The Use of MM5-CMAQ for an Incinerator Air Quality Impact Assessment for Metals, PAH, Dioxins and Furans: Spain Case Study

Abstract

In this contribution we show the implementation of a modified version of MM5-CMAQ (Hutzell W.T., 2002) for carrying on an air quality impact analysis for installing an incinerator in the Basque Country Area (Spain). The modified CMAQ model (EPA USA, 2004) includes Poly-Chlorinated Dibenzo-p-Dioxins and Dibenzo-Furans (dioxins and furans). The model represents their cogeners as divided between gaseous and aerosol forms that exchange mass based on theoretical coefficients for gas to particle portioning. Modelled metals are included in CMAQ as part of the non-reactive aerosol component. Metals modelled are: As, Cd, Ni and Pb. In additional Benzo(a)pyrene (PAH) is also modelled. The model is implemented in a cluster platform in order to be used as a real-time air quality forecasting system by using the ON-OFF approach. The emissions of the projected incinerator in the ON run are incorporated by using the height of the chimney, the prescribed exit gas velocity, diameter of chimney and the limit emission values (worst scenario) prescribed in the Directive/2000/76/CE. The OFF run is done by using EMEP POP and PAH emission inventory. The system is mounted over one mother domain of 400 x 400 km with 9 km spatial resolution and two nesting levels: 100 km model domain with 3 km spatial resolution and 24 km with 1 km spatial resolution. All model domains have 23 vertical layers. The highest level is located at 100 mb. The architecture domain system is centered at the UTM coordinates assigned for the projected incinerator. EPER EU industrial emissions (May, 2004) of the surrounding large point industrial sources are used. Results are compared with the target values included in the proposal for a Directive of the European Parlament and of the Council (ENV 194 CODEC 439).