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The Casing and Cementing Process

In modern times, a well is protected from contaminants to ensure safe drinking water. This is done by inserting a long pipe in the drilled hole, called a casing. Having a casing, however, is not enough. Leaving the end of the pipe open is an invitation for small animals or debris to fall in. Because of this, local and federal health departments have strict criteria for well casing and cementing of the well opening. These design standards must be followed closely to ensure public health.

  1. Federal Guidelines

    • According to the Environmental Protection Agency, the well casing must extend at least 18 feet below the surface. Another requirement is the casing must penetrate the bedrock by at least 5 feet. This is to prevent groundwater seepage from penetrating the well. Groundwater, more often than not, contains contaminants, such as pesticides. Another requirement is the area around the well opening must be cemented. The well opening must be tightly sealed to prevent infestation. All these requirements are laws, and the well installer has to abide by them.

    Casing Installation

    • Well casing is usually available in 10-foot lengths. As the well is being drilled, the casing is inserted in the hole behind the bit. Another method is to drill the hole first and insert the casing once the hole is made. The overall goal, by whichever method is used, is to seal the hole from groundwater contamination so only deep aquifer water enters the well casing hole from the bottom.

    Cementing Installation

    • After the casing is installed, a cement pad must be poured around the casing. This is to seal the casing near the ground and provide a surface to build the well house. The exact size of the concrete pad varies from municipality to municipality. For example, the state of Tennessee requires a concrete box around the top of the casing with a wall thickness of at least 2 inches. Other states have different requirements, and the installer must prove he adhered to the codes.

    Permitting Process

    • Before any work can be done, the local health or building department must issue a permit. The process for obtaining a permit includes submitting a blueprint to the authorities. On the blueprint, the location of the well on the land is specified. Other data presented includes a detailed drawing of the well casing and cement. For the state of Hawaii, a special cement, called grout, must be poured around the casing as well. To pour grout, the installer drills a large hole, places the casing in and fills the gap between the casing and the hole with grout.

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