IR 05000237/2006301
| ML060750720 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 03/16/2006 |
| From: | Hironori Peterson Division of Reactor Safety III |
| To: | Crane C Exelon Generation Co, Exelon Nuclear |
| References | |
| 50-237/06-301, 50-249/06-301 50-237/06-301, 50-249/06-301 | |
| Download: ML060750720 (14) | |
Text
rch 16, 2006
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 NRC INITIAL LICENSE EXAMINATION REPORT 05000237/2006301(DRS);
Dear Mr. Crane:
On February 10, 2006, the NRC completed initial operator licensing examinations at your Dresden Nuclear Power Station. The enclosed report documents the results of the examination which were discussed on February 10, 2006, with Mr. D. Bost and other members of your staff. A subsequent telephone conversation was conducted on February 27, 2006, with Mr. C. Symonds and other members of your staff to discuss the NRCs resolution of the written examination post-examination comments.
NRC examiners administered the operating test during the week of February 6, 2005. Members of the Dresden Nuclear Power Station Training Department staff administered the written examination on February 13, 2006. Five Senior Reactor Operator (SRO) applicants were administered license examinations. The results of the examinations were finalized on March 1, 2006. Four applicants passed all sections of their examinations, two of these applicants were issued senior operator licenses. One SRO applicant failed the written examination and will not be issued a license. Two applicants scored either less than an 82 percent overall or 74 percent on the SRO only portion of the written examination; and, in accordance with the guidelines of NUREG 1021, Operator Licensing Examination Standards for Power Reactors, ES-501.D.3.c, these licenses will be withheld until any appeal rights of the failed applicant are exhausted.
In accordance with 10 CFR Part 2.390 of the NRC's Rules of Practice, a copy of this letter and its enclosure will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room). We will gladly discuss any questions you have concerning this examination.
Sincerely,
/RA/
Hironori Peterson, Chief Operations Branch Division of Reactor Safety Docket Nos. 50-237; 50-249 License Nos. DPR-19; DPR-25
Enclosures:
1. Operator Licensing Examination Report 05000237/2006301(DRS); 05000249/2006301(DRS)
2. Simulation Facility Report 3. Post Examination Comments and Resolutions 4. Written Examinations and Answer Keys (RO & SRO)
REGION III==
Docket Nos: 50-237; 50-249 License Nos: DPR-19; DPR-25 License No.: DPR-43 Report No.: 000237/2006301(DRS); 05000249/2006301(DRS)
Licensee: Exelon Generation Company Facility: Dresden Nuclear Power Station Location: 6500 North Dresden Road Morris, IL 60450 Dates: February 6 through February 10, 2006 Examiners: C. Phillips, Chief Examiner C. Zoia, Examiner Approved by: H. Peterson, Chief Operations Branch Division of Reactor Safety Enclosure 1
SUMMARY OF FINDINGS
ER 05000237/2006301(DRS); 05000249/2006301(DRS); 02/06/2006-02/10/06; Dresden
Nuclear Power Station; Initial License Examination Report.
The announced operator licensing initial examination was conducted by regional examiners in accordance with the guidance of NUREG-1021, Operator Licensing Examination Standards for Power Reactors, Revision 9.
Examination Summary:
- Five Senior Reactor Operator examinations were administered.
- Four applicants passed all sections of their examinations, two of these applicants were issued senior operator licenses. One SRO applicant failed the written examination and will not be issued a license. Two applicants scored either less than 82 percent overall or less than 74 percent on the SRO only portion of the written examination; and, in accordance with the guidelines of NUREG 1021, Operator Licensing Examination Standards for Power Reactors, ES-501.D.3.c, these licenses will be withheld until any appeal rights of the failed applicant are exhausted.
REPORT DETAILS
OTHER ACTIVITIES (OA)
4OA5 Other
.1 Initial Licensing Examinations
a. Examination Scope
The NRC examiners conducted an announced initial operator licensing examination during the week of February 6, 2006. The licensee used the guidance established in NUREG-1021, Operator Licensing Examination Standards for Power Reactors, Revision 9, to prepare the examination outline and to develop the written examination and operating test. The NRC examiners administered the operating test February 6 through 10, 2005. Members of the Dresden Nuclear Power Station Training Department administered the written examination on February 13, 2006. Five Senior Reactor Operator (SRO) applicants were examined.
b. Findings
Written Examination The licensee developed the written examination. During their internal review, the NRC examiners determined that the examination, as submitted, was within the range of acceptability expected for a proposed examination. Written examination comments developed during review by the NRC staff, and as a result of examination validation were incorporated into the written examination in accordance with the guidance contained in NUREG-1021.
A total of two post-examination comments on the reactor operator portion of the examination were submitted by the applicants and station training department personnel on February 17, 2006. The results of the NRCs review of the comments are documented in Attachment 3, Post Examination Comments and Resolutions.
