ML073230134

License Amendment Request, Proposed One-Time Changes to Technical Specifications Section 3.4.3.1 Reactor Coolant System Leakage Detection Systems

ML073230134
Person / Time
Site:	Limerick
Issue date:	11/16/2007
From:	Cowan P Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML073230134 (18)

Text

Exelon Nuclear www.exeloncorp.com 200 Exelon Way Nuclear Kennett Square, PA 19348 10 CFR 50.90 November 16,2007 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Unit 2 Facility Operating License No. NPF-85 C D o m t NO.50-353

SUBJECT:

License Amendment Request Proposed One-Time Changes to Technical Specifications Section 3.4.3.1 Reactor Coolant System Leakage Detection Systems Pursuant to 10 CFR 50.90, Application for amendment of license or construction permit, Exelon Generation Company, LLC (Exelon), proposes one-time changes to the Technical Specifications (TS), Appendix A of Operating License No. NPF-85 for Limerick Generating Station (LGS), Unit 2.

The proposed one-time changes revise TS Limiting Condition for Operation (LCO) 3.4.3.1 Action requirements associated with inoperable reactor coolant system (RCS) leakage detection systems. In particular, a new TS Action requirement is proposed to be added that will allow the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system, other than the primary containment atmosphere gaseous radioactivity monitoring system (existing TS Action E), to be inoperable for up to 7 days. In addition, the 12-hour shutdown Action will be revised to require entry when any two or more leakage detection systems, other than Action E or the new Action, are inoperable or the individual Actions cannot be met in the allotted time. Also a footnote will be added to indicate that the proposed changes would only be effective for the remainder of the current operating cycle (Cycle lo), which is currently scheduled to end in the Spring of 2009, or until the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.

License Amendment Request One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems)

Docket No. 50-353 November 16,2007 Page 2 On April 14, 2007, it was noted that the drywell unit cooler condensate flow rate monitor increased from 1.6 to 3.2 gpm with no corresponding increase in identified or unidentified floor drain sump flow. Investigation into the increase in drywell unit cooler condensate flow determined that the "B" drywell unit cooler drain flow transmitter was saturated. In this state, the drywell unit cooler condensate flow rate monitoring system would not be able to detect a change in leakage that is required by TS. Therefore, the drywell unit cooler condensate flow rate monitoring system was declared inoperable. The flow transmitter for the "B" drywell unit cooler is located inside the drywell and would require containment entry to conduct repairs.

Therefore, the flow transmitter cannot be repaired until the next refuel outage currently scheduled for the Spring of 2009, or the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.

Existing TS LCO 3.4.3.1, Action F requires that, with any two RCS leakage detection systems inoperable, other than those specified in Action E, the unit be in Hot Shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

With the drywell unit coolers condensate flow rate monitoring system already inoperable, existing TS LCO 3.4.3.1, Action F must be entered when certain TS surveillance testing is performed on the remaining operable RCS leakage detection systems. For example, a functional test and channel calibration of the drywell floor drain sump flow monitoring system are performed once every 31 days and 6 months, respectively. During the performance of these tests, the drywell floor drain sump flow monitoring system is declared inoperable. As a result, the 12-hour shutdown Action required by existing TS LCO 3.4.3.1, Action F is entered because of both the drywell unit coolers condensate flow rate monitoring system and the drywell floor drain sump flow monitoring system being inoperable concurrently. The proposed changes include a new 7-day Action requirement that provides the ability to perform TS required surveillance testing and repairs, if necessary, on the other RCS leakage detection systems, as applicable, without being in a 12-hour shutdown Action statement because of the already inoperable drywell unit coolers condensate flow rate monitoring system. provides the evaluation of the proposed one-time changes. Attachment 2 provides the marked-up TS page indicating the proposed changes. Attachment 3 provides the marked-up TS Bases page for information only.

Exelon has concluded that the proposed changes present no significant hazards consideration under the standards set forth in 10CFR 50.92.

This amendment request contains no regulatory commitments.

Exelon requests approval of the proposed amendment by November 16, 2008. If current plant conditions change, Exelon may request NRC approval of the proposed amendment on an expedited basis. Upon NRC approval, the amendment shall be implemented within 30 days of issuance.

