IR 05000335/1992013
| ML17227A575 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 08/19/1992 |
| From: | Burnett P, Crlenjak R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | |
| Shared Package | |
| ML17227A574 | List: |
| References | |
| 50-335-92-13, 50-389-92-13, NUDOCS 9208310090 | |
| Download: ML17227A575 (10) | |
Text
~P,g REMI P
e
Cy O
I ~
Ic e gO
++*++
UNITED STATES NUCLEAR REGULATORY COMMISSION
REGION II
101 MARIETTASTREET, N.W.
ATLANTA,GEORGIA 30323 Report Nos.-:
50-335/92-13 and 50-389/92-13 Licensee:
Florida Power and Light 9250 West Flagler Street Miami, FL 33102 Docket Nos.:
50-335 and 50-389 License Nos.:
DPR-67 and NPF-16 Facility Name: St. Lucie 1 and
Inspection Conducted:
June
- 26, 1992 Inspector:
Approved by:
P.
. Burnett
.e R. V. Crle jak, Chic Operational Programs Section Operations Branch Division of Reactor Safety Date Signed te igned SUMMARY.
Scope:
This routine announced inspection addressed witnessing and review of Unit 2, cycle 7, startup tests and review of completed core performance surveillance tests-for both units.
Results:
Recent modifications to the source range nuclear instruments improved reactivity monitoring in mode 2 and enabled those 'instruments to be operable throughout the approach to criticality.
The licensee employed extensive and intensive trouble shooting activities to assure the source range instruments were functional and reliable prior to changing reactivity.
(Paragraph 2.a)
Initial criticality for Unit 2 cycle 7 and the subsequent zero power tests were well controlled and performed satisfactorily.
The use of an on-shift management observer and reactivity manager enhanced the operat'ions.
(Paragraph 2.b).
9208310090 920819 PDR ADOCK 05000335
Routine surveillances of core performance for Unit
cycle 11 have been performed with satisfactory frequency and results.
(Paragraph 3)
The at-power measurements of moderator temperature coefficient were conducted under the required conditions and with acceptable results for Unit
cycle 6.
(Paragraph 4)
No violations or deviations were identifie e REPORT DETAILS Persons Contacted Licensee Employees
- G. Boissy, Plant General Manager H. Buchanan, Health Physics Supervisor C. Burton, Operations Manager
- R. Dawson, Maintenance Manager
- J. Dyer, Quality Control Supervisor
- R. Englmeier, Nuclear Assurance Manager
- J. Holt, Plant Licensing Engineer
- C. Leppla, Instrument and Control Supervisor
- L. McLaughlin, Licensing Manager
- D. Sager, St. Lucie Plant Vice President J. West, Operations Supervisor
- E. Wunderlich, Reactor Engineering Supervisor Other licensee employees contacted included engineers, operators, and office personnel.
NRC Resident Inspectors
- S. Elrod, Senior Resident Inspector M. Scott, Resident Inspector
- Attended Exit 'interview on June 26, 1992.
2.
Acronyms and initialisms used in this report are defined in the final. paragraph.
Unit 2, Cycle 7 Startup Tests (72700, 61705, 61708, 61710)
I The cycle 7 design was evaluated under PC/M No.
067-292E, which was reviewed by the inspector.
The core was deigned for 10,725 z 100 EFPH (447 EFPD).
The entire core is of DRFA design.
Supplement 1, June 1, 1992, provided the reload core design, Attachment 7.5, Startup and Operation Data, Attachment to F2-92-051, and the St. Lucie Unit 2 Cycle 7 Startup Test Predictions.
The inspector reviewed the procedures listed below prior to performa'nce for this startup; witnessed portions of the performance of the procedures, and reviewed the results of the tests.
a.
PTP-2-3200088 (Revision 3), Unit 2 Initial Criticality following Refueling, was completed on June 24, 1992.
Prior to any control rod withdrawal, the RCS was
-
confirmed to be at a boron concentration more than 250 ppmB in excess of the calculated CBC for Group 5 at
in. withdrawn.
No statistical reli'ability check of the startup channels was required by this procedure.
However, reactor engineering personnel were observed performing chi-squared tests on both startup channels in accordance with REDI 7.1 (dated October 14, 1990).
During repetitive tests, channel 2 was consistently acceptable, while channel
was consistently unacceptable.
Persistent testi'ng and searching revealed the problem source to be outside the channel instrumentation.
