Site Investigation

SafeLane Global recently acquired five Raeburn Group companies, allowing it to extend its impressive service range. SafeLane now offers turnkey site investigation solutions for the entire pre-construction phase. For ease of understanding, these services can be divided into three sections: understanding a site | investigating and evaluating | delivering the project.

SafeLane Global has been providing explosive threat mitigation services for over 30 years.  Following its acquisition of WB+AD Morgan and five Raeburn Group companies (Raeburn Drilling & Geotechnical, Raeburn Drilling Northern, DTS Raeburn, Terra Tek, and Allied Exploration & Geotechnics), SafeLane now offers turnkey site investigation solutions for the entire pre-construction phase in the UK. 

Site investigation solutions

SafeLane offers three main service umbrellas to help you, our client, understand your site in the detail necessary to address various sub-surface hazards, identify and assess where hazards pose plausible risks, provide accurate ground information relating to the soil and rock sequences encountered including geotechnical parameters and the evaluation of contaminative impacts.  This provides you with confidence, and ensures successful outcomes during the planning, design and delivery phases of a development or construction programme.

For simplicity regarding the service offering available, SafeLane’s site investigation solutions are divided up into three main areas: understanding the site, ground investigation and evaluation, and the delivery of the project.

Read on to discover more, or contact us for immediate assistance.

1 – Understanding the Site

Services that are encompassed in this category are offered throughout the group. 

1a – Risk Assessments:

Flood Risk Assessments (FRAs)

FRAs are necessary when working on sites that are at risk of flooding or for developments that are larger than a hectare in size. 

The SafeLane Group offers a quantitative appraisal service to determine whether a site is at risk of flooding, or if a development will cause associated or adjoining areas to be impacted by flooding. 

Coal Mining Risk Assessments (CMRAs)

Coal mining risk assessments s are required for developments planned in coal field areas because of the latent risk posed by sub-surface historical mining activities which can lead to issues of subsidence and fugitive gas movement to the surface. 

Various historical features (such as abandoned shafts, adits, staples and mine workings) can cause significant risk to new and existing developments.  By using a variety of desk based resources and liaison with the Coal Authority, SafeLane can assess the risk posed to sites and existing property holdings from historical mining activity.

The CMRA informs the requirements of an intrusive mining investigation which is undertaken using the techniques outlined in the Ground Investigation and Evaluate section (below) to confirm and assess the risk posed by historic mining activities. 

The work is carried out under Coal Authority license and follows applicable guidance in order to mitigate hazards identified.

Preliminary / Detailed UXO Risk Assessments

SafeLane Global offers two types of risk assessments regarding unexploded ordnance (UXO).  The first is a preliminary risk assessment (PRA) which constitutes a report detailing the likelihood of encountering UXO within a particular search area, such can be instantly generated using a postcode or other locational information.   

The second, usually used as a follow-up to a PRA (but which can be obtained without a PRA) is a detailed risk assessment which utilises a broad variety of historical sources to gain more information about potential UXO risk and provide mitigation solutions for maintaining safe intrusive and construction related operations.

Ground Gas Risk Assessment (GGRA)

Gases that emanate from the ground, be they natural or man-made, can be toxic, flammable, explosive, or asphyxiating.  This  issue, often in mining areas, on or near previous landfills and other types of environmental setting, can pose a plausible risk factor to construction workers and post development end-users. 

SafeLane Global can assess the risk of hazardous ground gases present on your site, monitor the gas, and offer recommendations or solutions to mitigate risk levels. Long-term assessment methodologies can be undertaken using down-hole automated data logging devices to capture gas fluctuations over a range of atmospheric conditions and induced flow due to in-ground indirect driver mechanisms (e.g., groundwater movements).  

Generic / Detailed Quantitative Risk Assessments for Ground Contamination

Contaminated land can cause harm to human health, damage to ecosystems, impact land usefulness and quality as well as affect water supplies. 

SafeLane Global can identify potential sources of contamination on your site, detail the impact it may have and recommend remediation solutions in order to mitigate the risk.

1b – Ground Investigation Associated:

Pollution Prevention and Control (PPC) & Site Surrender Reports

PPC baseline surveys create a benchmark for your site’s land condition from the perspective of contamination.  These are often required when a site changes ownership or for environmental permitting legislation in relation to PPC directives.

