Principal/Lead Nuclear Engineer

MPR Associates; Alexandria (VA); On-site; USD 120,000 - 150,000; Full time

Job summary

A leading nuclear engineering firm in Alexandria, VA is seeking a Principal/Lead Nuclear Engineer. This role involves providing subject matter expertise across advanced reactor technologies and mentoring next-generation engineers. Candidates should have over 15 years of experience in nuclear engineering, strong communication skills, and familiarity with NRC regulations. The position offers competitive compensation and the opportunity to work on diverse, cutting-edge projects. Frequent collaboration with clients and stakeholders is expected, alongside some travel requirements.

Qualifications

• 15+ years of nuclear engineering experience across multiple technical areas.
• Proficiency in nuclear engineering software and familiarity with reactor designs.
• Strong understanding of NRC regulations and analytical skills.

Responsibilities

• Serve as a subject matter expert across various nuclear engineering projects.
• Develop design solutions for complex technical challenges in reactor technologies.
• Coach and mentor junior engineers and lead by example.

Skills

Nuclear engineering experience

Communication skills

Analytical skills

Mentorship

Business development

Education

Bachelor's degree in Nuclear or Mechanical Engineering

Advanced degree (MS or PhD)

Tools

MCNP

SCALE

ORIGEN

RELAP

Job description

Principal/Lead Nuclear Engineer

Overview

As a Principal/Lead Nuclear Engineer at MPR, you'll work across advanced fission reactors, operating nuclear plants, and research facilities - bringing your expertise to a diverse range of technologies and reactor concepts. Consulting means no two projects are the same: different clients, different challenges, different problems to solve. It's the kind of breadth that keeps the work engaging and your skills continuously growing.

Your role will primarily focus on providing subject matter expertise and mentorship to the next generation of nuclear engineering experts and leveraging your experience and connections to capture cutting edge project for MPR. Specifically, your expertise will be invaluable to achieve:

• Serving as a subject matter expert on a wide array of nuclear engineering projects
• Help expand MPR's network within the nuclear industry, and
• Provide mentorship and guidance to the next generation of nuclear engineers.

Because of MPR's role as trusted partner for virtually all cutting edge advanced nuclear suppliers, project workload will vary significantly over time. Some examples of the types of projects you could support include:

• Independent evaluation of advanced reactor designs (molten salt, sodium‑cooled fast reactors, high‑temperature gas reactors, microreactors)
• Fusion device thermal and radiological design
• Operating nuclear plant engineering support and analysis (PWR, BWR fleet)
• Research and test facility design and safety analysis
• Loss of coolant accident analysis and source‑term evaluation across reactor types
• Novel fuel form and component qualification for multiple technologies
• Criticality safety evaluations for DOE facilities
• Independent, technology comparison studies for utilities and investors

The role requires deep expertise in or an ability to quickly master several nuclear engineering related topics, including neutronics, thermal hydraulics, shielding, fuel and nuclear materials, and radiological consequence evaluation combined with strong communication skills, adherence to best practices, and an eye for growing MPR's portfolio.

Duties/Responsibilities

Typical duties for the role will vary based on project and workload at MPR, but will likely include an array of the following:

Technical Expertise

• Develop design/analytical solutions for complex technical challenges across diverse reactor technologies and
• Oversee MPR engineers performing neutronics simulations and core design: criticality safety evaluations, critical core configurations, fuel cycle management, activation calculations, radiation detection and shielding analyses: alarm setpoint determination, shielding optimization, ALARA implementation, dosimetry calculations
• Review and validate work performed by other MPR engineers
• Challenge vendor assumptions and verify results using first principles thinking

Business Development

• Identify and pursue opportunities to grow MPR’s project portfolio with existing and new clients
• Take a lead role in client and stakeholder interactions by effectively communicating technical results

Mentorship

• Coach and mentor engineers through execution of complex nuclear analysis work spanning different technical domains and lead by example
• Work with MPR leadership to identify pathways for junior engineers to grow

Qualifications

Competitive candidates will have most of the following:

Education

• Bachelor’s degree in Nuclear Engineering or Mechanical Engineering with nuclear concentration
• Advanced degree (MS or PhD) is a plus but not required

Technical Experience

• 15+ years of nuclear engineering experience with demonstrated expertise across multiple technical areas (neutronics, thermal‑hydraulics, radiation detection, shielding, radiological consequence evaluation)
• Proficiency with common nuclear engineering software: MCNP, SCALE, ORIGEN, RELAP, or equivalent tools
• Familiarity with both light water and non‑light water reactor designs, or fusion device thermal and radiological designs
• Experience developing test plans for novel nuclear designs (new fuel forms, components, etc.)
• Strong understanding of NRC regulations and guidance for reactor analysis (e.g., loss of coolant accident analysis methods, source‑term, licensing basis)
• Strong analytical skills grounded in first principles—not just software proficiency or vendor‑specific methodologies
• Ability to work across engineering disciplines to evaluate all facets of technical problems
• Deep understanding of nuclear physics, thermal‑hydraulics, materials behavior, and radiological phenomena

Leadership & Communication Skills

• Excellent verbal and written communication skills—you can explain complex nuclear phenomena to clients, regulators, and non‑specialists
• Experience presenting at industry conferences and engaging with external audiences
• Proven ability to oversee and mentor less experienced engineers and building teams
• Ability to manage multiple concurrent projects across different reactor technologies and teams
• Demonstrated success building and maintaining client relationships
• Experience identifying and pursuing new business opportunities
• Motivated to tackle unfamiliar problems and take on new responsibilities
• Persistent, questioning attitude—and the ability to accept that in others
• Strong time management and organizational skills
• Receptive to constructive feedback and continuous improvement

Preferred Experience

• Similar lead/subject matter expertise from previous job experience
• Direct experience with NRC licensing processes and regulatory interactions
• Published technical work or conference presentations
• Track record of successful business development in the nuclear industry
• Experience evaluating multiple competing reactor technologies

Required

• This position must meet Export Control compliance requirements, therefore a “US Person” as defined by 22 C.F.R. * 120.15 is required. “US Person” includes US Citizen, lawful permanent resident, refugee, or asylee.

Locations: Alexandria VA (HQ), East Lyme CT, Burlington MA, or Salt Lake City UT

Position Type: Full‑time, exempt

Travel: 10‑20% as required by project assignments, including client sites, test facilities, regulatory meetings, and visits between MPR offices

Work Environment: Collaborative and technically rigorous—you’ll lead multiple concurrent projects across different reactor technologies, mentor engineers across technical domains, and continuously expand your expertise while maintaining independence from vendor‑specific approaches

MPR Associates, Inc. is an equal opportunity and affirmative action employer, who participates in E‑Verify. All qualified applicants will receive consideration for employment without regard to race, color, national origin, sex, religion, age, disability, veteran’s status, sexual orientation, gender identity, genetic information or any other classification as required by applicable laws. MPR is a certified Virginia Values Veterans (V3) employer.