Risk Assessment and Ground Investigation

Overview

The context of the problem and the objectives of the process must be clearly identified at the outset of the risk management process. Risk assessment is essential in managing of the risks from land contamination and in the context of both the Part IIA EPA 1990 regulatory regime and planning policy.

A three tier approach is taken to risk assessment:

• Preliminary risk assessment
• Generic quantitative risk assessment
• Detailed quantitative risk assessment

Once the need for risk assessment has been identified, it is necessary to carry out a preliminary to determine whether a generic or detailed quantitative risk assessment is required, or both.

Developing the conceptual model is the principal function of preliminary risk assessment and is an important thread throughout the process as it supports the identification and assessment of pollutant linkages.  The model is subsequently refined or revised as more information and understanding is obtained.

The overall process is iterative in practice. A more detailed assessment may raise issues that require the earlier tiers to be revisited. The process within each tier may also be iterative.

Each tier of risk assessment requires decisions to be made on the basis of information about the site:

• The type, extent, location and behaviour of potential contaminants
• Physical conditions on or around the site
• The characteristics of the people and the environment potentially affected by contaminants on the site

Information used in risk assessment may also be essential in informing decisions about possible solutions for managing the risk. It is therefore essential to ensure that the appropriate range and level of information is collected at each tier of risk assessment and that this information meets appropriate quality criteria.

The risk assessment process needs to take into account the degree of confidence required in decisions.  Correspondingly, the identification of uncertainties is an essential step in risk assessment. Some uncertainties can then be reduced e.g. by obtaining better data or refining models to improve their validity.

Temple can design, manage and report on all types of brownfield risk assessment and corresponding site investigation works.

Service Definition

Temple adopts best practice in all projects we undertake and adhere strictly to the model procedures for the management of land contamination recently published by Defra and the Environment Agency. We provide a ‘one-stop shop’ service including integral safety checks as part of any intrusive site investigations. Alternatively, we can provide ad-hoc support such as peer review or interim project management support as necessary.

We also offer institutional support where we provide training and support over the short, medium or long term to build in-house capacity.

A mixture of intrusive and geophysical techniques is available to ground investigation practitioners. Generally boreholes and trial pits are dug by excavators. The site supervisor can then make observations regarding the nature and characteristics of the soil and indicate the presence of specific contaminant. Soil and water samples are collected at the same time. Several tests can be carried out in the field, but it is usual for samples to be sent to commercial laboratories (NAMAS accredited) for detailed analysis.  While these tests are carried out, a factual on-site ground investigation report is prepared.  When laboratory results are received a risk assessment is undertaken.

Service Users

Temple Regeneration provides risk assessment and ground investigation services to land owners, developers, contractors, banks, local authorities and government agencies.

Triggers

Risk assessment and site investigation normally takes place:

• during land transactions
• prior to construction works
• as part of schemes to manage environmental liabilities
• following pollution incidents
• by local authorities carrying out scheduled inspections.

Charging Structure

Temple’s rates are very competitive and we can offer this service either on a fixed price or a time and expenses basis with budget ceilings.  Fees for similar work have varied from £5,000 to over £250,000 depending on the scale of the project.

Contacts

If you have any questions about our services please contact us on 0207 394 3700 or enquiries@templegroup.co.uk

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