A method or process of treating a contaminated fluid (10) having at least one contaminant having a property selected from the group consisting of being volatile, hazardous, tacky and a combination thereof is provided. The method comprises contacting the contaminated fluid with an effective amount of an agent (12) selected from oxidizing agents, free radical producing agents and a combination thereof for an effective amount of time to convert a substantial amount of the at least one contaminant to at least one corresponding modified contaminant having a property selected from the group consisting of being non-volatile, less volatile than the converted contaminant non-hazardous, less hazardous than the converted contaminant, non-tacky and a combination thereof; and generating a treated fluid (14) having a level of the at least one contaminant and of the at least one corresponding modified contaminant to allow the treated fluid to at least meet requirements for release, reuse or further treatment.