ML20244B950
| ML20244B950 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 06/02/1989 |
| From: | Stewart W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 89-298, NUDOCS 8906140063 | |
| Download: ML20244B950 (17) | |
Text
\\
i.
VIRGINIA ELECTRIC AND POWER COMPANY RICIIMOND, VIRGINIA 23261 June 2,1989 W. L. STEW A RT SENick Vice PRESIDENT POWER U. S. Nuclear Regulatory Commission SerialNo 89-298 Attn: Document Control Desk NT/TMW:cmh Washington, D. C. 20555 Docket No.
50-338 50-339 License No.
NPF-4 NPF-7 Gentlemen:
VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION UNITS 1 AND 2 SIMULATOR CERTIFICATION in Response to your letter of April 13, 1989, requesting additional information in support of the certification of the North Anna Control Room simulator, we are forwarding the requested information as an attachment to this letter.
If you have further questions, please contact us.
Very truly yours, 1A
[
W. L. STEWART 1
Attachment cc:
U. S. Nuclear Regulatory Commission 101 Marietta Street, N.W.
Suite 2900 Atlanta, GA 30323 Mr. J. L. Caldwell NRC Senior Resident inspector North Anna Power Station b
I 1
8906140063 890602 ADOCK0500g]8
{
PDR P
h VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA UNITS 1 AND 2 SIMULATOR CERTIFICATION RESPONSES TO QUESTIONS IN NRC LETTER OF APRIL 11, 1989 i
The following responses are provided to your request for further clarification of data provided in the North Anna Simulator Certification Document.
Question 1 Throughout Attachment 3, " Simulator Test Results," very few discrepancies were noted and in the " Transient Test Results" and " Malfunction fest Results" l
sections of this attachment, no discrepancies were noted.
However, in
., " Discrepancy Backlog /and Resolution Schedule," 167 discrepancies I
were documented as open items at the time of certification.
These included such seemingly important deficiencies as:
SMR. NUMBER SYS DESCRIPTION l
8803311115 CN (partial) " Condenser vacuum doesn't change when steam to air ejectors is stopped."
8602141602 EL (partial) " Currently all recorders continue to operate during loss of power simulation."
8703041700 FW "The energy balance of the FW heaters is not correct. After turbine trips heaters are not able to generate any heat transfer causing the feedwater temp to drop from approx 450 F to approx 75 F in a few seconds."
8710221300 IA "From ICI with IA containment TU's shut & no 1A compressors running in the containment, air pressure does not decrease.
1 understand the system in the simulator does not have leakage.
Air leakage is normal in all air sys & must be simulated with some small amount!"
8703191050 HC "ECA0.0 requires operators to vent off H2 in main generator.
Unable to do.
Modify with a vent valve to depressurize (several other procedures also have you perform this evolution!)."
8509121534 PC
" Anytime core is aged to EOL conditions the AFD alarm comes in & creates unnecessary problems.
It appears when you age the core 1
(
Y L
.it still.looks at the BOL target & thus creates this problem.
- This situation needs to be corrected prior to NRC exams."
8806060840 MS
" Simulation shows an excessive' load decrease when main steam intercept & reheat stop valves are closed.
The simulation' shows 130MW decrease.
It should be around a 40 MW
,~
decrease."
8405160850 RD "During recovery of rod, in bank select C, drove rod bank in- (with malf active) reactor tripped on high power - (spike).
This action results in no actual rod motion &
l therefore no reactivity change.
I.E.
power spike & should not have."
8704131235 TU (partial) " Malfunction causes trip, cycles turbine valves and wild plant response.
Should only cause low pressure alarm and start the stby. pump."
Please explain why the documented results of your performance testing appear-
- to conflict with. the ' documented discrepancies.
