These Regulations establish and introduce an action programme for the protection of waters against pollution caused by nitrates from agricultural sources that is applicable to all farmers across Northern Ireland. The Regulations, among other things: impose certain obligations on controllers of agricultural holdings in respect of prevention of pollution and good agricultural practice (compliance with the Code of Good Agricultural Practice); establish closed periods for the land application of chemical fertiliser and organic manure; establish the manner of application and spreading of nitrogen fertiliser (including dirty water) regarding also minimum distances from waterways; place limits on the land application of nitrogen fertiliser; set out requirements for the storage of manure, silage, slurry, farmyard manure, poultry litter and dirty water; prescribe the requirements to be complied with for grassland holdings with an approved derogation from the measures governing the limits on land application of livestock manure, as provided for in paragraph 2(b) of Annex III of the Directive; and provide for the keeping of records and enforcement.