No L 335/44 Official Journal of the European Communities 28. 11. 86 (Acts whose publication is not obligatory) COUNCIL COUNCIL DECISION of 24 November 1986 amending Decision 77/795/EEC establishing a common procedure for the exchange of information on the quality of surface fresh water in the Community (86/574/EEC) THE COUNCIL OF THE EUROPEAN COMMUNITIES, Having regard to the Treaty establishing the European Economic Community, and in particular Article 235 thereof, Having regard to the proposal from the Commission ('), Haviﬁg' regard to the opinion of the European Parli- ament (), Having regard to the opinion of the Eocnomic and Social Committee (%), Whereas, pursuant to Article 3 (6) of Decision 77/795/EEC (*), the Commission presented to the Council proposals with a view to improving the procedure for the exchange of information and harmonizing the methods of measurement with regard to the quality of surface fresh water ; Whereas, having regard to these proposals, the said Deci- sion should be amended with regard to the obligation to forward, and the date of forwarding, information to the Comrnission, the periods within which, and the method by which, the Commission communicates such informa- tion to the Member States and establishes a consolidated report ; whereas, in particular, Member States should be enabled to have at their diosposal, on request, annual statistics so as to allow them to monitor pollution levels in surface water; whereas the procedure which' the () OJ No C 321, 13. 12. 1985, p. 2. () OJ No C 88, 14. 4. 1986, p. 108. () O No C 189, 28. 7. 1986, p. 4. () OJ No L 334, 24. 12. 1977, p. 29. Commission must follow in assessing the effectiveness of the system should also be stipulated ; Whereas provisions should be envisaged for the intercali- bration of nationally applied methods of measurement with the reference methods of measurement; Whereas it is appropriate to include a new Article dealing with the minimum frequency of sampling and analysis of the parameters, with the possibility of reducing this frequency, under certain conditions, with the reference methods of measuring the parameters and with the condi- tions concerning sampling and the preservation of samples ; Whereas it is necessary to include in the Annexes an optional parameter and to fix reference methods of measurement which may be adjusted to take account of technical progress, HAS ADOPTED THIS DECISION : Article 1 Decision 77/795/EEC is hereby amended as follows : (1) Article 3 shall be amended as follows : (a) the following subparagraph is added to paragraph 3: ‘The descriptions of the methods referred to in Article 2 (2) (b) may be omitted if the methods are the same as those used in previous years, provided always that an explicit reference to any such omis- sion is made; ;