Drinking water must be safe in terms of epidemics and radiation, harmless in chemical composition and must have favorable organoleptic properties. Water quality in general refers to the characteristics of its composition and properties, which determine its suitability for specific types of water use; in this case, quality indicators are signs by which water quality is assessed.
Rationing chemical substances in the aquatic environment has some features.
From a hygienic point of view, the level of contamination of water intended for household, drinking and cultural purposes is assessed. However, water quality standards do not apply to the entire water use facility, but only to water use points for the population. This takes into account both the direct effect of chemical pollutants on the body (sanitary toxicological indicator of harmfulness) and changes in the organoleptic properties of water and the processes of self-purification of water in reservoirs (organoleptic and general sanitary indicator of harmfulness). hygienic chemical quality water
For all water bodies used by the population (surface and groundwater, drinking water, water from hot water supply systems), uniform hygienic standards are established. This is due to the relatively low efficiency and high cost of water purification systems at water supply facilities. From a hygienic and economic point of view, it is much more effective to prevent pollution of water bodies than to purify already polluted water.
Features of hygienic regulation of chemicals in the aquatic environment include the need to study stability chemical compounds, their transformation processes (under the influence of natural self-purification processes, water treatment processes, wastewater treatment, disinfection, etc.). At the same time, the impact on the water body and the organism of mammals is assessed not only of the initial substances, but also of the products of their destruction and transformation.
The MPC is the lowest of the threshold concentrations established according to various criteria of harmful effects.
Maximum permissible concentration of a chemical substance in the water of water bodies for domestic, drinking and cultural water use is the maximum concentration of a substance in water, which, when entering the body throughout life, should not have a direct or indirect effect on the health of present and subsequent generations, including in the long term life, and should not worsen the hygienic conditions of water use.
For essential elements that enter the human body mainly with water (for example, fluorine), both upper and lower limits of permissible content in water are regulated.
In desalinated water, subject to correction for salt composition, the minimum content of calcium (30 mg/l) and magnesium (5-10 mg/l) is standardized.
Along with the MPC, the official lists of standards indicate the hazard class and the limiting sign of harm by which the MPC is established: sanitary-toxicological (s.-t.), general sanitary (general), organoleptic (org.) with a decoding of changes in the organoleptic properties of water. These changes can manifest themselves in a change in the smell of water (zap.), an increase in turbidity (turbidity), the appearance of color (okr.), the formation of foam (foams) or a film on the surface of the water (pl.), and the appearance of opalescence (op.).
For substances whose prospects for use have not been determined, a temporary hygienic standard is established for 3 years - an approximate permissible level (ATL). The ODU is developed on the basis of computational and express experimental methods for predicting toxicity and is applied only at the stage of preventive sanitary supervision of enterprises being designed or under construction, or wastewater treatment plants being reconstructed.
If several substances of hazard classes 1-2 are present in water, the sum of the ratios of the actual concentrations of each of them to their MPC should not exceed one. When several substances of other hazard classes are simultaneously present in water, quality control aquatic environment carried out on the basis of individual maximum permissible concentrations.
Along with hygienic standards, in our country there are maximum permissible concentrations and maximum concentration limits for substances in the water of fishery water bodies. MPC in the water of a fishery water body is an experimentally established fishery standard for the maximum permissible content of a pollutant in the water of a water body, at which there are no consequences that reduce its fishery value.
Hygienic and fishery standards are used to establish standards for maximum permissible discharge (MPD) of wastewater into water bodies. The MPC value is calculated for each specific source pollution and aims to prevent the existing water quality standards of a water body from being exceeded.
Toxicological indicators of water, characterizing its harmlessness chemical composition, are determined by the content of chemicals, which should not exceed established standards.
Finally, when determining the quality of water, organoleptic (perceived by the senses) properties are taken into account: temperature, transparency, color, smell, taste, hardness.
The maximum permissible concentration in the water of a reservoir for domestic, drinking and cultural water use (MPCv) is the concentration of a harmful substance in water, which should not have a direct or indirect effect on the human body throughout his life and on the health of subsequent generations, and should not impair hygienic conditions. water use conditions.
