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Reactor Physics Nuclear Engineer

Date: Sep 14, 2021

Location: Oak Ridge, TN, US, 37830

Company: Oak Ridge National Laboratory

Requisition Id 6561 


The Nuclear Safety and Experiment Analysis (NSEA) Group’s Reactor Analysis and Modeling Team within the Research Reactors Division (RRD), Neutron Sciences Directorate (NScD) seeks applications for the Reactor Physics Nuclear Engineer position at the High Flux Isotope Reactor. We are seeking a highly motivated reactor physics analyst who is comfortable working in a team environment, with collaboration at all levels, disciplines, and diverse cultural backgrounds, both inside and outside the organization. The successful candidate should have a strong background in nuclear reactor physics and an interest in a variety of nuclear engineering disciplines.


Major Duties and Responsibilities:

  • Support nuclear safety and experiment analysis activities, scientific research projects, and the safe, reliable, and efficient operation of HFIR through reactor physics analyses and engineering evaluations
  • Perform HFIR modeling, simulation, and analysis activities using reactor physics codes, such as MCNP, SCALE, HFIRCON, Shift, VESTA, and ADVANTG and review similar calculations performed by others
  • Work with the experiment team and users to support scientific missions, such as isotope production (e.g., 238Pu, 252Cf), materials irradiation, neutron activation analysis, and gamma irradiation
  • Collaborate on high-enriched uranium to low-enriched uranium fuel conversion project activities, such as core design and performance optimization studies
  • Perform analysis in support of the HFIR capability enhancement project
  • Perform reactor startup evaluations, such as beginning-of-cycle control element position calculations and neutron source requirement evaluations
  • Perform analysis and calculations using computer clusters and simulation codes, including software quality assurance activities
  • Analyze HFIR fuel element reactor physics effects of design changes and supplier nonconformances
  • Perform safety analyst role for assigned systems, such as fuel and control elements, including evaluations through the Unreviewed Safety Question (USQ) process
  • Collaboratively work with RRD NSEA Nuclear Safety, Reactor Analysis and Modeling, and Experiment Analysis and Coordination teams; others within RRD (e.g., Systems Engineering, Operations); and other ORNL directorates and divisions to support RRD and ORNL missions
  • Thoroughly document and present work performed to meet project deliverables
  • Ensure technical compliance with 10CFR830 Subparts A and B, affecting reactor safety, through implementation of ORNL Standards Based Management System (SBMS) and RRD procedures
  • Ensure adherence to the rules and regulations that govern the operation of a DOE nuclear facility and ensure compliance with environment, safety, health, and quality program requirements
  • Maintain a strong commitment to nuclear safety
  • Publish technical reports and research papers related to HFIR reactor physics in support of the HFIR documented safety analysis and ORNL and Neutron Sciences Directorate missions.
  • As a member of the ORNL scientific community, you will be expected to commit to ORNL's Research Code of Conduct.  Our full code of conduct, and a statement by the Lab Director's office can be found here:   


Basic Qualifications:

  • Master’s degree in nuclear engineering, engineering physics, or a related technical field with five years of relevant experience, or a Ph.D. degree with two years of relevant experience
  • Possess a strong reactor physics analysis background as demonstrated through graduate thesis research, publications, and/or work experience
  • Must be organized, detail-oriented, and sensitized to a nuclear safety culture
  • Demonstrated results-oriented problem-solving skills and a willingness to apply those skills to a variety of engineering problems
  • Excellent communication skills, including verbal, presentation, and writing skills
  • Capability to successfully function both independently and in small-to-moderate size teams


Other Job Requirements:
This position requires the ability to obtain and maintain a DOE “L” clearance.


This position is a Workplace Substance Abuse program (WSAP) testing designed position which requires passing a pre-placement drug test and participation in an ongoing random drug testing program in which employees are subject to being randomly selected for testing. The occupant of this position will also be subject to an ongoing requirement to report to ORNL any drug-related arrest or conviction or receipt of a positive drug test result.


Preferred Qualifications:

  • An advanced degree
  • Experience with neutron transport codes, such as MCNP, Shift, SCALE, and ADVANTG
  • Experience with fuel cycle depletion codes, such as VESTA, Shift, and SCALE
  • Familiarity and experience with research reactors
  • Experience with other reactor engineering disciplines, such as dispersion analysis, thermal-hydraulics, thermal-structural interaction, materials science, or probabilistic risk assessment
  • Experience with LINUX or LINUX-like environments and scripting/computer languages, such as MATLAB, Python, and Fortran
  • Familiarity and experience with 10CFR830 Subparts A and B and the USQ process


About Neutron Sciences Directorate:
The Neutron Sciences Directorate (NScD) at Oak Ridge National Laboratory (ORNL) operates the High Flux Isotope Reactor (HFIR), the United States' highest flux reactor-based neutron source, and the Spallation Neutron Source (SNS), the world's most intense pulsed accelerator-based neutron source. Together, these facilities operate over 30 instruments for neutron scattering research, each year carrying out an excess of 1,000 experiments in the physical, chemical, materials, biological and medical sciences. HFIR also provides unique facilities for isotope production and neutron irradiation. To learn more about Neutron Sciences at ORNL go to:

Benefits at ORNL:

UT Battelle offers an exceptional benefits package to include matching 401K, Pension Plan, Paid Vacation and Medical / Dental plan. Onsite amenities include Credit Union, Medical Clinic and free Fitness facilities.



Moving is stressful and expensive, and UT Battelle offers a wide range of relocation benefits for individuals and families to make it easier to come and work here. If you are invited to interview, please ask your Recruiter about relocating with ORNL.



This position will remain open for a minimum of 5 days after which it will close when a qualified candidate is identified and/or hired.

We accept Word (.doc, .docx), Adobe (unsecured .pdf), Rich Text Format (.rtf), and HTML (.htm, .html) up to 5MB in size. Resumes from third party vendors will not be accepted; these resumes will be deleted and the candidates submitted will not be considered for employment.

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ORNL is an equal opportunity employer. All qualified applicants, including individuals with disabilities and protected veterans, are encouraged to apply.  UT-Battelle is an E-Verify employer.

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