A new version of AERMOD (dated 12345) was released this past month. A new version of AERMET (dated 12345) was also released along with the updated AERMOD model. Modifications to the new version of AERMOD are described in Model Change Bulletin #8 (dated 12/10/2012), which can be found on EPA's SCRAM website at the following link: http://www.epa.gov/ttn/scram/models/aermod/aermod_mcb8.txt
Its worthwhile to note that changes made to the model code (AERMOD 12345) have altered results obtained from the prior effective version of the model (AERMOD 12060). We have been in contact with NCDAQ and SCDHEC regarding the implementation of the new model during the transition period with regards to updated meteorological data processing and the like.