Nuclear Facility Mechanical Cognizant Systems Engineer

Nuclear Facility Mechanical Cognizant Systems Engineer Entry Level | Full-time Engineering | Livermore, CA | 04/23/2026 Reference #: REF8268X Job Code: SES.2 Science & Engineering MTS 2 / SES.3 Science & Engineering MTS 3 Organization: Engineering 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: A job-related pre-placement medical examination may be required 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. Job Description We have an opening for a Nuclear Facility Mechanical Cognizant Systems Engineer to provide engineering expertise to ensure continued operational readiness of DOE Hazard Category 2 and 3 nuclear facility building structures by maintaining overall cognizance of the integrity of Hazard Category 2 and 3 assigned systems; providing system engineering support for Operations and Maintenance activities (such as facility modifications and equipment installations); and technical support of line management safety responsibilities. The position will report programmatically to the Superblock and administratively to the Defense Technologies Engineering Division (DTED) within the Engineering Directorate. During the employment this individual may be involved in significant research and development (R&D) projects, applying engineering expertise and creating innovative solutions. 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. This position may offer a hybrid schedule, which includes the flexibility to work from home up to one day per week, after a probationary period. The specifics of the hybrid schedule may vary based on the needs of the team and the organization. You will Assist in monitoring the integrity and configuration of mechanical systems to anticipate the need for maintenance, repair, or replacement of components due to aging and degradation. Prepare system logs, surveillance reports, and detailed assessment reports and brief facility management on the results. Identify, monitor, and provide recommendations for the timely procurement and assurance of adequate inventory of spare parts and materials. Utilize comprehensive technical engineering skills and mechanical engineering experience to provide engineering technical support for sustainment, repair, and modification of safety structures, systems, and components. Support significant R&D projects by applying comprehensive level knowledge, skills, and innovation to create mechanical solutions that are safe and compliant with DOE orders and specifications. Develop and implement solutions and approaches for problems and issues of moderate complexity in support of facility operations and maintenance using independent engineering judgment, determining methods, techniques, and evaluation criteria, in-depth analysis, ingenuity, and creativity. Identify and assess the potential impacts to assigned structures, systems, and components from new construction, modifications, and repairs related to other systems, such as HVAC and building structures. Assist in developing and performing technical reviews of facility related procedures, work instructions, and proposed modifications to ensure technical adequacy and feasibility of implementation. Assist in preparing and reviewing mechanical design calculations, drawings, and other documents to describe and provide solutions for complex design requirements and engineering problems, while ensuring compliance with technical criteria, schedules, and deliverables using comprehensive knowledge. Conduct reviews and provide technical input and advice to mid-level internal management, customers, and colleagues on moderately complex system related design, operation, and maintenance issues. Perform other duties as assigned. Additional responsibilities, at the SES.3 level Monitor the integrity and configuration of mechanical systems to anticipate the need for maintenance, repair, or replacement of components due to aging and degradation. Identify, monitor, and provide recommendations for the timely procurement and assurance of adequate inventory of spare parts and materials. Provide engineering technical support for sustainment, repair, and modification of safety structures, systems, and components. Develop and implement solutions and approaches for complex problems and issues in support of facility operations and maintenance using independent engineering judgment, determining methods, techniques, and evaluation criteria, in-depth analysis, ingenuity, and creativity. Support R&D projects by contributing mechanical solutions that are safe and compliant with DOE orders and specifications. Perform technical reviews of facility related procedures, work instructions, and proposed modifications to ensure technical adequacy and feasibility of implementation. Prepare and review mechanical design calculations, drawings, and other documents to describe and provide solutions for complex design requirements and engineering problems, while ensuring compliance with technical criteria, schedules, and deliverables. Conduct reviews and provide technical input and advice to mid-level internal management, customers, and colleagues on complex system related design, operation, and maintenance issues. Qualifications Ability to secure and maintain a U.S. DOE Q-level security clearance which requires U.S. citizenship. Bachelor’s degree in mechanical engineering or equivalent level of education and related technical experience. Comprehensive knowledge of mechanical engineering standards and practices, such as ASME, ANSI, NFPA, etc. Broad experience with and comprehensive knowledge and skills in the design, modification, and evaluation of mechanical systems for buildings and facilities, such as piping, heating, ventilation, and conditioning. Comprehensive knowledge of and demonstrated proficiency and experience in developing or reviewing calculations, specifications, drawings, and sketches; determining design criteria for modifications, renovations, and upgrades on small projects and on occasional larger projects. Proficient verbal and written communication skills necessary to effectively interact and collaborate in a team environment, including the ability to identify, develop and effectively communicate recommendations to facility and senior management regarding facility and safety equipment modifications. Proficiency and experience with developing work process documents and safety documentation. Experience working in a multi-disciplinary team environment which includes scientists, engineers, and technicians with demonstrated ability to effectively manage, oversee, and deliver 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 level Significant experience in mechanical systems for buildings and facilities and industry code compliance, including Department of Energy requirements for nuclear facilities. Advanced knowledge of mechanical engineering standards and practices, such as ASME, ANSI, NFPA, etc. Significant experience with and advanced knowledge and skills in the design, modification, and evaluation of mechanical systems for buildings and facilities, such as piping, heating, ventilation, and conditioning. Advanced knowledge of and demonstrated significant experience in developing or reviewing calculations, specifications, drawings, and sketches; determining design criteria for modifications, renovations, and upgrades on small projects and on occasional larger projects. 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. Advanced communication, facilitation, and 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. Qualifications We Desire Master’s degree in mechanical engineering or related field. Professional Engineering Registration in Mechanical or Nuclear Engineering in California or reciprocity from another state within twelve months. Significant experience working with mechanical structures, systems, and components in a nuclear environment. Significant experience preparing project estimates. Proficiency in CAD software (e.g., AutoCAD, Creo). Pay Range

• 146,340 - $222,564 Annually
• 146,340 - $185,544 Annually for the SES.2 level
• 175,530 - $222,564 Annually for the SES.3 level

This 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. Position Information This is a Career Indefinite position, open to Lab employees and external candidates. Security & Compliance Requirements This position requires a Department of Energy (DOE) Q-level clearance. If selected, the Agency will initiate a Federal background investigation to determine eligibility for access to classified information. All DOE Q cleared employees are subject to random drug testing. Pre-Employment Drug Test External 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. Pre-Placement Medical Exam A job-related pre-placement medical examination may be required. Reasonable Accommodation Our 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. Equal Opportunity Statement We 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. Privacy Notice The 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. #J-18808-Ljbffr Lawrence Livermore National Laboratory