This study had the objective of evaluating ground water table quality in an area cultivated with sugarcane and fertigated with stillage for a long time. Soil profiles were opened for identification and characterization of soil classes. The samples were collected from 19 observation wells distributed in six parallel transects at 100 m interval in an area of 12 ha. Three data collections were accomplished for water quality evaluation through determination of COD, BOD5, EC, TDS and physicochemical analysis of the stillage. Statistical analysis of COD indicated there were no significant differences among the soils (treatments), times or interaction between them during the 3-collection periods. Regarding BOD5, there were no significant differences among treatments or interaction but significant differences in time were observed. In relation to EC and TDS, both interaction and time responses were significant. After passing through the soil profile, COD, BOD5, EC, and TDS of in natura stillage decreased significantly. In general, the soil classes presented similar pattern in relation to the water table quality.
stillage; soil; fertigation; BOD5
