Simulation of potential impact of air pollution from the proposed coal mining sites in Mui Basin, Kitui County

John Muthama; C. Kaume; Bethwel Mutai; John Kinyuru Ng'ang'a

John Muthama Department of Meteorology, University of Nairobi
C. Kaume Department of Meteorology, University of Nairobi
Bethwel Mutai Department of Meteorology, University of Nairobi
John Kinyuru Ng'ang'a Department of Meteorology, University of Nairobi

Keywords: Pollution, Wind rose, HYSPLIT, Trajectory, Dispersion, Exposure

Abstract

The potential for air pollutants transport, dispersion patterns and impacts within and around the Mui basin, Kitui County is simulated. The spatial-temporal distribution of air pollutants from the proposed coal mines was investigated using Hybrid Single Particle Lagrangian Integrated Trajectories (HYSPLIT) and dispersion analyses. The spatial distribution of wind patterns was investigated using wind rose to explain the observed air pollution distribution. The analysis was carried out for the dry and wet seasons of the study area namely: December, January, February (DJF), March, April, May (MAM), June, July, August (JJA) and September, October, November (SON) seasons. From the analysis, the season during which the exposure levels would pose much health threat was established based on frequency of winds blowing in certain direction and speed. By spatial analysis of the proximity of proposed mines and direction of dominant winds, areas most prone to pollution were delineated. The results showed that winds over the area were generally low and southerly. The residents to the northern and northwestern sectors would be at most at risk should the mining commence. Due to low wind speeds during January and the onset of JJA season, residents and workers at the mine would be affected adversely. The results may contribute to the design of effective control strategies to reduce impact of emitted pollutants.