AT123D Load Parameters

The AT123D load parameters contain information describing the mass release and timing. Initial Concentration Establishes the initial concentration within the contaminated groundwater plume. Initial Mass Load A single contaminant release within the groundwater plume at the start of the model run. Multiple Mass Loads (Load Release Rate) Application of a separate contaminant mass load for each monthly time step. This feature is used to link AT123D to the SESOIL vadose zone model. Instantaneous or Continuous Release Specifies if the release is instantaneous or continuous over a time step. The value is set to continuous when linked to SESOIL. This means the mass release takes a month. The instantaneous release is typically used to simulate an existing groundwater plume.