NL-88-1227, Monthly Operating Rept for Oct 1988 for Rancho Seco Nuclear Generating Station Unit 1

Monthly Operating Rept for Oct 1988 for Rancho Seco Nuclear Generating Station Unit 1

ML20195F895
Person / Time
Site:	Rancho Seco
Issue date:	10/31/1988
From:	Crunk S, Mueller M SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
NL-88-1227, NUDOCS 8811220401
Download: ML20195F895 (7)

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i OCI00ER_lS88

SUMMARY

OF PLANT OPERATIONS j Rancho Seco operated at approkimately 63% power until it was increased to the 92% level which was reached at 1110 hours0.0128 days <br />0.308 hours <br />0.00184 weeks <br />4.22355e-4 months <br /> on October 13. The plant automatically shutdown at 0614 hours0.00711 days <br />0.171 hours <br />0.00102 weeks <br />2.33627e-4 months <br /> on October 14 on loss of Reactor Coolant Pumps due to an offsite grid disturbance. Reactor restart occurred at 0451 hours0.00522 days <br />0.125 hours <br />7.457011e-4 weeks <br />1.716055e-4 months <br /> on October 16 and Rancho Seco was placed on line at 0400 hours0.00463 days <br />0.111 hours <br />6.613757e-4 weeks <br />1.522e-4 months <br /> on October 17. The 92% power level was reached at 0425 hours0.00492 days <br />0.118 hours <br />7.027116e-4 weeks <br />1.617125e-4 months <br /> on Octobvr 18.

The plant was taken off line at 0639 hours0.0074 days <br />0.178 hours <br />0.00106 weeks <br />2.431395e-4 months <br /> on October 25 due to an approximate one-gallon per minute reactor coolant system leak. The reactor was brought critical at 1154 hours0.0134 days <br />0.321 hours <br />0.00191 weeks <br />4.39097e-4 months <br /> on October 29. Tne plant was put back on line at 2115 hours0.0245 days <br />0.588 hours <br />0.0035 weeks <br />8.047575e-4 months <br /> on October 29 and power was increased to about 92% power where it remained through month's end.

SUMARY OF CHANCES IN ACCORDANCE HI1H 10 CFR 50.59 The plant staff accepted documentation packages in October 1988 for the facility changes des:ribed below which required detailed safety analysis.

These changes were reviewed in accordance with the Technical Specifications by l the Plant Review Committee (PRC) and the Management Safety Review Comittee 1 (HSRC). There were no documentation packages completed for procedure changes, tests or experiments during October "188.

1. ECN A-5618 installed flanges in the piping adjacent to isolation valves NSH 013 and NSW 014. Dereby eliminating the necessity to cut the pipe when valve removal is necessary. This change does not increase the probability of occurrence or the consequences of an accident or malfunction of equipment important to Aafi'.y previously evaluated in the FSAR or create the possibility for an accident or malfunction of a different type than any evaluated previously in the FSAR. This change does not involve an unreviewed safety question. (Log No. 595)

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2. ECN A-3431 provided a major redesign of the control rod matt on the main fuel handling bridge. The modification included replacing the inner telescopic cylinder with a cable hoist mechanism, replacing the finger

, type grapple with a ball lock grapple. and changing the grapple operating actuation from hydraulic to air actuation.

There are two probabie types of failures. One would be failure of the up limit switch and the overload switcn which could result in an overstress of the cable and complimentary parts. To preclude this failure a crushable pad is installed to absorb the load and a floating link is installed around the load cell to absorb the load if it should fall. The other failure is a release of the grapple allowing a withdrawn control rod assembly to drop. There is an automatic lockout and a switch that would have L fall simultaneously for this to occur. This modification increased reliability and the design closely resembles the manual tool that has been used successfJ11y.