Operating Test The NRC examiners determined that the operating test, as originally submitted by the licensee, was within the range of acceptability for a proposed examination. The examiners validated the operating test during the validation week and replaced or modified several items in the proposed operating test. Test changes, agreed upon between the NRC and the licensee, were made in accordance with NUREG-1021 guidelines.
Examination Results Four applicants passed all sections of their examinations, two of these applicants were issued senior operator licenses. One SRO applicant failed the written examination and will not be issued a license. Two applicants scored either less than 82 percent overall or less than 74 percent on the SRO only portion of the written examination; and, in accordance with the guidelines of NUREG 1021, Operator Licensing Examination Standards for Power Reactors, ES-501.D.3.c, these licenses will be withheld until any appeal rights of the failed applicant are exhausted.
.2 Examination Security
a. Inspection Scope
The NRC examiners briefed the facility contact on the NRCs requirements and guidelines related to examination physical security (e.g., access restrictions and simulator considerations). The examiners observed the implementation of examination security and integrity measures (e.g., security agreements) throughout the examination process.
b. Findings
No findings were noted in this area. There was one observation made by the examiners during the on-site validation week. The licensed operators performing the validation were using radios to communicate with the simulator booth. The examiners verified that there were only two radios and that they had a different frequency than those radios available to the operators in the plant. The examiners also verified that transmissions from the building could easily be received in the parking lot. The examiners concern was that the capability existed to listen to the transmissions with a radio scanner from the parking lot. The licensee documented this concern in Issue Report 440959.
Licensee management stated that in the future operators validating the examination would use the internal phone system instead of the radios.
4OA6 Meetings
.1 Exit Meeting
The chief examiner presented the examination team's preliminary observations and findings on February 10, 2006, to Mr. D. Wozniak and other members of the Operations and Training Department staff. A subsequent exit via teleconference was held on February 27, 2006, with Mr. C. Symonds following review of the site post-examination comments. The licensee acknowledged the observations and findings presented. No proprietary information was identified by the stations staff during the exit meetings.
ATTACHMENT:
SUPPLEMENTAL INFORMATION
Enclosure 1
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- D. Wozniak, Plant Manager
- R. Gadbois, Operations Director
- A. Khanifar, Nuclear Oversight Manager
- C. Symonds, Training Director
- G. Graff, Operations Training Director
NRC
None.
ITEMS OPENED, CLOSED, AND DISCUSSED
Opened, Closed, and Discussed
None
LIST OF ACRONYMS USED
ADAMS Agency-Wide Document Access and Management System
DRS Division of Reactor Safety
NRC Nuclear Regulatory Commission
PARS Publicly Available Records
RO Reactor Operator
SRO Senior Reactor Operator
Attachment
SIMULATION FACILITY REPORT
Facility Licensee: Dresden Nuclear Power Station
Facility Docket No.: 50-237; 50-249
Operating Tests Administered: February 6-10, 2006
The following documents observations made by the NRC examination team during the initial
operator license examination. These observations do not constitute audit or inspection findings
and are not, without further verification and review, indicative of non-compliance with
CFR 55.45(b). These observations do not affect NRC certification or approval of the
simulation facility other than to provide information which may be used in future evaluations. No
licensee action is required in response to these observations.
During the conduct of the simulator portion of the operating tests, the following item was
observed:
ITEM DESCRIPTION
A problem was noted with the use of the 2/3A Standby Gas Treatment
Train. When attempting to restart the 2/3A Standby Gas Treatment
Standby Gas Train after a simulated Group II isolation the A train heater repeatedly
Treatment turned itself on and off and the A train flow fluctuated significantly. The
licensee was unable to repair the simulator so that it could consistently
perform as expected. The JPM was replaced.
Post-Examination Comments and Resolution
Question Number 8.
A small steam leak has developed in the Unit 2 Drywell and the following conditions exist:
RPV level is +30" and steady
- Both loops of Torus Sprays are on
- Torus Cooling is on using both divisions
- 316A and 316B switches are in Manual Override
- Drywell pressure is +5 psig and trending down slowly
If Drywell pressure drops below 1 psig, THEN:
A. the LPCI system will continue to operate as stated above.
B. the Torus spray valves in both LPCI loops will auto close.
C. the Torus cooling valves in both LPCI loops will auto close.
D. the LPCI inboard injection valve (21A or B) on the "Non-Selected" LPCI loop will auto
close.
Answer: B
Applicant Comment:
Torus spray valves will not close when Drywell pressure drops below 1 psig as long as level is >
- 59 inches. The Drywell +2 psig drywell pressure signal does not seal in.
Facility Proposed Resolution:
The facility management agreed with the applicants statement. The original question was
written with the premise that the LPCI [low pressure core injection] initiation was a seal-in logic.
The original conditions have drywell pressure at + 5 psig. When conditions change and drywell
pressure drops to + 1 psig, a valid LPCI initiation signal is no longer present, so the spray
valves will not close automatically.
