Vol.:(0123456789) 1 3 International Journal of Civil Engineering https://doi.org/10.1007/s40999-018-0311-2 RESEARCH PAPER Efects of Landill Leachate on Mechanical Behaviour of Adjacent Soil: a Case Study of Saravan Landill, Rasht, Iran Nader Shariatmadari 1  · Behnam Askari Lasaki 2  · Hasan Eshghinezhad 3  · Pourya Alidoust 3 Received: 24 June 2017 / Revised: 13 January 2018 / Accepted: 30 April 2018 © Iran University of Science and Technology 2018 Abstract Urban waste in most cities of Iran is dumped without proper standards of landill construction. Improper implementation of waste barriers leaks of leachate into the surrounding areas, causing soil contamination and other serious environmental problems. The main goal of this study is to determine the possible efects of leachate on the geotechnical properties of contaminated soils around the dump site and estimating a safe zone for a landill site. In this regard, uniaxial compression, direct shear, consolidation and permeability tests were carried out on several samples to assess the possible efects. SEM tests were also conducted to precisely assess the geotechnical parameters and clarify the possible changes in soil characteristics. Results showed that by increasing leachate concentration, maximum uniaxial and shear stresses decrease, and the volumetric strain increases. This behavior continues by getting closer to the contamination source. A decreasing trend in the cohesion and coeicient of permeability and a relatively low decreasing trend in the internal friction angle () were also observed as the contamination concentration increased. According to the results, a 600 m distance from the contamination source is proposed as a safe zone, in which the soil holds its initial properties. This study provides additional insight into the efects of leachate on the spoil texture of soil. Keywords Municipal solid waste · Leachate · Contaminated soil · Geotechnical properties · Safe zone Abbreviations BOD Biochemical oxygen demand COD Chemical oxygen demand TP Total phosphorus pH Potential hydrogen () Friction angle C Cohesion °C Centigrade k Coeicient of permeability A Cross-sectional area of the sample ΔQ Average of inlow and outlow Δt Interval of time h Average head loss across the permeameter/ specimen L Length of specimen 1 Introduction The increasing rate of urbanization and industrialization around the world and the uncontrolled growth of popula- tion especially in developing countries have led to the ever- increasing generation of municipal solid waste (MSW) [1]. The worldwide limited space for storing the MSW is bound to cause crucial problems in the near future, greatly afect- ing human life. MSW management involves various steps including col- lection, transportation, processing and disposal [2]. Land disposal or landilling, despite being uneconomical in the long term, is the most commonly adopted method in the world. Generally, MSW disposal follows two procedures: * Nader Shariatmadari shariatmadari@iust.ac.ir Behnam Askari Lasaki st151040@stud.uni-stuttgart.de Hasan Eshghinezhad eshghinezhad@civileng.iust.ac.ir Pourya Alidoust p_alidoust@civileng.iust.ac.ir 1 Department of Civil Engineering, Iran University of Science and Technology, Narmak, Teharn 16846-13114, Iran 2 School of Civil Engineering, University of Mohaghegh Ardabili, Ardabil, Iran 3 School of Civil Engineering, Iran University of Science and Technology, Narmak, Teharn 16846-13114, Iran