Abstract: A covering is provided for the upper extremity of a circular cylindrical casing wall of a well for potable water. The covering supports a pump positioned within the well and provides thermal insulation so that the water will not freeze when pumped from the well to underground distributor lines. The covering or cap is comprised of a lower member having an outer vertical sidewall and interiorly disposed support beams, an upper member which seals the lower member, and a cylindrical tube that transfers water from the well to underground distributor lines.