ML20210U783
| ML20210U783 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 08/04/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20210U779 | List: |
| References | |
| NUDOCS 9908200211 | |
| Download: ML20210U783 (4) | |
Text
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UNITED STATES y
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NUCLEAR REGULATORY COMMIS810N E
WAsNINGToN, D.C. segeH001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION Rpt ATED TO AA'ENDMENT NO.189 TO FACILITY OPERATING LICENSE NO. DPR-29 i
AND AMENDMENT NO.186 TO FACILITY OPERATING LICENSE NO. DPR-30 COMMONWEALTH EDISON COMPANY M
MIDAMERICAN ENERGY COMPANY QUAD CITIES NUCLEAR POWER STATION. UNITS 1 AND 2 DOCKET NOS. 50-254 AND 50-265
1.0 INTRODUCTION
i By letter dated March 30,1999, as supplemented on June 30,1999, the Commonwealth Edison Company (Comed, the licenseo) submitted a request for changes to the Quad Cities Nuclear Power Station, Units 1 and 2, Technical Specifications (TS). The requested changes would revise the TS to allow an altomate methodology for quantifying Reactor Coolant System (RCS) leakage when the normal RCS leakage detection system is inoperable. This change would i
continue Quad Cities conformance to Generic Letter (GL) 88-01, "NRC Position on IGSCC 1
[Intergranular Stress Corrosion Cracking) in BWR [ Boiling Water Reactor) Austenitic Stainless Steel Piping," as delineated in NRC letter dated August 21,1990. The June 30,1999, submittal provided additional clarifying information that did not change the initial proposed no significant hazards consideration determination.
2.0 DISCUSSION NRC GL 88-01, issued January 25,1988, provided guidance in the form of NRC positionr; regarding IGSCC problems in BWR piping made of sustenitic stainless steel that is 4 inches or larger in nominal diameter and contains reactor coolant at a temperature above 200 degrees Fahrenheit during reactor power operation regardless of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) classification. One of the items which the GL requested licensees to address was the confirmation of the licensees' plans to ensure that the TS related to leak detection will be in conformance with the NRC positions on leak detection.
After review of your GL 88-01 response, the staff issued a letter dated August 21,1990, where Comed was requested to propose a TS emendment to include Limiting Conditions for Operation (LCO) on operability of sump monitonng instruments. The letter states: *Sina your plant has intergranular Stress Corrosion Cracking (IGSCC) weld Category E weldments,
, Generic Letter 88-01 provides an allowed outage time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> for repairing the drywell floor 9908200211 990004 PDR ADOCK 05000254 P
PDR j
2-drain sump monitoring system, or an orderly shutdown should be initiated. As an altemative, 1
the staff recommends that when the drywell sump monitoring system is inoperable, the operator should use a demonstrated manual method for determining leak rate, such as measuring the time to manually pump the sump at a fixed interval (4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />). The staff considers manual measurement a viable sump measuring method without hardship to the operator; therefore, this method could be added to the appropriate LCO section. With the manual method operable, the outage time for the drywell sump monitoring system could be extended to 30 days. However, if the sump pump and drywell sump monitoring systems are i,^ operable concurrently, then either system has to be repaired within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or an orderly shutdown should be initiated."
The NRC issued letters dated September 21,1995, for Amendment Nos.162 and 158 and June 28,1996, for Amendment Nos.171 and 167 for Units 1 and 2, respec+ively. These amendments incorporated the current TS that changed the LCO for drywtil leakage detection from reactor shutdown after 7 days of plant operation when the sump was found to be inoperable to the present TS that state to restore the drywell floor drain sump (DWFDS) system to operable status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, 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 the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
3.0 EVALUATION in a letter dated March 30,1999, as supplemented on June 30,1999, Comed proposed an amendment request to change TS Section 3/4.6.G and Bases Section 3/4.6.G to address an attemate method of determining RCS leakage. Quad Cities has found that when the flow totalizer for the DWFDS monitoring system is inoperable the TS require a plant shutdown if the totalizer is not declared operable within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The !icensee has found this to be unnecessarily restrictive because attemate means are available for quantifying RCS leakage when the DWFDS monitoring system is inoperable.
