ML20149C624
| ML20149C624 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 02/03/1988 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20149C616 | List: |
| References | |
| NUDOCS 8802090220 | |
| Download: ML20149C624 (3) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION n
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W ASHING TON. D. C. 20555
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMEhDMENT NO.104 TO FACILITY OPERATING LICENSE NO. DPR-29 AND AMENDMENT N0.100 TO FACILITY OPERATING LICENSE NO. DPR-30 COMMONWEALTH EDIS0N COMPANY AND IOWA-ILLIN0IS GAS AND ELECTRIC COMPANY QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2 DOCKET N05. 50-254 AND 50-265
1.0 INTRODUCTION
As a result of an ongoing, comprehensive, internal review of DPR-29, Appendix A, Technical Specifications (TS) by the Commonwealth Edison Company (Ceco, the licensee) Quality Assurance Departnent, several inconsistencies were identified between TS requirements and actual plant design, configuration, and/or procedures. One such finding was submitted to the huclear Regulatory Conin1ssion (NRC) as a request for temporary waiver of compliance and TS emendment on October 6, 1987.
This request was subniitted to revise the methodology recuired for ensuring discharge lines in High Pressure Core Injection (HPCI) and Reactor Core isolation Cooling (RCIC) Systems remain filled.
By another letter dated October 6,1987, the NRC approved a temporary waiver of compliance for affected TS Section 3.5.G.2.
It was determined that actual station practice and system configuration were adequate to meet the safety (to expire after sixty days).
intent of TS 3.5.G.2, and was therefore acceptable on an interin basis However, on November 24, 1987, following a series of cnnference calls with NRC staff, CECO supplemented their original application in order to increase the surveillance frequency requirement for venting HPCI/RCIC discharge lines, when aligned to the torus, from "monthly" to every "twenty-four hours". The proposed TS amendment (including its supplement) was subsequently renoticed in the Federal Register on December 16, 1987 for public coninent.
In addition, an extended TS waiver of compliance was issued on December 4,1987, for an additional 60 days, g!onanBES$h*
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- .f 2.0 EVALUATION Limiting Conditions for Operation of TS 3.5 G requires that discharge piping (, from pump discharge to last check valve, must be filled for Core Spray CS), low Pressure Core Injection (LPCI), HFCI, and RCIC Systems.
The discharge lines of both low pressure (CS and LPCI mode of Residual Heat Removal (RHR) System) Emergency Core Cooling Systems (ECCS) and high pressure cooling systems (HPCI and RCIC) must be maintained between 40 psig and 90 psig, which necessitates using a special ECCS fill system pump.
In actual operation, only low pressure systems require use of the fill pump for reasons discussed below.
For high pressure systems, assurance of filled discharge lines has been achieved by maintaining an adequate level in the Contaminated Condensate Storage Tank (CCST), which is the normal water source for both HPCI and RCIC.
At Quad Cities, pressure switches and corresponding control room alarms are installed on CS and LPCI mode of RHR, but no pressure switches or
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alarms are installed on HPCI or RCIC.
The 90 psig upper limit setpoint ensures the low-pressure cooling pump discharge pressure interlock is not defeated. This interlock applies to CS and LPCI mode of RHR, but not to HPCI or RCIC. HPCI and RCIC operate at pressures above the low-pressure 1
interlock setpoint. The 40 psig lower limit setpoint ensures discharge piping up to the last check valve remains full. CS and LPCI mode of RHR are nomally lined up to take a suction from the suppression chamber.
Due to relative elevation differences between the suppression chamber and the last check valve in either CS or LPCI mode of RHR, a minimum pressure of 39 psig is required to maintain the discharge piping of these systems full.
This pressure is maintained by valving in an ECCS fill system pump.
l During routine operations,HPCI and RCIC are aligned to take suction from the CCSTs.
Due to relative elevation differences between the CCSTs and the last check valve in either HPCI or RCIC, the discharge piping of these systems will remain full by maintaining a mir h m CCST level of 9.5 feet.
This passive method assures discharge piping or HPCI and RCIC are filled, without reliance upon an active method (ECCS fill system pump).
NRC staff concludes that ensuring HPCI and RCIC system discharge lines remain full can be accomplished by maintaining a minimum level in the j
CCSTs.
In fact, a passive fill method is preferable because it does not rely upon a single active system (ECCS fill system pump).
Furthermore, this methodology is consistent with actual plant instrumentation which only includes pressure switches and control room alarms on the discharge lines of low pressure ECCS systems.
Consequently, NRC staff has determined that Ceco's amendment application of October 6,1987, is acceptable.
On November 24, 1987 CECO proposed to increase the surveillance frequency for manually venting the HPCI/RCIC discharge piping whenever the suction supply is diverted to the torus because of CCST unavailability. This will provide odditional assurance that the discharge piping remains full under these abnormal conditions.
The NRC staf f has concluded that this supplement to the original 1
application is also acceptable.
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3.0 ENVIRONMENTAL CONSIDERATION
These amendments involve a change to a requirement with respect to the use l
of a facility component located within the restricted area as defined in 10 CFR Part 20, and changes surveillance requirements.
The staff has detemined these amendments involve no significant increase in the amounts, and no sigr.ificant change in the types of any ef fluents that may be released offsite and there is no significant increase in individual or cumulative occupational radiatier exposure. The Commission has previously issued a l-proposed finding these amendments involve no significant hazards consider-ation and there has been no public cotwent on such finding.
Accordingly, t
these amendments meet the elicibility criteria for categorical exclusion setforthin10CFR51.22(c)(9).
Pursuant to 10 CFR 51.22(b) no environmental impact statement nor environmental assessment need be prepared in connection with the issuance of this amendment.
4.0 CONCLUSION
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The staff has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance the health and safety of the public will not be endangered by operation in the prnposed manner, and I
(2) such activities will be conducted in compliance with the Comission's regulations and the issuance of this an,endment will not be inimical to the common defense and security nor to the health and safety of the i
- public, j
1 Principal Contributor:
T. Ross Dated: February 3, 1988 t
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