ML19305D392
| ML19305D392 | |
| Person / Time | |
|---|---|
| Site: | Big Rock Point File:Consumers Energy icon.png |
| Issue date: | 02/29/1980 |
| From: | Fehringer J, Rockhold H EG&G, INC. |
| To: | Nerses V Office of Nuclear Reactor Regulation |
| References | |
| CON-FIN-A-6258 EGG-EA-5099, NUDOCS 8004150025 | |
| Download: ML19305D392 (37) | |
Text
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Idsho. inc.
FOmu EG4G-396 INTERIM REPORT Accession No.
Report No.
EGG-EA-5099 C ntract Program or Project
Title:
Systems Engineering Support Subject of this Document:
Safety Evaluation Report, Inservice Testing Program, Big Rock Point - Docket No. 50-155 Type of Document:
Safety Evaluation Report Author (s):
J. M. Fehringer, H. C. Rockhold D:te of Document:
February 1980 R:sponsible NRC Individual and NRC Office or Division:
Victor Nerses, NRC-DOR This document was prepared primarily for preliminary orinternal use. it has not received full review and approval. Since there may be substantive changes, this document should not be considered final.
EG&G Idaho, Inc.
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Idaho Falls, Idaho 83401 H.'P. Pearson, Supervisor
," Information Processing Prepared for the U.S. Nuclear Regulatory Commission and the U.S. Department of Energy Idaho Operations Office Under contract No. EY-76-C-07-1570 NRC FIN No.
A6258 INTERIM REPC.~..
\\ RC Ressarch and "echnica Assistance Remd scouso075
EGG-EA-5099 February 1983 SAFETY EVALUATION REPORT, INSERVICE TESTING PROGRAM, BIG ROCK POINT - DOCKET NO. 50-155 i
J. M. Fehringer H. C. Rockhold 1
U.S. Department of Energy l
Idaho Operations Office
- Idaho National Engineering Laboratory
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.g This is an informal report intended for use as a preliminary or working document llc ReSearch anc Technical N
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FORM EG&G 396 m... s i n, INTERIM REPORT Accession No.
Report No. EGG-EA-5099
- C ntract Program or Project
Title:
I Systems Engineering Support Subject of this Document:
Safety Evaluation of the Inservice Testing Program for Pumps and Valves at the Big Rock Point (Docket No. 50-155) for the Period 9-1-78 through 5-31-80 Type of Document:
Safety Evaluation Report Author (s):
J. M. Fehringer H. C. Rockhold D:le of Document:
February 1980 R:sponsible NRC individual and NRC Office or Division:
Victor Nerses, NRC-DOR This document was prepared primarily for preliminary or internal use. it has not received full review and approval. Since there may be substantive changes, this document should not be considered final.
EG&G ldaho, Inc.
Idaho Falls, Idaho 83415 Prepared for the l
U.S. Nuclear Regulatory Commission Washington, D.C.
Under DOE Contract No. DE-AC07 761D01570 NRC FIN No. A6258 INTERIM REPORT
C TABLE OF CONTENTS Page I.
Introduction.......................
'l II.
Pump Testing Program...................
2 III. Valve Testing Program 8
1 IV. Attachment I....................... 30 V.
Attachment II
.........'............. 31 i
VI. Attachment III...................... 35 i
t VII. Attachment IV 36
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I.
Introduction Contained herein is a safety evaluation of the pump and valve inservice testing (IST) program submitted by the Comsumers Power Company on 2-1-79 for its Big Rock Point nuclear plant.
The program applies to Big Rock Point for the period 9-1-78 through 5-31-80.
The working session with Big Rock Point and Consumers Power representatives was conducted on 5-16-79 and 5-17-79.
The licensee re-submittal was issued on 12-7-79 and was reviewed by EG&G Idaho Inc., to verify compliance of proposed tests of safety related class 1, 2, and 3 pumps and valves with requirements of the ASME Boiler and Pressure Vessel Code,Section XI, 1974 Edition, through the Summer of 1975 Addenda.
Consumers Power Company has also requested relief from the ASME Code from testing specified pumps and valves because of practical reasons.
These requests have been evaluated individually to determine whether they have significant risk implications and whether the tests, as required, are indeed impractical.
The evaluation of the pump testing program and relief requests for pumps is contained in Section II below; the evaluation of the valve testing program and associated relief requests is contained in Section III. All evalutions for Sections II and III are the recomendations of EG&G Idaho,Inc.
Appendix J exemption requests for category A valves currently being reviewed by the NRC are contained in Attachment I.
Category A, B, and C valves that meet the requirements of the ASME Code Section XI and are not exercised every 3 months are contained in Attachment II.
A listing of P&ID's used for this review are contained in Attachment III.
