Mason County, West Virginia Septic System Rules

Permit

All new individual septic systems installed for dwellings or buildings in Mason County require a permit. The application must be submitted to the county Department of Health, along with the plans and layout of the type of septic system being installed. Soil test or percolation test results must also be submitted with the permit application.

New septic systems cannot be installed in poorly drained areas of Mason County, or any area where seasonal flooding occurs. The only exception to this rule is if the contractor presents evidence to the commissioner that the area is suitable -- and the soil can handle the sewage disposal. The septic system must also be at least 10 feet away from the property line or any building located on the property. No sewage lines, tanks or leach fields can be within 25 feet of public water supplies or within 10 feet of private water supplies. The septic tank must also be a minimum of 50 feet away from any groundwater supply or private water well.

Mason County, as well as the rest of West Virginia, requires that the septic tank must be sized, according to the size of the residence. For example, a single-family home with four bedrooms or less, must have a tank capacity of 1,000 gallons or larger. For each additional bedroom, the septic tank capacity must be increased by 250 gallons. In dual tank systems, the first tank must hold twice as much as the second tank. The pipe attaching each tank must be at least four inches in diameter. The septic tank must be made of reinforced concrete, fiberglass or watertight material approved the health commissioner.

The leach field for a septic system in Mason County must use four-inch pipes. The number of trenches for the leach field is determined by the size of the septic tank. The distribution pipes must be a minimum of two feet below the ground. The trenches must have washed gravel, crushed stone or slag 1.0- to 2.5-inches in diameter. The seep pipes used in the leach field must have a minimum of two rows of seep holes running the length of the pipe that face down and that are situated approximately 90 degrees apart.