The QUIC (Quick Urban & Industrial Complex) dispersion modeling system has been developed to provide high-resolution wind and concentration fields in cities. The Lagrangian dispersion model QUIC-Plume solves the Langevin equation and explicitly accounts for dispersion around buildings. As part of the development process for the code, several baseline test cases have been performed to ensure and document the model’s performance under idealized conditions. For this work, two simple test cases have been considered: uniform flow and a power law boundary layer flow. The two cases have been compared against classic Gaussian and non-Gaussian plume models respectively for releases at various heights. Grid refinement tests showed that in order to sufficiently match near source results, fine grid resolutions were necessary with the standard uniform grid model. To alleviate this problem and improve calculation efficiency, the code has been modified to incorporate embedded grids to allow for localized high-resolution calculations. The results show that QUIC-Plume reproduces both test cases quite well.