Surface Water Quality in Onshore E&P Activities in State of Espi´rito Santo, Brazil

This paper analyses which parameters may be in fact contributing for changing in water quality in Suruaca coastal lowland region, north of Espirito Santo, Brazil (Fig. 1). It is a low and plain area, with freatic level near surface, highly deforested, where there is a dominance of activities such as petroleum exploration and production, extensive cattle breeding and plantations of eucalyptus trees. Water quality monitoring surveys that have been carried out comprise 27 parameters at total, and some anomalies have been reported. From bibliographic search and interview with people who know the area, main economic activities in the region are defined, as well as raw materials utilized by them. Raw materials are analised by means of leaching, solubility, X-ray diffraction and X-ray fluorescence. Thus, it is tried to find links between parameters with anomalous concentrations and economic activities. Besides human sources, there are natural sources that are also contributing for changing the water quality of the region, but they are only mentioned in this paper. This paper shows that not all parameters analised need a continuity of monitoring, since both the characteristics of the economic activities placed in the studied area and the monitoring results give this away. On the other hand, there are other parameters that demand deeper researches, since they occur at concentrations higher than expected. For these latter parameters are related, as possible, the activities more likely of being contributing for its presence with concentrations above the allowable level. It is not possible to evaluate the origin of the anomalous concentrations for barium, lead and mercury.