SVP-99-038, Application for Amends to Licenses DPR-29 & DPR-30,allowing Alternate Methodology for Quantifying RCS Leakage When Normal RCS Leakage Detection Sys Is Inoperable

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Application for Amends to Licenses DPR-29 & DPR-30,allowing Alternate Methodology for Quantifying RCS Leakage When Normal RCS Leakage Detection Sys Is Inoperable
ML20205J987
Person / Time
Site: Quad Cities  Constellation icon.png
Issue date: 03/30/1999
From: Dimmette J
COMMONWEALTH EDISON CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20205J990 List:
References
SVP-99-038, SVP-99-38, NUDOCS 9904120284
Download: ML20205J987 (8)
v • d • e


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( .ordon a. !!. 612 e2 *)740 Tri w>v,u2 ii SVP-99-038 March 30,1999 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D C 20555 Quad Citics Nuclear Power Station, Unit I and Unit 2 FacEity Operating License Nos. DPR-29 and DPR-30 NRC Docket Nos. 50-254 and 50-265

Subject:

Technical Specification Change Request Technical Specification Section 3/4.6.G, Leakage Detection Systems

Reference:

Letter from L. Olshan (USNRC) to T. Kovach (Comed), dated August 21,1990," Review of Response to Generic Letter 88-01, NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping" Pursuant to 10 CFR 50.90, Commonwealth Edison (Comed) Company proposes to change Appendix A, Technical Specifications (TS) Section 3/4.6.0," Leakage Detection Systems,"

of Facility Operating License., DPR-29 and DPR-30. The purpose of this proposed change is to allow an alternate methodology for quantifying Reactor Coolant System (RCS) leakage when the normal RCS leakage detection system is inoperable. This change is consistent with the NRC guidance provided in the referenced letter.

The proposed amendment request is subdivided as follows:

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1. Attachment A gives a description and safety analysis of the proposed changes,
2. Attachment B includes the marked-up Technical Specifications pages with the  ;

requested change, indicated,

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3. Attachment C provides information supporting a finding of no significant hazards in accordance with 10 CFR 50.92(c) and, t
4. Attachment D provides information supporting an environmental assessment.

9904120284 990330 }

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'USNRC 2 March 30,1999 SVP-90 438 Comed requests NRC approval of this request by October 28,1999, to be effective no later than 60 days following approval.

1 This proposed Technical Specification amendment has been reviewed and approved by j l

the On-Site Plant Operations Review Committee and Off-Site Nuclear Safety Review Board in accordance with Comed procedures.

Comed is notifying the State of Illinois of this application for amendment by transmitting a copy of this letter and its attachments to the designated State Official.

l l If there are any questions or comments concerning this letter, please refer them to Mr. Wally Beck, Acting Regulatory Assurance Manager, at (309) 654-2241, extension 3100.

Sine ely,

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l Joel P. Dimmette, Jr.

l Site Vice President  :

Quad Cities Nuclear Power Station

Attachments
A. Description and Safety Analysis for Proposed Changes l B. Marked-Up Technical Specifications Pages C. Information Supporting a Finding of No Significant Hazards D. Information Supporting an Environmental Assessment i

l cc: Regional Administrator-NRC Region III NRC Senior Resident Inspector- Quad Cities Nuclear Power S;ation l

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STATE OF ILLINOIS l Docket Nos. 50-254 50-265 IN TIIE MATTER OF COMMONWEALTII EDISON COMPANY 1

QUAD CITIES NUCLEAR POWER STATION - UNITS 1 AND 2 CII ANGE TO TECIINICAL SPECIFICATIONS SECTION 3/4.6 G, LEAKAGE DETECTION SYSTEMS AFFIDAVIT I affirm that the content of this tr smittal is true and correct to the best of my knowledge, information and belief. ,

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Site ice President Subscribed and sworn to before me, a Notary Public in and for the State above named, this 30 day of ihnacH ,19 Pi .

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Notary Public F WFICLAl N pL.EESTOERMER NatsyPdtc.M fnW2000 mem i

ATTACHMENT A l Description and Safety Analysis for Proposed Changes SVP-99-038 (Page 1 of 5) l HACKGROUND INFORMATION  !

l General Design Criteria (GDC) 30 of Appendix A to 10 CFR 50 requires a mear.s for detecting and identifying the source of any potential Reactor Coolant System (RCS)leabge. Leakage detection systems must have the capability to detect RCS boundary degradation as soon as practical to minimize the potential for propagation into a gross failure condition.