Also, please provide a description of the' baseline data used to determine fidelity.to the reference plant.. If the baseline data used was the judgement of a panel of experts, then documentation'of their review, sufficient;for a third party to evaluate
' the adequacy of the tests and results,. should be included. This documentation may include such items as the makeup and qualification of the panel and any differing professional opinions as to the outcome of the tests.
Answer 1 Virginia Power has been engaged in a comprehensive review and upgrade of
- the North Anna simulator hardware and software.
In addition to the review, a stated goal of the upgrade was to systematically recolve the large number of discrepancies which had been identified.
The upgrade is now in the last year of the project.
Our tests for malfunctions are intended to ensure all automatic actions occur including the immediate operator actions taken ' until the plant is stabilized following the event.
Transient testing is conducted under conditions similar to that described for u.alfunction testing, except no malfunction or upset events are introduced during the test.
Malfunction
- testing was performed under single malfunction active, steady state plant
- conditions, with all systems and controls in normal configurations.
In some cases, the test date of a malfunction can precede the date. a discrepancy was identified.
Experience has indicated that discrepancies are usually identified during the implementation of scenarios involving multiple events and long term (8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />) simulator operations in a single set of initial conditions.
In such cases, the individual malfunction test results can be satisfactory, but when the design envelope of the model(s) is exceeded, new
3 multiple event scenarios 'are developed, or the simulator is operated under conditions other than usual and customary, additional discrepancies are identified.. All discrepancies are evaluated for impact, and in consultation with the North Anna Lead Simulator Instructor, prioritized and scheduled for resolution. Attachment 9 of the certification submittal provides information regarding discrepancy. evaluation and resolution methodology used by. Virginia Power.
As of '05/12/89, 61 of the original (167) open discrepancies.. (Simulator Modification Report - SMR) listed in the submittal remain to be resolved. The status of the discrepancies specifically identified, is as follows:
SMR Number SYS Status 8803311115 CN This discrepancy has been closed.
The event
-identified occurred when steps were performed in an abnormal sequence of operations.
8602141602 EL The original scope of simulation did not include deenergizing. recorders.
During the system scope review, this was identified as a problem.
Implementation of this feature is a labor intensive project which is currently in progress and is scheduled for completion by 06/30/89.
8703041700 FW Energy balance for at power operations are satisfactory.
Energy balances with the unit off line have little impact unless prolonged steady state operations occur in this situation, which is not the norm.
Usually the plant is immediately restarted or a cooldown is implemented. This discrepancy is scheduled for completion by 09/30/89.
8710221300 1A The original system scope of simulation did not provide for system leakage.
Impact on training was negligible.
This discrepancy has been addressed with completion of the Compressed Air System upgrade.
8703191050 HC This event can be performed through various override capabilities and role playing by the instructor.
This function is performed infrequently. This discrepancy is scheduled for completion by 07/31/89.
8509121534 PC The resolution of this problem has required significant resources be expended and is still in progress.
The solution will directly affect the plant computer and reactor core models, both of which are currently in development and scheduled for testing and implementation by 06/30/89.
- s 4
8806060840 MS This discrepancy was identified via performance of the Periodic Test for Turbine Valve Freedom.
While the magnitude of the decrease was excessive, the direction or rate did not provide negative training.
This discrepancy is scheduled for resolution by 07/15/89.
8405160850 RD This discrepancy occurred during a multiple event scenario, unlike that under which the malfunction test was conducted.
The discrepancy has been resolved.
8704131235 TU This discrepancy ' involved a non-certified malfunction which is infrequently used.
The discrepancy has been resolved.
The baseline data 'used to determine fidelity with the reference plant included a control board item by item comparison in conjunction with a system piping and instrumentation review to ensure all components visible or controllable from the control room were included in the simulator. A review of unit operating procedures is performed to ensure appropriate local components operable by an outside operator are available to enhance the
. instructor's capability' to provide high quality simulator training to all students.
Other documents reviewed include electrical wiring diagrams, logic diagrams, various vendor documents, the updated Final Safety Analysis Report and station operator logs and test results where available.
