The map shows the risk of potential pollutants and nutrients leaching through the soil to ground and surface waters. This map primarily covers the cultivated land in Scotland. The soil leaching potential gives information on the likelihood of a potential pollutant that is applied to the soil surface infiltrating the soil and leaching to a water course or ground water in three main categories (High, Intermediate and Low) with the High class being subdivided into 3 classes while the intermediate class is subdivided into 2 classes. Note: soils over current and restored mineral workings and in urban areas that are often disturbed or absent are assumed to have little ability to retain potential pollutants and so are classified as having a high leaching potential (see Lewis, M.A., Lilly, A and J.S. Bell. 2000. Groundwater vulnerability mapping in Scotland: Modifications to classification used in England and Wales. In: Groundwater in the Celtic Regions: Studies in Hard Rock and Quaternary Hydrogeology. Eds. N.S. Robins and B.D.R. Misstear Geological Society Special Publication No. 182. pp 71-79.).
