Associate Criticality Safety Engineer – Active Clearance Required

We have an opening for an Associate Criticality Safety Engineer within the Environment Safety and Health (ESH) 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 offers a hybrid schedule blending in-person and virtual presence. You will have the flexibility to work from home one or more days per week.

You will 

• Assist with criticality safety evaluations in conformance with DOE-STD-3007 and LLNL administrative procedures and support the review of new or proposed changes to existing equipment or operating procedures.
• Perform walk-through inspections and assist with basic annual reviews of operations and work authorization/work control documents and support the review of safety procedures and documents for consistency with criticality safety evaluations and adequate implementation of criticality safety controls.
• Perform technical/scientific assignments of limited complexity using established methods and procedures under general direction and provide technical support to engineers scientists and facility staff as a member of a team in scientific research and development projects and/or ongoing operations.
• Gather organize and assist in analyzing data and information in support of the work activities and help prepare documents calculations recommendations corrective action documentation designs or related technical work products.
• Contribute to solutions for routine or limited-complexity problems using standard techniques and established practices supporting project and organizational goals.
• Travel to the Nevada National Security Sites as needed.
• Conduct Fundamentals of Criticality Safety training courses.
• Perform other duties as assigned.

Qualifications :

• This position requires an active Department of Energy (DOE) Q-level clearance or active Top Secret clearance issued by another U.S. government agency at the time of hire.
•  Bachelors Degree in Nuclear Engineering Physics or closely related scientific discipline (e.g. mechanical/systems engineering nuclear physics particle physics radiochemistry) or equivalent combination of education and prior relevant experience.
• Fundamental knowledge of and some academic internship research or work experience in a nuclear facility nuclear reactor chemical high hazard radiological operation or similarly regulated technical environment.
• Ability to apply fundamental technical analytical and problem-solving skills to assigned work using established methods and procedures.
• Familiarity with personal computers and exposure to radiation transport software such as COG MCNP GEANT or SCALE is desirable.
• Experience modeling the Inherently Safe Subcritical Assembly (ISSA) and performing pulsed-neutron experiments.
• Experience performing reactor kinetics calculations and developing custom radiation transport code modules for specific experiments.
• Experience modeling critical and subcritical benchmark experiments in COG MCNP OpenMC.
• Ability to assist with preparing technical documents and calculations following established protocols and guidance.
• Basic familiarity with DOE orders national consensus standards and engineering practices is desirable.
• Proficient verbal and written communication and interpersonal skills to work effectively in a collaborative team environment.
• Ability to document and explain assigned technical or operational work results to supervisors project leads and team members.
• Ability to reprioritize and change programmatic direction depending on emergent requests and in collaboration with a variety of multidisciplinary teams.

Qualifications We Desire

• Masters Degree in Nuclear Engineering Physics or closely related scientific discipline or equivalent combination of education and prior relevant experience.
• Experience in criticality safety including preparing criticality safety evaluations and implementation of criticality safety controls.
• Knowledge of LLNLs policies procedures and practices.
• Knowledge of and/or experience with DOE STD-3007 and ANSI/ANS-8 Series Consensus Standards.

Pay Range: $121830 - $154500 Annually

This is the lowest to highest salary range in good faith 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-Hybrid

Position Information

This is a Flexible Term appointment which is for a definite period not to exceed six years.  If final candidate is a Career Indefinite employee Career Indefinite status may be maintained (should funding allow).

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 an active Department of Energy (DOE) Q-level clearance or active Top Secret clearance issued by another U.S. government agency at time of hire. 

  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 :

  Part-time