Chemical pollution

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4.4.1.  Chemical pollution

Chemical pollution refers to the adverse effects of chemical contaminants released to standing or marine water bodies as a result of human activities. Chemical contaminants are here defined as compounds that are toxic and/or persistent and/or bioaccumulating. For the Dnipro Basin, chemical pollution also refers to the exceeded guideline levels of chemical substances in water bodies of the three riparian countries, and chemical pollution load carried with the river flow to the Black Sea. The transboundary status of the issue is reflected in Table 4.1. A detailed causal chain showing the links between the immediate and underlying causes of this issue is shown in Figure 4.10.

 

Environmental impacts

The impacts of this issue are linked closely with those of a number of other issues including changes in the groundwater regime (Section 4.3.2), flooding events and elevated groundwater levels (Section 4.3.3) and modification and loss of ecosystems and ecotones (Section 4.5). The impacts of other water resource pollution issues in this section such as microbiological pollution, eutrophication, suspended solids, solid wastes and accidental spills and releases (Section 4.4) are also closely linked.

 

Changes in biodiversity of aquatic, riparian and terrestrial biological resources

The most visible indication of environmental pollution associated with urban and industrial sources is the existing state of river ecosystems. Such ecosystems are greatly affected by municipal and industrial wastewater discharges, particularly those that receive highly variable treatment levels. The continuous pollution load in certain sections of the Dnipro Basin often causes degradation of the rheophilous community structure and species composition.

 

Biological survey results from a section of the Sozh River near Gomel, Belarus, have shown that there is a direct relationship between a progressively increasing anthropogenic load and a reduction in the diversity of zooplankton species. In upstream sections there were 133 species compared to 38-46 species in the section within the city boundaries, and 72-74 species downstream of the discharge. The total number of species inhabiting the examined river sections was 180.

 

A similar picture emerges near large industrial centres in the Berezina River, where taxonomic diversity is reduced as pollution load increases. In the river section near Borisov the number of bottom community species fell from 90 to 57, and in the river section near Bobruisk from 50 to 39. Individual macroinvertebrate species and whole taxonomic groups were found to be missing in the downstream sections, particularly those sensitive to changes in water quality. For example, the number of mayfly species reduced from 8 to 2 near Borisov, and no mayfly species were found downstream of Bobruisk. The Oligosaprobic Blackfly (Simuliidae), which is highly sensitive to changes in water quality, occurred only in the upstream sections. Further details on changes in biodiversity are given in Section 3.3.2 reviewing of the 2000-2001 field survey resu1ts (water quality, metal contamination, persistent organic contamination, assessment of ecological status and transboundary transport of pollution).

Immediate causes

The immediate causes of chemical pollution in the Dnipro Basin can be grouped into two hierarchical levels. The first distinguishes point sources and diffuse sources of pollution. The second more detailed level can be broken down into the following (also refer to Table 4.17):

- Operational discharge of liquids and gaseous effluents including cooling waters (point source);

- Emissions from storage of chemical products (point and diffuse source);

- Emissions from storage of solid waste (point and diffuse source);

- Emissions from storage of liquid wastes (point and diffuse source);

- Emissions from transport (point and diffuse source);

- Runoff (point and diffuse source);

- Growth in the production of waste (point and diffuse source).

 

1. Operational discharge of liquids and gaseous effluents including cooling waters

 

In general, major water supply/sewerage systems are in poor repair and have reached a high level of depreciation. The poor state of municipal utilities in the Dnipro Basin is illustrated by the fact that wastewater discharges from municipal wastewater treatment plants have been recognised as a major (immediate) source of chemical and microbiological pollution and eutrophication. Descriptions of the most significant pollution sources (or ‘hotspots’) in the Dnipro Basin are shown in Section 3.3.3. The transboundary transport of pollution through the Basin is described in Section 3.3.2.

 

The total annual volume of point source wastewater discharges in the Dnipro Basin in 2000 was 6,843,000,000 m³ (a breakdown by country is shown in Figure 4.6) Of the total volume, the majority receives no, or only partial treatment (Figure 4.7). In 2000, the water bodies of the Pripyat Basin received 164,000,000 m³ of wastewater within Belarus, and 363,730,000 m³ within Ukraine. Of that, 121,560,000 m³ received no treatment; 102,960,000 m³ was classified as ‘normatively clean’, i.e. not requiring treatment; and 133,210,000 m³ was treated to the required standard.