Early in the upgrade proj ect it was identified that data volds would occur.
An appropriate solution to resolve data voids was the use of an identified team of specialists.
The team of specialists includes the Lead Simulator instructor (SRO licensed), the Simulator Support Coordinator (R0 licensed), Simulator Support Group Software Engineers (Mechanical Engineer, Chemical Engineer, Engineering Science. Physics).
Other station / corporate personnel, as appropriate, are utilized to ensure the simulator response is satisfactory.
The feedback of the instructor staff and qualified trainees, such ae LORP students, is solicited to ensure simulator response accurately matches the station. Upon completion of a modification, the lead simulator instructor is formally required to review the change to ensure the simulator response is appropriate.
When the lead. instructor agrees, it is documented via the discrepancy report which tracks the history of a discrepancy through implementation and documentation.
Additionally, a commitment has been made to ensure that appropriate i features of the 1NPO Good Practice document TQ504, Simulator Configuration l
Management
- System, are incorporated into the Simulator Support Group I'
methodology.
The commitment, CTS 870007-001, is scheduled for implementation by 01/31/90.
3 l
5 Question 2
'The " Steady State Stability" test at 100 percent power described on page 18'of appears to be the only test performed for steady state operation.
ANSI /ANS-3.5-1985, Section 4.1, specifies the performance criteria for steady state' operation and requires that "During testing, the accuracy of computed values shall be determined for a minimum of three poincs over the power range."
Please provide performance test abstracts for the tests required by ANSI /ANS-3.5-1985, Section 4.1 or provide justification for exception to these requirements.
Answer 2 The 100: percent power test described on page 18 of Attachment 3 is correct. -However, our interpretation of this requirement is specifically related to the performance of calorimetric during load increases via normal station operating: procedures.
The North Anna station operating procedures require several hold points to verify nuclear power. distribution and stability.- A calorimetric is only performed at 98% reactor power.
Since our-tests are based on accepted station procedures, it was determined unnecessary to specifically state this as an exception.
Because' of the various hold
. points to verify core stability and flux distribution, the intent of Section 4.1 has been met during Plant Startup from Hot Shutdown to Full Power which was reported on page 23 of Attachment 3.
During the performance of the latter
' test, the calorimetric was performed in accordance with and via station operating procedures.
The abstract needs the following added after the last
' statement.
"The accuracy of computed values over a minimum of three points over the power range was satisfied via the test performed on page 23 of."
l L
1
~
y --'
g I
)
r 1
Question 3 1
The " Full Power Trip end Recovery" test described on page 19 of Attachment 3 appears to be intended to fulfill the requirement' of ANSI /ANS-3.5-1985, Section 3.1.1(4),
" Reactor trip followed by recovery to rated power."
llowever, this-test only. returned the plant to hot standby conditions.
Please
- provide justification for exception to " recovery to rated power."
Answer 3 The test performed did include recovery to rated power, but the test abstract is incomplete. The abstract needs the following added after the last statement of paragraph 2, "The plant was then ramped to 100 percent power using plant procedures."
._u.-_-_-2._m_
.__m__.--..,._-_--_-_.--_..-______--__m-
L 7
Ouestion 4 The tests - described - in Attachment 3 do ' not appear to -include tests. for ANSI /ANS-3.5-1985, Section 3.1.1 " Normal Plant Evolutions " items:
"(5) Operations at hot standby";
"(7) Startup, shutdown and power operations with less than full reactor coolant flow"; and
"(9) Core performance testing such as plant heat balance, determination of
, shutdown margin, and measurement of reactivity coefficients and control rod worth using permanently installed instrumentation."
.Please provide performance test. abstracts for these tests or provide justification for exception to performance of these tests.
Answer 4(5)
Operations at hot standby were performed in accordance with normal station operating procedures, which is satisfied vi.a the tests performed on pages 19 and 22 of Attachment 3.
