A specialty classification that involves clearing, grading, excavating, digging, moving, cutting, filling, backfilling, trenching or placing material forming the surface of the earth with hand and power tools or machines. The scope of work includes hydrovac excavation, dewatering, soil retention systems as well as installation, maintenance or construction of storm sewers, drains, channels, conduits, box culverts less than 20 feet or other systems for carrying off excess water. Box culverts greater than 20 feet require the major classification of Hwy, Street and Bridge. This specialty classification does not include sanitary sewer systems which fall under the major classification of Municipal and Public Works.