ML20073A092
| ML20073A092 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 04/06/1983 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8304110656 | |
| Download: ML20073A092 (12) | |
Text
c TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II April 6, 1983 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555
Dear Mr. Denton:
In the Matter of the
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Docket Nos. 50-259 Tennessee Valley Authority
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50-260 50-296 By letter from D. B. Vassallo to H. G. Parris dated January 17, 1983, we received a request for additional information regseding the proposed inservice pamp and valve testing program for the Browns Ferry Nuclear Plant. Encioned is our response to that request.
After NRC approval of tne enclosed resp:nses and resolution of any remaining item, the program will be revised and resubmitted.
In cur response to item 1 we are formally requesting an exemption to the requirements of 10 CFR Part 50.55a re.garding interval for $nservice testing. In that request we propose to have implementation of the Inservice Pump and Valve Testing Program for the three units of Browns Ferry on a concurrent interval, as opposed to a separate interval for each unit. The proposed start date of the 10-year interval is August 31, 1982, with a corresponding interval ending date of August 31, 1992. This approach was used for the Browns Ferry Section XI Inservice Inspection Program, and to our understanding was accepted by NRC. Additional discussion is provided in our response to item 1.
This latest round of questions from the NRC on the Browns Ferry Section and Valve Test Program greatly concerns TVA. The May 26 and 27, 1982 Section XI meeting at Browns Ferry was held for the purpose of updating the program and resolving any items that the NRC wished to address. TVA recognized the need for the meeting in light of unsuccessful attempts over the past few years to get the NRC to address and approve the Pump and Valve Test Program. Hence, a well prepared, comprehensive program submittal was presented and discussed at length with the NRC representatives in attendance:
E. H. Girard of Region II, R. J. Clark of NRR, and Gerald Paulk, Resident NRC Inspector. TVA representatives left the meeting with the conviction that all of the concerns of the Section XI program had been addressed and resolved to the NRC's satisfaction, and that the program would be approved in a timely manner.
We were disturbed with this request for additional information, since 8304110656 830406 PDR ADOCK 05000259 P
PDR An Equal Opportunity Employer
. Mr. Harold R. Denton April 6, 1983 nearly all of this information was discussed with the NRC in the May 1982 meeting. Furthermore, we are also concerned, despite efforts at the May 1982 meeting and earlier submittals, as to when the Browns Ferry Section XI Pump and Valve Program will be approved in light of the continual questions that we have received.
The NRC apparently recognizes the need for some continuity in the Section XI program requirements as evidenced by its approval of a 10-year versus a three-year program update requirement. Yet, almost halfway through the first inspection interval, as determined by 10 CFR 50.55a(g), Browns Ferry still does not have an approved program. At some point the criteria against which our program submittal is being reviewed must be fixed. Perpetuation of unresolved issues, as has been the case for the past several years, creates problems in complying with both the technical specifications and the Section XI requirements. It keeps the surveillance program in an unncessary state of continual alteratior. and adds 2onfusion to an alrecdf complex program, thus providing increased epportunity for violation of either or both sets of requirements. We trust that HRC will continue their review efforts and approve the subject plan in the near future.
Very truly yours, TENNESSEE VA1. LEY AUTHORITY I
L. M.' Mil's, M ager Nuclear Licensing Subscribeg d sworn to befor l
me this U day of
- 1983 Notary Public My Commission Expires Enclosure j
cc:
See page 3 l
i
. Mr. Harold R. Denton April 6,1983 cc (Enclosure):
U.S. Nuclear Regulatory Commission Region II ATTN: James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303 Mr. R. J. Clark Browns Ferry Project Manager U.S. Nuclear Regulatory Commission 7920 Norfolk Avenue Bethesda, Maryland 20814 Mr. E. H. Girard U.S. Nuclear Regulatory Commission Region 11 101 Marietta Street, NW, Suite 2900 At,lanta, Georgia 3G303 r
ENCLOSURE RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION INSERVICE PUNP AND VALVE TESTING PROGRAM BROWNS FERRY NU(LEAR PLANT UNITS 1, 2, AND 3
(
Reference:
NRC Letter f rom D. B. Vassallo to H. G. Parris dated January 17, 1983) 1.
NRC Question The progran states that it will be applicable until September 1988.
Explain t' e basis for extending the program to that date.
TVA Response In response to this question TVA hereby requests an exemption f rom the requirements of 10 CFR 50.55a to allow concurrent interval start and end dates for the Inservice Panp and Valve Testing Program of the Browns Ferry Nuclear Plant units 1, 2, and 3.
