Extensive coal mining activities result mine spoil generation dumped in form of overburdens altering biogeochemical cycles and land degradation. Mine spoil generated after post-mining activities associated with heavy metal toxicity inhibit microbial growth. Being deficient in available nutrients due to lack of biologically rich topsoil, mine spoil represents a disequilibrated geomorphic system and poses problems for revegetation and restoration of coal mine spoil. Mine spoil genesis influencing ecosystem functionality demands physicochemical characterization and spatial distribution of microbial biomass pool in chronosequence coal mine spoil. Progressive improvement in clay, hydrological regimes, OC, TN and EP microbial biomass pool and BSR over time was evident from the study. Time dependent increase in integrating quotients was used to monitor the progress of mine spoil genesis. Decline in microbial metabolic quotient over time revealed the progress of mine spoil genesis. Stepwise multiple regression analysis revealed the contribution of physicochemical attributes influencing variability in microbial biomass. The shift in physicochemical properties and microbial biomass correlated well with the extent of land degradation, which can be used as effective biomarkers for monitoring the pace and progress of mine spoil genesis. The fresh coal mine spoil to attain soil features of nearby forest soil through mine spoil genesis shall take approximately 29.15 years. The study paves the way of greater understanding not only in the direction to design appropriate management strategies for ecosystem restoration but also to improve soil quality for sustainable development.