On page 19 the abstract indicates the plant was returned to Hot Standby conditions,. while page 22 states the startup "was secured when stable' hot standby conditions existed".
In order to clarify the scope of the test, the i
abstract on page 22 should have been entitled " Plant Startup to Hot Standby Conditions."
Answer 4(7)
Tests performed' under " Normal plant Evoluticns" were conducted as indicated in the abstracts.
Tests were performed under the same limitations the. station operates under.
Power operations with less than full reactor coolant flow is precluded by North Anna Technical Specifications, therefore this particular test was considered inappropriate.
Answer 4(9)
Core performance testing with permanently installed instrumentation is l
limited to heat balance, shutdown margin, and ECP calculations.
A deficiency I
regarding the core being out of date had been previously identified.
A f
b complete core cycle update and enhancement is currently underway with a projected completion date of 06/30/89.
When the upgrade has been completed, appropriate integrated plant operations
- tests, as well as selected malfunctions will be performed to ensure the upgrade is satisfactory and meets the requirements of training personnel. Permanently installed instrumentation L
does not support measurements of reactivity coefficients and rod worths.
1 i
l-
- 3.. -
8
'It-should. be noted the ECP and shutdown margin calculations were performed as required by station procedures during the: course of integrated operations testing.
Consequently the need.to. specifically state their performance was not considered necessary. The following statement needs to be added af ter the last statement of the abstract on page 22 of Attachment 3, "ECP calculations were~ performed in accordance with station procedures.
A l..
suberitical multiplication ratio plot was performed to. verify the ECP."
I'
' Add the following statement af ter the last statement of the abstract on page. 23 of Attachment'-3
" Heat balance was performed in. accordance.with station procedures.. Difficulties with the plant computer vere reidentified.
The plant computer model upgrade is scheduled for completion by 06/30/89."
d
g
' Question 5 Is'the " Main Turbine Trip" test described on page 26 of Attachment 3 intended to satisfy the requirement of ANSI /ANS-3.5-1985, Appendix B, item B.2.2(6),
" Main turbine trip (maximum power level which does not result in immediate reactor trip)"?
If so, please confirm that 10 percent power is the " maximum
. power level which does not result in immediate reactor trip."
If not, please provide the performance test abstract for the test meeting this requirement or provide justification for exception.
Answer 5 The " Main Turbine Trip" test on page 26 of Attachment 3 is intended to satisfy the requirement ANSI /ANS-3.5-1985, Appendix B,
item B.2.2(6).
The maximum power level which does not result in immediate reactor trip is 10%
based on permissive P-7 which requires 2 of 4 nuclear power range instruments indicate greater than or equal to 10% power before the low power, power range reactor trip is enabled or 1 of 2 first stage turbine pressure instruments-indicate greater than or equal to 10% turbine pressure.
c-10 b
k;
' Question 6 1
Upon review of the " Transient Test Results" and " Malfunction Test Results" in
- it is not cicar that the simulator includes all of the " Plant
- Malfunctions" required by ANSI /ANS-3.5-1985, Section 3.1.2, especially items:
"(6) Loss of service water or cooling to individual components";
'"(11) Loss of protective system channel"; and
"(14) Fuel cladding failure resulting in high activity in reactor coolant or i
off gas and associated high radiation alarms."
Please. confirm that the simulator includes all the malfunctions required by ANSI /ANS-3.5-1985 or provide' justification (s) for any exceptions. This may be done by providing a cross reference of the malfunction numbers to the malfunctions listed in ANSI /ANS-3.5-1985, Section 3.1.2.
~
Answer 6 All of the " Transient Test Results" and " Malfunction Test Results" in ' are intended to meet the requirements of ANSI /ANS-3.5-1985, Section 3.1.2.
Item 6 is addressed. by MSW01 malfunction abstract on page 78 of Attachment 3.
Loss of cooling to individual components is handled via instructor console features such as overrides and local component operation.
