THOOTHUKUDI: The ambient air quality in Thoothukudi had improved substantially this year as per the data available in the Tamil Nadu Pollution Control Board (TNPCB).
In Thoothukudi, the ambient air quality stations are functioning at Raja Agencies, SIPCOT and AVM Building under National Air Monitoring Programme (NAMP) since 1988. While Raja Agencies and SIPCOT are industrial zones, AVM Building is a mixed zone. The station at Raja Agencies is closer to Thoothukudi Thermal Power Station (TTPS), NLC Tamil Nadu Power Limited (NTPL), private fertiliser plant, and VOC Port, whereas the SIPCOT station is adjacent to the Sterlite Copper.
Thoothukudi witnessed violent protest against industrial pollution in May, 2018 which led the state police to open fire at the protesters killing 13 on spot. The state government permanently shut downed Sterlite Copper on May 28, 2018 due to larger public interest.
According to an RTI reply, 438 industries functioning in Thoothukudi and its adjacent Ottapidaram taluks, includes 38 Red category (Large), 110 Red category (Small) and Orange category 287 industries.
Meanwhile, comparative data on air quality available for the years 2017, 2018 and 2019, had revealed that the air quality of Thoothukudi had improved dramatically.
TNPCB officials said that the air quality is measured based on Air Quality Index (AQI) derived from the sampling of air samples. The pollution causing SOx, NOx, PM and other pollutants contribute to the AQI. While the AQI value between 0-50 is good, 51-100 is satisfactory, 101-200 is moderate, 201-300 is poor and 301-400 is very poor and 401-500 is severe, they said quoting Central Pollution Control Board norms.
The air quality data recorded in August 2019 reveals that 70 per cent of the samples tested were 'satisfactory' and the AQI is below 100, whereas it was 29.17 per cent August 2018 and just 15 per cent in 2017. Besides, the air samples were 85 per cent moderately polluted in August 2017, while it was 70.83 per cent in 2018, and 29.16 per cent in 2019 during the same months.
The air quality index of the Raja Agencies station which was surrounded by thermal power plants also has improved gradually from 2.08 per cent of 'satisfactory' AQI in 2017, to 23.23 per cent in 2018, and 49.23 per cent so far in 2019.
Similarly, the SIPCOT station located amid an industrial hub, had recorded 36.26 per cent 'satisfactory' AQI in 2017, which has bettered to 61.38 per cent in 2018 and furthered to 81.53 per cent in 2019 so far.
As far as concerned about the residential area of Thoothukudi, the air quality has improved from 38.46 per cent of 'satisfactory' AQI recorded in 2017, to 61.29 per cent in 2018 and 77.27 per cent in 2019.
A senior officer attached to TNPCB wishing anonymity said that the intense vehicular movement, spillage during transportation of ores, coals, and other raw materials contribute largely to the pollution. The air quality is good during the months of October, November and December as pollutants are immediately washed away, he observed, The vehicular movements had quietly reduced after 2018, he said. The AQI has improved well due to intense road cleaning and removal of spillage using machinery, he added. Strict adherence to cover the coal and other raw material laden lorries using tarpaulin during transportation could achieve even better results, he further said.
According to the action plan of TNPCB, the air pollution concerns PM10 emission in Thoothukudi. The pollution is higher between March and August. The action plan has sought to reduce vehicular congestion, by increasing 5 per cent of government/private buses and construction of flyovers. Concerning the spillage, it has been suggested to identify road stretches with high dust generation and increase frequency of mechanised clearing of road and sprinkling of water on paved and unpaved roads.
In order to reduce emission during coal handling and transport, the stakeholding departments are instructed to provide windscreen at the wind carrier around coal stackyard, and dust suppression system and planting 10000 trees.
As coal-fired thermal plants contribute much to the emission of particulate matter, action plan suggested to adopt cleaner technology in coal-based Thermal Power Plants and stringent compliance by thermal power plants with respect to emission norms. The action plan had also suggested switching to power generation from existing coal-fired thermal plants to renewable sources like wind and solar plants before December 2023.
Health Statements for AQI categories
- Good (0-50) - Minimal impact
- Satisfactory (51-100) - May cause minor breathing discomfort to sensitive people
- Moderate (101-200) - May cause breathing discomfort to people with ling disease, heart disease, children and older adults
- Poor (201-300) - May cause breathing discomfort to people on prolonged exposure
- Very poor (301-400) - May cause respiratory illness
- Severe (401-500) - May cause respiratory even on healthy people and serious health impacts on people with lung/heart ailments.