Senior TH Safety Analysis Engineer

Deep Fission is a nuclear technology company pioneering the development of a revolutionary deep borehole pressurized water reactor. The company is seeking an experienced Senior Engineer to support performance of thermal-hydraulic and nuclear safety analyses for the design and licensing of its innovative reactor.

Responsibilities:

• Perform design-basis and beyond-design-basis thermal-hydraulic analyses, including non-LOCA transients, reactivity-initiated accidents (RIAs), loss-of-flow, and station blackout (SBO) scenarios
• Develop, maintain, and benchmark reactor system models using T/H codes in accordance with applicable regulatory requirements and quality assurance standards
• Support the development and execution of the Code Validation and Verification (V&V) program, including the preparation of V&V reports and uncertainty quantification in support of NRC licensing submittals
• Contribute to the development of Deep Fission’s overall safety analysis methodology and licensing strategy, including selection of analysis codes, determination of licensing basis events, and definition of acceptance criteria
• Prepare and review safety analysis documentation including design-basis accident analyses, safety analysis reports (PSDA/DSA or PSAR/FSAR sections), technical specifications bases, and responses to regulator questions and requests for information
• Ensure effective coordination with reactor physics, systems, mechanical, and licensing teams to maintain technical alignment across the design and safety basis
• Participate in design reviews, safety review committee activities, and in-person technical workshops
• Promote a proactive nuclear safety culture and advocate for Deep Fission and its technology in technical and regulatory forums
• Perform additional tasks as requested by management, which may include supporting construction, procurement, startup testing, and operational licensing activities as the project matures

Requirements:

• 7+ years of experience performing nuclear thermal-hydraulic and safety analyses in a licensed nuclear application environment
• Bachelor's degree in Nuclear Engineering, Mechanical Engineering, or a closely related technical field
• Demonstrated proficiency in one or more NRC-accepted T/H system codes applied in licensed PWR applications, including RETRAN, RELAP5 (or RELAP5-3D), TRACE, and/or GOTHIC
• Experience developing and executing reactor system models for design-basis LOCA and non-LOCA analyses, including model development, nodalization, and steady-state benchmarking
• Working knowledge of NRC regulatory requirements applicable to safety analysis, including 10 CFR Part 50, Appendix K, the Revised Acceptance Criteria (Best-Estimate LOCA), and associated regulatory guides
• Familiarity with nuclear quality assurance requirements (e.g., 10 CFR 50 Appendix B, NQA-1) and their application to safety analysis and software V&V
• Proven ability to prepare and review technical documentation intended for NRC review, including safety analysis calculations, topical reports, or FSAR sections
• Ability to work effectively in a virtual and hybrid team environment with multiple interfaces and stakeholders
• Must be a U.S. person eligible to meet DOE Export Control requirements under 10 CFR 810
• Master's degree or Ph.D. in Nuclear Engineering or Mechanical Engineering
• Licensed Professional Engineer (PE) in a relevant discipline
• Direct experience supporting NRC licensing submittals, including topical report preparation, RAI responses, and/or ACRS interactions
• Experience developing or contributing to a safety analysis methodology program at a reactor vendor, utility, or nuclear engineering firm
• Familiarity with uncertainty quantification methods (e.g., CSAU, ASTRUM, or similar statistical approaches) for best-estimate T/H analyses
• Experience with first-of-a-kind nuclear designs, SMRs, or novel licensing pathways (10 CFR Part 52 or emerging 10 CFR Part 53 framework)
• Proficiency with scripting tools (Python, MATLAB) for model automation, post-processing, and sensitivity studies
• Experience with AI-enabled engineering platforms and modern simulation toolchains