UC lesearch and Tehia N ASSiStanCO RSp0E 1
Valves that are never' full stroke exercised or that have a testing interval greater than each refueling outage and relief requests with insufficient technical basis where relief is not recommended are summarized in Attachment IV.
II. Pump Testing Program The IST program submitted by Consumers Power Company was examined to verify that Class 1, 2, and 3. safety related pumps were included in the program and that those pumps are subjected to the periodic tests as required by the ASME Code,Section XI. Our review found that Class 1, 2, and 3 safety related pumps were included in the IST program and, except for those pumps identified below for which specific relief from testing has been requested, the pump tests and frequency of testing comply with the code. Each Consumers Power Company request for relief from testing pumps, the code requirement for testing, the basis for requesting relief, and the EG&G evaluation of that request is
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summarized below and grouped according the the system in which the pumps reside:
A.
Fire and Post Incident Cooling System (M-123) 1.
Diesel and Electric Fire Pumps a.
Relief Request The licensee has requested specific relief from the Section XI requirement to measure pump parameters monthly and proposed to measure these parameters during cold shutdowns and refueling outages.
4 2
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Code Requirement An inservice test shall be conducted on all safety related pumps, nominally once each month during normal plant operation.
Each inservice test shall include the measurement, observation, and recording of all quantities in Table IWP-3100-1, except bearing temperature, which shall be measured during at least one inservice test each year.
Licensee's Basis for Requesting Relief The electric and diesel fire pumps cannot be tested during normal power operations. The valve lineup required to effectively test these pumps diverts ECCS flow that is required to mitigate the consequences of an accident by keeping the core covered.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for the electric and diesel fire pumps from the testing requirements of Section XI. The licensee has demonstrated that diverting ECCS flow required for accident mitigation is impractical for testing purposes.
tle conclude that ECCS flow is essential and must be available for safe plant operation, accident
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mitigation, and safe plant shutdown.
All pump parameters will be measured during cold shutdowns and refueling outages.
3
- b..
Relief Request The licensee has requested specific relief from the Section XI requirement to measure bearing temperature yearly for the diesel and electric fire pumps.-
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Code Requirement An inservice test shall be conducted on all safety related pumps, nominally once each month during normal plant operation.
Each inservice test shall include the measurement, observation, and recording of all quantities in Table IWP-3100-1, except bearing temperature, which shall be measured during at least one inservice test each year.
Licensee's Basis for Requesting Relief The electric and diesel fire pumps have water lubricated bearings on long shafts making them inaccessible for bearing temperature measurement.
Also, bearing temperature will vary with the water temperature being pumped and a useful reference value cannot be established.
Evaluation We agree with the licensee's basis nd therefore feel that relief should be granted for the electric and diesel fire pumps from the Section XI requirement to measure bearing temperature yearly. The licensee has demonstrated that due to the bearing inaccessibility and the variable l
r 4
temperature of cooling water pumped, a reference temperature for use in analyzing pump degradation cannot be established. We conclude that measuring bearing temperature under these conditions would not provide any meaningful data for the detection of changes in pump mechanical characteristics, and analyzing degradation.
2.
Core Spray Pumps e
a.
Relief Request The licensee has requested specific relief from the Section XI requirement to measure pump parameters monthly and proposed to measure these parameters during refueling outages.
Code Requirement An inservice test shall be conducted on all safety related pumps, nominally once each month during normal plant operation.
Each inservice test shall include the measurement, observation, and i
recording of all quantities in Table IWP-3100-1, except bearing temperature, which shall be measured during at least one inservice test each
, year.
J Licensee's Basis for Requesting Relief These pumps are part of the Emergency Core Cooling System. Testing during power operations would require a valve lineup which would preclude their performing their required function after a loss of 5
e
a coolant accident (LOCA).
In the event of a LOCA, areas which must be entered to change this valve lineup would be untenable.
In addition, testing during power operation would require personal entry into the very high radiation area directly beneath the reactor vessel.
During cold shutdown, the overall time required to perform testing is about 8 houfs.
The additional radiation exposure received for each test would be about 100 mR.
(Assumes the reactor in cold shutdown and 1/2 hour of occupancy in a 200 mR/hr radiation area under the reactor vessel).
This could possibly mean about 1200 mR additional exposure if the reactor was in cold shutdown every month of the year, due to other problems.
Evaluation We agree with the licnesee's basis-for not testing the core spray pumps 2A and 2B during power operation and therefore feel relief should be granted from the testing requirements of Section XI.
The licensee has demonstrated that the valve lineup required for effective pump testing isolates the core spray recirculation system and makes it unavailable to mitigate the consequences of an accident.
Changing the pump test valve lineup requires entry into the containment which would prevent changing to a correct safety system valve lineup following an accident.
