Senior Mechanical Engineer

We Served; Whitehaven; Hybrid; GBP 100,000 - GBP 125,000; Full time

Job summary

A leading nuclear engineering firm in the United Kingdom is seeking a Senior Mechanical Engineer to lead engineering tasks in a major nuclear decommissioning program. This role involves applying advanced technical expertise and mentoring junior engineers while ensuring compliance and safety across projects. The ideal candidate will have a relevant engineering degree and demonstrated multidisciplinary teamwork experience. This position offers a competitive compensation package along with generous benefits, including a matched pension contribution and flexible working arrangements.

Benefits

Generous holiday allowance

Matched contribution pension scheme

Access to a Digital GP

Employee assistance programme

Holiday Trading

‘Be Kind Day’ for volunteering

Responsibilities

• Lead the delivery of complex mechanical engineering tasks.
• Produce and review engineering documentation.
• Build strong relationships with customers.
• Apply relevant procedures to ensure safety and compliance.
• Identify and manage project risks.

Skills

Delivering engineering activities across project lifecycle

Producing and reviewing detailed engineering documentation

Working effectively in multidisciplinary teams

Excellent communication skills

Education

Engineering degree (or equivalent) in relevant engineering discipline

Job description

Overview

Job Title: Senior Mechanical Engineer
Location: Whitehaven, Cumbria + Hybrid Working Arrangements
Compensation: Competitive Salary + Benefits
Role Type: Full time / Permanent
Role ID: SF68226

Lead the Engineering That Shapes the Future of Nuclear Decommissioning

At Cavendish Nuclear, we’re working to create a safe and secure world, together. If you join us, you can play your part as a Senior Mechanical Engineer at either of our Westlake’s Science Park, Moor Row or Warrington, Cheshire sites.

The role

As a Senior Mechanical Engineer, you’ll be a key contributor to one of the UK’s major civil nuclear decommissioning programmes. You’ll take a leading role within a multidisciplinary engineering team, applying advanced technical expertise to develop, integrate, and enhance complex mechanical systems that directly support the safe deconstruction and futureproofing of nuclear facilities.

Your work will influence high‑impact engineering decisions, ensuring compliance, technical excellence, and robust design integrity across the full project lifecycle. You’ll also support the development of junior engineers, collaborate across functions, and help shape best‑practice engineering within one of the most respected nuclear design alliances in the UK.

Day-to-day, you’ll have the following responsibilities:

• Lead the delivery of complex mechanical engineering tasks and provide high‑quality technical guidance
• Produce and review engineering documentation, including calculations, drawings, models, and reports
• Build strong relationships with customers and act as a key technical interface
• Apply relevant procedures, codes, and standards to ensure safety, compliance, and technical rigour
• Identify and manage project risks while contributing to safety assessments and continuous improvement initiatives.

This is a full‑time position working 37 hours, 5 days per week based at either of our Westlake’s Science Park, Moor Row or Warrington, Cheshire sites.

Essential experience

• Proven experience delivering engineering activities across the full project lifecycle
• Strong track record of producing and reviewing detailed engineering documentation
• Demonstrated ability to work effectively in multidisciplinary teams
• Excellent communication skills with confidence engaging customers and stakeholders.

Qualifications

• Engineering degree (or equivalent) in a relevant engineering discipline.

Security Clearance

The successful candidate must be able to achieve and maintain Standard (BPSS) security clearance for this role. Further details are available at United Kingdom Security Vetting: clearance levels - GOV.UK (gov.uk)

What we offer

• Generous holiday allowance
• Matched contribution pension scheme, with life assurance
• Access to a Digital GP, annual health check, and nutritional consultations through Aviva DigiCare+
• Employee share scheme
• Employee shopping savings portal
• Payment of Professional Fees
• Reservists in the armed forces receive 10-days special paid leave
• Holiday Trading is a benefit that allows UK Cavendish employees to buy additional leave or to sell up to one working week of annual leave from their annual entitlement. This Window opens February through to March annually.
• ‘Be Kind Day’ enables employees to take one working day\'s paid leave a year (or equivalent hours) to undertake volunteering work with their chosen organisation or registered charity
• Excellent development opportunities and benefits package including an employee assistance programme supporting physical, mental and financial wellbeing.

Cavendish Nuclear

As a leader within the UK nuclear industry, Cavendish Nuclear, part of Babcock International Group, provides a comprehensive range of critical nuclear solutions in clean energy, defence and civil new build and decommissioning projects. Together, we’re innovating to make nuclear safer, faster and cost-effective across the nuclear energy life cycle. Your career with us could take you anywhere within Babcock International Group – from Canada, the USA to Japan. Work with us to create a safe and secure world, together.

We are a disability confident committed employer. If you have a disability or need any reasonable adjustments during the application and selection stages, please email [e-mail] with the subject header ‘Reasonable adjustments requirement’. We’re committed to building an inclusive culture where everyone’s free to thrive. We are happy to talk about flexible working – please ask about alternative patterns of work at interview.

Closing date

Closing date: 17/02/2026

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