Site Engineer – Mannington 400kV Substation (BH21) Location: Mannington, Dorset Rate: £400 per day Contract Type: Full-time, site-based contingency worker IR35 Status: Outside IR35 Duration: 6-month rolling contract (12-month programme) Hours: Monday to Friday, 10-hour days, occasional travel to client offices MRR Infrastructure is proud to be supporting the delivery of a significant 400kV substation scheme for a leading global engineering and construction consultancy, recognised for its technical excellence and long-standing success within the power transmission and distribution sector. This opportunity offers the chance to contribute to a high-profile National Grid project, working alongside a multidisciplinary team to maintain the highest levels of safety, quality, and technical performance throughout delivery. We are seeking a proactive Site Engineer with a strong background in substation infrastructure projects to provide on-site technical support, oversee setting out, verify works against design, and ensure compliance with all relevant construction standards and procedures. You will liaise closely with subcontractors, the client and project managers, playing a pivotal role in delivery assurance, temporary works, QA documentation, and supporting safe systems of work. You will be responsible for maintaining records, updating as-built documentation, managing technical queries, and assisting in the coordination of construction activities to meet programme targets. A strong understanding of National Grid processes, civils integration, and the ability to communicate effectively with all stakeholders is essential. Essential Qualifications & Experience * CSCS or CCNSG Safety Passport * National Grid Person * SMSTS, SSSTS or IOSH Managing Safely certification * Minimum 5 years’ experience in the T&D industry on substation projects * Proven background in setting out, QA and drawing management * Temporary Works Coordinator or Supervisor experience * Full UK driving licence Desirable: National Grid Competent Person NSI 6 & 8, EUSR HSG47, First Aid certification, IOSH Environmental or equivalent. This is a site-based role requiring excellent judgement, the ability to analyse technical challenges, and a practical approach to solving problems. The successful candidate must be confident navigating high-voltage substation environments, interpreting construction drawings and specifications, and ensuring construction works align with client expectations, statutory regulations and internal procedures. This is an excellent opportunity for a technically capable Site Engineer to work on a nationally significant infrastructure scheme with long-term potential