‘Extraction for Thar coal not to impact drinking water’

KARACHI: Sindh Engro Coal Mining Company (SECMC) said the mining project of Thar Coal Block II will pump out only 0.02 percent of underground water, which will not impact the drinking water sources of the area.

Waqas Abdul Aziz, hydrogeology manager at SECMC in a statement on Friday said the water being extracted comes from the 2nd and the 3rd aquifers which are at 120 meters and 180 meters, below the surface, and are not connected to the top aquifer at 55 meters being used by the locals for drinking purposes.

“Considering the scale of mining operations and potential of underground water in the region of Thar, only 0.02 percent of underground water will be pumped out per year from the estimated available water in the region of Thar,” he said.

Citing the reasons for dewatering the mine, Waqas said for smooth mining operations, depressurisation of underground water was necessary to reach the depth of coal, which was available at 150 meters.

“We need to understand this fact that for mining operations our main target is to depressurise coal seam roof and floor aquifer not to dewater them completely,” he said.

The manager explained that Thar coal region has mainly three underground aquifers available at 55, 120 and 180 meters, respectively.

The first aquifer is the primary source of drinking water for the people of Thar, which is not being dewatered during the mining operations, Aziz said, and added that the depressurising water ranges salinity from 4,000 to 5,000 parts per million.

“Total groundwater potential for the area of coal deposits 9,100 square kilometre is approximately 67 to 73 billion meters,” the SECMC official said.

He was of the view that mining operations at Block II were continuously depressurising second and third aquifer only to reach target coal depth of 180 meters through the network of 27 dewatering wells installed in the periphery of mine in an area of around 1.5 square kilometres in Block II.