[M'12?001 est03 d F; "DOW 0500033 ,f' FDC j

. Thus,,this change does not increase the probability of occurrence or the donsequences of an accident or malfunction of equipment important to

, safety-previously evaluated in the FSAR or create the possibility for an accident or malfunction of a different type than any evaluated previously in the FSAR. This change does not involve an unreviewed safety question. (Log No. 322)

MAJOR SAFETY-RELATED MAINTENANCE. TESTS AND MODIFICATIONS NOT REQUIRING DETAILED SAFETY ANALYSES

1. Maintenance was performed on the Main Feedwater Pumps, "A" Reactor Building Spray Pump, "B" High Pressure Injection Pump, and the "A" TOI Diesel. Leak repair was performed to correct the leak identified in the reactor coolant system.

2. ECN A-5727, Revision 0, provided a permanent priming water supply to the Auxiliary Lube Oil Centrifuge, 1

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REFUELING INFORMATION REQUEST

1. ,Name'of Facility Rancho Seco Unit 1

2. Scheduled date for next refueling shutdown: July 1. 1989

3. Scheduled date for restart following refueling: August 29. 1989

4. Technical Specification change or other license amendment required:

a) Change to Rod Index vs Power Level Curve (TS 3.5.2) b) Change to Core Imbalance vs Power Level Curve (TS 3.5.2) c) Tilt Limits (TS 3.5.2)

5. Scheduled date(s) for submitting proposed licensing action: January 15. 1989

6. Important licensing considerations associated with refueling: N/A

7. Number of fuel assemblies:

a) In the core: 177 b) In the Spent Fuel Pool: 316

8. Present licensed spent fuel capacity: 1080

9. Projected date of the last refueling that can ba discharged to the Spent Fuel Pool: _QfLctd er 3. 2001 i

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C AVERAGE DAILY UNIT POWER LEVEL

.. DOCKET NO. 50-312 UNIT Rancho Seco Unit 1 DATE 10/31/88 COMPLETCO BY Marla Mueller TELEPHONE (916) 452-3211 MONTH October 1988 .

DAY AVERAGE DAILY P0HER LEVEL DAY AVERAGE DAILY P0HER LEVEL (MHe-Net) (MHe-Net) 1 528 17 314 2 544 18 771 3 569 19 810 1

4 566 20 818 5 570 21 816 ,

6 566 22 813 -

7 652 23 _310 _ .

8 564 24 817 9 563 25 ___

770 l 1

10 567 26 , 0 4

11 _ 560 27 . . _ _ . . . _ Q .__. _

12 566 28 0 13 783 29 100 14 816 30 470 15 0 31 784 16 0 INSTRUCTIONS On this format, list the average daily unit power level in HHe-Net for each day in the reporting month. Compute to the nearest uhole regawatt.

OPERATING DATA'RElVRT

.. DOCKET NO. 50-312 DATE 10/31/88 COMPLETED BY Marla Muslier TELEPHONE (916) 452-3211 OPERATING STATUS

1. Unit-Name: Rancho Seco Unit 1 Notes:  ;

2. Reporting Period: October 1983

3. Licensed Thermal Power (MHt): 2.772

4. Nameplate Rating (Gross MHe): 963

5. . Design Electrical Rating (Net HHe): 918 ,

6. Maximum Dependable Capacity (Gross MHe): 917

7. Maximum Dependable Capacity (Net MHe): 873 ,

. 8. If changes Occur in Capacity Ratings (Items Number 3 Through 7) Since Last Report, Give Reasons: N/A

