The study was conducted at Enyigba mining area in Abakaliki, Southeastern Nigeria, to evaluate the effect of artisanal mineral mining activities on heavy metals (lead, zinc and cadmium) concentrations and Chemical Properties of soils of Enyigba mining area. Auger Soil Samples (0-20cm) were collected at the four compass directions from zero to 100m and 2500m away from the mine site at 10m intervals. At each sampling interval, three samples were collected randomly, to make three replications three composites were obtained at each interval of the four compass directions. Soil sample from a nearby Agbaja Unuhu community were used as controls. The effect of artisanal mineral mining on Lead, Zinc and Cadmium concentrations in soils of the mineral mining area and soil chemical properties were assessed using complete randomized design. The result showed that Lead, Zinc and Cadmium concentration in soils of the mineral mining area were significantly (p<0.05) higher than that of the unmined soil of Agbaja Unuhu. On average Lead concentration was 819.2% higher in soils of mining area than the unmined soil of Agbaja Unuhu and 204.8% higher than the maximum tolerable limit (100mg/kg) in soil. Zinc concentration in soils of Enyigba mining area was 319.9% higher than the unmined soil of Agbaja Unuhu, however it was still below the maximum tolerable limit of 300mg/kg of soil. Cadmium concentration was 8870% higher in soils of the mining area than the unmined soil of Agbaja Unuhu. The result equally revealed negative and significant correlations between concentrations of lead, zinc and cadmium and critical soil chemical properties such as; pH, Available phosphorous, Total Nitrogen, Organic Matter Content, and Cation Exchange Capacity, which indicate that the concentrations of lead, zinc and cadmium have negative impact on the fertility of the soils of the area.
Keywords: Mining, Lead, Zinc, Cadmium, Soil, Chemical properties.