ML20238D735
| ML20238D735 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 06/22/1987 |
| From: | Larson C NORTHERN STATES POWER CO. |
| To: | Dudley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20238D709 | List: |
| References | |
| NUDOCS 8709110363 | |
| Download: ML20238D735 (7) | |
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hem States Power Company
. Training Center 1660 Wakonade Drive West Welch, MN 55086 June 22, 1987 Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406 Attention:
Mr. Noel F. Dudicy Reactor Engineer (Examiner)
Prairie Island Nuclear Generating Plant Docket Nos. 50-282 6 50-306
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License Nos. DPR-42 & DPR-60 Comments on NRC Administered SRO Written Examination Prairie Island has reviewed the Senior Reactor Operator requalification written examination administered on June 16, 1987.
Specific comments on the examination and answer key are listed below. Should you have any questions or I
comments, please contact us at (612) 388-1165.
Question 5.01 a
il The equation used in the answer key to solve the problem was not included in i
the equation sheet. We request that greater latitude be used in grading this part of the question.
Question 5.03(b)
Although the plant curves show Xenon returning to a 100% equilibrium value 26 I
hours after a trip, we teach that it reaches equilibrium 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after aCredit Ref erence, Westinghouse " Reactor Core Control", 7-13, attached.
trip.
should be given for "less than" with explanation.
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Question 5.05(a) j Although our training material discusses the effects of Samarium on shutdown l
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reactivity, the plant procedures assume the effects from Samarium are offset by the effects from Plutonium buildup and are not addressed in the procedures.
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i Samarium should not be required for full credit. Reference, Figurc CIA-2, attached.
8709110363 970904 PDR ADDCK 05000282 V
PDR Page 1 of 4 i
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i Question 5.07 The The setpoint for the low set steam generator safety valve is 1075 psig.
correct answer should be '4.13*F.
Reference, TS 2.2, attached.
Question 6.01 The setpoints listed in the reference used in the exam were original design setpoints. Since original operation, the setpoints have been adjusted to:
108 psig jockey pump start, 105 psig screenwash pump start, 100 psig motor driven fire pump start and 95 peig diesel driven fire pump start.
Ref erence, Logic Diagram NF-40318-1 & 3, attached.
Question 6.02 The system description (B-35) used as reference for this question is in error.
The third item listed on page 34 of B-35 should read " Loop A/B Cooling Water Header X-Over Valves A and B."
These valves are located in the Auxiliary Building and close on a SI signal from either unit, but are normally closed.
Reference, logic Diagram NF-40315-1, attached.
1 The answer key states that an acceptable answer is " Component Cooling pump starts on the unit which initiated the Sl."
The reference used for the answer (B-35, pp. 34) goes on to state that when the Component Cooling pump starts, the cooling water valve to the Component Cooling heat exchanger valve opens.
This valve opens on any Component Cooling pump start and is not a direct result of a S1 signal. This answer should not be required for credit.
Ref erence, Logic Diagram NF-30315-6, attached.
In addition to the actions listed in B-35, three other actions occur in the cooling water system due to a S1 signal. They are: The containment fan coil cooling water supply and return valves open, the containment f an coil cooling water return orifice bypass valves open, and the CRDM heat exchanger supply and return valves close. Reference, NF-40315-4, NE-40409-101 and NF-86186-4, attached.
A modification to B-35 has been initiated to correct the error, delete the misleading statement und add the other actions.
Question 6.03(c)
In addition to the interlocks in the system description, a breaker lockout signal must not be present for the breaker to close. This is a generic interlock to 4160V breakers, but is usually not discussed in the system The 86 lockout interlock should be added to the list of accept-description.
able answers. Electrical Schematic, NE-40005-32, is attached for your refer-ence.
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Question 7.01
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The answer key states "and wait 2 minutes", however, as indicated on the attached reference (B-18C, pp. 29), the time delay relay is set to 90 seconds.
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Question 7.03 Although the answers listed in the answer key are correct based on the refer-ence material, the examinees may focus on.the specifics of when they are not to trip RCPs. Specifically, if no S1 pumps are running and RCS pressure is greater then 1200 psig (1500 psig for adverse containment). Credit should be given for the response listed above. Reference, Emergency Procedure 1E-0, step 16, attached.
