Principal Mechanical Engineer (Nuclear Mechanical Handling)

Following a number of project and long term framework wins in the Nuclear industry, including Urenco, we are seeking a Principal Mechanical Engineer to support and deliver key elements of design work on projects, primarily through the management of technical resources to deliver on company and client promises. Costain’s multi-disciplinary engineering and design team delivers comprehensive design solutions across a range of UK Infrastructure sectors - Energy, Defence & Nuclear, Water, Rail, Roads and Integrated Transport. The team covers the full project lifecycle from feasibility and concept through to detailed design and construction support. We focus on the delivery of sustainable, future ready and safe-by-design outputs with a strong constructability ethos. Typical deliverables and activities for the Mechanical Engineering team include: Specifications and Datasheets for Mechanical Equipment Enquiry and Purchase Requisitions for Mechanical Equipment Packages. Technical Bid Evaluations for Mechanical Equipment Packages. Vendor documentation review and FAT attendance for Mechanical Equipment Packages. Mechanical Handling and Lifting equipment Specification and design HVAC & Building Services design Plant and Mechanical Equipment Layout Pumping system calculations Pressure Equipment design calculations and Mechanical Equipment stress analysis As a Principal Mechanical Engineer, you will be responsible for delivering key elements of design work on projects, primarily through the management of technical resources to deliver on company and client promises. This role requires significant technical interface management between delivery teams, driving progress, ensuring compliance and quality, and resolving complex challenges. You may act as the single point of contact for the project discipline team, hold budget and resource responsibility, and maintain line management duties while executing hands-on design production, checking, and approval. This role will make a key contribution to development of Costain’s capability in the specialist area of Nuclear Mechanical Handling to support exciting projects for a number of clients based in North and North West England. Hybrid role typically involves working three days a week in the Manchester or in our clients office in Cheshire with a flexible approach to home working to promote wellbeing. #LI-MR1 Technical Leadership: Provide direct line management for a group of engineers/designers, including performance reviews, upskilling, mentoring, and reward coordination with the Discipline Manager. Project Delivery: Act as the single point of contact for project disciplines, taking responsibility for technical compliance, quality, resource planning, and budget performance. Technical Review & Approval: Execute the production, checking, and approval of engineering deliverables (calculations, scopes of work, specifications) aligned with your discipline. Interface Coordination: Coordinate project work activities between multi-disciplinary teams, clients, and construction teams, leading meetings and managing change control. Estimation: Lead the development of robust estimates (scoping, hours, risks, assumptions) for tendering/project change, ensuring outcomes align with project and client targets. Leadership Support: Actively learn and share best practices across the team, champion safety performance. Provide technical guidance, mentoring, and support to Engineers and junior team members, and deputise for Discipline Managers when required Knowledge, Skills, and Experience Essential Extensive engineering design experience across the full engineering lifecycle (from tendering to close-out) within a design consultancy or contractor environment. Leadership Support and mentoring experience with the ability to support career development. Proficient in project reporting data (KPIs, carbon tracking, change management, and risk/opportunity reporting). Extensive working knowledge of the UK Regulatory framework associated with the discipline (e.g., CDM, PESR, Machinery Safety Regulations, ATEX). Extensive working knowledge of relevant design codes and standards (e.g. BS EN, API, ASME, WIMES, CIBSE / ASHRAE etc). Excellent organisation, communication, and time-management skills with a collaborative approach. Experience in the following specialist mechanical engineering fields: Nuclear Mechanical Handling Experience with the following mechanical engineering and design deliverables and activities: Technology Readiness Level Single Discipline Design Review Multi Discipline Design Review Design Justification Report Mechanical Handling Diagrams Design Proposal Drawings Plant and Building Layout Equipment Specifications and Datasheets Desirable Experience with supply chain management and in site/construction environments. Experience in multiple sectors and an innovative approach to driving new engineering delivery methods. Strong working knowledge of stress analysis methods and software. Extensive knowledge and experience in one or more specialist areas of mechanical engineering design and delivery (e.g. wastewater pumping systems and treatment technologies, rotating or static process equipment, mechanical handling and lifting equipment, stress analysis methods and software, HVAC & Building Services design). Experience with Costain clients i.e. Urenco Capenhurst Essential Degree qualified in a relevant engineering discipline (ideally 2:1 or better) or equivalent educational experience. Professional qualifications such as Chartered Engineer (CEng) or Incorporated Engineer (IEng) status. Valid safety passport or industry equivalent. BPSS holder, capable to obtain SC security clearance - UK Citizen or 5 years UK residency Desirable Advanced technical training or post-graduate qualifications. Fellowship of relevant professional body. (or working towards). SC security clearance holder