However, we do not agree with the licensee's basis for not testing core spray pumps l
2A and 2B during cold shutdowns.
We conclude that all required pump parameters should be measured l
during cold shutdowns and refueling outages.
l 6
b.
Relief Request The licensee has requested specific relief from
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the Section XI requirement to measure bearing temperature yearly for the core spray pumps.
Code Requirement An inservice test shall be conducted on all safety related pumps, nominally once each month during normal plant operation.
Each inservice test shall include the measurement, observation, and recording of all quantities in Table IWP-3100-1, except bearing temperature, which shall be measured during at least one inservice test each year.
i Licensee's Basis for Requesting Relief i
The core spray pumps have water lubricated bearings on long shafts making them inaccessible for bearing temperature measurement. Also, bearing temperature will vary with the water temperature being pumped and a useful reference value cannot be established.
Evaluation We agree with the licensee's basis and therefore feel that relief should be granted for these pumps from the Section XI requirement to measure bearing temperature yearly. The licensee has demonstrated that due to the bearing inaccessibility and the variable temperature of cooling water pumped, a reference temperature for use in analyzing pump degradation cannot be established.
We conclude 7
that measuring bearing temperature under these conditions would not provide any meaningful data for the detection of changes in pump mechanical characteristics, and analyzing degradation.
III. Valve Testing Program The IST program submitted by Consumers Power Company was examined to verify that Class 1, 2, and 3 safety related valves were included in the program and that those valves are sub.jected to the periodic tests required by the ASME Code,Section XI, and the NRC positions and guidelines.
Our review found that Class 1, 2, and 3 safety related valves were included in the IST program and, except for those valves identified below for which specific relief from testing has been recuested, the valve tests and frequency of testing comply with the code requirements and the NRC positions and guidelines listed in General Section A.
- Also, included in the General Section A is the NRC position and valve
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listings for the leak testing of valves that perform a pressure isolation function and a procedure for the licensee's use to incorporate these valves into the IST program. Each Consumers Power Company request for relief from testing valves, the code requirement for testing, Consumers Power Company basis for requesting relief, and the EG&G evaluation of that request is summarized (B through H) below and grouped according to each specific system.
A.
General 1
Leak Testing of Valves which Perform Pressare Isolation Function I
l There are several safety systems connected to the reactor coolant pressure boundary that have design l
8 i
pressures that are below the reactor coolant system operating pressure.
There are redundant isolation valves forming the interface between these high and low pressure systems to prevent the low pressure systems from being subjected to a pressure which exceeds their design limits.
In this role the valves are performing a pressure isolation function.
It is the NRC's view that the redundant isolation provided by these valves regarding their pressure isolation function is important. The staff considers it necessary to provide assurance that the condition of each of these valves is adequate to maintain this redundant isolation and system integrity.
For this reason we believe that some method, such as leak testing, should be used to assure the condition of each valve is satisfactory to maintain this pressure isolation function.
In the event that leak testing is selected as the appropriat' procedure for achieving this objective, we believe that the fellowing valves should be categorized as A or AC and leak tasted in accordance with IWV-3420 of Section XI of the applicable edition of the ASME Code. These valves are:
M0-7056, M0-7057, M0-7058, and M0-7059 shutdown cooling system isolations Any two valves from the following sets of three valves to ensure two valve redundancy:
L M0-7071, M0-7070 core spray and redundant core spray isolation valves and VPI-303 core spray primary check j
valve.
9
t M0-7051, M0-7061 core spray and redundant core spray i
. isolation valves and VPI-304 core spray primary check L
valve.
t The NRC has discussed this matter and identified the valves listed above to the licensee.
The licensee has agreed to consider leak testing each of these valves in accordance with IWV-3420 of the applicable edition of the ASME Code and to categorize these valves with the appropriate designation.
If the licensee determines that leak testing is not necessary because there are i
other methods that the licensee has and will use to determine each valve's condition, the licensee shall provide to the NRC for evaluation on a valve-by-valve j
basis the details of the method used that clearly demonstrates the condition of each valve.
2.
ASME Code Section XI Requirements
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Subsection IWV-3410(a) of the Section XI Code (which
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discusses full stroke and partial stroke) requires the Code Category A and B valves be exercised once every 3 months, with the exceptions as defined in i
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IWV-3410(b-1),(e),and(f).
IWV-3520(a) requires that i
Code Category C valves be exercised once every 3 months, with the exceptions as defined in IWV-3520(b).
IWV-3700 requires no regular testing for Code Category E valves. Operational checks, with appropriate record entries, shall record the position of these valves I
before operations are performed and after operations are completed and shall verify that each valve is t
locked, or sealed.
The limiting value of full stroke
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time for'each power operated valve shall be identified by the owner and tested in accordance with IWV-3410(c).