9. Power Level to Hhich Restricted, If Any (Net MHe): N/A

10. Reasons For Restrictions, If Any: N/A This Month Yr-to-Date Cumulative

11. Hours in Reporting Period 744 ___._7.319 118.2.03

12. Number of Hours Reactor Was Critical ___

596.2 4.598.2 58.920,1___ [

13. Reactor Reserve Shutdown Hours __

0 0 10.300.2 b

14. Hours Generator On-Line 563.6 4.298.3 , 54.662.1 1

15. Unit Reserve Shutdown Hours 0 0 1.210.2 r

16. Gross Thermal Energy Generated (MHH) 1.155.669 7.169.824 _135.031.512___

17. Gross Electrical Energy Generated (HHH) 383.832 _2.347.40Z__ _43.870.599

+ 18. Het Electrical Energy Generated (MWH) 353.761 2.095.302 __ 40.327.328 j

19. Unit Service Factor 75 81_ 58.,21_ _45.0%  ;

20. Unit Availability Factor 15.8% 58.7% 47.1% _

21. Unit Capacity Factor (Using HDC Net) 54.5L _3.7.E_ ___

10.91__

22. Unit Capacity Factor (Using DER Net) 51.8% 31. 2% __ 37.0%._

23. Unit Forced Outage Rate 24. 2%.. 35.1%_ 42.9% i

24. Shutdowns Scheduled Over Next 6 Months (Type, Datr, e and Duration of Each):  !

1

_Rone

25. If Shut Down At End Of Report Period, Estimated Date of Startup: N/A l

26. Units In Test Status (Prior to Commercial Operation): Forecast Achieved [

INITIAL CRITICALITY N/A N/A INITIAL ELECTRICITY N/A N/A COMMERCIAL OPERATION N/A N/A J

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DOCKETNO. 50-312 UNIISHUTDOWNS AND POWER REDUCTIONS UNITNAME Rancho e, pen -

DATE _October 31. 1988 ,

COMPLETED 3Y M. Mue11er REPORT MONTH October l_988 TELEPHONE (916) 452-3211 1

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"Y5 Lk.cnsee ,Ev, *g a. Cause & Corressise No. Dans S

c- %2 s 3:& Eant :T

$0 O Action lo j@ 5 j$ Repo a [Q Prevent Recurrence .

6 10 88-10-14 F 69.8 A 3 88-15 N/A N/A Reactor tripped from loss of Reactor Coolant Pumps due to offsite grid disturbance.

Corrective action was to extend :.ho phase to phase fault protection past the substation where the fault occured .

11 68-10-25 F 110.6 A 1 88-14 AB ISV Shut down due to Reactor Coolant.

RTV Leakage.

Immediate corrective action was seal-injection repair. Long term action is

1) to disassemble the Pressurizer Block Valve and repair / rework valve stem as necessary and install new packing, and

' 2) replace the Instrument Root Valve.

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3 4 l 2 F FasteJ Reason: Me. hod: Exhibit G-Instructions I

A Equipment Failure (Explain) l-Manual for l' reparation of Data

! S St heduled 2-Manual Scram- Entry Sheets for Licensee B-Maintenance of Test C-Refueling . 3-Automatic Scram. Event Report tLER) File (NUREG-D-Regulatory Restriction 44:her (Explain) 01611 j

E-Operator Training & License Examination F Administrative $

i G-Operational Error (Explain) Exhibit I - Sanw S. usee I

s2/77) litther (E splain) .

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, e Nishiun SACRAMENTO MUNICIPAL UTILITY DISTRICT C P. O. Box 15830, Sacramento CA 95852-1830,(916) 452-3211 AN ELECTRIC SYSTEM SERVING THE HEART OF CALIFORNIA NL 88-1227 NOV 15 1988 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Hashington, DC 20555 Docket No. 50-312 Rancho Seco Nuclear Generating Station License No. DPR-54 OPERATING PLANT STATUS REPORT Attention: Gectge Knighton Ericlosed is the October 1988 Honthly Operating Plant Status Report for the Rancho Seco Nuclear Generating Station. The District suomits this report pursuant to Technical Specification f.9.3.

Sincerely, h

Steve m. Crunk Manager Nuclear Licensing Enci (5) cc: J. B. Hartin, NRC, Halnut Creek INP0 R. Twilley, Jr.

[$Y RANCHO SECO NUCLFAR GENERATING STATION D 1444o Twin Cities Road. Herald, CA 95638 9799;(2o9) 333 2935 I):