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Subsurface runoff generation
The model assumes that subsurface runoff is generated at the top of the clayey B-horizon by both infiltration excess and saturation excess processes. Subsurface saturation excess runoff (qsse) is generated on variable SOURCE Source areas, which are saturated due to the presence of a perched water table. Subsurface runoff by the infiltration excess mechanism (qsie) is estimated using a modified version of the catchment-scale infiltration capacity equation developed by Robinson and Sivapalan (1995). This equation relates the catchment scale infiltration capacity to the state of the infiltration store F and to the value of the water deficit in the groundwater store.
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Differences between LASCAM 2.0 and LASCAM for SOURCESource
The LASCAM hydrological routine was adapted and re-written as a C# plug-in for Source by the Water Science Branch, Department of Water, Western Australia. Some minor changes were made to the code to integrate the hydrology to the SOURCE FrameworkSource framework. These changes included:
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The code was tested for completeness using the nUnit test program and validated against the original LASCAM modelling results for the Nambeelup catchment, which was modelled as part of the Peel Harvey Nutrient Modelling project (Kelsey et al, 2010). 
Source Code
Source code available hereavailable https://bitbucket.org/ewater/source.communityplugins/src/master/LASCAM/.