Item 11 is addressed indirectly through numerous malfunctions specifically identified with the system in which it is located.
For your convenience, the following list identifies the certified malfunctions which, in our opinion satisfy the intent of " loss of protective system channel":
MEL12 LOSS.OF SEMI-VITAL BUS MEL13 LOSS OF AC VITAL BUS INVERTER MELl7-LOSS OF PRIMARY PROCESS RACK POWER SUPPLY MFWOI STEAM GENERATOR LEVEL TRANSMITTER FAILURE (0-100%)
MFW12 MAIN FEED FLOW TRANSMITTER FAILURE MMS 01 STEAM FLOW TRANSMITTER FAILURE MMS 02 TURBINE FIRST STAGE PRESSURE TRANSMITTER FAILURE MMS 16 FAILURE OF STEAM HEADER PRESSURE CONTROL (0-100%)
MNIO9' 1 INTERMEDIATE RANGE DETECTOR FAILURE MNIl0 SOURCE RANGE CHANNEL FAILURC MNI13 POWER RANGE CHANNEL FAILURE MQS03 FAILURE OF CONTAINMENT HIGH PRESSURE TO INITIATE SPRAY MRC07 PRESSURIZER PRESSURE TRANSMITTER FAILURE MRC08 PRESSURIZER LEVEL TRANSMITTER FAILURE 7
MRCl1 REACTOR COOLANT FLOW TRANSMITTER FAILURE MRC15 CONTROL RTD FAILURE IN COLD LEG MRC17 PROTECTION RTD FAILURE IN HOT LEG
11 MRC18 PROTECTION RTD FAILURE IN COLD LEG MRC29 PRESSURIZER PRESSURE CONTROL FAILS MRC33 PT-402 WIDE RANCE PRESSURE TRANSMITTER FAILURE MRC34 PT-403 WIDE RANGE PRESSURE TRANSMITTER FAILURE MSIO7.-
. FAILURE OF ONE SAFETY INJECTION TRAIN TO ACTUATE MSIO8~
FAILURE OF ANY SAFETY INJECTION SIGNAL TO CAUSE SAFETY INJECTION MTUO2 '.:
FAILURE OF MANUAL TURBINE TRIP TO FUNCTION ON DEMAND
'MTUO3 FAILURE OF AUTO TURBINE TRIP TO FUNCTION ON DEMAND Item 14 is addressed via MRC31 (Fuel Leak) malfunction as stated.in the~
test abstract on page 64 of Attachment 3 which satisfies the intent of fuel l-cladding faib re.
1 L__ _
y, 12
.,D
'_uestion 7 Q
Are the " Periodic Tests" listed on page'85 of Attachment 3 inclusive of all
" Operator conducted surveillance testing on safety-related equipment or
. systems" as required by ANSI /ANS-3.5-1985, Section 3.1.1, item (10)? If not,
- please confirm that the simulator is capable of meeting this requirement or provide justification for exception.
-Answer 7 The " Periodic Tests" listed on page 85 of Attach.nent 3 do not include all operator conducted surveillance testing on safety-related equipment or systems.
The periodic tests listed include those tests which are most appropriate for performance on the simulator or which would provide meaningful training if conducted on the simulator.
The list of periodic tests to'be performed was developed and agreed to in a joint effort by the simulator support group staff and the North Anna' simulator / operator instructor staff which included an evaluation of the RO/SRO job task analysis.
'l
\\
i
Q, tz t
13 Question 8, the." Simulator Test Schedule," states "The Transient Performance Tests of' ANS-3.5-1985 - Appendix B section B.2.2' will be conducted annually."
ANSI /ANS-3.5-1985. Appendix B,-Section B.2.1, " Steady State Performance" tests are also required annually.. Please confirm your intent to perform steady state tests as well as transient tests or provide-justification for exception.
l' Answer 8 l
" Steady State Performance"' tests will be performed. annually.
