Groundwater Vulnerability 1:40,000 Ireland (ROI) ITM

The Groundwater vulnerability concept is based largely on the question “can water and Contaminants move in the subsurface materials (soil and subsoil) and/get down to Groundwater easily?” Groundwater is most at risk where the subsoils are absent or thin and in areas of karstic limestone, where surface streams sink underground at swallow holes. Groundwater vulnerability maps are based on the type and thicknesses of subsoils (sands, gravels, glacial tills (or boulder clays), Peat, lake and alluvial silts and clays) and the presence of Karst features. Groundwater that readily and quickly receives water (and Contaminants) from the land surface is considered to be more vulnerable than Groundwater that receives water (and Contaminants) more slowly and consequently in lower quantities. Groundwater vulnerability is classified as follows: Rock near surface or Karst (X) Extreme (E) High (H) Moderate (M) Low (L). Scale: 1:40,000 These data sources are used to Classify Groundwater vulnerability: Subsoil Permeability; Depth to Bedrock; Groundwater Karst DataSinking Teagasc streams subsoils The Groundwater Vulnerability map along with the aquifer maps and Source Protection Area maps are merged to produce Groundwater Protection Zones. Each zone enables an assessment of the risk to Groundwater, independent of any particular hazard or contaminant type. The Groundwater Protection Zones form one of two components of Groundwater Protection Schemes. 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 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 volatile 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.地下水脆弱性（Groundwater vulnerability）的核心概念很大程度上围绕这一问题展开："水与污染物能否在地下介质（土壤与亚土层）中运移，并轻易抵达地下水层？" 当亚土层缺失或厚度极薄，以及喀斯特石灰岩区域（地表溪流在落水洞处汇入地下）中，地下水面临的风险最高。地下水脆弱性图的编制依据为亚土层的类型与厚度（包括砂、砾石、冰碛物（glacial tills，或称漂砾黏土（boulder clays））、泥炭（Peat）、湖相及冲积粉土与黏土），以及喀斯特（Karst）地貌的发育情况。 相较于接收地表水（及污染物）速率缓慢、补给量较低的地下水，能够快速、便捷地接收地表输入的水与污染物的地下水，其脆弱性更高。 地下水脆弱性等级划分如下：近地表岩土或喀斯特（X）、极高（E）、高（H）、中（M）、低（L）。制图比例尺为1:40000。 用于地下水脆弱性分级的数据源包括：亚土层渗透性（Subsoil Permeability）、基岩埋深（Depth to Bedrock）、地下水喀斯特数据、Teagasc落水溪流数据以及亚土层数据。 地下水脆弱性图与含水层图、水源保护区（Source Protection Area）图进行叠加合并，即可生成地下水保护区。每个保护区均可独立于特定灾害或污染物类型，开展地下水风险评估。 地下水保护区是地下水保护方案的两大组成部分之一。 地下水保护方案可为规划与许可主管部门履行职能提供指导，并为各类开发与活动的选址、性质界定与管控决策提供框架，以实现地下水保护。该方案的实施，有助于确保在规划与许可流程中，充分考量维持地下水有益用途的必要性。 地下水保护方案为以郡为单位的项目，由GSI与对应地方主管部门联合实施。 地下水保护方案包含两项核心内容：一是地表分区图（可多幅），即地下水保护区图；二是针对现有及新增潜在高风险活动的地下水保护应对举措。 GSI负责地表分区图的编制工作，而地下水保护应对举措的决策则由法定主管部门负责。