The non-point pollution source, also known as the surface source, refers to the wastewater that has dispersed or evenly entered the water body through the shoreline and the natural precipitation that enters the human body through the ditch. It mainly includes urban drainage, farmland drainage and rural domestic wastewater, mine wastewater, scattered small livestock farm wastewater, and polluted wastewater caused by atmospheric pollutants entering the water body through gravity sedimentation and precipitation. Non-point source pollution is complicated, and its pollution impact is difficult to quantify, but it cannot be ignored. Especially after the point source has been effectively controlled, non-point source pollution will become increasingly prominent
Non-point source pollution has two broad and narrow definitions: broadly refers to various environmental pollutions without fixed sewage outlets. The narrow sense is usually limited to non-point source pollution in the water environment, that is, surface runoff pollution accompanying the precipitation process.
In recent years, with the concern of people on environmental issues, a kind of environmental pollution problem that is very common and not familiar with people has been highly valued by the environmental protection departments of various governments. This is non-point source pollution, domestic literature or The media also refers to non-point source pollution, which is often referred to as “non-point source pollution” in the more formal and academic literature. It is translated from the English “Non-point Source Pollution” (referred to as NSP pollution). Come over, so it is more accurate to use “non-point source pollution”. Non-point source pollution has two broad and narrow definitions. In a broad sense, it refers to various environmental pollutions without fixed sewage outlets. The narrow sense is usually limited to non-point source pollution in water environment.
The basic content of non-point sources of pollution survey –
Select all or part of the following to investigate according to the needs of the evaluation work:
(1) Overview of non-point pollution sources: the location of raw materials, fuels, wastes, the area of stacking, the form of stacking, the floor covering of the stacking place, the degree of cleaning, and the way of covering the piled objects.
(2) Discharge methods, discharge destinations and treatment of non-point pollution sources: It should be stated whether non-point source pollutants are organized or unorganized; whether they are discharged directly after concentration or after treatment, whether they are discharged separately or with production wastewater Or domestic sewage discharge together.
(3) Sewage data of non-point pollution sources: According to the existing measured data, statistical reports and the main water quality parameters selected according to the physical, chemical and biochemical properties of raw materials, fuels, wastes and wastes causing non-point source pollution, Investigate data on emissions seasons, emissions periods, emissions, emission concentrations, and other changes.