Environmental impact of fly ash contaminated soil of the surrounding area of Kolaghat thermal power station in West Bengal, India

Fly ash is a byproduct of coal combustion in thermal power plants posing significant environmental concerns owing to its possible to pollute soil, air, and water. The second largest coal-based thermal power station in West Bengal (India) is Kolaghat Thermal Power Station (KTPS) which generates large quantities of fly ash, often deposited in the surrounding environment over a long period. This study investigates the physicochemical and microbial properties of soils contaminated by fly ash of KTPS near the power station to assess its impact on soil quality and agricultural sustainability. The current study indicated that the levels of heavy metals (HMs) like Pb, Cr, As, and Fe in fly ash-contaminated soils (FCS) were notably greater than those in the control soil. Physiochemical characteristics like pH, bulk density (BD), electrical conductivity (EC), total organic matter (TOM), water holding capacity (WHC), and NPK content differed concerning control soil affecting the nearby agricultural land. Colony-forming units were used as a common indicator of microbial biomass. Microbial activity was changed with the alteration of different physicochemical properties of the soil. It was found that bacterial activity was higher in all of the collected FCS samples. So, the findings provide valuable insights into the long-term consequences of fly ash deposition and suggest strategies to mitigate environmental damage and to promote sustainable agricultural practices.