance with the sample plan selected for the type or until all snubbers in the failure mode group have been tested. Any additional unacceptable snubbers found in the failure mode group shall be counted for continued testing only for that test failure mode group. In the event that a snubber(s) becomes included in more than one test failure mode group, it shall be counted in each failure mode group and shall be subject to the corrective action of each test failure mode group.

ISTD-5271 states that snubbers that do not meet test requirements shall be evaluated to determine the root cause of the failure.

ISTD-5272 states that snubbers found unacceptable according to operational readiness test requirements should be assigned to FMGs unless the failure is isolated or unexplained. FMGs shall include all unacceptable snubbers with the same failure mode and all other snubbers with similar potential for similar failure.

As an alternative to additional testing for design or manufacturing FMGs, ISTD-5323 requires no additional testing when all snubbers in the FMGs are replaced or modified in accordance with ISTD-1600. If replacement or modification is not performed in accordance with ISTD-5323, additional testing is required in accordance with ISTD- 5324. Testing is required to continue until the acceptance limit is satisfied or all snubbers in the FMG have been tested.

The revised program requirements for manufacturer or design deficiencies require replacement or modification of all snubbers in the FMG or additional testing until the mathematical expression of ISTD-5331(b) is satisfied or all snubbers in the FMG have been tested. This may result in fewer snubbers being tested after a test failure. However, the revised program requirements provide adequate assurance of snubber OPERABILITY because all potentially affected snubbers will be replaced or modified; or the acceptance limit for additional testing will be met, demonstrating an acceptable level of reliability.

4.7.4f Functional Test Acceptance CriteriaThe snubber functional test shall verify that:

1) Activation (restraining action) is achieved within the specified range in both tension and compression;

2) Snubber bleed, or release rate where required, is present in both tension and compression, within the specified range (hydraulic snubbers only);

3) For mechanical snubbers, 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.

ISTD-5210 Test Parameters

a) Activation is within the specified range of velocity or acceleration in tension and in compression.

b) Release rate is within the specified range in tension and in compression. For units specifically required not to displace under continuous load, ability of the snubber to withstand load without displacement.

c) For mechanical snubbers, drag force is within specified limits, in tension and in compression.

The revised snubber program requirements for hydraulic, mechanical PSA snubbers, and mechanical PSB snubbers acceptance criteria are equivalent to those of current TS 4.7.4f.






4.7.4g Functional Test Failure AnalysisAn 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 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.

ISTD-5271 states that snubbers that do not meet test requirements shall be evaluated to determine the root cause of the failure.

ISTD-1800 requires evaluation of system(s) which a failed snubber was attached to, for possible damage.

The revised snubber program requirements for functional test failure analysis are equivalent to those of current TS 4.7.4g.

4.7.4h Functional Testing of Repaired and Replaced SnubbersSnubbers 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 result shall be tested to meet the functional test criteria before installation in the unit. Mechanical snubbers shall have met theacceptance 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.

ISTD-5500 requires that snubbers placed in the same location as snubbers that failed the previous inservice operational readiness test shall be retested at the time of next operational readiness testing unless the cause of the failure is clearly established and corrected. Retests in accordance with ISTD-5500 shall not be considered a part of inservice operational readiness testing sample selection requirements.

The revised program requirement is equivalent to the current TS 4.7.4h requirement to retest a replacement snubber installed in place of a failed snubber. Retesting is required, unless the cause of the original failure was clearly established and corrected. The revised program does not require retest during the next test period of failed snubbers that are repaired and installed in another position. However, the corrective action requirements for unacceptable snubbers in ISTD-5280, including testing, provide adequate assurance of OPERABILITY for failed snubbers that are repaired and installed in another position.






4.7.4i Snubber Service Life Replacement ProgramThe service life of all snubbers shall be monitored to ensure that the service life is not exceeded between surveillance inspections. The maximum expected service life for various seals, springs, and other critical parts shall be extended or shortened based on monitored test results and failure history. Critical parts shall be replaced so that the maximum service life will not be exceeded during a period when the snubber is required to be OPERABLE. The parts replacements shall be documented and the documentation shall be retained in accordance with Specification 6.10.3.

ISTD-6100 requires initial snubber service life to be predicted based on manufacturer's recommendation or design review.

ISTD-6200 requires service life to be evaluated at least once each fuel cycle. If the evaluation indicates that service life will be exceeded before the next scheduled system or plant outage, one of the following actions shall be taken:

(a) the snubber shall be replaced with a snubber for which the service life will not be exceeded before the next scheduled system or plant outage

(b) technical justification shall be documented for extending the servicelife to or beyond the next scheduled system or plant outage

(c) the snubber shall be reconditioned such that its service life will be extended to or beyond the next scheduled system or plant outage

ISTD-6300 requires causes for any examination or testing failures shall be determined and considered in establishing or reestablishing service life.

The service life evaluation requirements in ISTD-6100, ISTD-6200 and ISTD-6300 are equivalent to the requirements in current TS 4.7.4i.

LGS TS 6.10.3 states that records of inservice inspections performed pursuant to these Technical Specifications shall be retained for the duration of the Facility Operating License. This requirement remains unchanged.






Table 4.7.4-1 SNUBBER VISUAL INSPECTION INTERVALNote 1: The next visual inspection interval for a snubber population or category size shall be determined based upon the previous inspectioninterval 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. These 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.

Note 2: Interpolation between population or category sizes 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 determined by interpolation.

Note 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.

Note 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 interval shall be the same as the previous interval.

Note 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-thirdsof 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.

Note 6: The provisions of Specification 4.0.2 are applicable for all inspection intervals up to and including 48 months.

ISTD-4220(a) requires all snubbers to be considered one population for examination, or they may be categorized as accessible and inaccessible.

ISTD-4220(b) requires the decision to examine the snubbers as one population or as separate categories shall be made and documented before the scheduled examination begins and shall not be changed during the examination.

ISTD-4252(b) requires inservice examinations to be conducted in accordance with Table ISTD-4252-1

Table ISTD-4252-1 is equivalent to TS Table 4.7.4-1 for all population/category sizes; therefore, use of ISTD in lieu of current TS is equivalent for the site.

Documents

Limerick, Units 1 and 2 - Nuclear Regulatory CommissionU.S. Nuclear Regulatory Commission License Amendment Request Revise Snubber Surveillance Requirements March 29, 2016 Page 2 In