Publications

Arregoces, HA; Rojano, R; Restrepo, G (2021). Effects of Lockdown due to the COVID-19 Pandemic on Air Quality at Latin America's Largest Open-pit Coal Mine. AEROSOL AND AIR QUALITY RESEARCH, 21(8), 200664.

Abstract
Particulate matter (PM) is the main pollutant produced by open-pit mining operations, and its emission into the atmosphere is strongly associated with adverse health effects in the surrounding communities. The objective of this study was to evaluate the effects of the COVID-19-related lockdown on the PM concentrations in the North, Central, and South Zones of Cerrejon, Colombia, the largest open-pit coal mine in Latin America. To compare the levels before and during the emergency shutdown, we analyzed both the ground-based daily PM10 and PM2.5 data and the satellite (Terra/Aqua MODIS)-based daily aerosol optical depth (AOD) values from March 6 through April 13, 2020. The average PM10 concentrations in the North and South Zones, in contrast to those observed at other global monitoring sites, increased by 13-38% and 4-7%, respectively, although they decreased by 26-31% in the Central Zone, between the pre-lockdown and lockdown periods. Furthermore, during the latter, the daily PM2.5 levels in the South Zone rose by up to 43%, and we found higher AOD values (>= 0.4) over the Central and South Zones as well as significant AOD-contributing loads upwind and downwind of the coal production pits. Finally, the increases in humidity and temperature (>= 3.5% and > 0.3 K, respectively), decrease in planetary boundary layer height (>= 0.11 km), wind field variability, and rural biomass burning events shaped the spatial-temporal behavior of the PM in this region, and changes in meteorology and external sources nearly offset the reduction in emissions from mining activities. These results establish a baseline for developing future regulations and mitigation plans.

DOI:
10.4209/aaqr.200664

ISSN:
1680-8584