Contaminated Land Investigation

Contaminated Land Investigation

There has been an increase in legislation governing contaminated land and groundwater in recent years.  This,  coupled with increasing pressure to redevelop brownfield sites has resulted in a much greater need to characterise soils and groundwater both physically and in terms of possible contamination. Our team has a long history of such studies and is able to carry out routine borehole monitoring studies as well as using specialist machinery such as the Geoprobe for more complex site investigations. We have completed a broad range of projects from assessment of domestic properties for developers to the investigation of contamination in creeks and estuaries, and intrusive sampling over large areas of heavily contaminated industrial sites for clients including chemical, oil and mining companies. Phase I Contaminated Land Assessment Phase II (Intrusive) Contaminated Land Assessment Surface and Groundwater Monitoring Intrusive Investigations using the Geoprobe Recent Projects...
Phase I Contaminated Land Assessment

Phase I Contaminated Land Assessment

A Phase I contaminated land assessment consists of a desk based study followed by a site walkover survey. Phase I investigations are carried out in accordance with the Environment Agency CLR11 guidelines and relevant BSI standards. Environmental Regulators recommend the assessment of potential pollutant linkages and associated risks through the concept of the source, pathway, receptor model. A source, pathway and receptor must be present and consequent linkage must be established in order to determine the requirement and scope of any future geo-environmental investigation. A Phase I contaminated ground assessment includes both historical and present uses, allowing the forming of a conceptual model for the site with regard to its geology and environmental sensitivity. In many cases the Phase I contaminated land survey will not result in the identification of any significant risks and will provide sufficient information for planning consent. However, where the conceptual model identifies areas of high risk that cannot be mitigated, or further information is required (e.g. if soil or groundwater contamination is suspected) this will be highlighted and will form the scope of the Phase II investigation. Where this occurs, Ecospan Environmental has the specialist equipment and expertise to complete the secondary intrusive investigations required for further characterisation of site contamination. Recent...
Phase II (Intrusive) Contaminated Land Investigation

Phase II (Intrusive) Contaminated Land Investigation

A Phase II contaminated land assessment is required where the conceptual model developed during Phase I identifies areas of high risk that cannot be mitigated, or where further information is required (i.e. where a risk of soil or groundwater contamination exists). These investigations involve intrusive sampling of the soil and groundwater and sometimes soil gas. The purpose of a Phase II assessment is to determine whether any contamination exists and, if so, what the extent and level of contamination is. This information is then used to refine the conceptual model and risk assessment. The risks arising from the contaminants present on the site are assessed for all potential pathways of exposure to determine whether they are acceptable. This is commonly achieved using soil guideline values (SGVs) or by using the Environment Agency’s CLEA model. In instances where the risks cannot be adequately mitigated and are considered unacceptable, remediation will be required prior to development. Ecospan Environmental Ltd usually undertakes intrusive sampling of contaminated land and in situ groundwater or soil gas using the Geoprobe. Recent...
Intrusive Investigations using the Geoprobe

Intrusive Investigations using the Geoprobe

Intrusive Investigations using the Geoprobe The geoprobe is mounted on a small self-propelled tracked vehicle making the system highly mobile, capable of sampling in most terrains down to a depth of 25 meters. It can sample groundwater, soil and soil-gas in all granular and cohesive soils and will penetrate tarmac and concrete with ease. The main advantages of geoprobe sampling include: Rapid deployment and sampling times. Minimal physical and chemical disturbance of the sample giving a high degree of sample integrity and excellent data quality. Containment of soil samples within a clear liner enabling areas of contamination to be recorded visually. Minimal disruption of surfaces as the small 50 mm hole produces little spoil and can easily be backfilled. Only 10% of the volume of a traditional borehole needs to be purged on each sampling occasion.  Applications The Geoprobe is the ideal tool for: Initial rapid investigations and screens Installation of monitoring wells up to 15m. Groundwater monitoring and profiling Contaminant plume mapping Determining the optimum location for permanent monitoring wells Sampling in areas containing significant amounts of underground debris Sampling inside warehouses, production builds and other confined spaces Recent Projects...
Surface and Groundwater Monitoring

Surface and Groundwater Monitoring

Surface and Groundwater Monitoring Contamination on sites with an industrial history can impact on a number of environmental receptors including groundwater. For this reason many sites are required to routinely monitor a network of boreholes and surface waters. Ecospan have worked on a large number of highly contaminated sites throughout Europe. Our experience, therefore, ensures that we are intimately familiar with working on large manufacturing sites and with the working procedures that exist on them. Applications Monitoring of existing contaminants for regulatory compliance (e.g. Environmental Permitting) Providing information on the distribution and/or movement of contaminants Determining the efficacy of remediation projects Measuring the levels of groundwater derived contaminants in surface waters to ensure that relevant limits (e.g. EQS) are not exceeded Monitoring of landfill sites Lagoon and pond sampling (See Water and Sediment Sampling and Profiling). Sampling Procedures All sampling is undertaken in accordance with standard operating procedures based on regulatory guidelines or internationally recognised methods (e.g. ASTM). This ensures that the samples are representative of the groundwater and eliminates cross contamination. Depending on the nature of the contaminants of interest and site specific features, sampling may be undertaken using a wide range of techniques such as: inertial pumps, peristaltic pumps, bladder pumps, centrifugal pumps and bailers. Correct sample preservation and storage is specific to the nature of the likely contaminants and critical in measuring their levels in the water. For this reason protocols are developed in liaison with the analysing laboratory. Chemical Analysis All analysis is undertaken by MCERT accredited laboratories and in accordance with accredited methods to ensure compliance with regulatory quality standards. Recent...