The proposed changes have been reviewed by the Plant Operations Review Committee and approved by the Nuclear Safety Review Board.

License Amendment Request One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems)

Docket No. 50-353 November 16,2007 Page 3 We are notifying the State of Pennsylvania of this application for changes to the Technical Specifications by transmitting a copy of this letter and its attachments to the designated State Official.

If you have any questions or require additional information, please contact Glenn Stewart at 610-765-5529.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 16th day of November, 2007.

Respectfully, Pamela B. Cowan Director, Licensing & Regulatory Affairs Exelon Generation Company, LLC Attachments: 1. Evaluation of Proposed Changes

2. Markup of Proposed Technical Specifications Page

3. Markup of Proposed Technical Specifications Bases Page cc: Regional Administrator - NRC Region I w/ attachments NRC Senior Resident Inspector - Limerick Generating Station II NRC Project Manager, NRR - Limerick Generating Station II Director, Bureau of Radiation Protection - Pennsylvania Department of Environmental Protection I1

ATTACHMENT 1 License Amendment Request Limerick Generating Station, Unit 2 Docket No. 50-353 EVALUATION OF PROPOSED CHANGES

Subject:

Proposed One-Time Changes to Technical Specifications Section 3.4.3.1 - Reactor Coolant System Leakage Detection Systems

2.0 PROPOSED CHANGE

S

7.0 REFERENCES

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 1 of 8 Docket No. 50-353 Evaluation of Proposed Changes

1.0 DESCRIPTION

Pursuant to 10 CFR 50.90, Application for amendment of license or construction permit, Exelon Generation Company, LLC (Exelon), proposes one-time changes to the Technical Specifications (TS), Appendix A of Operating License No. NPF-85 for Limerick Generating Station (LGS), Unit 2.

The proposed one-time changes revise TS Limiting Condition for Operation (LCO) 3.4.3.1 Action requirements associated with inoperable reactor coolant system (RCS) leakage detection systems. In particular, a new TS Action requirement is proposed to be added that will allow the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system, other than the primary containment atmosphere gaseous radioactivity monitoring system (existing TS Action E), to be inoperable for up to 7 days. In addition, the 12-hour shutdown Action will be revised to require entry when any two or more leakage detection systems, other than Action E or the new Action, are inoperable or the individual Actions cannot be met in the allotted time. Also a footnote will be added to indicate that the proposed changes would only be effective for the remainder of the current operating cycle (Cycle 10), which is currently scheduled to end in the Spring of 2009, or until the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.

On April 14, 2007, it was noted that the drywell unit cooler condensate flow rate monitor increased from 1.6 to 3.2 gpm with no corresponding increase in identified or unidentified floor drain sump flow. Investigation into the increase in drywell unit cooler condensate flow determined that the "B" drywell unit cooler drain flow transmitter was saturated. In this state, the drywell unit cooler condensate flow rate monitoring system would not be able to detect a change in leakage that is required by TS. Therefore, the drywell unit cooler condensate flow rate monitoring system was declared inoperable.

The flow transmitter for the "B" drywell unit cooler is located inside the drywell and would require containment entry to conduct repairs. Therefore, the flow transmitter cannot be repaired until the next refuel outage currently scheduled for the Spring of 2009, or the next shutdown of sufficient duration, whichever comes first.

Existing TS LCO 3.4.3.1, Action F requires that, with any two RCS leakage detection systems inoperable, other than those specified in Action E, the unit be in Hot Shutdown within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. With the drywell unit coolers condensate flow rate monitoring system already inoperable, existing TS LCO 3.4.3.1, Action F must be entered when certain TS surveillance testing is performed on the remaining operable RCS leakage detection systems. For example, a functional test and channel calibration of the drywell floor drain sump flow monitoring system are performed once every 31 days and 6 months, respectively. During the performance of these tests, the drywell floor drain sump flow monitoring system is declared inoperable. As a result, the 12-hour shutdown Action required by existing TS LCO 3.4.3.1, Action F is entered because of both the drywell unit coolers condensate flow rate monitoring system and the drywell floor drain sump flow monitoring system being inoperable concurrently. The proposed changes include a new 7-day Action requirement that provides the ability to perform TS required surveillance testing and repair, if necessary, on the other RCS leakage detection systems, as

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 2 of 8 Docket No. 50-353 Evaluation of Proposed Changes applicable, without being in a 12-hour shutdown Action statement because of the already inoperable drywell unit coolers condensate flow rate monitoring system.