The Technical Specifications (TS) provide limits on leakage from the RCS coolant boundary so that appropriate actions can be taken before the integrity of the RCS boundary is seriously impaired. As described in Updated Final Safety Analysis Report (UFSAR) Sections 9.3.3.1 and 9.3.3.2, Quad Cities Nuclear Power Station, Unit I and Unit 2, have both a Drywell Equipment Drain Sump (DWEDS) and a Drywell Floor Drain Sump (DWFDS) which collect RCS leakage inside primary containment. The associated indication and controls for these pumps, including a  ;

flow totalizer, are located in the main control room. Using the totalizer, flow from the DWEDS i is measured every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> per TS Surveillance Requirement (SR) 4.6.H to determine IDENTIFIED system leakage. Total flow from the DWFDS is measured in a similar manner to determine UNIDENTIFIED leakage from the RCS boundary.

TS Scaion 3.6.G, Action 2, requires that with the DWFDS system inoperable in operational 1 mod 2 and 3, the system must be restored to an operable condition in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, otherwise the !

unit m. be shutdown. Historically, Quad Cities Nuclear Power Station, Unit I and Unit 2, has declazed the DWFDS system inoperable when the associated flow itotalizer (monitoring system) is not available. This is unnecessarily restrictive because alternative means are available for quantifying RCS leakage when the DWFDS monitoring system is inoperable.

A.

SUMMARY

OF PROPOSED CHANGES Pursuant to 10 CFR 50.90, Commonwealth Eo. on (Comed) Company proposes to change Appendix A, TS Section 3/4.6.G, " Leakage Detection Systems," for Facility Operating Licenses DPR-29 and DPR-30. The purpose of this proposed change is to allow an alternate methodology for quantifying RCS leakage when the DWFDS monitoring system is inoperable.

The purpose of this amendment request is to provide additional flexibility for monitoring RCS leakage and provide certain administrative changes to be consistent with the Improved Standard

Technical Specifications, NUREG-1433, Rev.1. This enhancement would allow the use of other viable means of quantifying RCS leakage. The alternative method for quantifying RCS leakage will be administratively controlled and will have a measurement sensitivity consistent with the j sump flow totalizers.

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ATTACIIMENT A Description and Safety Analysis for Proposed Changes 1

SVP-99-038

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(Page 2 of 5) l l

B. DESCRIPTION OF TIIE CURRENT REQUIREMENTS i 1

TS Section 3.6.G, Action 2, states:

With the drywellfloor drain sump system inoperable, restore the drywellfloor drain sump system to OPERABLE status within 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />s: otherwise, be in at least HOT SHUTDOWN within the next 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 thefollowing 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3.6.G, Action 2,is required to be entered whenever Limiting Condition for Operation (LCO) 3.6.G.2 is not met. LCO 3.6.G.2 requires the drywell floor drain sump system to be OPERABLE in MODE (s) 1,2, and 3.

C. BASES FOR TIIE CURRENT REQUIREMENTS The RCS leakage detection system is provided to monitor and detect leakage from the RCS pressure boundary. Limits on leakage from the RCS boundary are required so that appropriate action can be taken before the integrity of the reactor coolant pressure boundary is impaired. '

Leakage detection systems for the RCS are provided to alert the operators when leakage rates above the normal background levels are detected and also to supply quantitative measurement of leakage rates. Leakage from the RCS boundary inside the drywell is detected by two independently monitored variables: (1) sump level changes and, (2) drywell atmosphere radioactivity levels. The means of detection are required to be OPERABLE in MODE (s) 1,2, and 3. The means of quantifying leakage in the drywell is the measurement of flow from the DWFDS and DWEDS pumps.

D. NEED FOR REVISION OF TIIE REQUIREMENT j The proposed.TS amendment for Quad Cities Station, Units 1 and 2, would allow the use of other means of quantifying RCS leakage (for up to 30 days) should the DWFDS monitoring system become inoperable. Requiring the DWFDS monitoring system to be returned to an operable condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is unnecessarily restrictive because an alternate method of l quantifying RCS leakage is available (as described in Section F below).

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ATTACHMENT A Description and Safe.,5 Analysis for Proposed Chang <rc

a VP-99-038 i

(Page 3 of 5)

E. DESCRIPTION OF THE PROPOSED CIIANGES Current Requirement TS Section 3.6.G, Action 2, states:

\Vith the drywellpoor drain sump system inoperable, restore the drywellpoor drain sump system to OPERABLE status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; otherwise, be in at least HOT

' SHUTDO\YN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDO1VN within thefollowing 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

Proposed Requirement TS Section 3.6.G, Action 2, states:

\Yith the drywellpoor drain sump monitoring system inoperable, within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> establish an alternate method ofdetermining drywellfloor drain sumpjlow rates, AND withi.s 30 days restore the drywellfloor drain sump monitoring system to an OPERABLE status; otherwise, be in at least HOTSHUTDO1VN within the next 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 thefollowing 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

In order to maintain consistency with the nomenclature in the Improved Standard Technical Specifications, NUREG 1433, Rev.1, the following additional administrative changes are proposed:

l l Current LCO 3.6.G.2:

The drywellpoor drain sump system.