A fluorescent trouble light had been left on in the passage
'ehind the instrument racks and was inducing 60 Hz noise into channel 1.
Once the fluorescent light was removed, channel 1 performed acceptably.
During the approach to criticality, there were several extended periods in which reactivity was not changing.
The inspector was able to verify continued proper operation of the startup channels during those periods, by performing additional chi-squared tests.
Base counts were obtained for the two startup channels and two of the four wide-range channels prior to withdrawing any of the CEAs.
Shutdown group A was withdrawn-to the UEL and then 1/M data were obtained and plotted for the neutron monitors in use.
The procedure was repeated for shutdown group B.
CEA groups 1-4 were withdrawn in overlap and 1/M data obtained and plotted when each group reached its UEL.
The final 1/M for CEA motion was obtained with group 5 at 60 in." withdrawn.
Base count rates were.,reinitialized and RCS dilution begun at
gpm.
1/M was calculated and plotted for every 1500 gallons of dilution water added.
Criticality'as achieved with group 5 at 60 in. withdrawn following mixing after adding a total of 9000 gallons of dilution water.
For the first time ever, the unit was made critical in the. source range.
That achievement was the result of a modification performed during the outage; the countrate at which high voltage to the detectors was interrupted was increased from 2000 cps to 10,000 cps.
At that'point the wide range monitors had been responding proportionally to the increase in neutron population for more than a decade on the source range.
However, the wide range detectors did not appear to respond to the changing neutron population until withdrawal of rod group 4, by which time reactivity had increased by about 4000 pcm.
Since Unit 1 has no source range instruments, the
inspector questioned the capability of the Unit 1 wide range instruments to monitor all reactivity changes.
Reactor engineering personnel stated that the Unit,1 wide range instruments were more sensitive than those on Unit 2 and were adequate to monitor the entire approach to criticality. It was also noted that Unit 2 TS refer to the source range instruments only in the refueling section, 3/4.9.
However, the source range instruments are clearly needed in Unit 2 for reactivity monitoring in modes 5, 4, 3, and 2 also.
The inspector has discussed the issu'e of TS requirements for source range operability with NRR and determined that further NRC review is warranted.
Prior to entering this procedure, the on-shift management observer, present pursuant to AP-0010120, briefed operations and test personnel on the conduct of the test and the criteria for securing or withdrawing from the test.
Although the term is not defined in AP-0010120, the observer described himself as the reactivity manager, and the management observers functioned in that capacity throughout this and subsequent startup tests.
PTP-3200091 (Revision 0) Reload Startup Physics Testing, was conducted during the interval June
- 26, 1992.
Tests were conducted in accordance with the following appendices to this procedure:
APPENDIX A:
Reactivity Computer Checkout, which first determined the point of adding heat; so that reactivity computer measurements could be kept significantly below that flux level to prevent uncorrectable fuel doppler effects from influencing the reactivity measurements.
The instructions for initiating and measuring both positive and negative periods were sufficiently detailed
~ to assure reproducible results.
The reactivity computer was shown to yield acceptable results for reactivity inputs ranging from -30 pcm to +30 pcm, and subsequent applications of the computer were limited to that range of reactiyities.
APPENDIX C:
All Rods Out Critical Boron Concentration, yielded a CBC of 1514 ppmB, which was acceptably close to the predicted value of 1524 ppmB.
APPENDIX D: Isothermal Temperature Coefficient, produced four measurements, each with a temperature change of at least 5'F.
The resulting ITCs ranged from 0.466 pcm/'F to 0.816 pcm/'F, which is acceptable internal consistency.
The average value of -0.63 a 0.15 pcm/'F was in acceptable agreement with the predicted value of-0.49 pcm/4F.
The resulting MTC of +0/94 pcm/'F was well
below the TS limit.
APPENDIX E:
Rod North Measurements by Rod Swap, also controlled the measurement of the reference group (group B) during boron dilution.
During the measurement of the reference bank worth, two reactivity computers were in use.
Licensee personnel noted that the trace of the
"primary reactivity computer produced'
span about
percent greater than the DRC being tested.
Post-measurement review of the primary reactivity computer revealed that, after calibration, the scaling had been misadjusted by a factor of 1.2.
The NSSS vendor, the supplier of the primary reactivity computer, agreed with that adjustment of the
"raw data.
The measured values tabulated below reflect the adjustment of the data by the factor of 1.2.
