Ground waters are between a soil layer and the first waterproof rock sheet, that is in the first water bearing layer from a surface. Ground waters collect due to infiltration through the soil of a surface water and precipitation.
Instruction
1. Ground waters fill cracks in sedimentary and magmatic rocks and also a time in slightly cemented and friable breeds. Ground waters get to breed generally due to infiltration through the soil, thus, waters of lakes and rivers, an atmospheric precipitation become a source of ground waters. Ground waters can be also replenished due to rise from the lower water-bearing layers, that is at the expense of deep-well waters.
2. Ground waters differ from other underground waters in the fact that over them there is no waterproof layer therefore in them there is no pressure, they not completely fill breed. If to dig the well reaching ground waters they will just fill it on the same level at which they were if to dig out the well to deep-well waters, water level in the well will be much higher, than in the water bearing layer.
3. Ground waters have the identical fields of distribution and food therefore their level and structure depend on a season: in the summer their level goes down, in the period of a flood - sharply increases.
4. Ground waters usually have a weak mineralization as because of continuous updating of water in a layer, breeds are quickly leached. In droughty regions, ground waters may contain rather large amount of salts.
5. Many lakes and the rivers eat at the expense of ground waters which come to a surface in the form of springs. As it is easier to extract ground waters, than artesian, at an opportunity for water supply use them.
6. It is possible to determine pollution of the area by ground waters if they are infected, the ecological situation very bad means. Ground waters near the NPP, the chemical companies, cattle mortuaries, dumps cannot be used.
7. At construction of constructions it is necessary to conduct surely a research of ground waters of the site, they can seriously affect stability of the building.