Regulation 2(3) replaces existing regulation 3 of the 1996 Regulations with a new regulation setting out the duty in the Directive to identify nitrate polluted waters and to designate as nitrate vulnerable zones all known areas of land which drain into the identified waters and contribute to the nitrate pollution. The designation of nitrate vulnerable zones has to be reviewed every 4 years and revised and added to if necessary. To avoid having to amend regulation 3 every time there is a review n