In the above exceptions, the code permits the valves.to be tested at cold shutdown where:
1 10 o
a.
It is not practical to exercise the valves to the position required to fulfill their function or to the partial position during power operation.
b.
It is not practical to observe the operation of the valves (with fail-safe actuators) upon loss of actuator power.
The staff stated its position to the licensee that check valves whose safety function is to open are expected to be full-stroked.
If only limited operation is possible (and it has been demonstrated by the licensee and agreed to by the staff), the check valve shall be partial stroked. Since disk position is not always observable, the NRC staff stated that verification of the plant's safety analysis design flow rate through the check valve would be an adequate demonstration of the full-stroke requirement. Any flow rate less than design will be considered part-stroke exercising unless it can be shown that the check valve's disk position at the lower flow rate would be equivalent to or greater than the design flow rate through the valve.
The licensee agreed to conduct his flow tests to satisfy the above position.
The licensee has stated that none of the Category A or B power operated valves, can be part-stroked because of the design logic of the operating circuits.
These circuits are such that when an open or close signal is received the valve must complete a full stroke before the relay is released to allow the valve to stroke in the other direction. We find that the above relief request from part-stroking is warranted and should be granted because the required function of the valves involves only full open or full closed positions.
11
3.
Cold Shutdown Testing a.
Inservice valve testing at cold shutdown is defined as:
Valve testing should commence not later than 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after shutdown and continue until complete or plant is ready to return to power.
Completion of all valve testing is not a prerequisite to return to power. Any testing not completed at one cold shutdown should be performed during the subsequent cold l
shutdowns to meet the code required testing frequency.
We find the licensee's proposed cold shutdown condition testing acceptable.
I i
b.
The Code states that, in the case of cold shutdowns, valve testing need not be performed more often than i
once every 3 months for Category A and B valves and once every 9 months for Category C valves.
It is the our position that the code is inconsistent and that Category C valves should be tested on the'same schedule as Category A and B valves.
The licensee has agreed to modify any procedures as necessary on cold shutdown, to read, "In the case of frequent cold shutdowns, valve testing need not be performed more often than once every three (3) months for Category A, B, and C valves."
4.
Changes to the Technical Specifications In a November 1976 letter to the Consumers Power Company the staff provided an attachment entitled "NRC Staff Guidelines for Excluding Exercising (Cycling)
Tests of Certain Valves During Plant Operation." The attachment stated that when one train of a redundant system such as in the Emergency Core Cooling System (ECCS) is inoperable, nonredundant valves in the remaining train should not-be cycled since their failure would cause a loss of total system function.
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For example, during power 09eration in some plants, there are. stated minimum requirements for systems which make up the ECCS which allow certain limiting conditicns for operation to exist at any one time and if the system is not restored to meet the requirements within the time period specified in a plant's Technical Specifications, the reactor is required to be put in some other mode.
Furthermore, prior to initiating repairs, all valves and interlocks in the system that provide a duplicate function are required to be tested to demonstrate operability imediately and periodically thereafter during power operation.
For such plants this situation would be contrary to the NRC guideline as stated in the document mentioned above.
5.
Safety Related Valves This review was limited to those Class 1, 2 and 3 valves of Section XI of the ASME Code that are safety related.
Safety related valves are defined as those that are needed to mitigate the consequences of an accident and/or shutdown the reactor and to maintain the reactor in a shutdown condition.
It should be noted that the licensee may have included nonsafety related valves in their Inservice Test Program as a decision on the licensee's part to expand the scope of their Inservice Test Program.
6.
For those valves that are impractical to test quarterly, the licensee has proposed to test them at cold shutdowns or refueling outages.
In staff discussions with the licensee on (5-16-79 and 5-17-79) the licensee has agreed to change this position to test at cold shutdowns and refueling. The licensee has also l
13 i
agreed to change their definition "C/R" to cold shutdown and refueling instead of the proposed cold shutdown or refuleing.
Valve testing exceptions to the above stated position are specifically addressed in this SER.
B.
Steam and Condensate System (M-106) 1.
Category A/C Valves a.
Relief Request The licensee has requested specific relief for VRD-310, CRD pump outside containment suction check, and the CRD pump suction poppet check valves from the exercising requirements of Section XI and proposed to verify these valves open during power operation and verify these valves shut during refuleling outages.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basis for Requesting Relief 1
These check valves can be verified open during power operation by observing normal CRD pump operation. The safety function of these valves is to shut following a reactor trip. A leak rate test is required to verify valve closure.
This leak rate test will be accomplished during
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refueling outages.
14
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category A/C valves VRD-310 and the CRD pump suction poppet check valves from the exercising requirements of Section XI. The licensee has demonstrated that valve closure, full stroke exercising, can only be verified during a leak rate test because these valves are rot equipped with local or remote position indicators.
