The aim of this research was the valorization of farms of different types and sizes located in 26 nitrate-vulnerable zones as to their specialization and intensity of production using a comprehensive evaluation method. The analysis was performed using survey data from 2010-2013 covering 164 Polish farms. The quality assessment was divided into two modules: production and environmental. The production module included the share of selected agricultural land and crop groups, consumption of mineral nitrogen and phosphorus fertilizers, consumption of industrial feeds, and the number of animals. The environmental module evaluated term of application of manures to fields, number of days mixed with soil, preparation of silage, management of domestic sewage, storage capacity for manure, and year of construction of plates, tanks, and cesspools. The points earned in individual farms ranged from 52 to 148. Statistical analysis, using the Ward method (Manhattan distance), allowed for seven separate groups of farms. The results showed that such elements as specialization, farm size, share of arable land and grassland, stocking density, mineral fertilizers, and industrial feed consumption were all important for the identification of potential hazardous farms. The average number of points for the individual farm groups ranged from 81 to 120.