The Map’s foundation lies in the assessment of soil functions, as depicted in Environmental Atlas Maps 01.12.1 through 01.12.5 . Additionally, it draws on the Soil Associations Map 01.01 which identifies soil associations at risk of material contamination, such as those characterised by war debris, sewage farms, and railway tracks.
Data from Map (Impervious Soil Coverage) of the Environmental Atlas Map 01.02 of the Environmental Atlas, which includes track gravel as impervious, was consulted to represent impervious soil coverage classes.