The maximum permissible concentration in the water of a reservoir used for fishing purposes (MPC) is the concentration of a harmful substance in the water, which should not have a harmful effect on fish populations, primarily commercial ones.
In hydrochemical practice, the method of integral assessment of water quality is also used, based on the totality of pollutants contained in it and the frequency of their detection. Also water quality assessment and comparison current state of a water body with the characteristics established in previous years are carried out on the basis of the water pollution index (WPI) based on hydrochemical indicators. This index is a formal characteristic and is calculated by averaging at least five individual water quality indicators. The following indicators are required to be taken into account: concentration of dissolved oxygen, pH value and biological oxygen demand BOD5.
Water quality and water uses
Water quality in general is understood as a characteristic of its composition and properties that determines its suitability for specific types of water use (GOST 17.1.1.01-77), while quality criteria are the characteristics by which water quality is assessed. The maximum permissible concentration in the water of a reservoir for domestic, drinking and cultural water use (MPC) is the concentration of a harmful substance in water, which should not have a direct or indirect effect on the human body throughout his life and on the health of subsequent generations, and not should worsen the hygienic conditions of water use. The maximum permissible concentration in the water of a reservoir used for fishing purposes (MPC VR) is the concentration of a harmful substance in the water, which should not have a harmful effect on fish populations, primarily commercial ones. Water quality regulation consists of establishing for the water of a water body a set of acceptable values for indicators of its composition and properties, within which the health of the population, favorable conditions for water use and the environmental well-being of the water body are reliably ensured. Security rules surface waters establish standards for the water quality of reservoirs and watercourses for the conditions of economic and drinking, cultural, domestic and fishery water use. A substance that causes a violation of water quality standards is called a pollutant.
Types of water use
Types of water use at water bodies are determined by the bodies of the Ministry natural resources of the Russian Federation and the State Committee of the Russian Federation for Protection environment and are subject to approval by local government bodies of the constituent entities of the Russian Federation.
Household and drinking water use includes the use of water bodies or their sections as sources of household and drinking water supply, as well as for supplying food industry enterprises. In accordance with Sanitary Rules and Standards SanPiN 2.1.4.559-96, drinking water must be safe in terms of epidemics and radiation, harmless in chemical composition and must have favorable organoleptic properties.
Cultural and domestic water use includes the use of water bodies for swimming, sports and recreation of the population. Water quality requirements established for cultural and domestic water use apply to all areas of water bodies located within populated areas, regardless of the type of their use by objects for habitat, reproduction and migration of fish and other aquatic organisms. Fishing water bodies can fall into one of three categories:
· the highest category includes locations of spawning grounds, mass feeding grounds and wintering pits, especially valuable species fish and other commercial aquatic organisms, as well as protected zones of farms of any type for breeding and growing fish, other aquatic animals and plants;
The maximum permissible concentration of a substance in water is established:
· for household, drinking and cultural and domestic water use (MPC v) taking into account three hazard indicators:
· organoleptic;
general sanitary;
· sanitary-toxicological.
· For fishery water use (MPC vr), taking into account five hazard indicators:
· organoleptic;
· sanitary;
· sanitary-toxicological;
· toxicological;
· fishery.
The organoleptic hazard indicator characterizes the ability of a substance to change the organoleptic properties of water. General sanitary - determines the influence of a substance on the processes of natural self-purification of water due to biochemical and chemical reactions with the participation of natural microflora. The sanitary-toxicological indicator characterizes harmful effects on the human body, and toxicological - shows the toxicity of a substance for living organisms inhabiting a water body. The fishery indicator of harmfulness determines the deterioration of the quality of commercial fish.
The lowest of the harmless concentrations for three (five) hazard indicators is taken as the MPC with an indication of the limiting hazard indicator. Fishery MPCs must satisfy a number of conditions under which they should not be observed:
· death of fish and food organisms for fish;
· gradual disappearance of fish species and food organisms;
· deterioration in the commercial quality of fish living in a water body;
· replacement of valuable fish species with low-value ones.
