The Environment Agency has duties and powers to ensure the protection of groundwater and the remediation of contaminated land and groundwater. These responsibilities are covered by the Groundwater Regulations 1998, Water Resources Act 1991 (WRA 1991) and the Environmental Protection Act 1990 (EPA 1990). To assist in this regulatory role, environmental risk assessment methodologies are employed by the Agency as part of the decision-making process. With regard to the protection and remediation of groundwater, contaminant fate and transport models are often used. They may take the form of deterministic models or probabilistic tools, such as LandSim and ConSim.