Anomaly Detection: A Guide to UXO Surveys with Brimstone UXO

A UXO survey is a critical process used to detect anomalies beneath the ground that may be unexploded ordnance (UXO). These site-based investigations are essential for identifying potential hazards before any groundworks begin, reducing the risk of accidental detonation during construction or excavation works.

At Brimstone UXO, we carry out both intrusive and non-intrusive UXO surveys, using advanced technology to deliver accurate and reliable results. Our highly trained in-house geophysics team then analyses the survey data, comparing the characteristics of detected anomalies against the known signatures of unexploded ordnance.

By conducting comprehensive UXO surveys, we help clients ensure their sites are safe, compliant with health and safety regulations, and ready for development.

Non-Intrusive UXO Surveys: scanning large areas efficiently

Non-intrusive UXO surveys are a fast and effective way to assess large areas, detecting potential UXO without disturbing the ground. This method is particularly suitable for greenfield sites or areas where ground disturbance must be minimised.

The technology behind Non-Intrusive Surveys

We use state-of-the-art equipment, fitted with magnetometers, to penetrate up to six metres below the surface. These instruments measure subtle variations in the Earth’s magnetic field, highlighting potential metallic anomalies that could indicate UXO.

For larger sites, we deploy towed array systems, where an all-terrain vehicle (ATV) pulls an eight-channel system across the area. This method increases efficiency, allowing us to cover more ground in less time. On smaller or more confined sites, we use a pushcart system with a five-channel gradiometer, offering flexibility without sacrificing accuracy.

When Non-Intrusive Surveys face limitations

While non-intrusive methods are effective for most landscapes, some terrains, such as heavily vegetated areas or uneven ground, can be difficult to access. In such cases, we turn to drone technology, offering an aerial solution for UXO detection.

Drone UXO Surveys: versatile aerial solutions

Drone-based UXO surveys are a form of non-intrusive investigation that allows us to cover extensive and hard-to-reach areas. This approach is particularly valuable for remote or rugged terrain, where ground-based surveys are impractical or unsafe.

Cutting-edge drone technology

Our UAVs (unmanned aerial vehicles) are equipped with advanced sensors capable of detecting anomalies up to four metres below the surface. The drones operate efficiently in various weather conditions, including wind, rain, and high temperatures, making them a reliable option year-round.

In addition to standard magnetometry, our drone surveys can incorporate:

• Photogrammetry: Creating detailed, high-resolution 3D maps of the terrain.
• LiDAR (Light Detection and Ranging): Using laser pulses to generate precise topographic data, even in areas with dense vegetation.
• Gamma Radiation Detection: Identifying sources of gamma radiation, which are then analysed against isotopic changes in the local environment.

Drone surveys significantly enhance efficiency, covering up to five times more area than ground-based methods, making them ideal for large-scale or time-sensitive projects.

Intrusive UXO Surveys: going deeper for accurate results

When the landscape or ground conditions prevent effective non-intrusive surveys, or if the identified UXO risk is for deep buried bombs, we carry out intrusive UXO surveys. This method is particularly suitable for brownfield sites, former industrial areas, and land containing reworked soil or landfill material.

How Intrusive UXO Surveys work

We use Cone Penetration Testing (CPT) rigs or similar equipment to push probes deep into the ground using hydraulic pressure. These probes can penetrate up to 25 metres – far beyond the reach of non-intrusive methods – providing detailed subsurface data.

As the probe descends, it captures high-resolution data, which is used to create a 3D model of the subsurface. This allows our geophysics team to accurately locate and assess any anomalies that could indicate UXO.

Next steps if UXO is detected

If our UXO survey identifies an anomaly with characteristics consistent with unexploded ordnance, our Operations Team will contact you promptly. We will discuss the findings and outline the next steps for UXO risk mitigation, ensuring the site is made safe before further work continues.

Why choose Brimstone UXO for your UXO survey?

At Brimstone UXO, we combine industry expertise with cutting-edge technology to deliver reliable, high-quality UXO surveys. Our experienced geophysicists, survey teams, and operations specialists work together to help you meet health and safety requirements while keeping your project on track.

If you need a UXO survey, contact Brimstone UXO today. Our expert team will guide you through the process and ensure your site is surveyed thoroughly and efficiently.

To book a survey:

• Email our Commercial Team at enquire@brimstoneuxo.com.
• Call us on 020 7117 2492.

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