Practical solutions to soil pollution by the petroleum industry are still to be fully realised. With new, unresolved and recurring cases, remediation options that are readily available, cost effective and environmentally friendly are required. Analytical methods for quick and easy monitoring are also crucial. To find appropriate solutions to petroleum-contaminated soils particularly for the Niger Delta, Nigeria; options, which satisfy the above principles, were investigated. Thus, the aims of this research were to identify readily available and sustainable techniques for remediation of petroleum-contaminated soils; evaluate ways to overcoming associated limitations, thereby enhancing these techniques; and investigate for readily available methods of monitoring the petroleum-contaminated and remediated soils. After a systematic and critical literature review, phyto- and myco-remediation were identified as viable options for this research, their limitations were evaluated. The actual study involved sampling of petroleum contaminated soils, treatment with phyto- and myco-remediation agents and investigation of methods for analysis and monitoring of the soils. Agents used for the remediation (evaluated in terms of reduction in Total Petroleum Hydrocarbons-TPHs in the soil samples) were: 3 species of sunflowers (Helianthus annus-pacino gold, Helianthus sunsation & Helianthus annus-sunny dwarf), the fern-Dryopteris affinis, fermented palm wine (from 2 species of palm trees -Elaeis guineensis & Raffia africana), and oyster mushroom (Pleurotus ostreatus). Supplementing the agents with Tween 80 and the use of alternative substrates and methods for application of P. ostreatus enabled the investigation of possible enhancement of their remediation efficiency. The investigation revealed up to 525 g of TPHs per Kg dry weight of soils. The remediation treatments produced as much as 69% reduction in TPHs by the sunflower species, 70% by fermented palm wine, 74% by D. affinis and 85% by P. ostreatus; with up to 100% enhancement on the addition of Tween-80. It was also found that substrates type and method of application has a significant effect on the remediation efficiency of P. ostreatus. The study further revealed that available nitrate, electrical conductivity, standardised crude oil and the biomarkers dodecane and benzene-1,3-bis(1,1-dimethylethyl) can be used to broadly monitor the concentration of TPHs and remediation progress in soils. This research thus demonstrated that, phyto-and myco-remediation can provide readily available and sustainable techniques for remediation of TPHs in soils. Further studies are required to evaluate the application of these techniques for individual petroleum contaminant components such as the polycyclic aromatic hydrocarbon compounds and Asphaltenes
