ML20126B237
| ML20126B237 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 12/14/1992 |
| From: | William Cahill, Woodlan D TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-92597, NUDOCS 9212220020 | |
| Download: ML20126B237 (5) | |
Text
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Log # TXX-92597 7%
File # 10010 906.3 915.6 1UELECTRIC wmiam J. cutan, Jr.
Gmup Vwe Premker U. S. Nuclaar Regulatory Commission Attention:
Document Control Desk Washington, DC 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
DOCKET WOS. 50-445 AND 50-446 ADVANCE FSAR SUBMITTAL - REVISED RCS HOT LEG RECIRCULATION SWITCH 0VER TIME Gentlemen:
The attachment to this letter provides an advance CPSES FSAR submittal to facilitate the NRC Staff review of the subject area in support of licensing Unit 2.
The attachment is organ, tea a; follows:
1.
A description / justification of each change.
2.
A copy of the revised FSAR pages (changes are indicated in the margin by the word " DRAFT *).
The attached material will be incorporated in CPSES FSAR Amendment 87 which is currently scheduled for December, 1992.
If you have any questions regarding this submittal, please contact Mr. Roy Cisneros at (214) 812-8814.
Sincerely.
William J. Cahill, Jr.
By:
D. R. Woodlan Docket licensing Manager RC/gjh Attachments c-Mr. J. L. Hilhoan, Region IV Resident Inspectors CPSES (2)
Mr. T. A. Bergman, NRR Mr. B. E. Holian, NRR 9212220020 921214 PDR ADOCK 05000445 P
PDR g
MU N Ohve 5,xe LB. 81 Dauas. Tcxn mo t
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Att achnent - 1 t o TXX-92597 -
d CPSES - FINAL SAFETY ANALYSIS REPORT (FSAR)
ANENDNENT / REVISION 87 DETAILED DESCRIPTION Page 1 PrGfix Page (Al amended)
Group Descrintion a
6.3 26 2
Revise FSAR Section 6.3.2.8 to change the RCS hot leg recirculation switchover time from 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />.
Revision The hot leg switchover time was revised as a result of an increase in service water temperature on FSAR LOCA-related analyses and.does not constitute an unreviewed 4
safety question.
A Safe Shutdown Impoundment (SSI) temperature profile had been provided for CPSES Units 1-and 2 and incorporated into calculations.
A subsequent analysis was made to address the effects of the revised SSI temperature profile on the Residual Heat Removal System (RHRS) cooldown capabilities. The 5
increase in the service water temperature did not impact the assumptions or results of_the LOCA-related analyses, with the exception of the hot leg switchover analysis. 'No changes to the plant Technical Specifications are required because the acceptance criteria has been met.
The change in hot leg switchover time is not considered to be significant.
Change Request-Number
SER/SSER Impact
- No Table 6.3-7 2
See Sheet No(s) :04 Revises FSAR Table 6.3-7. sheet 4 to change the RCS hot leg recirculation switchover time from 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />.
+
Revision Refer to the justification for FSAR Page 6.3-26 (Change Request No. SA-92-848).
Change Request Number
- SA-92 848.2 Commitment Register Number _: OP-0222-003 Related SER : 6.3.3 SSER :01 6.3.3 SER/SSER Impact
- No
]
15.6-23 2
Revises FSAR Section 15.6.5.2 to change the RCS hot leg recirculation switchover time from 16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> to 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br />.
Revision Refer to the justification for FSAR Page 6.3-26 (Change Request No. SA-92-848).
Change Request ~ Number
- SA-92-848.3 4
Commitment Register Number : NL-6015 Related SER : 6.3.3 SSER :01 6.3.3-SER/SSER Impact
- No
i Attachw nt 2 to TXX-92597 8*"' Id3 CPSES/FSAR 6.3.2.7 Provisions for Performance Testina Test lines are provided for performance testing of the ECCS as well as f
individual components. These test lines and instrumentation are shown in Figure 6.3-1.