Question 7.04 Since The answer key requires a limit of 60 psig to be given in the answer.
the question did not state that setpoints were required, the value of 60 psig should not be required for full credit.
Question 8.03(a)
The answer key shows 2 R0s to be on the Unit 2 side of the control room.
Since Unit I has tripped, 2 R0s should be on the Unit 1 side. Although it is not clear from the answer key, the SR0s may be anywhere within the confines of the control room except behind the control board. Reference, SWI-0-2 page 2-3 and SW1-0-2 figure 2 and 3, attached.
Question 8.03(c)
In addition to the 2 centers listed in the answer key, the Operational Support Ccater (OSC)'and the Headquarters Emergency Center (HQEC) are also activated if an ALERT is declared. They should be added to the answer key. Reference.
F3-7, page 1 and Corporate Emergency Plan, section 5, page 1; attached.
Question 8.04(a)
If the switching involves the generator output breakers which are controlled from the control room, secure cards are attached to the switches. Therefore, the secure card book (log) should also be an acceptable answer.
Question 8.04(b)
Since this operation would involve opening and racking out of the motor J
breaker, hold cards would be hung on the breaker. Therefore, the hold card book (log) should also be an acceptable answer.
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Question 8.06(b)
The answer key lists tornado as a required response. The procedure states i
that a tornado must be sited by plant personnel and reported to the shif t supervisor to qualify as a NUE. This information was not given in the ques-tion. Tornado should not be required for full credit. Reference, Emergency Plan, chapter 4, page 44, attached.
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e Question 8.06(c)
The answer gives site ares emergency "due to a need for monitoring teams" as s
However, it is'not clear form the question that monitor-the required answer.
ing teams are required since there is no evidence of release or that one is The about to occur.- Monitoring teams may be dispatched at the ALERT level.
correct response is ALERT due to ECCS initiated and discharging to vessel, 50 gpm and severe loss of fuel
_ primary coolant leak rate greater than Reference, Emergency Plan, chapter 4, pages 5, 8 and 14, attached.
cladding.
Question 8.07(a)
At 02:00, the axial flux reading is -3.
The allowable band for axial flux is 15% of the target value. With a target of +3, the allowable axial flux would TS 3.10 be -2 to +8.
The axisi flux is out of the allowable band at 02:00.
allows the axial flux to be out of the band for no more than I hour in a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period. Since at 04:30 the axial flux is at -2, it has been out of the band for at least 2 1/2 hours. In this case, reactor power must be reduced to less than 50% and the high neutron flux setpoint reduced to less than 55% of rated power. Reference, TS 3.10-3, attached.
Question 8.07(b)
Since penalty minutes are accumulated on a one for one basis above 50% power, reactor power can be increased when less than 60 penalty minutes are accu-Depending on assumptions made about when axial flux returned to the mulated.
allowable band, power could be increased to 100% power approximately 03:30 the following day. Reference TS 3.10-4, attached.
Sincerely,
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e C. E. La on Vice President of Nuclear Generation CEL/ TEA /1rf Attachments T. Burdick, Region III; v/o attachments cc L
TEA-87-048
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bNraN[n e'n I 1660 Wakonade Drive West Welch, MN 55086 June 19, 1987 l
L Sonalysts Inc.
P.O. Box 280 215 Parkway North Waterford, Conn. 06385 Attention:
Mr. Frank Victor Prairie island Nuclear Generating Plant Docket Nos. 50-282 & 50-306 License Nos. DPR-42 & DPR-60 Comments on NRC Administered RO Written Examination Prairie Island has reviewed the Reactor Operator written requalification examination administered on June 16, 1987. Specific comments on the exam-ination and answer key are listed below. Should you have any questions or comments, please contact us at (612) 388-1165.
Question 1.03(a)
Nucleate boiling is most likely to occur when the temperature of the clad surfsce is near the critical heat flux. Onset of nucleate boiling is a function of several parameters including temperature, pressure and heat flux.
