Criticality Safety Engineer – Nuclear Centrifuge Program

Company Overview

Napakiak Environmental and Construction (NEC) is a leading provider of information technology, technology development, and environmental and construction services, specializing in Federal and Commercial projects. Our company is committed to delivering high-quality solutions that meet stringent regulatory standards and client requirements.

We are seeking a Criticality Safety Engineer to support a long-term, first-of-a-kind nuclear centrifuge manufacturing and enrichment program at a critical transition point as the facility moves from design into testing, startup, and sustained production.

This role is part of an innovative private company funded by the U.S. Department of Energy, leading a national effort to reestablish domestic uranium enrichment capabilities long furnished by foreign countries—directly strengthening U.S. energy security and national defense.

This is a full-time, long-term position based in Oak Ridge, Tennessee, with primary responsibility for nuclear criticality safety analysis, controls, and authorization supportas the program matures from design intent to operations.

• Develop, implement, and maintain the criticality safety program for centrifuge manufacturing, testing, enrichment, and associated material handling operations
• Perform and document nuclear criticality safety analyses (NCSAs) in accordance with DOE Orders, 10 CFR 830, and applicable consensus standards (e.g., ANSI/ANS-8 series)
• Define, evaluate, and maintain criticality safety controls, limits, and requirements for fissile material processes, equipment, and facility layouts
• Support preparation and defense of Documented Safety Analysis (DSA) and Technical Safety Requirement (TSR) content related to criticality safety
• Support DOE nuclear authorizationactivities by providing technical justification for criticality safety assumptions, controls, and margins
• Lead or support Unreviewed Safety Question (USQ) Determinationsand change evaluations impacting fissile material form, mass, moderation, geometry, or operations
• Evaluate design changes, process modifications, and abnormal conditions to ensure continued compliance with criticality safety requirements
• Support startup, testing, and operational readiness reviews, ensuring criticality safety assumptions remain valid as the facility transitions into production
• Collaborate closely with engineering, manufacturing, operations, quality, and nuclear safety organizations to integrate criticality safety into facility and process design
• Interface with federal regulators and reviewers to explain criticality safety methodology, assumptions, and regulatory posture
• Support development of long-term criticality safety strategyas the program scales and evolves

• Bachelor’s degree in Nuclear Engineeringstrongly preferred; other engineering or physical science degrees considered with relevant criticality safety experience
• U.S. citizenship required
• Ability to obtain and maintain a government security clearance, as required
• Strong technical writing skills and ability to communicate complex safety analyses to regulators and stakeholders

Experience will be scoped based on candidate level:

• Experience supporting nuclear criticality safety analyses or safety basis documentation
• Familiarity with DOE nuclear safety requirements and ANSI/ANS criticality safety standards
• Experience supporting design reviews or process hazard evaluations involving fissile material

• Demonstrated experience authoring and maintaining NCSAs and criticality safety documentation
• Hands-on experience supporting USQs, safety basis updates, or operational authorization
• Experience supporting nuclear facility startup, testing, or operations involving enriched uranium

• Extensive experience leading criticality safety programs for complex nuclear facilities
• Deep understanding of DOE nuclear authorization processes and regulator expectations for criticality safety
• Proven ability to define criticality safety strategy, mentor engineers, and guide facilities through initial authorization and…