Abstract <p>This paper presents the development of an integrated approach to mitigating the consequences of accidental spills of fuel oil and other petroleum products in aquatic and coastal environments. The proposed concept comprises two complementary components: a mobile oil spill containment system, already implemented at the industrial level, and a mobile plasma-chemical unit designed for on-site processing of collected waste directly within the emergency area. Particular attention is focused on the theoretical assessment of the plasma-chemical unit parameters. Due to the complex fractional composition of fuel oil, its structural formula cannot be uniquely defined; therefore, an approximation based on the elemental carbon-to-hydrogen ratio was employed. The results show that the obtained ratio (H/C ≈ 1.9) is close to that of polyethylene, which enables the application of similar methodological approaches and previously validated mathematical models. Based on the C–H model, stoichiometric and energy assessments were performed, potential target products (calcium carbide and hydrogen) were identified, and the key parameters of the discharge active zone were determined. The study is preliminary in nature and provides a foundation for further experimental investigations and detailed engineering design of a mobile plasma-chemical processing unit.</p>