Job Description

ACTEMIUM Design offers multidiscipline design expertise which enables us to deliver robust solutions to our customers on mission critical and strategically important projects. As part of VINCI Energies with a turnover of EUR14 billion, ACTEMIUM Design UK is an agile business, growing in a dynamic and sustainable manner.


We are recruiting a Senior / Principal Mechanical Engineer to author Mechanical Design Substantiation Reports which will underpin the design of the various process systems. In this first instance this role will be a seconded position with the client.

Staff or Contract (within IR35) options available.

Background to the role

Actemium Design UK is currently producing the design of the Process Plant and Equipment (PP&E) to deliver an enduring manufacturing capability for a key customer in the defence industry. Acting as an Intelligent Client (IC) on behalf of the customer, we liaise with the suppliers of professional services and equipment vendors to ensure consistency and standardisation in the design of the process systems.

The Role

Authoring nuclear substantiation documentation, including Design Substantiation Reports (DSR) providing the assurance and evidence to enable confidence in our technical solutions. Reviewing safety case documentation and identifying potential shortfalls in the design Liaising with both internal and external designers and equipment vendors to gather information. Interrogating the Engineering Schedule and evidencing claims made against Systems, Structures, and Components (SSC) in the documentation. Interfacing with other stakeholders such as Human Factors, Fire Safety, Criticality, Radiological and the client Technical Authority.

The Person

Questioning attitude, confident to challenge information where needed. Previous experience in design substantiation and safety case involvement for highly regulated industries. Fully familiar with all aspects of safety case methodologies and legal framework relevant to nuclear safety. Good oral and written communication skills, including presentation and report writing. Several years' experience working in design engineering. Degree with honours or Level 6 equivalent. Chartered Engineer or equivalent (or working towards).

About ACTEMIUM Design

ACTEMIUM Design, a trading name of North West Projects Limited, has over 35-years' experience of multidiscipline engineering design across the full project lifecycle, including support through manufacture, testing and installation/commissioning in both the nuclear and non-nuclear environment.





Our work is underpinned by our core values:

Trust and Empowerment

Placing confidence in others enabling full potential.

Team Spirit and Generosity

True togetherness and willingness to share success.

Integrity & Responsibility

Doing the right thing, consistently honest & transparent.

Innovation & Entrepreneurship

New ideas whilst developing long term customer relationships.

Why choose ACTEMIUM Design?

We offer a competitive salary package to attract and retain high performing talent. Innovative, collaborative and inclusive environment. Flexible working including hybrid and core hours patterns. Professional and skills based continued development though training and mentoring. Professional Membership fees. Employee share scheme. EV salary sacrifice scheme. Health Shield Cover. Modern offices with on-site gym, cafe (Chorley Head office). Social events, charity fundraising events throughout the year. Signatory to the Armed Forces Covenant.

Additional Information

Due to the nature of our work, some roles require applicants to be able to achieve and maintain security clearance criteria. This means that your eligibility for certain roles may be affected by your place of birth, nationality, current or former citizenship, and any residency you hold or have held. Further details are available at United Kingdom Security Vetting: clearance levels - GOV.UK (www.gov.uk).


If you require further support or reasonable adjustments with regards to the recruitment process, please let us know.