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Non-aqueous Phase Liquid (NAPL) Simulator

NAPL Simulator conducts a simulation of the contamination of soils and aquifers that results from the release of organic liquids commonly referred to as nonaqueous-phase liquids (NAPLS). The simulator is applicable to three interrelated zones: a vadose zone that is in contact with the atmosphere, a capillary zone, and a water-table aquifer zone. Three mobile phases are accommodated: water, NAPL, and gas. The three-phase k-S-P sub-model accommodates capillary and fluid entrapment hysteresis. NAPL dissolution and volatilization are accounted for through rate-limited mass transfer sub-models.

The numerical solution is based on a Hermite collocation finite element discretization. The simulator provides an accurate solution of a coupled set of non linear partial differential equations that are generated by combining fundamental balance equations with constitutive thermodynamic relationships.

This model is available in both two-dimensional and three-dimensional version.

Version 2.0
Release Date November 2010
Operating System DOS


US EPA. (1997) "NAPL: Simulator Documentation." Publication NO. EPA/600/R-97/102. Document Revisions (ZIP)(11 MB)

1-D File

NAPL 1-Dimensional DOS Tutorial (ZIP)(903 K)

2-D Files

NAPL 2-D DOS Source Code (ZIP)(345 K)

NAPL 2-D DOS Example Files 1 (ZIP)(221 K)

NAPL 2-D DOS Example Files 2 (ZIP)(239 K)

NAPL 2-D DOS Example Files 3 (ZIP)(224 K)

NAPL 2-D DOS Example Files 4 (ZIP)(269 K)

NAPL 2-D DOS Example Files 5 (ZIP)(289 K)

NAPL 2-D DOS Example Files 6 (ZIP) (447 K)

NAPL 2-D DOS Example Files 7 (ZIP)(296 K)

3-D Files

NAPL 3-D DOS Source Code (ZIP)(384 K)

NAPL 3-D DOS Example Files (ZIP)(305 K)