Dimapur, July 19 (MExN): Nagaland Pollution Control Board had been monitoring the ambient air quality of Dimapur for the last ten years in two stations located at Bank colony, and Dhobinala. Four air pollutants are monitored and analyzed viz., Nitrogen dioxide (NO2), Sulphur dioxide (SO2), Respirable Suspended Particulate Matter (RSPM) and Suspended Particulate Matter (SPM). The monitoring of pollutants is carried out for 24 hours (4 hourly sampling for gaseous pollutants (NO2 & SO2) and 8 hourly sampling for particulate matter (RSPM & SPM)).
In the year 2011, the average concentration of Respirable Suspended Particulate Matter is highest in the month of January in both the stations i.e. Bank Colony (317) with158 µg/m3 and Dhobinala (448) with 166 µg/m3 exceeding the permissible limit of 100 µg/m3. The lowest reading of Respirable Suspended Particulate Matter is recorded in the month of July with 20 µg/m3.
The gaseous pollutants i.e. Nitrogen dioxide (NO2) and Sulphur dioxide (SO2) are within the permissible limits in both the stations.The data for the year 2010 & 2011 shows that the Respirable Suspended Particulate Matter for both the stations (illustrated in the graphs) slight variations except in the month of January 2011 in bank colony. While in the case of Dhobinala station the variations during the year 2011 is higher compared to 2010.
Both Respirable Suspended Particulate Matter and Suspended Particulate Matter concentration increases in dry season because the bad road condition; raises dust by the vehicular movement or wind and particulate matters don’t settle down quickly. The increasing population and increased in number of automobiles and other small scale industries such as stone crushers, sand mahals, vulcanization, and improper waste management may be the other reasons for the increased air pollution.
The two records are taken from the permanent stations at Dhobinala and Bank colony, Dimapur City, and therefore variations will be there from colony to colony. However, the record definitely points to the fact that during dry season the air pollution, mainly dust particles are crossing the permissible limits and hence remedial measures such as improving the road, relocating polluting industries to outside the city limits, relocate sand mahals, better waste management, and maintaining green cover must be implemented to improve the ambient air quality of Dimapur city.
Issued by Nagaland Pollution Control Board