The quality of natural waters is influenced by natural and anthropogenic factors.
The formation of the chemical composition of natural waters is determined mainly by two groups of factors:
· direct factors that directly affect water (i.e., the action of substances that can enrich water with dissolved compounds or, conversely, release them from water): composition rocks, alive organisms, economic activity person;
· indirect factors that determine the conditions under which the interaction of substances with water occurs: climate, topography, hydrological regime, vegetation, hydrogeological and hydrodynamic conditions, etc.
Table 1. Factors in the formation of the chemical composition of natural waters
|
Formation factors and results of their influence |
Types of natural waters |
||
|
Atmospheric precipitation (rain, snow, frost, hail) |
Land surface waters (rivers, streams, lakes, swamps) |
The groundwater |
|
|
Direct formation factors |
soils, rocks, plants, salts from salt marshes, salts from the surface of ice, human activity, cosmic dust, discharge of atmospheric electricity (nitrogen oxides), volcanic gases, dust |
precipitation, soils, rocks, plants, groundwater, wastewater (industrial, agricultural, domestic) |
surface waters, soils, rocks, physical and chemical processes (dissolution-sedimentation, sorption-desorption, etc.) |
|
Results of the influence of direct factors on the composition of water |
transition to the soluble state of salts: entry into the atmosphere and formation of solid and liquid aerosols and gases in it |
entry of chemicals into various forms: suspended, colloidal, dissolved (ions, complex compounds, undissociated compounds) |
entry of chemicals in dissolved form, precipitation as a result of physical and chemical processes |
|
Indirect formation factors |
climate, relief, vegetation, water regime |
climate, relief, geological conditions, burial depth, temperature and pressure |
|
|
The result of the influence of indirect factors on the composition of water |
enrichment of atmospheric precipitation with chemicals in various concentrations depending on climatic conditions and intensity of anthropogenic impact in the region |
differentiation of the entry of chemicals into surface waters in space (geographical, climatic zonation) and in time (hydrochemical regime) |
change in the chemical composition of water by concentration (mineralization) and ratio of components (relative composition) |
Based on the nature of their impact, the factors that determine the formation of the chemical composition of natural waters can be divided into the following groups:
· physical and geographical (relief, climate, weathering, soil cover);
· geological (rock composition, tectonic structure, hydrogeological conditions);
physico-chemical ( Chemical properties elements, acid-base and redox conditions, water mixing and cation exchange);
· biological (activity of plants and living organisms);
· anthropogenic (all factors associated with human activity).
Classification of waters according to integral quality indicators
The category of the most commonly used indicators for assessing the quality of water bodies includes hydrochemical index of water pollution WPI and hydrobiological index of saprobity S.
The water pollution index is usually calculated using six to seven indicators that can be considered hydrochemical; Some of them (dissolved oxygen concentration, pH value, biological oxygen demand BOD 5) are mandatory.
C i is the concentration of the component (in some cases, the value of the parameter);
N is the number of indicators used to calculate the index;
MPC i is the established value for the corresponding type of water body.
Depending on the value of WPI, areas of water bodies are divided into classes (Table 1). Water pollution indices are compared for water bodies of one biogeochemical province and similar type, for the same watercourse (downstream, in time, and so on).
Table 2. Water quality classes depending on the value of the pollution index
|
WPI values |
Water quality classes |
|
|
Very clean |
||
|
Moderately polluted |
||
|
Contaminated |
||
|
Very dirty |
||
|
Extremely dirty |
Of the hydrobiological quality indicators in Russia, the most widely used is the so-called saprobity index of water bodies, which is calculated based on the individual characteristics of the saprobity of species represented in various aquatic communities (phytoplankton, periphyton):
where S i is the saprobity value of the aquatic organism, which is specified in special tables;
h i - relative occurrence of indicator organisms (in the field of view of the microscope);
N is the number of selected indicator organisms.
Each type of organism under study is assigned a certain conditional numerical value of the individual saprobity index, reflecting the totality of its physiological and biochemical properties that determine the ability to live in water with a particular content organic matter. For statistical reliability of the results, it is necessary that the sample contains at least twelve indicator organisms with a total number of individuals in the observation field of at least thirty.
