Septic Tank Leach Field Installation
- 1). Design the layout of your leach field with the spray paint. For most houses of three bedrooms or less, 150 10-foot lengths of four-inch perforated PVC drainage pipe will provide about 4500 square feet of drainage area, which is usually adequate. Unless you are able to design a trench that will fit all 150 sections of 10-foot pipe consecutively, you will have to design 90-degree bends and/or "T" junctions into your field. Measure your spray paint markings to make sure you have designed the field to at least the minimum amount of length.
- 2). Dig the trenches of the leach field at least one foot deep using the shovel and pick. Dig the trenches at least one foot deep and eight inches wide (use the tape measure to check), and gradually deeper as they progress farther from their beginning.
- 3). Check and adjust the angle of the trenches using the twine, level, tape measure, and shovel. Press a stake into the ground at the beginning and end of each length of trench, and span a length of twine between these stakes, pulling it tight before tying it off. Use the level to make sure it is precisely horizontal. Use the tape measure with the twine to check whether the trench's depth declines at a rate of 1/8-inch for every foot, and dig out or fill in the trench with the shovel as necessary to achieve the desired angle of decline.
- 4). Use the shovel to insert gravel into the trenches, spreading it evenly into the base of each trench about two inches deep.
- 5). Lay out the PVC pipe alongside the trenches. Arrange the pipes so that male pipe ends are adjacent to female connections and fittings, and use the hacksaw as necessary to cut off sections that are too long.
- 6). Glue the pipes together with the PVC cement. For each connection, apply the glue (with the container's provided brush) around and around the male end of the connection, and press the sections together for at least 20 seconds. Glue the sections together from the beginning/top of the trench field, work your way to the lower ends, and make sure that the perforations in the pipes face down.
- 7). Insert the pipes into their concurrent trenches, and fill the trenches with gravel using the shovel until the pipes are covered by about two inches of gravel. Replace the soil from the trenches using the shovel.
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