Soil and Groundwater Remediation Proposal in an Aquifer of Venezuela by Hydrocarbon Transport Geostatistical Modeling

Abstract

In this paper, it is presented a remediation proposal for soil and groundwater remediation
proposal in an aquifer of Venezuela by hydrocarbon transport geostatistical modeling. The
contamination with hydrocarbons is occurring in the northern region of an aquifer of the
Carabobo State implying that the contaminants might be transported toward downstream of
the aquifer causing an impact on the water for human consumption and industrial uses. The
condition of the confined aquifer due to the alternating layers of low plasticity clay with well
graded sand has avoided that the hydrocarbons in the soil reach a concentration that exceeds
to the environmental regulation. For groundwater, the concentration of the hydrocarbons
such as TPH, TPH-GRO, Lead, Benzene, Toluene, Ethylbenzene, m.Xylene, o.Xylene and
MTBE is greater than to the environmental regulation. In most of cases, the spatial
prediction of hydrocarbons is explained by local polynomial interpolation of orders between
2 and 3, and in minor proportion by global polynomial interpolation of orders between 2 and
3. The gradient of the linear regression function varies between 0.34 and 0.94. The proposal
of remediation for hydrocarbons in soil and groundwater consists of applying of air injection
and vapor extraction, requiring an estimated air injection of 13153 m3
/d (323 cfm) and the
vapor extraction of 5075 m3
/d (125 cfm). The proposed wells for air injection (42) and vapor
extraction (19) in a Carabobo State aquifer separated each 100 meters and 150 meters,
respectively.