- Proposed LCO 3.6.G.2:

The drywellpoor drain sump monitoring system.  !

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ATTACHMENT A )

Description and Safety Analysis for Proposed Changes i l SVP 99-038 (Page 4 of 5) l l

Current Surveillance Requirements (SR) 4.6.G.2: l l

Perfonning a CHANNEL CALIBRATION of the drywellfloor '

drain sump pump dischargeflow totali er at least once per 18 months.

Proposed SR 4.6.G.2 Performing a CHANNEL CALIBRATION ofrequired leakage detection instrumentation at least once per 18 months. l t

)

The bases for TS Section 3/4.6.G will be changed to read as follows:

The RCS leakage detection systems required by this specification are provided to monitor and detect leakagefrom the reactor coolant pressure boundary. Limits on leakagefrom the reactor coolant pressure boundary are required so that appropriate action can be taken before the integrity of the reactor coolant pressure boundary is impaired. Leakage detection systemsfor the reactor coolant system are provided to alert the operators when leakage rates above the nonnal background levels are detected and also to i supply quantitative measurement ofleakage rates. Leakagefrom l the reactor coolant pressure boundary inside the drywell is detected by at least one or two independently monitored variables, such as sump level changes and drywell atmosphere radioactivity levels. The means ofquantifying leakage in the drywell is the drywellfloor drain sump pumps. With the drywellJloor drain l sump monitoring system inoperable an alternative method, such i as measuring sump run-timesfor quantifying leakage may be employedfor up to 30 days under administrative controls.

Primary containment atmosphere samplingfor radioactivity can provide indication ofchanges in leakage rates.

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l ATTACHMENT A Description and Safety Analysis for Proposed Changes l SVP-99-038 l

(Page 5 of 5)

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F. SAFETY ANALYSIS OF THE PROPOSED CHANGES The normal method for determining RCS leakage rates is to use the DWEDS and DWFDS flow totalizers. These measurements are taken once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> in accordance with TS SR 4.6.H.

The TS implies that if the flow totalizer fails, there is no alternative method for determining flow from the DWEDS and DWFDS. However, calculating flow rates using sump pump run times is an altemative method for quantifying RSC leakage. Both the DWEDS and DWFDS trip on low sump level; thus, pump run time multiplied by the rated pump flow can be used to determine the total volume of water collected in the sump between surveillances. The rated pump flow will be determined on a periodic frequency (approximately once per week) when the flow totalizer l is operable by dividing the totalizer flow by the pump run time during a routine RCS leakage surveillance. Since the totalizer will be used to determine rated pump flow, the alternate method has a measurement sensitivity consistent with the totalizer (i.e., normal method). This alternate methodology will be allowed for 30 days while effons are being made to restore the normal RCS leakage monitoring system to an operable condition. A thirty 30-day allowance is acceptable because significant degradation in rated pump flow is not expected to occur during this time frame.

In order to demonstrate the acceptability of the proposed alternate method for determining RCS l leakage, both DWEDS and DWFDS run-times have been collected (approximately once per week) since October of 1998. Using this information, Quad Cities Nuclear Power Station, Unit I and Unit 2, has been able to compare calculated rated pump flow to totalizer volume for both the DWEDS and DWFDS. An examination of this information has indicated no significant degradation in pump performance and comparison of calculated to measured mies are consistent.

For this reason, the alternate method of calculating RCS leakage is acceptable during the proposed 30-day allowed outage time for the normal floor drain sump monitoring system..

The alternate methodology will be controlled by station procedures and mflected in the UFSAR.

In addition, the altemate method is consistent with NRC guidance provided in letter L. Olshan (USNRC) to T. Kovach (Comed) dated August 21,1990, concerning Generic Letter 88-01, "NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping."

G. IMPACT ON PREVIOUS SUBMITTALS Comed has reviewed previous sthnittals and has concluded the proposed change has no impact on previous submittals currently under NRC review.

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! IL SCHEDULE REQUIREMENTS Comed requests NRC approval of this request by October 28,1999, to be effective no later than 60 days following approval.

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