ML20090F549
| ML20090F549 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 06/30/1983 |
| From: | Dewitt R CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 23227, NUDOCS 8307060057 | |
| Download: ML20090F549 (6) | |
Text
a b.
Consumers Power a -" = = =
Vice President b
Nuclear Operations General offkes: 1945 Parnall Hood, Jackson, Michigan 49201 + (517) 788-1217 June 30, 1983 Harold R Denton, Director Office of Nuclear Reactor Regulation US Nuclear Regulatory Commission Washington, DC 20555 MIDLAND NUCLEAR C0 GENERATION PLANT MIDLAND DOCKET NOS 50-329, 50-330 NATURAL. CIRCULATION TESTING FILE: 0928.6 SERIAL: 23227 This letter provides information on the subject of natural circulation testing addressing concerns on boron mixing and use of reactor vessel head vent temperature indication. The information, which was requested by the NRC during a telephone conference call on June 17, 1983, responds to topics related to Open Items #7 and #9 and Confirmatory Issue #7.
Open Item #7; Boron Mixing During Shutdown With Natural Circulation Use of the letdown line during natural circulation tests should not perturb the test results for two reasons:
a) Letdown constitutes less than one percent of expected natural circulation flow and therefore should not affect results.
b) The longterm cooling analysis presented in BAW-10103A indicates that a core flow of 3000 gpm (416 lbs/sec) will prevent the boron from concentrating. Natural circulation flow should exceed 3000 gpm and ensure mixing in the vessel. A six weight percent solution will be provided as the source of borated water during this mixing test.
Open Item #9; Reactor Vessel Head Vent Temperature Indication The reactor vessel head vent temperature will be used to determine the direction of natural circulation flow. Flow direction will be determined as follows:
a) For reactor vessel head vent temperature greater than hotleg temperature, flow is in the positive direction.
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b) For reactor vessel head vent temperature equal to hotleg temperature, (plus or reinus 10 F), flow is in the negative direction.
c) For reactor vessel head vent temperature less than hotleg temperature, (temperature differential of at least 10 F and increasing), flow is stagnant.
Included as an attachment is a copy of an approved FSAR Change Notice on the topic above to be included in the next FSAR revision.
It is expected that the information provided in addition to the approved FSAR Change Notice should provide the NRC with the information necessary to complete Open Items 7 and 9 and Confirmatory Issue 7.
-YD RBD/MFC/dlm CC RJCook, Midland Resident Inspector JGKeppler, Administrator, NRC Region III HAMiller, NRC I
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CONSUMERS POWER COMPANY Midland Units 1 and 2 Docket No 50-329, 50-330 Letter Serial 23227 Dated June 30, 1983 At the request of the Commission and pursuant to the Atomic Energy Act of 1954, and the Energy Reorganization Act of 1974, as amended and the Commission's Rules and Regulations thereunder, Consumers Power Company submits information on boron mixing and reactor vessel head vent temperature indications during natural ciruclation testing.
CONSUMERS POWER COMPANY By M
2 R B Dewitt, Vice President-Nuclear Operations Sworn and subscribed before me this A day of d s,f 943 D _c Y.O Notary Public Jackson County, Michigan My Commission Expires' h P,,efgx5 f
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QUALITY ASSURANCE PROGRAM SAR CHANGE NOTICE
- 1. h JOB NO.
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- 2. DISCIPLINE / COMPANY O
- 3. No 038 b/f8/83
- 4. ORIGINATOR
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- 6. REFERENCED SECTIONS OF SAR FSAR Cross Reference Index has been checked and affected g,4g FSAR pages are attached which reflect appropriate changes.
,it '- -
- 7. DESCRIPTION OF CHANGE Is the purpose of this change for anything other than:
Closing an ACRS/SER open item, correcting an editorial error or providing infor=ation already co::nitted to in NRC correspondence?
