ML110960216

LaSalle, Units 1 & 2, License Amendment Request for Adoption of Technical Specifications Task Force (TSTF) Traveler TSTF-514, Revision 3, Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation.

ML110960216
Person / Time
Site:	LaSalle
Issue date:	04/04/2011
From:	Hansen J L Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-11-036
Download: ML110960216 (24)

Text

n Nuclear RS-11-036 April 4, 2011 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 10 CFR 50.90

Subject:

License Amendment Request for Adoption of Technical Specifications Task Force (TSTF) Traveler TSTF-514, Revision 3, "Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation" In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Exelon Generation Company, LLC (EGC) is submitting a request for an amendment to the Technical Specifications (TS) of Facility Operating License Nos. NPF-11 and NPF-18 for LaSalle County Station, Units 1 and 2 (LSCS). The proposed amendment would revise the TS to define a new time limit for restoring inoperable Reactor Coolant System (RCS) leakage detection instrumentation to operable status; establish alternate methods of monitoring RCS leakage when one or more required monitors are inoperable; and make TS Bases changes which reflect the proposed changes and more accurately reflect the contents of the facility design basis related to operability of the RCS leakage detection instrumentation.

These changes are consistent with NRC-approved Revision 3 to TSTF Improved Standard Technical Specification (STS) Change Traveler TSTF-514, "Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation." The availability of this TS improvement was announced in the Federal Register on December 17, 2010, (75 FR 79048) as part of the consolidated line item improvement process (CUIP).

• Attachment 1 provides an evaluation of the proposed changes.

• Attachment 2 provides the markup pages of existing TS to show the proposed changes.

• Attachment 3 provides the markup pages of the existing TS Bases to show the proposed changes.

• Attachment 4 provides revised (clean) TS pages. EGC requests approval of the proposed license amendment by April 4, 2012, with the amendment being implemented within 60 days.

U. S. Nuclear Regulatory Commission April 4, 2011 Page 2 In accordance with 10 CFR 50.91(a)(1), "Notice for Public Comment," the analysis about the issue of no significant hazards consideration using the standards in 10 CFR 50.92 is being provided to the NRC. The proposed amendment has been reviewed by the LSCS Plant Operations Review Committee and approved by the Nuclear Safety Review Board in accordance with the requirements of the EGC Quality Assurance Program. EGC is notifying the State of Illinois of this application for a change to the TS by sending a copy of this letter and its attachments to the designated State Official in accordance with 10 CFR 50.91, "Notice for public comment; State consultation," paragraph (b). There are no regulatory commitments contained within this letter. Should you have any questions concerning this letter, please contact Mitchel Mathews at (630) 657-2819.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 4th day of April 2011. Attachment 1: Attachment 2: Attachment 3: Attachment 4: Evaluation of Proposed Changes Markup pages of existing TS to show the proposed changes. Markup pages of existing TS Bases to show the proposed changes. Clean TS Pages cc: Illinois Emergency Management Agency -Division of Nuclear Safety ATTACHMENT 1 Evaluation of Proposed Changes

Subject:

License Amendment Request for Adoption of TSTF-514, Revision 3, "Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation"

1.0 DESCRIPTION

2.0 PROPOSED

CHANGES 3.0 BACKGROUND

4.0 TECHNICAL

ANALYSIS 5.0 REGULATORY SAFETY ANALYSIS 5.1 No Significant Hazards Consideration Determination

5.2 Applicable

Regulatory ReqUirements/Criteria

6.0 ENVIRONMENTAL

CONSIDERATION

7.0 REFERENCES

Page 1 of 7

1.0 DESCRIPTION

ATTACHMENT 1 Evaluation of Proposed Changes The proposed amendment would revise the Technical Specifications (TS) to define a new time limit for restoring inoperable Reactor Coolant System (RCS) leakage detection instrumentation to operable status; establish alternate methods of monitoring RCS leakage when one or more required monitors are inoperable and make conforming TS Bases changes. These changes are consistent with NRC-approved Revision 3 to Technical Specification Task Force (TSTF) Standard Technical Specification (STS) Change Traveler TSTF-514, "Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation." The availability of this TS improvement was announced in the Federal Register on December 17,2010 (75 FR 79048) as part of the consolidated line item improvement process (CUIP). 2.0 PROPOSED CHANGES The proposed changes revise and add a new Condition D to TS 3.4.7, "RCS Leakage Detection Instrumentation," and revise the associated bases. New Condition D is applicable when the drywell atmospheric gaseous radiation monitor is the only operable TS-required instrument monitoring RCS leakage, i.e., TS-required particulate, sump, and drywell air cooler condensate flow monitors are inoperable.