The baseline land contamination conditions can inform planning and development regulators of current risk factors or constraints to building activities and thereby land value. Similarly, on surrender, occupiers may require a complimentary study to confirm that the land has not been unduly impacted by their activities.

Groundwater Studies & Hydrological Modelling

Groundwater studies can be utilised to determine the impact of a project on groundwater conditions and how groundwater issues can impact a project. 

1c – UXO Threat Mitigation:

For more information on our UXO services, visit our comprehensive UK UXO page!


2 – Investigate and Evaluate

SafeLane Global offers three main service components to assist clients with investigating and evaluating their sites: drilling and probing, on-site testing, geotechnical and chemical testing and monitoring.

These services are offered at a number of SafeLane Global Group locations throughout the UK, with investigation operations undertaken in a wide range of industrial and environmental settings both on-land and over water (near shore).

2a – Drilling & Probing

Sonic Drilling

The group owns 5 No LS 250 Rota-Sonic drilling rigs, capable of achieving vertical depths of 78m below ground level as well as at angles between 45 below horizontal to 90 vertically. 

Sonic capabilities offer a fantastic alternative to more conventional techniques that are often less successful in achieving samples for testing, thus providing reliable and robust on-site testing information and depth penetration where more challenging ground conditions occur (such as in dense sands and gravels and coble/boulder bearing strata).

Our LS 250 rig has also recovered samples of milled steel captured within made ground.

The sampling system utilitised by the LS 250 rig ensures that all materials are retained within the core barrel before direct extrusion into sample liners at surface.  This is idea when working with contaminated materials and ensures each working remains clean and operatives remain clear of potential contaminants.

The LS 250 rig can also be used to core through rock using either conventional or wire-line rotary drilling methods therefore offering the opportunity of capturing the entire geological column within the borehole. To maximise the benefits of sonic drilling capabilities, the LS 250 rigs are mounted on wide rubber tracks and supported by LGP Morooka vehicles.

Rotary Boreholes

Rotary drilling is used to form observation holes and facilitates the recovery of continuous representative cylinders of soil and rock. Drilling work can be undertaken in various diameters employing either open-holing, conventional, wireline (Geobore S) coring and/or Symmetrix techniques.

These can be used appropriately to characterise the geology (both soil and rock strata), highlight the presence of near-surface mineral workings in mining regions (in accordance with CMRAs) and provide design information for deep excavations such as road cuttings and tunnel construction.

Drilling can be performed using different flushing media (water, air, mist, mud etc.) and coring bits (depending on the characteristics of the material) with the recovered core either lined or unlined depending on preference.

SafeLane offers clients rotary rigs which are fully serviced and guarded in accordance with current UK health and safety legislation.

Various carrier configurations and plant capacity ensure that site access can be achieved even in difficult and soft ground surface situations with the minimum of resulting damage.

The technique can facilitate a wide range of instrumentation to be installed after completion, for example vibrating wire piezometers, inclinometers, standpipes and extensometers to name a few examples.

Cable Percussion Boreholes

Cable percussion drilling constitutes a routine site investigation technique carried out on site using 150 or 200mm casing and tools, (although the Group does additionally offer 250mm, 300mm or larger diameters for specialist requirements e.g. deep multi-layered strata conditions.)

Our in-house drilling crews are some of the most experienced in the business as they regularly drill boreholes to depths in excess of 40 metres in extremely challenging ground, where necessary using aquifer protection measures between potentially contaminated interfaces.

Rigs are generally towed into position using a 4WD vehicle or, if in soft ground conditions, low-ground pressure plant.  They require a working headroom of approximately 6.7m.

Our rigs are fully equipped for standard sampling and on-site testing requirements. Cable percussion techniques allow the facility for obtaining good quality samples (dependent on groundwater and material characteristics), and where required, boring can be extended into weak rock strata.

This relatively low-cost method of investigation provides a good basis to perform various on-site test procedures and facilitates the installation of different types of down-hole monitoring apparatus. The technique provides a good balance between cost effectiveness, technical flexibility and capability for a multitude of subsurface drilling environments.

