Contaminated land - a discussion of risk, standards and 'trigger values'

Following concern over groundwater and land pollution, with its consequent environmental and human health hazards, from chemical waste sites, the author argues for a risk-based approach to site assessment and prioritization. This would also help in deciding which environmental benefit might arise from various pollution correction measures. Such assessment must be based on knowledge of the chemical nature and quantity of the pollutants and their point of entry into the environment, the routes they take and their final target. This Source-Pathway-Receptor/Target approach is explained as is the concept of ''trigger values'' of a substance, which, if exceeded, carry a risk of pollution occurring. (UK)