New Condition D Required Actions require monitoring RCS leakage by obtaining and analyzing grab samples of the drywell atmosphere every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />; monitoring RCS leakage using administrative means every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />; and taking action to restore monitoring capability using another monitor within 7 days. Additionally, the TS Bases, which summarize the reasons for the specifications, are revised to clarify the specified safety function for each required instrument in Limiting Condition for Operation (LCO) Bases, delete discussion from the TS Bases that could be construed to alter the meaning of TS operability requirements, and reflect the changes made to TS 3.4.7. Exelon Generation Company, LLC (EGC) is not proposing variations or deviations from the TS changes described in TSTF-514, Revision 3, or the NRC staffs model safety evaluation (SE) published in the Federal Register on December 17, 2010 (75 FR 79048) as part of the CUIP Notice of Availability.

3.0 BACKGROUND

NRC Information Notice (IN) 2005-24, "Nonconservatism in Leakage Detection Sensitivity," dated August 3,2005, informed addressees that the reactor coolant activity assumptions for primary containment atmospheric gaseous radioactivity monitors may be non-conservative.

This means the monitors may not be able to detect a one gallon per minute leak within one hour. Some licensees, in response to IN 2005-24, have taken action to remove the gaseous radioactivity monitor from the TS list of required monitors.

However, industry experience has shown that the primary containment atmospheric gaseous radiation monitor is often the first monitor to indicate an increase in RCS leak rate. As a result, the TSTF and the NRC staff met on April 29, 2008, and April 14, 2009, to develop an alternative approach to address the issue identified in IN 2005-24. The agreed upon solution is to retain the primary containment atmospheric gaseous radiation monitor in the LCO list of required equipment, revise the Page 2 of 6 ATTACHMENT 1 Evaluation of Proposed Changes specified safety function of the gas monitor to specify the required instrument sensitivity level, to revise the Actions requiring additional monitoring, and provide less time before a plant shutdown is required when the primary containment atmospheric gaseous radiation monitor is the only operable monitor. 4.0 TECHNICAL ANALYSIS EGC has reviewed TSTF-514, Revision 3, and the model SE published on December 17, 2010, (75 FR 79048) as part of the CLlIP Notice of Availability.

EGC has concluded that the technical bases presented in TSTF Traveler-514, Revision 3, and the model SE prepared by the NRC staff are applicable to LaSalle County Station, Units 1 and 2 (LSCS). General Design Criterion (GDC) 30, "Quality of Reactor Coolant Pressure Boundary," of Appendix A to 10 CFR Part 50, "General Design Criteria for Nuclear Power Plants," requires that means be provided for detecting and, to the extent practical, identifying the location of the source of reactor coolant leakage. An evaluation against the GDC 30 is provided in Section 3.1.2.4.1 of the LSCS UFSAR. As discussed in Appendix B of the LSCS UFSAR, LSCS is committed to NRC Regulatory Guide (RG) 1.45, "Reactor Coolant Pressure Boundary Leakage Detection Systems," Revision O. NRC RG 1.45 describes methods acceptable to the NRC to assure that leakage detection and collection systems provide maximum practical identification of leaks within the reactor coolant pressure boundary.

The LSCS RCS leakage detection systems are consistent with the recommendations of NRC RG 1.45, Revision O. The administrative means of monitoring include diverse alternative mechanisms from which appropriate indicators may be selected based on plant conditions.

