Assessment of Groundwater Quality around Abandoned Quarry Ponds near Lower Benue Trough, Nigeria

A field study was conducted on the Assessment of Ground Water Quality Around Abandoned Quarry Ponds near Lower Benue Trough, Nigeria and to establish how the Ponds were influenced by past quarrying activities. Water samples were collected from the four abandoned quarry ponds measured fifty meters (50 m) (165 ft) deep. These were labeled ABP1, ABP2, ABP3, ABP4, while the wells were labeled HDW (hand dug wells) measured eighty meters (80 m) (264 ft) deep and BH (borehole), measured two hundred eighty meters (280 m) (924 ft). In-situ measurements were done with HORIBA U-10 Water Quality Checker to determine pH, temperature, total dissolved solids, turbidity, conductivity, and salinity. Descriptive statistics, Pearson correlation (r) and test of homogeneity (ANOVA) were used to analyse data. There were no wide variations in the levels of the physicochemical parameters of water samples from the abandoned quarry ponds and wells. pH levels ranged between 6.800 and 8.000 (7.200±0.225), temperature ranged between 29.000 and 29.400 (29.067±0.0667) °C, turbidity ranged between 5.00 and 20.00 (10.83±2.71) NTU, total dissolved solids (TDS) ranged between 500 and 1020 (720±103) mg/L, total suspended solids (TSS) ranged between 50 and 800 (525±106) mg/L, Salinity ranged between 5.00 and 15.00 (10.00±1.83) 0/00, conductivity ranged between 50.0 and 500.0 (183.7±69.1) µS∕cm, CaCO3 ranged between30.0 and 500.0 (355.0±92.2) mg/L, Nitrate ranged between8.00 and 25.00 (13.83±2.52) mg/L, Sulfate150.0 and 280.0 (215.0±18.4) mg/L while Sodium 205.0 and 300.0 (255.8±15.5) mg/L. There was significant variation in concentrations of the physiochemical parameters measured [F (19.27) > F crit (2.37)] at P< 0.05 and sodium, conductivity, Sulfate and Calcium Carbonate were the most responsible for the observed inequality. Nitrate correlated positively with turbidity(r=0.942), and sulfate correlated positively with total dissolved solids (r=0.942) while turbidity correlated positively with total dissolved solids, (r=0.930) and (r=0.964) at P<0.01. Study findings include increased levels of the physiochemical parameters in the hand dug wells which are therefore a grave danger to consumers. The near surface water table and rock over-breaking due to uncontrolled blasting are enhancing pond water and groundwater interaction, and the resultant groundwater pollution in the study areas. Therefore, the quarry operators must reclaim the pits before departing or provide for the reclamation.