Detailed Assessment

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5.2. Detailed Assessment

5.2.1. Introduction

The category “Pollution Control” includes three subcategories:

1.        Overall Performance;

2.        Wastwater Characteristics;

3.        Wastwater Loadings.

The subcategory “Overall Performance” includes 10 indices:

1. Normal general disposal rate

2. The share of effluents

3. Dilution / mixing

4. Secondary pollutants

5. Method of discharge

6. Frequency of discharge

7. Frequency of monitoring of discharge

8. Frequency of tests and analysis

9. Type of sampling

10. Control of the flow of discharge

11. The subcategory “Pollutant load” includes 22 indices, the same as those included in the subcategory “Wastwater characteristics”.

12. BOD₅

13. COD

14. Total Suspended Solids

15. Total Dissolved Solids

16. Phosphorus

17. Аmmonia nitrogen

18. Nitrate nitrogen

19. Nitrite nitrogen

20. Oil products

21. Persistent Organic Pollutants

22. Phenols

23. Polyaromatic Hydrocarbons

24. Oils and fats

25. Iron

26. Copper

27. Zinc

28. Nickel

29. Chromium

30. Cadmium

31. Mercury

32. Lead

33. Radioisotopes

The discharges from communal wastewater treatment facilities as a rule have a higher volume than discharges from industrial complexes.  Therefore, two sets of data were proposed for the criteria “Normal general disposal rate”: one for communal wastewater treatment facilities, the second for industrial complexes.  The assessment of hot spots, which do not fall under any of above-mentioned categories, was based on the data reasoning from characteristics of the discharge (for example, in order to carry out an assessment of storm precipitation, snowmelt runoff, or agricultural wastewater, it would be better to use data of the assessment of communal wastewater treatment facilities).

5.2.2. Wastewater Treatment and Effluent Discharge

5.2.2.1. Normal General Disposal Rate

Communal discharges: The effluent discharges from communal wastewater treatment facilities are as a rule of greater volume than discharges from industrial enterprises. Accordingly, we increased the average rate of discharge based on the conclusions made by the experts.  The rates of discharges are fixed at the level of 1000 m³ per day.

Industrial discharges: This criterion enables a differentiation between industrial enterprises of the same sector subject to the size of the enterprise.  As a rule, the volume of the resulting wastewater is proportionate to the volume of production.  It is considered that big enterprises are those where the volume of discharge exceeds 2500 m³ per day, medium enterprises are those where the volume of discharge is above 1000 m³ per day, and small enterprises are below 50 m³ per day.

At present, only three among the 15 enterprises included in the refined preliminary list are industrial enterprises.  These are: PA “Khimvolokno” of the Town of Svetlogorsk, the Svetlogorsk heat station, and JSC “Mozyrsky petroleum refinery”. In 2000, the volume of industrial discharge of these enterprises made up 75, 15, and 53 thousand m³ per day respectively.  At the same time, it should be noted that wastewater treatment facilities of the Mozyrsky petroleum refinery are also used for the treatment of municipal discharges of the towns of Mozyr and Kalinkovichi.  Hence, the value of index 1.1b for these enterprises was qualified as 5 points (Annex B, Table B1).

Wastewater treatment facilities of Mogilev PA “Khimvolokno” and “Retchitsa experimental-industrial hydrolytic plant” also provided treatment of municipal discharges of the towns of Mogilev and Retchitsa and at present they are placed under the jurisdiction of Vodokanals of these towns.  The total average daily discharge made up 171 and 25 thousand m³.  For the scoring sheets, the enterprises were qualified as 5 and 3 points respectively (see Table 5.1).  The volume of average daily discharge of municipal treatment facilities of the cities of Minsk, Gomel, Bobruisk, Bereza, Borisov, Orsha, Pinsk, Soligorsk, Slutsk and Zhlobin amounted to 671, 153, 121, 106, 59, 48, 37, 36, 26, and 21 thousand m³ respectively.  According to index 1.1a for pollution control in the scoring sheet, the sites were given scores of 5, 5, 5, 5, 4, 3, 3, 3, 3 and 3 respectively (see Annex B, Table B1).

5.2.2.2. The Share of Treated Effluents

This criterion was applied for the assessment of both continuous and periodic effluent discharges.  In spite of the fact that continuous discharges are subject to treatment, the spill wastewater can fall into a water body untreated and this entails serious negative consequences. For example, such a situation is quite possible in the metalworking industry, where industrial wastes are subject to treatment and discharges from sludge pits are not.

Practically at all enterprises, everyday effluent discharges are subject to treatment with the exception of the Svetlogorsk heat station (only 18% of wastewater undergo treatment there), “Gomelvodokanal” (88.5%) and Mogilev Vodokanal (96.4%).  Therefore, the values of index 1.2 are as follows: Svetlogorsk heat station – 5; “Gomelvodokanal” and Mogilev Vodokanal – 1, for the other enterprises – 0 (Annex B, Table B2).

5.2.2.3. Dilution / Mixing

In order to take into proper account the ability of rivers to assimilate contaminants, the experts compared the hydraulic disposal rate in m³ per day and river flow.  For this purpose it is necessary to determine the coefficient of mixture and dilution ratio – the ratio of the volume of river run-off to the volume of discharge.  The river run-off of summer-and-autumn mean water of the year (95% of supply) was used as the standard value of river run-off.

Data concerning river stations in the localities of discharge of industrial effluents from wastewater treatment facilities are given in Table 5.1.

Table 5.1 : Annual Mean Flow

 

The lowest coefficients for the dilution of river flow are typical for the cities of Soligorsk and Minsk.  The volume of discharge of the Minsk wastewater treatment plant is almost comparable with the river flow of summer and autumn mean flow; the coefficient of dilution is 1.2.  Discharge of treated municipal effluent of the town of Soligorsk takes place to the ditch, which flows into the Morotch River.  The volume of discharge exceeds the Morotch River run-off of summer-and-autumn mean water and the coefficient of dilution is equal to 0.6.  Therefore in relation to index 1.3, these enterprises are assigned the highest score, 5 (Annex B, Table B3).

Low values of dilution coefficients are typical for wastewater treatment facilities of the cities of Bereza and Slutsk – 4.3 and 5.5, that corresponds to a value of 5 and 4 points (Annex B, Table B3).

Average values of dilution coefficient are typical for the wastewater treatment facilities of the cities of Mogilev, Borisov, Gomel, and the Svetlogorsk heat station. The values respectively are: 23, 24, 30 and 40, therefore these enterprises are qualified as 2 points (Annex B, Table B3).

High values are observed in effluent discharges in the cities of Bobruisk, Orsha and PA “Khimvolokno” of the town of Svetlogorsk – 42, 70, 80, therefore, in this particular case the score is equal 1 (Annex B, Table B3).

