It is proven that the financial benefits of using the proposed new tailings materials in terms of environmental sustainability are much higher when compared to normal materials. The research has been conducted to investigate the possible environmental problems of using iron ore mine tailings in civil engineering projects (road construction materials). Therefore, two main iron ore mine tailings of Gol-e-Gohar complex produced in magnetite and hematite plants were evaluated in terms of leaching heavy elements after application as road materials. To address the potential application of tailings as road materials, the main characteristics of tailings such as elemental analysis, pollution indicators, and engineering properties after stabilization by Portland cement were measured. The leaching of dangerous elements in a natural and stabilized state of compacted tailings at different times and pHs were assessed. The total amount of elements by ICP analysis showed that the Mn, Fe, Zn, Cd, Ni, and Cu are more abundant in the two tailings and their leaching must be tested. The general results showed that leaching with different leakage times and solutions at different pH have no effect on the release of elements through tailings, so their efficiency as road materials from an environmental point of view is acceptable providing meet the engineering standards as materials. In addition to leaching experiments, contamination, enrichment, and geo-accumulation indices also confirmed leaching results.