Electrical prints 12E-2437 sh 1 and 2, and 12E-2441 sh 1 have been submitted to the NRC to
support the challenge. The two relays for making this determination are the BD-124 and the
CR-138. Both of the relays have contacts in the Torus Spray Valve Logic. The basis for the
correct answer being A, is that the pressure switches that feed the BD-124 relay are set to
drop out at 1.81 psig decreasing and the pressure switches for the one pound interlock to the
CR-138 relay are set at 1.5 psig. Because of these setpoints and the fact that the logic is not
seal-in, the closed contact in the Torus Spray logic will not be made up.
NRC Resolution:
Upon review of the question, the applicant comment, and the facility proposed resolution it was
decided to change the correct answer from B to A. Based on the plant conditions given in
the question stem there is no LPCI injection signal present at the time that the drywell pressure
drops below + 1 psig. After a review of the electrical drawings supplied by the licensee the
Chief Examiner verified that the LPCI initiation signal does not seal-in and therefore there is no
signal generated to close the torus spray valves.
The Chief Examiner reviewed the licensees response from the perspective that if the licensees
response was correct than valve 2-1501-18A, which was open, would not change position.
Electrical prints 12E-2437 sh 1 and 2, and 12E-2441 were reviewed. There are two contacts in
series that must close, in the close control circuit for valve 2-1501-18A, for the valve to change
position and close. There is a B contact from relay CR-138 and an A contact from relay
BD-124. For these contacts to close, and therefore energize the closing circuit for 2-1501-18A,
the CR-138 relay would have to de-energize and the BD-124 relay would have to remain
energized.
For BD-124 to energize two A contacts in series from relays DG-108 and DF-109 must close.
To energize relays DG-108 and DF-109 contacts from high drywell pressure switches PS-1632A
and PS-1632C must close. The contacts from these pressure switches close, per the Technical
Specifications, at less than or equal to 1.81 psig increasing. These contacts will open when the
presure switches reset at greater than or equal to 1.6 psig decreasing.
Therefore, with reactor water level greater than -59 inches as drywell pressure decreases below
1.6 psig relays DG-108 and DF-109 de-energize and the associated A contacts open. When
these contacts open then relay BD-124 will de-energize. When relay BD-124 de-energizes then
the associated A contacts in the closing circuit for 2-1501-18A will open and the valve will not
reposition. This would make A the correct answer.
During a review of the Dresden UFSAR Section 7.4.1 the examiners identified that UFSAR
stated: To initiate or maintain drywell and/or torus spray, drywell pressure must be above the
low limit setpoint. The examiners discussed this inconsistency between the UFSAR and the
electrical drawings with Dresden Station Management. The licensee generated Issue Report
459346 to determine the cause for and correct the inconsistency in the UFSAR. The licensee
also tested the above scenario on the Dresden Simulator on February 27, 2006. The simulator
behaved as described in the electrical drawings mentioned above. The spray valves did not
shut as drywell pressure dropped below 1 psig with reactor water level above -59 inches. The
validated the correct answer for Question 8 as A.
Question Number 73.
Given the following:
- Unit 2 was at rated power
- CHANNEL 'A' AND 'B' MN STM TUNN TEMP HI annunciators alarm
- All other automatic plant systems function as designed
What would be the expected Reactor PEAK Pressure?
A. 1070
B. 1110
C. 1144
D. 1250
Answer: C
Applicant Comment:
Per GE-NE-A22-00103-10-01 (Dresden and Quad Cities Extended Power Uprate), MSIV
closure direct scram transient results are listed in Table 3-2. Peak steam dome pressure for
100% power and 95% recirculation flow is listed as 1140.6 psig and peak vessel pressure as
1173.0 psig.
Facility Proposed Resolution:
Remove the question from the exam as none of the four possible answers reflects the current
value. The original question was written using the UFSAR Revision 3 for Dresden Station,
Section 15.2.4.1.3. The correct answer per this document is 1144 psig. During the exam it was
identified that General Electric had performed a new analysis, Extended Power Uprate. Per
GE-NE-A22-00103-10-01 Dresden and Quad Cities Extended Power Uprate table 3-2 Peak
Steam Dome Pressure for the conditions given would be 1140.6 psig. This was not one of the
possible answers for the candidates.
NRC Resolution:
The Chief Examiner reviewed the Dresden UFSAR Revision 5 and GE-NE-A22-00103-10-01
Dresden and Quad Cities Extended Power Uprate table 3-2. The answer given in the exam was
for the previous power level. For the current licensed power level the values given in the
General Electric report are valid and were not one of the choices given in the question.
Therefore the Chief Examiner concurs with the licensees conclusion that there was no correct
answer available and the question will be removed from the examination.
WRITTEN EXAMINATIONS AND ANSWER KEYS (RO/SRO)
RO/SRO Initial Examination ADAMS Accession # ML060760307.