Comparative Life Cycle Assessment of Road and Multimodal Transportation Options - A Case Study of Copperwood Project

Abstract

Freight transportation of goods and commodities is a necessity and often accounts for a significant portion of the overall investment in the industrial development, especially in natural resource industry. The economic costs of developing infrastructure have long been factored into the project costs, but environmental or social impacts have received less attention. In addition, alternative transportation modes are rarely compared from both economic and environmental perspectives. This paper assesses different transportation options to transport ore between a planned mine and a processing plant. The transportation options include truck only option and two multimodal (truck-rail) options. Environmental impact assessment of all three options is done by a process called Life Cycle Assessment (LCA) using standard LCA tools. The output of the LCA will be the overall Global Warming Potential (GWP) in terms of kilogram equivalents of CO₂ (kg CO₂eq). The analysis is performed for different time periods of mining operations and the emissions generated by each transportation option are compared on the basis of one ton (US ton) of ore transported. The impacts of construction, operations and maintenance for each option are also discussed. The results suggest that operations stage of the project account for majority of the emissions for all three options and they remain fairly static for each mine life. There are large differences in the actual emission quantities from truck only vs. multimodal options and it is recognized that the percentage of construction emissions depends on the life of mine. Overall, the multimodal options showed significantly reduced emissions in the operations stage, resulting in lower overall project emissions for those alternatives.