As described in Section 5.2.5.2 of the LSCS Updated Final Safety Analysis Report (UFSAR), "Leak Detection Devices Within Primary Containment," EGC utilizes the following diverse methods to detect unidentified leakage at LSCS: drywell floor drain sump measurement, drywell equipment drain sump, drywell cooler drain flow, drywell pressure, drywell temperature, drywell air sampling, reactor vessel head closure seal annulus pressure, reactor water recirculation pump seal flow rate, safety/relief valve discharge piping temperature, and valve packing leakage. There are diverse alternative methods for determining that RCS leakage has not increased, from which appropriate indicators may be selected based on plant conditions.

EGC will utilize the following method or methods considering the current plant conditions and historical or expected sources of unidentified leakage: drywell floor drain sump measurement, drywell equipment drain sump, drywell cooler drain flow, drywell pressure, drywell temperature, drywell air sampling, reactor vessel head closure seal annulus pressure, reactor water recirculation pump seal flow rate, safety/relief valve discharge piping temperature, valve packing leakage, component cooling water system outlet temperatures, component cooling water system makeup, reactor recirculation system pump seal pressure and temperature, reactor recirculation system pump motor cooler temperatures, drywell cooling fan outlet temperatures, reactor building chiller amperage, and control rod drive system flange temperatures.

Actions to verify that these indications have not increased since the required monitors became inoperable and Page 3 of 6 ATTACHMENT 1 Evaluation of Proposed Changes the analysis of drywell atmospheric grab samples are sufficient to alert the operating staff to an unexpected increase in RCS leakage. 5.0 REGULATORY SAFETY ANALYSIS 5.1 No Significant Hazards Consideration Determination Exelon Generation Company, LLC (EGC) has evaluated the proposed changes to the TS using the criteria in 10 CFR 50.92 and has determined that the proposed changes do not involve a significant hazards consideration.

An analysis of the issue of no significant hazards consideration is presented below: Description of Amendment Request: The proposed amendment would revise TS 3.4.7, "RCS Leakage Detection Instrumentation," Conditions and Required Actions and the licensing basis for the drywell atmospheric gaseous radiation monitor, as well as make associated TS Bases changes for TS 3.4.7. Basis for proposed no significant hazards consideration determination:

As required by 10 CFR 50.91(a), the EGC analysis of the issue of no significant hazards consideration using the standards in 10 CFR 50.92 is presented below: 1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response:

No The proposed change clarifies the operability requirements for the RCS leakage detection instrumentation and reduces the time allowed for the plant to operate when the only required operable Reactor Coolant System (RCS) leakage detection instrumentation monitor is the drywell atmospheric gaseous radiation monitor. The monitoring of RCS leakage is not a precursor to any accident previously evaluated.

The monitoring of RCS leakage is not used to mitigate the consequences of any accident previously evaluated.

Therefore, it is concluded that this change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

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

Response:

No The proposed change clarifies the operability requirements for the RCS leakage detection instrumentation and reduces the time allowed for the plant to operate when the only required operable RCS leakage detection instrumentation monitor is the drywell atmospheric gaseous radiation monitor. The proposed change does not involve a physical alteration of the plant (Le., no new or different type of equipment will be installed) or a change in the methods governing normal plant operation.

Therefore, it is concluded that Page 4 of 6 ATTACHMENT 1 Evaluation of Proposed Changes the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety? Response:

