Nuclear Facility Mechanical Project Engineer

Associate | Full-time Engineering | Livermore, CA | 09/29/2026Reference #: REF8928QJob Code: SES.2 Science & Engineering MTS 2 / SES.3 Science & Engineering MTS 3Organization: EngineeringPosition Type: Career IndefiniteSecurity 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: A job-related pre-placement medical examination may be required Company DescriptionJoin 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.Job DescriptionWe are seeking a Nuclear Facility Mechanical Project Engineer to provide engineering design solutions for new construction, upgrades to facility mechanical systems (i.e., ventilation, fire suppression, compressed gas, chillers, boilers), and modifications to conventional office and laboratory facilities. You will apply technical knowledge in mechanical engineering to develop conceptual ideas into workable and cost-effective solutions that maintain facilities supporting research and investigations of nuclear materials. You will participate in new and ongoing projects with technical responsibilities including design, development, fabrication, integration, testing and fielding of facility projects and upgrades. This position will report programmatically to the Facility Projects Capabilities Manager in the Superblock. This position is in the Defense Technologies Engineering Division (DTED) within the Engineering Directorate.This position requires full-time on-site presence due to the nature of the work.This position will be filled at either the SES.2 or SES.3 level depending on your qualifications. Additional job responsibilities (outlined below) will be assigned if you are selected at the higher level.You will Independently prepare and influence moderately complex mechanical designs that require in-depth analysis, ingenuity, and creativity by utilizing design criteria, calculations, schematics, sketches, construction documents, procedures, and specifications.Utilize technical engineering skills and moderately complex mechanical system experience to develop detailed designs, drawings, calculations, bills of materials, budgets, presentations, schedules, and work planning documentation to support facility improvement projects and activities, including evaluating system capacities, planning sequencing of work, and ensuring constructability.Support significant R&D projects by applying comprehensive knowledge, skills, and innovation to create mechanical solutions that are safe and compliant with DOE orders and specifications and LLNL procedures and work control system processes.Determine functional requirements for mechanical systems in a hazard category 2 nuclear facility for new or modified specialized equipment and support systems and perform advanced engineering calculations.Write and communicate clear concise requirements using in-depth analysis and/or ingenuity.Participate in design reviews to obtain approvals of project scope and designs.Provide technical input to others on moderately complex design requirements and identify and evaluate potential system impacts for projects affecting facility systems while complying with LLNL procedures, work control system processes, and DOE requirements.Guide the successful completion of projects, provide regular status updates to stakeholders, and recognize when to develop and initiate workarounds to project obstacles.Provide engineering support during construction performed by outside contractors including reviewing submittals and shop drawings, responding to contractor questions, evaluating change order requests, or resolving field problems.Generate detailed plans, schedules, and budgets for project activities.Perform other duties as assigned.Additional job responsibilities, at the SES.3 level Lead highly complex internal multi-disciplinary engineering projects as the Project Lead or Design Manager with overall responsibility for developing technical criteria, budgets, schedules, and deliverables.Develop, implement, and provide highly advanced engineering solutions and technical analysis to resolve highly complex technical issues.Provide project planning and project management knowledge and skills for significant R&D projects, while also applying high level expertise and innovation to create mechanical solutions that are safe and compliant with DOE orders and specifications.Lead complex internal system projects with responsibility for the development of and compliance with technical criteria, schedules, and deliverables, and direct the work of design drafters preparing drawings.Collaborate with senior stakeholders, management, and DOE personnel in management and execution of the portfolio of facility projects, serving as the primary technical resource, and influencing and providing strategic technical advice.Participate in the planning development, implementation, and refinement of broad project vision and strategy and influence technical direction for the projects and the team to drive successful outcomes for deliverables.Contribute to new ideas, modify approaches, and/or redefine customer requirements that impact organizational operations or directions.Provide advanced level capability in the design and analysis of highly complex mechanical systems.QualificationsAbility to secure and maintain a U.S. Department of Energy (DOE) Q-level security clearance, which requires U.S. citizenship. Bachelor’s degree in mechanical engineering or relevant technical field, or the equivalent combination of education and related experience.Experience and knowledge in the design of facility-related mechanical systems and components such as ventilation systems and associated controls, fire protection systems, liquid nitrogen or argon systems, chilled water systems, or boiler systems.Experience developing mechanical project scope, evaluating design options, determining design criteria, and in preparing and reviewing design and construction specifications, calculations, and drawings that support efficient and successful job completion in industrial facility environments.Knowledge and demonstrated proficiency and experience using of applicable codes and industry standards, e.g., ASME, California Building Code, Uniform Building Code, ASHRAE.Proficient verbal and written communication skills necessary to effectively interact and collaborate in a team environment, including the ability to prepare, present, and explain technical or operational information and to management, reviewers, and stakeholders.Ability to