In table Figure 3 shows the classification of water bodies according to the value of the saprobity index S, which are also standardized.
Table 3. Water quality classes depending on saprobity indices
The water pollution index and the saprobity index should be considered integral characteristics of the condition. The level of pollution and quality class of water bodies are sometimes set depending on microbiological indicators (Table 4).
Table 4. Water quality classes according to microbiological indicators
|
Pollution level and water quality class |
microbiological indicators |
||
|
Total number of bacteria, 10 6 cells/ml |
Number of saprophytic bacteria, 1000 cells/ml |
Attitude total number bacteria to the number of saprophytic bacteria |
|
|
Very clean, I |
|||
|
Clean, II |
|||
|
Moderately polluted, III |
|||
|
Contaminated, IV |
|||
|
Dirty, V |
|||
|
Very dirty, VI |
Currently in Russia there are two MPC systems - sanitary and hygienic, focused on human health, and fishery, focused on safety for fish as the highest trophic level of a water body (i.e. it is implicitly assumed that if safety for fish is ensured, then automatically it is also safe for other aquatic organisms). Maximum permissible concentrations were developed (and are being developed) by health authorities (specifically, sanitary and hygienic authorities) and express the threshold value of the concentration of chemicals and microorganisms in the water of a water body, the consumption of which (water) throughout life is safe for human health.
Maximum permissible concentrations for fisheries are developed by scientific organizations in the fisheries industry and also fix the level of concentration that is safe for fish (which species are not specified).
To domestic and drinking water use (MPC) V ) This includes the use of water bodies or their sections as sources of domestic and drinking water supply, as well as for supplying food industry enterprises. In accordance with SanPiN 2.1.4.1074-01, drinking water must be safe in terms of epidemics and radiation, harmless in chemical composition and must have favorable organoleptic properties.
To municipal and domestic water use (MPC) V ) includes the use of water bodies for swimming, sports and recreation of the population. The water quality requirements established for cultural and domestic water use apply to all areas of water bodies located within populated areas, regardless of the type of their use by objects for the habitat, reproduction and migration of fish and other aquatic organisms.
For fishery use (maximum permissible concentration px ) of a water body, the inhabitants of water bodies are used for the habitat, reproduction and migration of fish and other aquatic organisms, and therefore the requirements for the content of pollutants are higher. More stringent regulation of water quality in fishery water bodies is associated with the cumulative effect of pollutants in aquatic organisms.
To date, the Russian Federation has established maximum permissible concentrations in natural waters for more than 800 chemicals. Requirements for water quality in reservoirs used for fishing purposes are specific and in most cases more stringent than for water bodies for domestic purposes. Thus, fishery MPCs for a number of detergents are three times lower than household and drinking water standards, oil products - six times, and heavy metals (zinc) even one hundred times. This difference in standards is explained by the biological accumulation of up to life-threatening quantities of harmful substances during their passage through the food (trophic) chain.
For water bodies, simultaneously with the MPC, another restrictive standard is used - limiting hazard index (LPI) a substance that does not have a quantitative characteristic, but reflects the priority of water quality requirements. The essence of the LPV is that water pollutants can have adverse effects on aquatic ecosystems and human health according to classified effects, each of which is characterized by its own safe concentration. That of the influences, the safe concentration of which is minimal compared to other influences, is established as the limiting indicator of the harmfulness of the substance.
Requirements for the protection of surface waters distinguish the following types of wetlands:
organoleptic LPV , changing the organoleptic properties of water (the organoleptic properties of water are a set of water quality indicators perceived by human receptors: smell, taste, color, transparency (turbidity), the presence of films or foam on the surface of the water, foreign inclusions, floating impurities, sediment);
general sanitary LPV – determines the influence of a substance on the processes of natural self-purification of water due to biochemical and chemical reactions with the participation of natural microflora;
sanitary-toxicological indicator characterizes the harmful effects on the human body;
toxicological LPV , characterizing the toxic effect of a substance on the human body and animals living in water.
fishery indicator harmfulness determines the deterioration of the quality of commercial fish.