All pumps have miniflow lines for use in testing operability. Additional information on testing can be found in Section 6.3.4.2.
i 6.3.2.8 Manual Actions Q212.40 j
No manual actions are required of the operator for proper operation of l
DRAFT the ECCS during the injection mode of operation. Only limited manual j
actions are required by the operator to realign the system for the cold leg recirculation mode of operation, and, before approximately 15 l
hours, for the hot leg recirculation mode of operation.
These 6
actions are delineated in Table 6.3-7.
Q212.113 The changeover from the injection mode to recirculation mode is l
initiated automatically and completed manually by operator action from i
22 the Control Room.
Protection logic is provided to automatically open the two Safety Injection System (SIS) recirculation sump isolation j
valves when two of four Refueling Water Storage Tank (RWST) level channels indicate an RWST level less than'a low-low level setpoint, in conjunction with the engineered safeguards actuation signal ("S" signal). This automatic action would align the two r u idual heat removal pumps to take suction from the containment sump and to deliver directly to'the RCS.
It should be noted that the residual heat removal pumps would continue to operate during this changeover from injection mode to recirculation mode.
The two charging pumps and the two safety injection pumps would continue to take suction from the RWST, ft110 wing the above automatic action, until manual operator action is taken to align these pumps in series with the residual heat removal pumps.
I.
i Draft Version 6.3-26 a
-ern,
,my
.~,
t
. to TXX-92597 CPSES/FSAR sheet 2 of 3 TABLE 6.3-7(Sheet 4)
SWITCHOVER FROM COLD LEG-RECIRCULATION TO HOT LEG RECIRCULATION 22 l
At approximately 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br /> after the accident, hot leg recirculation ORAFT shall be initiated.
The following manual operator actions are required to perform the switchover operation from the cold leg 22 recirculation mode to the hot leg recirculation mode.
SWITCHOVER STEPS 22 STEP 1:
Close the residual heat removal pump discharge cold leg 22 l
header isolation valves (8809 A/B).
l STEP 2: Open the residual heat removal pump. discharge crossover 22 isolationvalves(8716A/B).
i STEP 3: Open the residual heat removal pump discharge hot leg header 22 isolationvalve(8940).
STEP 4:
Stop safety injection pump No. 1.
22 STEP 5:
Close the corresponding safety injection pump discharge 22 crossover header isolation valve (8821A).
STEP 6: Open the corresponding safety injection-pump discharge hot 22
-leg header isolation valve (8802A).
i
' STEP 7: : Restart safety-injection pump No. 1.
22 STEP 8:
Stop safety injection pump No. 2.
22 STEP 9: Close the corresponding safety injection pump discharge 22 crossover isolation valve (88218).
l STEP 10: Close the safety injection pump discharge cold leg header 22 j
isolationvalve(8835).
l i
q Draft Version
i to TXX-92597 CPSES/FSAR sbcet 3 of 3 Continued operation of the ECCS pumps supplies water during long term cooling.
Core temperatures have been reduced to long term steady state levels associated with dissipation of residual heat generation.
I l
After the water level of the refueling water storage tank reaches a j
minimum allowable value, coolant for long term cooling of the ccre is obtained by switching to the cold leg recirculation phase of operation i
in which spilled borated water is drawn from the engineered safety features sumps by the low head safety injection (residual heat removal) pumps and returned to the RCS cold legs. The Containment 6
Spray System continues to operate to further reduce Containment
]
pressure. Within approximately 15 hours1.736111e-4 days <br />0.00417 hours <br />2.480159e-5 weeks <br />5.7075e-6 months <br /> after initiation of the ORAFT 1
LOCA, the ECCS is realigned to supply water to the RCS hot legs in order to control the boric acid concentration in the reactor vessel, j
Descriotion of Small Break LOCA Transient i
As contrasted with the large break, the blowdown phase of the small break occurs over a longer time period.
Thus,'for the small break LOCA there are only three characteristic stages, i.e., gradual I
blowdown in which the decrease in water level is checked, core i
recovery, and long term recirculation.
15.6.5.3 Core and System Performance 4
15.6.5.3.1 Mathematical Model The requirements of an. acceptable ECCS evaluation model are presented l
in Appendix K of 10CFR50 (3].
4 i
15.6-23 Draft Version
. -,