A description and evaluation of the proposed changes are provided in this attachment.

Attachment 2 provides the marked-up TS page indicating the proposed changes.

Attachment 3 provides the marked-up TS Bases page for information only.

2.0 PROPOSED CHANGE

S The changes requested by this amendment application are described below.

1. Add new TS LCO 3.4.3.1, Action F to read: "With the drywell unit cooler condensate flow rate monitoring system inoperable and one other RCS leakage detection system inoperable, other than the primary containment atmosphere gaseous radioactivity monitoring system (ACTION E), restore at least one of the leakage detection systems to OPERABLE status within 7 days AND perform a CHANNEL CHECK of the primary containment atmosphere gaseous radioactivity monitoring system (SR 4.4.3.1.a) once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.*" The proposed changes are shown in Attachment 2.

2. Change existing TS LCO 3.4.3.1, Action F to Action G and revise it to read: "With any two or more leakage detection systems inoperable other than ACTIONS E or F*

above, OR with required Actions and associated Completion Time of ACTIONS A, B, C, D, E or F* not met, be in HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> AND in COLD SHUTDOWN within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />." These proposed changes are shown in Attachment 2.

3. Add the following footnote to Action F and Action G, as appropriate:

• ACTION F is only effective for the remainder of the current operating cycle (Cycle 10), which is currently scheduled to end in the Spring of 2009, or until the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.

4. Revise TS Bases 3/4.4.3.1 to reflect the changes proposed above. These proposed changes are provided in Attachment 3 for information only.

3.0 BACKGROUND

Limits on leakage from the reactor coolant pressure boundary (RCPB) are required so that appropriate action can be taken before the integrity of the RCPB is impaired.

Leakage detection systems for the RCS are provided to alert the operators when leakage rates above normal background levels are detected and also to supply quantitative measurement of leakage rates.

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 3 of 8 Docket No. 50-353 Evaluation of Proposed Changes Systems for separating the leakage of an identified source from an unidentified source are necessary to provide prompt and quantitative information to the operators to permit them to take immediate corrective action. At LGS, leakage from the RCPB inside the drywell is detected by at least one of four (4) independently monitored variables which include drywell drain sump level changes over time yielding drain flow rates, and drywell gaseous radioactivity, drywell unit cooler condensate flow rate and drywell pressure/temperature levels. The primary means of quantifying leakage in the drywell are the drywell floor drain sump flow monitoring system for unidentified leakage and the drywell equipment drain tank flow monitoring system for identified leakage.

The drywell floor drain sump flow monitoring system monitors unidentified leakage collected in the floor drain sump. Unidentified leakage consists of leakage from RCPB components inside the drywell which are not normally subject to leakage and otherwise routed to the drywell equipment drain sump. The primary containment floor drain sump has a transmitter that supplies level indication to the main control room via the plant monitoring system. The level instrument processing unit calculates an average leak rate (gpm) for a given measurement period which resets whenever the sump drain valve closes. The level processing unit provides an alarm to the main control room each time the average leak rate changes by a predetermined value since the last time the alarm was reset. For the drywell floor drain sump flow monitoring system, the setpoint basis is a 1 gpm change in unidentified leakage.

In addition to the drywell floor drain sump flow monitoring system described above, the discharge of each sump is monitored by an independent flow element. The measured flow rate from the flow element is integrated and recorded. A main control room alarm is also provided to indicate an excessive sump discharge measured via the flow element.

This system is not credited for drywell floor drain sump flow monitoring system operability.

The primary containment atmosphere gaseous radioactivity monitoring system continuously monitors the primary containment atmosphere for gaseous radioactivity levels. A sudden increase of radioactivity, which may be attributed to RCPB steam or reactor water leakage, is annunciated in the main control room. The primary containment atmosphere gaseous radioactivity monitoring system is not capable of quantifying leakage rates, but is sensitive enough to detect increased leakage rates of 1 gpm within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. Larger changes in leakage rates are detected in proportionally shorter times.

