PERCOLATE QUALITY IN SOIL CULTIVATED WITH APPLICATION OF WASTEWATER FROM SWINE SLAUGHTERHOUSE AND DAIRY PRODUCTS
ABSTRACT The objective of this study was to evaluate the quality of the percolate in soil columns cultivated with Tiffon-grass 85 under different wastewater rates from swine slaughterhouse and dairy. The experiment was conducted at the Department of Engineering at the Federal University of Lavras, in PVC columns with 0.30 m of diameter and 1.2 m deep, filled with Dark Red Latosol cultivated with Tifton-grass 85. The treatments consisted of a (AQT0) control with recommended chemical fertilization for Tifton-grass 85 (300 kg ha-1 year-1 of N), and four doses of SSW and DPW (100, 200, 300 and 400% of the recommendation) in a CRD with 3 replications. The samples of percolated were collected and characterized weekly. The treatments of highest dosage have obtained COD, after 120 days, of 47.7 mg L-1 (AAT3) and 38.6 mg L-1 (AAT4). Although nitrate concentrations were elevated on the earlier months, the greater assimilation of nutrients by the Tifton-grass 85 and the reduction of the mineralization of organic material resulted in lower nitrate concentrations of 10 mg L-1.