Text consolidated by Valsts valodas centrs (State Language Centre) with amending regulations of: 16 January 2007 [shall come into force from 19 January 2007]; 15 April 2008 [shall come into force from 19 April 2008]; 27 July 2010 [shall come into force from 14 August 2010]; 19 February 2013 [shall come into force from 22 February 2013]; 4 April 2023 [shall come into force from 7 April 2023]. If a whole or part of a paragraph has been amended, the date of the amending regulation appears in square brackets at the end of the paragraph. If a whole paragraph or sub-paragraph has been deleted, the date of the deletion appears in square brackets beside the deleted paragraph or sub-paragraph.

Republic of Latvia Cabinet Regulation No. 34 Adopted 22 January 2002

Regulations Regarding Discharge of Polluting Substances into Water

Issued pursuant to Section 11, Paragraph two, Clause 2, Section 18,
Paragraph two, Clause 1, Section 45, Paragraph one
and Section 46, Paragraph two of the Law On Pollution

I. General Provisions

1. The Regulation prescribes:

1.1. the threshold values for wastewater discharge and prohibitions for discharge of polluting substances into water;

1.2. those highly sensitive territories to which increased requirements for the urban wastewater treatment apply, the criteria for determination, procedures for management and the boundaries of such territories;

1.3. the procedures by which an operator shall control the quantity of discharge of polluting substances, perform monitoring and provide the relevant information;

1.4. the procedures by which the State limited liability company "Latvian Environment, Geology and Meteorology Centre" (hereinafter - Centre) shall ensure public accessibility to the information.

[16 January 2007; 27 July 2010]

2. This Regulation shall apply to all waters:

2.1. surface waters:

2.1.1. [19 February 2013];

2.1.2. [19 February 2013];

2.1.3. [19 February 2013];

2.1.4. [19 February 2013];

2.2. ground waters;

2.3. wastewaters (waters which due to the activities of humans have changed their initial physical, chemical or biological properties) including:

2.3.1. domestic wastewater (wastewater originating from public and residential buildings and places for provision of services due to various physiological, hygiene, and household activities);

2.3.2. run-off rain water (waters which form from atmospheric deposition by flowing down from the roofs of buildings, streets and other territories with a full or partial surface cover);

2.3.3. industrial wastewater (wastewaters originating from entrepreneurship or in industrial sites and may not be classified as domestic wastewater nor run-off rain water);

2.3.4. urban wastewater (domestic wastewater, a mixture of domestic wastewater with industrial wastewater and run-off rain water).

[19 February 2013; 4 April 2023]

3. Measures connected with implementation of requirements of this Regulation may not directly or indirectly increase water, air or soil pollution.

4. In performing discharge into water, the environmental quality objectives laid down in the Water Management Law (hereinafter - environmental quality objectives) and water quality standards shall be taken into account. If it is required to receive a Category A or Category B permit (hereinafter - the permit) for discharge of pollution into water in accordance with the law On Pollution, the State Environmental Service (hereinafter - the Service) shall harmonise the conditions of the permit with the relevant environmental quality objectives and water quality standards, and also take them into account when registering Category C polluting activities.

[4 April 2023]

5. If wastewater contains the substances referred to in Chapter II of this Regulation, the conditions referred to in Chapters III and IV of this Regulation shall be applied for the discharge thereof into the water.

[16 January 2007; 27 July 2010]

6. In order to restrict the discharge present in the surface waters, the operator shall use the best available technical methods or environmental abatement technologies.

II. Priority Substances, also Particularly Dangerous Substances and Dangerous Substances to the Aquatic Environment

[27 July 2010]

7. Priority substances, also particularly dangerous substances to the aquatic environment, are chemical substances, which present a significant risk to the aquatic environment (hereinafter - priority substances). Particularly dangerous are substances which are toxic, stable in the aquatic environment and may accumulate in the biota.

[27 July 2010]

8. There are the following groups of priority substances:

8.1. organohalogen compounds and substances which may form such compounds in the aquatic environment;

8.2. organophosphorus compounds;

8.3. organotin compounds;

8.4. substances which possess carcinogenic properties in or via the aquatic environment also substances referred to in Paragraph 12 of this Regulation, if they possess carcinogenic properties;

8.5. mercury and its compounds;

8.6. cadmium and its compounds;

8.7. persistent mineral oils and hydrocarbons of petroleum origin;

8.8. persistent synthetic substances which may float, remain in suspension or sink and which interfere with the use of water.

[27 July 2010]

9. A substance belonging to a group of priority substances shall not be considered as particularly dangerous to the aquatic environment, if it is not biologically harmful or rapidly converts into a biologically harmless substance.

[27 July 2010]

10. Priority substances are specified in Annex 1 to this Regulation.

[27 July 2010]

11. Chemical substances dangerous to the aquatic environment are those where the deleterious effect of their discharge depends on the characteristics of the accepting waters and may be restricted within a certain area (hereinafter - dangerous substances).

12. There are following groups of dangerous substances:

12.1. metals, metalloids and their compounds including zinc, copper, nickel, chromium, lead, selenium, arsenic, antimony, molybdenum, titanium, tin, barium, beryllium, boron, uranium, vanadium, cobalt, thallium, tellurium and silver;

12.2. biocides and substances or products obtained in reactions;

12.3. substances which have a deleterious effect on the taste or smell of products intended for consumption derived from the aquatic environment, as well as chemical substances and chemical products liable to give rise to such substances in water;

12.4. toxic or persistent (stable) organic compounds of silicon, and substances which may give rise to such compounds in water, excluding those which are biologically harmless or are rapidly converted in water into biologically harmless substances;

12.5. phosphorus and inorganic compounds of phosphorus;

12.6. non-persistent (non stable) mineral oils and hydrocarbons of petroleum origin;

12.7. cyanides and fluorides;

12.8. substances which have an adverse effect on the oxygen content in water, particularly ammonia and nitrites.

13. Dangerous substances are specified in Annex 2 of this Regulation.

14. The Centre shall compile and register the information regarding priority substances and dangerous substances which are discharged into the aquatic environment, as well as regarding the importers, users and producers of the referred to substances in Latvia and the imported, used and produced amounts of the relevant substances.

[27 July 2010]

15. The Centre shall assess the information included in Annex 2 to this Regulation at least once every six years, updating river basin district management plans in accordance with the Water Management Law on the basis of the following:

15.1. data regarding the dangerousness of the substance or group of substances to the aquatic environment and human health;

15.2. the aquatic environment quality standards specified in laws and regulations;

15.3. the results of the risk assessment of the substance;

15.4. the amount of the imported, produced and used substance, as well as the conditions for use or storage;

15.5. substantiated proposals and expert opinions submitted by natural persons and legal persons.

[4 April 2023]

16. The public, the environmental protection and public health State authorities shall be informed of the updating of the list of substances referred to in Annex 2 to this Regulation during the public discussion of river basin district management plans.

[4 April 2023]

III. Discharge of Priority Substances and Dangerous Substances into Surface Waters

[27 July 2010]

17. The requirements laid down in this Chapter shall apply to the discharge of priority substances or dangerous substances into the surface waters, except for discharge which has been caused after disposal of excavated material, deepening of the bed of the water body or discharge caused by the operation of ships in the territorial sea of the Republic of Latvia.

[19 February 2013]

18. An operator may perform discharge of priority substances or dangerous substances into the surface waters, not exceeding the discharge limits specified in the permits for Category A or B polluting activities (hereinafter - permit).

[16 January 2007; 27 July 2010]

19. In the application for obtaining a permit, including in case of planning significant changes in activities, the operator shall, regardless of the type of discharge of wastewater (into the environment, a centralised collecting system, or to external treatment plants), provide the following information:

19.1. all priority substances or dangerous substances already used in the relevant equipment or produced or formed in the production process, and also priority substances or dangerous substances contained in wastewater received from other operators according to the information provided by the operators;

19.2. substances which an operator has foreseen to use and which may form during the process of the polluting activity, if the polluting activity has not been commenced yet or significant changes in the present polluting activity are planned;

19.3. results of the monitoring performed by the operator regarding the substances referred to in Sub-paragraph 19.1 of this Regulation which were detected in the wastewater after treatment thereof. If wastewater does not contain (or it is foreseen that it will not contain) priority substances or dangerous substances and they are not or will not be discharged in receiving waters, it shall be substantiated documentarily with the results of testing or the calculation method according to the raw material mass balances or inventory data;

19.4. the results of the initial calculation of the mixing zone in receiving waters (surface water body) downstream of the point discharge point of priority substances or dangerous substances if the concentration of one or more of the abovementioned substances in the discharged wastewater exceeds the environmental quality standards laid down in the laws and regulations regarding water protection. The calculation made shall be accompanied by the used data and calculation results, supported by the results of testing, including the results of testing for background concentrations of the respective priority or dangerous substances in the surface water body, and an official statement from the merchant regarding hydrological parameter measurements characterising the surface water body which are necessary for the initial calculation of the mixing zone. The required analyses shall be performed by a laboratory accredited in the respective field in accordance with the laws and regulations regarding the assessment, accreditation, and supervision of conformity bodies (hereinafter - the accredited laboratory);

19.5. the concentration of priority substances or dangerous substances detected in the wastewater as a result of measurements in receiving waters up- and downstream the discharge point of the wastewater. If the operator has performed the initial calculation of the mixing zone in accordance with Sub-paragraph 19.4 of this Regulation, then the concentration of priority substances or dangerous substances established in the receiving waters downstream of the mixing zone or at its boundary shall be indicated.

