Slime Dump Stabilization of Iron Mine by Use of Jute Geotextile—A Case Study of Noamundi Iron Mine

Abstract

Extraction of iron ore through open cast mining technique is most common and popular practice in India. The method is also very cost effective and more profitable as entire mineral is being excavated from the mine. But it creates major environmental hazards by generation of huge quantity of mine waste and its dumping on nearby land. Mine waste is collected and stored as dump which occupies a huge space. The dumps are categorized depending on its use like, waste dump and subgrade dump. However, to produce best steel grade material, the iron ore is processed and cleaned through wet technology. The rejected waste known as slime is collected and stored in pond. After evacuation of water/moisture from the slime it is stored as slime dump for future use. In most of the cases the height of dumps reaches beyond its limit and tends to collapse. By this way in most of the cases the dumps become overburden (OB Dump) and destabilizes. Eventually, due to presence of very fine quality of material high rate of erosion takes place in slime dumps owing to precipitation and wind which further affect the stability of dump. The situation gradually becomes worst causing serious environmental pollution and degradation of nearby land. Mining can become more environmentally sustainable by developing and integrating best environmental practices in mining operations. These practices include preventing soil, air, and water pollution, adoption of zero liquid discharge, reduced energy consumption, adequate waste utilization, social awareness, and conducting successful reclamation activities. In order to stabilize the OB Dumps appropriate measures need to be taken for rehabilitation and ensure erosion control of slope with suitable material along with adopting bioengineering technique. Jute geotextile (JGT) an eco-friendly, cost effective, material developed by Jute Geotextile Cell (JGT) of National Jute Board, Ministry of Textiles, Govt. of India is being widely used all over the world in various forms for mitigating such soil related problems. Performance of JGT has been reported to be much superior technically to other available materials meant for erosion control works apart from its environmental advantages. It possesses high tensile strength, biodegradable characteristics and is commonly used for erosion control, road construction, hill slope management, etc. The use of JGT on trial basis in Noamundi Iron Mine of TATA steel Ltd in slime dump management was undertaken for the 1st time. The results observed within a period of 3 months after application of JGT was highly encouraging. Vegetation was grown through the openings of JGT and the slime dump was stabilized. The features of the site, methodology adopted along with properties of JGT and its effect are explained in this paper.