An open and indiscriminate disposal of coal fly ash causes extensive changes in physicochemical properties of soil and water. Few studies propose that coal fly ash is a potential soil ameliorant that may improve the physical, chemical, biological properties, and nutritional quality of the agricultural soil. However, several recent studies documented that incorporation of higher dosages of coal fly ash into water and soil releases toxic elements consequently creating soil and groundwater pollution leading to major health, environmental, and land use problems. To assess the environmental impact of hazardous coal fly ash on the ecological system, physicochemical and hydrogeochemical analysis of both soil and groundwater are performed. X-ray diffractograms (XRD) of soils from agricultural and landfill sites (n = 8) along with coal fly ash (n = 2) show the presence of characteristic minerals of coal fly ash and also toxic arsenic mineral phases suggesting the strong influence of hazardous coal fly ash on agricultural soil. The hydrogeochemical parameters of groundwater samples (n = 27) are analyzed which show elevated concentrations of most of the major ions corresponding to higher values than maximum permissible levels of recommended drinking water standards by World Health Organization (WHO) and Bureau of Indian Standards (BIS). The water quality indices (WQI) suggests poor to unsuitable water for drinking. Conversely, evaluation of various other hydrochemical indices calculated using elemental concentration of the groundwater samples demarcates contamination of water due to the open dumping of coal fly ash and therefore not desirable for drinking purposes.