Leak rate testing is beyond the scope of cold shutdown testing but will be performed during refueling outages. We conclude that the proposed alternate testing frequency is the most practical method to ensure proper valve operability.
C.
Reactor Cleanup, Shutdown and Poison System (M-107) 1.
Category A Valves b.
Relief Request The licensee has requested specific relief from l
exercising valves CV-4091, CV-4092, CV-4093, 1
cleanup demineralizer resin sluice isolations, and CV-4027 and CV-4117, reactor and fuel pit drain 1
isolations in accordance with the requirements of Section XI.
I Code Requirement Refer to valve testing paragraph A.2.
i 15 l
Licensee's Basis for Requesting Relief These are passive valves not required to change position to perform their intended safety function.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category A valves CV-4091, CV-4092, CV-4093, CV-4027 and CV-4117 from the requirements of Section XI.
These valves are in their safety related position and are not required to open or close to mitigate the consequences of an accident or safely shutdown the plant. Therefore, the operability of these valves is inconsequential with regard to the safety function which they perform.
We conclude 3
that the quarterly stroke and stroke time measurements are meaningless for passive valves.
D.
Nuclear Steam Supply System (M-121) 1.
Category A Valves b.
Relief Request l
The licensee has requested specific relief from exercising valve M0-7065, main steam line drain isolation, in accordance with the requirements of Section XI.
^
Code Requirement Refer to valve testing paragraph A.2.
16
Licensee's Basis for Requesting Relief This normally shut, electrically disabled, containment isolation valve is a passive valve in the position required to perform its safety function.
Evaluation We agree with licensee's basis, and therefore feel relief should be granted for Category A valve M0-7065 from the requirements of Section XI. This valve is in its safety related posit, ion and is not required to open or close to mitigate the consequences of an accident or safely shutdown the plant. Therefore, the operability of this valve
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is inconsequential with regard to the safety function which it performs. We conclude that the quarterly stroke and stroke time measurements are meaningless for passive valves.
2.
Category A/C Valves a.
Relief Request L
The licensee has requested specific relief from exercising valves VFW-304, feedwater check, and VFW-9, feedwater stop check in accordance with the requirements of Section XI and proposed to verify valve opening quarterly and verify closure during the leak rate test at refueling outages.
Code Requirement Refer to valve testing paragraph A.2.
17
Licensee's Basis for Requesting Relief The check valve has no operator. The stop check valve cannot be closed against the pressure present in this line through which all feedwater to the reactor flows.
Each reactor shutdown for refueling, a local leak rate test using air is performed on these valves.
The added benefit resulting from the hand operation of the feedwater stop check valve, VFW-9, each reactor shutdown, would be minimal. All that would be proven is that the check valve disc can be forced down upon its seat (it can't be hand operated after an accident). This does not in any way prove the proper operation of the check valve.
In addition, an operator will spend about one-half hour in a high radiation area (approximately 350 mR/hr). A quarterly valve testing would result in about 700 mR/yr additional exposure. This additional personnel exposure is not offset by the incremental benefit resulting from the exercising of the feedwater check valve.
Evaluation We agree with the licensee's basis for not exercising these valves during power operation and therefore feel that relief should be granted for Category A/C valves VFW-304 and VFW-9 from the exercising requirements of Section XI.
The licensee has demonstrated that exercising these valves during power operation would result in excessive feed rate transients and possible 18
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reactor trips. VFW-304 is not equipped with position indicators or manual operators.
Therefore, valve closure can only be verified during a leak rate test at refueling outages.
VFW-9 is not equipped with position indicators but is equiped with a manual operator which can be used to move the valve disc shut which is its safety related position. Valve closure can only be verified during a leak rate test during refueling outages. The leak rate tests are beyond the scope of cold shutdown testing. We conclude that VFW-9 should be manually exercised shut during cold shutdowns and the both VFW-9 and VFW-304 should be verified shut during the refueling outage leak tests.
3.
Category C Valves a.
Relief Request The licensee has requested specific relief from exercising valves VP-301, liquid poison supply to recirculating pump suction, and VP-302, liquid poison supply to Rx vessel, in accordance with the requirements of Section XI and proposed to full stroke exercise these valves during refueling outages.
Code Requirement l
Refer to valve testing paragraph A2.
l l
19
Licensee's Basis for Requestina Relief I
i These check valves have no operators and exercising by initiating flow in the system would-
,f require introducing liquid poison into the_
reactor. These valves will be full stroke
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i exercised by manual operation after disassembly.
t
- t Evaluation
[
We agree with the licensee's basis, and therefore i
feel relief should be granted for Category C l
valves VP-301 and VP-302 from the exercising i
requirements of Section XI. The licensee has
[
demonstrated that injecting liquid poison into the s
reactor plant during power operation would cause severe power transients and could result in a reactor trip. During cold shutdown injecting l,
liquid poison would delay reactor start up while l
the poison was filtered out of the reactor system. We conclude that the proposed alternate test of disassembly and manual operation during
.f j-refueling outages to full stroke exercise these valves is the most practical method available to 4
j ensure operability.
