Q&A for How to Install a Septic System

The tank does need to be level. It is hard to say what it will affect, not knowing which way it is off level.

It depends on the species of trees growing near or above your lateral lines. Some tree species have a tendency to grow roots into the lateral lines, clogging them. However, grass, weeds, and bushes rarely effect them since they are buried deep and are surrounded by a pocket of gravel to bleed away waste water.

Most systems require 12" of rock. The perforated pipe should be suspended in the upper portion of the rock.

Your field does have to breath. Green grass over your field means it's working fine. Your field can breath with green grass over it. No woody shrubs or trees should be planted over the leach field.

Fifty feet minimum. The law varies from state to state, but this is the most common distance.

Depends on how cold it gets. In northern U.S., no less than 12" of dirt over leach field.

It depends on whether or not you live in a region where the ground freezes.

None. A common tank is 1,000 gallons and will fill up relatively fast with regular use. The point is to hold and pre-treat solids as the liquid effluent flows out to the drain field. A pump system could require water to prime the pump.

As long as you have good flow downhill. I would use two 45's instead of a 90.

After the system has been installed, but before it has been covered up with soil. Always call the inspector before starting to ensure they can accommodate your inspection.

The outlet will be 2" lower than the inlet from the top of the tank.

Yes, it is much better to have the tank padded with sand or small grain gravel.

Buy regular baker's yeast at the grocery store, open and put two or three packets in the commode and flush. That's all you need to do. Or purchase the microbes at Lowes, Home Depot, etc.

This is likely a clean-out. It should not be disturbed since it may prove useful in the future.

For a conventional (lateral) system, yes, and capped. Make sure you make a map so these can be found at a later date. Use GPS if possible. If the unit is a sand filter, I would not cut them off.

This varies by local regulations. In Iowa, the tank must be 50' from the well. Secondary portion (laterals) of a conventional septic system must be 100' from well.

No, you will not need to add water to a new tank. Once you flush it for the first time, it should be set up properly.

Shouldn't be a problem, but don't put any concrete close to the line. Make sure your posts are on either side of the line and not directly on it.

Use hydraulic concrete and forms that are above the water line. Fill until it replaces the water. Wait until it has cured to do anything else.

Your system has no certified tank. The owner buried a steel tank and ran lines off of it.

It should be installed in the general vicinity (close) of the perc test. If you move it too far, the system may not drain waste water away adequately.

You'll have no wastewater backup into your toilets and drains, no foul odors emanating from your leach/drain field, and no spongy grass in your leach/drain field that highly contrasts with your other grasses in other surrounding areas.

If you are going to use a rubble-trench, you must also use pea-gravel (~1.5 inch washed stone) throughout. Spaces between the concrete rubble need to all be filled with the pea-gravel. This is to prevent soil particles from seeping in and filling up your trench too much. An obstructed leech/drain-field can lead to a failure of the septic system. It may also be a good idea to line the sides of the trench with special filter-fabric in order to further prevent soil particles from infiltrating your trench.