[4 April 2023]

19.¹ All operators who have, before 31 December 2022, obtained the permit for polluting activity which includes the discharge of wastewater into the environment or into a centralised equipment and pipeline system that ensures collection, discharge, and treatment of wastewater (hereinafter - the centralised collecting system) shall perform the monitoring of wastewater at the discharge point thereof for the relevant substances referred to in Annexes 1 and 2 to this Regulation, or for the priority substances or dangerous substances used or produced in the production process or formed in the adjacent processes in accordance with the deadlines specified in Paragraph 74 or 75 of this Regulation.

[4 April 2023]

19.² If the Service has received an application for obtaining the permit for polluting activity from the operator who discharges wastewater into the centralised collecting system or to external treatment plants, including in case of planning significant changes in activities, it shall inform the operator of the relevant centralised collecting system or treatment plants of the received application and send electronically the website address where the application is available.

[4 April 2023]

20. The Service shall include the following in the conditions of the permit:

20.1. a prohibition to discharge certain priority substances or dangerous substances, if it is necessary for the protection of the quality of surface waters;

20.2. discharge limits of priority substances and dangerous substances and the maximum permissible concentration in wastewater discharge after treatment;

20.3. [19 February 2013];

20.4. the requirement to use the methods of analysis for the monitoring of priority substances and dangerous substances and to conform to the procedures for the provision and control of the quality of results which ensure the fulfilment of the requirements laid down in the laws and regulations regarding the monitoring of surface waters, ground waters and protected territories and the drawing up of monitoring programmes for chemical monitoring of the water condition;

20.5. the term for fulfilment of the conditions of the permit referred to in this Paragraph, if the permit is intended for the present polluting activity;

20.6. a condition that the concentration of priority substances and dangerous substances in the aquatic environment, sediments, molluscs, crustaceans and fish may not significantly increase due to the polluting activity, and the requirements for monitoring in order to control the fulfilment of this condition;

20.7. the requirement to develop and submit a programme for the decrease of pollution to the Service within the period specified in the permit. An operator shall provide in the programme the most suitable techniques for the replacement, recovery and recycling of the relevant substances, if the pollution with the substances referred to in Annexes 1 and 2 to this Regulation is caused by sources to which discharge threshold values or limits cannot be applied;

20.8. the requirements for performance of monitoring referred to in Chapter VII of this Regulation;

20.9. the conditions for reviewing the permit on the basis of the results of the monitoring of wastewater and the initial calculation of the mixing zone performed by the operator.

[4 April 2023]

20.¹ The Service shall assess the mixing zone calculated by the operator in the surface waters downstream of the point discharge point of priority substances or dangerous substances.

[4 April 2023]

20.² The Service shall determine the mixing zone in the direct vicinity of the point discharge point, taking into account the following:

20.² 1. the programme for the decrease of pollution referred to in Sub-paragraph 20.7 of this Regulation and the possibilities for the application of the best available technical method;

20.² 2. the physical and chemical properties of the discharged priority or dangerous substances and hydrological conditions of the particular water body;

20.² 3. the concentration of polluting substances at the discharge point and the permit conditions for emission of polluting substances in a certain water body so that the mixing zone is proportionate in comparison with the total impact of such substances on the quality of the water body;

20.² 4. in the mixing zone the concentration of one or several substances referred to in Annex 1 or 2 to this Regulation may exceed the environmental quality standards laid down in the laws and regulations regarding water protection if it does not affect the compliance of the quality of the relevant surface water body with the abovementioned environmental quality standards outside the mixing zone, and the condition for significant non-increase in concentrations laid down in Sub-paragraph 20.6 of this Regulation has been fulfilled.

[4 April 2023]

20.³ If the Service establishes that the mixing zone specified in the application for obtaining the permit does not ensure fulfilment of the conditions referred to in Sub-paragraph 20.6 of this Regulation in the relevant water body outside the mixing zone, the Service shall, when issuing or reviewing the permit in accordance with the requirements of the laws and regulations regarding environmental protection, assess the size of the mixing zone downwards of the point pollution source and impose conditions for the reduction thereof.

[4 April 2023]

20.⁴ The Service may request a detailed assessment of the mixing zone if:

20.⁴ 1. if is required to assess the mutual impact of several wastewater discharges and to determine the combined mixing zones;

20.⁴ 2. irregular wastewater discharge is to be assessed;

20.⁴ 3. the results of the initial determination of the mixing zone indicate that outside thereof the concentration of one or more substances referred to in Annex 1 or 2 of this Regulation will exceed the environmental quality standards laid down in the laws and regulations regarding water protection.

[4 April 2023]

20.⁵ If it is required to assess the mutual impact of several wastewater discharges and determine the combined mixing zones, operators shall cover the expenses for a more detailed calculation of the mixing zone in proportion to the amount of pollution released into the environment. If expenses cannot be divided, the operators shall cover the costs in equal amounts.

[4 April 2023]

20.⁶ Information on the mixing zones downstream of the discharge point of priority substances or dangerous substances, the calculations associated with the determination thereof, and the conditions for reducing the mixing zone if the Service imposes them shall be included in the permit issued to the operator.

[4 April 2023]

20.⁷ The Service shall, once a year, aggregate information and inform the Centre of the designated mixing zones downstream of the discharge point of priority substances or dangerous substances in respect of which the conditions for reducing thereof have been imposed.

[4 April 2023]

21. In order to reduce surface water pollution caused by priority and dangerous substances, the Centre shall include relevant measures in the river basin district management plans and programmes of measures developed in accordance with the Water Management Law.

[4 April 2023]

IV. Discharge of Priority Substances and Dangerous Substances into the Groundwater

[27 July 2010]

22. The introduction of polluting substances (also priority and dangerous substances) into groundwater, except for the cases, if they leak through the soil or sedimentary rocks (hereinafter - direct discharge into groundwater), shall be prohibited, except the cases referred to in Paragraph 23 of this Regulation.

[27 July 2010]

23. The Service may allow direct discharge into groundwater if the quality of the groundwater does not deteriorate due to the discharge, the operator has performed a preliminary research, the operator has received a permit for the discharge of pollution and, in accordance with laws and regulations governing the use of subterranean depths, he or she has a licence for the use of subterranean depths for the following activities:

23.1. to introduce thermal water used for the acquisition of energy back into the same horizon from which it was obtained;

23.2. to introduce the water, which contains the substances which have formed as a result of research and the acquisition of hydrocarbons, in such geological structures from which the hydrocarbons or other substances have been evacuated, or in such geological structures, which due to natural conditions are not and will not be usable for other purposes, if the water entered contains only such substances which have been formed during the activities referred to previously;

23.3. to introduce the groundwater evacuated from working of quarries or civil engineering construction or for maintaining needs back into the groundwater horizons;

23.4. to introduce natural gas or liquid petroleum products gas for storage in geological structures, which due to natural conditions are not and will not be usable for other purposes;

23.5. to introduce natural gas or liquid petroleum products gas for storage in other kinds of geological structures, if it is specially necessary to ensure the gas stores and the introduction is carried out in such a way which eliminates the decrease of the quality of receiving groundwater now or in the future;

23.6. to introduce small amounts of substances into groundwater complexes for the purposes of scientific research, in order to characterise or protect groundwater or remediation performed therein, if more of the substances than would be necessary for the relevant purpose are not entered.

[4 April 2023]

24. The discharge restrictions laid down in this Chapter and the duty to take measures for restriction and prevention of pollution laid down in the laws and regulations regarding the procedures for the survey and quality criteria of groundwater resources shall not apply to the discharge of priority substances and dangerous substances into groundwater in the following cases:

24.1. the Service establishes that priority substances and dangerous substances are in such a small amount and concentration that the discharge thereof into the groundwater, including leaking through the soil or sedimentary rocks (hereinafter - the indirect discharge), does not prevent reaching the environmental quality objectives or quality standards determined and does not cause risk to deterioration of the condition of receiving groundwater either presently, or in future;

24.2. the Service recognises that discharge of domestic wastewater from separate buildings which are not connected to the centralised collecting system is insignificant and the abovementioned buildings are located outside the protection zones around the drinking water abstraction sites;

24.3. if discharge of polluting substances into the groundwater is the consequences of accidents or exceptional circumstances caused by natural process and it has not been possible to predict them and to prevent or reduce their impact;

24.4. polluting substances reach the groundwater due to raising of the water level of a groundwater body or artificial supplementation of stocks of groundwater which is carried out according to the conditions referred to in the permit issued by the Service;

24.5. the Service establishes that it is technically possible to prevent or restrict the discharge of polluting substances into the groundwater, to liquidate the polluting substances discharged in polluted soil or subterranean depths, or to otherwise control the getting of such substances in polluted soil or subterranean depths only by implementing measures which would increase threats to the human health or the environmental quality at large or would be incommensurately expensive;

24.6. if polluting substances are discharged into the groundwater by carrying out activities in surface waters, for example, by attempting to reduce the impact of flood or draught, or by managing waters and waterways (including cross-border). Such activities (including extraction, dredging work, movement and placing of sediments and drift material in the surface waters) shall be carried out in accordance with the laws and regulations regarding the procedures for cleaning and deepening of surface water bodies and port aquatic areas. The polluting substances which have been discharged into the groundwater as a result of the referred-to activities may not hinder the achieving of the environmental quality objectives, which have been laid down for the relevant groundwater bodies in accordance with the Water Management Law;

24.7. if polluting substances get into the groundwater in accordance with Paragraph 23 of this Regulation.

