Intrusive UXO Survey_
Intrusive UXO Surveys are essential for the precise detection and identification of unexploded ordnance hidden deep below the surface.
At Brimstone UXO, we utilise advanced technologies and methodologies to conduct thorough and accurate intrusive surveys, ensuring the safety of your project site.
What is an Intrusive UXO Survey_
An Intrusive UXO Survey involves physically penetrating the ground to detect buried ferrous objects that could be unexploded ordnance. This crucial step in the pre-construction phase helps ensure the safety of groundworks by assessing and mitigating the risk of encountering UXO.
Tailored for detecting deep-buried bombs, this survey is ideal for brownfield land or areas with made ground. Achieving greater depths compared to our non-intrusive methods, this survey method provides UXO detection and clearance ahead of individual pile locations, clusters, and borehole works.
As sites have varying requirements due to previous land use, accessibility and soil depth, Brimstone collaborates closely with clients to determine the most suitable surveying method, aligning with project budgets and time constraints. This approach ensures that planned groundwork can proceed in a smooth and safe manner and that UXO risks are mitigated efficiently.
Our CPT Rigs_
We conduct our Intrusive UXO Surveys by using Cone Penetrometer Testing Rigs. These are sometimes referred to as Cone Penetration Testing Rigs or CPT Rigs.
These box-like containers are mounted on a crawler undercarriage, making them ideal for traversing challenging terrain which can be common on construction sites. At Brimstone we own three state-of-the-art CPT Rigs, called Honey Badger, Redfox and Handsome.
The CPT Rig pushes a magnetometer probe into the ground using hydraulic pressure to survey a column of soil. It then uses magnetometry to identify if there are fluctuations caused by ferrous metals, which could be unexploded ordnance. This happens in real-time so our team can abort the survey if a reading is picked up.
Our rigs enable us to survey single pile positions or clusters for deep intrusive works. For large-scale excavations, we can provide a site-wide matrix clearance, offering complete surveying solutions down to the calculated maximum bomb penetration depth of 12 metres.
Benefits of an Intrusive UXO Survey_
Intrusive surveys are a crucial step in ensuring the safety and success of construction projects in areas with potential unexploded ordnance risks:
Imagine the catastrophic consequences if a piling rig were to strike an unexploded bomb hidden beneath the surface — such risks underline the necessity of thorough Intrusive UXO Surveys. By identifying and addressing UXO hazards before construction work begins, we can protect workers and the public from potential harm.
Currently there isn’t legislation in the UK outlining the steps you must take to check for UXO before beginning construction work. There are however legal obligations under the Health and Safety at Work Act 1974 and the Construction Design and Management Regulations 2015 to ensure the safety of employees.
There is also CIRIA C681, the industry guide for the management of risk associated with UXO. The guidance is split into four sections: Preliminary UXO Risk Assessment, Detailed UXO Risk Assessment, Risk Mitigation and Implementation. Brimstone always recommends clients follow the CIRIA C681 guidance, which enables you to reduce the risk of an unexpected UXO encounter.
Our system is triaxial, meaning it models targets in three dimensions. This enables us to get a better understanding of the mass of any suspicious items and quickly rule out metal objects that don’t match the characteristics of the UXO risk on site. Our rigs also allow for more than one pile position to be cleared per one survey position due to their 2 metre survey radius. This reduces the overall number of surveys required and subsequently, the time and cost.
What happens if a suspicious item is identified_
During the Intrusive UXO Survey, real-time data logs are saved and processed, with extensive cleaning, filtering, and correction processes employed to refine the dataset. This is then sent back to our in-house geophysics team at Brimstone’s Head Office for interpretation.
We use a specialist computer model to identify analytical signals and compare them against a bank of known UXO signals. Our team can make estimations of the depth and mass of any suspected item, along with its location in coordinates accurate to 5 centimetres. All of this information is then provided to our clients in a detailed report outlining the survey findings and any recommended further action.
If targets are identified that require investigation, we will recommend that our engineering team is deployed back to site to carry out a target investigation, and that no intrusive works start on site until this has been completed. Alternatively, depending on the client’s requirements, the proposed work might be amended to avoid these targets.
If no anomalies are found, and there are no further recommendations for UXO risk mitigation, you can continue with your proposed works, and we will provide you with a UXO ALARP certificate.
Order an Intrusive UXO Survey_
Don’t compromise on safety when it comes to your construction and development projects. At Brimstone UXO, our Intrusive UXO Surveys provide the precision and thoroughness needed to detect and identify hidden unexploded ordnance, ensuring your site is safe and compliant with industry standards.
When you book a survey with us, our team will ask for a drawing of the proposed pile layout. This will enable our team to calculate the minimum number of surveys that would be required to cover each pile location or parcel of land. It is also worth noting, on sites where there is dense made ground, we might require pre-drilling for the survey positions. This is because our probe can’t push through ground that has brick or concrete fragments. If this is required, our Commercial Team will liaise with you directly.