# Air Quality Predictions through Mathematical Modeling for Iron Ore Mine Project
## 4 Modeling, Analysis, and Results  
### Model Simulations and Analysis  
To provide a detailed representation of particulate matter-concentration variations across the site and surrounding area, simulations were thus conducted using the high-resolution triple-joint frequency data available for every hour. These simulations covered a 20,000 m radius encompassing 16 directions emanating from the site, allowing for a thorough assessment of potential AQ impact. The simulations estimated incremental concentration values over the entire monitoring period, identifying the highest concentrations observed at any receptor point within a 24-hour timescale. The results were visualized using isopleths, which illustrated the distribution of suspended particulate matter (SPM) concentrations during mining activities (Figure 6). The isopleth simulation (Figure 6) depicted the spatial distribution of incremental SPM concentrations from the proposed mining operation, showing concentration contours of 15, 30, and 45 \(\upmu\)g/m\({}^{3}\). The concentric isopleths indicated a Gaussian dispersion pattern, with the highest pollutant levels near the emission source, gradually decreasing with distance. The peak incremental concentrations were observed within a 1000 m radius from the site, with values above 45 \(\upmu\)g/m\({}^{3}\). Beyond this radius, concentrations decreased, with values ranging from 30 to 45 \(\upmu\)g/m\({}^{3}\) up to 5000 m and further reducing to below 30 \(\upmu\)g/m\({}^{3}\) beyond 10,000 m. The model simulates a higher spread of SPM (15 \(\upmu\)g/m\({}^{3}\)) incremental concentrations in SW-SE directions and a lower spread in the other directions, reflecting the influence of prevailing wind patterns. The peak incremental Ground-Level Concentrations (GLCs) predicted by the model, the existing baseline levels of SPM and PM\({}_{10}\) measured during the pre-monsoon season, and the distances of monitoring locations are summarized in Table 5. The baseline SPM and the estimated SPM are also presented in Figure 7.  
Table 5 presents concentrations calculated under controlled emissions using the ISCST3 model, incorporating hourly wind data to simulate pollutant dispersion. The concentrations at receptor locations in surrounding villages exceed those in the Core Zone (single coordinate representing all the mining activities) due to the alignment with peak wind trajectories (as shown in Figure 6), which efficiently disperse pollutants from the mine. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Excavation** & **Loading of the Ore—OB** &
\begin{tabular}{c} **Loading of the** \\ **Ore—Core Zone** \\ \end{tabular} \\ \hline Ore production (million tons/year) & 0.5 & 0.5 & 0.5 \\ Total working days & 220 & 220 & 220 \\ Operational hours & 10 & 10 & 10 \\ Total operational hours & 2200 & 2200 & 2200 \\ Activity rate (t/h) & 227.27 & 227.27 & 227.27 \\ Uncontrolled emission rate (gm/t/h) & 0.0236 & 0.0236 & 0.0236 \\ Emission factor (gm/t) & 0.0236 & 0.0236 & 0.0236 \\ Influence area (m\({}^{2}\)) & 70,300 & 70,300 & 70,300 \\ Source emission rate in area (g/s/m\({}^{2}\)) & \(9\times 10^{-8}\) & \(2\times 10^{-8}\) & \(9\times 10^{-8}\) \\ Control efficiency (\%) & 90\% & 90\% & 90\% \\ Controlled emissions (g/s/m\({}^{2}\)) & \(9.3\times 10^{-9}\) & \(2.1\times 10^{-8}\) & \(2.1\times 10^{-8}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Iron ore-mine emissions calculated for the proposed IOM. The Core Zone, positioned away from peak winds, showed lower levels. Without control measures, incremental SPM could rise significantly in the Core Zone, causing substantial increases at other locations, highlighting the importance of dust control measures in protecting air quality and understanding pollutant dispersion dynamics. Figure 6: Isopleths of estimated incremental distribution of SPM in the vicinity of the IOM during mining activities. Figure 7: Baseline and predicted incremental SPM at different receptor locations.