The start date for the interval is proposed to be August 31, 1982, the submittal date of the revised Browns Ferry Pump and Valve Te st Program. That revired program was updated in accordance with the 1980 edition, winter 1980 sddenda of Section II.
Such a concurrent interval essentially integrates three separate programs (oce for each unit) into one program for all three units. The proposed end date I
of the interval would be August 31, 1992, 120 months from program l
subnittal. Discussion of the benefits to both TVA sud the NRC staf f of following such a program with coscertent interval stcrt dates wa? made in TVA letters, L. W. Mills to T. A. Ippolito dated July 11,1979 and December 24, 1989.
In establishing and proposing a concurrent program for the three units, w have been caref ul to perf oon certsin reviews to ensure required elements are included. A thorough review of the program has been perferned to ensure that any differences betwen each unit's listing of safety-related pumps and valves have been noted in the current program, and that the applicable testing procedures reflect those differences.
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Furthermore, we have been careful to ensure that establishing a concurrent or integrated program and revising the inservice testing interval date will not in any way impact the current testing schedules of the individual valves. For instance, main steam relief valves which have a 60-month test frequency interval, will continue to be tested in accordance with current 60-month interval already established. A new 60-month testing interval will not be started to coincide with the L agust 31, 1982 program interval.
l Therefore, no valve test interval will exceed 60 months since previously tested because of a revised program interval date. The Browns Ferry program will be revised to state that the current program is applicable to August 31, 1992 upon concurrence f rom the NRC.
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. 2.
NRC Question The Brookhaven National Laboratory reviews of your previous inservice testing (IST) programs, as documented in reports BNL-NUREG - 26617 and
-265 83, will, in part, provide a basis for the NRC's safety evaluation of your IST program.
A.
For valves that were included in the IST programs reviewed by Brookhaven, but which are not included in your new IST program, it is requested that you submit the basis for the deletions.
B.
For any instances where your new IST program proposes a reduction of testing requirements (including test f requencies), other than those attributal to the use of the 1980 code, it is requested that you submit the basis for the changes.
TVA Response Ito currert program was developed f ram the Brookhaven National Laboratory i
review of the previous prograu addressed during the May 26 and 27,1982 meeting at Erosas Ferry betweca NRC sad TVA representatives. The basis for the changes between the previous and the current programs as given below were addressed and discussed at length during this meeting.
A.
Valves omitted in the Ic. test program submittal:
1 i
Psin steen lire drain valves 1-35, 56: These valves are conttienent
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isolatton VLives that do not change position upon a containment isolatica signal. These type valves are tested in accordarce with l
Appendix J and are included in the ' valves to be leak-rate tested' table, Attachment 3 of the latest submittal. These valves do not have operability requirements in accordance with the 1978 NRC staff guidance j
letter; hence, they were deleted.
RER crosstie valve 74-46: This valve performs no safety function; it has power removed so that it cannot be operated. Hence, this valve is deleted from the program.
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. I B.
Reduction in testing requirements from previous to latest submittal:
j Feedwater check valves 3-554, 3-558, 3-568, 3-572: The basis for reducing the frequency of test for these valves is addressed in relief request PV-8.
i Standby liquid control check valves63-525, 63-526: See relief request PV-8.
Reactor recirculation system check valves68-508, 68-523,68-550, 68-555: See relief request PV-8.
Reactor water cleanup check valves69-579, 69-624:
See relief request PV-8.
Residual heat removal check valves74-661, 74-662:
See relief request PV-8.
Recirculation loop flow control valves 43.'s, 68-79:
The testing frequency se stated in the previous tuomittal for these valves was charged f rom qu:.rteriv 40 every colu shutdovn in the letest submittal.
It is not r easible to test these valves during power operr tion sinco this would require isolatien of one terirculation loop and a teduction in power level. Ther.e valves have 61 ways been tested every cold shutdcwn per IWV-3412, so the previous sutaittal was in error to state the frequency as quartesly.
Reactor cces isolation caoling valse 71-37: The testing fraquency for this valve was changed from gostterly to every cold shutdown.
If this valve f ailed closed during an operability test, the system would be rendered inoperable. Since this is a convenience valve that performs no active safety function, the risk of f ailure during operability testing is not warranted.
High pressure coolant inj ection valve 73-34:
Same as RCIC valve 71-37.
3.
