Stable rock 2. Type ‘A’ soil (Clay, Silty Clay, Clay Loam, Cemented Soils and Hardpan, etc). 3. Type ‘B’ soil (Granular, cohesionless soil, like crushed rock, silt, silt loam, etc). 4. Type ‘C’ soil (Granular soils, sand, or soil with free seeping water, etc).