Condensate from the eight drywell unit coolers is routed to the drywell floor drain sump and is monitored by a series of flow transmitters that provide indication and alarms in the main control room. The outputs from the flow transmitters are added together by summing units to provide a total continuous condensate drain flow rate. The high flow alarm setpoint is based on condensate drain flow rate in excess of 1 gpm over the currently identified preset leak rate. The drywell unit cooler condensate flow rate monitoring system serves as an added indicator, but not quantifier, of RCS unidentified leakage.

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 4 of 8 Docket No. 50-353 Evaluation of Proposed Changes The drywell temperature and pressure monitoring systems provide an indirect method for detecting RCPB leakage. A temperature and/or pressure rise in the drywell above normal levels may be indicative of reactor coolant or steam leakage.

4.0 TECHNICAL ANALYSIS

Proposed LGS TS LCO 3.4.3.1, new Action F.

Limerick has four (4) individual RCS leakage detection systems required by TS LCO 3.4.3.1. Currently, the drywell unit cooler condensate flow rate monitoring system is inoperable and cannot be repaired without a unit shutdown. Proposed TS LCO 3.4.3.1, Action F, requires that, with the drywell unit cooler condensate flow rate monitoring system inoperable and one other RCS leakage detection system inoperable, other than the primary containment atmosphere gaseous radioactivity monitoring system (existing TS Action E), at least one of the leakage detection systems be restored to operable status within 7 days and that a Channel Check of the primary containment atmosphere gaseous radioactivity monitoring system (SR 4.4.3.1.a) be performed once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. It is recognized that with two RCS leakage detection systems inoperable, the diversity of the means for detecting RCS leakage is reduced. However, the 7-day allowed outage time recognizes that other forms of RCS leakage detection are available and ensures that the plant will not be operated in this degraded configuration for an extended period of time. As discussed in the Bases to LGS TS 3.4.3.1, the drywell floor drain sump flow monitoring system, the primary containment atmosphere gaseous radioactivity monitoring system and the drywell unit coolers condensate flow rate monitoring system all have the capability of detecting a change in leakage at a rate of 1 gpm within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in conformance with Regulatory Guide (RG) 1.45 (Reference 1) while the primary containment pressure and temperature monitoring system provides an indirect method for detecting RCPB leakage. Relative to proposed TS LCO 3.4.3.1, Action F, as indicated in the table below, with the drywell unit cooler condensate flow rate monitoring system inoperable and one other RCS leakage detection system inoperable, the combination of RCS leakage detection systems that remain operable will always involve at least one RCS leakage detection system that has the capability of detecting a change in leakage at a rate of 1 gpm within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. In some situations, there may be two remaining operable RCS leakage detections systems that have this capability.

The following table summarizes the inoperable combination of RCS leakage detection systems and the supplementary Action associated with the new proposed Action F.

INOPERABLE OPERABLE ACTION F - SUPPLEMENTARY ACTIONS Perform a Channel Check of the primary containment atmosphere FD/UC RM/PT gaseous radioactivity monitoring system once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

Perform a Channel Check of the primary containment atmosphere UC/PT FD/RM gaseous radioactivity monitoring system once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

FD - Drywell floor drain sump flow monitoring system RM - Primary containment atmosphere gaseous radioactivity monitoring system UC - Drywell unit coolers condensate flow rate monitoring system PT - Primary containment pressure and temperature monitoring system

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 5 of 8 Docket No. 50-353 Evaluation of Proposed Changes In addition, the RCS leakage detection systems at LGS consist of one (1) system to quantify leakage (drywell floor drain sump flow monitoring), three (3) early detection systems (drywell floor drain sump flow monitoring, primary containment atmosphere gaseous radioactivity monitoring, and drywell unit cooler condensate flow rate monitoring) and one (1) indirect leakage detection method (containment press and temperature). The current TS LCO 3.4.3.1 specifies an Action for each inoperable RCS leakage detection system. The proposed TS LCO 3.4.3.1, Action F will allow the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system to be inoperable; however, the two remaining operable RCS leakage detection systems would consist of at least one (1) early detection system. For example, the proposed TS LCO 3.4.3.1, Action F will allow the drywell unit cooler condensate flow rate monitoring system (an early detection system) and the drywell floor drain sump flow monitoring system (which is also an early detection system) to be inoperable. In this case, the remaining operable RCS leakage detection systems would consist of one (1) early detection system (the primary containment atmosphere gaseous radioactivity monitoring system) and the indirect leakage detection monitor (primary containment pressure and temperature monitoring system).

