Site Investigation

Earth Environmental & Geotechnical provides an extensive range of Site Investigation Services for clients to inform construction designs and satisfy conditions for planning applications, building control departments, The Environment Agency. Subsurface site investigations are conducted to establish ground conditions and composition of the ground beneath a development site before construction starts.

Trial Pits

Trial Pits

Trial Pits are used for sub-surface site investigations and examination of the soil, rocks and groundwater. Trial pits ideally proceed construction works to determine the geology and the water table of that specific site and are typically between 1 and 4 metres deep.

What is Rotary Drilling

Rotary Drilling

Rotary drilling is used to collect soil and rock strata samples, or to form deep observation boreholes. Rotary drilling is used for very dense soils and rock to investigate and analyse the sub-surface ground conditions up to a depth of 100m.

Cable Rig used for site investigation

Cable Percussion Boreholes

Cable percussion boreholes can be used to investigate the soil profile to a depth of up to 50m. Different cutting head heads are used for different soil types. Chisel for rock and hard layers, a shell for granular soils and a clay cutter for softer cohesive soils.

Windowless sampling

Window Sampling

Window Sampling is used on soft ground and cohesive strata to extract soil, clay or sand samples for geotechnical or chemical analysis. Window sampling is a great technique to recover undisturbed samples for geotechnical and environmental analysis.

Site Investigation Services

Subsurface Site Investigations are required to get a full understanding of what you are building on. The first stage in the process is the Phase 1 Desk Study. The results of the phase 1 Desk study combined with the Preliminary Development Design Proposal will inform what Site  Investigations are required next.

Site Investigation services include subsurface exploration and laboratory analysis to establish ground conditions for development sites.  These Site Investigation techniques include trial pits, rotary drilling, and window & windowless sampling and cable percussive boreholes

Any site investigation should ideally follow the development of a site walkover survey and desk-based study (Phase I Desk Study) using readily available publically archived information (historical, environmental, mining etc) that allows for a cost effective strategy to be implemented. The defined scope of work within any preliminary investigation is paramount for a successful project to be completed, the old adage “you pay for a site investigation whether you have one or not”, is commonly quoted to clients!

All site investigations are conducted in accordance with strict and well-defined health and safety practices with site-specific method statements and risk assessments provided. Prior to commencement on-site service (gas sewers, electricity etc.) information is acquired from the client (or its agents) with utility tracing conducted, if required.

Many site investigations are conducted to discharge planning conditions and our staff always ensure, time permitting, that prior to delivery of a costed proposal an outline of the proposed works are initially discussed with the regulatory authorities.

Our staff have extensive experience in the design of geotechnical, mining, and environmental site investigations in accordance with current best technical practices and planning guidance.

The site investigation services required will depend on the specifics of the site being developed including the known, strata of the area, if the site is in a coal mining area, the groundwater conditions, and potential contaminants. The known ground conditions will determine what Site Investigation techniques are most appropriate for the specific site and the proposed development. The term ‘ground conditions’ generally refers to the geology, hydrology, soil condition and any contamination of the ground on the site of a construction project. Ground conditions may be naturally occurring, man-made, or, frequently a combination of the two.

In-house drilling rigs are wherever possible used for drilling work, with approved quality sub-contractors used for projects (where necessary).

Examples of sites we have investigated are:

  • Fuel Retailing Facilities as part of portfolio divestment strategies and planned re-development.
  • Unlicenced tips with ground gas and contamination issues
  • Victorian housing estates
  • Breweries and alcohol distillery facilities
  • Cotton mills with gasometers and infilled reservoirs
  • Infilled canal sites with contaminated sediments
  • Bleach works
  • Ship building yards
  • Bulk fuel depots and blending facilities with oil spills and offsite impacts.
  • Greenfield sites with poor ground conditions associated with compressible soils and settlement issues.  Former animal burial sites and fuel storage facilities within agricultural holdings.
  • Former colliery sites with mine shafts, bell pits, adits and shallow pillar and stall workings beneath proposed development.
  • Railway cuttings and embankments with slopes stability issues associated with relict geological slip surfaces and impacted by vegetation together with nearby construction activities.
  • Landfill sites for assessment of hydrogeological risk assessment, gas migration studies, installation of monitoring boreholes, evaluation of settlement characteristic’s for surface structures on waste mass, design of earthworks and use of lining materials.
  • Quarries as part of reserve assessment, hydrogeological and slope stability assessments.
  • Foundries where tipping and waste handling practices have posed soil, ground gas and ground gas contaminations issues to wider environment and proposed end use.
  • Scrap yards with deleterious materials, PCB, oil, asbestos and metal contamination.
  • Tannery sites with potential pathogens, asbestos, metals, sludges and heavily impacted drainage system.
  • Gas manufacturing works site with a wide range of contamination issues associated with former gas production.
  • Ministry of Defence facilities including bases, airfields and weapons manufacturing complexes.
  • Existing and proposed Cemeteries for assessment of risk posed to environment including hydrogeological assessment.
  • Council owned allotments with legacy of contamination associated with ash based soil conditioner and hydrocarbon spillages.
  • Chemical works including agrochemical plants, aniline works, tar distilleries, battery works.
  • Sewage works where historic practices have resulted in sewage sludges being deposited on site

Earth Environmental & Geotechnical conduct site investigations in accordance with Eurocodes that were introduced into UK design on 31 March 2010 and has invested in equipment and methodologies demanded by the standards. We however believe that high quality site investigations arise as a result of the design, supervision, monitoring and interpretation process rather than the field equipment used.

Site Investigation Service

Site Investigation

Subsurface site investigations are routinely conducted as part of the assessment of the GeoEnvironmental status of a site including any landfill/ground gas issues, soil/groundwater contamination, assessment of mineworkings, hydrogeology, slope stability assessment or to examine geotechnical conditions for a new structure or landform.

Trial Pits

Site investigations are commonly required for the following scenarios;

  • Site Pre-Purchase Due Diligence Studies
  • Slope Stability Assessments
  • Contaminated Land Assessment
  • Foundation Design
  • Subsidence Surveys
  • PartIIa Investigation
  • Environmental Monitoring
  • Insurance Claims
  • Asset Surveys
  • Mining Survey
  • Relict foundation and obstruction assessment
  • Ground Improvement Design
  • Remediation Design and Validation
  • Asbestos Soil Risk Assessment
  • Environmental Management Audit
site investigation using Modular windowless sampling drilling rig
First day of large site investigation on part of former Darwen Paper Mill