The cihanges proposed would provide additional flexibility for monitoring RCS leakage by makmg available other viable means of quantifying RCS leakage. One altemate method proposed by Comed is calculating flow rates using sump pump run times. The pump run times multiplied by the rated pump flow will be used to determine total volume of water pumped between surveillances. The pump flow rate will be periodically determined to monitor potential pump degradation. The licensee has monitored sump pump run times and pump flow rates since October 1998 and has found no significant pump degradation and the comparison of the measured and calculated flow rates have been consistent. The licensee states that attemate methodologies will be controlled by station procedures and reflected in the UFSAR.
The licensee has proposed the following changes to the TS in conformance with the guidance in GL 88-01 which is consistent with the improved 'schnical Specifications, NUREG 1433, Revision 1, and meets the intent of NRC staff letter dated August 21,1990:
1.
Modify TS section 3.6.G.2 to read:
2.
The drywell floor drain sump monitoring system.
This change adds the word monitoring to clearly indicate that this TS section is addressing the DWFDS monitoring ;,apabilities for RCS leakage and is acceptable.
)
t 2.
Modify TS section 3.6.G, Action 2 to read:
2.
With the drywell floor 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 altemate manual method of determining drywell floor drain sump flow rates by calculating flow rates using sump pump run l
times, AND within 30 days restore the drywell floor drain sump monitoring system to an OPERABLE status; 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 the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
This TS section was revised to indicate that if the DWFDS monitoring system is not made operable within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> the plant may continue to operate if an attemate method for monitoring RCS leakage has been establit.hed. The altemative is a manual method by using calculated flow rates using sump pump run times. The licensee has proposed this change in conformance with the guidance in GL 88-01, which is consistent with the improved Technical Specifications, NUREG 1433, Revision 1, and meets the intent of NRC staff letter dated August 21,1990; therefore, this change is acceptable.
3.
Modify TS section 4.6.G.2 to read:
2.
Performing a CHANNEL CALIBRATION of required leakage detection instrumentation at least once per 18 months.
This change more clearly specifies that the CHANNEL CAllBRATION of the DWFDS
. monitoring system is not just the totalizer as stated in the current TS Section 4.6.G.2, but it includes all required leakage detection instrumentation of the DWFDS. This change is acceptable.
4 Modify the last two sentences in BASES section 3/4.6.G to read:
)
With the drywell floor drain sump monitoring system inoperable, an attemate method using measured sump run-times for quantifying leakage can be i
employed for up to 30 days under administrative controls. Prims,ry containment i
atmosphere sampling for radioactivity can provide indication of chang (.s in leakage rates.
This Bases change describes the revision made in the TS which allows the use of an altemate means to measure RCS leakage and this is acceptable.
These TS changes also meet the statement in the August 21,1990, letter regarding inoperability of both the sump pump and drywell sump monitoring system, if both the sump pump and the DWFDS monitoring system are inoperable at the same time then either system has to be repaired within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or an orderly shutdown should be initiated. Quad Cities meets this criteria with Surveillance Requirement 4.6.H.2 for determining the primary containment sump flow rate at least once per,8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, not to exceed 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. If this requirement can not be met, the plant needs to 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 following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
i ;
These changes would allow the licensee to continue to operate the plant if the DWFDS monitoring system is fcund to be inaerable for up to 30 days if an altamate method has been established to quantify RCS leakage and this is acceptable.
4.0 STATE CONSULTATION
in accordance with the Commission's regulations, the Illinois State official was notified of the J
proposed issuance of the amendments. The State official had no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to the installation or use of c facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (64 FR 24194). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
6.0 CONCLUSiQN The Commission has concluded, based on the considerations discussed above, that: (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 Commissior/s regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: Robert M. Pulsifer Date: August 4, 1999 i
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