Gaseous Emissions During the Coal Mining Activity and Neutralizing Capacity of Ammonium.

This paper presents the simultaneous measurement of atmospheric concentration of gaseous NH, SO and NO, and particulate NH released from the mining activities of coal-mine area, Tirap colliery, Margherita (Assam). Gas samples were collected by impinger method and were analyzed colorimetrically. The vapor-phase concentration of NH, SO, and NO range between 4.7-40.03, 1.47-6.14, and 1.92-2.40 μg/m. The NH concentration in PM and PM ranges between 0.02-0.07 and 0.008-0.03 μg/m, respectively. Moderately high concentrations of NH and SO on the first day were due to the coal-burning activity near the sampling site, while the low concentration of NO is due to less vehicle density near the sampling point. All the observed concentrations are below than those reported for the urban areas and the prescribed limit fixed by National Ambient Air Quality Standard, India. Study indicates that ammonia is the major neutralizing agent for sulfate and nitrate ions present in the particulate matter during mining activities. [ABSTRACT FROM AUTHOR]