For pollutants contained in a water body, the following conditions must be met:
C i ≤MPC i
Where WITH i – average annual concentration in water i-th substance; MPC i – maximum permissible concentration of a pollutant.
If there are several substances belonging to the same group of the limiting hazard indicator, the content of the pollutant must comply with the condition
Where m– the total amount of substances of this group of liquid substances present in the water of the studied object.
For a comprehensive assessment of the quality of surface and sea waters The water pollution index (WPI) is used, which is calculated as the sum of the actual values of quality indicators for 6 main water pollutants reduced to the maximum permissible concentration:
where 6 is the limited number of indicators used for calculation.
Maximum permissible discharge - this is the maximum amount of pollutants that a given specific enterprise is allowed to discharge into a body of water per unit of time, without causing them to exceed the maximum permissible concentrations and adverse environmental consequences.
According to Art. 23 of the Federal Law (On Environmental Protection of 2002), if it is impossible to comply with VAT, which is practically the case everywhere, limits may be set on discharges of pollutants. And they are established on the basis of permits that are valid only during the period of environmental protection measures, the introduction of NST and (or) the implementation of other environmental projects, taking into account the gradual achievement of the established VAT. Establishing limits on discharges is allowed only if there are plans to reduce discharges, agreed upon with the executive authorities exercising public administration in the field of environmental protection.
One of the tasks of environmental monitoring is to assess the degree of pollution of water bodies. Moreover, all water quality indicators can be divided into three groups: hydrochemical, hydrological and hydrobiological.
Within state monitoring water bodies rationing is used:
To set water use limits;
for the development and adoption of regulations, standards and rules in the use and protection of water bodies.
In order to protect water bodies from pollution, maximum permissible concentrations (MAC) of substances that worsen water quality have been developed. Water quality refers to the characteristics of its composition and properties, which determine its suitability for specific types of water use. Quality criteria are signs by which water quality is assessed.
The rules for the protection of surface waters determine the water quality standards of watercourses and reservoirs for domestic, drinking, cultural, domestic and fishery water use.
Household and drinking water use involves the use of water bodies as sources of household and drinking water supply for the population and food industry enterprises. In accordance with the “Sanitary Rules and Standards (SanPiN 2.1.4.559–96)”, drinking water must be safe in terms of epidemics and radiation, harmless in chemical composition and must have favorable organoleptic properties.
Cultural and domestic water use refers to the use of water bodies for swimming, recreation and sports. Water quality requirements for this type of water use apply to all water bodies located within populated areas.
In the Russian Federation, fishery water bodies can fall into three categories:
The highest category includes places of spawning grounds, mass feeding and wintering of valuable fish species, as well as protected zones of farms engaged in breeding and raising fish and other aquatic animals;
The maximum permissible concentration of pollutants in water bodies for domestic, drinking and cultural purposes (MPC) is the concentration of a substance in water, which should not have a direct or indirect effect on the human body throughout life. It should also not impair the hygienic properties of water.
The maximum permissible concentration of harmful substances in fishery reservoirs (MPCv) is the concentration of pollutants in water that should not have a harmful effect on commercial fish.
MPC in reservoirs is established for different types of water use according to several indicators.
MAC for household, drinking and cultural and domestic water use is determined by three hazard indicators:
Organoleptic;
general sanitary;
sanitary-toxicological.
For fishery water use (MPCvr) is established taking into account the following indicators:
Organoleptic;
sanitary;
sanitary-toxicological;
toxicological;
fishery
The organoleptic indicator gives an idea of changes in the organoleptic properties of water.
General sanitary shows the impact of substances on the processes of natural self-purification of a reservoir based on chemical and biochemical processes with the participation of microorganisms.
The sanitary-toxicological indicator indicates the harmful effects of a substance on the human body, and the toxicological indicator characterizes the toxicity of a substance to living organisms.
The fishery indicator determines the deterioration in the quality of commercial fish.
