ML18228A458
| ML18228A458 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 09/26/1978 |
| From: | Robert E. Uhrig Florida Power & Light Co |
| To: | Stello V Office of Nuclear Reactor Regulation |
| References | |
| Download: ML18228A458 (12) | |
Text
REGULATORY 1NFORMATIGN D1STRIBUTION SYSTEM (BIDS>
DlSTRIBUTXGN FOR INCOMlNG MATERIAL 50-P REC:
STELLO V NRC ORG'.
UHRIG R E FL PWR 5 LIGllT OCDATE: 09/26/78 DATE RCVD: 10/03/78 DOCTYPE:
LETTER NOTARIZED:
YES COPIES RECEIVED
SUBJECT:
LTR 3 ENCL 40'EQUESTING EXTENSION FOR AUTHORIZATXON TO CONT1NUE OPERATION OF UNIT 3 FOR AN ADDL 4 EQUIVALENT MONTH.
XNSTEAD OF PROCEEDING WITH SUBJECT FACILITY"S STEAM GENERATOR INSPEC DURING THE MGNTf-I OF OCT 1978 BEGINING OCT 17 1978...
W/ATT
-rc, %xone~
oF Aupwoggggy oPug~)46 lufeet/Ac,.
REVIEWER INITIAL:
XJM DISTRIBUTOR INITIAL:
DISTRIBUTION OF Tl-IIS MATERIAL IS AS FOLLOWS PLANT NAME: TURKEY PT 3)3 GENERAL DISTRIBUTION FOR AFTER ISSUANCE OF OPERATING LICEN E.
(DISTRIBUTION CODE AOOi)
FOR ACTION:
INTERNAL:
EXTERNAL:
BR CllIEF ORB3>i BC>'~W/7 ENCL REG FILF>> rW/ENCL
. IJ/2 ENCL HANAUER+>W/ENCL AD FGR SYS Sc PROJ~4W/ENCL REACTOR SAFETY BR4I~W/ENCL EEB~~W/ENCL J
MCGGUGH+4lW/ENCL LPDR'S MIAMI, FL~~W/ENCL TERA+4W/ENCL NSI C~~~l J/ENCL ACRS CAT B<.@W/16 ENCL NRC PDR4l+W/ENCL OELD44LTR ONLY CORE PERFORMANCE BRwwW/ENCL ENGINEERING BR++W/ENCL PLANT SYSTEMS BR>+W/ENCL EFFLUENT TREAT SYS+<IJ/ENCL DISTRIBUTION:
LTR 40 ENCL 39 S 1 ZE:
2P+4P CONTROL NBR:
781570210 9$ %%%8fÃ9%%%%8/%%%3/
3I %4%%%+5+%%%%%%%%%%
Tl IE END
%%%%%%%%%3f 3l%%%%%%%%%%%%%%4+%%%>%4<
, lt t'i'1 v
~
~ I y
i,'I I
P. O. BOX 013100. MIAMI, FL 33101 yy9llygi
+lPtvv4%
FLORIDAPOWER & LIGHTCOMPANY September 26, 1978 L-78-312 r
Office of Nuclear Reactor Regulation Attn:
Mr. Victor Stello, Director Division of Operating Reactors U.
S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Mr. Stello:
Pl
~PI AO Pl~
CO~
~5B Re:
Turkey Point. Unit 3 Docket No. 50-250 Proposed Amendment to Operating License DPR-31 Turkey Point Unit 3 is required by operating license DPR-31 to be shutdown for a steam generator inspection during the month of October. 's you know, steam generator inspections involve significant costs to our customers because of the differential costs of the fuel which must be consumed to generate replacement power for the unit.
The inspection also involves considerable exposure to our workers.
For these
-reasons it is important to perform only those inspections necessary'o ensure safe and efficient operation.
The attached analysis concludes that Turkey Point Unit 3 can safely be operated for an additional four equivalent months of operation.
We believe that this analysis is conservative and provides an adequate basis for an additional four months of operation prior to performing a steam generator reinspection.
We have concluded that our operating experience subsequent to the steam generator inspection completed in February
- 1978, does not justify a steam generator inspection prior to t:he next refueling outage.
The next refueling outage for Unit 3 is scheduled to begin in early January 1979.
There has been one shutdown of PTP3 as a result of a tube leak since the last inspection.
We have also had indications of a very slight primary to secondary leak for approximately the last week in that short lived radio-nuclides have been detected at the air ejector exhaust.
This extremely small leak is less than the minimum threshold for leak rate determination.
IIPglgWP tIIllXHRKt'OI'7, 57 PEOPLE... SERVING PEOPLE
Mr. Victor Stello September Page Two This amendment request has been reviewed by the Turkey Point Plant Nuclear Safety Committee and the Florida Power 6 Light Company Nuclear Review Board.
They have concluded that operation of Unit 3 in accordance with this amendment will continue to ensure that the health and safety of the public is protected.
We request 'that you respond to this request as soon as possible.
Our existing operating license requires us to shutdown Unit 3 by October l7, 1978 for a steam generator inspection.
System considerations will require us to shutdown by October 9, unless we are assured that this request will be granted.
We would be glad to meet with you or your staff to aid you in your review of this request.
Very truly yours, Robert E. Uhrig Vice President Advanced Systems 6 Technology cc:
Robert Lowenstein, Esquire J.
