Nuclear Criticality Safety Engineer

X-energy; Oak Ridge (TN); On-site; USD 93,000 - 186,000; Full time

Benefits offered by this job

401K with employer match

Medical/Dental/Vision insurance

Life and Disability Insurance

Paid Time Off

Tuition Reimbursement/Professional Dev

Job summary

X Energy, LLC in Oak Ridge, TN, seeks a Nuclear Criticality Safety Engineer to ensure safe handling of fissile materials and NRC compliance across TRISO-X operations. The role spans design support through daily operations and involves developing safety basis evaluations and ISA support.

You will perform NCS calculations, lead Process Hazards Analysis activities, train staff, and mentor Level II–IV engineers while advancing ISA documentation and safety controls.

Qualifications

• Bachelor’s degree in a STEM field from ABET-accredited college/university.
• Level II: ~3+ years in nuclear criticality safety with safety basis evaluations.
• Experience using SCALE/MCNP or similar NCS codes to demonstrate subcriticality.
• Ability to qualify under ANSI/ANS-8.26-2007 training program.
• Level III: ~5+ years in NCS with safety basis evaluations.
• Level IV: ~10+ years in NCS; ISA Risk Assessments & Process Hazards analysis lead.
• Experience with regulatory requirements, standards, and guidance.

Responsibilities

• Define safety basis for fissile material operations; monitor IROFS, limits, controls and barriers.
• Develop/review NCS evaluations to demonstrate subcriticality for processes and facility operations.
• Develop/review calculations using NCS codes and models.
• Lead/participate in Process Hazards Analysis with multidisciplinary teams.
• Evaluate accident sequences and ISA risk assessments; identify IROFS.
• Advise operations on NCS impacts of changes to processes and facility designs.
• Participate in design reviews; conduct surveillances and audits.
• Develop/revise NCS training and postings for administrative controls.
• Support the emergency response team.

Skills

Subcriticality analyses

NCS guidance

Hazard analysis

Education

ABET-accredited STEM degree

Tools

SCALE

MCNP

Job description

X-energy LLC conducts a thorough recruiting process and will never issue offers without interview to discuss qualifications and responsibilities. If anyone claiming to represent X-energy directs you in a manner otherwise, please contact us at www.x-energy.com/contact-us.

Job Description

This role is responsible for providing technical capabilities in Nuclear Criticality Safety (NCS) to ensure TRISO-X Fuel Fabrication Facility fissile materials are processed, stored, and handled safely to prevent an inadvertent nuclear criticality, and personnel and the public/environment are protected in accordance with Nuclear Regulatory Commission (NRC) requirements in 10 CFR 70. This role will transition from design/licensing support through start-up/commissioning to supporting day-to-day facility operations.

Job Profile Tasks/Responsibilities

• Define the safety basis for fissile material operations by evaluating and analyzing equipment, processes, and procedures; implement and facilitate NCS programs and procedures; and monitor the effectiveness of NCS items relied on for safety (IROFS), limits, controls, and barriers.
• Develop/review/revise NCS evaluations to demonstrate subcriticality for normal operations and process upsets of TRISO-X fuel fabrication processes and TRISO-X Facility operations, including processes involved in producing TRISO fuel forms, quality control activities, recycling/recovery of process materials, managing effluents and waste materials, and conducting maintenance activities.
• Develop/review/revise calculations by executing NCS computer codes and models to support NCS evaluations.
• Participate in and/or facilitate Process Hazards Analysis activities with multidiscipline teams to identify potential criticality, radiological, chemical, and fire/explosion hazards to support the Integrated Safety Analysis (ISA) process.
• Evaluate accident sequences to determine limits and controls necessary to demonstrate double contingency and perform ISA risk assessment to identify IROFS to ensure a criticality is highly unlikely.
• Consult with and advise operations, maintenance, and engineering personnel on the NCS impacts of new or proposed changes to processes, procedures, and facility designs/modifications.
• Participate in design reviews.
• Conduct surveillances, inspections, walk-downs, investigations, and audits/assessments of fissile material operations, and unusual incidents to ensure compliance with approved procedures and safety bases.
• Develop/revise/deliver NCS training to operations, maintenance, and other personnel.
• Develop/revise NCS postings and operator aids to implement administrative controls to ensure they are unambiguous, easily understood, and readily achievable.
• Provide support to the emergency response team.
• Maintain professional demeanor and behavior at all times in all forms of communication.
• Perform other duties as assigned by manager.
• Level II: Support team members with the execution of the core tasks and responsibilities listed in the Job Profile Task/Responsibilities section of this document
• Level III: Execute the core tasks and responsibilities listed in the Job Profile Task/Responsibilities section of this document.
• Level IV: Lead the execution of the core tasks and responsibilities listed in the Job Profile Task/Responsibilities section of this document.
• Provide feedback and guidance to more junior team members with the execution of the core tasks and responsibilities listed in the Job Profile Task/Responsibilities section of this document.