No The proposed change clarifies the operability requirements for the RCS leakage detection instrumentation and reduces the time allowed for the plant to operate when the only required operable RCS leakage detection instrumentation monitor is the drywell atmospheric gaseous radiation monitor. Reducing the amount of time the plant is allowed to operate with only the drywell atmospheric gaseous radiation monitor operable increases the margin of safety by increasing the likelihood that an increase in RCS leakage will be detected before it potentially results in gross failure. Therefore, it is concluded that the proposed change does not involve a significant reduction in a margin of safety. Based upon the above analysis, EGC concludes that the requested change does not involve a significant hazards consideration, as set forth in 10 CFR 50.92(c), "Issuance of Amendment." 5.2 Applicable Regulatory Requirements/Criteria A description of the proposed TS change and its relationship to applicable regulatory requirements were published in the Federal Register Notice of Availability on December 17, 2010 (75 FR 79048). EGC has reviewed the NRC staffs model SE referenced in the CUIP Notice of Availability and concluded that the regulatory evaluation section is applicable to LSCS. General Design Criterion (GDC) 30, "Quality of Reactor Coolant Pressure Boundary," of Appendix A to 10 CFR Part 50, "General DeSign Criteria for Nuclear Power Plants," requires that means be provided for detecting and, to the extent practical, identifying the location of the source of reactor coolant leakage. An evaluation against the GDC 30 is provided in Section 3.1.2.4.1 of the LSCS UFSAR. As discussed in Appendix B of the LSCS UFSAR, LSCS is committed to NRC Regulatory Guide 1.45, "Reactor Coolant Pressure Boundary Leakage Detection Systems," Revision O. NRC Regulatory Guide (RG) 1.45 describes methods acceptable to the NRC to assure that leakage detection and collection systems provide maximum practical identification of leaks within the reactor coolant pressure boundary.

The LSCS RCS leakage detection systems are consistent with the recommendations of NRC RG 1.45, Revision O. Page 5 of 6 ATTACHMENT 1 Evaluation of Proposed Changes 6.0 ENVIRONMENTAL CONSIDERATION The proposed change would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR Part 20, and would change an inspection or surveillance requirement.

However, the proposed change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed change 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 change.

7.0 REFERENCES

7.1 TSTF-514 "Revise BWR Operability Requirements and Actions for RCS Leakage Instrumentation," Revision 3 7.2 U.S. Nuclear Regulatory Commission Model Safety Evaluation on the "Technical Specification Task Force (TSTF) Change TSTF-514, "Revised BWR Operability Requirements and Actions for RCS Leakage Instrumentation," dated December 7,2010 Page 6 of 6 ATTACHMENT 2 LASALLE COUNTY STATION UNITS 1 AND 2 Docket Nos. 50-373 and 50-374 License Nos. NPF-11 and NPF-18 Markup Pages of Existing Technical Specifications to Show the Proposed Changes MARKUP OF EXISTING REVISED TS PAGES 3.4.7-2 New Condition D

ACTIONS CONDITION C. Drywell air cooler condensate flow rate monitoring system inoperable.

RCS Leakage Detection Instrumentation

3.4.7 REQUI

RED ACTION ------------

NOT E -------------

Not applicable when the required drywell atmospheric monitoring system is inoperable.

C.1 Perform SR 3.4.7.1. COMPLETION TIME Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> .g. Requi red drywell .g.1 Restore required drywell atmospheric monitoring system to OPERABLE status. 30 days atmospheric monitoring system inoperable.

Drywell ai r cool er condensate flow rate monitoring system inoperable. Required Action and associated Completion Time of Condition A, ot met. All required leakage detection systems inoperable.

LaSalle 1 and 2 .g.2 1 Restore drywell air cooler condensate flow rate monitoring system to OPERABLE status. Be in MODE 3. Be in MODE 4. Enter LCO 3.0.3. 30 days 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 36 hours Immediately 3.4.7-2 Amendment No. 171/157 New Condition D

