Gurgaon: National Green Tribunal (NGT) has issued notice to Haryana govt and seven other respondents on a petition alleging prolonged non-compliance with sulphur dioxide (SO₂) emission norms at units 6, 7 and 8 of Panipat Thermal Power Station (PTPS). The petitioner has alleged that the plant has yet to install the required emission control system despite the issue being flagged in a Comptroller and Auditor General of India (CAG) report and the project being initiated years ago. TOI reported in July that PTPS was yet to install the mandatory SO₂ control system.NGT, in Tuesday’s order, recorded the allegations that PTPS had not installed a dry sorbent injection (DSI) system — air pollution control technology —and that SO₂ emissions were exceeding the applicable 600 mg/Nm³ limit. The matter has been listed for Jan 5, 2027. Besides the state govt, the respondents include Haryana State Pollution Control Board (HSPCB), power department, Central Pollution Control Board (CPCB), Commission for Air Quality Management (CAQM), ministry of environment, forest and climate change’s (MoEFCC’s) Chandigarh regional office, Haryana Power Generation Corporation Limited (HPGCL) and PTPS. The bench, headed by chairperson Justice Prakash Shrivastava, included expert member Dr Afroz Ahmad.The petition — filed by environmental activist Varun Gulati — says the compliance deadline has now been extended to Dec 31, 2027. However, it argues that installation of the DSI system could itself take 12 to 18 months, leaving limited time for installation and commissioning. The petitioner has also raised concerns over the wider impact of SO₂ emissions on Delhi-NCR’s air quality. The application states that SO₂ from coal-fired power plants contributes to the formation of secondary PM2.5 and can add to the regional pollution burden, particularly during winter. The application cites reported SO₂ emissions of approximately 5,656 tonnes from unit 7 and 5,504 tonnes from unit 8 in 2025 and says the two units were among the highest SO₂-emitting units within a 300-km radius of Delhi-NCR.The petition alleges that the units continue to operate without the required SO₂ control system despite earlier regulatory deadlines, the CAG finding and a tender process that has remained pending for years. The petition has cited emission data reported in July, according to which all three units recorded SO₂ concentrations above the applicable limit of 600 mg/Nm³ during 2024-25. Unit 6 recorded 763 mg/Nm³, unit 7 recorded 1,001 mg/Nm³ and unit 8 recorded 943 mg/Nm³, according to the figures reproduced in the petition.The petition seeks directions for time-bound installation, commissioning and operation of an effective SO₂ control system, including DSI or flue gas desulphurisation (FGD), as applicable, along with NOx emission control measures and periodic compliance reports before the tribunal. The NGT notice comes months after the issue was reported and the state pollution control board directed the power utility to expedite the project.PTPS is classified as a category-A power plant because of its location in the NCR, making sulphur-control measures applicable under the central pollution norms. The tender process had stalled for more than two years after bids were opened. The original compliance deadline of Dec 31, 2024 was subsequently extended to Dec 2027, but the system remained uncommissioned. The petition now filed before NGT says the delay goes back further. It cites CAG’s performance audit of HPGCL, which recorded that the corporation’s power plants were not meeting SO₂ and NOx emission norms. The audit recommended installation of pollution-control equipment to keep emissions within prescribed limits.The CAG report also recorded that PTPS units 7 and 8 — categorised as category-A units — were required to install emission-control equipment by Dec 2022 under the then applicable timeline. It noted that HPGCL had issued notices inviting tenders between April and Nov 2019 for installation of the DSI system for the two 250MW units. The petition says HPGCL later initiated a tender process covering PTPS units 6, 7 and 8, but the project remained pending before high powered works purchase committee since 2024. The petitioner submitted a representation to the authorities on June 25, 2026, seeking expeditious installation of the DSI system.
