Contaminated Land
Site Assessment and Remediation
Site Audits



Site Assessment and Remediation

Environmental Site Assessments
Environmental Site Assessments (ESA) involve the evaluation of the status of land with respect to environmental contamination - in particular, chemical contamination of soil and groundwater. The scope of an ESA may also extend to the assessment of the potential impact of contaminant migration from the investigated area to adjacent areas, surface water and groundwater resources.

When is an ESA required?
ESAs are often commissioned:

  • as pre-acquisition or pre-sale assessments, on behalf of either purchaser or vendor, when a property is being sold; such assessments can be considered analogous to the Title and Planning searches normally carried out as part of the conveyancing process;
  • as pre-development assessments, when a property is to be redeveloped or is to have its usage changed - for example, from a factory to a residential subdivision;
  • as pre-development assessments of greenfield sites, to establish baseline conditions and assess environmental, geological and hydrological constraints to development; an example would be an assessment of waste disposal constraints on rural subdivisions;
  • as audits of the environmental effects of an ongoing operation, to ensure sound environmental practice and regulatory compliance.

Who may require an ESA?
The potential liabilities associated with the purchase of land which may be contaminated are such that many aware organisations, including lending institutions, banks and finance houses (particularly those who have previously been exposed to environmental liability), are themselves commissioning or requiring loan clients to commission, environmental assessments for all major land purchases. In other cases, environmental assessments are required by planning authorities (generally local councils) prior to consideration of applications for rezoning or redevelopment of land to a more sensitive land use: an example of such a situation could be a developer intending to convert former industrial land into residential properties.

In fact, the financial risks associated with the purchase of contaminated land are such that no one should undertake any land purchase without considering the possibility that the site may be contaminated. As vendors may be liable for misleading statements made to potential purchasers, and owners or lenders may be liable for the activities of occupiers, anyone associated with land transactions should consider the benefits of an Environmental Site Assessment carried out by a specialist. Although the financial risks associated with land contamination cannot be eliminated, they can be managed, and one of the best management tools available is the Environmental Site Assessment.

What is involved in an ESA?
We prefer to undertake ESAs as staged studies, comprising up to three stages.

Stage 1 typically involves a desk review of site conditions, including -
  • assessment of available topographical and geological mapping, current and historical aerial photographs;
  • review of relevant published geological, geotechnical and hydrogeological information;
  • compilation of the sites ownership history, and the nature of activities undertaken on the site by its previous owners;
  • interviewing the current and, where possible, previous owners and occupiers of the site, to assess environmental management practices, and the location of particular activities on the site;
  • review of the sites development and regulatory history, with particular attention to development applications, discharge licences, compliance notices and orders imposed under the Environmentally Hazardous Chemicals, Unhealthy Building Land and Contaminated Land Management Acts;
  • assessment of the status of adjacent land, and its potential impact on the site.
  • a site reconnaissance comprising a walk-over and visual observations by an experienced assessor, supplemented with photography and on-site instrumental measurements.

Stage 2 investigations are only carried out if warranted by the results of Stage 1. These investigations involve sampling and analysis of materials from the site in order to establish levels of contamination. The number of samples, their location, depths and recommended analytical suites will be strongly influenced by the results of the previous Stage 1 investigations.

The final stage of the assessment process involves the preparation of a full remedial action plan for site clean-up. That plan must then be implemented under appropriate supervision, and validation sampling carried to to demonstrate that remediation has been effective.

CMJA believes that this staged approach to environmental site assessments enables us to do a better job – by keeping our clients informed at each stage of the ESA, and by providing them with an assessment completed to high technical standards. We also believe it offers our clients a service that is better value for money.

Who should undertake your ESA?
Your ESA should be undertaken by a consultant who is both skilled and experienced in this very specialised area, who understands the risks involved, and who is able to clearly communicate his results to you.

© C. M. Jewell & Associates Pty Ltd - 1/13 Kalinda Road, Bullaburra, NSW, 2784. PO Box 10, Wentworth Falls, NSW, 2782.
Ph (02) 4759 3251. Fax (02) 4759 3257.