Determination of Production Cap of Iron Ore Mining in Goa Region based on Infrastructural and Environmental Carrying Capacity

摘要

Iron ore mining is a major economic activity in Goa (India) contributing to about 20.4% of Gross Domestic Product (GDP) of the State's economy. Increased iron ore production has resulted in substantial stress on the existing ore transportation routes. It is therefore prudent to develop a planning tool to optimize the production. The paper aims to estimate the optimum production capacity of the region with due consideration of the carrying capacity of roads and environmental pollution load. Eighteen (18) major ore transportation routes have been identified across the Goa mining region. The impact of ore transportation activity on the local air quality has been evaluated using dispersion modelling through AERMODview8.1. Emission inventory for PM_(10) and PM_(2.5) has been prepared as per AP42 guidelines for the existing scenario. Along with this meteorological and terrain data for the year 2011 and 2012 have been processed as input for the model. In order to validate the model actual monitoring has been carried out at nine (9) monitoring locations sited along the ore transportation routes. These stations are mostly located at the junctions of the ore transportation routes. The coefficient of determination was found to be high (0.69) for PM_(10) and moderate (0.57) for PM_(2.5) indicating high and moderate correlation, respectively between observed and predicted concentration values from the model. Thus, use of the model with respect to the proposed future scenario is justified for predicting concentration levels. Consequently, to develop an alternative ' scenario optimum carrying capacity of these ore transportation routes has been evaluated based on the guidelines prescribed by Indian Road Congress (IRC), incorporating the applicable restrictions. Environmental load under the alternative scenario has been forecasted using dispersion modelling through AERM0Dview8.1. The results of modelling clearly reveals that under the proposed scenario the pollution levels on the ore transportation routes is significantly reduced. Subsequently, AQI was also found to be under a lower health risk regime. Accordingly, factors contributing to high pollution load due to ore transportation has been identified and various alternatives for appropriate air quality management have been proposed.