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Hydrocarbon Spill Screening Model (HSSM) - Windows Version

The Hydrocarbon Spill Screening Model (HSSM) simulates flow of the light nonaqueous-phase liquid (LNAPL) and transport of a chemical constituent of the LNAPL from the surface to the water table; radial spreading of the LNAPL at the water table, and dissolution and aquifer transport of the chemical constituent.

The HSSM model is one-dimensional in the vadose zone, radial in the capillary fringe, two-dimensional vertically averaged analytical solution of the advection-dispersion equation in the saturated zone.

The model is based on the KOPT, OILENS and TSGPLUME models.

Version 1.20a
Release Date September 1997
Development Status General Release
Operating System Windows


HSSM Windows installation program (EXE)(1 MB)

US EPA. (1995) "The Hydrocarbon Spill Screening Model (HSSM), Volume 1: User’s Guide." Publication No. EPA/600/R-94/039a.

US EPA. (1995) "The Hydrocarbon Spill Screening Model (HSSM), Volume 2: Theoretical Background and Source Codes." Publication No. EPA/600/R-94/039b.

HSSM Volume II – Parameter Variation Data Sets (ZIP)(45 K)

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