This layer includes information about surficial deposits at 1:500,000 scale used in preparing the GCSM for Wisconsin. Surficial deposits are defined as the unconsolidated materials above the bedrock. Because the NsoilsN layer used in the GCSM includes only the material in the first 5 feet below the land surface, the surficial deposits layer is intended to account for the unconsolidated material between the soil and the top of the bedrock. The texture and permeability of the surficial deposits affect the rate at which infiltrating water will reach the water table. In Wisconsin, these surficial deposits are often the most important factor in determining groundwater contamination susceptibility.