2 CASE-STUDIES OF DILUTION MODELS APPLIED TO THERMAL DISCHARGES

The United States Environmental Protection Agency models CORMIX2 and U M were used to predict the ambient temperature rises from thermal disc harges near Charlestown, Rhode Island, and Jamesport, Long Island, New York. Observations from two scaled model laboratory studies conducted at Alden Research Laboratories Inc. (ARL) were compared with temperat ure rise predictions from two numerical models. For the ARL diffuser a t Jamesport, both numerical models underestimated the observed tempera ture rises. In the Charlestown study, UM produced results that were in good agreement with the temperature rises observed, whereas CORMIX2 u nderpredicted observations but remained within the model's stipulated +/-.50% error. However, UM was unable to model the plume shape properl y, since it is primarily intended for alternating diffusers. The predi cted wastefield shapes of CORMIX2 were similar to those observed in th e laboratory but of greater surface area.