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.

Location:
Madrid, SpainPrimary

Responsibilities:
Develop radiation source terms for normal operation, anticipated operational occurrences, and postulated accident conditionsPerform radiation transport analyses to evaluate dose rates in plant systems, structures, and componentsDesign and optimize radiation shielding to meet occupational exposure and site dose limits in accordance with ALARA principlesConduct radiological consequences and control room habitability analyses using accepted regulatory methodologiesPerform reactor pressure vessel and structural component fluence evaluations to support shielding and material assessmentsBenchmark analytical models against experimental data and industry guidance to ensure technical defensibilityPrepare 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 CommissionMentor junior engineers and support the development of analysis standards and documentation best practicesRequirements:Eligibility to work under U.
S. Department of Energy 10 CFR Part 810 export control regulationsBachelor’s degree in Nuclear Engineering, Physics, or a closely related field with 10+ years of relevant experienceOR Master’s degree with 8+ years of relevant experienceOR PhD with 6+ years of relevant experienceDemonstrated experience in radiation shielding design, source term development, and radiological dose assessmentProficiency with radiation transport and dose analysis tools such as MCNP, SCALE, ADVANTG, GALE, ARCON96, RADTRAD, or equivalent codesWorking knowledge of nuclear power plant operations and radiological protection programsFamiliarity with NRC licensing processes and NUREG-0800 Chapters 11 and 12 requirementsStrong technical writing, documentation, and communication skillsProgramming or scripting experience (e.g., Python) to support analysis automation and data processingExperience supporting NRC audits, RAIs, and technical review meetingsExperience integrating shielding design with plant layout and multidisciplinary engineering teamsA Generation Ahead by Design™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.
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 design™.

📌 Senior Nuclear Radiation Shielding Engineer (Comunidad de Madrid)
🏢 Holtec
📍 Comunidad de Madrid