The highest values of dilution coefficient are registered in the discharge of treated effluent from wastewater treatment facilities of Pinsk City, “Mozyrsky petroleum refinery”, wastewater treatment facilities of the cities of Zhlobin and Retchitsa, they made up 97, 142, 274 and 525 respectively.  The value of index for these enterprises was qualified as 0 (Annex B, Table B3).

5.2.2.4. Secondary Pollutants

Pollutants incoming from secondary sources both to communal waster water treatment facilities and industrial treatment works can seriously affect the quality of discharges.  Industrial enterprises do not control pollution incoming from secondary sources as strictly as their own pollution.  Therefore, there is a certain uncertainty in relation to the quality of discharge and consequently there is a serious danger of negative impact of discharges.  In the case of communal wastewater treatment facilities, the greater the share of wastewater received from industrial enterprises, the higher the probability that the discharge will contain such pollutants as heavy metals and oil products.

Regarding communal effluent treatment plants, the highest share of daily discharge from enterprises is observed in the towns of Mogilev, Bobruisk, Orsha, of 50, 60 and 45% respectively, therefore, for index 1.4a they are given a score equal to 5.  The share of discharges coming from enterprises to wastewater treatment facilities of the towns of Retchitsa, Borisov and Bereza (around 33%) is high; it corresponds to a score of 4.  The medium values of the share of industrial discharges to wastewater treatment facilities of the towns of Zhlobin and Slutsk are equal 30 and 26%, and correspond to a score of 3.  Low values of the share of industrial enterprises in effluent discharge are observed at wastewater treatment facilities of the cities of Gomel and Pinsk – around 11%, that correspond to a score of 2.  The lowest values of the share of industrial enterprises in effluent discharge are registered at wastewater treatment facilities of the cities of Minsk and Soligorsk – 7 and 6%.  Hence, the value of index 1.4a was qualified as 1 (Annex B, Table B4).

At Svetlogorsk “Khimvolokno” and “Mozyrsky petroleum refinery”, the share of communal enterprises in the sewers for industrial enterprises makes up 60 and 55%, consequently according to index 1.4b the score for these enterprises is 5.  The share of communal discharges at wastewater treatment facilities of Svetlogorsk heat station comes practically to 10%, that correspond to a value of 1 (Annex B, Table B4).

5.2.2.5. Method of Discharge

The method of discharge of treated and untreated wastewater has an influence on the location and the size of the mixing zone, where toxic conditions can be created.  Unregulated industrial discharges are those discharges where there is no definite point of discharge and it is impossible to carry out a test.  This category includes situations when it is impossible to determine availability of manifold pipes / sewers or in the case of overland discharges.

Underground discharges are considered undesirable irrespective of whether they are controlled or not, as they represent the threat of pollution of underground water used by many inhabited localities for drinking water supply.

The method of discharge of treated effluent used at wastewater treatment facilities of the cities of Minsk, Retchitsa, Gomel, Borisov, Bobruisk, Bereza, Pinsk, Zhlobin, Soligorsk, Slutsk as well as at wastewater treatment facilities of Svetlogorsk PA “Khimvolokno” and Svetlogorsk heat station is single superficial water outlet, therefore the value of index 1.5 for these enterprises was qualified as 5 points (Annex B, Table B5).

The method of discharge used at wastewater treatment facilities of the cities of Mogilev and Orsha is a submerged outlet, that corresponds with a value of 2 points in the scoring sheet (Annex B, Table B5).

The method of discharge used at the wastewater treatment facilities of Mogilev City and Mozyrsky refinery is a submerged dispersive outlet, therefore, the score is equal to 1 (Annex B, Table B5).

5.2.2.6. Frequency of Discharge

It is acknowledged that periodic discharges have less influence upon the environment than continuous discharges as there is no deterioration of water in the intervals between the discharges.  Nevertheless, periodic discharges cause serious damage to fish and other living organisms.  Water inhabitants, which can find themselves in the area of discharge at the moment when it takes place, therefore experience the consequences of prompt deterioration of water quality.  Mobile living organisms usually avoid the areas of mixing of continuous discharges.

Continuous discharge is typical for all the 15 enterprises, therefore, the value of index 1.b was qualified in the pollution control scoring sheet as 5 points for all enterprises (Annex B, Table B6).

5.2.2.7. Frequency of Tests and Analysis

It is acknowledged that frequent and regular monitoring of discharges ensures better or potentially better ecological management and control.

As a rule, continuous monitoring of discharges is preferable as compared with periodical monitoring, as continuous monitoring may detect unregulated discharges and possibly obtain control of them.  Nevertheless, in the cases when the flow of discharges is constant, periodic monitoring of water flow is quite possible.

Monitoring of discharge takes place continuously (in individual points of discharge) at wastewater treatment facilities of the cities of Minsk, Retchitsa and Orsha.  Therefore the value of index 1.7 is scored as 2 (Table 5.2.8).  Monitoring of discharge takes place periodically in many points of discharge at wastewater treatment facilities of the cities of Mogilev, Borisov, Bobruisk, Zhlobin as well as at wastewater treatment facilities of the enterprises “Mozyrsky NPZ” and Svetlogorsk “Khimvolokno”, this corresponds with a value of 3 points in the scoring sheet (Annex B, Table B7).

Monitoring of discharge takes place periodically (in individual points of discharge) at wastewater treatment facilities of the cities of Gomel, Bereza, Pinsk, Slutsk, Soligorsk, and at the Svetlogorsk heat station.  This corresponds with a value of 4 points (see (Annex B, Table B7).

5.2.2.8. Place of Sampling

Sampling takes place at all points of discharge at “Mozyrsky petroleum refinery”, Zhlobinsky, Borisovsky, Retchitsky vodokanals, as well as at the enterprise Svetlogorsk “Khimvolokno”.  For these enterprises the value of index 1.8 is 0 (Annex B, Table B8). At the vodokanals of the cities of Mogilev, Bobruisk, Bereza, at Svetlogorsk PA “Khimvolokno”, the sampling is carried out at individual points of discharge.  These enterprises were given a score of 2 (Annex B, Table B8).  The value of index 1.8 at these enterprises is assumed as equal to 0 (Annex B, Table B8). At Orsha, Soligorsk and Slutsk vodokanals the sampling takes place at individual points of discharge.  Here the value of the score is equal to 3 (Annex B, Table B8).

At vodokanals of the cities of Minsk, Gomel, Pinsk, and at the Svetlogorsk heat station the sampling is conducted at one point of discharge.  The value of index 1.8 was qualified as 4 points (Annex B, Table B8).

5.2.2.9. Type of Sampling

In order to identify periodic changes in water flow composition it is better to carry out continuous complex sampling rather than to undertake intermittent sampling. However, in terms of monitoring of river flow, continuous complex sampling and intermittent sampling of discharges that have constant composition (as identified in initial continual sampling and confirmed by continual sampling periodically carried out) are equivalent.

