Review A review of electrokinetically enhanced bioremediation technologies for PHs Anish Saini 1,2 , Dawit Nega Bekele 1,2 , Sreenivasulu Chadalavada 1,2 , Cheng Fang 1,2 , Ravi Naidu 1,2, ⁎ 1. Global Centre for Environmental Remediation, University of Newcastle, Callaghan, Newcastle 2308, NSW, Australia 2. Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, Newcastle 2308, NSW, Australia ARTICLE INFO ABSTRACT Article history: Received 10 May 2019 Revised 13 August 2019 Accepted 13 August 2019 Available online 21 August 2019 Since the early 1980’s there have been several different strategies designed and applied to the remediation of subsurface environment including physical, chemical and biological approaches. They have had varying degrees of success in remediating contaminants from subsurface soils and groundwater. The objective of this review is to examine the range of technologies for the remediation of contaminants, particularly petroleum hydrocarbons, in subsurfaces with a specific focus on bioremediation and electrokinetic remediation. Further, this review examines the efficiency of remediation carried out by combining bioremediation and electrokinetic remediation. Surfactants, which are slowly becoming the selected chemicals for mobilizing contaminants, are also considered in this review. The current knowledge gaps of these technologies and techniques identified which could lead to development of more efficient ways of utilizing these technologies or development of a completely new technology. © 2019 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. Keywords: Subsurface contamination Remediation Petroleum hydrocarbons (PH) Electrokinetics Bioremediation Contents Introduction ............................................................ 32 1. Petroleum hydrocarbons (PH) contamination ........................................ 32 1.1. Fate of PH contaminants in the subsurface ...................................... 33 2. Bioremediation of PH ..................................................... 33 2.1. Bioremediation techniques .............................................. 34 3. Electrokinetics ......................................................... 34 3.1. Electrokinetic remediation process .......................................... 34 3.2. Electrokinetic remediation technologies ....................................... 35 3.2.1. Conventional anode–cathode ......................................... 35 JOURNAL OF ENVIRONMENTAL SCIENCES 88 (2020) 31 – 45 ⁎ Corresponding author. E-mail: ravi.naidu@newcastle.edu.au (Ravi Naidu). https://doi.org/10.1016/j.jes.2019.08.010 1001-0742 © 2019 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. Available online at www.sciencedirect.com ScienceDirect www.elsevier.com/locate/jes