Dynamic Probing

The primary purpose of dynamic probing is to enable geotechnical engineers to assess the sub-surface ground conditions using simple qualitative or quantitative methods (often using soil correlations and empirical relationships).

The dynamic probe process involves driving a cylindrical sacrificial or fixed cone into the ground using a high frequency percussive hammer. Blows per 100mm are recorded and after every 1m section a torque reading is recorded, a further rod is then added, and the process is continued until the probe refuses to penetrate the ground, or the test reaches the required depth.

The results are plotted on a graph which provides a visual representation of the soil penetrated versus depth and hence an in-sight into density/consistency variations.

Window Sampling Boreholes

Window sampling techniques can be effective in a range of difficult and restricted access situations. To provide enhanced flexibility to our investigation operations, SafeLane Global can call upon a wide range of small bore window sampling and probing methods.

The technique is routinely used for sampling and on-site testing of fine grained cohesive and fine to medium granular soil materials to a maximum depth of 10m (routinely 5 to 6m).

Pavement (Asphalt) and Concrete Coring

Diamond pavement and concrete coring involves taking a concrete cylinder sample from a structure or road pavement for visual assessment and testing purposes. Visual assessment and laboratory testing procedures undertaken on the core sample (or specific layers) typically assist in determining the strength/deterioration, degree of compaction, voiding, composition together with other parameters.

Asphalt can be screened using PAK marker for the presence of coal tar in the binder material, which can then be analytically quantified by specialist chemical testing.   

Restricted or Difficult Access

Where access is difficult, such as basements, confined or built-up areas, SafeLane has significant experience and access to bespoke resources from which solutions can be established suitable for most geotechnical applications and purpose.

For example, the SafeLane group offers a low headroom cable percussion rig, cantilever and mining platforms (for safe drilling over abandoned shafts) as well as a number of other unique access methods.

Low Ground Pressure

The group operates 22 items of low ground pressure plant comprising 20 Morooka and 2 Hagglund BV vehicles. A mix of rotary, cable percussive, window sampling and dual-purpose rigs can be mounted to these vehicles, dependent upon site conditions and client requirements.

Mechanical Excavated Trial Pits

When construction work is planned on an existing structure that has shallow foundations, determining the extent and the compositional properties of the foundations may be necessary.  Trial pitting can be the solution.

Mechanically excavated trial pits provide a tool for rapid assessment of widespread, shallow soil conditions up to 4 metres deep. This solution is often chosen as the investigation methodology for multi-plot housing developments.

Hand Excavated Trial Pits

Hand excavated trial pits are often used to expose existing shallow structures such as building foundations or underground utility services in order to establish their extent (e.g., thickness and depth), accurate position and, where required, to facilitate the acquisition of targeted geotechnical and/or geo-environmental samples.  

The hand excavated trial pitting approach can also be used in combination with other techniques such as diamond coring or probing to supplement their usefulness, particularly with respect to investigations undertaken within building interiors.

On-site test procedures can follow.

2b – On-Site Testing

Cone Penetration Testing

Cone penetration testing (CPT) is used to determine the geotechnical engineering properties of soils and delineating soil stratigraphy. Often used as part of an integrated ground investigation approach, CPT can provide a fast and cost-effective means of quantifying the geotechnical and geo-environmental properties of soils and for determining potential unexploded ordnance (UXO) risks.

Standard Penetration Testing (SPT)

Standard penetration testing (SPT) undertaken periodically during borehole advancement provides soil or weak rock parameter information which is routinely used for geotechnical design applications.  The results derived from SPTs can be used to determine the relative density, bearing capacity and settlement of granular soil, as well as the approximate strength of cohesive soil where appropriately applied.

Permeability Testing

Variable head, constant head and slug permeability testing (for more permeable or dynamic groundwater systems) is offered either as a component part of a larger programme of site investigation or as a standalone operation.

Soakaway (Infiltration) Testing

Site soakaway testing that conforms to BRE 365 procedures is available as a component part of our site investigations services or as a standalone operation.

Miscellaneous On-Site Testing

A full range of UKAS accredited and supporting site testing services are also available from a number of SafeLane’s UK locations.  These tests include nuclear density gauge, sand replacement and core cutter density, California Bearing Ratio (various equivalent alternatives), plate load testing (100mm to 760mm diameter), resistivity, thermal conductivity probing, hand or borehole shear vane (Geonor and Farnell) together with other standard geotechnical procedures.