ATTACHMENT 3 LASALLE COUNTY STATION UNITS 1 AND 2 Docket Nos. 50-373 and 50-374 License Nos. NPF-11 and NPF-18 Markup Pages of Existing Technical Specifications Bases to Show the Proposed Change MARKUP OF EXISTING TS BASES PAGES B 3.4.7-1 B 3.4.7-2 B 3.4.7-3 B 3.4.7-4 B 3.4.7-5 B 3.4.7-7 RCS Leakage Detection Instrumentation B 3.4.7 B 3.4 REACTOR COOLANT SYSTEM (RCS) B 3.4.7 RCS Leakage Detection Instrumentation BASES BACKGROUND LaSalle 1 and 2 GDC 30 of 10 CFR 50, Appendix A (Ref. 1), requires means for detecting and, to the extent practical, identifying the location of the source of RCS LEAKAGE. Regulatory Guide (Ref. 2) describes acceptable methods for selecting leakage detection systems. 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 (Ref. 2). 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 rates. The Bases for LCO 3.4.5, "RCS Operational LEAKAGE," iscuss the limits on RCS LEAKAGE rates. 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. LEAKAGE from the RCPB inside the drywell is detected by at least one of three independently monitored variables, such as drywell air cooler condensate flow rate, sump flow rate, and drywell gaseous and particulate radioactivity levels. The primary means of quantifying LEAKAGE in the drywell is the drywell floor drain sump flow monitoring system. The drywell floor drain sump flow monitoring system monitors the LEAKAGE collected in the floor drain sump. This unidentified LEAKAGE consists of LEAKAGE from control rod drives, valve flanges or packings, floor drains, the closed cooling water subsystems, and drywell air cooling unit condensate drains, and any LEAKAGE not collected in the drywell equipment drain sump. The drywell floor drain sump has a weir level transmitter that supplies floor drain sump fill-up rate flow indication in the main control room. The drywell floor drain sump flow monitoring system contains an additional method of measuring drywell floor drain sump flow through the use of a magnetic flow meter. The flow meter is installed on the piping that runs parallel to the sump pump piping. When in use, the magnetic flow meter measures a (continued)

B 3.4.7-1 Revision BASES BACKGROUND (continued)

APPLICABLE SAFETY ANALYSES LaSalle 1 and 2 RCS Leakage Detection Instrumentation B 3.4.7 continuous flow in the line and will display a flow rate in the control room. The floor drain sump has level switches that start and stop the sump pumps when required.

The sump pump which is selected Lead starts on a high level in the sump. The other pump starts, and a control room alarm is annunciated, if the sump level reaches the high-high level. The pumps stop when low level is reached in the sump. A timer starts each time the first sump pump starts. A second timer starts when the pump is stopped. If the pump takes longer than a given time to pump down the sump, or if the pump starts too soon after the previous pumpdown, an alarm is sounded in the control room indicating a higher than normal sump fill-up rate. A flow monitor in the discharge line of the drywell floor drain sump pumps provides flow input to a flow totalizer, which is indicated in the control room. The magnetic flow meter indication also provides an input to the flow totalizer.

The totalizer inputs can be swapped using hand switches located in the Auxiliary Electric Equipment Room and the Reactor Building.

Both monitors cannot be used simultaneously.

The flow totalizer can be used to quantify the amount of inputs. The drywell air monitoring systems continuously monitor the drywell atmosphere for airborne particulate and gaseous radioactivity.

A sudden increase of radioactivity, which may be attributed to RCPB steam or reactor water LEAKAGE, is annunciated in the control room. The drywell atmosphere particulate and gaseous radioactivity monitoring systems are not capable of quantifying leakage rates, but are sensitive enough to indicate 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 (Ref. 3). Condensate from the drywell coolers is routed to the drywell floor drain sump and is monitored by a flow transmitter that provides indication and alarms in the control room. This drywell air cooler condensate flow rate monitoring system serves as an added indicator, but not quantifier, of RCS unidentified LEAKAGE. A threat of significant compromise to the RCPB exists if the barrier contains a crack that is large enough to propagate (continued)

B 3.4.7-2 Revision BASES APPLICABLE SAFETY ANALYSES (continued)

LCD APPLICABI LITY ACTIONS LaSalle 1 and 2 RCS Leakage Detection Instrumentation B 3.4.7 rapidly. LEAKAGE rate limits are set low enough to detect the LEAKAGE emitted from a single crack in the RCPB (Refs. 4 an i). Each of the leakage detection systeffis inside the drywell is designed with the capability of detecting LEAKAGE less than the established LEAKAGE rate liffiits and providing appropriate alarffi of excess LEAKAGE in the control rOOffi. A control room alarm allows the operators to evaluate the significance of the indicated LEAKAGE and, if necessary, shut down the reactor for further investigation and corrective action. The allowed LEAKAGE rates are well the rates predicted for critical crack sizes (Ref. *-K 5 Therefore, these actions provide adequate response before a significant break in the RCPB can occur. RCS leakage detection instrumentation satisfies Criterion 1 of 10 CFR 50.36(c)(2)(ii).

