Unexploded Ordnance (UXO) Survey and Risk Mitigation

Unexploded Ordnance (UXO) Survey and Risk Mitigation

Unexploded bombs, mines, and other munitions continue to pose a serious threat to people and property around the UK. Fortunately, there are steps that can be taken to mitigate the risk that UXO presents and allow for safe development on or near sites where UXO may be present.

UXO contamination can be present in a variety of forms, such as bombs, grenades, mines, artillery shells, and other explosive devices. These relics from past conflicts can still contain live explosives that could cause harm if disturbed.

In order to ensure the safety of workers and the public during construction or development projects, it is essential to identify and assess potential UXO hazards before beginning any work.

SEP Geophysical has the experience and expertise to provide comprehensive UXO risk mitigation surveys, emphasising the importance of conducting thorough research and a detailed UXO risk assessment.

Our expertise in UXO risk mitigation extends across various projects, from small housing developments to large-scale wind farm developments in both terrestrial and marine settings. Our team of experienced professionals will work with you to ensure that your project is completed safely and on schedule.

SEP Geophysical are able to assist with any steps along the process such as:

Organising and interpreting a UXO desk study

Before ground works can begin, a UXO risk assessment should be conducted to identify any areas of higher risk and detail further action required to mitigate any risks. Conducting a preliminary UXO risk assessment is a critical step in identifying areas of higher risk.

The UXO risk assessment is achieved by reviewing all available information and data, including records from national archives, to identify any hazards that may be present and assess the potential risk of explosive ordnance. A detailed UXO risk assessment is generally required for sites with a history of military usage.

A UXO risk assessment will help to:

  • Establish the likelihood of hazards present
  • Identify any areas that may need further investigation
  • Develop a suitable UXO management plan
  • Reduce the overall risk on-site
  • Protect the safety of workers, the public and the environment

Where further investigation is identified as being required, SEP Geophysical offer a comprehensive UXO geophysical survey service to search for and locate any potential UXO items.

Non-intrusive geophysical survey, data collection and interpretation

Our team are experienced in the use of a variety of geophysical survey techniques to locate targets and reduce UXO risk. This includes Magnetometry, Electromagnetics (EM), and Ground Penetrating Radar (GPR). All data collected is processed and interpreted by our experienced team of geophysicists, who are experienced in interpreting large and complex data sets.

For detecting deep-buried UXO, intrusive surveys serve as an alternative method, employing techniques like magnetometers and boreholes to penetrate the ground, contrasting with the non-intrusive approaches discussed above.

UXO Reporting

A comprehensive UXO report is then generated which includes:

  • A review of the available information and data
  • The results of the geophysical surveys conducted
  • An interpretation of the data collected
  • Recommendations for further action (if required)

This report forms the basis for any further UXO risk mitigation that is required.

UXO Borehole Clearance (Down-hole magnetometer survey)

Where required, we also offer a borehole clearance service, a type of intrusive UXO survey, to check for the presence of potential UXO during drilling operations. Intrusive UXO surveys, including our borehole clearance service, are essential for detecting deep-buried UXO and providing clearance for intrusive works ahead of piling or boreholes. This is achieved by lowering a magnetometer into the hole on a wire-line system at set intervals to progressively review ahead of further drilling.

Support the Removal and Disposal of UXO

Once any potential UXO items have been located, our team can liaise with appropriate authorities and expedite the safe removal of UXO targets.

Unexploded Ordnance (UXO) Survey FAQs


What is unexploded ordnance?

Unexploded ordnance is an explosive device that has been primed, fused, armed, or otherwise prepared for use, but has failed to function as intended. UXO may include bombs, grenades, rockets, missiles, shells and other explosive devices. Although most UXO dates back to the First and Second World Wars, it can also be found on sites that have been used for military purposes more recently.

What is a UXO survey?

A UXO survey is conducted to search for and locate any potential UXO items that may be present on a site. This is generally performed following the risk assessment to confirm the level of assessed risk posed by UXO and to inform any future action that may be required.

Why do I need a UXO Risk Assessment?

UXO continues to pose a risk to both workers and the public, even many years after it was first used. Conducting detailed UXO risk assessments is crucial in identifying whether action is required before ground works can begin. 

These assessments offer thorough archival research and expert on-site investigation, ensuring a comprehensive understanding of potential risks. Moreover, more detailed research is often necessary, particularly in assessing the risk of UXO from other military operations not reflected on the provided maps. 

This emphasises the importance of not solely relying on maps and suggests seeking additional information or conducting a free pre-desk study assessment to confirm the need for further research. 

Geophysical survey techniques can then be used to locate any potential items that may be present, as there is a risk that UXO could be present and pose a danger to workers on the site. UXO risk assessments serve as a key service in identifying and mitigating UXO risks, highlighting our track record in performing these assessments for various clients.

How does a UXO survey work?

A survey is carried out using specialist equipment to detect the presence of buried objects that could be UXO. This is generally done using geophysical survey techniques such as magnetometry, electromagnetics (EM), or ground penetrating radar (GPR). Data from the survey is then interpreted by experienced geophysicists to produce a report that can be used to inform and determine if additional action is needed on site.

How much does a UXO survey cost?

The cost will depend on a number of factors, including the size and complexity of the site, the type of geophysical survey techniques used, and the interpretation of the data collected. Generally, costs can range from a few thousand pounds to tens of thousands of pounds.

Get in Touch

Always utilising the highest specification equipment such as the industry-standard caesium vapour magnetometers and proprietary data analysis software, SEP Geophysical are highly experienced and ready to assist with UXO mitigation requirements.

If you have any questions about UXO surveys or would like to discuss your specific requirements, our team of experts are on hand to provide practical advice and support. Please do not hesitate to get in touch.