Also, put in an effluent filter (Zabel, Orenco or other) and make sure there is a distribution box to allow you to "rest' leaching areas for double the life of the system.
If you have clays or lots of fines, you can apply gypsum to offset later problems related to sodium binding.
Measure and map the system for location purposes in future years.
If your state allows separate "gray water" disposal, read the rules and set up a separate drainage system for the washing machine.
Do not add a garbage grinder or water softener.
Install an effluent filter and access port - the fewer solids to the drainfield, the longer it will last.
Make sure it's level, and make sure you attach a piece of garden hose or plastic rope to the handle of the clean out cover. Covers are often buried under dirt and when it comes time to clean the septic tank you can never find the lids. The piece of rope can lie on the surface and becomes embedded in the grass. Its easy to find in a few years. If you can afford it, make it a minimum of 1,200 gallons. Bigger is better, more retention of solids and better effluent quality. Good luck.
One of the best things we have done is to specify manhole covers to the surface above the septic tank. This makes it much easier to inspect systems for real estate transactions, and for pumping.
I would recommend the integral type baffles rather than pipe tees, also. They are less prone to breaking and cracking.
If you are using a D-Box, be sure all of the outlets are the same elevation so the trenches are used evenly. This will prolong the use of the leaching area. There are some dial-type levellers that are useful for this.
SepticProtector offers a filter for washing machines which prevents fibers from clogging drainage soils...these travel out to the soil and do not settle out.
Manhole covers to the surface above the septic tank? Be careful! This makes it much easier for Johnny to push his little sister into the tank. Make sure the lid locks or weighs 80 pounds.
1. Do laundry in small doses. Any more than 2-3 loads in a day can result in major problems with hydraulic overloading of the tanks and ultimately the field.
2. Don't install a sprinkler system on top of your drainfield. If you need to water to establish new grass, use a hose-end sprinkler. In-ground sprinklers have a tendency to apply too much water and can interfere with evaporation.
3. Put in as much system as you can afford. If you oversize initially, you will probably not have to add more system drainfield later.
I find it easier to install two tanks. The first takes the sewage and the second takes waste water. Both tanks are connected. I then install a small submersible pump into the second tank. The outlet can be piped anywhere you like away from the tanks and buildings. Also the outlet can be attached to a sprinkler system for watering etc. Note: for rural areas.
[Caution, Janet H. sends a Health Alert about this suggestion: "Wastewater from a septic tank, even wastewater that has gone through a second tank, contains disease-causing bacteria and other organisms, and is a health hazard. It must get further treatment in a soil treatment area (drainfield, mound system, etc.). Even wastewater that has received treatment beyond the septic tank must be disinfected before use as irrigation water. Talk to a professional about septic systems for more information."
from Pumper magazine:
A new product has been introduced by CAG Sim/Tech Filter of Boyne City, MI. The new filter is designed to prevent clogging the holes of distribution piping used in sand mound septic systems. The filter is installed on the pressure side of the effluent pump which allows for greater efficiency and easy installation. The company recently received approval in the state of Wisconsin, a leader in pressurized mounds. Currently the filters are begin used in septic systems in Pennsylvania, Wisconsin, Missouri, Kentucky, Illinois, and Michigan. With more mound systems being installed all the time, the need and the potential for this new product is tremendous.
Note: The area code of Boyne City is 616, but directory assistance has no listing for this company.
Caveat: Check with your local authority before using any of these ideas.