The drywell floor drain SUffiP flow ffionitoring systeffi is required to quantify the unidentified LEAKAGE froffi the RCS. Thus, for the systeffi to be considered OPERABLE, the floor drain SUffiP fillup rate ffionitor or the ffiagnetic flow ffieter portion of the systeffi ffiUSt be OPERABLE.

The other ffionitoring systeffis provide early alarffis to the operators so closer exaffiination of other detection systeffis will be ffiade to deterffiine the extent of any corrective action that ffiay be required.

With the leakage detection systeffis inoperable, ffionitoring for LEAKAGE in the RCPB is degraded.

In MODES 1, 2, and 3, leakage detection systems are required to be OPERABLE to support LCD 3.4.5. This Applicability is consistent with that for LCD 3.4.5. With the drywell floor drain sump flow monitoring system inoperable, no other form of sampling can provide the equivalent information to quantify leakage. However, the drywell atmospheric activity monitor and the drywell air cooler condensate flow rate monitor will provide indications of changes in leakage. (continued)

B 3.4.7-3 Revision 22 BASES ACTIONS (continued)

LaSalle 1 and 2 RCS Leakage Detection Instrumentation B 3.4.7 With the drywell floor drain sump flow monitoring system inoperable, but with RCS unidentified and total LEAKAGE being determined every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (SR 3.4.5.1), operation may continue for 30 days. The 30 day Completion Time of Required Action A.l is acceptable, based on operating experience, considering the multiple forms of leakage detection that are still available.

With both gaseous and particulate drywell atmospheric monitoring channels inoperable (i .e., the required drywell atmospheric monitoring system), grab samples of the drywell atmosphere shall be taken and analyzed to provide periodic leakage information.

Provided a sample is obtained and analyzed every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, the plant may continue operation since at least one other form of drywell leakage detection (i .e., air cooler condensate flow rate monitor) is available.

The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> interval provides periodic information that is adequate to detect LEAKAGE. With the required drywell air cooler condensate flow rate monitoring system inoperable, SR 3.4.7.1 is performed every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to provide periodic information of activity in the drywell at a more frequent interval than the routine Frequency of SR 3.4.7.1. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> interval provides periodic information that is adequate to detect LEAKAGE and recognizes that other forms of leakage detection are available.

However, this Required Action is modified by a Note that allows this action to be not applicable if the required drywell atmospheric monitoring system is inoperable.

Consistent with SR 3.0.1, Surveillances are not required to be performed on inoperable equipment.

Gd With both the gaseous and particulate drywell atmospheric monitor channels and the drywell air cooler condensate flow rate monitor inoperable, the only means of detecting LEAKAGE is the drywell floor drain sump flow monitor. This (continued)

B 3.4.7-4 Revision ft

BASES ACTIONS SURVEILLANCE REQUIREMENTS LaSalle 1 and 2 RCS Leakage Detection Instrumentation B 3.4.7 If any Required Action of Condition A, B, C, *r-D met within the associated Completion Time, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and to MODE 4 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions in an orderly manner and without challenging plant systems. With all required monitors inoperable, no required automatic means of monitoring LEAKAGE are available, and immediate plant shutdown in accordance with LCO 3.0.3 is required.

The Surveillances are modified by a Note to indicate that when a channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, provided the other required instrumentation (the drywell sump flow monitoring system, drywell atmospheric monitori ng channel, or the drywell ai r cool er condensate flow monitoring system, as applicable) is OPERABLE.

Upon (continued)

B 3.4.7-5 Revision .f-9.

BASES SURVEI LLANCE REQUIREMENTS REFERENCES LaSalle 1 and 2 RCS Leakage Detection Instrumentation B 3.4.7 SR 3.4.7.3 (continued) drywell. The Frequency of 24 months is a typical refueling cycle and considers channel reliability.

Operating experience has proven this Frequency is acceptable.

