A new version, Adaptive Puff Model 2 (APM2) of the Lagrangian adaptive plum
e model, APM, (Ludwig et al., 1989) has been tested around As Pontes power
plant, an elevated single source over complex terrain, during four represen
tative emission and meteorological dates in 1996. This 'closed-eyes' experi
ment has been performed in order to test APM2 around the As Pontes power pl
ant environment. Four dates were chosen by the power plant staff, and APM2
was run using the available emission and meteorological measurements. After
running the simulations, a specific comparison based on the available grou
nd-level concentration data was planned and applied, in order to obtain an
evaluation of the new features included in the model, specifically new plum
e rise and plume growth equations. The observed maximum plume impact distan
ce from the source and maximum ground-level concentration, calculated by in
terpolation from the concentration measurements, are the evaluation paramet
ers. Final results show that the difference between estimated and observed
maximum impact distance reaches 10 km in some cases. In addition, APM2 over
estimates the maximum ground-level concentration in all dates tested.