The rippability of an earth (rock) material is a measure of its ability to be excavated with conventional excavation equipment. A material may be classified as rippable, marginally rippable or non-rippable. The rippability of a material is often evaluated by an engineering geologist and/or geophysicist utilizing the seismic refraction equipment (see refraction),. Rippability studies can involve the performance of seismic refraction traverses, the drilling of borings with an air percussion drill rig, the excavation of test trenches with a bulldozer with rippers or backhoe, and by geologic mapping. The rippability of an earth (rock) material is a measure of its ability to be excavated with conventional excavation equipment. A material may be classified as rippable, marginally rippable or non-rippable. The rippability of a material is often evaluated by an engineering geologist and/or geophysicist utilizing the seismic refraction equipment (see refraction),. Rippability studies can involve the performance of seismic refraction traverses, the drilling of borings with an air percussion drill rig, the excavation of test trenches with a bulldozer with rippers or backhoe, and by geologic mapping.