The USEPA approved in July 2016 an update of CALMET and CALPUFF from V5.8.4 to V5.8.5. This update includes code changes described in Model Change Bulletin H and include fixes to bugs in the implementation of PRIME downwash, along with updates to eliminate specific compilation and list file errors. Three years later after the last update approved by the US EPA, this second revision is still falling short for odour dispersion modelling.
The CALPUFF Modeling System is a non-steady-state puff dispersion model that simulates the effects of time- and space-varying meteorological conditions on pollution transport, transformation, and removal. According to the US EPA CALPUFF can be applied for long-range transport and for complex terrain.
The technical recommendations in the design of stacks indicate that the emission at higher height, or a greater exhaust speed gases, decreases the impact in the surroundings. In fact, it is usual increases stack height in problematic sources.
For the industrial sector, in many occasions it is the directed sources that are the main route of emission of pollutants into the atmosphere. In these cases, the technical recommendations for minimizing the impact of industrial emissions on the environment indicate the chanelling of these emissions for dispersion at some height as a first step towards establishing possible corrective measures.