IJE TRANSACTIONS A: Basics Vol. 35, No. 01, (January 2022) 201-212 Please cite this article as: Sumalatha J., M. Kumar C. L., P. Sunagar, Shwetha K. G., E. Noroozinejad Farsangi, Studies on Contaminated Mine Soil and Its Remediation Using Soil Washing Technique: A Case Study on Soil at Kolar Gold Fields, International Journal of Engineering, Transactions A: Basics Vol. 35, No. 01, (2022) 201-212 International Journal of Engineering Journal Homepage: www.ije.ir Studies on Contaminated Mine Soil and Its Remediation using Soil Washing Technique: A Case Study on Soil at Kolar Gold Fields Sumalatha J. a , M. Kumar C. L. b , P. Sunagar a , Shwetha K. G. b , E. Noroozinejad Farsangi* c a Department of Civil Engineering, M S Ramaiah Institute of Technology, Bangalore, India b Department of Civil Engineering, Nitte Meenakshi Institute of Technology, Yelahanka, Bengaluru, Karnataka, India c Faculty of Civil and Surveying Engineering, Graduate University of Advanced Technology, Kerman, Iran PAPER INFO Paper history: Received 23 September 2021 Received in revised form 07 November 2021 Accepted 09 November 2021 Keywords: Mine Soil Contamination Bearing Capacity Settlement Kolar Gold Fields ABSTRACT Uncontrolled mining and the tailings produced can cause significant environmental impacts such as water, air, and soil pollution. In the present study, a contaminated soil of gold mines located in the Karnataka state of India was studied to know the geotechnical behavior of this soil as a foundation material and to suggest a suitable soil remediation technique to avoid contamination of surrounding water bodies. The in-situ dry unit weight of soil at the selected locations varied from 15.71 to 18.75 kN/m 3 . The effective shear strength parameters determined from Triaxial test results were in the range of 4.8 – 8.2 kN/m 2 and 19.4 0 – 29.8 0 , respectively, for the cohesion and angle of internal friction. The soil samples were analyzed for bearing capacity and settlement using GEO5 software tool, and the economical dimensions of the footings were estimated. It was observed that the soil has sufficient bearing capacity, and the settlements are within the allowable range. The chemical analysis of the soil samples showed that there are considerable amounts of heavy metals present in the mine soil. Though the strength of the soil is good, the contaminants in the soil may cause groundwater contamination and damages to the footings. Hence, the soil washing technique as a remediation technique was also studied through column leaching tests using different leaching solutions and found that diluted hydrochloric acid (HCl) with Ethylenediamine-tetraacetic acid (EDTA) can effectively remove the heavy metals from the soil. doi: 10.5829/ije.2022.35.01a.19 1. INTRODUCTION 1 In most of the mining areas around the world, the presence of poisonous metals was observed in soil and water which caused environmental damage. The widespread metal pollution happened due to mining and smelting activities at the site may lead to multiple environmental problems [1-3]. The waste products from the mining process which are called tailings primarily consist of sand, silt, and clay sized materials with chemicals and process water. The mineralized rock from the mines is processed and reduced in size to recover the economic mineral. A significant volume of tailings produced from mining and processing is generally left as permanent features of the landscape after the mining *Corresponding Author Institutional Email: noroozinejad@kgut.ac.ir (E. Noroozinejad Farsangi) ceases [4]. These tailings hold minerals such as chlorite, mica, quartz, etc. and also contain micronutrients [5-6]. The ecological restoration of dumps can be made using these mill tailings containing the nutrients and the effective method of stabilization of mine wastes is by growing a vegetation cover over the dumps [7-8]. The long-term stability, aesthetic view and low maintenance are possible by using native species for the vegetation cover. To assess the suitability of different species of plants, the tailings can be mixed with the soil in different proportions and their effectiveness can be studied [7]. Apart from the metal extraction, the mining activities are also common to extract thermal water which will be used for power generation and medical spa treatments [9].