Generally this will occur first at 2/3 to 3/4 of the distance from the.,ottom of the core. Depending on how the examinee interprets top, bottom and center of the core, he may answer either top or center.. Center should be antaccept-able answer with explanation. Heat flux and pressure should be added to acceptable answers for why. Reference Page 3-73 of Westinghouse T-H Princi-ples and Figure 236 of Prairie Island Background information, attached.
Question 2.01 The system description (B-35) used as reference for this question is in error.
The third item listed on Page 34 of B-35 should read " Loop A/B Cooling Water Header X-Over Valves A and B."
These valves are located in the Auxiliary Building and close on a Si signal from either unit, but are normally closed.
Reference Logic Diagram NF-40315-1 attached.
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The answer key states that an acceptable answer is " Component Cooling pump f
starts on the unit which initiated the SI."
The reference used for the answer t
(B35 pp. 34) goes on to state that when the Component Cooling pump starts, the This cooling vater valve to the Component Cooling heat exchanger valve opens.
valve opens on any Component Cooling pump start and is not a direct result of a SI signal. This answer should not be required for credit. Reference Logic Diagram NF-30315-6, attached.
In addition to the actions listed in B35, three other actions occur in the cooling water system due to a SI signal. They are: The containment fan coil cooling water supply and return valves open, the containment f an coil cooling water return orifice bypass valves open, and the CRDM heat exchanger supply and return valves close. Reference, NF-40315-4, NE-40409-101 and NF-86186-4, attached.
A modification to B35 has been initiated to correct the error, delete the misleading statement and add the other actions.
Question 2.02(a)
Although the question may solicit the answer listed in the answer key, the examinees may also answer " Auto and Shutdown Auto" for the first part of the question since the pump will start automatically in either position. Refer-ence Logic Diagram NF-40312-1, attached.
Question 2.03(b)
In order to determine the correct response the examinee must interpret the question to mean, "Can the steam generator PORV be controlled in either auto or manual from both the control room and the hot shutdown panel?" The ques-tion is worded in such a way that the examinee may interpret the question to mean, "Can the steam generator PORV be operated in both auto and manual from the control room and be controlled from the hot shutdown panel?" If the examinee uses the second interpretation, the correct response is "true".
Either response should be acceptabic or the question should be deleted.
Question 2.04(c)
In addition to the interlocks listed in the system description, a breaker lockout signal must not be present for the breaker to close. This is'a generic interlock to 4160V breakers, but is usually not discussed in the system description. The 86 lockout interlock should be added to the list of acceptable answers. Electrical schematic, NE-40005-32, is attached for your reference.
Question 2.08 The question does not ask for setpoints which are listed in the answer key.
They should not be required for full credit.
In addition, the pressure setpoints are adjusted periodically for efficient system operation. The setpoints listed in the logic diagram are 95 and 100 psig. Reference Logic Diagram NF-40313-1, attached.
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I9 s tr Question 3.04(a)
The answer key lists power range NI as an input to P7.
Another way this may be answered is that P10 is an input to P7.
Reference X-HIAW-1-238, attached.
Question 3.05(a)
The answer key lists RCS pressure as an input into the OTAT setpoint. A more accurate statement is pressurizer pressure. Credit should be given for either response. Reference TS 2.3, attached.
Question 3.05(c)
The question asks for 2 protection or control functions other than reactor l
1 trip provided by OTAT, but the answer key requires turbine runback, auto rod withdrawal block and manual rod withdrawal block. Full credit should be given f
for turbine runback and rod stop.
1 Question 3.06 The answer key lists trips related to the 20/AST-1 solenoid only.
In addition to this solenoid, the 20-ET, 20-ET backup, 20-1 OPC and 20-2 OPC solenoid valves also trip the turbine. The trips listed in the attached reference (B-23 pp. 8-11) should be included in the answer key.
Question 4.01 Prairie Island job and task analysis does not indicate that memorization of instructions from normal operating procedures be required. We request that greater latitude be used in grading this question.
Question 4.06(c)
The question is written in such a way as to make the examinee think he should answer how he could adjust the emergency boration flow rate. Credit should be given for such answers as: adjust VCT pressure, change charging pump speed and adjust recirculation valve.
Sincerely, h m
C. E. Lar Vice President of Nuclear Generation 1
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Attachments cc:
T. Burdick, Region III; w/o attachments l
TEA-87-045 l
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