Job Profile Minimum Qualifications

• Bachelor’s degree in any STEM related field from an ABET-accredited college or university.
• Level II: Typically, three plus years of experience in the nuclear criticality safety field with preparing, reviewing, and/or revising safety basis evaluations that identify and document NCS limits and controls.
• Experience using SCALE, MCNP, or other NCS computer codes and models to demonstrate subcriticality.
• Ability to become qualified under a formal training and qualification program consistent with guidelines presented in ANSI/ANS-8.26-2007, Criticality Safety Engineer Training and Qualification Program.
• Level III: Typically, five plus years of experience in the nuclear criticality safety field with preparing, reviewing, and/or revising safety basis evaluations that identify and document NCS limits and controls.
• Experience using SCALE, MCNP, or other NCS computer codes and models to demonstrate subcriticality.
• Ability to become qualified under a formal training and qualification program consistent with guidelines presented in ANSI/ANS-8.26-2007, Criticality Safety Engineer Training and Qualification Program.
• Working knowledge of relevant industry codes and standards for nuclear criticality safety in non-reactor facilities and operations. Understanding and experience applying regulatory requirements, standards, and guidance.
• Level IV: Typically, ten plus years of experience in the nuclear criticality safety field with preparing, reviewing, and/or revising safety basis evaluations that identify and document NCS limits and controls.Three years may be credited towards years of experience when successfully performing the following duties: Preparing and Reviewing ISA Risk Assessments, Leading Process Hazards Analysis, and Preparing ISA Summary documentation.
• Experience using SCALE, MCNP, or other NCS computer codes and models to demonstrate subcriticality.
• Ability to become qualified under a formal training and qualification program consistent with guidelines presented in ANSI/ANS-8.26-2007, Criticality Safety Engineer Training and Qualification Program.
• Working knowledge of relevant industry codes and standards for nuclear criticality safety in non-reactor facilities and operations. Understanding and experience applying regulatory requirements, standards, and guidance.

Location

150 Lafayette Dr., Oak Ridge TN 37830

Work Site Expectations: 5 days onsite

Travel Expectations

up to 10% or as needed

Hours

standard office schedule is 8:00am-5:00pm ET, Mon-Fri

Compensation

As required by Maryland and other applicable state law, X Energy, LLC (X-energy) lists the expected compensation range for a publicly advertised job opportunity based upon the job requirements (e.g. education/training, experience, skill sets, etc.). Individual candidates who meet the job requirements for the posted position will be offered a salary within this range based on their respective levels of education/training, experience, and other qualifications unique to them. Salary ranges may vary based on the specific office location and region referenced in the posting to take into consideration differences in cost of living and may not be reflective of all regions. Please note that compensation ranges listed for US job postings reflect base salary only and do not include benefits or other incentives.

Offers within the posted salary range are commensurate with the individual’s qualifications for the position, along with a view on internal equity, market data, and room for growth. The salary range for this position is:

Level II - $93,188 - $122,063/ Level III - $112,875 - $149,625/ Level IV - $139,125 - $186,375

Position Job Classification

Full time - Exempt

Benefits

X Energy, LLC offers a robust benefits package that includes a 401K plan with an employer match, Medical/Dental /Vision Insurance, Life and Disability Insurance, Paid Time Off, and a Tuition Reimbursement/Professional Development policy that supports the continuing education of our employees.

An Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.

X Energy, LLC participates in E-Verify. Please visit the links below for more information about E-Verify and the protection of your Right to Work.

Right To Work Link: If you have the right to work, don’t let anyone take it away (e-verify.gov)

E-Verify Participation Link: E-Verify Participation Poster English and Spanish