1. 10 CFR 50, Appendix A, GDC 30. 2. Regulatory Guide 1.45 3. 4-:-GEAP-5620, "Failure Behavior in ASTM A106B Pipes Containing Axial Through-Wall Flaws," April 1968. NUREG-75/067, "Investigation and Evaluation of Cracking in Austenitic Stainless Steel Piping of Boiling Water Reactor Plants," October 1975. UFSAR, Section 5.2.5.5.2.

1 6 UFSAR S t' 52511 I ..rEL.-----, . , ec Ion . . . . .

B 3.4.7-7 Revision G-

TS Bases Insert No.1 This LCO requires instruments of diverse monitoring principles to be OPERABLE to provide confidence that small amounts of unidentified LEAKAGE are detected in time to allow actions to place the plant in a safe condition, when RCS LEAKAGE indicates possible RCPB degradation.

The LCO requires three instruments to be OPERABLE.

The drywell floor drain sump monitoring system is required to quantify the unidentified LEAKAGE rate from the RCS. Thus, for the system to be considered OPERABLE, either the flow monitoring or the sump level monitoring portion of the system must be OPERABLE and capable of determining the leakage rate. The identification of an increase in unidentified LEAKAGE will be delayed by the time required for the unidentified LEAKAGE to travel to the drywell floor drain sump and it may take longer than one hour to detect a 1 gpm increase in unidentified LEAKAGE, depending on the origin and magnitude of the LEAKAGE. This sensitivity is acceptable for containment sump monitor OPERABILITY.

The reactor coolant contains radioactivity that, when released to the primary containment, can be detected by the gaseous or particulate primary containment atmospheric radioactivity monitor. Only one of the two detectors is required to be OPERABLE.

Radioactivity detection systems are included for monitoring both particulate and gaseous activities because of their sensitivities and rapid responses to RCS LEAKAGE, but have recognized limitations.

Reactor coolant radioactivity levels will be low during initial reactor startup and for a few weeks thereafter, until activated corrosion products have been formed and fission products appear from fuel element cladding contamination or cladding defects. If there are few fuel element cladding defects and low levels of activation products, it may not be possible for the gaseous or particulate primary containment atmospheric radioactivity monitors to detect a 1 gpm increase within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during normal operation.

However, the gaseous or particulate containment primary atmospheric radioactivity monitor is OPERABLE when it is capable of detecting a 1 gpm increase in unidentified LEAKAGE within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> given an RCS activity equivalent to that assumed in the design calculations for the monitors (Reference 6). An increase in humidity of the drywell atmosphere could indicate the release of water vapor to the drywell. Drywell air cooler condensate flow rate is instrumented to detect when there is an increase above the normal value by 1 gpm. The time required to detect a 1 gpm increase above the normal value varies based on environmental and system conditions and may take longer than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. This sensitivity is acceptable for drywell air cooler condensate flow rate monitor OPERABILITY.

The LCO is satisfied when monitors of diverse measurement means are available.

Thus, the drywell floor drain sump monitoring system, in combination with a gaseous or particulate primary containment atmospheric radioactivity monitor and a drywell containment air cooler condensate flow rate monitoring system, provides an acceptable minimum.

TS Bases Insert No.2 0.1. 0.2.

0.3.1. and 0.3.2 With the drywell floor drain sump monitoring system and the drywell air cooler condensate flow rate monitoring system inoperable, the only means of detecting LEAKAGE is the primary containment atmospheric gaseous radiation monitor. A Note clarifies this applicability of the Condition.

The primary containment atmospheric gaseous radiation monitor typically cannot detect a 1 gpm leak within one hour when RCS activity is low. In addition, this configuration does not provide the required diverse means of leakage detection.

Indirect methods of monitoring RCS leakage must be implemented.

Grab samples of the primary containment atmosphere must be taken and analyzed and monitoring of RCS leakage by administrative means must be performed every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to provide alternate periodic information.

Administrative means of monitoring RCS leakage include monitoring and trending parameters that may indicate an increase in RCS leakage. There are diverse alternative mechanisms from which appropriate indicators may be selected based on plant conditions.

