54% of Delhi’s industrial units monitored online breach emission norms

More than half of Delhi’s industrial units whose emissions are monitored online have been found exceeding pollution limits, while nearly half of the installed air-emission monitoring systems are offline, The Indian Express has learnt, raising questions over how effectively industrial pollution is being tracked in the Capital.

According to Delhi Pollution Control Committee (DPCC) officials, of the 87 Online Continuous Emission Monitoring Systems (OCEMS) installed in Delhi’s industrial areas, 39 were offline as of Saturday. Of the remaining 48 transmitting data, at least 26 or 54% had been flagged for exceeding permissible emission limits.

The findings come as Delhi recorded an Air Quality Index (AQI) of 369 in the ‘Very Poor’ category on Saturday, a day before Diwali. Several areas recorded AQI levels above 400. The Air Quality Early Warning System has forecast ‘severe’ air quality for November 8 and 9.

The contribution of industry to Delhi’s air pollution burden is significant throughout the year. A 2018 TERI-ARAI source apportionment study had estimated that industrial emissions can account for up to 26% of the city’s annual air pollution load and play a major role in the formation of secondary particulate matter (PM).

The delay

Delhi has 30,672 industrial units in conforming industrial areas. Of these, 128 highly-polluting units are required to install OCEMS to allow authorities to monitor their emissions in real-time. However, only 87 have installed the systems.

A senior Commission for Air Quality Management in National Capital Region and Adjoining Areas (CAQM) official said several industries had cited financial difficulties for the delay. “They told us that the conflict in West Asia had disrupted supply chains and pushed up the cost of raw materials and equipment. So, this was an additional financial pressure on them,” the official added.

In a direction issued last month, the CAQM said industrial emissions were a major source of pollution in NCR. “Besides directly increasing PM concentrations, industrial emissions also contribute to the formation of secondary PM, adversely affecting ambient air quality. The impact of such emissions becomes prominent during the winter months, when adverse meteorological conditions restrict the dispersion of pollutants.”

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Reiterating the need for tighter surveillance, the CAQM directed industries covered under its order to operationalise OCEMS and enable real-time transmission of feeds from pan-tilt-zoom cameras. It has set a November 30 deadline to ensure the systems are fully operational.

Among other NCR states, meanwhile, Haryana has achieved near-complete coverage, with 907 units required to install or procure monitoring systems. Uttar Pradesh needs 648 such units, while it is 255 for Rajasthan.

Metal industries among major violators

Most of the flagged units in Delhi are involved in metal-processing activities, said officials. Of the 16 operational units engaged in metal-working, alloy manufacturing, foundry operations, brazing and die-casting, nine have been flagged for exceeding emission limits, they added.

These units are clustered across industrial hubs in Badli, New Mandoli, Narela, and Mayapuri. Smaller number of defaulting or flagged polluters are located in Bawana, Wazirpur, Gulabi Bagh, Mangolpuri, and North East Delhi’s Lawrence Road.

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Among these, Narela, Bawana, Wazirpur and Mayapuri are among the pollution hotspots identified by Environment department.

Badli and adjoining Samaipur Badli recorded the highest proportion of violations, with six of the seven operational OCEMS-equipped units transmitting data exceeding emission limits, said officials.

New Mandoli, meanwhile, had the highest number of operational monitoring systems, accounting for 14 of Delhi’s 48 online units. Six were flagged for violations. In Narela, two of the three online units exceeded emission limits, they added.

Individual flagged units were also reported from Wazirpur, Gulabi Bagh, Mangolpuri and Lawrence Road.

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High PM

According to the officials, PM or suspended particulate matter (SPM), was the most common pollutant found exceeding limits in these industrial units. Of the 26 flagged units, 24 had breached limits for PM. In 23 of these units, PM was the only pollutant being monitored.

Also, monitoring of gaseous pollutants was considerably more limited, they said. Among the 48 online air-emission entries, only two industrial facilities, apart from waste-processing plants, were monitoring pollutants such as sulphur dioxide, nitrogen oxides and hydrogen chloride.

The CAQM, which monitors OCEMS data from NCR states in real time, has also found problems with the data being transmitted by some industries, the officials added.

“We are monitoring the nature of the graphs emerging from these industries. Some show straight lines and no variations, which is unusual. This is how we are trying to identify if any manipulations have taken place,” a senior CAQM official said. “Issues have been reported in many cases where OCEMS have been installed, including prolonged offline status, flat-line data transmission, and technical contradictions like recording of pollutants continuing even when there was no flow of emissions.”