The proposed diamond mine in the Buxwaha protected forest region in Chhatarpur district of Madhya Pradesh may have a greater ecological impact on the region than projected so far.
The project threatens to further deplete the already scarce water reserve of the drought-prone Bundelkhand region to excavate about five million tonnes of diamond-bearing kimberlite ore per annum.
Diamond mining is a water-intensive process. The water requirement for the Bunder mine and ore processing plant is about 16,050 cubic metres per day (5.9 million cubic meters in a year), according to the pre-feasibility report of the project. The project is estimated go on for 14 years.
The Bunder mining project was awarded to Essel Mining & Industries Limited in 2019. The company, in its application for environmental clearance, stated that to meet water requirements and protect the mine from inundation, a seasonal nullah (stream) will be converted into a dam.
A seasonal nullah, however, will not be enough to meet the water requirement of the project, said the tribal communities and locals of Chattarpur. They fear the company may end up using groundwater for the purpose.
This is likely to exacerbate the water scarcity problem in the region, according to experts.
PG Najpande from Jabalpur, a local activist, filed a public interest litigation in National Green Tribunal (NGT) to stop the project. He said:
Do Bundelkhand’s streams even have water? This is a mere facade. The company says it will make a dam using the stream water. But when the monsoon ends the stream also goes dry. It is not perennial.
The Chhatarpur was categorised as a semi-critical region by the Central Ground Water Authority in 2017.
In 2020, the district recorded a rain deficit of 24 per cent, according to the Indian Meteorological Department. Low rainfall has been the trend in the district as well as in the Bundelkhand region: There was a deficit of 10 per cent in 2018; 27 per cent in 2019 and 24 per cent in 2020.
Essel is yet to receive approval from the state’s water resource ministry.
Around 200,000 trees also will be felled for the excavation. Environmentalists and local communities have been protesting against the project for over a month.
Waste from tailing ponds and water-pollution
Two major kinds of waste are generated during the excavation of any ore. One, overburden (OB) waste which lies over the ore, such as rocks and soil. The other is tailings or the remains of the mineral after the economically valuable components have been extracted from the finely milled ore.
Under the Bunder project, five metric tonnes of kimberlite ore will be excavated per annum. Its mining would generate about 3.70 metric tonnes of soil waste, 16.34 metric tonnes of OB waste and 5 metric tonnes of tailing waste annually.
A large part of the auctioned forest land will be used for dumping waste. Over 86 hectares of land will be required to dump OB waste, 12 hectares for soil waste and over 50 hectares for tailings.
Soil and OB wastes are not contaminated and thus are easy to dispose of. But tailings are disposed of in dams or ponds usually built around the mining site. The tailing ponds contain process-affected water, dissolved metals and various toxic ore processing reagents that can seep into the ground.
“The problem will be to identify the location for the tailing ponds and how to manage them after the diamond is extracted,” said an official from the Geological Survey of India on condition of anonymity.
There have been several reports of contaminated waste leaching into the groundwater and the tailing ponds overflowing in the monsoon. In April 2011, leakage from the red mud pond containing bauxite residue of the aluminium refinery of Vedanta Ltd in Odisha entered River Vamsadhara and caused enormous damage to the environment.
The Geological Survey of India official added:
Diamond extraction is not mechanical extraction and requires a lot of chemicals besides water. These chemicals do leak out. If it’s soluble in the water, then even if we treat the water it still remains there. The long-term impact of it is seen on animals, humans and the environment.
Apart from spatial requirements for storage, tailings also require long-term management and rehabilitation. Soil and groundwater degradation of the surrounding areas is a common impact of tailing ponds. Since the toxic waste is supposed to be there for a long time, its impact too will be long-term.