مدل جدید برای ارزیابی اثرات زیست محیطی پروژه های تونل سازی  New Model for Environmental Impact Assessment of Tunneling Projects

1. Introduction The concept of Environmental Impact Assessment (EIA) refers to the examination, analysis and assessment of planned activities with a view to ensuring their environmental soundness and sustainable development. It is said to be a valuable means of promoting the integration of environmental and natural resource issues into planning and program implementation [1]. Since its introduction in the United States in the late 1960s, EIA has been adopted and implemented by many developed and developing countries [2]-[13]. Numerous EIA methodologies have been developed such as interaction matrices, networks, weighting-scaling (or -ranking or -rating) checklists [14], multicriteria/multiattribute decision analysis (MCDA/MADA) [15]-[30], input-output analysis [30], life cycle assessment (LCA) [32]-[34], AHP or fuzzy AHP [35]-[37], fuzzy sets approaches [38]-[41], Rapid Impact Assessment Matrix (RIAM) [41]- [44], and data envelopment analysis (DEA) [46]. The purpose of incorporating EIA approaches has been described as subjecting a proposed action to an examination of what the possible environmental impacts of that action would be and to find ways to mitigate any negative long-term impacts [47]. Therefore, the main aims of the environmental assessment could be summarized as follows [48]: Prevention of the destructive effects, resulting from mining activities. 5. Discussion Compare all the above cases with standard values obtained for each environmental component indicates that effects of urban utility tunnel construction in congested city Tehran on area landscape, area usage, soil of the area and quietness exceeded from standard values. The impact on air quality, groundwater and the surface is slightly higher than standard, too. In operation phase this tunnel has no significant impact on the environmental components while social issues show an exceedance from the standard amount (Figure 7).