[19 February 2013; 4 April 2023]

24.¹ The conditions referred to in Paragraphs 23 and 24 of this Regulation may only be applied if the Service has recognised that efficient monitoring of supervision or another monitoring is ensured in the relevant groundwater body in accordance with the laws and regulations regarding the requirements for the monitoring of surface waters, ground waters, and protected territories and the development of monitoring programmes. The Service shall list the cases when the conditions referred to in Paragraph 24 of this Regulation were applied, and inform the Ministry of Environmental Protection and Regional Development thereof once a year.

[4 April 2023]

25. If an operator plans to dispose or store priority substances or dangerous substances prior to disposal and the referred to activities may cause indirect discharge into groundwater, as well as to perform other polluting activities which may cause indirect discharge into groundwater, a permit shall be received prior to performance of the referred to activities. The permit may be issued, if:

25.1. the indirect discharge does not affect active or decelerated water exchange zones, the waters from which are used for water supply;

25.2. the operator proves documentarily in the submission that all the necessary safety measures have been performed in order to prevent indirect discharge and pollution of groundwater, also an investigation of the groundwater pollution and hydrological conditions.

[27 July 2010]

26. The Service shall not issue a permit for the activities referred to in Paragraphs 23 and 25 of this Regulation if the river basin district management plans developed in accordance with the Water Management Law identify a significant and sustained increase in concentration of polluting substances, groups of polluting substances, or pollution indicators in the groundwater body (upward trend of pollution) which must be reduced, however, the abovementioned activities would cause additional discharge of the relevant polluting substances or groups of polluting substances and inadmissible spread of pollution, and also would endanger the abstraction of mineral water, drinking water, or water necessary for agricultural needs or cause harm to surface water or terrestrial ecosystems.

[4 April 2023]

27. Prior to issuing the permit for discharge into groundwater, the Service shall inform the Environment State Bureau if the discharge may cause cross-border pollution. The Environment State Bureau shall notify the competent authority of the relevant state.

[4 April 2023]

27.¹ When drawing up the conditions for a permit for the activities referred to in Paragraphs 23 and 25 of this Regulation, the Service shall take into account the following:

27.¹ 1. the chemical quality of the particular groundwater object and the environmental quality standards applicable thereto and threshold values of polluting substances, determined in accordance with the laws and regulations regarding the procedures for surveying of groundwater resources and quality criteria;

27.¹ 2. the significant and sustained upward pollution trends identified in the particular groundwater object and the conditions for prevention and reduction thereof which have been laid down in the laws and regulations regarding the requirements for the monitoring of surface waters, ground waters and protected territories and the drawing up of monitoring programmes.

[4 April 2023]

28. The following information shall be included in the conditions of the permit for the activities referred to in Paragraphs 23 and 25 of this Regulation:

28.1. the requirement to perform all the necessary precautionary measures in order to prevent the pollution of the groundwater of other horizons, other terrestrial ecosystems or water ecosystems with the substances discharged, taking into account the properties and concentration of these substances, characterisation of the receiving environment, as well as the proximity of water abstraction sites and drinking, thermal and mineral water abstraction sites;

28.2. the discharge limits for the discharged polluting substances;

28.3. the requirement to ensure groundwater quality monitoring in the horizon, where the polluting substances are discharged or are likely to be discharged and the horizons above in all the territory of the possible spread of pollution;

28.4. a regular inspection of the devices used for discharge of the polluting substances, also boring wells, leakproofness and safety;

28.5. the measures for changing the upward trend of pollution, if necessary.

[19 February 2013]

V. Discharge of Urban Wastewater

29. Highly sensitive territories, to which increased requirements for wastewater treatment apply, shall be determined, if the water body complies with one of the following criteria:

29.1. natural fresh water lakes and other fresh water bodies, as well as estuaries and coastal waters have become eutrophical - the enrichment of water by plant nutrients, particularly compounds of phosphorus and nitrogen, causing an accelerated growth of algae or higher forms of plant life, thus causing undesirable disturbance to the balance of organisms present in the water and to the quality of the water - or may become eutrophical in the nearest future unless protection measures are taken;

29.2. the concentration of nitrogen in surface water bodies of the fresh water intended for abstraction of drinking water exceeds or may exceed the quality standards specified in the laws and regulations regulating the surface water and groundwater quality, unless protection measures are taken;

29.3. more intensive wastewater treatment is required in order to achieve the environmental quality standards specified in laws and regulations.

[19 February 2013]

30. All the territory of Latvia is specified as a highly sensitive territory, to which high requirements for urban wastewater treatments apply, and the border of which match with the land borders of the Republic of Latvia.

31. The amount of pollution expressed in the population equivalents shall be calculated on the basis of the maximum amount of average weekly pollution, which reach the wastewater treatment plants (hereinafter - treatment plants) within a year under normal weather conditions. The load caused due to rain and other atypical conditions shall not be taken into account in these calculations. The amount of pollution expressed in population equivalents for planning purposes may be calculated on the basis of the number of inhabitants and enterprises for which a connection is planned, and depending on the water consumption characteristic to them and values of wastewater biochemical oxygen demand (BOD5). One unit of the population equivalent is the amount of pollution of organic substances which conforms to 60 g O₂ of biochemical oxygen demand per day.

31.¹ The requirements for a centralised collection and discharge of urban wastewater shall be determined for all populated areas or certain parts of the territory within the borders thereof where the number of inhabitants, population density and economic activity are sufficiently concentrated so that it would be economically justified to establish a centralised collecting network for the collection and discharge of wastewater from systems to wastewater treatment facilities or to the final point of discharge thereof into the environment (hereinafter - agglomeration).

[4 April 2023]

31.² A local government shall, by 30 June 2024 and thereafter at least once every seven years, assess the boundaries of agglomerations within its administrative territory, taking into account the technical and economic feasibility to expand the existing centralised collecting system or to construct a new centralised collecting system, and, where necessary, specify the boundaries of agglomerations on the basis of the following information:

31.² 1. population density in different parts of the agglomeration;

31.² 2. trends in changes in the population of the agglomeration over the last five years prior to taking the decision;

31.² 3. data from the register established in accordance with the laws and regulations regarding the management and registration of decentralised collecting systems;

31.² 4. the location, capacity, and technical condition of centralised collecting systems in the agglomeration, and also the location of decentralised collecting systems and operators of polluting activities and the load caused by pollutants;

31.² 5. the territorial local government spatial plan, including the building territories determined in accordance with the laws and regulations regarding water management services where centralised collecting systems are to be installed, and also the building regulations within the abovementioned territories.

[4 April 2023]

31.³ A territorial local government council shall take the decision to determine the boundaries of the agglomeration and submit, by 2 January 2025, to the Ministry of Environmental Protection and Regional Development the decision to determine the boundaries of the agglomeration, a justification thereof, and a cartographic material with the current boundaries of the agglomeration. If the territorial local government council takes the decision to change the boundaries of the agglomeration, the local government shall, within one month after taking of the relevant decision, submit to the Ministry of Environmental Protection and Regional Development the decision taken, the justification thereof, and the cartographic material with the current boundaries of the agglomeration.

[4 April 2023]

32. Centralised collecting systems shall be set up in agglomerations where the population equivalent is larger than or equal to 2000. A local government shall be responsible regarding setting up of the centralised collecting system.

[27 July 2010]

33. In agglomerations where the population equivalent is less than 2000, the relevant local government shall decide on the setting up of the centralised collecting system. The centralised collecting systems set up in such agglomerations shall comply with all the requirements of this Regulation.

[27 July 2010]

34. If the establishment of a centralised collecting system is economically unprofitable or will not improve the environmental quality, a decentralised collecting system or other type of installation (hereinafter - the decentralised collecting system) which ensures a similar level of environment protection as determined in the laws and regulations regarding the management and registration of decentralised collecting systems shall be used for collecting wastewater. Such a decision shall be substantiated with the results of technical economic research and environment research. If a decentralised collecting system is set up, the relevant local government shall ensure the regular collection of the wastewater collected therein and the utilised waste connected with it, and treatment in accordance with the requirements of this Regulation and other laws and regulations.