NRC Question Why doesn't your program specify valve position indication checks in accordance with IVV-33007 TVA Response As stated at the May 1982 meeting, Browns Ferry is in compliance with IWV-3300 by checking valve position indications it S.I.3.2.10.
The program will be revised to include valve position indication checks.
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NRC Question Your IST program relief request PV-1 request s, in part relief from requirement s f or bearing temperature mesurements on your RHR, Core Spray, SLC, and RHRSW pumps. You state that the bearings of thesr4 pumps are lubricated by water supplied by the pumps themselves and that
' satisfactory pump operation is indicative of sufficient bearing lubrication.'
It is our understanding that the intent of the code in requiring bearing temperature measurements was to assure detection and correction of changes in bearing performance while the pumps are still capable of satisfactory operation. This being the case, your basis for relief appears faulty. Provide additional details.
Do you propose any alternate test to replace bearing temperature measurement?
TVA Response Article ITP-4310 states that the temperature of centrifugal pump bearings outside the main flow path of the pump shall be me6sured. Since the water-cooled bearings of the RHR, core spray, and EURSW pumps listed in FV-1 are within the main flow pa th, temperatures are not required to be monitored by the code. The SLC pumps are positive displacement ramps and are not required to have bearing temperatures monitored in accordance with IWP-4310. Vibration measurements are taken on all cf the Section II pumps to ensure detection and corroction of changes in bearing performance while. the pumps are still capable of satisfactory operation. This will be indicated on PV-1 un der
- al t erna t e t e s t r e tho d. '
5.
NRC Guestion Your new IST program shows differential pressure being measured for the SLC pump. Is this correct?
TVA Response
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Since the acceptable
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pump discharge pressure is 1,150 psi, it is clear that any inlet l
pressure deviation has a negligible eff ect on diff erential pressure l
developed by the pump. Hence, discharge pressure is an acceptable parameter to monitor pump performance.
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6.
NRC Question For your new IST program relief request PV-2 submit your specific controls on inlet head.
TVA Response The SLC pump flow test S.I.4.4.A.1. specifies that a minimum level of five-inch H O must be maintained in the suction test tank of the SLC pumps.
2 This ensures adequate, inlet head on the pumps. As stated in PV-2, a caution notice has been incorporated into S.I.4.4.A.1. to maincain this
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minimum level.
7.
NRC Question i
For relief request PV-3 in your new IST program A.
Why do you now state that 'the pumps are tested by circulating liquid to a tank f or,2,_3.i_ nut est'; whereas, in a similar request for relief submitted in your letter of March 3,1979 (Request for Rollaf 52), you indicated that yoa wculd circulate liquid to the tank for 3 minutes during such a test?
B.
At what point in the test do yon considee that the data you are obtaining is stabic? I'rovide data to verify stability af ter two minutes.
TVA Response A.
The change f rom three minutes to twc minutes for the duration of the SLC flow test was made to ensure that the SLC test tank was not pumped dry. The SLC test tank has a limited capacity such that, at its normal flow rat e, the tank is close to being pumped dry af ter three minutes.
B.
As stated in PV-3, a 15-minute f unctional test which involves recirculating water back to the test tank is performed before running the t<wo-minute fl ow test. The 15-minute test is of sufficient length
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for all parameters to stabilize; the two-minute flow test is run immediately afterward. This method of testing was discussed and considered acceptable by the TVA and NRC representatives at the May 1982 meeting.
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. 8.
NRC Question Request for relief PV-4 in your new IST program is somewhat uncicar.
Verify that A.
The person who performs the test has the authority to and will immediately review the test values and determine whether they f all in the required action range of the code (ASME Section XI)
B.
When the above review identifies test values in the required action range, the related pump or pumps will immediately be declared inoperative and not returned to service until the cause of the deviation has been determined and corrected.
TVA Respons_e A.
The Section XI flow tests are performed by the unit ' operators or plant assistant unit operators under the guidance cf the unit operator.
The uni t operator or the shif t technical advisor will immediately review the flow test paraveters and determire whet 1:er the parsmeters fall within the required action range cf the ocde.
B.
Following the guidelines set forth in the March 17, 1980 NuC memorardum from Samuel E. Byron to R. C. Lewis, as soon as the ponp flow test data is recognized as being withis the required action range the pump is declared inoperable. This practice will he-incorpcrated ittc the ficw test Surveillance lastruc tions (5.I. 's).
I 9.
NRC Question Your relief request PV-5 proposes alternative testing requirements.
