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Initial Examination Report No. 50-005/OL-13-01, Pennsylvania

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Initial Examination Report No. 50-005/OL-13-01, Pennsylvania September 3, 2013 Dr. Kenan Unlu, Director Radiation Science and Engineering Center Breazeale Nuclear Reactor Building Pennsylvania State University University Park, PA 16802-2301 SUBJECT: EXAMINATION REPORT NO. 50-005/OL-13-01, PENNSYLVANIA STATE UNIVERSITY BREAZEALE RESEARCH REACTOR Dear Dr. Unlu: During the week of August 12, 2013, the U.S. Nuclear Regulatory Commission (NRC) administered operator licensing examinations at your Breazeale Nuclear Reactor. The examinations were conducted according to NUREG-1478, “Operator Licensing Examiner Standards for Research and Test Reactors,” Revision 2. Examination questions and preliminary findings were discussed at the conclusion of the examination with those members of your staff identified in the enclosed report. In accordance with Title 10, Section 2.390 of the Code of Federal Regulations, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRC’s Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room). The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. If you have any questions concerning this examination, please contact Mr. Gregory M. Schoenebeck at (301) 415-6345, or via e-mail at [email protected]. Sincerely, /RA/ Gregory T. Bowman, Chief Research and Test Reactors Oversight Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No.: 50-005 Enclosures: 1. Examination Report No. 50-005/OL-13-01 2. Facility Comments with NRC Resolution 3. Written examination with facility comments incorporated cc: Mark Trump, Associate Director for Operations w/o enclosures: See next page September 3, 2013 Dr. Kenan Unlu, Director Radiation Science and Engineering Center Breazeale Nuclear Reactor Building Pennsylvania State University University Park, PA 16802-2301 SUBJECT: EXAMINATION REPORT NO. 50-005/OL-13-01, PENNSYLVANIA STATE UNIVERSITY BREAZEALE RESEARCH REACTOR Dear Dr. Unlu: During the week of August 12, 2013, the U.S. Nuclear Regulatory Commission (NRC) administered operator licensing examinations at your Breazeale Nuclear Reactor. The examinations were conducted according to NUREG-1478, “Operator Licensing Examiner Standards for Research and Test Reactors,” Revision 2. Examination questions and preliminary findings were discussed at the conclusion of the examination with those members of your staff identified in the enclosed report. In accordance with Title 10, Section 2.390 of the Code of Federal Regulations, a copy of this letter and the enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records component of NRC’s Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room). The NRC is forwarding the individual grades to you in a separate letter which will not be released publicly. If you have any questions concerning this examination, please contact Mr. Gregory M. Schoenebeck at (301) 415-6345, or via e-mail at [email protected]. Sincerely, /RA/ Gregory T. Bowman, Chief Research and Test Reactors Oversight Branch Division of Policy and Rulemaking Office of Nuclear Reactor Regulation Docket No. 50-005 Enclosures: 1. Examination Report No. 50-005/OL-13-01 2. Facility Comments with NRC Resolution 3. Written examination with facility comments incorporated cc: Mark Trump, Associate Director for Operations w/o enclosures: See next page DISTRIBUTION: PROB r/f RidsNrrDprProb RidsNrrDprPrlb ADAMS Accession No: ML13239A334 OFFICE NRR/DPR/PROB NRR/DPR/PROB NRR/DPR/PROB NAME GSchoenebeck CRevelle GBowman DATE 08/28 /2013 08/30/2013 09/03/2013 OFFICIAL RECORD COPY Pennsylvania State University Docket No. 50-005 cc: Mr. Eric J. Boeldt, Manager of Radiation Protection The Pennsylvania State University 304 Old Main University Park, PA 16802-1504 Dr. Eva J. Pell Vice President and Dean of the Graduate School Pennsylvania State University 304 Old Main University Park, PA 16802-1504 Director, Bureau of Radiation Protection Department of Environmental Protection P.O. Box 8469 Harrisburg, PA 17105-8469 Test, Research, and Training Reactor Newsletter University of Florida 202 Nuclear Sciences Center Gainesville, FL 32611 U. S. NUCLEAR REGULATORY COMMISSION OPERATOR LICENSING INITIAL EXAMINATION REPORT REPORT NO.: 50-005/OL-13-01 FACILITY DOCKET NO.: 50-005 FACILITY LICENSE NO.: R-2 FACILITY: Pennsylvania State University Breazeale Nuclear Reactor EXAMINATION DATES: August 12 – August 15, 2013 SUBMITTED BY: ___________/RA/___________ _08/29/13_ Gregory M. Schoenebeck Date SUMMARY: During the week of August 12, 2013, the NRC administered operator licensing examination to one Senior Reactor Operator (SRO) and seven Reactor Operator (RO) license candidates. The entire license candidates passed all applicable portions of the