Apply Environmental Forensic Techniques to Establish Commercial Diesel Fingerprint Investigation Pla
The final report is divided into the following parts: In this project, fourteen papers relevant to spilled-oil identification are collected and added into the previously established Excel Database which now amounts to 245 documents. Besides diesel spilled-oil identification papers ,we reviewed about gasoline identification techniques, weathering processes of biodiesel ,and different oil spill identification papers. In addition to documents analysis, the project scrutinizes 149 bilingual professional terms which were collected from those used by previous project, website and mainland China. The project also provides Environmental Protection Administration (EPA) with a draft of standard operating procedure (SOP) and execution framework of spilled-oil identification techniques for contaminated soil and underground water. We collected 126 diesel samples in different gas stations around Taiwan supplied by either CPC Corporation, Taiwan (CPC) or Formosa Petroleum Corporation (FPC). A Gas Chromatography/Mass Spectrometry (GC/MS) analysis of these samples was carried out. The data processing of at least five groups of chemical fingerprint distributions and diagnostic ratios were performed for all samples. In the meantime, we established a chemical fingerprints database for future reference. Based on the analysis result, we screened out 41 diagnostic ratios and among them there are 29 with the value of Diagnostic Power (DP) bigger than five. We also conducted the cluster analysis for 126 samples through Principal Component Analysis (PCA). The results of the study can discern the difference of the diesel oil source between CPC and FPC. With the analysis results of 267 gas station diesel samples which includes some diesel samples used in this project and others (B2 diesel) in previous project, we prove the practicability and feasibility of the identification techniques for diesel oil source. We completed the GC/MS analysis of 72 diesel samples including hydrogen desulfurization refined products and those before leaving factory in both CPC and FPC Refinery. Among these samples a data processing of at least five groups of chemical fingerprint distributions and diagnostic ratios was carried out. A comprehensive analysis of the character of marketing diesel, hydrogen desulfurization diesel and those before leaving factory was executed We used diesels from CPC and FPC to produce three different mixed diesels with the ratios of 75:25, 50:50 and 25:75. We performed eighty-one GC/MS analysis and conducted the data processing of at least five groups of chemical fingerprint distributions and diagnostic ratios. The study conducted correlation of chemical fingerprint distributions, diagnostic ratios calculation, PCA of above-mentioned eighty-one mixed diesel samples. We also carried out simulation calculation of diagnostic ratios of above-mentioned eighty-one mixed oil samples through the diagnostic ratios of pure diesel samples and performed PCA cluster analysis of simulation calculation of diagnostic ratios. The correlation between PCA cluster analysis of real mixed oil samples and that of simulated mixed oil samples indicates that they are characteristic of similar cluster distribution. This project completed pretreatment and GC/MS analysis of 33 contaminated soil samples collected from six diesel contaminated sites and carried out the data processing of at least five groups of chemical fingerprint distributions and diagnostic ratios. Based on the study of this and previous projects, we screened out the 41 diagnostic ratios of forensic marketing diesel sources and among them there are 21 diagnostic ratios with the value of DP bigger than five. We also deleted the diagnostic ratios that were interfered by mixed gasoline contamination, dissolution and biodegradation. Furthermore, we screened out 36 diagnostic ratios which are suitable for forensic identification and among them there are 18 with value of DP bigger than five. The PCA of contaminated soil samples from four verified spilled-diesel sites indicates that the technology of diesel source identification is suitable for identifying the spilled-diesel contamination which was influenced by disturbance of mixed gasoline contamination, dissolution, and light to moderate biodegradation. As the four above-mentioned contaminated sites could not represent all, screening out more sites with various contamination factors is needed to verify its suitability and improve it for future use. This project completed the transfers of forensic identification technologies three times separately after preliminary report, mid-term report and before final report. The results of this and previous projects have been presented in 2015 International Network of Environmental Forensics (INEF) held in Canada during Aug 3-6, 2015.
Environmental forensics, Diesel, Biomarker, Chemical fingerprint chromatogram, Diagnostic ratio, Multivariate statistical analysis techniques, Measuring Technologies, GC/MS