Air Quality Analysis and Dispersion Modelling by Using AERMOD for Amonia (NH3) Parameters on Toll Roads in Makassar City

Abstract

Toll roads are alternative roads that are commonly used in urban areas to avoid congestion on local roads due to the increase in the number of vehicles during peak hours such as in the morning and evening. The existence of the Elevated Toll Road as a new icon in Makassar City has further increased the public’s desire to choose to cross the Toll Road. This situation causes changes in the volume of vehicles which are in the number of vehicle emissions that pass along the toll road. Ammonia (NH3) is a compound produced by vehicle emissions, but this has not been studied much because in general NH3 is produced from biological processes in the soil and processing factory waste. When ammonia enters the atmosphere and combines with the main pollutant it will form PM 2. The research was conducted at 9 points of the Makassar Toll Road including 3 points in Reformasi Toll Road and 6 points in Ir. Sutami Toll Road. The purpose of this study was to analyze the level of NH3 concentration in ambient air based on direct measurements using an impinger according to SNI 19-7119.1-2005 and to analyze the distribution pattern of pollutants using AERMOD software. The results showed that the concentration of NH3 pollutants on the Makassar Toll Road ranged from 5.99 g/Nm3 – 17.07 g/Nm3, while the results of NH3 dispersion modeling showed concentrations between 1.55 g/Nm3 – 13.3 g/Nm3. The concentration level of Ammonia (NH3) is still below the threshold value required by the National Ambient Air Quality Standards, which is 400 g/Nm3.