According to the proposed aims (objectives) and contents in this project, we summarize our accomplishments as follows. The established Excel and Endnotes databases have updated which collected 258 research articles in total corresponding to the oil spill identification, and also created a keyword classification index. These literatures were reviewed to include 1. dibenzothiophenes fingerprinting identification technology for age-dating study; 2. the application of statistics analysis for the classification of the principal component analysis (PCA) of source oils; 3. gasoline spill contaminated identification technology. In overall, based on the results accumulated in this project, we have achieved our goals to renew the operation protocols of the chemical fingerprinting technology for the oil spill identification. Moreover, an operation procedure guideline for the identification of the diesel spill pollution of gas stations has also been drafted. 40 commercialized diesel samples collected from the gas stations of both CPC Co., Taiwan, and Formosa Petroleum Corporation, were acquired for GC/MS analysis and subsequent data process. The information has been updated for the chemical fingerprint database of the commercialized diesels. To gather 307 samples collected since the first stage diesel forensics research project until now, we have further carried out the study of their principal component analysis-diagnostics ratios (PCA-DRs) and been verifying the technology that we have built since last project which is indeed valid for source identification of the commercialized diesel oils. Proposals for quality control of soil collection and identification and characterization of soil samples polluted by diesel spill collected from 15 identified sites have been drafted and illustrated. 11 gas station sites with diesel spill were carried out the soil sample collection and 103 diesel spill soil samples were obtained from these sites. Additional 47 polluted soil samples from 9 diesel spill contaminated sites were also provided by private sector and executors of oil tank survey project. Among them, four polluted sites were actually repeated. Hence, there were 150 samples being obtained from 16 contaminated sites in total. Pretreatment of 106 soil samples from 16 diesel spill contaminated sites were carried out and subsequently acquired by GC/MS analysis and data process. All the PCA-DRs cluster analyses for the classification of the diesel oils from the polluted sites were verified for their applications. We have also provided 20 and 25 diagnostic ratio groups, respectively, for the ones without and with the gasoline interferences. The protocols for source oil identification from the diesel spill sites and their operation procedures were suggested. The source investigation and identification of diesel spills from gasoline stations have been completely established. The relative amount of dibenzothiophene derivatives to C4-naphthalenes in the soil extract can be applied for the age-dating preliminary estimate of diesel spill. This project completes the application case analysis of 16 contaminated sites and summarizes the current reference procedures that can be followed. Three technical seminars for the identification and characterization of the oil spill have been held at EPA. The project leader participated in the International Network of Environmental Forensics (INEF) conference held in Beijing in July 2017, and presented the project performed result. One book chapter was published in English and 4 poster presentations were performed in domestic conferences.

GC/MS, Measuring Technologies, Principal Component Analysis, Diagnostic ratio, Chemical fingerprint chromatogram, Biomarker, Diesel, Environmental forensics