 

Figure 4.6 Annual volume of point source wastewater discharges in the Dnipro Basin in 2000 (m³/year)

 

 

Figure 4.7 Level of treatment of wastewater discharges by total and each country (year)

 

The pollution load dynamics in the Russian part of the Dnipro Basin are shown in Table 4.5. Table 4.6 shows the annual amounts of pollutants discharged with effluents from point sources in the Russian part of the Dnipro Basin. Data on the pollution load contained in effluents discharged into the Upper Dnipro in 1995 and 2000 are presented in Table 4.7.

 

Table 4.5. Pollution load dynamics in the Russian part of the Dnipro Basin

 

 

Table 4.6. Pollutants discharged with effluents from point sources in the Russian part
of the Dnipro Basin

 

 

Table 4.7        Pollution load contained in effluents discharged into the Upper Dnipro in 1995 and 2000

 

 

The most polluted river sections in Belarus associated with wastewater discharges are the Svisloch River downstream of Minsk, the Berezina River downstream of Bobruisk, the Dnipro River downstream of Mogilev and Rechitsa, the Pripyat River downstream of Mosyr, the Yaselda River downstream of Beresa, and the Usa River downstream of Gomel. The actual dilution capacities of these rivers are far too low to be able to meet the dilution demand.

 

In 2000, the Dnipro tributaries within Belarus received 7,930 tonnes of organic matter (in terms of BOD); 5,400 tonnes of ammonium nitrogen; 1,909 tonnes of nitrate nitrogen; 180 tonnes of oil products; 336 tonnes of iron; and 14.8 tonnes of copper. The contribution of transboundary, diffuse and point sources of pollution to the total pollution flow from the territory of Belarus can be evaluated from transboundary pollution load estimates and data on pollution loads entering the rivers with wastewater discharges (averaged over the period of 1995-2000). The results of this evaluation are presented in Table 4.8 Further information on the transboundary transport of pollution in the Basin is presented in Section 3.3.3.

 

Table 4.8  Comparative contribution of point and diffuse pollution sources to the total pollution flow from Belarus (indicative data)

 

In Belarus, 80% of the total wastewater volume entering the Dnipro River and its tributaries contains polluting substances at elevated concentrations even after primary, secondary and tertiary treatment. This proportion varies from 7% to 48% at the city/town level and from 8% to 25% at the Oblast level. Wastewater discharges are concentrated in the Berezina and Svisloch River catchments, with the latter receiving the major part of the pollution load (Table 4.9). The City of Minsk appears to be the major contributor in terms of volume and pollution load, generating more than 25% of the total (Figure 4.8). This has greatly affected the ecological state of the Svisloch River itself, and the Dnipro Basin as a whole.

Table 4.9  Pollution load in the Svisloch River catchment

 

 

Figure 4.8 % contribution of pollution from the city of Minsk to the Svisloch River and the Dnipro Basin (2000)

 

Within Ukraine, about 900,000 tonnes of pollutants are discharged with effluents into the Dnipro Basin water bodies from point sources. In 1990, the total amount of discharged pollutants was 793,000 tonnes, whereas the 1991-1995 average annual pollutant discharge was 1,003,000 tonnes. Clearly, the decline in production and associated water consumption during this period did not result in a reduction of pollution load discharged into the Dnipro Basin rivers.

 

2. Emissions from storage of chemical products, solid wastes and liquid wastes

 

Approximately 5,000 agrochemical and expired pesticide storage sites are scattered throughout rural areas in Ukraine. Within the Russian Federation, about 50% of chemical fertilisers and agrochemicals are stored at unorganised and often uncontrolled sites.

 

According to data from a waste inventory survey carried out in the mid 1990s, Ukraine has 2,670 waste landfill and disposal sites, with about a half of them (1,310 sites) located within the Dnipro Basin. These figures do not account for the numerous on-site industrial waste storage facilities, and smaller waste dumps located in rural areas.

There are 300 toxic waste disposal sites in Ukraine (161 of them being located in the Dnipro Basin), containing toxic substances at concentrations exceeding the respective MAC limits by a factor 50. None of these sites are well engineered, thereby posing a continuous threat to groundwater and surface waters.

 

Despite the decline in production, toxic waste generation remains high in the Russian Federation and in 2000 reached 125% of the 1990 level (1,200,000 tonnes). This equates to 1.1% of the total annual amount of waste generated in the Russian Federation. In the region, usage of toxic materials in industrial processes has grown 2.4 fold over the last five years (from 66,000 tonnes in 1995 to 215,000 tonnes in 2000). Further details on waste disposal sites can be found in Section 4.4.2 (immediate causes of microbiological pollution).

