Dynamics of PM pollution in the vicinity of the old municipal solid waste dumpsite.

The present study explored the effect of local meteorology on the dispersion of PM from a 30-year open municipal solid waste (MSW) dumpsite in Chennai, India. The spatial monitoring was conducted in and around the dumpsite to understand the impacts of dumpsite activities on the nearby residential area. Results showed that dumpsite activities are responsible for deteriorating local air quality. The 24-h average PM concentrations were 50, 43.7, and 34 µg m during stagnation, recirculation, and ventilation events, respectively. Spearman's correlation showed an inverse relationship between PM and temperature; wind speed indicated dispersion of fine aerosols. The observed inverse relationship between PM and relative humidity indicated the hygroscopic growth of fine aerosols in the study area. We used AERMOD to simulate the dispersion of 1-h, 8-h, and 24-h PM emissions from open waste burning in the dumpsite. The 1-h, 8-h, and 24-h simulated results showed the maximum concentration of 247, 136, and 53.4 µg m in the dumpsite, and concentration levels ranged between 50-60, 30-50, and 10-20 µg m were observed in the nearby residential area. The AERMOD predictions indicated that open waste burning could be a significant contributor to high PM concentration in an adjacent residential area of the dumpsite.