The-
" Simulator Test Schedule" in Attachment 4 needs to have the following statement added for each year under the " Integrated Tests" heading:
" Steady State Performance test."
l l
14 Question 9 In Attachment 5, " Physical Fidelity Report," on page 5, Item 6 of the "Overall Control Room ' Items" indicates that the sound powered phone system is not I
functional and will remain as such.
Also, in Attachment 5, on page 45, items L
2 and 6 under "Shif t Supervisor Console" indicate that other communications systems do not work.
" Control Room / Simulator Panel and Environment Comparison," on pages 14 and 15, in regard to the Shift Supervisor's Console, also indicates that some communications systems are not completely functional.
ANSI /ANS-3.5-1985, Section 3.2.3,
" Control Room Environment" requires that " communication systems that a control room operator would-use to communicate with an auxiliary operator or other support
' activities shall be operational to the extent that the simulator instructor, when performing these remote activities, shall be able to communicate over the appropriate - communication system."
Please confirm that the simulator meets this requirement or provide justification for exception.
Answer 9 Attachments 5 and 6 were intended to document identified discrepancies between the station and simulator control panels / environment for resolution either immediately or after the suitable evaluations have been performed.
In some cases the discrepancy has been identified to have no action taken,
- however, the discrepancy so identified is periodically reviewed for implementation to accommodate changing training requirements,. changing NRC requirements and economic competition for valuable utility funds.
Specifically, the sound powered phone system in question is used solely by Instrument and Control personnel during instrumentation calibration.
Operations personnel rarely use the system, except during refueling, which we are not required to model per ANSI /ANS-3.5-1985 Section 3.1.1 item (1).
The radio system and the complete AT&T telephone system is not fully operabic.
The upgrade of the radio and telephone system is currently under review for upgrade.
When the review has been completed, appropriate action will be taken commensurate with the results of the review.
However, other normally available communications systems, such as the intercom system is operable. The ability to use the current general telephone system to contact the instructor's booth to simulate communications with various station personnel is available.
Offsite communications via the NRC ring down system and other offsite agencies is provided consistent with the system installed in the station.
Therefore, the simulator does meet the requirement to allow adequate communications to perform remote activities.
15 Question 10 Attachment. 6, on page 14, under " Plant Computer Station" ' states that "The reference plant computer station is fully simulated with the exceptions of some tasks tha't are beyond the scope of simulation."
ANSI /ANS-3.5-1985, Section 3.2.2,
" Controls on Panels," requires.that "... plant computer interface hardware and other components or displays that would function during normal, abnormal, and emergency evolutions shall be included in the simulator."
Please confirm that this requirement is met or provide justification for exception.
' Answer 10' The plant computer interface hardware and other components or displays that would function during normal, abnormal and emergency evolutions are
-included in the simulator.
The original scope of simulation only modeled those features the operator uses in the course of performing their assigned tasks, therefore, some engineering tasks were not included. As the simulator has been modified, additional modifications have been identified to make the plant computer more useful to the operations staff during simulator sessions.
The - plant computer model has been in sof tware development for over six months and is currently scheduled to be completed by 06/30/89.
y;
~
16 K-Question 11 For Unit 2 two NRC Forms 474 were included in your submittal.
One was.
unsigned but had the box for exceptions checked. The other was signed but did not have the box for exceptions checked.. Please confirm that, for Unit 2, the Unit I simulator meets the guidance contained in ANSI /ANS-3.5-1985, as endorsed.by.
NRC ' Regulatory Guide 1.149, without exception or provide justification for any exceptions taken..
Answer 11 The intent was to certify Unit. 2 on NRC. Form 474 with the box for exceptions checked.
The information; in Attachments 1 and 2 vere intended to prove the identified. differences were of a minor nature.
Therefore, there is no reason why the Unit I simulator cannot be used as the reference plant simulator for Unit 2.
-- -