Criticality Safety Engineer

We have an opening for a Criticality Safety Engineer within the Environment Safety and Health (ES&H) Directorate.  You will contribute to the design development and testing of nuclear equipment and systems for Lawrence Livermore National Laboratory (LLNL) operations with fissionable materials.  You will also contribute to projects and task assigned to LLNL supporting the Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP).  This position is in the Nuclear Criticality Safety Division (NCSD).

This position will be filled at either level based on knowledge and related experience as assessed by the hiring team. Additional job responsibilities (outlined below) will be assigned if hired at the higher level.

This position requires full-time on-site presence due to the nature of the work.

You will 

• Perform criticality safety evaluations in conformance with DOE-STD-3007 and LLNL administrative procedures and participate in design and reviews of new or proposed changes to existing equipment or operating procedures.
• Perform walk-through inspections and basic annual reviews of operations and work authorization/work control documents and review safety procedures and documents for consistency with criticality safety evaluations and adequate implementation of criticality safety controls.
• Perform technical/scientific assignments of moderate to complex problems that require independent analysis and creativity and provide technical support to facility management engineers and scientists in scientific research and development projects and/or ongoing operations.
• Gather and analyze data and information in support of the work activity and deliver results in the form of documents calculations recommendations corrective actions or designs.
• Develop creative solutions to problems of moderate complexity contributing to the fulfillment of project and organizational goals.
• Frequent travel to the Nevada National Security Sites.
• Conduct Fundamentals of Criticality Safety training courses.
• Perform other duties as assigned.

Additional job responsibilities at the SES.3 level

• Prepare technical reports and present formal presentations to LLNL management and various internal and external audiences.
• Conduct formal on-the-job training informal presentations and consultations of criticality safety information to fissile material handlers designers and other clients.
• Interpret implement and provide guidance to internal customers on DOE regulations national consensus criticality safety standards and Laboratory policies related to criticality safety.

Qualifications :

• Ability to secure and maintain a U.S. DOE Q-level security clearance which requires U.S. citizenship.
• Bachelors Degree in Nuclear Engineering Physics or closely related scientific discipline or the equivalent combination of education and related experience.
• Comprehensive knowledge of and experience working in a nuclear facility nuclear reactor chemical high hazard (e.g. explosive) radiological operations or similarly complex or highly regulated facility.
• Broad application of technical analytical and decision-making skills and record of achievement in performing criticality safety evaluations or research.
• Proficient with personal computers and radiation transport software (e.g. COG MCNP SCALE).
• Experience preparing technical documents following appropriate protocols (e.g. criticality safety evaluations safety basis calculations design calculations and drawings/sketches).
• Working knowledge of DOE orders national consensus standards and engineering practices.
• Proficient verbal and written communication and interpersonal skills necessary to work effectively in a collaborative work environment.
• Ability to document present and/or explain technical or operational information and work results to management and stakeholders i.e. DOE DNFSB and other external agencies.

Additional qualifications at the SES.3 level

• Significant experience with nuclear and fissile material operations.
• Significant experience conducting safety evaluations in conformance with applicable DOE orders.

Qualifications We Desire

• Masters or Doctorate in Nuclear Engineering Physics or closely related discipline.
• Experience in criticality safety.
• Knowledge of LLNLs policies procedures and practices.

Pay Range

$132810.00  - $170556.00  Annually for the SES.2 level
$159330.00  - $204636.00  Annually for the SES.3 level

This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting.  An employees position within the salary range will be based on several factors including but not limited to specific competencies relevant education qualifications certifications experience skills seniority geographic location performance and business or organizational needs.

Additional Information :

#LI-Onsite

Position Information

This is a Career Indefinite position open to Lab employees and external candidates.

Why Lawrence Livermore National Laboratory

• Included in 2026 Best Places to Work by Glassdoor!
• Flexible Benefits Package
• 401(k)
• Relocation Assistance
• Education Reimbursement Program
• Flexible schedules (*depending on project needs)
• Our values - visit  Clearance

  This position requires a Department of Energy (DOE) Q-level clearance.  If you are selected we will initiate a Federal background investigation to determine if you meet eligibility requirements for access to classified information or matter. Also all L or Q cleared employees are subject to random drug testing.  Q-level clearance requires U.S. citizenship. 

  Pre-Employment Drug Test

  External applicant(s) selected for this position must pass a post-offer pre-employment drug test. This includes testing for use of marijuana as Federal Law applies to us as a Federal Contractor.

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  Remote Work :

  No

  
  

  Employment Type :

  Full-time