Sub Surface provide Site Investigation services to satisfy our Clients’ requirements along with, where necessary, the various regulatory requirements of Planning Departments, Environmental Health Departments, the Environment Agency, Building Control departments and property transactions.
A Site Investigation is field and laboratory work to assess the ground conditions within the geographical, geological, hydrogeological and environmental context. Site Investigations are tailored to determine the ground conditions for foundations, piling, vibroflotation, slope stability, retaining walls, earthworks, road design, sewer construction, dewatering, tunnelling, Phase 2 investigations for contamination analysis, landfill gas assessment, waste classification and waste disposal, etc.
Our Site Investigations comprise of obtaining disturbed and undisturbed samples and carrying out in-situ testing (SPTs, CPTs) to characterise the ground conditions sufficiently. This allows safe and economic designs to be developed and reduce, as far as possible, the occurrence and impact of unforeseen ground conditions.
All our Site Investigations are carried out in accordance with the UK Specification for Ground Investigation, Second Edition, British Standard Codes of Practice BS5930 and British and European Standards BS EN 1997-2 (EC7). For Quality Assurance, all our drillers have an NVQ in Land Drilling from the British Drilling Association and we are accredited by Constructionline and CHAS.
Site Investigation Intrusive Techniques
Our Contact Managers at Sub Surface will advise on the most suitable intrusive techniques for your site depending on the site location, proposed development, anticipated geology, Client requirements, any Local Authority requirements and when available, the findings of a Desktop Study. A Site Investigation may include:
- Cable Percussive Boreholes – Most commonly used
- Window Sampling (Mini Boreholes) – Small scale for shallow foundations only
- Rotary Drilling – Rotary Core Drilling and Rotary Open Hole Drilling
- Dynamic Probing – Site profiling
- Trial Pits – Machine excavated, Hand dug and Foundation Pits
Our Geotechnical and Geo-Environmental Engineers will subsequently log the samples in accordance with BS EN ISO 14688-1 and BS EN ISO 14689-1.
Pre Site Surveys
Prior to any Site Investigation, if required, we offer a range of surveying options, including:
- CAT Scan
- Underground Utility Plans Search
- Topographic Survey
- Ground Penetrating Radar (GPR) Survey
- Preliminary Unexploded Ordnance (UXO) Risk Assessment
- UXO Risk Assessment
- Ecological Survey
- Archaeological Survey
Post Site Investigation – Testing and Reporting
Our Geotechnical and Geo-Environmental Engineers will design a site specific Geotechnical Laboratory Testing and Contamination Testing schedule to be undertaken within our in-house soils laboratory or external UKAS and MCERTS chemical laboratory.
Our Site Investigation, testing and monitoring results can be incorporate into an Interpretive Report, written by one our experienced professionally qualified Geotechnical and Geo-Environmental Engineers and can include:
- Foundation Design – (strips and pads, piled, vibroflotation, trench fill, semi-raft and raft foundations, including shrinkage and swelling of clays, concrete classification and they are often integrated with contamination analysis and gas monitoring, where required)
- Ground Stability due to Mining
- Underground Cavities, Gypsum and Chalk Dissolution Features
- Slope Stability Analysis
- Retaining Walls and Basements
- Contamination Analysis
- Waste Disposal
- Landfill (Ground) Gas Risk Assessment
Whom to Contact
If you would like a quote for a Site Investigation or have any questions, please do not hesitate to contact your Regional Sub Surface Office.