[4 April 2023]

35. If a centralised collecting system is set up in an agglomeration, the local government shall ensure regular collection and treatment of the wastewater collected in decentralised collecting systems and utilised waste connected with it, as well as perform accounting in accordance with this Regulation and the laws and regulations in the field of environmental protection.

[19 February 2013]

36. In designing, constructing and operating of centralised collecting system, the best technical solutions shall be used which do not cause excessive costs, taking into account:

36.1. the amount and content of urban wastewater to be collected;

36.2. the necessity to eliminate leakage;

36.3. the necessity to restrict surface water pollution, which is caused due to overload of the collecting system or in case of accidents during rainfall, in order that the environmental quality objectives specified for surface waters are observed. The permissible level of dilution and the frequency of overflow shall be determined in accordance with the construction standards of Latvia.

[19 February 2013]

37. Treatment technologies for wastewater collected in collecting systems are divided in the following way:

37.1. appropriate treatment - the use of such technologies and disposal systems which ensures the conformity of the receiving water body with the environmental quality requirements laid down for them and other conditions laid down in the laws and regulations regarding environmental protection;

37.2. primary treatment - physical or chemical wastewater treatment or another process in which the biological oxygen demand of the incoming wastewater load is reduced by at least 20 % before discharge and the total suspended solids of the incoming wastewater load are reduced by at least 50 %;

37.3. secondary treatment - the use of such technologies where generally biological treatment with secondary settlement or other processes are used which can ensure the conformity of the quality of wastewater discharged from treatment plants with the requirements specified in Table 1 of Annex 5 to this Regulation.

[19 February 2013]

38. In agglomerations, where the population equivalent is less than 2000, an appropriate treatment shall be performed for all wastewater collected in centralised collecting systems, as well as reduction of pollution in relation to the incoming load shall be ensured in accordance with Table 1 of Annex 5 to this Regulation.

[27 July 2010; 19 February 2013]

39. In agglomerations, where the population equivalent is from 2000 to 10 000, at least secondary treatment shall be performed for all wastewater collected in centralised collecting systems.

[27 July 2010; 19 February 2013]

40. In agglomerations where the population equivalent is more than 10 000, all wastewater collected in centralised collecting systems shall be treated more intensively than necessary, performing a secondary treatment and shall ensure the conformity of the wastewater with the requirements specified in Tables 1 and 2 of Annex 5 to this Regulation.

[27 July 2010]

40.¹ Where industrially manufactured wastewater treatment plants are used for the collection and treatment of wastewater within the territory of villages, towns, or cities, the treated wastewater is discharged into the environment, and the total capacity of these treatment plants is less than 5 m³ per day, the owner or possessor of the plants shall ensure at least secondary treatment of the wastewater, and also comply with the requirements laid down in Paragraph 9.¹ of Annex 5 to this Regulation.

[4 April 2023]

41. Treatment plants shall be designed, built, rebuilt, and operated:

41.1. in such a way that the place chosen for construction of a treatment plant would comply with all kinds of territorial planning;

41.2. in such a way that the treatment plants comply with the requirements specified in the construction standards of Latvia;

41.3. in such a way that the treatment plants would operate qualitatively under the climatic conditions of Latvia;

41.4. in such a way that it would be possible to take characteristic samples of influent, as well as treated wastewater before discharge thereof into the receiving waters, to keep a register and take samples in rainwater overflow chambers and emergency overflows;

41.5. taking into account fluctuations of the incoming load due to the seasonal work nature of treatment plants or load changes in different seasons;

41.6. evaluating all actually possible discharge sites (including the possibility of discharging the treated wastewater to another water body in the vicinity which is less sensitive to pollution) and the impact of the discharge at each site so that the selected discharge site would ensure as less harmful environmental impact as possible;

41.7. in such a way that the discharge site of urban wastewater treatment plants would be located as far from each other as possible, thus reducing the total impact on the relevant water body;

41.8. taking into account:

41.8.1. the objectives for using the water body;

41.8.2. the elements of the water body limiting eutrophication (nitrogen or phosphorus) and the sensitivity of the water body to pollution;

41.8.3. the efficiency of wastewater discharge getting mixed with waters of the water body;

41.8.4. the condition of the existing sewage system (including treatment plants), technical possibilities of introducing additional separation of the total nitrogen or total phosphorus and costs of such introduction and operation;

41.8.5. the possibilities of processing and further managing of wastewater sludge;

41.8.6. the possibility of discharging the treated wastewater to another water body in the vicinity, with less sensitivity to pollution;

41.8.7. the possibility to discharge the non-treated wastewater to another sewage system in the vicinity;

41.8.8. the solvency of inhabitants for introduction of additional requirements for more intense treatment of wastewater and ensuring operation of the relevant plants.

[19 February 2013]

42. Discharge of non-treated industrial wastewater, urban wastewater and sludge into surface waters or into the environment, as well as into the rainwater sewage system is prohibited.

[19 February 2013]

43. If industrial wastewater is discharged into a centralised collecting system or to external treatment plants, an operator:

43.1. shall enter into an agreement with the owner or possessor of the centralised collecting system or treatment plants. The contract shall specify the following:

43.1.1. the contracting parties;

43.1.2. the substances which are intended to be discharged, including all priority substances and dangerous substances that have been established in the wastewater when performing the monitoring referred to in Sub-paragraph 19.3 of this Regulation, or which the operator has intended to discharge;

43.1.3. the maximum amount of water and polluting substances which the plant may discharge;

43.1.4. the time period of the agreement;

43.1.5. the consequences in case of infringement of the terms of the contract for both parties;

43.2. shall perform pre-treatment of industrial wastewater ensuring that:

43.2.1. no harm occurs to the health of the personnel working with the centralised collecting system and treatment plants;

43.2.2. a centralised collecting system, treatment plants and technological equipment are not damaged;

43.2.3. the operation of treatment plants is not disturbed;

43.2.4. the discharge from treatment plants would not have an adverse effect on the environment and would not cause non-conformity of the receiving waters with the requirements of this Regulation and other laws and regulations;

43.2.5. the wastewater sludge would be possible to manage in accordance with the requirements of laws and regulations not causing harm to the environment;

43.2.6. the wastewater would conform with the conditions of the agreement referred to in Sub-paragraph 43.1 of this Regulation;

43.3. shall inform the operator of wastewater treatment plants and the Service of the concentration of priority substances and dangerous substances established in the previous calendar year as a result of the industrial wastewater measurements. Samples of industrial wastewater shall be taken at least twice a year (once every six months), so that the samples characterise the production process under its normal operating conditions.

[16 January 2007; 27 July 2010; 19 February 2013; 4 April 2023]

44. The operator of a plant shall attach a copy of the agreement referred to in Sub-paragraph 43.1 of this Regulation to an application for permit.

[16 January 2007]

45. If industrial wastewater, which contains biologically degradable substances and does not contain priority substances or dangerous substances, of the production sectors referred to in Paragraph 11 of Annex 5 to this Regulation is discharged directly into the surface waters, the following conditions shall be observed:

45.1. appropriate treatment shall be performed for wastewater from the undertakings the pollution caused by which is less than 4000 population equivalents ensuring the conformity of receiving water body with the environmental quality requirements laid down and other conditions laid down in the laws and regulations regarding environmental protection;

45.2. an operator shall apply the threshold values specified in Tables 1 and 2 of Annex 5 to this Regulation or use the best technical methods, choosing such type for discharge control, for which the most stringent requirements are specified, for the wastewater from the undertakings the pollution caused by which is equal to or higher than 4 000 population equivalents.

[16 January 2007; 27 July 2010; 19 February 2013]

46. An operator shall ensure useful utilisation of wastewater and sewage sludge (including the use of wastewater and sludge from wastewater in the fertilisation of the soil and improvement of the territories in accordance with the procedures specified in laws and regulations). A permit shall be received for the disposal of sewage sludge. Installations for the discharge of wastewater and the disposal of sewage sludge shall be set up in such a way that they decrease the adverse effect of wastewater and sewage sludge on the environment. The operator has the right to agree with other operators regarding the collection and disposal of sewage sludge at the places of deposition of other treatment plants. The operator shall notify the regional environmental board regarding such agreement within two weeks after entering into the agreement.

[4 April 2023]

47. Measures to reduce pollution caused by urban wastewater shall be included and implemented in the river basin district management plans and programmes of measures developed in accordance with the Water Management Law, specifying both deadlines for the implementation of the measures and the information on the necessary financing and its sources.

