Safeguards & Non-Proliferation Engineer Location: Bellevue, WA (Onsite Preferred) Employment Type: Contract Duration: 12 months Travel: 10–20% System One is seeking a Safeguards & Non-Proliferation Engineer to support a cutting-edge fast-spectrum, chloride salt-cooled molten salt reactor project. This role focuses on developing material accounting methodologies for an advanced reactor design with continuously flowing fuel, where traditional safeguards and inventory methods are not applicable. This is a unique opportunity to contribute to the future of nuclear energy by supporting the design and implementation of modern safeguards strategies using advanced computational tools, process monitoring, and uncertainty quantification techniques. Key Responsibilities: + Develop methodologies and tools for calculating special nuclear material (SNM) inventories and associated uncertainties in molten salt fuel and waste products. + Create and apply statistical methods for detecting inventory losses or anomalies. + Quantify and propagate uncertainty from a range of operational and data sources. + Perform sensitivity analyses to identify key sources of uncertainty and guide instrumentation and safeguards development. + Work cross-functionally with engineers and scientists to support material accounting and non-proliferation solutions across reactor systems. + Assist in licensing-related activities with domestic and international regulatory bodies. + Participate in training programs and workshops related to safeguards and non-proliferation. + Present findings through technical reports, publications, and professional presentations. Required Qualifications: + B.S. with 4–6 years, M.S. with 2–3 years, or Ph.D. with 1–2 years of relevant experience in mathematics, engineering, data science, or a related technical discipline. + Strong knowledge of numerical methods related to nuclear systems, such as isotopic depletion, particle transport, or kinetics. + Demonstrated experience in uncertainty analysis and quantification for complex systems. + Proficiency with nuclear engineering software such as MCNP, SCALE, Serpent, or similar. + Programming proficiency in at least one language (Python, C++, etc.), with preference for Git/GitHub workflows. + Strong problem-solving, analytical, and communication skills. + Ability to operate in a fast-paced, iterative development environment. + Strong collaboration and organizational abilities. Preferred Qualifications: + Familiarity with safeguards approaches and material control/accounting (MC&A) for advanced reactors or fuel cycle facilities. + Experience in molten salt or advanced reactor design. + Knowledge of regulatory frameworks and quality assurance programs (e.g., NQA-1). + Prior experience working with domestic or international nuclear regulatory or oversight agencies. System One, and its subsidiaries including Joulé, ALTA IT Services, and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan. System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law. Ref: #161-Managed Staffing Charlotte System One, and its subsidiaries including Joulé, ALTA IT Services, CM Access, TPGS, and MOUNTAIN, LTD., are leaders in delivering workforce solutions and integrated services across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible full-time employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan. System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law.