effectively manage, oversee, and assist in the delivery of multiple projects on budget and schedule, often with multiple parallel tasks that require the resolution of conflicting work requirements and prioritization of tasks toward predetermined long- range targets.Additional qualifications at the SES.3 levelAdvanced expertise and significant experience in facility mechanical engineering and industry code compliance.Significant experience with and demonstrated ability to successfully lead and motivate a team in achieving project objectives which include solving highly complex problems, defining and verifying requirements and resources, and applying project management expertise.Significant experience and demonstrated highly advanced skills in project management, budgeting, scheduling, and project tracking.Advanced knowledge and significant experience with various project delivery tools, methods and contract forms; such as design-build and design-bid-build.Advanced communication, facilitation, collaboration, interpersonal, and negotiation skills necessary to effectively present, explain, provide strategic technical advice, build consensus, and influence senior management, external sponsors, regulators, reviewers, and stakeholders.Advanced experience translating highly complex requirements into hardware and software specifications, as well as reading and interpreting mechanical, electrical, and electro-optical specifications, and using drawings, datasheets, and procedure manuals.Qualifications We DesireMaster’s degree in mechanical engineering or related fieldProfessional Engineering registration in mechanical engineering in California or reciprocity from another state within twelve months.Significant experience performing design work for mechanical systems in an architectural engineering (AE) consulting environment.Significant experience with control systems and/or control room design.Significant experience with systems and infrastructure for ventilation systems and the ability to read and develop control system schematics.Proficiency in CAD software (e.g., AutoCAD, Creo), SolidWorks, or other relevant software.Proficiency in power system analysis, fault calculations, coordination, and grounding using SKM Systems Analysis Inc software tools.Pay Range$146,340 - $222,564 Annually

• 146,340 - $185,544 Annually for SES.2 Level
• 175,530 - $222,564 Annually for SES.3 LevelThis is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. Pay will not be below any applicable local minimum wage. An employee’s position within the salary range will be based on several factors including, but not limited to, specific competencies, relevant education, qualifications, certifications, experience, skills, seniority, geographic location, performance, and business or organizational needs.Additional Information#LI-OnsitePosition InformationThis is a Career Indefinite position, open to Lab employees and external candidates.Why Lawrence Livermore National Laboratory?Included in 2026 Best Places to Work by Glassdoor!Flexible Benefits Package401(k)Relocation AssistanceEducation Reimbursement ProgramFlexible schedules (*depending on project needs)Our values - visit Security ClearanceThis position requires a Department of Energy (DOE) Q-level clearance. If you are selected, we will initiate a Federal background investigation to determine if you meet eligibility requirements for access to classified information or matter. Also, all L or Q cleared employees are subject to random drug testing. Q-level clearance requires U.S. citizenship. Pre-Employment Drug TestExternal applicant(s) selected for this position must pass a post-offer, pre-employment drug test. This includes testing for use of marijuana as Federal Law applies to us as a Federal Contractor.Wireless and Medical DevicesPer the Department of Energy (DOE), Lawrence Livermore National Laboratory must meet certain restrictions with the use and/or possession of mobile devices in Limited Areas. Depending on your job duties, you may be required to work in a Limited Area where you are not permitted to have a personal and/or laboratory mobile device in your possession. This includes, but not limited to cell phones, tablets, fitness devices, wireless headphones, and other Bluetooth/wireless enabled devices. If you use a medical device, which pairs with a mobile device, you must still follow the rules concerning the mobile device in individual sections within Limited Areas. Sensitive Compartmented Information Facilities require separate approval. Hearing aids without wireless capabilities or wireless that has been disabled are allowed in Limited Areas, Secure Space and Transit/Buffer Space within buildings.Pre-Placement Medical ExamA job related pre-placement medical examination may be required.How to identify fake job advertisementsPlease be aware of recruitment scams where people or entities are misusing the name of Lawrence Livermore National Laboratory (LLNL) to post fake job advertisements. LLNL never extends an offer without a personal interview and will never charge a fee for joining our company. All current job openings are displayed on the Career Page under “Find Your Job” of our website. If you have encountered a job posting or have been approached with a job offer that you suspect may be fraudulent, we strongly recommend you do not respond.To learn more about recruitment scams: Equal Employment OpportunityWe are an equal opportunity employer that is committed to providing all with a work environment free of discrimination and harassment. All qualified applicants will receive consideration for employment without regard to race, color, religion, marital status, national origin, ancestry, sex, sexual orientation, gender identity, disability, medical condition, pregnancy, protected veteran status, age, citizenship, or any other characteristic protected by applicable laws.Reasonable AccommodationOur goal is to create an accessible and inclusive experience for all candidates applying and interviewing at the Laboratory. If you need a reasonable accommodation during the application or the recruiting process, please use our online form to submit a request. California Privacy NoticeThe California Consumer Privacy Act (CCPA) grants privacy rights to all California residents. The law also entitles job applicants, employees, and non-employee workers to be notified of what personal information LLNL collects and for what purpose. The Employee Privacy Notice can be accessed here.Videos To Watch