User guide : Groundwater Vulnerability (Scotland) GIS dataset. Version 2

This report describes a revised version (Version 2) of the groundwater vulnerability (Scotland) digital dataset produced by the British Geological Survey (BGS). Version 1 of the dataset was produced in 2004 by the British Geological Survey (BGS) and the Macaulay Institute (now the James Hutton Institute) on behalf of the Scottish Environment Protection Agency (SEPA), funded by the Scotland and Northern Ireland Forum for Environmental Research (SNIFFER). Version 2 uses updated input data and a slightly modified methodology. The map shows the relative vulnerability of groundwater to contamination across Scotland. Groundwater vulnerability is the tendency and likelihood for general contaminants to move vertically through the unsaturated zone and reach the water table after introduction at the ground surface. On this map, groundwater vulnerability is described by one of five relative classes ranging from 1 (lowest vulnerability) to 5 (highest vulnerability). The groundwater vulnerability map is a screening tool that can be used to show the relative threat to groundwater quality from contamination across Scotland. It can provide guidance on the vulnerability of groundwater at a regional scale, highlighting areas at comparatively higher risk of groundwater contamination, and can help indicate the degree of specific site investigation required for a new development or activity. It is designed to be used at a scale of 1:100,000 and should be regarded as a tool to aid groundwater risk assessment rather than a complete solution