W r h B
3,4,5 A
1.2 Totals 2085 1555 1773 1851 7264 M~eg~r 2079 1538 1735 1810 7162 Diff r n 0.3 1.1 2.2 2.3 1.4 c ~
Based upon the change in CBC from ARO to reference bank in and the measured worth of the reference bank, the boron worth at HZP was determined to be -8.29 pcm/ppmB, which was in good agreement with the predicted worth of-8.55 pcm/ppmB.
PTP-3200092 (Revision 1),
Reactor Engineering Power Ascension Program, was reviewed by the inspector, and no questions arose from that review.
Activities performed under this procedure were neither witnessed nor reviewed during this inspection.
No violations or deviations were identified during the inspection of Unit 2, cycle 7 startup activities.
Routine Surveillance of Core Performance for Unit 1, Cycle 11 (61702, 61705)
OSP-64.01 (Revision 3), Reactor Engineering Periodic Tests, Checks, and Calibrations, is an omnibus procedure, applicable to either unit, for performing and documenting required surveillances.
The appendices (and data sheets)
discussed below were performed at different intervals pursuant to the requirements of specific TS.
The dates in brackets are the
time intervals for which the inspector reviewed the individual appendices and data sheets to confirm timely and satisfactory performance of the surveillance requirements.
APPENDIX A (Data Sheet 1):
Periodic Surveillance of Incore Detector System (February 11, 1992
-
May 1,
1992).
The required number of operable detectors was satisfied in all cases.
APPENDIX B
(Data Sheet 2):
Surveillance Requirements for Azimuthal Power Tilt (T ),
(January 7,'992
- June 23, 1992).
The requirements of TS h..2.4 were satisfied in all cases.
APPENDIX C:(Data Sheet 2):
Surveillance Requirements for Total Integrated Peaking Factors, (January 7,
1992
- June 23, 1992).
The requirements of TS 3.2.2 and 3.2.3, were satisfied in all cases.
APPENDIX D (Data Sheet 4):
Calculation of Internal Axial Shape Index, (January 10, 1992
- June 2, 1992)
was acceptable in all six cases reviewed.
APPENDIX E
(Data Sheet 5):
Calculation and Adjustment of Fixed Incore Detector Alarm Setpoints, (January 21, 1992 June 19, 1992)
was acceptable for all six cases reviewed.
APPENDIX F (Data Sheet 6): Power Distribution Comparison with
.,
Design, (January 28, 1992
- June 23, 1992)
was acceptable for all six cases reviewed.
Typically, the RMS deviation was the order of two percent.
APPENDIX G (Data Sheet 7):
Reactivity Deviation from Design, (January 14, 1992
- June 10, 1992)
was acceptable for all six cases reviewed.
The greatest and most recent reactivity deviation-was
+168 pcm.
No violations or deviations were identified in the review of
these routine core surveillance activities.
Unit 2, Cycle 6 Measurementd of the Moderator Temperature Coefficient at Power (61708)'P-3200051 (Revisions 7/8),
At Power Determination of Moderator Temperature Coefficient and Power Coefficient, was performed on June 1,
1991, with RCS CBC at 782 ppmB; and on January 6, 1992, with RCS CBC at 283 ppmB.
Both measurements were satisfactory.
, For the latter, the predicted MTC was-19.5 pcm/'F, and the measured value was -17.9 pcm/'F.
The minimum value allowed by TS is -27 pcm/'F.
No violations or deviations were identifie '0 5.
Exit Interview The inspection scope and findings were summarized on June 26, 1992, with those persons identified in paragraph 1 above.
The inspector described the areas inspected and discussed in detail the inspection findings.
No dissenting comments were received form the licensee.
Proprietary materials were provided to and reviewed by the inspector during this inspection, but are not incorporated into this report.
inverse multiplication (initial countrate/
countrate)
administrative procedure, critical boron concentration control element assembly digital reactivity computer debris resistant fuel assembly effective full power day effective full power hour isothermal temperature coefficient lower electrical limit moderator temperature coef ficient USNRC Office of Nuclear Reactor Regulation nuclear steam supply system operating procedure operations surveillance procedure plant change and modification percent millirho (reactivity)
parts per million boron preoperation test procedure reactor coolant system reactor engineering departmental instruction root mean square upper electrical limit AP CBC CEA DRC DRFA e
EFPD NSSS OP OSP PC/M pcm ppmB PTP RCS REDI UEL 6.
= Acronyms and Initialisms Used in This Report 1/M later