ML17339A358
| ML17339A358 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 10/29/1979 |
| From: | Schwencer A Office of Nuclear Reactor Regulation |
| To: | Robert E. Uhrig FLORIDA POWER & LIGHT CO. |
| References | |
| NUDOCS 7912050174 | |
| Download: ML17339A358 (13) | |
Text
OCTOBER 2 9 f979 Docket Hos.60-250 and 60-251 Dr. Rabert E. Uhrfg, Yfce President Advanced SystenIs and Technology Florida Pawer and Light Company Post Office Box 529100 HfanIf, Fl orida 33152
Dear Dr. Uhrig:
The staff has recently completed a review of the LER's and Technical Specification requirements, related to the Control Rod Positfan Indication Systems (RPI) at Westinghouse PHRs.
We have determihed
- that, a wide varfa-tfon exfsts fn the number of LERS receival'nd the technical specification requirements and have, therefore, decided to clarify our requirements.
At the time of development of the Standard Technical Specifications, a
systematic attempt was made to clarify potentially ambiguous specifications.
One such specification was the control rod misalignment specification for 3Jestfnghouse-designed reactors.
Westinghouse has performed safety analyses for control rod misalfgnment up to 15 inches or 24 steps (ane step equals 6/8 inch).-
Since analysis of mfsalignments in excess of this amount have not been submitted, we have imposed an LCO restricting continued operation with a misalignment fn excess of 15 inches.
,Because the analog control rod position indication system has an uncertainty of 7.5 inches (12 steps),
when an indicated devfhtfon of 12 steps exists, the actual misalignment may be 16 inches.
This fs because one of the coils, spaced at 3. 75 inches, may be fafled without the operator l;nowfng about it.
The Standard Technical Specifications were written to e'limfnate any confusion about this, and allow a deviation of up to 12 indicated steps.
Surveillance requf rements, on the indicatfan accuracy of 12 steps were also prepared to ensure that the 16 inch LCQ is met.
There is no difference intended fn requirements issued for any Westinghouse reactor.
Hestfnghouse has informed the AC that all of their customers have
~
been informed af this and that all the licensees should be following the same
'rocedures regardless of the language of their Technical Specification.
That
.fs, plants with Technical Specifications written fn terns of 15 inch misalfgn-mer>t should be considering the 12 steP instrument inaccuracy when monitoring rod position.
A related problem fs that the installed analog control rod position indicating system equipment may not, in.some areas, be adequate to maintain the control rod nisalignment specification requirement because of drift problems in the calibration curves.
This fs evidenced by numerous LERl,s concerning rod position indication accuracy.
In these cases the uncertafnt n
be more than 12 OFFICE $."
SURNAME OATEN.
NRC FORM 318 t9 76) NRCM 0240
. 'V.93.3.0.50 AU.S. GOVERNMENT PRINTING OFFICE: 1979.289 389
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Dr. Robert E. Uhrig Florida Power and Lfght Company The present tItestfnghouse Standard Technical Specifications (t<-STS) require all full length control rods to be positioned within +
12 steps pndfcated position) of their group step counter demand position.
Since numerous problemIs have developed in signal conditioning circuits for display indication of control'od posftion, the staff has deter)1>fned Chat the "indicated position" requirement m~I be fulfilled by voltage measurements obtained from the posftfon indication mechanfsrr)
(and therefore no LER need be submitted) provided a sufficient data base has been establfshed to ensure a correlation between voltage and position.
A copy of the current, applicable W-STS Specifications (3/4.1.3.
1 and 3/4. 1.3.2) are attached for your information and consideration.
.It fs requested that you review your present technical specifications to ensure that the control rods are requfred to be maintained within + 12 steps indicated and that'the rod posftfon indication system fs verffied to be accurate to within 12 steps.
If your review indicates that this is not the case, you should so inform the Commission within 30 days of your receipt of this letter together with your plans to correct the deficiencies.
Any needed corrective actions r))ay take several f'orms; such as (1) revising your technical specifications to limit control rod misalfgrIment to no more than + 12 steps indfcated position (2) seeking relief by performing analyses
)ustifyfng (with pena'ftfes if needed) greater misalignments, or (3} proposing alternate or supplemental monitoring speciffcaCions to demonstrate compliance with the + 12 step indicated alignment requirement.
If you have any questions on this matter, please contact us.
Sincerely,
Enclosure:
H-STS Specifications 3/4.1.3.
1, apd 3/4. 'l.3.2 cc:
w/enclosure See next page A. Schwencer, Chief Operating Reactors Branch Ill Division of Operating Reactors OFFICE P DOR:ORB DOR:ORB SURNAME DATE$
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en 79 NRC FORM 3) 8 (9-76) NRCM 02~0
- V.S GOVERNMENT PRINTING OFFICE< 1979.289 369
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UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C.20555 ocToBER.
9 9 i979 Docket Nos.