Sampling and analysis are carried out constantly at wastewater treatment facilities of Retchitsa Vodokanal, which corresponds to a score of 1. Daily sampling and analysis takes place at wastewater treatment facilities of the cities of Minsk, Gomel, Borisov, Mozyr, Orsha, Zhlobin, Soligorsk, Mogilev, Slutsk and at Soligoesk PA “Khimvolokno”.  The value of index 1.9 for these enterprises in the scoring sheets is taken as a score equal to 2.  Weekly sampling and analysis are carried out at vodokanals of the cities of Minsk, Retchitsa, Mogilev, Bobruisk, Bereza and at Svetlogorsk heat station.  The value of the index for these enterprises is taken as equal to 3. Monthly sampling and analysis takes place at wastewater treatment facilities of Bobruisk vodokanal. The value of index 1.9 is qualified as 4 points (Annex B, Table B9).

5.2.2.10. Control of the Flow of Discharge

Lack of control of the flow of discharge takes place at wastewater treatment facilities of the cities of Gomel, Borisov, Soligorsk, Bereza and at Svetlogorsk heat station.  The value of index 1.10 for these enterprises is taken as equal to 5.  Several tests at individual points of discharge are conducted at wastewater treatment facilities of the cities of Retchitsa, Gomel, Slutsk, at Svetlogorsk PA “Khimvolokno” and “Mozyrsky petroleum refinery”.  The value of index 1.10 for these enterprises is qualified as 3 points.  Several tests at all points of discharge takes place at Orsha and Pinsk vodokanals.  These enterprises were assigned a score of 1.  All points of discharge are under control at wastewater treatment facilities of the cities of Retchtsa, Minsk, Mogilev, Bobruisk, Zhlobin.  The value of index 1.10 was qualified as 0 for the scoring sheets (Annex B, Table B10).

5.2.3. Wastwater Characteristics

The main data characterizing concentration of actual effluent discharges for the year 2000 are given in Annex 1.  Ranking of the degree of impact upon the environment is based on six categories.  They are as follows:

0        no impact

1        minor impact

2        moderate impact

3        strong / large-scale impact

4        adverse impact

5        extremely heavy impact

5.2.3.1. Substances Consuming Oxygen or Exhausting Oxygen Content

In certain sectors of industry, such as the production of agricultural commodities and especially when treatment of wastewater is not undertaken, the concentrations of BOD and COP are very high.

The highest values of BOD₅ are observed in effluent discharge from wastewater treatment facilities of the cities of Retchitsa and Bereza – 132 and 91 mg/l respectively.  In conformity with the limits assigned, the values of index 2.1a are qualified as 4 and 3 points (Annex B, Table B11).

Concentrations in discharge at wastewater treatment facilities of the other enterprises do not exceed 15 mg/l, therefore the value of the index is 0 (Annex B, Table B11).  The highest values of COP are also typical for Retchitsa vodokanal and Berezovsky vodokanal, they make up 232 and 342 mg/l, that correspond with a value of 4 and 5 points for index 2.2a (Annex B, Table B12).  Medium values are typical for discharge from wastewater treatment facilities of the cities of Minsk, Gomel, Borisov, Soligorsk, as well as for “Mozarsky petroleum refinery” and Svetlogorsk heat station. They are within the limits of 50-96 mg/l that correspond to a score of 2.  The value of COP for Bobruisk city is somewhat higher – 100 mg/l, therefore, in this case the value was qualified as 3 points.

Low values of COP are observed in discharge from wastewater treatment facilities of the cities of Mogilev, Orsha, Pinsk, Zhlobin and Slutsk – within the limits of 20-31 mg/l.  The value of index 2.2a is taken therefore as 1.  The lowest values of COP are registered at Svetlogorsk “Khimvolokno” and Svetlogorsk heat station – 11 mg/l, that correspond with a value of 0 in the scoring sheet (Annex B, Table B12).

5.2.3.2. Total Suspended Solids (TSS)

Suspended solids affect water clarity, they can constitute bottom sediments that are able to move downstream.  Suspended solids, which contain toxic organic matters, heavy metals, etc., were evaluated according to their specific criteria.

The highest concentration of suspended solids (TSS) is observed in effluent discharged from the wastewater treatment facilities of the town of Retchitsa, it makes up 138 mg/l.  The value of index 2.3a is therefore qualified as 4 points.  A medium content of suspended solids in the discharged effluent is typical for Berezovsky vodokanal – 65 mg/l (the score is equal to 3).  A low content is measured in discharged effluent from wastewater treatment facilities of Minskvodokanal, “Mozyrsky NPZ”, Mogilevsky vodolanal – 20-25 mg/l (the value of index is qualified as 1 point).  The lowest values of TSS are registered in the discharged effluent from wastewater treatment facilities of the cities of Borisov, Bobruisk, from Soligorsk “Khimvolokno”, Soligorsk heat station, from vodokanals of the cities of Orsha, Pinsk, Zhlobin, Slutsk and Soligorsk – within the limits of 0.6-12 mg/l.  The index value for these enterprises was qualified as 0 (Annex B, Table B13).

5.2.3.3. Total Dissolved Solids (TDS)

The highest values of total dissolved solids in discharged effluent were observed at wastewater treatment facilities of “Retchitsa vodokanal” and Svetlogorsk “Khimvilikno” – 1162 and 1116 mg/l.  The value of index 2.4a for these enterprises is qualified as 5 points (Annex B, Table B14).

Medium values were observed at wastewater treatment facilities of the cities of Orsha, Slutsk, Soligorsk– 702, 737, 732 and 610 mg/l respectively, that correspond to a value of 3 and 2 points in the scoring sheet and that correspond to Bobruisk (610 mg/l) (Annex B, Table B14).

Low values of total dissolved solids are typical for effluent discharge from wastewater treatment facilities of the cities of Mogilev and Zhlobin – 591 and 566 mg/l (the value of index was qualified as 1 point).

The lowest values of total dissolved solids were registered in discharged effluent from wastewater treatment facilities of “Mozyrsky petroleum refinery”, Berezovsk vodokanal, Minsk effluent treatment plant, vodokanals of the cities of Borisov, Gomel and Svetlogorsk heat station.  They made up 495, 490, 447, 438, 377 and 246 mg/l respectively.  For these enterprises the value of index 2.4a is qualified as 0 (Annex B, Table B14).

5.2.3.4. Total Phosphorus

The highest concentrations of total phosphorus were observed in the effluent discharged from wastewater treatment facilities of the cities of Retchitsa, Bereza, Borisov, Pinsk – 17.2; 83; 8.0 and 5.1 mg/l respectively.  The value of index 2.5a for these enterprises is qualified as 5 points.  High concentrations are also registered in effluent discharge of Minsk effluent treatment plant – 4.5 mg/l, that correspond to a value of 4 points (Annex B, Table B15).

A medium concentration is typical for the discharge from wastewater treatment facilities of the cities of Zhlobin, Bobruisk, Gomel – 3.7; 3.6; 3.3 mg/l respectively.  These enterprises are assigned a score of 3.  The cities of Soligorsk, Slutsk and “Mozyrsky petroleum refinery” have 2.4; 2.4 and 2.1 mg/l – corresponding to a score of 2.  A low content of phosphorus is observed in treated effluent of the town of Mogilev – 1.9 mg/l (the score is 1).

