Surface Casing Overview
Casings are long pipes made of steel or plastic which line the new well to prevent collapse during drilling and contamination of the water below. Between the well wall and the casing is a two-inch gap called the annulus. This is filled with gravel and capped with cement for the last twenty feet to the surface to prevent contaminants from the surface getting into the well and ruining the water source supplying it. Casings also help protect the well from freezing in extreme cold during the winter months.
Concrete Well Casing
Concrete casing is a great solution when the drilling site contains a considerable amount of shifting earth. Being able to pour the casing allows you to fill the gaps.
Steel Well Casing
Steel casing for water wells has been the material of choice for most of the last century. Steel casing can withstand the high temperatures generated by curing cement grout.
PVC Well Casing
PVC is a thermoplastic material that is very resistant to pH corrosion, is not conductive, and therefore is not susceptible to galvanic corrosion, making it a better choice in many cases.