50-.250 and 50-251 C
I Dr. Robert E. Uhrig, Yice President Advanced Systems and Technology Florida Power and Light Company Post Office Box 529100 Miami, Florida 33152
Dear Dr. Uhrig:
The staff has recently completed a review of the LER's and Technical Specification requi rements related to the Control Rod Position Indication Systems (RPI) at Westinghouse PWRs.
We have determined that a wide varia-tion exists in the number of LERS received and the technical specification requi rements and have, therefore, decided to clarify our requirements.
At the time of development of the Standard Technical Specifications, a
systematic attempt was made to clarify potentially ambiguous specifications.
One such specification was the control rod misalignment specification for Westinghouse-designed reactors.
Westinghouse has performed safety analyses for co'ntrol rod misaIignment up to 15 inches or 24 steps (one step equals 5/8 inch).
Since analysis of misalignments in excess of this amount have not been submitted, we have imposed an LCO restricting continued operation with a misalignment in excess of 15 inches.
Because the analog control rod position indication system has an uncertainty of 7. 5 inches (12 steps),
when an indicated deviation of 12 steps exists, the actual misalignment may be 15 inches.
This is because one of the coils, spaced at 3. 75 inches, may be failed without the operator knowing about it.
The Standard Technical Specifications were written to eliminate any confusion about this, and allow a deviation of up to 12 indicated steps.
Surveillance requirements, on the indication accuracy of 12 steps were also prepared to ensure that the 15 inch LCO is met.
There is no difference intended in requirements issued for any Westinghouse reactor.
Westinghouse has informed the NRC that all of their customers have been informed of this and that all the licensees should be following the same procedures regardless of the language of their Technical Specification.
That is, plants with Technical Specifications written in terms of 15 inch misalign-ment should be considering the 12 step instrument inaccuracy when monitoring rod position.
A related problem is that the installed analog control rod position indicating system equipment may not, in some areas, be adequate to maintain the control rod misalignment specification requirement because of drift problems in the calibration curves.
This is evidenced by numerous LER',s concerning rod position indication accuracy.
In these
- cases, the uncertainty may be more than 12 steps.
Dr. Robert E. Uhrig Florida Power and Light Company 2
OCTOBER 2 9 197~
The Present Westinghouse Standard Technical Specifications (W-STS) require all full length control rods to be positioned within +
12 steps /indicated position of their group step counter demand position.
Since numerous problems have developed in signal conditioning circuits for display indication of control rod position, the staff has determined that the,"indicated position" requirement.
may be fulfilled by voltage measurements obtained from the position indication mechanism (and therefore no LER need be submitted) provided a sufficient data bas'e has been established to ensure a correlation between voltage and position.
A copy of the current, applicable W-STS Specifications (3/4. 1.3. I and 3/4. 1.3.2) are attached for your information and consideration; It is requested that you review your present technical specifications to ensure that the control rods are required to be maintained within + 12 steps indicated and that the rod position indication system is verified to be accurate to within 12 steps.
If your review i ndicates that this is not the case, you should so inform the Commission within 30 days of your receipt of this letter together with your plans to correct the deficiencies.
Any needed.corrective actions may take several. forms; such as (1) revising your technical specifications to limit control rod misalignment to no more than
+ 12 steps indicated position, (2) seeking relief by performing analyses Justifying (with penalties if'eeded) greater misalignments, or (3) proposing alternate or supplementa'l monitoring specifications to demonstrate compliance with the + 12 step indicated alignment requi rement.
If you have any questions on this matter, please contact us.
Sincerely A. Schwencer, Chief Operating Reactors Branch gl Division of Operating Reactors
Enclosure:
W-STS Specifications 3/4. 1.3.
1 and 3/4. 1.3. 2 cc:
w/enclosure See next page
Robert E. Uhrig Florida Power and Light Company OCTOBER 2
9 579 cc:
Mr. Robert Lowenstein, Esquire Lowenstein,
- Newman, Reis and Axelrad 1025 Connecticut Avenue, N.W.
Suite 1214 Washington, 0.
C.
20036 Environmental and Urban Affairs Library Florida International University Miami, Florida 33199
'I Mr. Norman A. Coll, Esquire
'teel, Hector and Oavis 1400 Southeast First National Bank Building
- Miami, Florida, 33131 Mr. Henry Yaeger, Plant Manager Turkey Point Plant Florida Power and Light Company P. 0.
Box 013100 Miami, Florida 33101 Mr. Jack Shreve Office of the Public Counsel Room 4, Holland Building Tallahassee, Florida 32304
REACTIVITY CONTROL SYSTEMS 3/4. 1. 3 MOVABLE CONTROL ASSEMBLIES GROUP HEIGHT LIMITING CONDITION FOR OPERATION 3.1.3.1 All full length (shutdown and control) rods, and all part length rods which are inserted in'he core, shall be OPERABLE and positioned within a 12 steps (indicated position)'f. their group step counter demand position.
