In some jurisdictions, there are specific regulations that govern the amount of time and type of inspection that must be performed before a utility or contractor begins construction or digging operations. This is referred to as “ground investigation” or “ground investigation for utilities.” These regulations exist for two primary reasons: first, to prevent injuries to workers on the ground due to unplanned or unexpected hazards; and secondly, to ensure that the utilities in the construction area are not damaged or interrupted by the construction. Ground investigation standards vary by state, county, and municipality. The specific rules will depend on factors such as the type of construction being done, soil type, and geotechnical data available in the area. However, a few general requirements are outlined below.
What is ground investigation?
Ground investigation is the process of identifying potential hazards in the ground prior to construction or digging. The goal of ground investigation is to prevent injuries or disruptions to utilities in the construction area. The investigation is typically done by a certified inspection company or individual who will visit the construction site and perform a thorough inspection. The inspection may include digging a hole of a specified depth in the area where the construction is taking place to take a sample of the soil; taking an electromagnetic (EM) reading of the soil; or drilling a sample well to take a sample from below the surface. The inspection will also look for signs of utilities in the ground, such as underground lines, water pipes, and other pipelines. The inspector may also use ground-penetrating radar (GPR) to check for the presence of underground structures such as walls or foundations.
Regulatory Requirements
There are a few different ways in which the regulatory requirements for ground investigation may differ from state to state. Some states, for example, may simply require the contractor to notify the utility company in writing before any digging begins. Other states may have specific rules and regulations that must be followed in order to comply with the utility and construction work. Some of the most common requirements for ground investigation include the following:
Regulations for digging depths - The regulations may vary from requiring a specific depth of digging to no digging at all. Some states require a certain depth below the surface, while others require a specific height above the water table.
Regulations for identifying utilities in the ground - Some states may require the inspector to follow a specific protocol for locating utilities in the ground. Other states may have no regulations regarding the identification of utilities. Some states may have specific regulations regarding which utilities must be identified and marked in the ground before construction begins.
Regulations for marking utilities in the ground - In some states, the contractor is required to mark all utilities in the ground before beginning construction. In other states, the contractor only has to mark the area where they plan to dig.
Conclusion
The regulations for ground investigation vary from state to state, but there are some basic requirements that must be followed. The inspector will typically visit the construction site and perform a thorough investigation. They may dig a hole, take an EM reading of the soil, or drill a sample well to take a sample from below the surface. The inspector may also use GPR to check for the presence of underground structures. The investigation will help the contractor and utility company identify any potential hazards in the ground and take necessary precautions to prevent injuries or disruptions to utilities in the construction area.