Skip to main content.
Enviropaedia Sponsors and Supporters

Contaminated Land

( Article Type: Explanation )

The term contaminated land refers to a wide range of possible conditions where a piece of land or property contains substances that are potentially hazardous to human health or the environment. The contaminating substances may pose a physical, chemical, biological or radiological hazard. The notion of ‘pollution’ in the context of contaminated land is generally used to indicate a situation where land is sufficiently contaminated such that it poses a demonstrable risk to human health or the environment, and so the land would be described as polluted.
The investigation of potentially contaminated land is essentially a forensic process that is undertaken in a series of phased steps through which a picture of the extent of the problem is built up. Internationally there is a standard approach to each phase of investigation that is followed that represents best practice and this is similarly followed in South Africa, although there are varying degrees of rigor applied by different specialists. Initial assessment of an issue involves review of historic aerial photographs, interviews with site staff and site inspections. If a potential contamination impact is identified from this initial phase, then a Site Characterisation or Phase II investigation is undertaken.
The purpose of a Phase II investigation is to quantify through sampling and analysis the actual magnitude of the problem. From this the need for a health risk assessment and clean-up or remediation of the impact can be established. In South Africa, the most significant contamination impacts are from mining and industrial operations, in particular from abandoned or discontinued operations where there has been inadequate or no remediation on closure.
In addition to representing a major legacy liability, ongoing generation and seepage of impacted groundwater from these mines in the form of acid mine drainage is an issue which increasingly cannot be ignored despite the serious technical and financial constraints to adequately remedy the problem. Regulation of contaminated land issues in South Africa has historically been very poor.
However, regulations issued under the National Environmental Management Act (NEMA) of 1998 now include decommissioning of industrial property and remediation as listed activities that must be authorised.
Furthermore, the more recently promulgated National Environmental Management: Waste Act 59 of 2008 includes a chapter (Chapter 8) that clearly defines roles and obligations for the management of contaminated land. Draft norms and standards for investigation, assessment and reporting on contaminated land issues were developed in 2010 and are in the process of being promulgated, following which Chapter 8 of the Waste Act will be legally enforceable.