The groundwater

Underground waters are waters that are in a solid, liquid or vapor state in the upper layers of the earth's crust, in the thickness of rocks. They relate to the resources of the hydrosphere. In the regions where such waters are located, the temperature is in the range from minus ninety three to plus two thousand two hundred degrees, and the pressure in their thickness ranges from several units to three thousand MPa.

Underground water resources are divided by their location into the following types:

- pore, located in pebbles, sand and various detrital rocks ;

- cracked or veined, flowing in sandstones and granites;

- karst, located in gypsum, dolomite, limestone and other soluble rocks.

Gravitational or free waters move under the influence of gravity. In contrast, associated water resources form strata in the rocks or horizons.

The very first from the earth's surface is a layer that exists without pressure. It is called the "groundwater horizon". Its depth is directly dependent on the geographical location of the area. The change in the occurrence is from the poles to the equatorial zone.

In European regions of Russia, the average depth of the horizon of the soil layer increases gradually from the northern to the southern regions. If in the tundra zone groundwater is located directly at the surface of the earth's crust, then in the southern regions - at a depth of several tens of meters. The maximum depth of occurrence of these water resources ranges from ten to twelve kilometers.

Groundwater is a solution, which includes more than sixty chemicals, as well as various microorganisms. Basically, these hydro resources have a saturation with gases. The waters in the upper layers of the earth's crust are subdivided into species depending on the degree of saturation with minerals. Distinguish:

- Fresh;

- brackish;

- salted;

- underground brines.

The origin of groundwaters is reflected in their type classification:

1. Infiltration layers are formed by percolation of river, rain or meltwater from the earth's surface.

2. Condensation horizons are the result of processes of condensation of water vapor in cracks or in pores of rocks.

3. Sedimentary underground hydro resources are formed as a result of sedimentary formation of a geological type. They, as a rule, are buried waters of marine origin. This includes the ultra-fresh layers located in moraine deposits, as well as the salt basins.

4. Groundwater, related to the magmatogenic type, originated from magma, which passed the crystallization process, as well as from rocks as a result of their metamorphism.

Most of the quantitative and qualitative indicators (pressure level, flow, gas and chemical composition, temperature, etc.) of ground layers are subject to both short-term and long-term changes, which determine their overall regime. At the same time, the greatest variability of the characteristics is manifested when the water layers are not deep-seated.

Hydro resources located in the upper layers of the earth's crust are classified as renewable minerals. In order to protect against depletion and pollution, monitoring of groundwater is monitored to control operation, as well as to prevent negative consequences during water intake. The organization, as well as the management of these control activities, is a direct responsibility of those legal entities that have obtained a license for the extraction and use of natural water resources. In the production of monitoring, a survey of the sanitary zone of water intake is also conducted. These works are designed to identify sources of probable groundwater contamination and recommend guilty economic agents to eliminate violations.