The Commission for Air Quality Management in NCR and Adjoining Areas (CAQM) has issued Show Cause Notices to six coal-based thermal power plants (TPPs) located within a 300-km radius of Delhi for non-compliance with mandatory biomass co-firing norms. The action follows a detailed review of compliance for FY 2024–25 based on data submitted by the Ministry of Power.Under the Environment (Utilisation of Crop Residue by Thermal Power Plants) Rules, 2023, all coal-based TPPs are required to co-fire a minimum 5 per cent blend of biomass pellets or briquettes made from crop residue, with a threshold of over 3 per cent prescribed for FY 2024–25 to avoid the imposition of environmental compensation (EC). These provisions aim to promote ex-situ management of paddy straw, curb stubble burning and reduce air pollution in the NCR and adjoining areas.CAQM found that biomass co-firing levels at the identified plants remained well below the mandated limits during the review period. Consequently, Show Cause Notices proposing EC have been issued to Talwandi Sabo Power Limited (Vedanta) in Punjab (Rs 330.02 million), Panipat Thermal Power Station in Haryana (Rs 80.98 million), Deenbandhu Chhotu Ram Thermal Power Station, Yamunanagar (Rs 60.69 million), Rajiv Gandhi Thermal Power Plant, Hisar (Rs 50.55 million), Guru Hargobind Thermal Power Plant, Lehra Mohabbat (Rs 40.87 million), and Harduaganj Thermal Power Station in Uttar Pradesh (Rs 20.74 million). The total proposed EC across the six plants amounts to approximately Rs 610.85 million.The Commission noted that despite repeated statutory directions, including Direction No. 42 issued in September 2021, and continued monitoring through reviews and inspections, compliance has remained unsatisfactory. In early 2024, notices under Section 14 of the CAQM Act, 2021 were also issued to persistently non-performing plants.The concerned TPPs have been directed to submit written explanations within 15 days, failing which further action will be initiated under the CAQM Act. CAQM reiterated that strict enforcement of biomass co-firing norms is essential to reduce air pollution and ensure sustained compliance across the sector.