I 1
i E.
Fire and Post Incident Cooling System (M-123)
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l i
l 1.
Category-B Valves i
1.
i a.
Relief Request i,
The licensee has requested specific relief from exercising valves M0-7064 and'M0-7068, enclosure spray isolations, in accordance with the i
20 L
t
requirements of Section XI and proposed to full stroke exercise these valves during refueling outages.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basis for Requesting Relief These valves cannot be exercised during power operation without spraying water on energized electrical equipment inside the containment.
These valves cannot be exercised during cold shutdowns because the fire system header must be taken out of service and drained to allow exercising of the valves.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category B valves M0-7064 and M0-7068 from the exercising requirements of Section XI. The licensee has demonstrated that exercising these valves during power operation would result in damage to equipment located inside the containment. Also, that exercising these valves during cold shutdown would require taking the fire system out of service. We conclude that exercising these valves more often than refueling outages only increases the possibility that the fire system would be unavailable to mitigate the consequences of an accident.
I I
21 l
2.
Category C Valves a.
Relief Request The licensee has requested specific relief from exercising valves VPI-303 and VPI-304, CS primary checks, in accordance with the requirements of Section XI and proposed to disassemble, inspect, and verify free disc movement during refueling outages.
Code Requirement Refer to valve testing paragraph A2.
Licensee's Basis for Requesting Relief The CS primary check valves have no operators.
The valves cannot be opened against operating reactor pressure by initiating flow through these lines, because core spray system pressure is much less than operating reactor pressure.
During shutdown, the initiation of flow through these lines would introduce nonreactor grade water into the core.
The only means to insure proper valve operation is to disassemble and inspect the valve during each reactor shutdown for refueling.
There exists no method to insure disc movement torque requirements are met.
The valve will be inspected and verified that the disc is free to move.
D J
22
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category C valves VPI-303 and VPI-304 from the exercising requirements of Section XI. The licensee has demonstrated that core spray pressure cannot overcome operating reactor system pressure which prevents valve operation.
In addition, flow exercising these valves during cold shutdown requires injecting non-RCS grade water into the reactor coolant system resulting in severe chemical and cleanup problems which would delay plant startups. We conclude that since these valves are not equipped with external operators or position indicators, that the most practical method to ensure proper valve operability is the I
disassembly, inspection, and manual verification of free disc movement during refueling outages.
b.
Relief Request The licensee has requested specific relief from exercising valves VPI-300, VPI-306, and VPI-307, core spray checks, from the exercising requirements of Section XI and proposed to full stroke exercise these valves during refueling outages.
Code Requirement Refer to valve testing paragraph A2.
23
Licensee's Basis for Requesting Relief These valves are part of the Emergency Core Cooling System. Testing during power operations would require a valve line-up which would preclude
~
their performing their required function after a loss of coolant accident (LOCA).
In the event of a LOCA, areas which must be entered to change this valve lineup would be untenable.
In addition, testing during power operation would require personnel entry into the very high radiation area directly beneath the reactor vessel.
~
During cold shutdown, the overall time required to perform testing is about 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The additional radiation exposure received for each test would be about 100 mR.
(Assumes the reactor in cold shutdown and 1/2 hour of occupancy in a 200 mR/hr radiation area under the reactor vessel). This could possibly mean about 1200 mR additional P
exposure if the reactor was in cold shutdown every month of the year, due to other problems.
Evaluation We agree with the licensee's basis for not testing the core spray checks, VPI-300, VPI-306 and VPI-307 during power operation and therefore feel relief should be granted from the testing requirements of Section XI.
The licensee has demonstrated that the valve lineup required for effective pump testing and full stroke exercising isolates the core spray recirculation system and l
makes it unavailable to mitigate the consequences of an accident. Changing the full stroke testing valve lineup requires entry into the containment 24 a
i which would prevent changing to a correct safety f
system valve lineup following an accident.
However, we do not agree with the licensee's basis for not testing valves VPI-300, VPI-306, VPR-307 during cold shutdowns. We conclude that full l
stroke exercising should be accomplished during I
cold shutdowns and refueling outages.
l F.
Reactor Depressurization System (M-A203) 1.
Category A Valves a.