As indicated in the table above, proposed TS LCO 3.4.3.1, Action F also includes a supplementary Action. With the drywell unit cooler condensate flow rate monitoring system inoperable, and either the drywell floor drain sump flow monitoring system or the primary containment pressure and temperature monitoring system inoperable, then Action F requires that a Channel Check of the primary containment atmosphere gaseous radioactivity monitoring system be performed once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> rather than once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The increased frequency for performing this supplementary Action makes up for the loss of the inoperable RCS leakage detection systems. In addition, the frequency of performing the supplementary Action provides periodic information that is adequate to detect RCS leakage. This supplementary Action is consistent with the supplementary Action described in TS LCO 3.4.3.1, Action C for an inoperable drywell unit cooler condensate flow rate monitoring system and an operable primary containment atmosphere gaseous radioactivity monitoring system.

In addition, as discussed in the Bases for TS LCO 3.4.3.1, although not credited for operability of the drywell floor drain sump flow monitoring system, the discharge of each sump is monitored by an independent flow element. The measured flow rate from the flow element is integrated and recorded. A main control room alarm is provided to indicate an excessive sump discharge measured via the flow element. This flow measurement is not continuous but is measured on a periodic basis when the sump is drained. Regardless, if the drywell floor drain sump flow monitoring system is inoperable in addition to the drywell unit cooler condensate flow rate monitoring system, this provides an alternative indication of RCS leakage.

Proposed LGS TS LCO 3.4.3.1, new Action G (revised old Action F)

Existing TS LCO 3.4.3.1, Action E and proposed new Action F provide Action requirements that cover all combinations of the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system being inoperable. As a result, the new Action G, i.e., the old Action F, is revised to address the condition of any

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 6 of 8 Docket No. 50-353 Evaluation of Proposed Changes two or more RCS leakage detection systems, other than those specified in TS Actions E or F, being inoperable. Under this condition, the number and diversity of leakage detection systems has degraded to the point that the plant must be brought to an operational condition in which the TS LCO does not apply. Also, if any of the required Actions individually cannot be met in the allotted time period, the plant must be brought to an operational condition in which the TS LCO does not apply. In this case, the plant must be brought to Hot Shutdown in 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and Cold Shutdown within the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

5.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration Exelon has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, Issuance of amendment, as discussed below:

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

Response: No. The proposed changes continue to maintain an acceptable level of reactor coolant system (RCS) leakage detection instrumentation required to support plant operations. The level of RCS leakage detection capability inherent with the proposed changes will continue to provide acceptable early warning detection of potential RCS pressure boundary degradation. The proposed changes do not impact the physical configuration or design function of plant structures, systems, or components (SSCs) or the manner in which SSCs are operated, modified, tested, or inspected. The proposed changes do not impact the initiators or assumptions of analyzed events, nor do they impact mitigation of accidents or transient events. Therefore, the proposed changes do not involve a significant increase in the probability or consequences of an accident previously evaluated.

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

Response: No. The proposed changes only affect systems associated with the detection of leakage resulting from the degradation of the RCS pressure boundary. The proposed changes do not alter plant configuration or require that new plant equipment be installed. The RCS leakage detection systems will continue to function as designed in all modes of operation. No new accident type is created as a result of the proposed changes. No new failure mode for any equipment is created. The proposed changes do not alter assumptions made about accidents previously evaluated. Therefore, the proposed changes do not create the possibility of a new or different kind of accident from any accident previously evaluated.

