Petroleum hydrocarbons are the biggest group of chemicals as determined by quantity and quality of environment pollution in the world. Alone gasoline stations are a huge problem by spilling pollutants in the environment: air, ground water and soil. Since petroleum hydrocarbons contain also some toxic volatiles (BTEX), solvents (hexane, etc.) analysis of these compounds is very important: analytical procedures are required at the field to minimise laboratory samples and to enhance cleanup. Also right sample preparation, transportation and laboratory analysis are crucial. In this study all these aspects were determined and methods were developed to keep the information from the field to the laboratory intact.