Construction Mechanical Engineer

At Amentum, we're not just solving problems; we're engineering the future. Our team is driven by an unyielding commitment to innovation, integrity, and collaboration, tackling some of the most significant challenges in science, security, and sustainability. If you're passionate about making a real impact and want to be part of a community that values ethical excellence, this is the place where your ambition can thrive. Here, we believe that success comes from continuously pushing boundaries and working together to deliver on our promises. We embrace challenges with confidence and are dedicated to creating a secure and vibrant future for all. We’ll inspire and empower you to deliver your best work so you can evolve, grow and succeed – today and into tomorrow. We offer an exciting range of opportunities to develop your career within a supportive team who always strive to do the right thing for our people, clients and communities. People are our greatest asset, and we offer a competitive package to retain and attract the best talent. In addition to the benefits you’d expect, UK employees also receive free single medical cover and digital GP service, family-friendly benefits such as enhanced parental leave pay and free membership of employee assistance and parental programmes, plus reimbursement towards relevant professional development and memberships. Work-life balance and flexibility is a key focus area for us. We’re happy to discuss hybrid, part-time and flexible working hours, patterns and locations to suit you and our business. Amentum is a Lot 1 delivery partner within the Decommissioning and Nuclear Waste Partners (DNWP) Framework, a major Sellafield programme worth up to £4.6 billion and running for up to 15 years. The framework is focused on safely accelerating decommissioning, remediation and high‑hazard risk reduction across one of the most complex nuclear sites in the world. Our nuclear team supports the front‑end design, engineering, technical leadership and delivery expertise required across the DNWP portfolio. We are looking for individuals with high‑value expertise from across regulated and comparable sectors to who can work collaboratively, embrace new challenges and contribute to the mission of safely and efficiently delivering Sellafield’s decommissioning and nuclear waste objectives. About the Opportunity The Construction Engineer provides technical, engineering, and planning support to ensure construction works are delivered safely, efficiently, and in accordance with approved designs, standards, and project requirements. Acting as the key interface between design teams, construction supervisors, and project management, the role ensures that engineering intent is correctly translated into safe and compliant site activities. The Construction Engineer supports the development of construction plans, resolves technical issues, maintains quality and HSEQ compliance, and ensures progress is accurately monitored and reported. The role contributes directly to the successful delivery of work packages by providing practical engineering input, maintaining robust control of technical documentation, and driving continuous improvement across construction execution. Typically reports into the Construction Manager. May have direct line management responsibilities for supervisors. Works under the operational direction of the Project Manager on the project / framework being served. Works closely with both professional service colleagues and craft personnel acting as an interface between the two. Roles & Responsibilities: Develop construction plans, schedules, and work programmes. Review design drawings, specifications, and technical documentation for constructability. Coordinate with designers, clients, subcontractors, and project managers to clarify scope and requirements. Support development of cost estimates, bills of quantities, and resource plans. Provide day‑to‑day engineering support to the site team. Ensure construction activities align with approved drawings, standards, and procedures. Verify materials, equipment, and workmanship meet required specifications. Solve technical issues and provide engineering guidance to supervisors and operatives. Ensure safe systems of work are implemented on site. Support the preparation and review of RAMS (Risk Assessments & Method Statements). Ensure compliance with company, client, and regulatory HSEQ requirements. Participate in inspections, audits, and quality checks; close out corrective actions. Track progress against schedule and raise risks/delays promptly. Maintain daily/weekly site records, including labour, plant, and materials. Provide engineering input into progress reports, KPIs, and performance dashboards. Support change control by identifying variations and providing technical justification Communicate clearly with project managers, supervisors, subcontractors, and clients. Manage engineering interfaces between disciplines (civil, mechanical, electrical, etc.). Attend coordination meetings and provide updates on technical or construction matters. Produce or review technical documents such as ITPs, inspection reports, NCR responses, and as‑built drawings. Ensure all engineering documentation is up to date and stored correctly (e.g., SharePoint, ProjectWise). Support commissioning and handover by providing accurate technical records. Identify opportunities for safer, more efficient, or more cost‑effective construction methods. Support lessons-learned exercises and contribute to process improvements. Qualifications & experience: Recognised time served apprenticeship in relevant discipline at NVQ L3. 2 years + experience in an engineering, technical or operational role within a heavily regulated industry. Our Culture Our values are built on a strong foundation of safety, integrity, and respect for every individual. People are at the heart of our mission, and we believe in supporting one another through a culture of care and collaboration. We strive to create a workplace where everyone feels they belong and can thrive. Supporting mental wellbeing and fostering a sense of connection are essential to how we work. When we embrace different perspectives and work together, we become more innovative, more agile, and more successful. We partner with VERCIDA, for greater online accessibility please visit to view and access our roles. As a Disability Confident employer, we will interview all disabled applicants who meet the minimum criteria for a vacancy. We welcome applications from candidates who are seeking flexible working and from those who may not meet all the listed requirements for a role. If you require further support or reasonable adjustments with regards to the recruitment process (for example, you require the application form in a different format), please contact the team.