monitoring and assessment of pollutants resulting from bench-blasting operations

nitrogen oxides and carbon monoxide gases together with dust are known as the major pollutants arising during the blasting operations using the ammonium nitrate-fuel oil (anfo) explosive at the sungun surface mine, located in the northwest of iran. the pollutants were monitored during some blasting operations at the mine. it was concluded that the gases and dust clouds initially went up to the peak height, and were then released in the direction of wind flow. a large volume of the pollutants in the form of clouds, which fell at the mine and its surrounding environment, was usually discharged again to the atmosphere due to other mining activities. it was also found that all kinds of pollutants at the mine imposed high risks to the ecosystem of the mine. the maximum concentration of the pollutants belonged to the particles with a size more than 20 microns. the southern part of the mine had a more potential vulnerability than its northwestern part, according to the monthly wind rose diagrams of sungun. the investigations carried out at the mine and its surrounding environment have indicated that the current traditional blasting operations have discharged a considerable amount of pollutants into the mine and the arasbaran protected area. the current blasting pattern should be improved, especially through analyzing and changing the stemming materials and length, in order to provide a safe environment for the ecosystem of the mine and the arasbaran area.