It is not necessary to utilize all of these methods, but a method or methods should be selected considering the current plant conditions and historical or expected sources of unidentified leakage. The administrative methods are drywell floor drain sump measurement, drywel/ equipment drain sump, drywell cooler drain flow, drywell pressure, drywell temperature, drywell air sampling, reactor vessel head closure seal annulus pressure, reactor water recirculation pump seal flow rate, safety/relief valve discharge piping temperature, valve packing leakage, component cooling water system outlet temperatures, component cooling water system makeup, reactor recirculation system pump seal pressure and temperature, reactor recirculation system pump motor cooler temperatures, drywell cooling fan outlet temperatures, reactor building chiller amperage, and control rod drive system flange temperatures.

These indications, coupled with the atmospheric grab samples, are sufficient to alert the operating staff to an unexpected increase in unidentified LEAKAGE. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> interval is sufficient to detect increasing RCS leakage. The Required Action provides 7 days to restore another RCS leakage monitor to OPERABLE status to regain the intended leakage detection diversity.

The 7 day Completion Time ensures that the plant will not be operated in a degraded configuration for a lengthy time period.

ATTACHMENT 4 LASALLE COUNTY STATION UNITS 1 AND 2 Docket Nos. 50-373 and 50-374 License Nos. NPF-11 and NPF-18 Revised Technical Specifications (Clean) Pages REVISED TS PAGES 3.4.7-2 3.4.7-3 3.4.7-4 ACTIONS CONDITION C. Drywell air cooler condensate flow rate monitoring system inoperable. ----------NOTE-----------Only applicable when the primary containment atmospheric gaseous radiation monitor is the only OPERABLE monitor. D. Drywell floor drain sump monitoring system inoperable Drywell air cooler condensate flow rate monitoring system inoperable.

LaSalle 1 and 2 RCS Leakage Detection Instrumentation 3.4.7 REQU I RED ACTI ON ------------

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

--Not applicable when the required drywell atmospheric monitoring system is inoperable.

C.1 Perform SR 3.4.7.1. 0.1 Analyze grab samples of the primary containment atmosphere.

AND 0.2 Monitor RCS LEAKAGE by administrative means. AND 0.3.1 Restore drywell floor drain sump monitoring system to OPERABLE status. OR 0.3.2 Restore drywell air cooler condensate flow rate monitoring system to OPERABLE status. COMPLETION TIME Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 7 days 7 days (continued) 3.4.7-2 Amendment No.

ACTIONS CONDITION E. Required drywell E.1 atmospheric monitoring system inoperable.

Drywell air cooler condensate flow rate monitoring system inoperable.

E.2 F. Required Action and F.1 associated Completion Time of Condition A, AND B, C, 0, or E not met. G. All required leakage detection systems inoperable.

LaSalle 1 and 2 F.2 G.1 RCS Leakage Detection Instrumentation

3.4.7 REQUIRED

ACTION Restore required drywell atmospheri c monitoring system to OPERABLE status. Restore drywell air cooler condensate flow rate monitoring system to OPERABLE status. Be in MODE 3. Be in MODE 4. Enter LCO 3.0.3. COMPLETION TIME 30 days 30 days 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 36 hours Immediately 3.4.7-3 Amendment No.

RCS Leakage Detection Instrumentation

3.4.7 SURVEILLANCE

REQUIREMENTS -------------------------------------

NOT E -------------------------------------

When a channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> provided the other required leakage detection instrumentation is OPERABLE.

SR 3.4.7.1 SR 3.4.7.2 SR 3.4.7.3 LaSalle 1 and 2 SURVEI LLANCE Perform CHANNEL CHECK of required drywell atmospheric monitoring system. Perform CHANNEL FUNCTIONAL TEST of required leakage detection instrumentation.

Perform CHANNEL CALIBRATION of required leakage detection instrumentation.

FREQUENCY In accordance with the Surveillance Frequency Control Program In accordance with the Surveillance Frequency Control Program In accordance with the Surveillance Frequency Control Program 3.4.7-4 Amendment No.