2. In this regard, Matrix-Based Risk Assessment Approach is also applicable based on design of a matrix which illustrates every 100m of On this basis,combination of indexing system beside analytical hierarchy process was used. Passing through zanjan desert,a terminal part of this line travels from salty lands of western Azerbaijan Province. The objective of construction such a pipe line is to boost the AabparขZanjan gas line and especially hinder of pressure drop in cold seasons. Although the diameter of the total pipe line has been measured as 24 inches, the width differs significantly close to residential regions, protected area surrounded the cities, stations and intersections of asphalt roads and railways as well, in order to reach to standard immunity ratio. Applied pipe comprised of steel and of API-5LX 60 type was isolated with 3-layers polyethylene.