The lowest content of total phosphorus is typical for the discharge from wastewater treatment facilities of Svetlogorsk “Khimvolokno” and Svetlogorsk heat station – 0.7 and 0.3 mg/l respectively. The value of parameter 2.5a for these enterprises is qualified as 0 (Annex B, Table B15).

5.2.3.5. Ammonia Nitrogen (NH4-N)

The highest content of ammonia nitrogen is revealed in discharge from wastewater treatment facilities of the cities of Retchitsa, Bereza and Borisov – 86.9; 63.0 and 18.3 mg/l. Hence, the value of this index was qualified as 5 points (Annex B, Table B16).

A high content of ammonia nitrogen was observed in effluent discharge of Minsk effluent treatment plant, from wastewater treatment facilities of the cities of Mogilev and Pinsk – 14.6; 14.6; 13.8 mg/l.  The value of index 2.6a is qualified as 4 points.

Medium values are typical for Soligorsk, Slutsk and Bobruisk vodokanals – 11.3; 7.3 and 5.5 mg/l.  The values of index 2.6a for these enterprises were qualified as 3, 2 and 2 points.

A low content of ammonia nitrogen was observed in effluent discharge from wastewater treatment facilities of Gomelvodokanal, “Mozyrsky NPZ”, Zhlobin and Orsha vodokanals – 3.5; 3.0; 2.8 and 2.4 mg/l, that correspond to a value of 1 in the scoring sheet.

The lowest concentrations of ammonia nitrogen were registered at Svetlogorsk “Khimvolokno” and Svetlogorsk heat station – 1.0 and 0.7 mg/l.  The value of the index was qualified as 0 (Annex B, Table B16).

5.2.3.6. Nitrate Nitrogen (NO₃-N)

A low content of nitrate nitrogen (NO₃-N) in effluent discharge is typical for Byelorussian part of Dnipro basin.  The highest concentrations of nitrate nitrogen are observed in waste- water discharge from wastewater treatment facilities of “Mozyrsky petroleum refinery” – 12 mg/l, that corresponds to a score of 1 in the scoring sheet.  The other enterprises are characterized by even lower concentrations: from 6.4 mg/l (“Gomelvodokanal”) to 0.02 mg/l (Mogilev “Khimvolokno”).  The value of index 2.7a for these enterprises is qualified as 0 (Annex B, Table B17).

5.2.3.7. Nitrite Nitrogen (NO₂-N)

Concentrations of nitrite nitrogen are measured in a wide range.  Relatively high concentrations are observed in the discharge of Minsk effluent treatment plant and Slutsky vodokanal – 1.0 and 0.46 mg/l, therefore the score assigned is 5 and 4 respectively.

A medium concentration is observed in the discharge from wastewater treatment facilities of Soligorsk and Borisov vodokanals – 0.33 and 0.21 mg/l, the value of the index was qualified as 3 and 2 points accordingly.

Low concentrations are typical for effluent discharge from wastewater treatment facilities of the cities of Orsha, Gomel, Retchitsa, Pinsk, from “Mozyrsky NPZ” – 0.18; 0.15; 0.14;0.14 and 0.12 mg/l, respectively.  The value of index 2.8a for these enterprises is qualified as 1 point.

The lowest values of nitrite nitrogen concentrations are registered in discharge from wastewater treatment facilities of Mogilevsk “Khimvolokno”, Svetlogorsk “Khimvolokno”, Svetlogorsk heat station, Berezovsky, Zhlobinsky, Bobruisky vodokanals – 0.0; 0.009; 0.01; 0.018; 0.04 and 0.05 accordingly.  The value of the index for these enterprises is qualified as 0 (Annex D, Table D18).

5.2.3.8. Oil Products

The Byelorussian part of the Dnipro basin is characterized by a low content of oil products in effluent discharge from wastewater treatment facilities of the above-mentioned enterprises: from 0.08 (Svetlogorsk, Svetlogorsk heat station) to 0.66 mg/l (Berezovsky vodokanal).  Hence, the value of index 2.9a for all enterprises is qualified as 0 (Annex B, Table B19).

5.2.3.9. Persistent Organic Pollutants (POPs)

Persistent organic pollutants (POPs) are organic compounds incapable of quick biological decomposition in the natural environment, consequently they are accumulated in soil and aqueous medium.  This group includes some pesticides, herbicides, polychlorinated biphenyls, polyaromatic hydrocarbonates, halogen organic chemicals, etc.

The type, quantity or concentration of persistent organic pollutants contained in discharges depends upon the kind of industry.  Numerous compounds are identified already in small concentrations in many if not in all industrial discharges.  But in the case in question, the task is to determine discharges with comparatively high level of POPs concentration, which as expected is the consequence of the use of persistent organic pollutants as raw materials as well as consequence of formation of nonrecoverable or non-treated by-products.

In spite of the fact that this criteria includes all the identified persistent organic pollutants, information about the content of individual compounds in the discharges, as well as their concentration and load, can be useful in the assessment of the site.  In this way, more toxic persistent organic pollutants can be assigned a higher weighting factor.

The concentration of persistent organic pollutants in discharges of all enterprises in question was not measured and according to discharge characteristics most probably is not presented. Therefore the value of index 2.10б for all enterprises is qualified as 0 (Annex B, Table B20).

5.2.3.10.Phenols

The non-specific parameter of phenol concentration is convenient for primary wastewater analysis, especially of the enterprises of the petroleum industry and petrochemical industry. Phenols are also the indicators of pollution, effected by enterprises of organic chemistry as well as indicators of availability of other organic compounds in the water. Small concentrations of phenols give drinking water an unpleasant taste and smell.

Medium values of phenol concentrations are identified in effluent discharge from wastewater treatment facilities of “Retchitsa vodokanal”, Mogilevsky “Khimvolokno” and “Mozyrsky NPZ” and make up 0.054; 0.04 and 0.035 mg/l respectively.  The value of index 2.11a for these enterprises is qualified as 3,2 and 2 points.

Low values of phenol concentrations were observed in effluent discharge from wastewater treatment facilities of the town of Bobruisk – 0.005 mg/l.  The phenol content in effluent discharge of the other enterprises was not measured.  Therefore the value of index 2.11a is qualified as equal to 0 (Annex B, Table B21).

5.2.3.11. Polyaromatic Hydrocarbons (PAHs)

The concentration of polyaromatic hydrocarbons was not measured at the enterprises in question, but according to characteristics of effluent discharge, most probably PAHs are not presented in the discharge.  Therefore, the value of index 2.12б is qualified as equal 0 (Annex B, Table B22).