In addition to standards for impact factors, there are standards for sources of impact. Until recently, the concept of maximum permissible discharge (MPD) was widely used - the mass of a substance in wastewater, the maximum permissible for discharge with the established regime at a given point of a water body per unit of time in order to ensure water quality standards at the control point. The value of this indicator was established based on the conditions of not exceeding the maximum permissible concentrations of harmful substances (MPC) at the control site or at a section of the water body, taking into account its intended use, and if the MPC was exceeded at the control site, from the condition of maintaining (non-deterioration) the composition and properties of water in water bodies formed under the influence of natural factors.
In 2007, by order of the Ministry of Natural Resources, a new methodology was approved for developing standards for permissible discharges of substances and microorganisms into water bodies for water users, according to which, together with the MAP, the concept of normatively permissible discharge (VAT) is introduced.
Hydrological indicators of pollution of aquatic ecosystems include:
Size absolute indicator total load at given guaranteed water flows in the river;
Indicator of excess pollution above the norm;
Indicator of pollution not exceeding the norm;
An indicator relative to the load of a stream by a pollutant.
Hydrobiological integral indicators for assessing water quality have become widespread. The classic system for biological analysis of water quality was developed by biologists R. Kolkwitz and M. Marsson back in 1902.
Thus, the assessment of water quality is based on a comparison of the results of the analysis of the chemical composition, physical properties, hydro- and microbiological characteristics of water at individual points of the reservoir with the corresponding standard indicators of its quality.
Reviews
I look at the modern “Yearbooks on the quality of surface waters of the Russian Federation”.
Well, what fool came up with this form of presenting material?
A rare profanity. Or it was done on purpose to make the user uncomfortable.
Do you know who designed this Yearbook layout?
The latest method for comprehensive assessment of water quality (combinatorial index and other crap) also differs for the worse from WPI.
Water quality standards for water bodies include: general requirements for the composition and properties of water in watercourses and reservoirs for various types water use; · a list of maximum permissible concentrations of standardized substances in the water of water bodies used for household, drinking and municipal needs of the population; · a list of maximum permissible concentrations of standardized substances in the water of water bodies used for fishing purposes.
For all regulated substances for fishery water use and for substances belonging to hazard classes 1 and 2 for other types of water use, when several substances with the same limiting sign of harmfulness enter water bodies, the sum of the concentration ratios (Ci, C2, ..., Cn) of each substance at the control site to the corresponding MPC should not exceed one.
For unique water bodies, special water quality requirements may be established. So water bodies may be given the status of a reserve or wildlife sanctuary in accordance with the procedure established by law.
Noise regulation
Noise has Negative influence for the entire human body. Moderate noise levels (less than 80 dBA) do not cause hearing loss, but nevertheless have a tiring adverse effect, which is combined with similar effects of other harmful factors and depends on the type and nature of the work load on the body.
Noise regulation is intended to prevent hearing impairment and a decrease in the working capacity and productivity of workers.
For different types Various methods of normalization are used for noise.
For constant noise levels sound pressure levels are normalized L Pi(dB) in octave bands with geometric mean frequencies 63, 125, 250, 500, 1000, 2000, 4000, 8000 Hz. For an approximate assessment of the noise characteristics of workplaces, it is allowed to take the sound level as the noise characteristics L in dB(A), measured according to the time characteristic of the sound level meter “S - slow”.
The normalized parameters of intermittent and impulse noise at design points should be considered equivalent (but energy) sound pressure levels L eq in dB in octave frequency bands with geometric mean frequencies 63, 125, 500, 1000, 2000, 4000 and 8000 Hz.
For For non-constant noise, the equivalent sound level in dB(A) is also standardized.
Permissible sound pressure levels for workplaces in office premises and for residential and public buildings and their territories are different.
The regulatory document regulating noise levels for various categories of workplaces in office premises is GOST 12.1.003-83 “SSBT. Noise. General requirements security."
Permissible sound pressure levels (equivalent sound pressure levels) in dB in octave frequency bands, sound levels and equivalent sound levels in dBA for residential and public buildings and their territories should be taken in accordance with SNiP 11-12-88 “Noise Protection”.