APPLICABILITY:
MODES 1" and 2" ACTION:
Mith one or. more full length rods inoperable due to being. immovable as a result of excessive friction or mechanical interference or known to be untrippable, determine that the SHUTDOMN MARGIN require-ment of Specifi"ation 3.1.1.1 is satisfied within 1
hour and be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
b.
C.
Mith more:than one full or part length rod inoperable or misaligned
~ from the group step counter demand position by more than
+ 12 steps (indicated position),
be in HOT STANDBY within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.
With one full or part length rod inoperable due to causes other than addressed
'by ACTION a,
- above, or misaligned from its group step
'ounter demand height by more than
+ 12 steps (indicated position),
POWER OPERATION may continue provided that within one hour either:
1.
The rod is restored to OPERABLE status within the above alignm'ent requirements, or 2.
The rod is declared inoperable and the SHUTDOWN MARGIN requirement'f Specification 3. l. l. 1 is satisfied.
POWER OPERATION may then continue provided that:
a)
A reevaluation of. each accident analysis of Table 3. 1-1 is performed within 5 days; this reevaluation shall confirm that the previously analyzed results of these accidents remain valid for the duration of operation under these conditions')
The SHUTDOWN MARGIN requirement of Specification
- 3. 1. 1. 1 is determined at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
"See Special Test Exceptions
- 3. 10.2 and
- 3. 10. 3.
M-STS 3/4 1-14 OCT g
go-.s
I
REACTIVITY CONTROL SYSTEMS LIMITING CONDITION FOR OPERATION (Continued) c)
A power distribution map.is obtained from the movable incore detectors and F (Z) and F
H are verified to be within their limits within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
d) fither the THERMAL POWER level is reduced to less than or equal'o 75K of RATED THERMAL POWER within one hour and within the next 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> the high neutron flux trip setpoint is reduced to less than or equal to 85% of RATED THERMAL POWER, or
'e)
The remainder of the rods in the group with the inoperable rod are aligned to within +
12 steps of the inoperable rod
.within one hour while maintaining the rod sequence and insertion limits of Figures (3. 1-1) and (3. 1-2); the THERMAL POWER level shall be restricted pursuant to Speci-fication (3. 1.3.6) during subsequent operation.
SURVEILLANCE RE UIREMENTS
- 4. I. 3. 1.
1 The position of each full and part length rod shall be determined to be within the group demand limit by verifying the individual rod positions at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> except during time intervals when the Rod Position Deviation Monitor is inoperable, then verify the group positions at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
4.1.3.1.2 Each full length rod not fully inserted and each part length rod
'hich is inserted in the core shall be determined to be OPERABLE by movement
.of at least 10 steps in any one direction at least once per 31 days.
W-STS 3/4 1" 15
~'ABLE
- 3. 1-1 ACCIDENT ANALYSES RE UIRING REEVALUATION IN THE EVENT OF AN INOPERABLE FULL OR PAPT LENGTH R00
'I Rod Cluster Control Assembly Insertion Characteristics Rod Cluster Control Assembly Misalignment Loss Of Reactor Coolant From Small Ruptured Pipes Or From Cracks In Large Pipes Which Actuates The Emergency Core Cooling System Single Rod Cluster Control Assembly Withdrawal At Full Power Major Reactor Coolant System Pipe Ruptures (Loss Of Coolant Accident)
Major Secondary System Pipe Rupture Rupture of a Control Rod Drive Mechanism Housing (Rod Clus er Control Ass'embly Ejection)
W-STS 3/4 I"16 OCT 1
576
POSITION INDICATION SYSTEMS-OPERATING LIMITING CONDITION FOR, OPERATION 3.1.3.2 The shutdown, control and part length control rod position indication system and the demand position indication system shall be OPERABLE and capable of determining the control rod positions within k 12 steps.
APPLICABILITY:
MODES 1'nd 2.
ACTION:
a.
b.
With 'a maximum of one rod position indicator per bank inoperable either'.
l.
Determine the position of the non-indicating rod(s) indirectly by the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and immediately after any motion of the non-indicating rod which exceeds 24 steps in one direction since the last determination of the rod's position, or 2.
Reduce THERMAL POWER TO less than 50K of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />'ith a maximum of one demand position indicator per bank inoperable either:
l.
Verify that all rod position indicators for the affected bank are OPERABLE and that the most withdrawn rod and the least withdrawn rod of the bank are within a maximum of l2 steps of each other at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, or 2.
Reduce THERMAL POWER to less than 50K of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
SURVEILLANCE'RE UIREMENTS F 1.3.2 Each rod position indicator shall be determined to be OPERABLE by
.verifying that the demand position indication system and the rod position indication system agree within 12 steps at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> except during time intervals when the Rod Position Deviation Monitor is. inoperable, then compare the demand position indication system and the rod position indica-tion system at least once per 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.
W-STS 3/4 1"17
k 0