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 7 of 8 Docket No. 50-353 Evaluation of Proposed Changes

3. Do the proposed changes involve a significant reduction in a margin of safety?

Response: No. The proposed changes do not involve any physical changes to plant SSCs or the manner in which SSCs are operated, modified, tested, or inspected. The proposed changes do not involve a change to any safety limits, limiting safety system settings, limiting conditions of operation, or design parameters for any SSC. The proposed changes do not impact any safety analysis assumptions and do not involve a change in initial conditions, system response times, or other parameters affecting an accident analysis. Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

Based on the above, Exelon concludes that the proposed amendment presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

5.2 Applicable Regulatory Requirements/Criteria General Design Criterion 30, "Quality of Reactor Coolant Pressure Boundary," of Appendix A to 10 CFR Part 50, "General Design Criteria for Nuclear Power Plants,"

(Reference 2) requires that means be provided for detecting and, to the extent practical, identifying the location of the source of reactor coolant leakage. Regulatory Guide (RG) 1.45, "Reactor Coolant Pressure Boundary Leakage Detection Systems," describes acceptable methods of implementing this requirement with regard to the selection of leakage detection systems for the reactor coolant pressure boundary.

RG 1.45 specifies that at least three separate detection methods should be employed.

Two of the methods should be sump level/flow monitoring and airborne radioactivity monitoring. The third method may be unit cooler condensate flow rate monitoring. In addition, RG 1.45 suggests that temperature or pressure monitoring of the containment atmosphere be considered as indirect indication of leakage to the containment. At LGS, leakage from the RCPB inside the drywell is detected by at least one of four (4) independently monitored variables which include drywell drain sump level changes over time yielding drain flow rates, and drywell gaseous radioactivity, drywell unit cooler condensate flow rate and drywell pressure/temperature levels. The proposed changes do not alter plant configuration. The RCS leakage detection systems will continue to function as designed in all modes of operation. The proposed changes allow the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system to be inoperable at one time; however, because of the number and diversity of leakage detection systems, there remains sufficient instrumentation to provide early detection of RCS leakage.

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 Commissions 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.

License Amendment Request Attachment 1 One-Time Changes to TS SR 3.4.3.1 (RCS Leakage Detection Systems) Page 8 of 8 Docket No. 50-353 Evaluation of Proposed Changes

6.0 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 10 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 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

7.0 REFERENCES

1. Regulatory Guide 1.45, Reactor Coolant Pressure Boundary Leakage Detection Systems, " dated May 1973.

2. 10 CFR 50, Appendix A, General Design Criterion 30, "Quality of Reactor Coolant Pressure Boundary."

ATTACHMENT 2 License Amendment Request Limerick Generating Station, Unit 2 Docket No. 50-353 Proposed One-Time Changes to Technical Specifications Section 3.4.3.1 -

Reactor Coolant System Leakage Detection Systems Markup of Proposed Technical Specifications Page Unit 2 TS Page 3/4 4-8a

ACTOR COOLANT SYSTEM EONS ( C o n t i n u e d )

s W i t h any two o r m o r e m e c t i o n systems i n o p e r a b l e o t h e r than-above.0R w i t h reaui red Actio a s s o c i a t e d C o m p l e t i o n Time o f ACTIONS , B ,

i n HOT SHUTDOWN w i t h i n 12 h o u r s AND i n COLD SHUTDOWN-within 3.3.1 The r e a c t o r c o o l a n t system l e a k a g e d e t e c t i o n systems s h a l l be d e m o n s t r a t e d 2rable by:

a. P e r f o r m a CHANNEL CHECK o f t h e p r i m a r y c o n t a i n m e n t atmosphere gaseous r a d i o a c t i v i t y moni t o r i n g system i n accordance w i t h t h e S u r v e i 11 ance Frequency C o n t r o l Program.

b. P e r f o r m a CHANNEL FUNCTIONAL TEST o r r e q u i r e d l e a k a g e d e t e c t i o n i n s t r u m e n t a t i o n i n accordance w i t h t h e S u r v e i l 1 ance Frequency C o n t r o l Program. T h i s does n o t a p p l y t o c o n t a i n m e n t p r e s s u r e and t e m p e r a t u r e m o n i t o r i n g system.

