Determination of specific LNAPL volumes in soils having a multimodal pore-size distribution

Miguel A Alfaro Soto; Robert Lenhard; Hung K Chang; Martinus Th van Genuchten

doi:10.1016/j.jenvman.2019.02.077

Determination of specific LNAPL volumes in soils having a multimodal pore-size distribution

J Environ Manage. 2019 May 1:237:576-584. doi: 10.1016/j.jenvman.2019.02.077. Epub 2019 Mar 1.

Authors

Miguel A Alfaro Soto¹, Robert Lenhard², Hung K Chang³, Martinus Th van Genuchten⁴

Affiliations

¹ Department of Applied Geology and Center for Environmental Studies, São Paulo State University, UNESP, Rio Claro, SP 13506-900, Brazil. Electronic address: alfaro@rc.unesp.br.
² 13210 Palatine Hill, San Antonio, TX, USA.
³ Department of Applied Geology and Center for Environmental Studies, São Paulo State University, UNESP, Rio Claro, SP 13506-900, Brazil.
⁴ Department of Applied Geology and Center for Environmental Studies, São Paulo State University, UNESP, Rio Claro, SP 13506-900, Brazil; Department of Nuclear Engineering, Federal University of Rio de Janeiro, UFRJ, Rio de Janeiro, RJ, Brazil.

PMID: 30826639
DOI: 10.1016/j.jenvman.2019.02.077

Abstract

In this paper we present modifications to previously published models for determining the specific volume of non-aqueous phase liquids (LNAPLs) in the subsurface at and near the groundwater table following a spill or leak from the soil surface. The modifications account for porous media having multimodal pore-size distributions as is often the case with tropical soils. Data from the literature are used to show that the use of multimodal pore-size distributions can lead to significantly different subsurface LNAPL specific volume predictions and possible LNAPL recovery rates, compared to when only unimodal pore-size distributions are considered. Differences of up to 200% are possible when the dual-porosity nature of the pore system is ignored, which can yield erroneous estimates of the time needed to remediate LNAPLs from contaminated areas when conventional systems are employed.

Keywords: Free LNAPL; LDRM; Multimodal pore systems; Recoverable LNAPL.

MeSH terms

Groundwater*
Porosity
Soil
Soil Pollutants*

Substances

Soil
Soil Pollutants