Reducing Environmental Hazards of Blasting Using Electronic Detonators in a Large Opencast Coal Project - A Case Study

Abstract

The core objectives of Indian Ministry of Coal in its vision statement is securing the availability of coal to meet the demand of different sector of economy in an eco-friendly and sustainable manner. Coal India produced 567.37 million tonnes of raw coal in 2017-18 out of which contribution from opencast mines was 536.82 million tonnes (i.e. 95%). Deep hole blasting for high capacity excavators like draglines, 20 cum shovels becomes imperative for achieving high production targets. Thus, environmental hazards associated with deep hole blasting is also bound to happen. One of the serious problems faced by deep hole blasting is that of ground vibrations. In Khadia opencast coal project the power plants, Rihand dam is in vicinity and local population in and around mines, controlling ground vibration was of paramount importance for the project. Hence, it became a challenge for reduction of environmental hazards involving deep hole blast for dragline; shovels using electronic detonators, for providing precision delay and maximizing the vibration of explosive energy. The blast design parameters using electronic detonator for various blasts of dragline benches were tried to know the resultant profile of ground vibrations near human settlement of Khadia project. This has also resulted in improvement of powder factor (volume of rock fragmentation per kg of explosive used). This paper deals with, as to how the environmental impacts due to ground vibrations of rock blasting, are reduced resulting in no complaints for dwellers and any authorities in and around Khadia project.