Mechanical Engineer

Mid-Senior Level | Full-time
Business Operations | Livermore, CA | 08/06/2026
Reference #: REF
8674N
Job Code: TSS.
3 Technical Services & Ops MTS 3 / TSS.
4 Technical Services & Ops MTS 4
Organization: Project Management Office
Position Type: Career Indefinite
Security Clearance: Anticipated DOE Q clearance (requires U.S. citizenship and a federal background investigation)
Drug Test: Required for external applicant(s) selected for this position (includes testing for use of marijuana)
Medical Exam: Not applicable Apply Now

Join us and make YOUR mark on the World!

Lawrence Livermore National Laboratory (LLNL) has turned bold ideas into world-changing impact advancing science and technology to strengthen U.S. security and promote global stability.

Our mission spans four critical national security areas nuclear deterrence, threat preparedness, energy security, and multi-domain defense empowering teams to take on the toughest challenges of today and tomorrow. With a culture built on innovation and operational excellence, LLNL is a place where your expertise can make a real impact.

We have an opening for a Mechanical Engineer. You will provide engineering design solutions for the Laboratory’s mechanical infrastructure, building HVAC systems, building automation and DDC control systems, energy management, laboratory design, and central plant-type equipment in support of projects associated with new construction, remodeling, and modifications to conventional office and laboratory facilities. This position is in the Project Management Office (PMO).

The Project Management Office (PMO) provides LLNL with engineering, design, estimating, construction, and project management services. PMO provides infrastructure services to enable cutting-edge research and development in the areas of defense technologies, global security, laser science, bioscience, and more. PMO offers cradle to grave infrastructure services to achieve reliable delivery of completed projects with priority on safety, collaboration, and a workforce working toward our shared vision.

This position may offer a hybrid schedule, which includes the flexibility to work from home one or moredays per week, after a probationary period. The specifics of the hybrid schedule, including the exact number of days required in the office and virtual work options may vary based on the needs of the team and the organization.

This position will be filled at either level based on knowledge and related experience as assessed by the hiring team. Additional job responsibilities (outlined below) will be assigned if hired at the higher level.

You will

• Perform independent technical tasks associated with the engineering, planning, design, and construction of projects associated with LLNL’s mechanical infrastructure.
• Perform computer-based analyses of heating and cooling load calculations, energy management, and life-cycle cost.
• Prepare mechanical construction documents, including scoping criteria, construction drawings, specifications, procurement specifications, duct and pipe sizing, HVAC load calculations, and AutoCAD drawings.
• Provide engineering support during construction by reviewing submittals and shop drawings, responding to contractor questions, evaluating change-order requests, resolving field issues, observing construction activities, and performing inspections. Provide engineering analysis and solutions to a diverse range of moderately complex site building mechanical systems issues and/or problems.
• Develop approaches to solve moderately complex technical issues associated with specific projects using independent judgment and analysis.
• Represent the organization in providing engineering solutions to a diverse range of moderate to complex facility mechanical technical issues and/or problems associated with specific projects.
• Provide engineering support during construction by reviewing submittals and shop drawings, responding to contractor questions, evaluating change order requests, resolving field problems, and performing inspections.
• Lead assigned internal mechanical projects and serve as the mechanical lead for in-house design projects, with responsibility for…