[4 April 2023]

VI. Discharge Threshold Values and Discharge Limits

48. Discharge threshold values for urban wastewater are laid down in Annex 5 to this Regulation.

[19 February 2013]

49. [19 February 2013]

50. [19 February 2013]

51. [19 February 2013]

52. The Service shall determine the discharge limits, taking into account the following:

52.1. the discharge threshold values laid down in Annex 5 to this Regulation and other laws and regulations, as well as the requirements connected with them;

52.2. calculation results acquired on the basis of the quality standards or principles laid down in the laws and regulations regarding surface water and groundwater quality;

52.3. the guidelines for the best available techniques;

52.4. the information regarding the discharge of pollution into the water or environment, the amount of pollution, including the discharged quantities of the substances referred to in Sub-paragraph 43.1.2 of this Regulation, and the planned control measures included in the submission of an operator, as well as regarding environmental impact on the receiving bodies of water;

52.5. the environmental quality objectives or quality standards laid down for a particular water body;

52.6. the water quality for the relevant water body and the sensitivity thereof to pollution, the information regarding other existing or expected sources of pollution, as well as the background concentration of the relevant substances;

52.7. the technical state of the treatment plants and possible improvement thereof without capital reconstruction;

52.8. the level of wastewater treatment in analogue wastewater treatment plants.

[4 April 2023]

52.¹ If, after reconstruction of wastewater treatment plants or construction of new plants, the discharge of wastewater is intended in a water body which has been determined as a risk water body due to a point pollution source in the laws and regulations regarding risk water bodies, the Service shall, upon assessing the significance of the impact of the substances specified in Annex 5 to this Regulation on such risk water body, determine the discharge limits for the relevant substances for any agglomeration or populated area which are no more than 25 % stricter compared to the requirements laid down in the abovementioned Annex.

[4 April 2023]

52.² The discharge threshold values expressed as the maximum permissible concentration may not exceed such threshold values which are expressed as the maximum permissible mass of the discharged substance in a certain period of time.

[19 February 2013]

52.³ The discharge threshold values shall be applied, taking into account the prohibitions and restrictions laid down in laws and regulations for production, importation, usage of and trade in dangerous chemical substances.

[19 February 2013]

53. If discharge threshold values for particular chemical substances or for discharge from specified production processes are not laid down in laws and regulations, the Service shall substitute them with other conditions ensuring equivalent protection of receiving waters and determine the discharge limits, taking into account the following:

53.1. the guidelines for the best available technologies;

53.2. discharge threshold values or environmental quality standards specified for substances with similar effect on the environment;

53.3. the quality of receiving waters - it shall in accordance with laws and regulations regarding the quality of surface water comply at least with water quality standards for Cypriniformes;

53.4. the specified environmental quality objectives and the quality standards laid down in the laws and regulation regarding the quality of surface waters and ground waters for particular chemical substances.

[4 April 2023]

54. The Ministry of Environmental Protection and Regional Development shall evaluate the necessity to change the discharge threshold values referred to in Annex 5 to this Regulation, if:

54.1. proposals from natural persons or legal persons have been received which are substantiated with the information regarding the effect caused by discharge;

54.2. changes are necessary taking into account the latest information regarding the effect of the polluting substances or advanced pollution treatment technologies;

54.3. it is necessary in order to achieve the environment quality objectives specified for receiving waters;

54.4. it is necessary taking into account international obligations of Latvia.

[16 January 2007; 19 February 2013]

55. The Ministry of Environmental Protection and Regional Development shall inform the natural and legal persons regarding the results of the evaluation not later than 12 months after the receipt of the proposal regarding necessity of the changes.

[16 January 2007; 19 February 2013]

VII. Monitoring and Control

56. The Service shall include in the permit the requirements for monitoring performed by the operator and shall determine the frequency of monitoring, taking into account the requirements laid down in this Regulation, the laws and regulations regarding the monitoring of surface waters, groundwater and protected territories, and in the laws and regulations regarding the monitoring of the environment and register of polluting substances, and also the nature and type of discharge, and the quality requirements for receiving waters.

[4 April 2023]

57. The operator, which discharges or plans to discharge priority substances or dangerous substances, shall develop and add the monitoring programme of the referred to substances to an application for the receipt of the permit. The procedures for the taking of samples, the procedures for specification of the amount of priority substances and dangerous substances used, as well as the procedures for performing of measurements for wastewater flow and other necessary measurements shall be described in the programme, taking into account the following conditions:

57.1. the samples are taken and wastewater flow is measured at the point where discharge threshold values are applied. If the referred to activities are performed at the point which is located before the point of application of discharge threshold values, the operator shall ensure:

57.1.1. that measurements at this point cover all the wastewater formed in the enterprise which may be polluted with the substances to be controlled;

57.1.2. the performance of regular analyses in order to prove that the results obtained at this point match with the amounts of substances discharged at the point of application of threshold values or are always greater than them;

57.2. samples collected within 24 hours in proportion to the wastewater flow shall be taken;

57.3. the amount of substance discharged within a month shall be calculated on the basis of the amount of substance discharged every day;

57.4. if it is not possible to specify the amount of separate dangerous substances used in the enterprise, a monitoring of substances shall be performed, which characterises the enterprise production capacity specified in the permit;

57.5. in monitoring of priority substances and dangerous substances the requirements in relation to the testing methods of the referred-to substances and the procedures for ensuring and control of the quality of results shall be conformed to, which have been laid down for chemical monitoring in the laws and regulations regarding the requirements for the monitoring of surface waters, ground waters and protected territories and the drawing up of monitoring programmes;

57.6. the measurements of wastewater flow shall be performed with a precision of ± 20 %.

[16 January 2007; 27 July 2010; 19 February 2013]

57.¹ Based on changes in the laws and regulations regarding the discharge of polluting substances into water, including changes in Annexes 1 and 2 to this Regulation, the Service shall request the operator to update monitoring information on discharge of priority substances and dangerous substances and develop a new monitoring programme on the basis of the results obtained.

[4 April 2023]

58. [19 February 2013]

59. In performing the monitoring of urban wastewater discharged from treatment plants, the operator shall follow the procedures and reference methods of analysis specified in Annex 5 and the criteria laid down in Annex 6 to this Regulation. Other methods of analysis may be used, if it is possible to achieve equal results.

[4 April 2023]

60. If the discharge of priority substances and dangerous substances can affect the territorial waters of other countries, the Service shall inform the State Environment Bureau. The State Environment Bureau shall notify the relevant states in order to agree on co-operation in the co-ordination of monitoring procedures.

[4 April 2023]

61. An operator shall submit to the Centre the monitoring data performed by the operator in compliance the laws and regulations regarding forms of environmental protection State statistics reports. The Centre shall compile and store the data received.

[16 January 2007; 27 July 2010]

62. In case of establishing any non-conformity of discharge with the conditions of the permit during the monitoring, the operator shall inform the Service and the Health Inspectorate thereof, ascertain the reasons for the non-conformity, and take the necessary measures to ensure conformity. The Service shall take the necessary measures to control the conformity of the discharge with the relevant requirements and prevent any reduction of the quality of the aquatic environment.

[4 April 2023]

63. The State environment inspectors shall perform the State control in order to check whether the wastewater containing priority substances or dangerous substances corresponds to the discharge limits specified in the permit and whether the wastewater discharged from treatment plants complies with the requirements specified in the permit. The necessary analyses shall be performed at an accredited laboratory.

[4 April 2023]

64. The State environment inspectors shall, at least once a year, verify compliance with the conditions specified in the permit issued to the operator.

[4 April 2023]

VIII. Provision of Information

65. The operator shall ensure that sampling and necessary analyses are performed by a an accredited laboratory. In accordance with the requirements specified in the permit, the operator shall provide the Service with the following monitoring data and information:

65.1. the conformity of the discharge of priority substances and dangerous substances, as well as other polluting substances (if discharge limits have been laid down for them in the permit) with the discharge limits laid down in the permit;

65.2. the conformity of the wastewater discharged from treatment plants with the conditions laid down in the permit;

65.3. the quality monitoring data of the receiving water body upstream and downstream of the point of discharge according to the requirements laid down in the permit;

65.4. the quantity, content, use, disposal and monitoring data of the sludge from the wastewater produced;

65.5. data of other types of monitoring according to the conditions laid down in the permit.

[4 April 2023]

66. In order to inform the public and State institutions regarding the protection of the aquatic environment against pollution caused by the discharge of priority substances, dangerous substances and urban wastewater, the Centre shall prepare information annually regarding the discharge of priority substances and dangerous substances, regarding the discharge of urban wastewater and the use of the sludge from wastewater and depositing in the territory of Latvia, as well as a summary regarding the results of the monitoring performed in accordance with this Regulation and ensure the availability of the referred-to information to the public in accordance with the requirements laid down in the Environmental Protection Law.

[27 July 2010; 19 February 2013]

67. The Ministry of the Environment in co-operation with the Centre shall provide the following information to the European Commission:

67.1. at least once every two years, upon request of the European Commission and in the form specified by it, a report on the discharge of urban wastewater and the use and disposal of wastewater sludge in the territory of Latvia, and also up-to-date information on the actions taken and planned to reduce the pollution caused by urban wastewater;

67.2. regarding the methods used for monitoring of urban wastewater.

[4 April 2023]

68. Information provided to the European Commission shall be freely accessible to the public.

IX. Closing Provisions

69. Up to the time when the requirement for the relevant installation to receive Category A or B permit comes into effect, the installation operator shall implement the requirements specified in the permit for use of water. If in the permit for the use of water all the requirements in effect specified in this Regulation are not mentioned, the operator not later than within a year after coming into effect of this Regulation shall submit to the regional environmental board a supplemented application for the receipt of the permit for the use of water.

