How a UXO Watching Brief Supports Geotechnical Work

Geotechnical investigations are a vital early stage in construction projects, providing the data that developers, engineers, and designers need to understand the ground conditions of a site. Boreholes, trial pits, and intrusive ground investigations all help determine whether a location is suitable for foundations, piling, or other structural requirements.

In areas with a history of wartime activity, however, there’s an additional factor to consider: the risk of unexploded ordnance (UXO). Buried bombs, shells, or munitions can still be found across the UK, particularly in urban centres, near former military sites, and on land that was once subject to aerial bombardment or defence activity.

The unexpected discovery of a suspicious object during a ground investigation can bring work to a standstill – sometimes for days at a time. A UXO Watching Brief is designed to prevent this kind of disruption, ensuring that geotechnical projects can proceed safely, efficiently, and with confidence.

What is a UXO Watching Brief?

A UXO Watching Brief provides continuous monitoring of intrusive ground activities by a qualified UXO engineer. Unlike pre-construction UXO surveys, which may not always be practical in certain ground conditions or for certain project types, a Watching Brief relies on real-time visual inspection during the works themselves.

For geotechnical teams, this means an experienced UXO engineer is on site throughout:

• Observing ground-breaking activities such as trial pitting, reduced digs and excavation work.
• Supporting machine operators and engineers with immediate advice.
• Identifying and assessing any suspicious items uncovered.

If ordnance is suspected, the UXO engineer can escalate the situation instantly and implement emergency procedures. If the item is harmless, the team can get back to work without significant downtime.

This approach provides reassurance for contractors and ensures geotechnical investigations can move forward without unnecessary delays.

Why UXO Watching Briefs Matter for Geotechnical Investigations

Geotechnical work is often conducted on tight schedules. Data about soil strength, groundwater conditions, and contamination is essential for design decisions further down the line. A UXO Watching Brief helps keep projects on track in several key ways:

• Minimal disruption: Trial pits and boreholes can proceed with less risk of extended stoppages.
• On-site expertise: Engineers and drillers benefit from direct support from a UXO specialist.
• Rapid response: Potential finds are dealt with quickly, ensuring safety while avoiding long delays.
• Confidence in results: Ground data can be gathered without compromise, supporting accurate analysis and project progression.

In short, a Watching Brief keeps safety and productivity in balance – something that’s crucial for geotechnical contractors working to tight programmes.

Compliance and Best Practice

While there is no single piece of legislation dedicated to UXO management, the Health and Safety at Work Act 1974 and the CDM Regulations 2015 require employers to protect their staff and contractors from foreseeable risks.

The industry standard for managing UXO hazards is set out in CIRIA C681, which provides guidance on assessing and mitigating UXO risks, particularly those linked to WWI and WWII aerial bombardment.

By implementing a UXO Watching Brief, geotechnical teams demonstrate that they are following best practice and taking proactive steps to manage risk.

Why Choose Brimstone for UXO Watching Briefs?

At Brimstone, we understand how critical ground investigations are for the success of construction projects. Our highly trained UXO engineers have extensive experience supporting geotechnical teams across the UK, from small-scale investigations to large infrastructure schemes.

We work seamlessly alongside contractors, providing:

• Practical, real-time reassurance for site teams.
• Tailored solutions that fit with your programme and site conditions.
• Clear communication to ensure that everyone on site understands the risks and procedures.

A UXO Watching Brief with Brimstone gives geotechnical teams the confidence to proceed with their work, knowing that risks are being actively managed from the first bucket of soil to the final borehole.

Planning Geotechnical Investigations?

If you’re preparing for site investigations and want to ensure they progress safely and without unnecessary disruption, Brimstone can help. Our UXO Watching Briefs are designed to support geotechnical projects of all sizes, ensuring your team stays safe, your schedule stays on track, and your data is delivered without delays.

Contact us today to discuss how we can support your next geotechnical investigation.

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