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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.

Intake fraction was determined in this study to provide insight into population exposures to PM10 that is effectively inhaled due to emissions of an opencast coal mine. We applied the CALPUFF model to a coal mine in Northern Colombia, which has 6 active pits with an annual production of 33.7 million tons. We estimated the intake fractions for 7 towns through the integration of dispersion model results over the population data. The resulting average intake fractions were between 6.13 × 10−9 and 3.66 × 10−8 for PM10. 62.4% of the intake fractions in the domain were calculated within a 23 km radius from the coal mine and coved 44.3% of the total population in this area. We calculated an estimate point for morbidity impacts using standard epidemiological assumptions. It is estimated that there were annually 105835 restricted activity days and 336832 respiratory symptom cases due to the direct impact of the opencast coal mining. These data also provide a framework for improved understanding of the effect of coal mining in Colombia.

This analysis seeks to evaluate the impacts of an open-pit coal mine located in the north of Colombia. It was used as the main tool CALPUFF, model Lagrangian, to determine the dispersion and transport of PM10 due to the emissions of the mining activities. The model was calibrated and validated with the environmental concentrations data of PM10 in 5 receivers. It was determined the contributions above of 45 km distances from sources. We use the concept of intake fraction, which is defined as the fraction of material or its precursor released from a source that finally is inhaled or ingested by a population. The results of the model show that the PM10 can be transported over long distances. to 50 km from the industrial zone of the mine, the average contribution of emissions of the mine can reach 9.12 μg/m3 and to 60 km contributions of 6.13 μg/m3. The modelling estimates that simulations of domain extending about 45 km from the source would only capture on average 54.83% of the total population intake fractions of PM10, and less for many geographic settings. The results show that the emission of PM10 is a problem of pollution on a regional scale. This analysis can serve as input to the competent authorities for better environmental management.

RESUMEN: Se determinaron las contribuciones de PM10 en al medio ambiente en una zona industrial minera en el norte de Colombia por actividades implicadas en el almacenamiento de 3.2 Mton carbón. Se utilizó como principal herramienta el software CALPUFF para determinar el aporte de PM10 durante 10 días de modelado durante un mes. Se midieron las concentraciones ambientales de PM10 en 5 receptores. Aunque las mayores emisiones se producen en horas diurnas, caracterizada por altos valores en la velocidad del viento y mayor insolación, la mayor receptividad de PM10 en las estaciones de mediciones se produce en horas nocturnas por la disminución de la altura de mezcla. Los resultados de la modelación muestran que las actividades implicadas en el almacenamiento de carbón pueden aportar un 14.5% de las concentraciones ambientales diarias en receptores ubicados a 16.2 km viento abajo de la fuente. ABSTRACT: The contributions of PM10 to the environment were determined in a mining industrial zone in northern Colombia for activities involved in storing 3.2 Mton of coal. As the main modeling tool the software CALPUFF was used to determine the contribution of PM10 for 10 days modeling during a month period. Ambient concentrations of PM10 in five receivers were measured. Although higher emissions occur during daytime, characterized by high values of wind speed and higher solar radiation, the greater receptivity of PM10 measurements stations occurred during night hours due to the decreasing the mixing height. The modeling results show that the activities involved in carbon storage can provide 14.5% of daily ambient concentrations at receptors located 16.2 km downwind from the source.

Fugitive material has been identified as the main source of air pollution, especially total suspended particulate (TSP) and particulate matter less than 10 micrometers (PM10) in open pit mining. The aim of this research was to estimate the concentration of PM10 and measure the impact of coal piles on nearby populations. The sources under consideration are three different areas for coal storing. All three areas are distributed along the mine with 14 piles with a total capacity of 3.2 Mton. Emissions were estimated and the contribution of PM10 for the activities of loading, unloading, hauling coal, tractor operations and wind disturbances on the surface of the coal piles using the emission factors suggested by EPA. The contribution to environmental receptors was determined with the dispersion model CALPUFF. Although higher emissions occur in solar hours, characterised by high values of wind speed and higher insolation, the greater receptivity PM10 measurements stations occur during the night hours by decreasing the mixing height. The model show that the activities involved in coal storage can provide 14.5% of daily environmental concentrations in receptors located 16.2 km downwind of the source, which showed that CALPUFF can be used for complex terrain and short distance from the source of emission.