Paper Title
Comparison Of Environmental External Costs Of Rail Transport And Road Transport (Sample Study Of Tehran � Qom Route)

Abstract
External environmental costs of land transportation are costs imposed on the environment by the users of railroad and road transportation and yet are not compensated by those who impose them. The main goal of this research is quantitative evaluation of external environmental costs in railroad and road transportation sections and to compare the two. This is a field and library research which has calculated the external environmental costs including global warming costs and air pollutions costs based on the statistics of the railroad and vehicle traffic of the Tehran � Qom route for the year 1391 (March 20, 2012 to March 20, 2013). For this aim, in order to calculate the external environmental costs in the subject route, first the present transportation conditions of the route in the railroad and road sections were identified, and after identifying the impacts of the land transportation projects, the usable data for calculating the previously mentioned costs were extracted. Finally, by identification and use of the mathematical models used in similar research, the amount of the external environmental costs, the amount of air pollution, and the global warming for the Tehran � Qom freeway in the year 1391 (March 20, 2012 to March 20, 2013) was estimated at 1000 billion Rials. For the railroad transportation in the Tehran � Qom route, this amount was estimated at 20 billion Rials. The comparison between these costs in the two railroad and road section in the subject route revealed that with regard to the passenger and goods transportation capacity in the railroad transportation section, the development of the railroad transportation can impose significantly less external environment costs. Keywords-Railroad and road transportation, External environmental costs, Air pollution, Global warming