Lead Reactor Physics & Shielding Engineer

Long Beach · On-site

About this role

Our Mission Is Simple: Democratize Access To Clean Energy

Welcome to BlueCore Energy! We are on a relentless mission to democratize access to clean energy. By designing and building advanced floating Pressurized Water Reactors (PWRs) on barges right here in Long Beach, CA, we are bringing scalable, clean, and reliable power to the world. Joining our team means getting in on the ground floor of a revolution in marine small modular reactors (SMRs). If you are passionate, driven, and ready to tackle some of the most exciting challenges of our time, we want you on our team!

Our Values

  • Humility — We hold strong opinions loosely, say "I don't know," ask for help early, and let the best idea win regardless of who it came from.

  • Inclusivity — The best engineering comes from many perspectives. We build a team where everyone is heard, and we mean it.

  • Pragmatism — We solve the real problem in front of us, reuse what already works, and value a tested answer over an elegant one.

About the Role

The Lead Reactor Physics & Shielding Engineer will own the neutronics doctrine and the radiological safety of our marine compact PWR. You will be responsible for defining the core geometry, reactivity control, and shutdown margins, while simultaneously owning the shielding analysis, radiological dose mapping, and source terms.


Responsibilities 

  • Provide comprehensive neutronics support, establishing core geometry, enrichment, lattice, beryllium reflector, and rotating-drum control architecture.

  • Own criticality, reactivity coefficients (MTC, Doppler), kinetics, depletion, and cycle length.

  • Establish and own the shutdown-margin and criticality-safety cases across the full fuel life cycle, including fresh, in-core, spent, and storage phases.

  • Maintain the criticality base deck and the SCALE calculation catalog.

  • Develop core and coolant source terms, and set the activation and decommissioning source term.

  • Design the primary and secondary shields, mapping both occupational and crew doses for a space-constrained vessel.

  • Analyze deep-penetration radiation streaming through structural penetrations utilizing variance reduction techniques. 

  • Supply critical neutronics inputs to Chapters 4, 5, and 15, and calculate control-room and offsite design-basis accident (DBA) doses.

Required Qualifications & Skills

  • MS or PhD in Nuclear Engineering, Reactor Physics, Health Physics, or radiation transport. 

  • Hands-on production depth in a continuous-energy Monte-Carlo transport and criticality code such as CASMO/SIMULATE, SCALE, MCNP, Serpent, or OpenMC.

  • Demonstrated radiation-transport shielding experience utilizing variance reduction tools like MAVRIC/Monaco, MCNP, or OpenMC.

  • Experience with a lattice-physics or depletion code such as CASMO, SCALE, or Serpent. 

  • Proficiency with a nuclide-inventory and decay tool such as ORIGEN or an equivalent software.

  • Deep understanding of NUREG-0800 Standard Review Plan (SRP) sections 4.2, 4.3, 9.1.1, 11.1, and 12.2–12.5. 

Desired Qualifications & Skills

  • Experience with marine compact PWR core physics, specifically drum-controlled or near-boron-free cores.

  • Ability to cross-verify codes and derive Upper Subcritical Limits (USL) via ICSBEP benchmarking per NUREG/CR-6698.

  • Familiarity with RG 1.183 (Alternative Source Term) and GDC 19 to ensure control-room Total Effective Dose Equivalent (TEDE) limits are met. 

  • Experience utilizing ENDF/B (VII.1 / VIII.0) data libraries in criticality and transport evaluations. 

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Working at BlueCore Energy

On-Site Requirement: Our team works together at our Long Beach facility, right next to our barge. 

 

Highly Cross-Functional: Startups move fast! You must possess the ability to seamlessly collaborate across multiple teams to rapidly solve problems and keep production moving.

 

Physical & Machinery Requirements: Because we are a hands-on startup, this role may require the ability to perform physical labor, navigate active construction/manufacturing zones, and/or operate heavy machinery and specialized manufacturing equipment as needed.

Company at a glance

Bluecore Energy is developing small modular, water-cooled nuclear reactors that operate aboard floating barges to deliver reliable, zero-emission power to ports, data centers, and critical infrastructure. Founded by Kofi Asante and headquartered at the Port of Long Beach, the company is the first small modular reactor company to establish headquarters inside a major U.S. port. Learn more at bluecore.energy.

Founded2026
Team Size11-50 employees
WorkspaceOn-site
IndustryNuclear Electric Power Generation
Location
Long Beach, California, United States

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