5.2.3.12. Oils and Fats

Usually there are two norms distinguished for the limiting discharges of oils and fats – one is for animal and vegetable oils, another is for mineral or synthetic oils and fats.  As a rule in the latter case the normatives of limiting discharges are one order higher as vegetable and animal oils and fats are more easily subject to biodegradation.  Nevertheless both normatives are aesthetic criteria of quality.  The concentration of animal and vegetable oils and fats in the matrix of quantitative assessment is reduced with the purpose of more precise reflection of actual concentrations met in certain industrial effluents.

There was no measuring of fats and oils content, but according to effluent discharge characteristics, a medium content of fats and oils is most likely present in effluent discharge of Minsk effluent treatment plant and low content of fats and oils at all the other enterprises. Therefore the value of index 2.13б for Minsk effluent treatment plant is qualified as 2 points and for all the other enterprises the score assigned is 1 (Annex B, Table B23).

5.2.3.13. Heavy Metals

There are eight metals which are of interest: iron, copper, zinc, nickel, chromium, cadmium, lead, and mercury.  The total concentration and content of metals are subject to determination. The negative impact of heavy metals upon the environment is reflected first of all by the quality of water and soil.  Firstly. dissolved metals increase the toxicity of water and deteriorate the quality of drinking water, they have an adverse effect on organoleptic characteristics of water, such as the taste. Assessment took place in relation to each of these heavy metals taken separately.

Iron (Fe)

The highest content of iron is observed in effluent discharge from wastewater treatment facilities of “Retchitsa vodokanal” and “Mozyrsky petroleum refinery” – 4.6 and 1.84 mg/l, that corresponds with a value of 5 points according to index 2.14a.

Medium concentrations of iron are typical for discharges from wastewater treatment facilities of the cities of Bereza, Soligorsk, Mogilev, Borisov, Zhlobin, Slutsk, they made up 0.97; 0.68; 0.63; 0.61; 0.61 and 0.6 mg/l respectively.  The value of this index for Bereza City is qualified as 3 points, and 2 points for all the other enterprises.

A low content of iron is observed in effluent discharges from wastewater treatment facilities of the cities of Bobruisk, Gomel, Minsk, Pinsk and Orsha - 0.57; 0.44; 0.36; 0.36 and 0.27 mg/l respectively, that correspond to a value of 1 point in the scoring sheets, the city of Orsha has 0.27 mg/l, which corresponds to a score of 0.

A lack of iron in the discharge is fixed in industrial effluents of Svetlogorsk “Khimvolokno” and Svetlogorsk heat station.  The value of index 2.14a in this case is qualified as equal to 0 (Annex B, Table B24).

Copper (Cu)

The highest concentration of copper is measured in effluent discharge of “Retchitsa vodokanal” wastewater treatment facilities – 0.13 mg/l.  In accordance with scoring sheets the value of index 2.15a is equal 4.

A medium value of copper content is typical for effluent discharge from wastewater treatment facilities of “Zhlobinsky vodokanal” – 0.095 mg/l, that corresponds with a value of 3 points.

Low values of copper content are observed in effluent discharge of wastewater treatment facilities of the cities of Minsk, Gomel, Mogilev, Borisov, Bobruisk, Svetlogorsk, Orsha, Pinsk, Bereza; they vary within the limits of 0.032 to 0.03 mg/l.  The value of index 2.15 for these enterprises is qualified as 0 (Annex B, Table B25).

Zinc (Zn)

The highest concentrations of zinc are observed in effluent discharge from wastewater treatment facilities of Svetlogorsk “Khimvolokno” and Gomel City – 0.29 and 0.24 mg/l.  In conformity with scoring sheets the value of index 2.16a is qualified as 5 points.

Medium values were observed in effluent discharges of the cities of Borisov and Minsk – 0.085 and 0.08 mg/l – therefore, the value of this index is qualified as 3 points.

Low values are typical for effluent discharge from wastewater treatment facilities of “Mozyrsky NPZ” – 0.043 mg/l – this corresponds with a value of 1 point.

The lowest content of zinc is registered in effluent discharge from wastewater treatment facilities of the cities of Zhlobin, Mogilev, Orsha, Retchitsa, Bobruisk, Bereza and Svetlogorsk heat station, they vary from 0.03 to 0.005 mg/l.

Zinc was not revealed in effluent discharge from wastewater treatment facilities of the cities of Pinsk, Soligorsk and Slutsk. For these enterprises the value of index 2.16a is qualified as 0 (Annex B, Table B26).

Nickel (Ni)

A medium content of nickel was observed only in effluent discharge from wastewater treatment facilities of “Retchitsa vodokanal” – 0.085 mg/l.  The value of index 2.17a is therefore qualified as 3 points.  The content of nickel in effluent discharge from wastewater treatment facilities of the cities of Minsk, Gomel, Mogilev, Orsha, Bobruisk, “Mozyrsky NPZ” and Svetlogorsk heat station were from 0.03 to 0.02 mg/l. Nickel was not measured in effluent discharges from wastewater treatment facilities of the cities of Borisov, Bereza, Pinsk, Zhlobin, Soligorsk and Slutsk. In accordance with limits established in scoring sheets the value of index 2.17a for Minsk City is qualified as 1 point, for all the other cities the value is qualified as 0 (Annex B, Table B27).

Chromium (Cr)

The Byelorussian part of the Dnipro basin is characterized by a low content of chromium in effluent discharges from wastewater treatment facilities of the cities of Minsk, Gomel, Mogilev, Borisov, Bobruisk, Zhlobin, Orsha, Svetlogorsk “Khimvolokno”, “Mozyrsky NPZ” – within the limits of 0.04 – 0.001 mg/l.  Chromium was not measured in effluent discharges from wastewater treatment facilities of “Retchitsa vodokanal”, Svetlogorsk heat station, nor in effluent discharges from wastewater treatment facilities of the cities of Pinsk, Soligorsk, Slutsk.  In accordance with limits established in the scoring sheet the value of index 2.18 for all enterprises is qualified as 0 (Annex B, Table B28).

Cadmium (Cd)

The concentration of cadmium is measured only in the effluent discharge of the Minsk effluent treatment plant and in effluents from the wastewater treatment facilities of the “Gomel vodokanal”.  It should be noted that these concentrations are insignificant – 0.0001 and 0.005 mg/l.  The cadmium content was not measured in effluent discharges of the other enterprises. The value of index 2.19 for all enterprises is equal 0 (Annex B, Table B29).

Mercury (Hg)

Mercury was not identified in effluent discharges of any of the 15 enterprises. Consequently the value of index 2.20 is qualified as 0 (Annex B, Table B30).

Lead (Pb)

Lead content is registered in effluent discharge from wastewater treatment facilities “Gomel vodokanal” and Svetlogorsk heat station in concentration of 0.0036 and 0.01 mg/l.  Lead content was not measured in effluent discharge from wastewater treatment facilities of Minsk effluent treatment plant, but according to characteristics of discharge, apparently it can contain a low content of lead.  Lead was not measured in the discharges of the other enterprises.  The value of index 2.21 is qualified as 0 (Annex B, Table B31).

