What are the major indicators of water pollution ？
(1) Biochemical Oxygen Demand (BOD), said the oxygen conditions, water aerobic microbial oxidation and decomposition of organic unit volume consumed in the amount of free oxygen; (2) Chemical Oxygen Demand (COD), only a strong oxidizer -- potassium dichromate, the oxidation of organic matter in water under acid conditions will be measured by the oxygen consumption and carbon dioxide; (3) the total oxygen demand (TOD), refers to the oxidation of organic matter entirely COD; (4) total organic carbon (TOC), said the total carbon content of organic pollutants in sewage water; (5), suspended solids by filtration determination of the filter membrane or in withholding from the material on the filter paper; (6) toxic substances that have reached a certain level, on human health, The growth of aquatic organisms harmful substances, including arsenic and cyanide and heavy metals-the heavy metals mercury, cadmium, chromium, lead, the international community recognized the six Toxicology; (7), the pH value is a reflection of the strength of the important indicators of water acidity; (8) the number of coliform bacteria, coliform refers to the number per unit volume of water contained

What is the sewage system ？

Charging system for the discharge of pollutants to the environment polluters and pollutants emitted by the variety, quantity, concentration, according to the relevant provisions of charging certain fees, characterized by use of a certain value to the financial pressure on polluters to make sure that they reduce or eliminate the emission of pollutants. In 1979 the "People's Republic of China Environmental Protection Law (draft)," China's first formal sewage system. In 1982 the State Council promulgated the "Interim Measures for sewage charges" after the implementation of the sewage system. The main contents are : the sewage system, including the general scope of effluents and emissions (dust) and sludges, individual provinces also says that noise pollution is also charged; Depending on the type of charges, quantity, concentration, the degree of harm; Collect sewage charges and the specific relief measures and the management and use of sewage charges

How to determine the environmental impact assessment system ？

Environmental impact assessment system is a widely used industrial countries in environmental management systems. 1969, the United States as the first environmental impact assessment, environmental management in the federal government must follow a system. , The other industrial countries have begun to establish such a system. In 1979, the "PRC Environmental Protection Act (Trial)," the system provides for the environmental impact assessment report. 1981 in the "infrastructure projects, environmental management approach" to environmental impact assessment of the scope, content and procedures specific provisions. Also on the management of 1986 was amended by the National Committee for Environmental Protection and Planning Council, the National Economic Council promulgated the "management of the construction project environmental protection". Since then, the environmental impact assessment to determine the current system. The late 1980s, the environmental impact assessment by the evaluation of the isolation of a single project started in the comprehensive evaluation of regional development. The late 1990s, the factory gradually began an environmental impact assessment, and the ISO14000 environmental management system integrating environmental assessment

What is a small heavily polluting enterprises ？

It is based on the "State Council's decision to Environmental Protection" established that all the production process, backward technology and equipment in the production process consumption and waste of resources, energy, too much to have a significant impact on the ecological and environmental damage and endanger human health, and difficult to create economies of scale manufacturers. The first ban, shutting down or stop production of small heavily polluting enterprises, such as the 5,000 tons of small paper mills, tanneries, production of less than 30,000 of the tannery, with an annual output of 500 tons of dye works and primitive forms of coking, small enterprises producing sulfur, 1919 arsenic, mercury practicing, practicing, lead, zinc, oil refineries, elected reserves pesticides, bleaching and dyeing, electroplating, and the production of asbestos products, and 15 kinds of small radioactive products of heavily polluting enterprises, listed "15 small"; subsequently identified five species, such as small iron and steel plants, cement, glass, small coal enterprises, "new five small" 。

