Safety Engineer Jobs in Massachusetts

Alva is seeking a Principal Safety Analysis Engineer to help build the thermal-hydraulic methods that underpin power uprate programs across the pressurized water reactor fleet. This is a methods development role at its core: you will develop, validate, challenge, and improve the analysis approaches used to determine safety margin, establish technical credibility, and support licensing decisions. The methods developed by this team will be foundational in determining the scale of uprate that can be achieved on each project and in driving those projects through licensing.

Why this role is different

• You will have meaningful ownership of a safety analysis capability being developed from the ground up, without being constrained by a legacy structure.
• See a direct connection between methods and plant impact. Your technical decisions will help determine where real thermal-hydraulic margin exists, what limits an uprate, and how much additional power can be credibly pursued.
• Help shape Alva at an early stage. The role offers genuine influence over the safety analysis program and the broader company, with the ability to move quickly, challenge assumptions, and introduce better ways of working.

Key Responsibilities

• Own methods development strategy for thermal-hydraulic safety analysis supporting PWR uprates, including evaluation-model approach, analysis scope, acceptance criteria, sensitivity strategy, uncertainty treatment, and interpretation of results.
• Assess Alva's analysis toolbox and help determine where existing methods are sufficient, where they require extension or validation, and where new methods or workflows should be developed.
• Develop, modify, review, and technically direct models using one or more nuclear safety analysis codes such as RELAP5, RETRAN, VIPRE, GOTHIC, TRACE, COBRA, SIMULATE, or equivalent tools.
• Lead verification, validation, calibration, and benchmarking of models and methods against plant data, test data, vendor information, prior analyses, and code-to-code comparisons; investigate discrepancies and identify the underlying physical or modeling cause.
• Develop defensible approaches to uncertainty, conservatism, scaling, stability, sensitivity, and margin assessment, with particular focus on distinguishing physical limitations from methodological limitations.
• Translate methods into repeatable, traceable engineering practice through calculation packages, methods documentation, technical bases, topical reports, licensing submittals, and responses to utility or NRC questions.
• Partner closely with licensing, fuel performance, systems engineering, plant integration, testing, and operations teams so that methods development remains connected to real plant decisions and project needs.
• Work directly with utility customers, vendors, and external partners to define data needs, communicate technical assumptions, and defend the analysis approach.
• Raise the capability of the broader team through technical review, mentoring, best-practice development, and selective improvement or automation of analysis workflows. What success looks like
• A technically credible, reusable methods basis for Alva's PWR uprate work, with clear understanding of model applicability, limitations, and validation pedigree.
• Feasibility studies that identify limiting phenomena, quantify meaningful thermal-hydraulic margin, and distinguish where better methods can recover otherwise hidden conservatism.
• Analyses that are traceable, validated, explainable, and suitable for customer and regulatory use.
• A stronger internal safety analysis capability in which junior engineers can execute high-quality work against clear methods, standards, and technical expectations.
• A long-term methods roadmap that supports Alva as the number and complexity of uprate projects grow.

Qualifications

• 10+ years of nuclear thermal-hydraulic safety analysis or methods-development experience, preferably involving commercial PWRs, reactor vendors, national laboratories, technology developers, utilities, or specialized nuclear consulting environments.
• Deep hands-on experience with one or more nuclear systems, subchannel, or safety-analysis codes such as RELAP5, RETRAN, VIPRE, GOTHIC, TRACE, COBRA, SIMULATE, or equivalent tools.
• Demonstrated experience developing, modifying, validating, benchmarking, or qualifying thermal-hydraulic models or analysis methods.
• Strong command of thermodynamics, heat transfer, fluid dynamics, two-phase flow, and transient analysis, with the ability to explain the physical basis behind model behavior and challenge results that do not make sense.
• Experience with one or more of the following: evaluation-model development, code-to-code benchmarking, test-data validation, uncertainty methodologies, scaling analysis, stability analysis, sensitivity analysis, or margin methodology.
• Ability to translate technical methods into defensible engineering documentation and communicate the basis of an analysis to peers, customers, licensing teams, and regulators.
• Experience reviewing the work of others, identifying hidden modeling risk, setting technical direction, and mentoring engineers in analysis methods and fundamentals.
• Programming or scripting capability for analysis workflows, automation, and data reduction (for example Python, MATLAB, FORTRAN, C++, or similar).
• Bachelor's degree in Nuclear, Mechanical, Chemical Engineering, or a related technical field; advanced degree preferred. Preferred experience

• Commercial PWR safety analysis, including Chapter 15 or equivalent accident and transient analysis. • Power uprates, steam generator replacement programs, or plant modifications requiring re-analysis of safety margins.

• Authorship or review of topical reports, safety analysis reports, licensing submittals, or formal responses to NRC or utility technical questions.

Who We Are

Alva Energy is transforming how nuclear power scales. Our standardized power uprate approach helps assisting commercial nuclear reactors generate and deliver 10 gigawatts of new nuclear capacity to the U.S. grid through expert project delivery and systemic approach that brings predictability and speed to an industry that needs both.

We're an equal opportunity employer, committed to hiring and evaluating people on their work, not their race, color, religion, sex, sexual orientation, gender identity or expression, national origin, age, disability, veteran status, or any other characteristic that has nothing to do with how well they can do the job.

We're also committed to making our hiring process accessible to everyone. If you need accommodation at any point: applying, interviewing, or otherwise, reach out to your recruiter, who can help arrange it.