Mathematical simulation of the transport of isolanting mineral oil in the vadose zone considering the dielectric constant and the plasticity index

Published
2020-11-14
DOI: https://doi.org/10.14295/ras.v34i3.29501
Keywords: Transformer oil. Dieletric constant. LNAPL. Flow. Soil pollution. Óleo mineral isolante. Constante dielétrica. LNAPL. Fluxo. Contaminação do solo

Abstract

Accidents and failures of electrical equipment at power substations may result in infiltration of insulating mineral oil (OMI) into the soil leading to contamination. Mathematical modeling is an important tool to predict the impacts and to determine the response time of emergency actions. One of the most used software for this purpose is the Hydrocarbon Spill Screening Model (HSSM), distributed by the U.S. EPA. It is based on the equation of Nutting (1934) and it is capable of predicting OMI traveling in the vadose zone, but it does not consider (as for other models) the effect of the dielectric constant in determining the mobility of contaminants. Hence, the objective of the present study included an evaluation of the influence of the dielectric constant in the mathematical modeling of OMI and analyzed OMI spill simulations in five electric power substations with the Hydrocarbon Spill Screening Model (HSSM). The results indicated that, in expansive clay soils, the inclusion of the dielectric constant may represent an increase of up to three orders of magnitude in the hydraulic conductivity of the OMI, which influences contingency plans needed in case of spills.

How to Cite
Patricio, M. E. L. S., Schneider, M. R., Miotliński, K. Z., Giachini, A. J., & Quadros, A. M. (2020). Mathematical simulation of the transport of isolanting mineral oil in the vadose zone considering the dielectric constant and the plasticity index. Águas Subterrâneas, 34(3), 340–347. https://doi.org/10.14295/ras.v34i3.29501