[16 January 2007]

70. [4 April 2023]

71. The setting up of the collecting systems in agglomerations, where the population equivalent is above 100 000, shall be completed up to 31 December 2008, in agglomerations, where the population equivalent is from 10 000 - 100 000 - up to 31 December 2011, in all other agglomerations, where the population equivalent is above 2 000 - up to 31 December 2015.

[27 July 2010]

72. The requirements laid down in Paragraphs 38, 39 and 40 of this Regulation for urban wastewater treatment in agglomerations where the population equivalent is above 100 000, shall come into force from 31 December 2008, in agglomerations where the population equivalent is from 10 000 - 100 000, - from 31 December 2011, but in all other agglomerations where the population equivalent is above 2000 - from 31 December 2015. If the funding project is implemented in the agglomeration for construction of treatment plants or for reconstruction, the relevant requirements shall come into force after the full completion of the funding project.

[27 July 2010]

73. Paragraph 67 of this Regulation comes into force on 1 January 2004.

74. Operators who use the priority substances specified in Annex 1 and the dangerous substances specified in Annex 2 to this Regulation in their production process, or produce or form them in the adjacent process of production, and who discharge industrial wastewater into the centralised collecting system or to external treatment plants, shall provide the operator of wastewater treatment plants and the Service with the information specified in Sub-paragraph 43.3 of this Regulation by 30 June 2024 and thereafter by 30 June of each subsequent year.

[4 April 2023]

75. Operators who have obtained the permit for polluting activity which includes the discharge of wastewater into the environment shall provide the Service with the information specified in Sub-paragraph 19.3 of this Regulation, and if the mixing zone has been calculated, also the information specified in Sub-paragraph 19.4 of this Regulation within the following deadlines:

75.1. by 30 June 2025 - operators who, in accordance with the conditions of the permit, provide information on the discharge of priority substances or dangerous substances into surface waters in the official statistical reports on environmental protection or whose volume of discharged wastewater from any plant has been 1 million m³ per year or more in any of the last five years before coming into force of Paragraph 75 of this Regulation;

75.2. by 30 June 2026 - other operators who use or produce priority substances or dangerous substances in production processes and who discharge treated wastewater into surface water bodies;

75.3. by 30 June 2027 - operators of wastewater treatment plants who receive industrial wastewater.

[4 April 2023]

Informative Reference to the European Union Directives

[16 January 2007; 27 July 2010; 19 February 2013; 4 April 2023]

The Regulation contains legal norms arising from:

1) [4 April 2023];

2) [4 April 2023];

3) [19 February 2013];

4) [19 February 2013];

5) [19 February 2013];

6) [19 February 2013];

7) [19 February 2013];

8) [19 February 2013];

9) [19 February 2013];

10) Council Directive of 21 May 1991 concerning urban waste water treatment (91/271/EEC);

11) Directive 2008/105/EC of the European Parliament and of the Council of 16 December 2008 on environmental quality standards in the field of water policy, amending and subsequently repealing Council Directives 82/176/EEC, 83/513/EEC, 84/156/EEC, 84/491/EEC, 86/280/EEC and amending Directive 2000/60/EC of the European Parliament and of the Council;

12) Directive 2006/118/EC of the European Parliament and of the Council of 12 December 2006 on the protection of groundwater against pollution and deterioration;

13) Directive 2013/39/EU of the European Parliament and of the Council of 12 August 2013 amending Directives 2000/60/EC and 2008/105/EC as regards priority substances in the field of water policy;

14) Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy.

Prime Minister A. Bērziņš

Minister for Environmental Protection and Regional Development V. Makarovs

 

Annex 1
Cabinet Regulation No. 34
22 January 2002

[4 April 2023]

Priority Substances

No.	CAS number(1)	ES number(2)	Name of the substance(3)	Substance particularly dangerous to the aquatic environment(4)
1.	15972-60-8	240-110-8	Alachlor
2.	120-12-7	204-371-1	Anthracene	X
3.	1912-24-9	217-617-8	Atrazine
4.	71-43-2	200-753-7	Benzene
5.	Not applicable	Not applicable	Brominated diphenylethers	X(5)
6.	7440-43-9	231-152-8	Cadmium and its compounds	X
7.	85535-84-8	287-476-5	Chloroalkanes, C10-13	X
8.	470-90-6	207-432-0	Chlorfenvinphos
9.	2921-88-2	220-864-4	Chlorpyrifos (Chlorpyrifos-ethyl)
10.	107-06-2	203-458-1	1,2-Dichloroethane
11.	75-09-2	200-838-9	Dichloromethane
12.	117-81-7	204-211-0	Di(2-ethylhexyl)phthalate (DEHP)	X
13.	330-54-1	206-354-4	Diuron
14.	115-29-7	204-079-4	Endosulfan	X
15.	206-44-0	205-912-4	Fluoranthene
16.	118-74-1	204-273-9	Hexachlorobenzene	X
17.	87-68-3	201-765-5	Hexachlorobutadiene	X
18.	608-73-1	210-168-9	Hexachlorocyclohexane	X
19.	34123-59-6	251-835-4	Izoproturon
20.	7439-92-1	231-100-4	Lead and its compounds
21.	7439-97-6	231-106-7	Mercury and its compounds	X
22.	91-20-3	202-049-5	Naphthalene
23.	7440-02-0	231-111-4	Nickel and its compounds
24.	Not applicable	Not applicable	Nonylphenols	X(6)
25.	Not applicable	Not applicable	Octylphenols(7)
26.	608-93-5	210-172-0	Pentachlorobenzene	X
27.	87-86-5	201-778-6	Pentachlorophenol
28.	Not applicable	Not applicable	Polyaromatic hydrocarbons (PAH)(8)	X
29.	122-34-9	204-535-2	Simazine
30.	Not applicable	Not applicable	Tributyltin compounds	X(9)
31.	12002-48-1	234-413-4	Trichloro-benzenes
32.	67-66-3	200-663-8	Trichloro-methane (chloroform)
33.	1582-09-8	216-428-8	Trifluralin	X
34.	115-32-2	204-082-0	Dicofol	X
35.	1763-23-1	217-179-8	Perfluorooctane sulfonic acid and its derivatives (PFOS)	X
36.	124495-18-7	Not applicable	Quinoxyfen	X
37.	Not applicable	Not applicable	Dioxins and dioxin-like compounds	X(10)
38.	74070-46-5	277-704-1	Aclonifen
39.	42576-02-3	255-894-7	Bifenox
40.	28159-98-0	248-872-3	Cybutryne
41.	52315-07-8	257-842-9	Cypermethrin(11)
42.	62-73-7	200-547-7	Dichlorvos
43.	Not applicable	Not applicable	Hexabromocyclododecanes (HBCDD)	X(12)
44.	76-44-8/1024-57-3	200-962-3/213-831-0	Heptachlor and heptachlor epoxide	X
45.	886-50-0	212-950-5	Terbutryn

Notes.

⁽¹⁾ The number of the substance in the register of chemical substances Chemicals Abstracts Service.

⁽²⁾ EINECS (European Inventory of Existing Commercial Chemical Substances) number or ELINCS (European List of Notified Chemical Substances) number.

⁽³⁾ The substances characteristic of groups of substances shall be indicated for the chemical quality control of water under the respective environmental quality standards, unless otherwise specified.

⁽⁴⁾ X - a substance particularly dangerous to the aquatic environment the discharge and release of which is required to be averted by 22 December 2020. It is necessary to avert emissions and release of the substances No. 2, 5 and 28 until 22 December 2021, but of the substances No. 34, 35, 36, 37, 43 and 44 - until 22 December 2027.

⁽⁵⁾ Only Tetra, Penta, Hexa, and Heptabromodiphenylether (CAS-numbers 40088-47-9, 32534-81-9, 36483-60-0, 68928-80-3, respectively).

⁽⁶⁾ Nonylphenol (CAS No. 25154-52-3, EU No. 246-672-0), including isomers 4-nonylphenol (CAS No. 104-40-5, EU No. 203-199-4) and 4-nonylphenol (branched) (CAS No. 84852-15-3, EU No. 284-325-5).

⁽⁷⁾ Octylphenol (CAS No. 1806-26-4, EU No. 217-302-5), including isomer 4-(1,1',3,3'tetramethylbutyl)-phenol (CAS No. 140-66-9, EU No. 205-426-2).

⁽⁸⁾ Including benzo(a)pyrene (CAS No. 50-32-8, EU No. 200-028-5), benzo(b)fluoranthene (CAS No. 205-99-2, EU No. 205-911-9), benzo(g,h,i)perylene (CAS No. 191-24-2, EU No. 205-8838), benzo(k)fluoranthene (CAS No. 207-08-9, EU No. 205-916-6), indeno(1,2,3-cd)pyrene (CAS No. 193-39-5, EU No. 205-893-2) and excluding anthracene, fluoranthene, and naphthalene which are listed separately.

