Order No. 160 of the Ministry of Agriculture, Regional Development and Environment validating the Code of Good Agricultural Practices for the protection of waters against nitrate pollution from agricultural sources.

Code of Good Agricultural Practices for the protection of waters against nitrate pollution from agricultural sources establishes the following criteria: (a) the periods when the application of fertilizers in the soil is contraindicated; (b) the particularities of soil application of fertilizers on steeply sloping land; (c) the method of soil application of fertilizers on water-saturated, flooded, frozen or snow-covered land; (d) the conditions for applying fertilizers to the soil near water courses; (e) the construction and capacity of manure storage containers, including measures to prevent water pollution from rainwater and infiltration into underground and surface water of liquids containing manure and effluents from the stored plant material; (f) the conditions for applying chemical fertilizers and manure to the soil, which will maintain the loss of nutrients in the water at an acceptable level; (g) land use management, including the use of crop rotation systems and the ratio between the areas of land intended for perennial crops and those intended for annual crops; (h) maintaining an optimal amount of vegetation during rainy periods, which would absorb nitrates from soil, thus preventing water pollution with nitrates; and (i) the development of fertilizer application plans for individual agricultural households. The following criteria are used to identify waters affected or likely to be affected by nitrate pollution from agricultural sources: (a) fresh surface waters, used or to be used as a source of drinking water, containing or likely to contain nitrate concentrations higher than 50 mg NO3/l; (b) underground waters that contain or are likely to contain nitrate concentrations higher than the maximum permissible limit of 50 mg/l, if no protective measures are taken; and (c) fresh waters from natural lakes or other sources of fresh water (reservoirs, canals), coastal and marine waters are eutrophic or may become eutrophic in the near future, if no protective measures are taken. If larger amounts of fertilizers are applied than the plant needs, there is a risk that part of them (especially nitrates) will be drawn below the depth of the root front and directed to the phreatic aquifer, a fact that leads to the accumulation of nitrates in the underground water. The application of organic and/or mineral fertilizers is prohibited in the periods when the requirements of the agricultural crop towards nutrients are reduced, namely, when the time interval in which the average air temperature is lower than +5oC. This interval corresponds to the period when the nutrient requirements of the agricultural crop are reduced or when the risk of percolation/runoff to the surface is high. On soils periodically saturated with water or in flooded areas, the moment of application of fertilizers must be chosen, namely, when the soil has a humidity corresponding to the field capacity, thus avoiding losses of nitric nitrogen with percolation waters and drains.