In a typical residential construction project, the excavation contractor shows up after the surveying crew determines the house and lot boundaries. The contractor removes the soil to the depth required for the new foundation and ensures that the soil is firm through compaction tests and compaction with equipment, if necessary. The dig requirements are precise, so the excavation contractor must be able to use a level and transit to match the grade posted by the surveying crew. After the foundation contractor pours the footers and stem wall, the excavation contractor backfills around the new foundation.