# The Water Framework Directive (Classification, Priority Substances and Shellfish Waters) Regulations (Northern Ireland) 2015, Regulation 11


For substances for which an environmental quality standard for sediment and/or biota is applied, the Department must, unless regulation 12 applies, monitor the substance in the relevant matrix at least once every year, unless technical knowledge and expert judgement justify another interval.

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Source: https://www.legislation.gov.uk/nisr/2015/351/regulation/11 (the official version)
Page: https://openlegislation.uk/water-framework-directive-classification-priority-substances-and-shellfish-waters-regulations-northern-ireland-2015/regulation-11
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.