P. O'Reilly, Region II REU/GDW/cf
TURKEY POINT UNIT 3 EXTENSION OF AUTHORIZED OPERATING INTERVAL Turkey Point Unit 3 is presently authorized to operate 8
equivalent operating months beyond the last steam generator inspection outage.
At that inspection, it was determined that flow slot closure had occurred.
Therefore, the current authorized operating interval enables operation to 8
EFPI41 beyond closure.
This analysis evaluates continued operation of Turkey Point Unit 3 for an additional 4 equivalent months (ie.
12 EFP&l beyond, closure).
Turkey Poin't Unit 4 has had 2 S/G re-inspections at points beyond full closure of flow slots (at approximately 5
EFPN and 12 EFPH).
Because'nspection results and operating history have shown that denting is more advanced in Unit 4 than in Unit 3, utilizing these inspection results to predict the condition of Turkey Point Unit 3 wi11 provide con'servative estimates of Unit 3's condition.
The two re-inspections (Unit 4) provided data representing 6
individual S/G conditions (2 inspections, 3 5/G's per inspection).
These 6 inspections were reviewed, and the one with the highest. ratio-of restricted tubes in the tube lane to total unplugged tubes in the tube lane {within the 17 1/2% strain boundary) was selected.
Restricted tubes were de'fined as those which restricted either the
.650,
.610 or
'540 probes.
The most restrictive condition was S/G 4A at 5 EFPH.
129 restricted tubes in the tube lane 227 total unplugged tubes xn the tubelane Then the Unit 3 S/G with the most unplugged tubes (within the 17 3./2% strain boundary at 5
EFPN) was selected.
The result was 171 unplugged tubes in S/G 3A.
Therefore, at the end of 5 EFPll beyond closure for Turkey Point Unit 3, the predicted number of restricted tubes is as follows:
171 un lu ed tubes X 129 restricted tubes 98 restricted 227 unplugged tubes Now looking at Unit 3 after 12 EFPb1 beyond closure, the resulting number of unplugged tubes {within the 17 1/2%
strain boundary) is 320.
Therefore, at the end of 12 EFPM beyond closure, the predicted number of restricted tubes is:
98 restricted tubes X
= 184 restricted tubes 320 171 A very conservative approach is to assume that all of these restricted tubes would develop through wall cracks during a
postulated main steam line break (MSLB) analysis.
As presented in previously submitted analyses, each tube would yield a leakage of less than 0.05 GPM.
Considering the 184 tubes
- above, the estimated increase in leakage is:
184 X 0.05 GPM = 9.2 GPM This added to the 0.3 GPM leakage assumed to be present at the start of the MSLB (which would increase to approximately 0.7 GPM due to the MSLBAP), yields a total leakage of less than 10 GPM.
An analysis has been previously submitted analyzing primary to secondary leakage during a
MSLB assuming a
10 GPM leak rate.
Previous analyses have also established that a
10 GPM leak rate has a negligible effect on primary system thermal hydraulic parameters, the DNB ratio, the percentage of reactor coolant lost by leakage and the time to terminate the core transient during a postulated MSLB accident.
The LOCA effects previously analyzed still apply since these effects are only dependent on the size and number of through wall cracks existing at the time of the accident.
The size and number of cracks are maintained within safe values by the
.3 GPM per steam generator operating limit already imposed.
The effect of secondary to primary leakage during LOCA would be negligible relative to primary system thermal hydraulic parameters when compared to the effects of the LOCA on these parameters.
This analysis supports operation of Turkey Point Unit 3 through 12 EFPM beyond closure of the slots.
The analysis was developed using very conservative assumptions:
ie.
Used Turkey Point Unit 4 inspection results to extrapolate Unit 3 predictions.
The method used to calculate the number of restricted tubes maximized the resulting number of tubes for consideration.
~ ~
V CJ
~
I 4
Assumed that all restricted tubes would.fail during the postulated MSLB.
This includes tubes which restrict the
.650 probe and are not plugged. to justify a 6 month operating interval.
Additionally, Turkey Point Unit 3 will actually operate less than 12 EFPM (approx.
11 EFPM) before a refueling shutdown is required.
Based upon the results of this conservative
- analysis, Florida Power 6 Light Company has concluded that Turkey Point Unit 3 can be safely operated an additional four (4) equivalent operating months beyond the currently authorized eight (8) equivalent operating months.
'>lb
.'eal' ia c
.i.fOI,/
I
~
COUNTY OF DADE STATE OF PLORXDA
)
)
)
ss E. A. Adomat
, heing first duly sworn, deposes and says:
That he is Executive Vice P Light Company, the herein; of.Florida Power 6
That he has executed the foregoing document; that. the state-ments made in this said document are true and correct to the best of his Knowledge, information, and belief, and that he is authorized to execute
.the document on behalf. of said Licensee H. A. Adomat Subscribed and sworn to before me this cg 7 day of.
NOTARY PUBLl in and for the County of Dade, Sta e of Flor a
NOTA/
hJBUC STATC OF FLOtlIDA EE tAINE MY COMMISSION 'XPIAES MARCII 27, 1%@
, Ny CO@i%2.8 8iOn eXPireS Gol'IDED TIIRU MAYNARD doNQING AGENcY Q
~U c
I ~
~ r
,o>>l~~>tlap.
g%l~
s
- ".(.(3 3 7
'ip '
rl.hTQ g P$
'~+ U~
'P l,igg~AA