Radioisotopes

The probability (proven or suspected) of the presence of radionuclids (Ce-137, Sr-90) with higher background levels in effluent discharge from wastewater treatment facilities of “Gomel vodokanal” and “Mozyrsky petroleum refinery” is possible, but unlikely and is impossible at other enterprises. Hence, the value of index 2.22 for the first two enterprises is qualified as 1 and is assigned 0 points for all the other enterprises (Annex B, Table B32).

5.2.4. Pollutant Load

Major data in relation to characteristics of pollutants discharge in the effluents from wastewater treatment facilities of enterprises in question for 2000 are given in Annex D.

5.2.4.1. Substances Consuming Oxygen or Exhausting Oxygen Content

The maximum quantity of organic matters according to BOD₅ is registered in effluent discharge from the Minsk effluent treatment plant, from wastewater treatment facilities of “Retchitsa vodokanal” and “Gomel vodokanal” – 3.36; 1.24 and 0.54 thousand tonnes respectively, that make up 42, 16 and 7% of the entire basin within the territory of Belarus.  In accordance with the scoring sheets, the value of index 3.1 is qualified as 5 points (Annex B, Table B33).

A large quantity of organic matter according to BOD₅ is discharged from wastewater treatment facilities of the cities of Bereza, Mogilev, Bobruisk, Borisov, Orsha, Svetlogorsk heat station, Soligorsk, “Mozyrsky petroleum refinery”, Slutsk, Pinsk, - 350, 290, 280, 260, 170,150, 130, 110, 100 and 100 tonnes respectively, that make up 4.4; 3.7; 3.5; 2.1; 1.9; 1.4; 1.3 and 1.3% of the whole basin.  The value of this index for these enterprises is qualified as 4 points (Annex B, Table B33).

The least quantity of organic matter according to BOD₅ is discharged from wastewater treatment facilities of Svetlogorsk “Khimvolokno” and “Zhlobinsky vodokanal” – 70 and 63 tonnes, that make up 0.9 and 0.6% accordingly.  These enterprises are assigned 3 points (Annex B, Table B33).

The highest content of organic matter in terms of COD is observed in effluent discharges from wastewater treatment facilities of “Retchitsky vodokanal” and “Berezovsky vodokanal”.  The value of index 3.2 was qualified as 3 points.  A medium content is observed in discharges from wastewater treatment facilities of the cities of Minsk, Gomel, Bobruisk, Soligorsk and from “Mozyrsky petroleum refinery” – 2 points are assigned.

A low content of organic matters in terms of COD is typical in effluent discharge from wastewater treatment facilities of the cities of Mogilev, Borisov, Orsha, Pinsk, Zhlobin, Slutsk, from Svetlogorsk “Khimvolokno” and Svetlogorsk heat station.  Hence, the value of this index is qualified as 1 point (Annex B, Table B34).

5.2.4.2. Total Suspended Solids (TSS)

The share of suspended solids in the total volume of effluent discharged to the basin of the Dnipro River in the territory of Belarus makes up 11.13 thousand tonnes.

The largest quantity of suspended solids is discharged from wastewater treatment facilities of the cities of Minsk, Retchitsa, Gomel, Mogivev – 5.14; 1.29; 0.76 and 0.75 thousand tonnes, that make up 46, 12, 9 and 7% of the entire discharge within the basin respectively.  In accordance with scoring sheets the value of index 3.3 is qualified as 5 points (Annex B, Table B35).

A large quantity of suspended solids is discharged from the wastewater treatment facilities of the cities of Bobruisk, Svetlogorsk heat station, “Mozyrsky petroleum refinery”, Borisov, Bereza, Orsha, Svetlogorsk “Khimvolokno”, Soligorsk, Pinsk - 370, 310, 310, 250, 250, 200, 160, 140 and 100 tonnes respectively.  This makes up from 8 to 1% of the entire discharge within the basin. The value of this index is qualified as 4 points.

A lesser quantity of suspended solids is discharged from wastewater treatment facilities of the cities of Zhlobin and Slutsk – 80 and 90 tonnes, that make up 0.72 and 0.80% of the entire quantity within the basin.  The value of index 3.3 is qualified as 3 points (Annex B, Table B35).

5.2.4.3. Total Dissolved Solids (TDS)

The total dissolved solids in effluent discharge within the basin in Belarus territory makes up 339.76 thousand tonnes.

The largest quantity is registered in the discharge from wastewater treatment facilities of the cities of Minsk, Mogilev, Svetlogorsk “Khimvolokno”, Bobruisk, Gomel, - 109.67; 36.99; 29.96; 26.95 and 21.04 thousand tonnes accordingly, that make up 32, 11, 9, 8 and 6% of the total volume.  The value of index 3.4 for these enterprises is qualified as 5 points (Annex B, Table B36).

A large quantity of dissolved solids is observed in effluent discharge from wastewater treatment facilities of Svetlogorsk heat station, as well as from wastewater treatment facilities of the cities of Orsha, Retchitsa, Soligorsk, “Mozyrsky petroleum refinery”, Borisov, Pinsk, Zhlobin – 13.28; 12.2; 10.81; 9.61; 9.4; 5.01 and 4.38 thousand tonnes, that makes up from 4 to 1.3% of the total volume discharged to the basin.  These enterprises are assigned 4 points.

The smallest quantity of dissolved solids is registered in the discharge from wastewater treatment facilities of the town of Bereza – 1.89 thousand tonnes, that make up 6%.  The value of index 3.4 is qualified as 3 points (Annex B, Table B36).

5.2.4.4. Phosphorus

There are 2.02 thousand tones of phosphorus in effluent discharged to the Dnipro River basin in the territory of Belarus.  The largest quantity is observed in effluent discharge from wastewater treatment facilities of the cities of Minsk, Gomel, Borisov, Retchitsa, Bobruisk - 800, 180, 170, 160 and 160 tonnes respectively that make up 40, 9, 8, 8, and 8% of the total volume.  In accordance with scoring sheets the value of index 3.5 is qualified as 5 points (Annex B, Table B37).

A large quantity is also registered for the cities of Pinsk, Mogilev, Orsha, Bereza, Zhlobin, Soligorsk and Mozyr (i.e., 70, 60, 40, 30, 30, 30 and 50 tonnes respectively), that make up 3.5; 3; 2; 1.5; 1.5; 1.5 and 2.5% of the total volume in the basin.  These enterprises are assigned 4 points.  The discharge of phosphorus from the wastewater treatment facilities of Svetlogorsk “Khimvolokno”, Svetlogorsk heat station, and the town of Slutsk make up 20 tonnes from each enterprise, which is below 1%.  The value of index is 0 (Annex B, Table B37).

