An air pollution data, submitted by Delhi International Airport Limited (DIAL) to Ministry of Environment, Forest and Climate Change (MOEF &CC) and Directorate of Civil Aviation (DGCA), to get Environment Clearance (EC) for the expansion of fourth runway raised questions, pertaining to various nature of data recorded in the same period.

Importantly, DIAL submitted different reports on air pollution in July, 2017 of aircraft operations in the vicinity of airports required to get EC from the authorities.

In a reply to an RTI querie about pollution data, submitted by DIAL, both MoEF and DGCA, shared different inputs about Nitrogen Oxide (NO2), Carbon Monoxide (CO), Sulphur dioxide (SO2),  Ozone (O3) and Particulate Matter (PM) 10 and 2.5.

For instance, DGCA mentioned values of CO 1.3 micro gram per cubic where as MOEF showed 1,158 micro gram per cubic for the same pollutant at same timeline while both the values shared by same source DIAL.  

Shocked environmentalists, aviation engineers have questioned the authenticity and source of variation in data collected by DIAL in July month of 2017.    

Anil Sood, a resident of Vasant Kunj, who filed the RTI, said, "The statutory authorities continue to be comatose about major pollutants despite norms in place and keep blaming diesel and petrol cars and make common citizens feel guilty about using cars. What a joke on honest tax payers."

It is important to mention here that no Environment Impact Assessment (EIA) has done before constructing runways. 

Pollution monitoring institutions — Delhi Pollution Control Committee (DPCC), Delhi Government and Central Pollution Control Board (CPCB), MOEF & CC both have denied any assessment on pollution emitted by aircrafts during takeoff and landing operations.

Interestingly, the Delhi Government, in a response to an RTI query, said that no such study has been undertaken by this (DPC) organisation. However, an ambient air monitoring station was installed and has been functional since 2011.