2c – Geotechnical and Chemical Testing

Chemical Testing

Geo-environmental testing for the assessment of contaminated land represents a key highlight within a broad range of services offered by the SafeLane group.  Testing encompasses the analysis of soil, water, leachate, gas and building materials. 

The scope offered includes but is not limited to: asbestos, metals, cyanide & thiocyanate, sulphur, sulphide, sulphate, pH value & chloride, phenols, polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPHs), volatile and semi-volatile organic compounds (VOC & SVOC), polychlorinated biphenyls (PCBs), herbicides, ammoniacal nitrogen, total nitrate, total hardness, dissolved organic carbon, leachate preparation and analysis, waste acceptance criteria (WAC), and cement content.

Equipment utilised includes gas chromatography/mass spectroscopy, inductively coupled plasma spectroscopy, ultra violet visible spectroscopy, gas chromatography, and furnace atomic absorption spectroscopy. 

SafeLane’s Terra Tek is UKAS/Mcerts accredited and has an in-house team of experienced and fully qualified analysts.

Geotechnical Testing

SafeLane’s group of companies offer geotechnical testing facilities which can undertake large-scale laboratory driven projects.  Testing services include but are not limited to: soil classification procedures (moisture content, liquid and plastic limits, particle density, particle size distribution, maximum/minimum density), soil suitability assessment (moisture condition value, dry density/moisture content relationship and dispersibility, California Bearing Ratio, lime stabilisation), deformability (one-dimensional consolidation, swelling and collapse characteristics), permeability and strength related analysis (undrained unconsolidated triaxial, large and small shear box, effective stress (CUT, CDT))

SafeLane’s Terra Tek, Raeburn Drilling Northern and Allied Exploration and Geotechnics are all UKAS accredited and have  in-house teams of experienced and competent laboratory technicians.

Aggregate & Rock Testing

SafeLane’s UKAS accredited rock testing facilities encompass procedures such as water content, porosity and density, maximum/minimum density, particle shape – flakiness index, unconfined compressive strength, point load index, 10% fines value – dry and soaked, resistance to fragmentation – Los Angeles abrasion, aggregate impact value, particle size distribution, uniformity coefficient, magnesium soundness and slake durability.

Geotechnical & Environmental Reporting

Data acquired from site operations is processed through specialist software designed for the storage of sub-surface exploratory hole information. This allows the preparation of detailed exploratory hole records, graphs, geological cross sections, histograms and tables in formats that can be altered to suit client needs.

Our reports are detailed and accessible yet concise, ensuring the prioritisation of the clear and unambiguous presentation of  data.

A wider variety of geotechnical and environmental reporting services, including GQRAs and DQRAs for ground contamination, detailed interpretation of the ground conditions to Eurocode standards, contamination verification and site surrender reports is also available.

Laboratory, specialist chemical and all ground related data derived from the programme of investigations can be provided electronically to industry recognised AGS 4.0 standards.

Ground Water and Gas Monitoring

The SafeLane group offers an extensive range of instrumentation options and expertise for the measurement of on-site gas and water parameters in the surface and sub-surface environment.

All monitoring equipment is fully calibrated and used by experienced environmental personnel.

Automated Systems

Frequently, critical engineering applications require regular updates with respect to the subsurface regime, particularly in connection with groundwater or gas fluctuations. SafeLane Global has in-house expertise to design, install, commission and maintain automated ground information systems.

Applications may include the installation of an array of vibrating wire piezometers to continually monitor groundwater related pressure variations within and immediately below impoundment structures.

Alternatively coastal erosion (cliff stability) offers another constantly changing scenario which can be monitored using an automated solution, namely a groundwater monitoring device installed in combination with an in-place inclinometer measurement system.

Installed systems are configured to continuously monitor the in-ground regime; dataloggers may employ telemetry modules for uploading readings instantaneously to a remote server facilitating immediate access to the data. Instrumentation elements can be installed in either rotary or cable percussive exploratory holes in order to target specific points in the sequence whilst using bespoke methods of monitoring device insertion and sand pocket formation.

