But this should not comfort. Clear sewage is still necessary to precisely defined standards, but not to the extent of water pollution. The question of where will be given stock, is a priority in the construction of local sewage treatment plants, therefore, all further actions will be determined by a sequence of precisely this solution. Choosing to do the following considerations: the type of soil on the site, its permeability, available area, the groundwater level water and the nature of their use, distance to the nearest body of water (which could take treated sewage) and the estimated construction costs. It is because of all these factors, as well as buffer zones and should project created a system cleaning. The sanitary protection zone – it is the minimum allowable distance from the treatment plant to the object of human life. In the case of residential building, the following sanitary areas: for the septic tank – 5 m, for aeration equipment – 8 m for soil disposal systems – 8-15 m, and in the case of filter trenches and sand and gravel filters – all 25 meters distance to the nearest source of water intake must be at least 20 meters, and it provided that there is no connection between the source supplying the aquifer and soil by absorbing the waste water.
Distance to road is not less than 5 m. The finished project should be approved by several state institutions, including sanitary and epidemiological service, environmental police and water departments. To wastewater treatment system to serve a long time, not delivering troubles and worries, it is necessary to follow a few rules.