Principal Civil Engineer - TS/SCI Polygraph Required

Leidos; Reston (VA); On-site; USD 139,000 - 251,000; Full time

Job summary

Leidos in Reston, Virginia seeks a Principal Civil Engineer to support national security missions. The role focuses on assessment, reverse engineering, and characterization of complex facilities in denied-access environments, reconstructing layouts and supporting infrastructure for CBRN processes.

The successful candidate will lead engineering analyses, collaborate with government and contractor teams, and deliver authoritative technical assessments in fast-paced government facilities.

Qualifications

• Active TS/SCI clearance with the ability to maintain it.
• U.S. Citizenship required.
• Master's degree with 15+ years of relevant experience.
• Experience in facility analysis and infrastructure vulnerability assessments.
• MEP systems knowledge for complex facilities.

Responsibilities

• Reverse engineer complex industrial processes and facility layouts to assess mission relevance.
• Evaluate underground and hardened facilities for structural survivability.
• Create 3D models and simulate facility configurations.
• Identify vulnerabilities and potential threat vectors.
• Prepare technical reports and brief senior stakeholders.
• Lead cross‑disciplinary teams and provide SME guidance.

Skills

TS/SCI clearance

Senior engineering experience

3D modeling & CAD

MEP systems knowledge

Education

Master's degree +15+ years of relevant experience

Doctorate +13+ years of relevant experience

Tools

Autodesk Revit

BIM platforms

Job description

Leidos is seeking an accomplished Principal Civil Engineer to support high-priority national security missions in Reston, Virginia. This role focuses on the assessment, reverse engineering, and characterisation of complex above-ground and subterranean facilities located in denied-access environments. The successful candidate will leverage extensive engineering expertise to reconstruct facility layouts, operational workflows, and supporting infrastructure associated with chemical, biological, radiological, and nuclear (CBRN) industrial processes. Through detailed analysis of facility design, operations, and infrastructure, you will identify vulnerabilities, assess potential threat vectors, and provide critical engineering insights that support mission planning and decision-making.

This position requires a highly experienced engineer who can develop sound technical assessments in environments where complete information is rarely available. The ideal candidate combines creativity, engineering rigor, and exceptional analytical skills with a meticulous attention to detail. As a senior technical leader, you will collaborate with interdisciplinary teams of government and contractor professionals while serving as a trusted subject matter expert in support of complex intelligence and defense missions. Work is performed in a fast-paced, mission-focused environment within a government facility.

Primary Responsibilities

• Reverse Engineering & Characterization
  Analyze and characterize complex industrial processes, equipment configurations, and facility designs to determine functional attributes, operational capabilities, and mission relevance.
• Subterranean & Hardened Facility Analysis
  Evaluate the structural design, geological overburden, and survivability of underground facilities (UGFs) and deeply buried hardened structures.
• 3D Modeling & Simulation
  Utilise advanced CAD and engineering simulation tools to develop accurate 3D models of facilities, underground structures, floor plans, utility systems, and supporting infrastructure.
• Vulnerability & Resilience Assessments
  Conduct detailed structural and functional analyses to identify systemic weaknesses, single points of failure, and assess the resilience of critical infrastructure against a range of threat vectors.
• Workflow & Infrastructure Analysis
  Evaluate facility support systems and operational workflows, including specialised HVAC systems, power distribution networks, utility infrastructure, and structural integrity considerations.
• Technical Reporting & Briefing
  Develop comprehensive engineering assessments, reports, and technical products in accordance with Intelligence Community standards. Present findings, technical analyses, and recommendations to senior government and Department of Defense stakeholders.
• Subject Matter Expertise & Technical Leadership
  Serve as a recognised subject matter expert within your technical domain, providing authoritative engineering guidance and supporting multidisciplinary teams addressing complex mission challenges.

Required Basic Qualifications

• 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.
• Demonstrated expertise in engineering principles, theories, concepts, and their application across a broad range of highly complex programs and mission requirements.
• Master's degree with 15+ years of relevant experience, or a Doctorate with 13+ years of relevant experience.
• Relevant experience includes facility analysis, infrastructure vulnerability assessments, and structural engineering within commercial, Department of Defense, or Intelligence Community environments.
• Industrial & Facility Focus: Proven experience analysing chemical, nuclear, or biological industrial processes and their associated facility footprints, including both above-ground facilities and subterranean environments.
• MEP Systems Knowledge: Strong multidisciplinary understanding of Mechanical, Electrical, and Plumbing (MEP) system design, integration, and operational functionality within complex industrial or military facilities, including specialised containment, filtration, and backup power systems.

Preferred Qualifications

• Weapons Effects & Survivability: Experience or training in blast mitigation, weapons effects, or structural hardening principles.
• Geotechnical Engineering: Knowledge of rock mechanics, tunneling engineering, or geomechanics as applied to the analysis of deeply buried underground facilities (UGFs).
• BIM Expertise: Experience with Autodesk Revit or other Building Information Modelling (BIM) platforms for multidisciplinary coordination, MEP integration, and advanced facility visualisation.
• Advanced Simulation: Experience utilising BIM data to support engineering simulations, blast effects analysis, or vulnerability assessment workflows.
• Infrastructure Modeling: Experience with VENTSIM, ETAP, or similar infrastructure modelling and simulation software.
• All-Source Information Evaluation: Demonstrated experience researching, assessing, and synthesising diverse intelligence and technical sources, including classified intelligence, open-source information, and grey literature such as foreign technical journals, patents, and equipment catalogues, to support facility and infrastructure characterisation.
• Professional Engineer (PE) certification.
• Military or defence-related experience.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo - because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 - and moving faster than anyone else dares.

Original Posting

August 14, 2026
For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range

Pay Range $139,100.00 - $251,450.00

About Leidos

Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $16.7 billion for the fiscal year ended January 3, 2025. For more information, visit www.Leidos.com.

Pay And Benefits

Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available at www.leidos.com/careers/pay-benefits.

Securing Your Data

Beware of fake employment opportunities using Leidos' name. Leidos will never ask you to provide payment-related information during any part of the employment application process (i.e., ask you for money), nor will Leidos ever advance money as part of the hiring process (i.e., send you a check or money order before doing any work). Further, Leidos will only communicate with you through emails that are generated by the Leidos.com automated system – never from free commercial services (e.g., Gmail, Yahoo, Hotmail) or via WhatsApp, Telegram, etc. If you received an email purporting to be from Leidos that asks for payment-related information or any other personal information (e.g., about you or your previous employer), and you are concerned about its legitimacy, please make us aware immediately by emailing us at [e-mail]. If you believe you are the victim of a scam, contact your local law enforcement and report the incident to the U.S. Federal Trade Commission.

Commitment to Non-Discrimination

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.