Seepage Pit & Test Hole Drilling

JS has been doing test hole drilling and seepage drilling for 25 years. If you need a new system designed, we can handle everything, from the test hole drilling to the seepage pit installation. If you just require a replacement seepage pit, we can handle that as well.

A seepage pit is a hole in the ground that is lined with either manufactured or site built perforated sides, such as pre cast or cast in place concrete, or built in place with unmortarted hollow cinder or concrete blocks, that receives liquids only.

A seepage pit receives effluent from a septic tank and treats the septic wastewater. Its' function is the treatment and disposal of wastewater; it receives the clarifed effluent from you septic tank. This is unlike a drywell which is used for graywater that comes from your shower, laundry or sinks or other non septic water. The black water leaves your home or building through the main drain, then enters your septic tank. The tank will then retain the solids, grease, and scum allowing for treated effluent to enter the seepage pit that is then released into the soil.

Installing a filter may extend the life of your seepage pit, especially if your pit is used for receiving black water and gray water from your washing machine. A lint filter between the washing machine and the seepage pit can help to extend the life of the pit as well, by reducing the lint and debris into the system. Using any additives is not recommended for septic effluent. For conventional absorption fields and septic tanks, additives are not necessary and can be harmful to the environment, or may destroy your drainfield and you risk contaminating ground water or nerby wells. These products will not repair a failed drainfield.

If your septic tank needs frequent pumping or it has a shorter than expected life span, it could mean that solids are flowing into the seepage pit from your septic tank. If you see toilet paper in the seepage pit, it means the solids are not staying in the septic tank where they belong.

If your seepage pit is not draining properly into the surrounding soil, you need a new one. As long as the old seepage pit is not in danger of collapsing, it is possible to extend the connection from the old pit to the new seepage pit. When your new seepage pit is installed, we can install a filter at the outlet of your septic tank, and we will inspect for damaged or missing baffles to see that they are intact or in need of repair.

Test Hole Drilling

In order to design a seepage pit system, a seepage pit test must first be completed. We use a drilling rig to make a test hole approximately 50 ft in depth that is then filled with water. Once the soil is presoaked, a seepage pit percolation test is performed. The water level is measured to see how quickly the water drops by soaking into the bottom and sides of the hole. This percolation rate is used to establish the Soil Absorption Rate which is the volume of liquid that soaks into the soil every day in a square foot of sidewall of the pit.