The way of sampling and preservation for Total Petroleum Hydrocarbon (TPH) are importance step. For sampling, we must take sample that representative environmental sample. Sample for TPH has heterogenic properties, wide range volatility, solubility, biodegradation and adsorption potential of individual constituents. Besides sampling, the next step is to preserve the sample. That is importance too especially when the sample is not directly analyzed. Many reasons why the sample could not be immediately reached the laboratory. One of the reasons is a far sampling location. The procedure to preservation sample that recommended by U.S EPA guidelines is included in Table 1.
Total Petroleum Hydrocarbon Criteria Working Groups Series. Volume 1. Analysis of Petroleum Hydrocarbons in Environmental Media. March 1998. Amherst Scientific Publishers.