HR Generalist

The Nuclear Company is the fastest growing AI tech-enabled startup in the nuclear and energy space, pioneering a fleet-scale approach to building the next generation of nuclear reactors. Through our design-once, build-many model, we're accelerating the deployment of safe, reliable, and affordable nuclear energy.
We operate with an AI-first mindset. Every employee is expected to leverage AI, technology, and the Nuclear Operating System (NOS) as integral components of their role to improve the quality, speed, and impact of their work. We expect every team member to continuously identify opportunities to automate workflows, enhance decision-making, improve processes, and contribute to the ongoing evolution of NOS as a strategic operating capability that enables The Nuclear Company to scale with excellence.
We hire people who are driven by purpose, thrive in ambiguity, and are energized by building what has never been built before. Our team combines intellectual curiosity with high agency, embraces candid feedback and continuous learning, and holds themselves and others to exceptional standards. Our values—Transparency, Responsibility, Unity, Scrappiness, and Tenacity—guide how we hire, collaborate, and make decisions every day. They are not words on a wall; they are the standard by which we operate. TRUST is the foundation of our safety culture, fostering intellectual honesty, accountability, and open communication, while our values challenge every team member to execute with urgency, humility, resilience, and an unwavering commitment to our mission.
About the role
The HR Generalist is the operational backbone of our HR team, delivering hands-on HR support across the entire employee lifecycle for the organization. This role executes the day-to-day programs and transactions that keep the employee experience running smoothly: onboarding and offboarding, leave of absence administration, employee data and systems accuracy, background checks, contractor management and relocation coordination, and early career program logistics. You'll also be the go-to resource for general HR questions from our Field Services team including the temporary field workforce. You will work closely with both the VP, HR and the Director, HR & HR Technology, giving you visibility across a broad, technically complex organization while building deep expertise in HR operations. This team does not handle talent acquisition or recruiting — that is owned by a separate Talent team.
Responsibilities
Leave management
Administer all employee leaves of absence (FMLA, state/local, personal, military, parental) and coordinate short- and long-term disability claims with our carrier (Lincoln), from intake through return to work.
Manage ADA accommodation requests and track leave eligibility and case status in UKG, keeping employees, managers, and case files accurate, compliant, and up to date.
Onboarding & offboarding
Own new hire onboarding end-to-end — orientation, paperwork, and background check verification (Checkr) — for a smooth start for every new hire.
Lead offboarding, including exit interviews and timely, accurate termination processing in UKG.
HR operations & systems
Serve as day-to-day UKG super-user for employee data changes, leave tracking, and terminations, partnering with the Director, HR & HR Technology on process and system design.
Support HR compliance work, including maintenance of the employee handbook and policies, alongside the VP, HR.
Employee relations & talent program support
Provide first-line employee relations support, documenting concerns and triaging issues to the appropriate HRBP .
Support execution of enterprise talent programs (performance management, merit planning, succession/talent reviews) and coordinate early career/internship program logistics.
Serve as the first point of contact for general HR questions from the Field Services team and our temporary/contract field workforce — policies, pay, and benefits basics — escalating as needed.
Contractor management & relocation