Each owner of a private house faced with the problem of disposal of sewage. The times when people used a street toilet are a thing of the past. New sewage disposal systems are replacing. One of which you will learn in this article. Septic tank, part of a local sewage treatment plant. In the work of the septic tank, the principle of gravity sedimentation and biological post-treatment is laid down, using bioenzyme preparations, as well as soil natural and forced post-treatment methods. These may be biofilters or bio-loading.
There are several types of septic tanks:
- on aerobic bacteria;
- on anaerobic bacteria;
- Using both principles, combined septic tanks ..
Norms and rules governing the installation of septic tanks on the site are:
- Code of Rules 32.13330.2012 “Updated version of SNiP 2.04.03-85“ Sewerage. External networks and facilities. ”
- SanPin 2.2.1 / 2.1.1.1200-03.
Posting Rules
We will analyze the basic rules for placing a septic tank on the site and the consequences that will occur if they are not followed.
The distance from the septic tank to the source of drinking water, a well or a well is at least 30 meters. If this rule is not observed, then the secondary water that has been treated in a septic tank will fall into the source of drinking water. Consequence, poisoning, intestinal disorders. The rule applies to the simplest types of septic tanks, concrete rings. In more complex, sealed, plastic septic tanks that use both anaerobic and aerobic bacteria, the clarified water can be removed by a pump installed in the second chamber of the septic tank through the HDPE hose to any point in the site. The outlet point of the water from the hose is 30 meters from the source of drinking water.
The septic tank must be placed at a point of relief located below the source of drinking water. If this requirement is not met during the spring flood, there is a risk of sewage from the septic tank entering the source of drinking water.
The distance from the septic tank to the foundation of the house is at least five meters. Over time, the soil around the septic tank, in the case of concrete rings, around the second overflow well, or in the case of a septic tank, with soil post-treatment (drainage field), is saturated with moisture.
If the distance between the septic tank and the foundation of the house is less than five meters, for example two meters, then the foundation begins to get wet, transferring excess moisture to the walls of the house. The second reason, if we make the distance of the sewer pipes less than six meters, then the smell from the treatment plant will fall into the house, this will not add comfort to the residents.
The distance from the treatment plant to the public road is at least five meters.
If this norm is not met, there is a risk of getting on the road repair, a pillow of sand and gravel under the asphalt can erode the water leaving the septic tank.
Neighborhood fence at least two meters. Everyone knows how short-lived friendship with neighbors is, which, after some time, can turn into fierce hostility. Therefore, the standard is better to fulfill than to suffer later with the transfer of the treatment plant.
If the septic tank is located in the driving area of the owner’s cars, it must be reinforced with concrete reinforcement from above. We are talking about a plastic septic tank; the passage of cars is not scary for concrete rings. If you save on concrete, you will soon have to repair plastic, which cars can deform with their mass.
The septic tank is instilled at the lowest point of the site. This will save on earthwork, plus, if you do not observe it, and will be located at the top of the site, then the likelihood that the gray cleaned water of the septic tank will get into your home increases.
The depth of the septic tank and the distance from the house
There are several basic parameters that determine the depth of the laying. Consider them so as not to make mistakes leading to additional material costs.
The distance from the house to the septic tank should be at least five meters, but it is also not worth doing much more than the specified value. Sewer pipe has a slope of the order of two centimeters per linear meter. The calculation will show that at a distance of five meters from the house, the pipe will drop ten centimeters. The starting point for calculating the slope of the pipe is taken at least 30 centimeters from the ground to the top of the pipe, laid horizontally on the sand cushion, near the foundation, at the place where the pipe passes through the foundation into the house. These data are based on the experience of many years of installation and operation. To prevent the pipe from freezing at such a depth, thermal insulation is put on the pipe. The opinion that the sewer pipe should be buried below the freezing depth is wrong! Laying the sewer pipe to a depth below 1.5 meters leads to the following errors:
- A septic tank, if it is concrete rings, will be filled by 1/3 of the part if the well consists of two rings.
- If it is a plastic septic tank with soil post-treatment, then at such a depth during the spring flood through the drainage field the treatment station will be filled with flood water and the system will not be able to work.
- With a high level of groundwater in the area, due to the terrain, both systems will also be inoperative.
Install the system no further than five meters from the house, so that the septic tank does not go too far underground, and you will ensure its normal performance even in spring flood. The pipe, in thermal insulation, laid with a slope according to GOST at the starting point of 30 centimeters from the surface of the earth, does not need to be additionally heated with a heating cable, heat is generated during rotting and fermentation in the first chamber of the septic tank, it does not allow the pipe dressed in thermal insulation to freeze. Plus, the wastewater is also warm. If for some reason the sewage treatment plant has to be installed beyond five meters, then through the SNIP every fifteen meters of the pipe in a straight section, at each turn and bend of the sewer pipe, an inspection well is installed.
Small area problems
What to do if you got a small area where it is problematic to comply with all standards and GOSTs:
- Buy a combination plant where aerobic and anaerobic bacteria work. The degree of purification after such an installation can reach 98%, according to the passport. Water can be used for irrigation. The main idea, the cleaner the water at the outlet of the septic tank, the easier it is to dispose of.
- If the septic tank cannot be installed at a distance of 30 meters from the source of drinking water, be sure to put drinking filters on the water, an ideal option is a reverse osmosis system, the degree of water purification after osmosis allows it to be drunk without boiling.
- If it is impossible to place a septic tank farther than five meters from the house, there are two options: to make additional waterproofing of the foundation in the area of the treatment plant, when the house is already built. If the house is still in the project, install it on a pile foundation, which has proven itself in areas with a high level of groundwater.
