Senior Mechanical Engineer - COMAH

Permanent | Competitive Salary + Benefits

Location: Thurrock

Are you an experienced Mechanical Engineer with experience working in a COMAH environment, looking to step into a role where you can directly shape engineering standards, influence investment decisions, and drive meaningful improvements across multiple sites? This is an exciting opportunity to join a well-established yet fast growing and agile organisation during a period of significant capital investment and site development.

As Senior Mechanical Engineer, you'll become the mechanical engineering focal point across a high-hazard, top-tier COMAH environment. With major multi‑million‑pound projects underway, ongoing upgrades to ageing infrastructure, and an engineering function modernising its systems and standards, this role offers the chance to genuinely leave your mark.

You’ll work closely with the leadership team and collaborate with discipline engineers, project managers, plant inspectors, maintenance teams and external specialists to ensure safe, reliable and efficient operation of a broad range of mechanical assets - from rotating equipment and pressure systems to boilers, vessels, compressors and site utilities.

This is a technically varied, hands‑on role with strong strategic influence.

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• Leading mechanical engineering activities across the site, with wider support to other UK facilities.
  
• Providing expert input to the design, specification, installation and commissioning of new plant, equipment and modifications.
  
• Supporting inspection teams with critical equipment assessments, developing repair scopes and contributing to mechanical integrity strategies.
  
• Updating and improving mechanical engineering standards, specifications and procedures across the business.
  
• Partnering with Maintenance to develop preventive and predictive maintenance strategies that reduce downtime and improve reliability.
  
• Troubleshooting complex mechanical issues and providing solutions that support safe and efficient production.
  
• Conducting risk assessments, RCAs, reliability studies and participating in HAZOPs, MoCs and similar safety reviews.
  
• Supporting capital projects – from early scoping through budgets, contractor oversight and installation.
  
• Ensuring robust documentation through collaboration with document control and CAD design teams.
  
• Driving continuous improvement to enhance plant reliability, performance and energy efficiency.
  

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• Degree in Mechanical Engineering.
  
• Chartered Engineer (CEng) or working towards chartership.
  
• Proven experience in a senior mechanical engineering role within a Chemical, Oil & Gas or similar heavy industrial setting – Upper Tier COMAH experience is essential.
  
• Strong knowledge of rotating equipment, pressure systems, piping design and relevant industry codes (ASME, API, EEMUA, etc).
  
• Background in reliability engineering, mechanical integrity and maintenance best practice.
  
• Experience contributing to or delivering engineering work within multi‑million‑pound capital projects.
  
• Excellent communication, organisation and problem‑solving skills with the ability to influence and engage across functions.
  

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• A chance to shape the mechanical engineering function within a growing, well‑invested business.
  
• Exposure to major capital projects and meaningful engineering challenges.
  
• An agile organisation where decisions are made quickly, and engineering expertise is valued.
  
• The opportunity to mentor, guide and elevate standards across the wider engineering team.
  
• A top‑tier COMAH environment where your work directly enhances safety, reliability and long‑term asset health.
  

If you’re an experienced mechanical engineer looking for a role with depth, autonomy and impact, we’d love to hear from you.

Apply today and help drive the next wave of engineering excellence across the business.

Our client is an equal opportunities employer and we encourage applicants from all backgrounds.