Senior Nuclear Engineer - TS/SCI Poly Required

The Leidos Analysis Solutions business area is seeking a Senior Nuclear Engineer to support critical national security missions in Reston, Virginia. In this role, you will apply advanced nuclear engineering principles in support of counterproliferation efforts and nuclear survivability (hardness) system design. Responsibilities include conducting technical assessments of foreign nuclear weapons infrastructure to reverse-engineer protective hardening measures and identify facility, process, and supply chain vulnerabilities. This unique role combines rigorous computational physics, engineering analysis, and all-source intelligence tradecraft to support the protection of national security infrastructure. The successful candidate will join a government-contractor team focused on the reverse engineering of above-ground and underground facilities, including their associated processes, systems, and equipment. You will develop innovative solutions through research, modeling, and application of industry best practices in a fast-paced, mission-driven environment within a government facility.

Counterproliferation & Defense Analytics Conduct high-fidelity technical reverse-engineering analyses and vulnerability assessments of domestic and foreign facilities, stockpiles, supply chains, and production processes. Support defense and intelligence partners by identifying vulnerabilities and informing strategic decision-making. Nuclear Hardness & Survivability Analyze the effects of nuclear weapons on facilities, infrastructure, equipment, and operational workflows. Develop protective design criteria using physics-based models addressing radiation effects, electromagnetic pulse (EMP), and related interference phenomena. Threat Modeling & Simulation Utilize advanced multiphysics modeling and simulation tools to evaluate structural, thermal, and electronic degradation of nuclear-related facilities and processes exposed to weapons effects. Perform computational analyses to assess system performance, resilience, and survivability. All-Source Intelligence Integration Monitor, query, and synthesize information from diverse intelligence and open-source datasets, including GEOINT, SIGINT, and OSINT. Assess foreign nuclear capabilities, technological developments, and projected timelines. Technical Reporting & Briefings Prepare detailed technical reports, engineering assessments, and executive-level briefings on foreign capabilities, vulnerabilities, and engineering validation methodologies. Communicate complex technical findings to government stakeholders and senior leadership. Subject Matter Expertise Serve as a recognized subject matter expert within the nuclear engineering and counterproliferation domain. Provide technical guidance across programs and support strategic initiatives. Required Education, Skills, and Experience Candidates for consideration must possess an in-scope and active TS/SCI Polygraph clearance and the ability/willingness to maintain this clearance while holding this position. U.S. Citizenship is required. ​ Bachelor's degree with 12+ years of relevant experience, or Master's degree with 10+ years of relevant experience. Demonstrated experience with nuclear weapons supply chains, manufacturing, fabrication, production, storage, or deployment processes and associated logistics. Experience assessing vulnerabilities across nuclear-related supply chains, stockpiles, and facilities, including development of mitigation strategies and countermeasures. Strong understanding of fault tree analysis, hazard analysis, and risk assessment methodologies. Deep technical knowledge of the nuclear fuel cycle, nuclear weapon design principles, radiation effects on materials, and electromagnetic shielding architectures. Experience developing and executing physics-based simulations using tools such as MCNP, SCALE, ORIGEN, COMSOL, and related modeling software, supplemented by data analysis tools such as Python,