What is the volume control ？

It is based on the functional requirements and use of self-purification ability of a body of water, pollution sources to control the amount of pollutants discharged by the management, the basic starting point is to ensure the water quality restrictions on the use of functional requirements. The total for the implementation of the prevention of water pollution control, first through the development of regional water planning, and the formulation of the major sources of pollution discharged into water bodies and enterprises in the total amount of pollutants allowed, but also with businesses planning to control the total volume of pollutants discharged to the total amount of mutual harmonization. The amount of pollutants will change the water quality objectives for the loss of overall control environment indicators, the implementation of enterprise management, it is issuing discharge permits under the supervision departments of environmental protection, as well as one of the fundamental basis for enterprise management. Taking into account the natural characteristics, and to identify environmental pollutants in the proliferation, migration and metastasis and the purification of the law, the calculated capacity of the environment, and a comprehensive analysis of the sources of the region, through the creation of a digital model, the calculated each source of pollution rate and the corresponding share of the total emissions of pollutants allowed to seek the best option, pollution emissions so that everyone can discharge less than the total emission standards 。

What is the environmental monitoring ？

It is the environmental study area or continuous measurement of the concentration of the pollutants in the environment, its changes and its impact on the environment, and also a great social significance, the quality of the environment to reflect the true situation, the judge whether the pollutant discharge standards, pollution dispute arbitration and pollution treatment process. Monitoring data will play a key role, which requires monitoring data that is fair and legal. However, in many areas of the monitoring data is often subject to the influence of various factors, therefore, constitute most of the environmental monitoring from the quality assurance system : (1) The basis for environmental monitoring to ensure the quality of work; (2) Environmental monitoring of the entire process of quality assurance; (3) the quality of accidents and errors; (4) the quality of complaints handling. Before 2:00 contain a variety of content and requirements, the system is the main content of the last two points is the quality of doubt, mistakes and incidents, conducting investigations, identification and treatment measures, as well as the essential component of quality assurance 。

What are the policy tools to control pollution ？

In selecting pollution control methods, a variety of considerations, such as equity, efficiency, practicability and economic efficiency is only one of them, and the policy tools can be roughly divided into three categories, namely, the standards and sewage charges and emissions trading. Emission standard is the world's most widely used method of pollution control, and law enforcement departments from the management of each specific sources of the pollutant discharge limits. Sewage charges against sewage enterprises to air, water, soil or waste emissions and noise produced charges levied on the amount of sewage discharged waste with the quantity, quality and the losses caused to the environment. Emissions trading refers to the total amount of emissions cap management departments, according to limit payment of a permit, a permit can be put on the market. And the method of payment of the initial amount of emission rights under the environmental protection goals set by managers, in accordance with the rules of emission rights can be issued once the free exchange

What is the pollution of water bodies ？

Water pollution is a certain amount of sewage, wastewater, and all kinds of debris and other pollutants into the waters beyond the water purification and pollutant carrying capacity, resulting in a body of water and sediment in the physical and chemical properties and biological communities composition adverse changes undermined the inherent water ecosystems, damage the water body functions, thereby reducing water use value of the phenomenon. Water pollution caused by the wide range of factors : water discharge to the city life was not proper treatment of sewage and industrial wastewater; Application of chemical fertilizers, pesticides and pollutants from the surface were washed away, with the surface runoff into water bodies; With the proliferation of toxic substances in the atmosphere or by gravity into a body of water, such as precipitation. Water pollution is the first of the major factors. With the development of industrial production and socio-economic prosperity, and a large number of industrial and domestic wastewater discharged into a body of water, an increasingly serious water pollution 。

What is the pollutant discharge standards ？

Pollutant discharge standards is the major content of hazardous substances into the environment and cause harm restrictive provisions of pollution, with a focus on the concentration of pollutants discharged restrictive regulations, in addition to its established link with the environmental quality standards, but also determined the pollution control technology and economic viability. The most important air pollutant emission standards for pollutant discharge standards and water pollutant discharge standards, China's existing national standards, including air and water emissions from industry and integrated emission standards. As the regional sources of the type, quantity, and the self-degradation of pollutants in different degrees, even in some areas to meet the requirements of the pollutant discharge standards, environmental quality is not necessarily meet the standard requirements, the need to increase the limit on the total volume of pollutants discharged 。