Tanneries impact on groundwater quality: a case study of Kasur city in Pakistan

Leather industry is the second largest export-earning sector of Pakistan. However, because of poor waste management, this industry has been continuously polluting the environment. In this paper, the impact of tanneries on the groundwater quality of Kasur city (i.e., the second largest leather producing city) is examined. The study is conducted in the following three phases: (I) water samples collection, (II) determination of physio-chemical properties, and (III) application of data mining techniques. In phase I, groundwater samples were collected from various sources such as hand pumps, motor pumps, and tube wells. In phase II, several physio-chemical properties such as (i) total dissolved solids (TDS), (ii) pH, (iii) turbidity, (iv) electrical conductivity (EC), (v) total hardness (TH), (vi) total alkalinity (TA), (vii) nitrates, (viii) chromium, (ix) fluoride, and (x) chloride were estimated. The estimated values of all these foregoing parameters are then compared with the Punjab Environmental Quality Standards for Drinking Water (PEQSDW). In phase III, principle component analysis and cluster analysis of the estimated parameters were performed to elucidate the relation between various parameters and to highlight the highly vulnerable sites, respectively. The results exhibit that most of the sampling collections sites are at the threshold of losing quality water. Moreover, it is also found that Mangal Mandi carries the worst groundwater quality among all sampling locations. Overall, it is concluded that serious attention is due from the water and wastewater authorities to further investigate and monitor the groundwater quality of Kasur before the country strikes with another pandemic after COVID-19.