Most underground rocks have a lot of water. If you dig a small moat as African elephants do, you can even get in the desert. This could really be a lot. There are also large-scale waterborne underground rivers that can be significantly distant. In fact, a significant part of the earth’s crust is made up of water, that’s why it’s so easy to successfully dig around well over the world. This water can be saturated by microorganisms and large amounts of mineral impurities. Its composition relies on salt or fresh water proximity to the soil and seasonal nature. Mostly, large groundwater occurs at a depth of 3 meters
Domestic wastewater comes in large quantities from residential and public buildings, laundries, canteens, hospitals, etc. In wastewater of this type, various organic substances , as well as microorganisms, predominate , which can cause bacterial contamination.
A huge number of such hazardous contaminants, such as pesticides, ammonium and nitrate nitrogen, phosphorus, potassium, etc., is washed off from agricultural areas and enters water bodies without any purification, and therefore has a high concentration;
The gas-smoke compounds (aerosols, dust, etc.) that are deposited from the atmosphere on the surface of the catchment basins and directly on water surfaces are of considerable danger.
The scale of oil pollution of natural waters is enormous . Millions of tons of oil annually pollute marine and freshwater ecosystems in case of oil tanker ship accidents, oil fields in coastal zones, ballast water discharges from ships, etc.
In addition to surface water, underground water is constantly polluted, primarily in the areas of large industrial centers.
Infiltrating and seeping through the soil, water carries with it to the groundwater all soluble substances in it. The soil can not hold them back. Consequently, any chemical substance used, placed, spilled, spilled on the ground or caught in it, can contaminate groundwater .
According to ecologists, pollution levels in water bodies of both types, though not directly, but very much depend on each other. Similarly, the purity of ground and even the atmosphere depends indirectly on the purity of groundwater.
Often the sources of penetration into the underground water of harmful impurities are all the same sewage – industrial and domestic – leaking underground from storage facilities or sedimentation tanks. By penetration of contaminants there can be old, faulty wells, karst funnels.
The danger of pollution of underground water bodies is that water poisoned by foreign substances does not remain in one place, near the source of pollution, but spreads through a territory that is difficult to determine. And not infrequently, it can seep into underground sources of drinking water.
Currently, the main sources of groundwater pollution are:
• improperly arranged landfills and other stores of poisonous substances from where they can infiltrate into groundwater;
• flowing underground reservoirs and pipelines. A particular problem is the leakage of gasoline from tanks at gasoline stations;
• Pesticides and fertilizers used in fields, lawns, in orchards;
• salt, which is sprinkled with roads in ice;
• Fuel oil, used on roads to bind dust;
• excess of wastewater used in the economy and sewage sludge;
• leakage during transport.