C. P e r f o r m a CHANNEL CALIBRATION o f r e q u i r e d l e a k a g e d e t e c t i o n i n s t r u m e n t a t i o n i n accordance w i t h t h e S u r v e i l l a n c e Frequency C o n t r o l Program. T h i s does n o t a p p l y t o c o n t a i n m e n t p r e s s u r e and t e m p e r a t u r e m o n i t o r i n g system.

d. M o n i t o r p r i m a r y c o n t a i n m e n t p r e s s u r e AND p r i m a r y c o n t a i n m e n t t e m p e r a t u r e i n accordance w i t h t h e S u r v e i 11 ance Frequency C o n t r o l Program.

LIMERICK - UNIT 2 3/4 4-8a Amendment No. 44.3, 1,47

TS 3.4.3.1 LCO Action Insert F. With the drywell unit cooler condensate flow rate monitoring system inoperable and one other RCS leakage detection system inoperable, other than the primary containment atmosphere gaseous radioactivity monitoring system (ACTION E), restore at least one of the leakage detection systems to OPERABLE status within 7 days AND perform a CHANNEL CHECK of the primary containment atmosphere gaseous radioactivity monitoring system (SR 4.4.3.1.a) once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.*

Footnote

• ACTION F is only effective for the remainder of the current operating cycle (Cycle 10), which is currently scheduled to end in the Spring of 2009, or until the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.

ATTACHMENT 3 License Amendment Request Limerick Generating Station, Unit 2 Docket No. 50-353 Proposed One-Time Changes to Technical Specifications Section 3.4.3.1 -

Reactor Coolant System Leakage Detection Systems Markup of Proposed Technical Specifications Bases Page Unit 2 TS Page B 3/4 4-3c

REACTOR COOLANT SYSTEM ACTIONS ( C o n t i n u e d )

C. W i t h t h e r e q u i r e d p r i m a r y containment a i r c o o l e r condensate f l o w r a t e m o n i t o r i n g system i n o p e r a b l e , SR 4.4.3.1.a must be performed e v e r y 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> t o p r o v i d e p e r i o d i c i n f o r m a t i o n o f a c t i v i t y i n t h e p r i m a r y containment a t a more f r e q u e n t i n t e r v a l t h a n t h e r o u t i n e f r e q u e n c y o f every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> i n t e r v a l p r o v i d e s p e r i o d i c i n f o r m a t i o n t h a t i s adequate t o d e t e c t leakage and recognizes t h a t o t h e r forms o f leakage d e t e c t i o n a r e a v a i l a b l e . The r e q u i r e d ACTION has been c l a r i f i e d t o s t a t e t h a t t h e a d d i t i o n a l s u r v e i 11 ance r e q u i rement i s n o t appl i c a b l e i f t h e r e q u i r e d p r i m a r y c o n t a i n m e n t atmosphere gaseous r a d i o a c t i v i t y m o n i t o r i n g system i s a l s o i n o p e r a b l e . C o n s i s t e n t w i t h SR 4.0.3, s u r v e i l l a n c e s a r e n o t r e q u i r e d t o be performed on i n o p e r a b l e equipment. I n t h i s case, ACTION Statement A. and E. requirements apply

0. W i t h t h e p r i m a r y containment p r e s s u r e and temperature m o n i t o r i n g system i n o p e r a b l e ,

o p e r a t i o n may c o n t i n u e f o r up t o 30 days g i v e n t h e systems i n d i r e c t c a p a b i l i t y t o d e t e c t RCS leakage. However, o t h e r more l i m i t i n g Tech Spec requirements a s s o c i a t e d w i t h t h e p r i m a r y containment pressure/temperature m o n i t o r i n g system w i l l s t i l l apply E . With b o t h t h e p r i m a r y containment atmosphere gaseous r a d i o a c t i v i t y m o n i t o r and t h e p r i m a r y c o n t a i n m e n t a i r c o o l e r condensate f l o w r a t e m o n i t o r i n o p e r a b l e , t h e o n l y means o f d e t e c t i n g leakage i s t h e d r y w e l l f l o o r d r a i n sump m o n i t o r and t h e d r y w e l l pressure/ternperature i n s t r u m e n t a t i o n . T h i s c o n d i t i o n does n o t p r o v i d e t h e r e q u i r e d d i v e r s e means o f leakage d e t e c t i o n . The r e q u i r e d ACTION i s t o r e s t o r e e i t h e r o f t h e i n o p e r a b l e m o n i t o r s t o OPERABLE s t a t u s w i t h i n 30 days t o r e g a i n t h e i n t e n d e d leakage d e t e c t i o n d i v e r s i t y . The 30 day Completion Time ensures t h a t t h e p l a n t w i l l n o t be o p e r a t e d i n a degraded c o n f i g u r a t i o n f o r a l e n g t h y t i m e p e r i o d . While t h e p r i m a r y gaseous r a d i o a c t i v i t y moni t o r is INOPERABLE, P r i m a r y q u i rements a1 so a p p l y .

