The draft Environment Impact Assessment (EIA) report prepared by the Telangana State Power Generation Corporation (TSGENCO) for seeking environmental clearance for the Yadadri Thermal Power Plant in Damarcherla of Nalgonda district is fraught with errors and inaccuracies, which could further delay the project, experts on environment contend.
An analysis on the draft EIA report by the Scientists for People, a collective of retired scientists, pointed out that the faulty assessment report has resulted in understatement of pollution.
The 829-page draft rushed through within six weeks after obtaining additional Terms of Reference as per the order by the National Green Tribunal, shows lack of diligence and professional integrity, alleged K. Babu Rao, a retired scientist from Indian Institute of Chemical Technology (IICT), who is part of the collective.
Flue gas stack
Major flaw in the draft report pertains to the Flue Gas Desulphurisation (FGD) and Nitrogen Oxides removal systems which have been made mandatory by the Ministry of Environment, Forests & Climate Change in all power plants commissioned in or after 2017.
“Wet Flue Gas Desulphurisation, which was mentioned in the report, requires a wet stack for handling condensate from the highly acidic flue gas. The design of the wet stack/chimney should be suitable to prevent the entrainment of condensate and rainout from the discharged flue. However, there is no mention of the wet stack, condensate collection, treatment, and safe disposal in the EIA report,” Mr. Rao said.
Instead, dry flue stacks of 7.6 metre diameter and 275 metre height have already built, which will be of no use when compared to the standards specified by the Central Electricity Authority (CEA) in 2017 for retrofitting the old and new power plants with FGD units. As per the standards, the maximum stack height is 150 metres for power plants over 500 megawatt in capacity.
“Considering the heavy expenditure to be incurred for construction of new stacks, the project is likely to be built without FGD units and end up polluting heavily, which defeats the very spirit of the NGT order to protect the Amrabad Tiger Reserve,” Mr. Rao said.
The faulty stack design will render the cumulative ground level concentrations presented in the EIA invalid, he said.
Coal consumption
Despite changing the coal from Grade 10 mentioned in the previous EIA to Grade 9 of the Singareni Collieries in the present draft, gross calorific value mentioned in the report was that of Grade 10 coal, which leads to questionable values of pollution load from coal combustion. Further, there are discrepancies even in the coal consumption values, between design station heat rate mentioned at 2109 kCal/kWh and the value of 2019 kCal/kWh used in coal consumption calculations, which would skew pollution levels.
The consultant indulged in ‘deception through omission’ by not including any impacts reported in the literature, Mr. Rao alleged and called the report ‘full of scientific dishonesty’.
“The draft EIA should be revised first with correct information before public hearing is held,” he demanded.
The earlier Environmental Clearance granted by the MOEF&CC was suspended by the NGT in 2022, which directed for the project to be reappraised, on the counts of change in coal consumption and the impact on the tiger reserve.
