LNAPL Trasmissivity in contaminated areas of São Paulo State

Abstract

Soil and groundwater contamination by light, non-aqueous phase liquids (LNAPLs) is a frequent environmental issue, since these compounds are widely used in the industry and service sectors. For example, gasoline and other hydrocarbons derived from petroleum can result in NAPL contamination. The presence of these compounds in the environment can cause negative impacts related to human health, due to the soil contamination and vapor emissions. Besides that, LNAPLs are secondary sources of long term contamination. Moreover, the development of new techniques for remediation is even more important to solve that problem. A parameter which has been used to improve these techniques is the NAPL transmissivity, which quantify the LNAPL's mobility, considering it characteristics like density, and viscosity, and the characteristics of the contaminated area, like porosity, hydraulic conductivity, and soil heterogeneity, aiming an improved understanding of its behavior in the porous media. However, until now, this parameter is being used primarily in regions where the climate is temperate, and therefore there is a need to study NAPL transmissivity in soils submitted to tropical weather since the soil characteristics determine the contaminant's behavior. In addition, the composition of the fuel in Brazil is different, representing a high fraction of ethanol, for example. In this way, to assess the applicability of LNAPL Transmissivity in the State of Sao Paulo and subsidize new regulations it is necessary to evaluate and adapt the methodology for our conditions. (AU)