Reduction of fossil fuel use has been one of the worldwide environmental problems for a number of decades and several solutions have been introduced to tackle this issue. This paper presents a framework to systematically collect data, and then to develop a quantitative method for optimization of the fuel use of the hauling fleet. For this purpose, a large dam construction project was selected as a case study. The hauling fleet included dump trucks with capacities of 35 and 45 tons. The collected data were analyzed by the linear multivariate regression method and then linear programming was used to optimize the fuel use of the dump truck fleet in earthmoving jobsites.