KNOWN_ISSUES in CMAQv4.7.1 – 07 October 2010 Known issues in this release are: 1) When using the inline option for biogenic emissions, only one hour output timesteps are supported 2) DDM-3D is currently only operational with the "eddy" vertical diffusion module (DDM for the acm2 or acm2_inline modules will be available in the next release) 3) The gas phase oxidation of elemental Hg by NO3 has been determined to introduce a positive bias in the wet deposition estimates and results in lower than observed ambient elemental mercury concentrations when run for annual timeframe on a hemispheric scale. This reaction can be removed by setting the rate constant to zero in the multipollutant version of the model by editing line number 544 of the RXDT.EXT include file from + 3.5000D-15/ To + 0.0000D+00/ A clean build of the model is needed for this change to take effect.