Using the European rule Article 19, a policy to control nitrate contamination resulting from agricultural production is coming into action in the French county Yonne. The farmers are requested to change their farming methods. The research is aiming to identify farmer's attitude about this. The theoritical approach is based on the social representation concept. Three objects have been studied : farming methods, pollution caused by nitrates, environnemental agricultural problem. Following an analyse of the consensus, différents behaviours have been drawn out by a gradual typology. This allows us to conclude on the fragile parts of the policy.
