A. Soil borings are the best methods to determine the bearing capacity of the soil at various depths. This is the preferred method to ensure that piles are past the active zone (zone of seasonal moisture change) in areas with expansive soils. A soil boring is different than a test pit, which will generally only give you information relative to the upper surface layer (eight to ten feet). A secondary benefit is to provide recommendations relative to depth, helical configurations etc., thus enabling installers to more accurately develop estimates. When ordering a soil boring you should ask for a standard penetration test, which goes to competent soil or refusal.