p c grab samples w i l l be t a k e n and analyzed e v e r y 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> s i n c e o f C o n d i t i o n s A, B, C, D5$f E cannot be met w i t h i n t h e Time, t h e p l a n t must be b r o u g h t t o an OPERATIONAL CONDITION i n apply. To achieve t h i s s t a t u s , t h e p l a n t must be b r o u g h t t o i t h i n 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and COLD SHUTDOWN w i t h i n t h e n e x t 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Times a r e reasonable, based on o p e r a t i n g experience, t o an o r d e r l y manner and w i t h o u t c h a l l engi ng p l a n t systems.

SURVEILLANCE REQUIREMENTS SR 4.4.3.1.a T h i s SR i s f o r t h e performance o f a CHANNEL CHECK o f t h e r e q u i r e d p r i m a r y containment atmospheric m o n i t o r i n g system. The check g i v e s reasonable c o n f i d e n c e t h a t t h e channel i s operating properly.

I LIMERICK - U N I T 2 B 3/4 4 - 3 c Amendment U,4 2 2 , 1 4 7

TS 3.4.3.1 Bases Inserts F. With the drywell unit cooler condensate flow rate monitoring system and one other RCS leakage detection system inoperable, other than the primary containment atmosphere gaseous radioactivity monitoring system as described in ACTION E, the required ACTION is to restore either of the inoperable monitors to OPERABLE status within 7 days and to perform a CHANNEL CHECK of the primary containment atmosphere gaseous radioactivity monitoring system once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 7-day Completion Time is based on the possibility that the other inoperable leakage detection system is the drywell floor drain sump flow monitoring system, which is the primary method for quantifying RCS leakage. The 7-day Completion Time ensures that the plant will not be operated in a degraded configuration for an extended time period. The following table summarizes the inoperable combination of RCS leakage detection systems and the supplementary Action associated with ACTION F*.

INOPERABLE OPERABLE ACTION F - SUPPLEMENTARY ACTIONS FD/UC RM/PT Perform a Channel Check of the primary containment atmosphere gaseous radioactivity monitoring system once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

UC/PT FD/RM Perform a Channel Check of the primary containment atmosphere gaseous radioactivity monitoring system once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

FD - Drywell floor drain sump flow monitoring system RM - Primary containment atmosphere gaseous radioactivity monitoring system UC - Drywell unit coolers condensate flow rate monitoring system PT - Primary containment pressure and temperature monitoring system The increased frequency for performing this supplementary Action makes up for the loss of the inoperable RCS leakage detection systems. In addition, the frequency of performing the supplementary Action provides periodic information that is adequate to detect RCS leakage.

This supplementary Action is consistent with the supplementary Action described in TS LCO 3.4.3.1, Action C. for an inoperable drywell unit cooler condensate flow rate monitoring system and an operable primary containment atmosphere gaseous radioactivity monitoring system.

G. With any two or more leakage detection systems inoperable, other than those specified in Actions E or F*, the number and diversity of leakage detection systems is degraded to the point that the plant must be brought to an OPERATIONAL CONDITION in which the LCO does not apply.

Footnote

• ACTION F is only effective for the remainder of the current operating cycle (Cycle 10), which is currently scheduled to end in the Spring of 2009, or until the next shutdown of sufficient duration to allow for drywell unit cooler condensate flow rate monitoring system repairs, whichever comes first.