 

3. Runoff from agricultural land and urbanised areas

 

Of the total amount of nitrogen and phosphorus applied to agricultural land, about 20% of nitrogen and 5% of phosphorus reach the water bodies with surface runoff. In Belarus, agricultural soils contain phosphorus and nitrogen compounds at elevated concentrations. In 1989-1990, the annual nutrient load discharged into the surface waters of the Dnipro Basin from agricultural areas was 21,200 tonnes of nitrogen and 610 tonnes of phosphorus. Figure 4.9 reflects the percentages contributed by various sources to the total nutrient load.

 

Another related problem is the large-scale application of pesticides in the riparian countries. Within the Russian Federation, the annual pesticide runoff rate is about 1 kg/ha. Further details on the level of pesticides in the Dnipro environment can be found in Section 3.3.2 (2000-2001 field survey results).

 

In Belarus, significant pollution load enters surface waters with urban runoff with 4,530 tonnes/year of oil products, 10,260 tonnes/years of organic matter in terms of BOD₅, 780 tonnes/year of ammonium nitrogen and 330 tonnes/year of phosphates (1990 data).

 

Figure 4.9 % Contribution of 3 sources to the total nutrient load

 

According to survey data provided by the Ukrainian Municipal Utility Research & Design Institute “UkrKommunNIIProgress”, about 78% of suspended matter, 20% of organic matter and 68% of oil products enter surface waters with rainstorm runoff drained from urban areas. Oil products contained in soils are washed out into the surface waters and accumulated in the bottom sediments. Monitoring data over the past 10 years indicates that oil product concentrations in water have increased over that period, reaching 0.14 mg/l in 2000, compared to the MAC limit for fishery water use of 0.05 mg/l.

 

4. Growth in the production of waste

 

For details on the growth of waste production, refer to the immediate causes of chemical pollution described above and Sections 3.1.4 and 4.4.6 on mineral resources and solid waste pollution in the Basin.

 

Underlying sectoral causes

 

The underlying causes of this issue arise in the following key sectors: industry, agriculture, and urbanisation. Energy, aquaculture and transport contribute to a lesser degree. A list of the priority sectors for all issues is presented in Table 4.18 (Section 4.7)

 

A detailed causal chain reflecting the links between the immediate and underlying sectoral causes of this issue is shown in Figure 4.10 and a detailed description of terminology used in this causal chain is given in the definition of terms in Annex 2.

Priority inter-sectoral issues

Based on the causal chain in Figure 4.10, the priority sectoral resource uses and practices and the underlying political, economic and governance causes of this transboundary issue can be identified. These are shown in the Strategic Action Programme (SAP) decision making management tool (Figure 4.11).

 

 

Figure 4.11 SAP decision making management tool for the issue of chemical pollution

 

The SAP decision making management tool shows the priority sectors for this issue (colour coded with the causal chain) together with three hierarchical levels of concern (shown in Section 4.3.1). Within each level the priority resource uses and practices and the underlying political, economic and governance causes for each transboundary issue are listed. These can either cut across all sectors (e.g. Lack of adequate finance) or be sector specific (e.g. inadequate implementation of clean technologies).

 

Justification for sectoral prioritisation

 

Environmental degradation in the Dnipro Basin can largely be attributed to the long-term chemical contamination of air, soil, surface waters and groundwater. The impact on the natural environment of anthropogenic chemical pollution is a legacy of the large-scale unsustainable development of industry, agriculture and urban areas in the Basin.

 

In terms of point and diffuse sources of chemical pollution, diffuse sources are more significant for the Basin as a whole, as they relate to spatial pollution, i.e.:

 

- Emissions from storage or disposal of liquid/solid waste and chemicals;

- Atmospheric deposition of pollution;

- Application of fertilisers;

- Application of agrochemicals;

- Pollution of urbanised areas and transport networks.

 

Moreover, diffuse pollution sources, as opposed to point sources, are very difficult to regulate, and their adverse impact is likely to grow in the short to medium term, as economic activity increases. The most effective options to prevent and reduce diffuse pollution are:

 

- The establishment/reconstruction of water protection zones and strips;

- The development and implementation of environmentally sound waste management systems and facilities for all types of waste; and

- the collection and treatment of rainstorm runoff from urban areas.