Relief Request i
The licensee has requested specific relief from full stroke exercising valves SV-4984, SV-4985, SV-4986, and SV-4987, depressurizations for RDS, in accordance with the requirements of Section XI and proposed to partial stroke exercise these valves during cold shutdowns and refueling outages.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basic for Requesting Relief These valves cannot be full stroke exercised unless continuous primary system pressure is applied, releasing a large volume of primary steam into the containment and exposing personnel and equipment to adverse conditions. During testing, pressure in the spool piece between the isolation valve and the depressurization valve is relieved i
25
before the depressurization valve reaches the fully stroked position.
Thus, only partial stroking of the valve is possible during testing and no valve stroke timing can be performed.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category A valves SV-4984, SV-4985, SV-4986, and SV-4987 from the exercising requirements of Section XI.
The licensee has demonstrated that full or partial stroke exercising the valves during power operation would cause large-uncontrolled pressure transients that could cause a reactor trip.
The licensee has also demonstrated that full stroke exercising these valves during cold shutdown would result in an excessive amount, approximately 144 lb. stm./sec. for each valve, of primary water being dumped into the containment requiring an extensive clean-up following a test.
During present testing, pressure in the spool piece between the isolation valve and the e
depressurization valve is relieved before the depressurization valve is full stroke exercised.We conclude that the licensee's proposed testing is the only practical test method with the present piping configurations.
G.
Make-up and Condensate Demineralization System (M-110)
I r
1.
Category A/C Valves i
k 26
a.
Relief Request The licensee has requested specific relief from exercising the demineralization supply check valve downstream of CV-4105 in accordance with the requirements of Section XI and proposed to exercise this valve open quarterly and to exercise this valve and verify closure during refueling outages.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basis for Requesting Relief This valve can be verified open by observing i
normal demineralized water flow during power operation. The safety function of this valve is to shut on reversal of flow. A leak rate test is required to verify valve closure.
Evaluation 1
We agree with the licensee's basis, and therefore feel relief should be granted for Category A/C demin supply check valve from the exercising requirements of Section XI. The licensee has demonstrated that the only time valve closure, full stroke exercising, can be verified for valves i
without position indicators is during a leak rate This leak rate test is beyond the scope of test.
cold shutdown testing, and will be performed during each refueling outage. We conclude that the proposed alternate testing frequency is the most practical method available to ensure proper valve operability.
27
H.
Radwaste System (M-108) 1.
Category A Valves a.
Relief Request The licensee has requested specific relief from exercising valve CV-4049, treated waste to refueling shield tank containment isolation, in accordance with the requirements of Section XI.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basis for Requesting Relief This normally shut, power operated, containment isolation valve is a passive valve in the position required to perform its safety function.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category A valve CV-4049 from the requirements of Section XI.
This valve is in its safety related position and is not required to open or close to mitigate the consequences of an accident or safely shutdown the plant. Therefore, the operability of this valve is inconsequential with regard to the safety P
function which it performs. We conclude that the 1
quarterly stroke and stroke time measurements are meaningless for passive valves.
l 28
2.
Category /,/C Valves a.
Relief Request
^
The licensee has requested specific reiief from exercising valve VRW-313, treated waste to refueling shield tank cnntainment check, in accordance with the requirements of Section-XI.
Code Requirement Refer to valve testing paragraph A.2.
Licensee's Basis for Requesting Relief This normally shut containment isolation check j
valve is in the position required to perform its safety function. A leak rate test is required to verify valve closure.
Evaluation We agree with the licensee's basis, and therefore feel relief should be granted for Category A/C valve VRW-313 from the exercising requirements of Section XI. Thisialveis.aitssafetyrelated position and is not required to open or close to mitigate the consequences of an accident or safely shutdown the plant. Therefore the operability of this valve is inconsequential with regard to the safety function which it performs. We conclude that the quarterly stroke and stroke time measurements are meaningless for passive valves.
4 i
29
IV. Attachment I A.
Appendix J Exemption Requests 1.
The NRC is presently reviewing the Big Rock Point Appendix J exemption request from leak testing the following valves in accordance with the requirements of Appendix J.
CV-4107 CV-4104 M0-7067 Turbine Stop Valve If ir, exemption is authorized, the above mentioned valves will ue exempt from the leak testing requirements of Appendix J and Section XI.
If this exemption is not authorized, plant modifications will be required to ensure Seak testing will be in accordance with the requirements of Appendix J and Section XI.
I i
e a
30
V.
Attachment II The following are Category A, B, and C valves that meet the requirements of the ASME Code Section XI and are not full stroke exercised every three months during plant operation.
These valves are specifically identified by the owner and are full stroke exercised during cold shutdowns and refueling outages.
EG&G has reviewed all valves in this attachment and agrees with the licensee that testing these valves during power operation is not possible due to the valve type and location, system design, or because this action would place the plant in an unsafe condition. We feel these valves should not be exercised during power operation.
These valves are listed below and grouped according to the system in which they are located.
A.
