## The principle of the

cesspool The waste of life through an inclined sewage pipe passes into the receiving chamber and there are distributed into heavy and light components. In tanks, fecal waters are neutralized during fermentation, oxidation and lose their chemical activity. Therefore, when released into the soil, they are not so harmful to groundwater.

Over time, in the first compartment where liquid debris accumulates, the liquid level reaches the overflow hole, which should be located above the inlet. The heavier components of the waste are deposited on the bottom and decomposed into the sludge under the influence of bacteria. The liquid is poured through the connecting pipe into the adjacent container, in which there is a filtering bottom. Periodically, the system should be cleaned using a sewage system.

If it is decided to make a cesspool of concrete rings, then it is possible to purchase special reinforced concrete with the already cut out inlet-outlet apertures. For the first tank, where solid wastes are deposited, the concrete rings are provided with a bottom.

In order to build a normal fully functioning septic tank, you need 5-9 rings. If there are 2-4 people in the house, then 5 rings are sufficient, if up to 6 people, then 9 rings are required.

## We design the sewerage system:

scheme The scheme is the most important in the arrangement of the sewage system. From the correctness of its composition depends the comfort of living in the country and the effectiveness of environmental protection. In addition, when planning the location of the cesspool, it should be noted that there must be free access of the sewage sys- tem to the storage tanks. All the subtleties of the device should be thought out in advance, since then it will be very difficult to alter the treatment facilities, if not impossible.

If it is planned to drain the treated effluents into the nearest water body, then it should be coordinated with the SES and in accordance with the requirements of SanPin, it is necessary to equip an additional unit intended for post-treatment and disinfection of the drains. The cesspool should be so located on the site that the distance to residential buildings is at least 5 m, and to the water well at least 30 m.

## How to calculate the necessary volume of the cesspool?

The calculation is not complicated. When buying concrete rings, the volume of each type is already known. It is sufficient to multiply the known volume by the number of rings. If the volume is not known, then the hollow cylinder volume formula should be used:

V = πD2H / 4

V- this is the required volume, D is the diameter of the concrete ring in meters, and H is the height.

Sometimes it is easier to look at the tabular volume value corresponding to a certain type of rings: For KS-10.9, the volume is 0.71 cubic meters, for KS-15.9 - 1.59 m3, for Ks-20.9 - 2.83 m3.The type of rings is deciphered as follows: for example, take Ks 10.9, here 10 is the diameter in decimeters, that is, the diameter will be 1.0 meter, and the height is the second digit after the point, i.e.9 - 90 cm.

After calculating the number of rings, do not forget about the overlap, which will close the cesspool. It is a concrete slab with a hole for the hatch. The hatch can be purchased ready, for example, polymer.

## The process of construction of the

- cesspool is excavated. Two excavations are being excavated.
- If the concrete ring with a bottom could not be bought, then the bottom of the first pit should be poured with concrete mixed with rubble. The bottom should be 10 cm thick. The bottom will occupy about a week for full work until the monolith is completely solid.
- Use the crane to set the rings one on top of the other. And, you need to think about the waterproofing, lay the rubber between them, and the joints should be closed with concreting. After all has dried, a liquid glass is applied from above.
- In the second well of the bottom it is not necessary to do the bottom, but we put the rings directly on the ground. However, it is desirable to pre-pour rubble, to get a drain and a kind of filter. So the rings will not sink heavily into the soaked soil.
- We lay pipes in the trench to a depth of 1 m and with a slope of 2-3%.
- We install floors with ventilation and hatches. This will require two pipes with a diameter of 10 cm and a height of 48 and 70 cm
- The inner walls of the septic tank should also be covered with concrete mixed with liquid glass. This prevents the percolation of fecal water into the ground through the joints.
- For more efficient operation of the septic tank and activation of waste decomposition it is possible to populate bacteria in the effluent, which completely disinfect the waste.