First of all, it is important to know what subsurface utilities are. Subsurface utilities are public utilities such as electricity, gas, water and sewage that run underground. Engineering and working with the locating, mapping and overall layout of these utilities is referred to as utility engineering.
The ground is broken with the help of a super sucker hydro vac which utilizes high water pressure to break the earth and remove it with the use of a vacuum, much like the name suggests. Employees that specialize in subsurface utility engineering use these machines in order to get within close proximity of the underground utilities either for repair or construction purposes.