⁽⁹⁾ Including tributyltin-cation (CAS No. 36643-28-4).

⁽¹⁰⁾ This refers to the following compounds:

7 polychlorinated dibenzo-p-dioxins (PCDDs): 2,3,7,8-T4CDD (CAS No. 1746-01-6), 1,2,3,7,8-P5CDD (CAS No. 40321-76-4), 1,2,3,4,7,8- H6CDD (CAS No. 39227-28-6), 1,2,3,6,7,8-H6CDD (CAS No. 57653-85-7), 1,2,3,7,8,9-H6CDD (CAS No. 19408-74-3), 1,2,3,4,6,7,8-H7CDD (CAS No. 35822-46-9), 1,2,3,4,6,7,8,9-O8CDD (CAS No. 3268-87-9);

10 polychlorinated dibenzofurans (PCDFs): 2,3,7,8-T4CDF (CAS No. 51207-31-9), 1,2,3,7,8-P5CDF (CAS No. 57117-41-6), 2,3,4,7,8-P5CDF (CAS No. 57117-31-4), 1,2,3,4,7,8-H6CDF (CAS No. 70648-26-9), 1,2,3,6,7,8-H6CDF (CAS No. 57117-44-9), 1,2,3,7,8,9-H6CDF (CAS No. 72918-21-9), 2,3,4,6,7,8-H6CDF (CAS No. 60851-34-5), 1,2,3,4,6,7,8-H7CDF (CAS No. 67562-39-4), 1,2,3,4,7,8,9-H7CDF (CAS No. 55673-89-7), 1,2,3,4,6,7,8,9-O8CDF (CAS No. 39001-02-0);

12 dioxin-like polychlorinated biphenyls (PCB-DL): 3,3',4,4'-T4CB (PCB 77, CAS No. 32598-13-3), 3,3',4',5-T4CB (PCB 81, CAS No. 70362-50-4), 2,3,3',4,4'-P5CB (PCB 105, CAS No. 32598-14-4), 2,3,4,4',5-P5CB (PCB 114, CAS No. 74472-37-0), 2,3',4,4',5-P5CB (PCB 118, CAS No. 31508-00-6), 2,3',4,4',5'-P5CB (PCB 123, CAS No. 65510-44-3), 3,3',4,4',5-P5CB (PCB 126, CAS No. 57465-28- 8), 2,3,3',4,4',5-H6CB (PCB 156, CAS No. 38380-08-4), 2,3,3',4,4',5'-H6CB (PCB 157, CAS No. 69782-90-7), 2,3',4,4',5,5'-H6CB (PCB 167, CAS No. 52663-72-6), 3,3',4,4',5,5'-H6CB (PCB 169, CAS No. 32774-16-6), 2,3,3',4,4',5,5'-H7CB (PCB 189, CAS No. 39635-31-9).

⁽¹¹⁾ CAS No. 52315-07-8 refers to an isomer mixture of cypermethrin, alpha-cypermethrin (CAS No. 67375-30-8), beta-cypermethrin (CAS No. 65731-84-2), theta-cypermethrin (CAS No. 71697-59-1) and zeta-cypermethrin (52315-07-8).

⁽¹²⁾ This refers to 1,3,5,7,9,11-Hexabromocyclododecane (CAS No. 25637-99-4), 1,2,5,6,9,10-Hexabromocyclododecane (CAS No. 3194-55-6), α-Hexabromocyclododecane (CAS No. 134237-50-6), β-Hexabromocyclododecane (CAS No. 134237-51-7) and γ-Hexabromocyclododecane (CAS No. 134237-52-8).

 

Annex 2
Cabinet Regulation No. 34
22 January 2002

[4 April 2023]

Substances dangerous to the aquatic environment

No.	CAS number(1)	Name of substance
1.	7440-38-2	Arsenic and its compounds
2.	7440-66-6	Zinc and its compounds
3.	7440-47-3	Chromium and its compounds
4.	7440-50-8	Copper and its compounds
5.	309-00-2	Cyclodyene-class pesticides:
5.1.	60-57-1	aldrin (its isomer, isodrin)
5.2.	72-20-8	dieldrin
5.3.	465-73-6	endrine
6.	Not applicable	DDT total(2)
7.	50-29-3	para-para-DDT
8.	Not applicable	Polychlorinated biphenyls (PHB)
9.	107-13-1	Acrylonitrile
10.	Not applicable	Phenols (index of phenols)
11.	50-00-0	Formaldehyde
12.	127-18-4	Trichloroethylene
13.	79-01-6	Trichloroethylene
14.	135319-73-2	Epoxiconazole
15.	67747-09-5	Prochloraz
16.	107534-96-3	Tebuconazole
17.	60207-90-1	Propiconazole
18.	94-74-6	MCPA
19.	108-90-7	Chlorobenzene
20.	7803-57-8	Hydrazine hydrate
21.	106-89-8	Epichlorohydrin
22.	100-42-5	Styrene
23	56-23-5	Carbon tetrachloride
24.	Not applicable	Monoaromatic hydrocarbons (BTEX index, toluene, ethylbenzene, xylenes)
25.	Not applicable	Petroleum hydrocarbons (hydrocarbon C10-C40 index)

Notes.

⁽¹⁾ The number of the substance in the register of chemical substances Chemicals Abstracts Service.

⁽²⁾ DDT total comprises the sum of the isomers 1,1,1-trichloro-2,2bis(p-chlorophenyl)ethane (CAS number 50-29-3); 1,1,1-trichloro-2(o-chlorophenyl)-2-(p-chlorophenyl)ethane (CAS number 789-02-6); 1,1-dichloro-2,2bis(p-chlorophenyl)ethylene (CAS number 72-55-9); and 1,1-dichloro-2,2bis(p-chlorophenyl)ethane (CAS number 72-54-8).

 

Annex 3
Cabinet Regulation No. 34
22 January 2002

Discharge Threshold Values for Priority Substances and Dangerous Substances in Surface Waters

[19 February 2013]

 

Annex 4
Cabinet Regulation No. 34
22 January 2002

Reference Methods of Analysis to be Used for Monitoring

[19 February 2013]

 

Annex 5
Cabinet Regulation No. 34
22 January 2002

[4 April 2023]

Requirements for Urban Wastewater Treatment

I. Percentage of Reduction of Pollution

Table 1

Requirements for Waters Discharged from Urban Wastewater Treatment Plants in Respect of Biological Oxygen Demand, Chemical Oxygen Demand and Suspended Solids

No.	Parameter	Population equivalent	Concentration or treatment technology	Percentage of reduction of pollution	Reference method of analysis
1.	Biochemical oxygen demand (BOD5) at 20 °C (without nitrification)		appropriate treatment	-	Homogenised, unfiltered, undecanted sample. Dissolved oxygen shall be determined before and after a five-day incubation at 20 °C ±1 °C temperature, in complete darkness. Addition of a nitrification inhibitor
		200-2000	appropriate treatment	50-70
		2000-10000	25 mg/l	70-90
		> 10000	25 mg/l	70-90
2.	Chemical oxygen demand (COD)		appropriate treatment	-	Homogenised, unfiltered, undecanted sample. Use of potassium dichromate
		200-2000	appropriate treatment	50-75
		2000-10000	125 mg/l	75
		> 10000	125 mg/l	75
3.	Suspended solids - total amount	up to 10000	less than 35 mg/l	90	Filtering of a representative sample through a 0.45 µm filter membrane. Drying at 105 °C temperature and weighing
		10000 and more	less than 35 mg/l	90

1. The percentage of reduction of pollution (hereinafter - reduction) shall be determined comparing the amount of polluting substance in the treated wastewater with the amount thereof in the wastewater flowing into the treatment plant.

2. Instead of biological oxygen demand (BOD₅) another parameter may be used - total organic carbon or chemical oxygen demand, if a relationship can be established between the biological oxygen demand and the referred to parameter values.

3. In analysing discharges from lagooning, samples shall be filtered. The concentration of total suspended solids in unfiltered water samples shall not exceed 150 mg/l.

Table 2

Requirements for Discharges from Urban Wastewater Treatment Plants in respect of Total Phosphorus and Total Nitrogen

No.	Parameters	Population equivalent	Concentration or treatment technology	Percentage of reduction	Reference method of analysis
1.	Total phosphorus (Pkop)		appropriate treatment	-	Molecular absorption spectrophotometry
		2000-10000	appropriate treatment	10-15
		10000-100000	2 mg/l	80
		> 100000	1 mg/l	80
2.	Total nitrogen (Nkop)		appropriate treatment	-	Molecular absorption spectrophotometry
		2000-10000	appropriate treatment	10-15
		10000-100000	15 mg/l	70-80
		> 100000	10 mg/l	70-80

4. Total nitrogen (N_kop) means the sum of organic and inorganic nitrogen.

II. Reference Methods for Monitoring and Evaluation of Results

5. Flow-proportional or time-based 24-hour wastewater samples shall be taken at a specific point located in the outlet port of treatment plants and, if considered necessary by the Service, also in the inlet port. The degradation of samples between collection and analysis shall be minimised. Samples shall be taken throughout a year as frequently as specified in the permit.

