Septic drain lines (or leach lines) are typically buried between 18 and 36 inches underground, and should be at least 6 inches below the surface. These pipes are perforated and surrounded by filtering materials like sand or gravel. Burying the lines at this depth helps minimize odors and allows bacteria and other biological processes in the soil to effectively treat the wastewater. Burying lines too close to the surface can cause issues unless the soil is very compact and stable.

Some two-in-one tools and machines do both jobs, and those could be the right solution for smaller residential projects. However, the phrase “use the right tool for the job” definitely applies to digging. For the best results, get two separate tools for your trenching and landscape edging projects or call a pro to take care of everything for you.

Because decomposed granite is a durable material, a crushed rock or gravel base is optional as long as the DG is properly installed and compacted. However, installing a base is a good idea because it will ensure proper drainage and stability and act as a weed suppressant (although you may still occasionally have to pull weeds). Installing an adequate base can also increase the durability of driveways and walkways. If you forego the paver base or gravel underneath, line the area with landscaping fabric to avoid weeds.

There is no standard depth for burying a septic tank; they are typically buried anywhere from 4 inches to 4 feet underground. The final depth depends on several factors, including the depth of your main sewer line, the height of the bedrock, soil type, local regulations, and the property's landscape. If you plan to grow grass or plants over the tank, a depth of at least 4 to 6 inches is recommended. Deeper tanks can be more difficult to locate, but a septic professional can help find it for you.