5.2.4.5. Ammonia Nitrogen

Total ammonia nitrogen in effluent discharge in the Dnipro River basin within the territory of Belarus makes up 5.36 thousand tonnes.  The largest quantity of ammonia nitrogen is measured in effluent discharge from wastewater treatment facilities of the cities of Minsk, Retchitsa, Mogilev and Borisov – 2.1; 0.81; 0.39 and 0.39 thousand tonnes.  In percentage terms it makes up 39; 15.7 and 7% of the total content within the basin.  Hence, the value of index 3.6 is qualified as 5 points (Annex B, Table B38).

A large quantity of ammonia nitrogen is observed in effluent discharge from wastewater treatment facilities of the cities of Bereza, Bobruisk, Gomel, Pinsk, Soligorsk, Slutsk - 250, 240, 200, 180, 150 and 70 tonnes respectively, that make up 4.7; 4.5; 4; 3.5; 2.8 and 1.3% of the total quantity within the basin.  These enterprises are assigned 4 points.

A medium content of ammonia nitrogen is observed in effluent discharge from wastewater treatment facilities of the city of Orsha, Svetlogorsk heat station, Svetlogorsk “Khimvolokno”, “Mozyrsky petroleum refinery” and Zhlobin - 40, 40, 30, 20 and 20 tonnes accordingly.  In relation to the total content within the entire basin it makes up 0.75; 0.75% 0.6; 0.4 and 0.4 % (3 points) (Annex B, Table B38).

5.2.4.6. Nitrate Nitrogen

Effluent discharged to the Dnipro River basin contains 1.91 thousand tonnes of nitrate nitrogen.  The major quantity of nitrate nitrogen is measured in effluent discharge of the Minsk effluent treatment plant – 1.41 thousand tonnes, that make up 74% of the total content within the basin.  The value of index 3.7 is qualified as 5 points (Annex B, Table B40).

A large quantity of nitrate nitrogen is present in effluent discharge from wastewater treatment facilities of the cities of Borisov, Gomel, Orsha, Mozyrsky petroleum refinery, Soligorsk, Retchitsa, and the Svetlogorsk heat station - 90, 70, 60, 50, 40, 20, 20 and 20 tonnes accordingly, that make up 4.7; 3.7; 3.1; 2.6; 2.1; 1.1 and 1% of the total content within the basin. The value of this index is qualified as 4 points.

A medium concentration of nitrate nitrogen is observed in effluent discharge from wastewater treatment facilities of Svetlogorsk “Khimvolokno”, cities of Pinsk and Slutsk on average in tonnes per year, that makes up 0.5% of total content all over the basin.  The value of index is qualifies as 3 points.

A low content is registered in the discharge from wastewater treatment facilities of the town of Bobruisk – 2 tonnes.  Nitrate nitrogen was not measured in effluent discharges of the cities of Mogilev, Bobruisk, Bereza and Zhlobin.  Hence, the value of index 3.7 for these enterprises is qualified as 0 (Annex B, Table B39).

5.2.4.7. Nitrite Nitrogen

Total nitrite nitrogen in effluent discharge in the Dnipro River basin within the territory of Belarus makes up 140 tonnes.  The largest quantity of ammonia nitrogen is revealed in effluent discharge from wastewater treatment facilities of the Minsk effluent treatment plant – 100 tonnes, that makes up 71% of the total content throughout the basin.  A large quantity of nitrate nitrogen is observed in effluent discharge from wastewater treatment facilities of the city of Borisov – 10 tonnes per year, that make up 7.5% of the total volume of discharge. The value of index 3.8 for these cities is qualified as 5 points (Annex B, Table B40).  Nitrite nitrogen was not measured in effluent discharges from wastewater treatment facilities of the other cities.  These cities are assigned a score of 0 (Annex B, Table B40).

5.2.4.8. Oil Products

The total amount of oil products in effluent discharge in the Dnipro River basin is 180 tonnes per year.  The largest content of oil products is revealed in effluent discharges from wastewater treatment facilities of the cities of Minsk, Mogilev, Gomel, Borisov, Bobruisk, from Svetlogorsk “Khimvolokno” and Orsha – 80, 20 and all the others 10 tonnes each respectively, that make up 44.11 and 6% of the total content.  The value of index 3.9 for these enterprises is qualified as 5 points ((Annex B, Table B41).  Oil products were not revealed in effluent discharges from wastewater treatment facilities of the cities of Retchitsa, Bereza, Pinsk, Zhlobin, Soligorsk, Slutsk, as well as from wastewater treatment facilities of Svetlogorsk heat station and “Mozyrsky petroleum refinery”.  The value of this index was qualified as 0 (Annex B, Table B41).

5.2.4.9. Persistent Organic Pollutants

The content of persistent organic pollutants in the discharges of all enterprises in question was not measured and most probably is not presented in effluents.  Hence, the value of index 3.10 is qualified as 0 (Annex B, Table B42).

5.2.4.10. Phenols

Total phenols in effluent discharge over the Dnipro River basin make up 1130 tonnes. The largest content of phenol is revealed in effluent discharge from wastewater treatment facilities of the cities of Mogilev, Retchitsa and Gomel - 420, 390 and 10 tonnes respectively, that make up 37, 35 and 9%.  The value of index 3.11 for these enterprises is qualified as 5 points (Annex B, Table B43).  The availability of phenols was not measured in effluent discharges from the other wastewater treatment facilities, therefore these enterprises are assigned 0.

5.2.4.11. Polyaromatic Hydrocarbons

The content of polyaromatic hydrocarbons in effluent discharge from wastewater treatment facilities of 15 enterprises in question over the Dnipro River basin within the territory of Belarus was not measured.  Most probably they are absent in the effluents. Accordingly the value of index 3.12 is qualified as 0 (Annex B, Table B44).

5.2.4.12. Fats and Oils

The concentration of fats and oils (animal or vegetable origin) was not measured, most probably there is a low content of oils and fats in the discharges from wastewater treatment facilities of the 15 enterprises in the basin of the Dnipro River.  The value of index 3.13 is qualified as 1 point (Annex B, Table B45).

5.2.5. Heavy Metals

Iron

Total iron in effluent discharges in the Dnipro River basin within the territory of Belarus makes up 336.33 thousand tonnes.  The highest content of iron is observed in effluent discharges from wastewater treatment facilities of the cities of Minsk, Retchitsa, Mogilev, “Mozyrsky petroleum refinery”, Bobruisk and Gomel – 89, 43, 40, 36, 25 and 25 thousand tonnes, that make up 26, 13, 12, 11, 7, 5 and 7% respectively.  The value of index 3.14 is qualified as 5 points (Annex B, Table B46).

A high content of iron is observed in effluent discharges from wastewater treatment facilities of the cities of Borisov, Soligorsk, Slutsk, Orsha, Pinsk, Bereza – 13; 9; 6; 4.8; 4.7 and 3.7 thousand tonnes, that make up 4;. 2.7; 1.7; 1.4; 1.4 and 1% of total content throughout the basin.  The value of this index for these enterprises is qualified as 4 points.  The availability of iron in effluent discharges from wastewater treatment facilities of Svetlogorsk “Khimvolokno” and Svetlogorsk heat station is not measured, therefore the value is assigned as 0.