Solutions use programmable acquisition equipment units to receive raw data from the in-ground sensors at the desired intervals. Datalogger units can be installed in purpose-built manhole chambers with trenched and ducted cabling so that instruments can be grouped in one place for convenience.

3 – Deliver the Project

SafeLane Global offers three main service umbrellas to help you, the client, deliver your project: water wells & geothermal, site remediation, and quality control assessment.

3a – Water Wells & Geothermal

Water Wells

Private water wells are drilled for commercial and residential clients alike.  Heavy water using manufacturing businesses, farms and parks or commercial drinks makers can all save money with a private supply.  Equally, residential homes that are off the grid, want to be off grid or want a more reliable, cleaner, and cheaper supply can have a water well drilled on their property.

Open Loop Heat Exchange Boreholes

To harness the geothermal energy in below ground aquifers, two or more boreholes can be drilled and an open loop ground source heating scheme installed.  The abstraction borehole draws water from the aquifer, it is carried to a heat pump, where, by means of an evaporator, heat is transferred from the water. That water is then re-injected via the discharge boreholes.

Open-loop systems are regulated by environmental agencies because they alter their energy source by the extraction of water from the aquifer, that could, in turn, affect the characteristics of the ground and, eventually, result in the desiccation of the aquifer.

Closed Loop Heat Exchange Drilling

A closed loop heat exchange system absorbs naturally occurring heat contained within the ground and releases it to heat a building.  The system combines a heat pump that draws water and antifreeze solution through an underground loop (water pipes), buried at shallow depths.  It provides warmth in a renewable way, requiring little maintenance. 

There are three different types of closed loop system – horizontal, vertical and a pond or lake system.  Drilling requirements depend on the solution chosen.  As closed-loop systems are limited to exchanging heat with the ground (or groundwater), they do not alter the environment and are therefore no subject to environment agency regulation.

Pumps & Water Treatment

SafeLane Global’s colleagues at WB+AD Morgan can check your borehole is outputting safe water by performing UKAS accredited chemical and bacteriological analyses. 

Based on the test results, WB+AD Morgan can provide you with a range of water treatment solutions, including water filtration and purification – ensuring your water is clean, safe to drink, and soft. 

WB+AD Morgan will install, test, and maintain the solutions for you – meaning you do not have to worry about your water ever again.

3b – Site Remediation

Remediation Services

Underground services may be an obstruction to or cause interruptions to your site, especially when they are not mapped and their locations are not obvious.  Thankfully, SafeLane can survey, mark, and clear any buried apparatus by utilising a specialist ground penetrating radar (GPR).  SafeLane can also remove said utilities via vacuum extraction if needs be.

Utilities Services Clearance

Underground services may be an obstruction to or cause interruptions to your site, especially when they are not mapped and their locations are not obvious.  Thankfully, SafeLane can survey, mark, and clear any buried apparatus by utilising a specialist ground penetrating radar (GPR).  It can remove said utilities via vacuum extraction if needs be.

Topographical Surveys

SafeLane can also provide topographical surveys, accurately documenting the natural and manmade features across your site, with precise locational, spatial and elevational information.

3c – Quality Control & Assessment

Continued Professional Development (CPD) Training

SafeLane Global offers CPD accredited UXO safety briefings and counter-improvised explosive device (C-IED) safety training.  UXO safety briefings are primarily conducted for construction workers, those conducting intrusive works, and emergency first responders.

It covers the types of UXO that contaminate land in the UK, ordnance identification, safety precautions, how to respond to suspicious objects, and management review safety planning.  The C-IED safety training is designed by IEDD and EOD experts to counter potential terror threads in the UK.

Contact Us

For more information regarding any of our turnkey site investigation solutions, contact SafeLane Global today via / +44 (0) 1634 471 340.

Alternatively, contact any of SafeLane’s business units to learn more:

DTS Raeburn –

Raeburn Drilling –

Raeburn Drilling Northern –

WB+AD Morgan –

Allied Exploration & Geotechnics –

Terra Tek –

SafeLane UK Land Map


Case studies

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View case studies

Contact us today

SafeLane Global has been operation for over 30 years and has completed over 30,000 projects. It is now an expert in site investigation solutions. Contact us today to learn how we can help you.

Contact Us