Dispersion Modeling Reference Document for Restricted Hours of Operation has been Revised

The Iowa “DNR Suggested Methodology for Modeling Restricted Hours of Operation” has been revised. It is located in the dispersion modeling section of the Air Quality Bureau website at:

www.iowacleanair.com/prof/progdev/modeling.html

This document addresses how to characterize emission sources with restricted hours of operation in an air dispersion modeling analysis for both daily and annual operating restrictions. It elaborates on the guidance given in the “ Dispersion Modeling Guidelines” and provides several options depending on the needs of the facility.

This revision incorporates several minor changes and corrections. In addition, it offers another option for a facility to consider when modeling sources with daily operating restrictions.

Questions related to the new dispersion modeling reference document should be directed to Don Peterson, (515) 242-5153, Don.Peterson@dnr.iowa.gov.