A composition and method for a non-emulsion crude oil simulant containing biodegradable oil, and a terpene is disclosed and described. Biodegradable oils such as canola oil, cottonseed oil, and soybean oil can be particularly beneficial for use in connection with these oil simulants. Terpenes such as d-limonene can be included to provide oil simulant compositions which exhibit good oil simulant properties. Additives such as photochromic dyes, food dyes, food-grade antioxidants, microorganisms, and nutrients can also be used. These non-emulsion based oil simulants can be readily tailored and adjusted to approximate relevant properties of a specific target fluid for use in assessing oil spill response, containment, clean-up of equipment, percolation, and/or spill behavior.