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No If yes, provide furthur justification for the change in Block 9 A DD/7 h A4L De7 MMS /A/cwoED /AJ A/C 76ST
- 8. REFERENCED SPECIFICATIONS OR DRAWINGS Ah34/5
- 9. JUSTIFICATION
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- 10. BECHTEL DISCIPLINE INTERFACE REVIEW:
INTERFACING STAFF REVIEW:
C ARCH C PLANT 05N C ARCH C MECH C CIVIL CPGAE C CIVIL C NUCLEAR C CONT 4ot SYS C STRESS C CONTROLSYSTEM C PLANT DSN C ELEC C OTHER C ELEC C REUA81UTY E WN CLEAR C GEOTECH C STRESS he$ Yt hn
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- 11. REVl'EWED BY DATE
- 12. REdWED B/
DATE
- 13. REVIEWEDN DATE IGroup Supervisor)
(SAR COORDINATOR)
(NUCLEAR ENGINEER)
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- 14. CONCURRENCE BY DATE
- 15. APPROVED BY(CPCo)
DATE
- 16. CONCURRENCE BY DATE IPROJECT ENGINEER)
(NSSS SUPPLIER)
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MIDLAND 1&2-FSAR 14A.4.22 NATURAL CIRCULATION TESTING l 47
.)
1.
Purpose 43 1.1 Demonstrate the initiation, maintenance, and recovery from the natural circulation mode.
1.2 Demonstrate the performance of the auxiliary feedwater level rate control system.
1.3 Demonstrate the RCS can be uniformly borated while in natural circulation.
1.4 Demonstrate the capability to cooldown the RCS via natural circu;ation using the OTSGs.
Determine acceptable cooldown rate in natural circulation.
1.5 Demonstrate tae performance of the subcooling monitor.
2.
Prerequisites 2.1 The startup test program has progressed to the point where a minimum of 1% rated full power from decay heat is possible.
47 2.2 Reactor is shutdown and subcritical by at least 1%
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k/k.
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2.3 Four RCPs running.
2.4 OTSG level at low level limit.
2.5 Normal RCS temperature and pressure.
3.
Test Method n
3.1 As quickly as possible, trip pressuri::er heater banks (1-4), reactor coolant pumps, main steam isolation valves, and main feedwater pump.
Isolate letdown.
Verify AFW actuates and is raising OTSG levels to natural circulation setpoint.
Control RCS pressure with PORV and OTSG pressure with the POAV.
Stablize plant in natural circulation.
3.K3 Restore equipment to operation with the exception of the reactor coolant pumps and main feedwater pumps.
3. X'/ With the plant in natural circulation (actual decay heat available), a batch addition of Beeeft to increase RCS Boron concentration b pproximately 200 ppm will be initiated.
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3.7. tAondor dhe reector vesse] head vent th ;;,s t*e ereptyft.1"o BSCekoln Revision 47 t/ent f/oW <M//1tc NE,4A.4-23 12/82
MIDLAND 1&2-FSAR 3.K5 sampling will continue to verify RCS concentration increase cf > 100 ppm and trend is as expected.
(
- 3. 9(lp An RCS cooldown will be initiated using the turbine bypass valves to demonstrate a cooldown in Tavg of at least 100F.
4.
Acceptance Criteria 4.1 Natural circulation has been established.
Indications of natural circulation are:
a.
A stable loop LT with TC near Tsat of the OTSGs.
b.
A small or negligible difference between incore thermocouple readings and hot leg 47 temperature readings.
c.
RCS pressure and pressurizer level stable prior to cooldown.
4.2 Boron has nixed in the RCS to in' crease the concentration by at least 100 ppm.
The RCS concentration is trending as expected toward the calculated equilibrium value.
.f 4.3 RCS Tavg has been reduced approximately 100F by
(
natural circulation cooldca:n with no void formation in the RCS.
4.4 AFW level rate control prevents overcooling (T avg
< 52SF) as predicted.
A.5-Reoefor vesse 7 />eed vent &m,oeredure.
remems above />d leg denperature d
dermy est.
Revision 47 14A.4-24 12/82
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