examinations. REPORT DETAILS 1. Examiners: Greg M. Schoenebeck, Chief Examiner, NRC 2. Results: RO PASS/FAIL SRO PASS/FAIL TOTAL PASS/FAIL Written 7/0 N/A 7/0 Operating Tests 7/0 1/08/0 Overall 7/0 1/08/0 3. Exit Meeting: Gregory M. Schoenebeck, Chief Examiner, NRC Paulette Torres, Reactor Engineer, NRC Mark Trump, Associate Director for Operations Dr. Kenan Unlu, Director At the conclusion of the site visit, the examiner met with representative of the facility staff to discuss the results of the examinations. The facility licensee had three comments on the written examination recommending changing the answer key on question A.7, A.18 and C.1 (see Enclosure 2). ENCLOSURE FACILITY COMMENTS ON THE WRITTEN EXAM WITH NRC RESOLUTION QUESTION A.7 [1.0 point] An experiment worth 13 cents of negative reactivity is added to a reactor that is initially critical at a power of 1000 Watts. Assuming there is no automatic system response, operator action, or any other reactivity effects, calculate the power level 2 minutes after the reactivity insertion. Given: βeff= 0.0070 -1 λeff= 0.05 sec a. 2 Watts b. 406 Watts c. 500 Watts d. 750 Watts Answer: a Reference: Burn, R., Introduction to Nuclear Reactor Operations, ©1988, § 3.4.1 Given: βeff= 0.0070 -1 λeff= 0.05 sec = First, converting negative $0.13 to ∆k/k -0.13*0.0070= -0.00091 (0.007-(-0.00091))/((0.05)*(-0.00091))= -173.4 sec = 1000 e (120/-173) = 499.7 Watts or 500 Watts Facility Comment: The facility stated that the answer key correctly calculates the power at 2 minutes as being 499.7 Watts (answer C), however lists letter A (2 Watts) as the correct answer. The answer key should be changed to: C (500 Watts) NRC Resolution: The NRC agrees with the facility comment and accepts c as the correct answer. ENCLOSURE 2 - 2 - QUESTION A.18 [1.0 point] The PSBR has what is known as a prompt negative temperature coefficient. Which of the following is the largest contributing factor to the prompt negative temperature coefficient? a. Doppler effect b. Compton’s Scattering c. Cell effect d. Core Leakage Answer: d Reference: PSBR Training Manual, Chapter 3 Appendix A.10 Facility Comment: The facility stated that the answer key references the PSBR Training Manual, Chapter 3 Appendix A.10. According to this reference, 15% of the prompt negative temperature coefficient is caused by Doppler effect, 65% by cell effect, and 20% by core leakage. The answer key lists d (core leakage) as the correct answer. The answer key should be changed to c (cell effect). NRC Resolution: The NRC agrees with the facility comment and accepts c as the correct answer. - 3 - QUESTION C.1 [1.0 point] When the ventilation system is in the emergency exhaust mode _____________. a. air outside of the PSBR facility is pulled into the emergency exhaust system through a screened opening in the east wall of the reactor bay to dilute the filtered air that is ultimately released through the 18” PVC Emergency Exhaust Stack which terminates above the main Reactor Bay roof. b. air outside of the PSBR facility is pulled into the emergency exhaust system and a DCC-X message “Emerg Ventilation Flow On” can be observed by the Reactor Operator which is the most positive indication that the system has flow. c. filtered air is recirculated in the reactor bay to prevent the potential release of fission products to the environment. d. filtered air is ultimately released through the 18” PVC Emergency Exhaust Stack which terminates above the main Reactor Bay roof. Answer: a Reference: PSBR Training Manual, Chapter 5.3.4.3 Facility Comment: Answer Key should be changed to “d” the correct Answer. Analysis: a. Incorrect EES pulls only from the screened opening on the east wall reactor bay, the air released from the Exhaust stack is not diluted, only filtered. b. Incorrect no outside air is pulled into EES. All air discharged by the EES during operation originates from within the reactor bay. c. Incorrect no recirculation occurs filtered air is discharged above the main reactor bay roof d. Correct – Filter air is released from the EES exhaust stack above the reactor bay roof level NRC Resolution: The staff agrees with the facility’s comment. The answer key will be modified to accept “d” as the correct answer for question C.1. U. S. NUCLEAR REGULATORY COMMISSION NON-POWER REACTOR INITIAL LICENSE EXAMINATION FACILITY: PENN STATE UNIVERSITY REACTOR TYPE: POOL TYPE, MODIFIED TRIGA DATE ADMINISTERED: CANDIDATE: ___________________________________ INSTRUCTIONS TO CANDIDATE: Answers are to be written on the answer sheet provided. Attach the answer sheets to the examination. Points for each question are indicated in parentheses for each question. A 70% overall is required to pass the examination. Examinations will be picked up three (3) hours after the examination starts.
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