Directive 91/676/EEC
"It aims to reduce water pollution from nitrates used for agricultural purposes and to prevent any further pollution. It is closely linked to other EU policies which address air and water quality, climate change and agriculture.
EU countries must:
- designate as vulnerable zones all those draining into waters which are or could be affected by high nitrate levels and eutrophication. The designation is reviewed and possibly revised at least every 4 years to take account of any changes that occur;
- establish mandatory action programmes for these areas, taking into account available scientific and technical data and overall environmental conditions;
- monitor the effectiveness of the action programmes;
- test the nitrate concentration in fresh ground and surface water at sampling stations, at least monthly and more frequently during flooding;
- carry out a comprehensive monitoring programme and submit every 4 years, a comprehensive report on the implementation of the Directive. The report includes information on nitrate-vulnerable zones, results of water monitoring, and a summary of the relevant - aspects of codes of good agricultural practices and action programmes;
- draw up a code of good agricultural practice which farmers apply on a voluntary basis. It sets out various good practices, such as when fertiliser use is inappropriate;
- provide training and information for farmers, where appropriate." (http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=URISERV%3Al28013)