A Groundwater Protection Scheme provides guidelines for the planning and licensing authorities in carrying out their functions, and a framework to assist in decision-making on the location, nature and control of developments and activities in order to protect groundwater. Use of a scheme will help to ensure that within the planning and licensing processes due regard is taken of the need to maintain the beneficial use of groundwater.
Groundwater Protection Schemes are county-based projects that are undertaken jointly between the GSI and the respective Local Authority.
The groundwater protection scheme comprises two components:
- A land surface zoning map (or maps) called the groundwater protection zone map, and
- Groundwater protection responses for existing and new potentially polluting activities.
The role of the GSI is in the production of the land surface zoning map, whereas decisions on groundwater protection responses are the responsibility of the statutory authorities.
The risk to groundwater is defined through assessments of Groundwater Vulnerability
, Aquifer potential
, and Source Protection Areas. Datasets of vulnerability, aquifer potential, and source protection areas are generated by the GSI using field mapping in combination with readily available existing information and a limited amount of targeted drilling and testing. The vulnerability and aquifer datasets cover the entire land surface of a given area, while the source protection area datasets are specific to the catchments of selected groundwater supply sources. The three datasets are merged to produce Groundwater Protection Zones. Each zone is represented by a code (e.g. Rf/H), which enables an assessment of the risk to groundwater, independent of any particular hazard or contaminant type. This assessment should be regarded as a guide in evaluating the likely suitability of an area for a proposed activity prior to site investigations.
Once the groundwater protection zone is defined for an area, the hazards posed by selected human activities can be evaluated to assess the appropriate risk management measures, or Groundwater Protection Responses, for these activities. The Groundwater Protection Responses, which are shown by a code (e.g. R2¹), indicate the likely degree of acceptability of each activity in that Groundwater Protection Zone. The full explanatory text for these response codes describes the investigations and planning or licensing conditions that may be necessary in order to make a balanced, pragmatic, scientifically defensible decision. Currently available codes cover:
- IPC Landspreading,
- On-site wastewater treatment systems (e.g. septic tanks),
- Out wintering pads, and
- Earth-lined slurry stores.
Further details are available from the Groundwater Protection Schemes report
published by the Department of the Environment and Local Government, Environmental Protection Agency and Geological Survey of Ireland.