6. The following samples shall be taken in agglomerations:

6.1. not less than 12 samples during the first year, if the population equivalent in an agglomeration is from 2 000-9 999. If the treated wastewater conforms to the requirements of this Regulation in accordance with Paragraph 7 of this Annex, then not less than four samples must be taken during the year. If at least one of the samples fails to conform to the requirements of this Regulation, not less than 12 samples shall be taken next year;

6.2. not less than 12 samples during the year, if the population equivalent in an is from 10 000 to 49 999;

6.3. not less than 24 samples during the year, if the population equivalent in an agglomeration is from 50 000 and more.

7. The treated wastewater shall be assumed to conform to the requirements of this Regulation, if analyses of samples thereof show the compliance of each parametric value specified and if:

7.1. the number of those samples, which fail to comply with the requirements specified in Table 1 of this Annex, do not exceed the number specified in Table 3 of this Annex;

7.2. in samples of wastewater taken under normal operating conditions, which fail to conform with the requirements, biological oxygen demand and chemical oxygen consumption demand differ from the concentration specified in Table 1 of this Annex not more than for 100 %. The difference between the concentration of suspended solids determined and specified in Table 1 may be up to 150 %;

7.3. the annual average values of concentration of total nitrogen and phosphorous complies with the value laid down in Table 2 of this Annex.

8. The total nitrogen concentration laid down in Table 2 of this Annex shall be the annual average value. Daily average value may be used, in evaluating the conformity of the nitrogen concentration with the requirements of this Regulation, if a greater load of pollution is not allowed in waters. Daily average value may not exceed 20 mg of total nitrogen (N_kop) to a litre of wastewater in any sample which is taken during a period of time when the temperature of the outlet wastewater from a biological treatment plant is 12 °C or higher. If due to the climatic conditions it is not possible to ensure the temperature of wastewater is at least 12 °C, the treatment of wastewater shall be performed by an incomplete treatment cycle in conformity with the requirements referred to in Paragraphs 5, 6 and 7 of this Annex.

9. In evaluating the conformity of wastewater samples with the requirements specified, parameter values caused due to heavy rain and other unusual situation shall not be taken into consideration.

9.¹ Samples of discharged wastewater from industrially manufactured wastewater treatment plants located within the territory of villages, towns, and cities where the treated wastewater of such plants is discharged into the environment, and the total capacity thereof is less than 5 m³ per day, shall be taken if an authority or person determined in accordance with the laws and regulations regarding the management and registration of decentralised collecting systems to perform supervision and control of such wastewater treatment plants have reasonable suspicions of non-compliance of the discharged wastewater with the requirements of this Regulation. In this case, the owner or possessor of the plants shall ensure that the wastewater sampling and necessary analyses are performed by an accredited laboratory. If the results of the analyses do not present excesses of the concentration of polluting substances, the sampling shall be repeated not earlier than after six months. If the results of the analyses present excesses of the concentration of polluting substances, the wastewater sampling and analyses shall be repeated after eliminating the deficiencies established in the operation of the plant and within the deadline determined by the authority or person exercising control. Expenses for the wastewater analyses shall be covered by the owner or possessor of the wastewater treatment plants if the results of the analyses present non-compliance of the wastewater with the requirements laid down in Paragraph 40.¹ of this Regulation. If the results of the wastewater analyses show that the requirements laid down in the respective Paragraph have been complied with, the expenses for the wastewater analyses shall be covered by the authority or person determined by a local government to perform supervision and control of such wastewater treatment plants.

Table 3

Maximum Number of those Samples which Fail to Conform with the Relevant Requirements (taking into account the series of samples taken during a year)

Series of samples taken during a year	Maximum number of samples which fail to conform with the relevant requirements
4-7	1
8-16	2
17-28	3
29-40	4
41-53	5
54-67	6
68-81	7
82-95	8
96-110	9
111-125	10
126-140	11
141-155	12
156-171	13
172-187	14
188-203	15
204-219	16
220-235	17
236-251	18
252-268	19
269-284	20
285-300	21
301-317	22
318-334	23
335-350	24
351-365	25

III. Typical Domestic Wastewater

Table 4

Parameters Characterising Typical Domestic Wastewater

Substance	Concentration (mg/l)
Biological oxygen demand (BOD5)	150-350
Chemical oxygen demand (COD)	210-740
Total suspended solids	120-450
Total phosphorus	6-23
Total nitrogen	20-80

10. Typical domestic wastewaters do not contain the dangerous substances referred to in Annexes 1 and 2 to this Regulation.

IV. Industrial Sectors

11. The requirements referred to in Paragraph 45 of this Regulation shall apply to the following industrial sectors:

11.1. processing of milk;

11.2. production of fruit and vegetable products;

11.3. production and bottling of non-alcoholic beverages;

11.4. processing of potatoes;

11.5. processing of meat;

11.6. production of beer;

11.7. production of alcohol and alcoholic beverages;

11.8. production of animal feed from products of plant origin;

11.9. production of gelatine and glue from the membranes, skin and bones of animals;

11.10. production of malt;

11.11. fish processing industry.

 

Annex 6
Cabinet Regulation No. 34
22 January 2002

[4 April 2023]

Procedures for Performing the Monitoring of Priority Substances and Dangerous Substances in the Discharge of Urban Wastewater Discharged from Treatment Plants

1. When planning and performing the monitoring of priority substances and dangerous substances in the discharge of wastewater, the operator of wastewater treatment plants shall take into account the following conditions:

1.1. in wastewater treatment plants where volume of discharged wastewater from any plant has been 1 million m³ per year or more in any of the last five years before coming into force of Paragraph 75 of this Regulation, the operator shall:

1.1.1. include in the monitoring the priority substances specified in Paragraphs 6, 20, 21, 23, 28, and 35 of Annex 1 to this Regulation and the dangerous substances specified in Paragraphs 2, 3, 4, 10, 24, and 25 of Annex 2 to this Regulation;

1.1.2. identify the largest manufacturing companies that discharge wastewater to the respective treatment plants, assess their type of activity and the volume of the received industrial wastewater;

1.1.3. include additionally in the monitoring the priority substances and dangerous substances the use of which is indicated in the permit for Category A or B polluting activity of the respective company, or which the company has established in the monitoring performed in accordance with Paragraph 74 of this Regulation, and also the priority substances and dangerous substances used or produced by companies of the relevant sector if the proportion of industrial wastewater discharged into the centralised collecting system exceeds 10 % of the total wastewater volume;

1.2. in wastewater treatment plants where the volume of discharged wastewater is less than 1 million m³ per year and which are already reporting on discharge of individual priority substances or dangerous substances, the operator shall:

1.2.1. include in the monitoring the priority substances and dangerous substances that have been controlled so far;

1.2.2. include additionally in the monitoring the priority substances and dangerous substances that are discharged into the centralised collecting system by companies of relevant manufacturing sectors that use or produce the abovementioned substances if the proportion of industrial wastewater discharged into the centralised collecting system is at least 10 % of the total wastewater volume;

1.3. in wastewater treatment plants that receive industrial wastewater the proportion of which is at least 10 % of the total wastewater volume, the operator shall include in the monitoring the priority substances and dangerous substances that can be discharged into the centralised sewage system by companies of relevant manufacturing sectors that use or produce priority substances or dangerous substances.

2. In addition to the conditions of Paragraph 1 of this Annex, operators of wastewater treatment plants shall include in the monitoring the priority substances and dangerous substances that have been established in the State environmental monitoring in the receiving surface water body, and shall determine poor chemical quality of water.

3. In order to ensure the credibility of monitoring results and reduce the potential impact of different factors on the monitoring results of urban wastewater, the operator shall, for one year, perform monitoring of the priority substances and dangerous substances selected in accordance with Paragraph 1 of this Annex, sampling at least once per quarter.

4. The operator may exclude priority substances or dangerous substances from further monitoring of wastewater, provided that all of the following conditions are met:

4.1. measurements have been taken for at least one year according to the frequency of monitoring specified in Paragraph 3 of this Annex;

4.2. all measurements taken for a specific substance have been below the limit of determination of the relevant testing method over the entire year;

4.3. there have been no significant changes in the manufacturing companies that discharge wastewater to be treated in the wastewater treatment plants, or there have been no changes in the activities of such companies which affect the volume and composition of wastewater;

4.4. the testing method employed is sufficiently sensitive and ensures that the limit of determination of the specific priority substance or dangerous substance is equal to or less than 30 % of the environmental quality standard value of the respective substance specified in the laws and regulations regarding water protection.

5. The operator shall, upon request of the Service, review and update the monitoring programme for priority substances and dangerous substances if there have been changes in the lists of priority substances and dangerous substances specified in the laws and regulations regarding water protection, in the volume and composition of wastewater received from manufacturing companies, and also taking into account information from the State environmental monitoring on those chemical substances that determine poor chemical quality of surface water in the receiving water body.

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