Provide specific details of the alternative test cammitment including 1
Background information on the atlernative testing justifying its usefulness.
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A description of the alternate test procedures, including allowable
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ranges of test values and their bases.
TVA Resconse The alternate test method (equipment diagnostics) utilizes more measurement points than required in IWP-4510. Al so, in conjunction with the displacement readings, peak velocity readings are taken and the data points are plotted on trend curves. The equipment diagnostics program has proven
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. more reliable in identifying and defining vibration problems in CSSC systems than the Section II program. A specific exemple would be the identification of structural resonances associated with 12 EBRSW EECW pumps which had not been detected by previous testing in accordance with IWP-4510. The peak velocity limits (less than 0.64 in/sec) were established using instrument manuf acturers' information and industry experience. The limits are subject to change as acre test data becomes available.
10.
NRC Question Relative to your relief request PV-6 Verify that you are only requesting relief from the portions of IWV-3417 and IWV-3523 that state 'when corrective action is required a s a result.of tests during cold shutdown, the condition shall be corrected before startup.'
Shouldn't the statement given under the heading ' Al t er na t ive Testing' be part of ycur ' Basis for Eclief ?'
It does not propose an alternate test.
TVA Resconse Relief request PV-6 addresses articles IWV-3417(b) and I#V-3523 portions MLich state, 'when corrective action is required as a rescit of tests made during cold shutdown, the condition shall be corrected tefore startup. '
Yes, the statement under the heading ' Alternate Testing' should be part of the ' Basis for Relief. '
11.
NRC Question Relative to your relief request PV-7 I
l Are there valves located in the lines with the CHD scram function valves which, if closed, would permit test'ing of the scram function l,
valves without scramming the control rods?
Could not symetrically opposed valves be tested simultaneously in l
pairs during operation without resulting in any requirement for significant fuel preconditioning?
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The scram discharge valves of symmetrically opposed control rods could not be tested without requiring significant fuel preconditioning. We believe the current testing program outlined in relief request PV-7 is adequate.
12.
NRC Question For the valves addressed in relief request PV-8 Why do you propose to tert the valves only each refueling outage rather than at each cold shutdown?
r Do the subject valves have permissible leakage rater specified in accordance with IWV-34267 Will analysis of leakage rates r.nd corrective action be undertaken for the subject valves in accordance with IWV-3425 and IWV-3426, re spe ctiv ely ?
TTA Response As discussed in the May 1982 meeting, these are poorly accessible check valves that are difficult to test. Testing these valves creates unf avorable conditicns for the unit and test personnel. These difficulties were discussed at length in the May 1982 meeting. As agreed upon by attending NRC representatives, these valves will be tested during each refueling outage rather than at cold shutdowns.
IWV-3426 requires leakage rates to be specified by. the plant owner. The leakage rates for these valves are specified in accordance with 10 CFR 50, Appendix J by the plant owner.
Analysis of leakage rates and corrective action is undertaken for the subject valves in accordance with 10 CFR 50, Appendix J, to satisfy overall leak rate criteria f or primary containment.
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13.
NRC Ouestion Cannot the valves addressed in relief request PV-9 be partial-stroke exercised quarterly?
TVA Response As stated in PV-9 and the May 1982 review meeting, these valves cannot be exercised without introducing torus water into the vessel.
14.
NRC Question Guidance provided to you by the NRC in a letter dated January 13, 1978 stated that your IST program should include all safety related valves.
It appears that you do not include all saf ety related valves in your program. For example, you do not include valves in the diesel generator fuel oil transfer lincs or in the diesel generator starting air system. Why are such items not included in your program?
TVA Response It has always been the position of TVA that the scope at the Section XI pump and valve test program, prepared f or Browns Ferry in accordance with NRC guidelines at the time of program submittal, only includes those valves I
that are in water, steam, or radioactive we ste type systems. The reasoning for this being the basis f or TVA's original submittal for Browns Ferry was i
discussed by NRC representativas at the May 1982 review meeting and was agreed to be applicable to the latest progran submittal. The f act that the Program submitted does not satisfy subsequent NRC recoamendations or NRC recommendations that were, and apparently still are, in contention at the time of the submittal is not sun, rising. While TVA understands the difficulty of auditing a program submittal several years af ter the date of submission, we do not understand why the May 1982 meeting, which was to resolve such difficulties, was not nearly as successful as it originally appeared.
If the NRC no longer agrees with decisions reached before and during the May 1982 meeting, please provide approved NRC position documnntation that specify otherwise.
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