Senior Nuclear Radiation Shielding Engineer

The Senior Nuclear Radiation Shielding Engineer to support the design, analysis, and licensing of the SMR‐300, an integral pressurized water reactor small modular reactor.

The selected candidate will join an established and growing radiation protection and analysis team supporting SMR‐300 development activities, including radiation source term development, shielding design and optimization, dose assessment, and preparation of licensing documentation.

This role serves as a hands‐on technical contributor, supporting plant design optimization and regulatory compliance through defensible radiological analyses.

This role works independently performing detailed analyses, benchmark methods and models, clearly document results, and mentor junior engineers in analysis techniques and technical documentation.

Almondsbury (Bristol Area), UK – Relocation Assistance Available! Primary Responsibilities: Develop radiation source terms for normal operation, anticipated operational occurrences, and postulated accident conditions Perform radiation transport analyses to evaluate dose rates in plant systems, structures, and components Design and optimize radiation shielding to meet occupational exposure and site dose limits in accordance with ALARA principles Conduct radiological consequences and control room habitability analyses using accepted regulatory methodologies Perform reactor pressure vessel and structural component fluence evaluations to support shielding and material assessments Benchmark analytical models against experimental data and industry guidance to ensure technical defensibility Prepare technical reports and contribute to licensing documentation, including PSAR, FSAR, and responses to NRC Requests for Additional Information (RAIs) Participate in technical meetings with internal teams, partners, clients, and the U.S. Nuclear Regulatory Commission Mentor junior engineers and support the development of analysis standards and documentation best practices Requirements: Eligibility to work under U.S.

of Energy 10 CFR Part 810 export control regulations Bachelor’s degree in Nuclear Engineering, Physics, or a closely related field with 10+ years of relevant experience OR Master’s degree with 8+ years of relevant experience OR PhD with 6+ years of relevant experience Demonstrated experience in radiation shielding design, source term development, and radiological dose assessment Proficiency with radiation transport and dose analysis tools such as MCNP, SCALE, ADVANTG, GALE, ARCON96, RADTRAD, or equivalent codes Working knowledge of nuclear power plant operations and radiological protection programs Familiarity with NRC licensing processes and NUREG‐0800 Chapters 11 and 12 requirements Strong technical writing, documentation, and communication skills Programming or scripting experience (e.g., Python) to support analysis automation and data processing Experience supporting NRC audits, RAIs, and technical review meetings Experience integrating shielding design with plant layout and multidisciplinary engineering teams A Generation Ahead by DesignTM Investing in people who power the future. We believe great work deserves great rewards. Our benefits go beyond the basics, reflecting our commitment to supporting your whole self...your health, your future, and your career growth. This includes: Benefits: Private health insurance for physical and mental health, 24/7 GP access, dental/optical cashback and travel insurance for you and your family 25 days annual leave plus bank holidays, with Christmas shutdown Hybrid work opportunities available where business needs and role requirements allow Education assistance to support continued professional growth, reimbursement of professional membership fees Employer matched pension contributions, life insurance, enhanced maternity/paternity benefits If you’re driven to solve meaningful challenges and make a lasting impact, we invite you to build your career at Holtec— a generation ahead by designTM .