Copper

The total copper in effluent discharges in the Dnipro River basin within the territory of Belarus makes up 14.78 thousand tonnes.  The highest content of copper is observed in effluent discharges from wastewater treatment facilities of the cities of Minsk, Mogilev, Retchitsa and Gomel – 7.85; 1.57; 1.24 and 0.85 thousand tonnes, that makes up 5.3; 1.6; 1.2 and 0.9% accordingly. In conformity with scoring sheets the value of index 3.15 was qualified as 5 points (Annex B, Table B47).

High content of copper is observed in effluent discharges from wastewater treatment facilities of the cities of Zhlobin, Borisov, from Svetlogorsk heat station, Orsha, Bobruisk, Svetlogorsk “Khimvolokno” – 730, 390, 320, 280, 270 and 210 tonnes, that makes up 4.9; 2.6; 2.2; 1.9; 1.8 and 1.4% of total content over the basin.  This corresponds with the value of 4 points. Medium content of copper is observed in effluent discharges from wastewater treatment facilities of “Mozyrsky petroleum refinery” and Pinsk City – 140 and 120 tonnes, that constitutes 0.9 and 0.8% of total content.  These enterprises were put down 3 points. Low content is observed in effluent discharges of the town of Bereza – 10 tonnes, that makes up 0.07% - 2 points.

Presence of copper was not revealed in effluent discharge from wastewater treatment facilities of the cities of Soligorsk and Slutsk.  The value of index 3.15 is qualified as 0 (Annex B, Table B47).

Zinc

Total zinc in effluent discharge makes up 39.92 thousand tonnes.  The highest content of zinc is observed in effluent discharges from wastewater treatment facilities of the cities of Gomel, Minsk, Svetlogorsk “Khimvolokno” – 13.63; 12.02 and 7.78 thousand tonnes accordingly, that made up 34, 30 and 20%.  The value of index 3.16 is qualified as 5 points. High content of zinc is observed in effluent discharges from wastewater treatment facilities of the cities of Borisov, Mogilev and “Mozyrsky petroleum refinery” – 1.82; 1.27 and 0.83 thousand tonnes, that makes up 4.6; 3 and 2% of total content over the Dnipro River basin.  The value of index is qualified as 4 points. Medium content of zinc is typical for effluent discharges from wastewater treatment facilities of the cities of Orsha, Zhlobin, Bobruisk and Svetlogorsk heat station – 0.64 0.55; 0.45 and 0.2% accordingly of total content over the basin.  These enterprises were put down 3 points. Low content is observed in effluent discharges from wastewater treatment facilities of the town of Bereza – 10 tonnes, that makes up 0.025% of total content over the Dnipro River basin and qualified as 2 points. Presence of zinc was not revealed in effluent discharges from wastewater treatment facilities of the cities of Retchitsa, Pinsk, Soligorsk and Slutsk. In these cases the value of index 3.16 is qualified as 0 (Annex B, Table B47).

Nickel

Total nickel in effluent discharges in the Dnipro River basin within the territory of Belarus makes up 7.25 thousand tonnes.  The highest content of nickel in effluent discharges is observed at wastewater treatment facilities of the cities of Minsk, Gomel, Mogilev – 4.9; 0.7 and 0.42 thousand tonnes accordingly, that makes up 68; 9.7 and 6% of total content over the basin.  The value of index 3.17 is qualified as 5 points. High content of nickel is observed in effluent discharges from wastewater treatment facilities of the city of Orsha, “Mozyrsky petroleum refinery”, Svetlogorsk heat station and Bobruisk – 240, 190, 110 and 90 tonnes accordingly, that makes up 3.3; 2.6; 1.5 and 1.2% of total nickel content.  The value of index is qualified as 4 points. Medium content of nickel is typical for wastewater treatment facilities of Svetlogorsk “Khimvolokno” – 50 tonnes or 0.7% of total content in effluent discharged in the Dnipro River basin within the territory of Belarus.  This corresponds to the value of 3 points. Presence of nickel was not revealed in effluent discharges from wastewater treatment facilities of the cities of Retchitsa, Borisov, Bereza, Pinsk, Zhlobin, Soligorsk and Slutsk.  The value of index for these cities is qualified as 0 (Annex B, Table B49).

Chromium

Thirteen (13) thousand tonnes of chromium per year is discharged in wastewater in Belarus part of the Dnipro River basin.  The highest content of chromium is observed in effluent discharges from wastewater treatment facilities of the cities of Minsk and Bobruisk – 9.81 and 0.8 thousand tonnes, that makes up 74 and 6% of total content over the basin.  The value of index 3.18 is qualified as 5 points (Annex B, Table B51).High content of chromium is presented in effluent discharges from wastewater treatment facilities of the cities of Mogilev, Borisov, Gomel and Zhlobin – 660, 620, 500 and 220 tonnes accordingly, that constitutes 4.99; 4.69; 3.8 and 1.7% of total content over the basin (4 points). Medium content of chromium is registered in effluent discharge from wastewater treatment facilities of Svetlogorsk “Khimvolokno”, “Mozyrsky petroleum refinery” and the cities of Bereza and Orsha – 80, 40, 20 and 20 tonnes, that makes up 0.6; 0.3; 0.15 and 0.15% of total content over the Dnipro River basin.  The value of index is qualified as 3 points. Presence of chromium was not identified in effluent discharges from wastewater treatment facilities of the cities of Retchitsa, Pinsk, Soligorsk, Slutsk and Svetlogorsk heat station.  The value is qualified as 0 (Annex B, Table B50).

Cadmium

Among 15 enterprises in question cadmium is revealed only in effluent discharge from wastewater treatment facilities of the cities of Minsk and Gomel – 0.1 and 0.5 tonnes. Presence of cadmium was not identified in effluent discharges of other enterprises.  The value of index 3.19 is qualified as 0 (Annex B, Table B51).

Mercury

Presence of mercury was not revealed in effluent discharges from wastewater treatment facilities of 15 enterprises in question.  The value of index 3.20 is qualified as 0 (Annex B, Table B52).

Lead

Total lead in effluent discharges in the Dnipro River basin within the territory of Belarus makes up 280 tonnes per year. High content of lead is revealed only in effluent discharge from wastewater treatment facilities of the city of Gomel and Svetlogorsk “Khimvolokno” – 200 and 50 tonnes, that makes up 71 and 19% of total content over the basin.  The value of index 3.21 is qualified as 5 (Annex B, Table B53).  Presence of lead is not revealed at the other enterprises, hence, the value of index is qualified as 0.

Radionuclids (Ce-139  и Sr-90)

Effluent discharges from wastewater treatment facilities of the 15 enterprises in question in the Dnipro River basin within the territory of Belarus do not contain components of isotopes (Ce-139  и Sr-90).  The value of index 3.22 is qualified as 0 for all enterprises (Annex B, Table B 54).