An analysis of the ground water quality within the vicinity of SMC ZIMPLATS mine Tailings dam

Author

Chantelle T Muzondo

Title

An analysis of the ground water quality within the vicinity of SMC ZIMPLATS mine Tailings dam

Abstract

employment to several people and contributing to the success of economies of many
countries. However, mining activities present a considerable threat on the environment,
through the discharge of pollutants into air, soil and water. Also, tailings dams, which
are earthen walls constructed to contain mining wastewater, can contain toxic
elements that can easily leach into the ground and contaminate groundwater. As such,
the study aimed at evaluating the effects of Selous Metallurgical Complex (SMC)
ZIMPLATS tailings dam on groundwater quality. The study employed an experimental
design where three replicates of groundwater samples were collected from five random
points, making a total of fifteen groundwater samples. Standard methods were then used
to analyse the samples for total coliforms, total dissolved solids (TDS), total hardness,
pH, nitrates, Cd, Fe and Pb. Results showed that all sampling points contained coliforms
ranging from 0.33 to 8.33 CFU/100ml. The TDS in the After mine and Borehole 1
samples were above the WHO permissible limit for drinking water. Total hardness
(1886.4 to 2940.9 mg/L) and nitrates (56.9 to 145.7 mg/L) were above the WHO
permitted limits across all sampling points. Nitrate were significantly different across
sites (p < 0.05). pH values were within the WHO threshold (< 7.5), though Borehole 2
was slightly acidic (pH = 5.1±0.01). The Cd concentrations across all sampling sites
conformed to the WHO standards as they were below 0.003 mg/L, the Spring
(0.27±0.02 mg/L) was the only sampling point to record Fe concentrations within the
WHO threshold, whereas the Pb concentrations were above the WHO limit across all
sampling points ranging from 0.1±0.0 mg/L (Spring) to 0.05±0.04 mg/L (Borehole 1).
The Mine, the After mine and Borehole groundwater samples were not significantly
different (p > 0.05) in Pb concentrations. Based on these findings, it can be
recommended that SMC Zimplats should periodically monitor the groundwater quality
so that it complies with the WHO standards. Also, the tailings should be monitored so
as to reduce groundwater contamination.

Date

June 2024

Publisher

BUSE

Keywords

groundwater, Tallings Dam, Mining, SMC ZIMPLATS,
Vicinity, Zimbabwe.

tailings

water quality

Supervisor

N/A