Reactor Cleanup, Shutdown, and Poison Systems (M-107) 1.
Category B valves MO-7053 and M0-7063, emergency condenser discharge isolations, cannot be exercised during power operation.
Opening these normally shut valves would admit operating temperature steam to the emergency condenser causing unnecessary thermal stresses and eventual damage to the tube bundles.
These valves are full stroke exercised during cold shutdowns and refueling outages.
2.
Category C check valve VP-300, liquid poison system supply check, cannot be exercised during power operation. This valve has no operator and a test pressure cannot be applied to verify valve closure without breaching the primary pressure boundary and releasing primary steam. The checking capability (safety position) test will be performed during each cold shutdown and refueling outage when a test pressure can be applied upstream of valve VP-300.
3.
I
3.
Category B valves M0-7056, M0-7057, M0-7058, and M0-7059, shutdown cooling system isolations, cannot be exercised during power operation. The shutdown cooling system has a design pressure of 300 psig. Opening these normally shut valves during power operation would overpressurize and damage the shutdown cooling system.
These valves are. full stroke exercised during cold shutdowns and refueling outages.
4.
Category B valves M0-7052 and M0-7062, emergency condenser inlet isolations, cannot be exenised during power operation. Shutting these valves during power operation would isolate flow to the emergency condenser and prevent safety system operation if the valves were to fail in the non-conservative position.
These valves will be full stroke exercised during cold shutdowns and refueling outages.
t 5.
Category B valve CV-4020, liquid poison discharge isolation, cannot be exercised during power operation.
Shutting this valve and failure of this valve to open would render the liquid poison system inoperable.
This valve will be full stroke exercised during cold shutdowns and refueling outages.
B.
Control Rod Drive System (M-122) 1.
Category B valves CVNC-09 and CVNC-10, scram inlet and outlet valves, cannot be exercised during power operation. Ooening these normally closed valves would cause the associated control rod to scram.
These valves will be full stroke exercised following each cold shutdown and refueling outage within 7 days prior to reactor critical approach.
l 32
2.
Category C valves VFP-304 and VFP-309, fire pump discharge checks, cannot be exercised during power operation.
Exercising these normally shut valves requires fire pump operation. The fire pumps cannot be tested during power operation because the full flow lineup limits the amount of ECCS flow to the core that is required for accident mitigation.
These valves are full stroke exercised during cold shutdowns and refueling outages.
B.
Nuclear Steam Supply System (M-121) 1.
Category A valve M0-7050, main steam isolation, cannot be exercised during power operation.
Shutting this valve would result in the interruption of all main steam flow causing a turbine trip followed by a reactor trip.
This valve will be full stroke exercised during cold shutdowns cod refueling outages.
2.
Category B valve CV-4050, liquid poison supply to recirculation line, cannot be exercised during power operation. This valve is interlocked to automatically open when either recirculating pump is operating.
Securing the recirculating pumps during power operation would place the plant in an unsafe condition and result in a reactor trip.
This valve will be full stroke exercised during cold shutdowns and refueling outages when the recirculating pumps are secured.
e 33
D.
Fire and Post Incident Cooling System (M-123) 1.
Category C valves VPI-301 and VPI-302, CS primary and back-up check valves, cannot be exercised during power operation. These secondary check valves have no operators for manual operation. Testing these valves requires that the core spray system be taken out of service thus making the system unavailable to perform its safety function. These valves will be full stroke r
exercised during cold shutdowns and refueling outages using fire water system flow.
l e
6 I
l l
9 34
VI. Attachment III The P& ids listed below were used during the course of this review.
System P&ID Rev.
i Steam and Condensate M-106 S
Reactor Cleanup - Shutdown - Poison M-107 M
Radwaste M-108 Q
Make-up and Condensate Demin.
M-110 K
Circulating, Cooling, and Service Water M-111 S
Nuclear Steam Supply M-121 L
Control Rod Drive M-122 M
Fire and Post Incident Cooling M-123 AB Turbine Bldg. and Service Bldg. Ventilation M-124 G
Reactor Bldg. Vent, Heat and Cooling M-125 P
i Service and Instrument Air M-133 F
Reactor Depressurization i
A-203 C
4 t
I F
p l
l 4
t b
e t
i I
l
\\
i i
35
VII. Attachment IV i
A.
Valves that are never full stroke exercised or that have a testing frequency greater than each refueling outage:
i 1.
SV-4984 through SV-4987 depressurization for RDS B.
Relief requests with insufficient technical basis where relief was not recommended:
I 1.
Pump Testing Program i
l j
a.
Core Spray 2.a i
2.
Valve Testing Program
'r a.
Nuclear Steam Supply 2.a
~
b.
Fire and Post Incident Cooling 2.b i
a e
f I
r i
i t
36 i
_ - _.