SELECTED ISOLATION DISTANCES

1. If safeguards are provided, the minimum distance may be shortened.  Consult Minnesota Rules, Chapter 4725.

2. A water-supply well which has less than 50 feet of watertight casing or which is not cased through a confining layer, such as a clay layer, at least 10 feet thick, must be located at least twice the indicated distance from the potential contaminant source.

3. A well between 5 and 10 feet of an electric transmission line, gas pipe, or LP tank must be placarded and work must not be performed on the well unless the line is deenergized and grounded or shielded, and the gas pipe or LP tank does not contain flammable gas.

4. The 20-foot distance applies to only irrigation wells and chemigation tanks protected with safeguards meeting the requirements of the Minnesota Department of Agriculture.

SOURCE: Complete listing may be found in Minnesota Rules, Chapter 4725.