Agricultural Use of Sewage Sludge in Paraná State, Brazil: A Decade of National Regulation

Abstract

The agricultural use of sewage sludge brings benefits to soil and plant crops, but due to the possible presence of contaminating substances and pathogenic organisms it is necessary to follow the criteria for safe use for health and the environment. In Brazil, the Conama 375/06 Resolution established criteria and procedures for agricultural use of sewage sludge and Paraná is one of the few states in the country to use this alternative. This case study presents the management process and the results of the agricultural destination of the sludge in Paraná State, Brazil, from 2007, year in which the resolution came into force, to 2017. The management is carried out in two spheres of action: one in the context of the sludge management units (SMU) and another in the agricultural sphere. The sludge is provided free of charge to farmers, which reduces expenses with fertilizers and soil acidity correctives, resulting in economic and social benefits to the communities where it is used. However, from the year 2011 there was a reduction in the amount destined for agricultural use. The requirements of the national regulation make the process complex, overly bureaucratic and burdensome, requiring a review of its criteria.