SGS Hydrocarbon Forensics

SGS introduces our expert-driven hydrocarbon forensics service to help you characterize oil and fuel contamination, assign source and age, and assess liability.

Oil and fuel contamination can be a complex and expensive issue to resolve. Hydrocarbon forensics involves the reconstruction of historical spill events to determine the contamination, age, and sources of that contamination. Our forensics offering utilizes decades of expertise, standardized measurement methods and detailed reports to help you determine sources of spills and allocation of liabilities.

Spills and sources of contamination are determined from past or current events using a tiered approach. SGS offers Tier 1 analysis routinely to identify components prior to employing sophisticated Tier 2 and Tier 3 analyses. Our optional interpretation service provides expert reports on the data generated.

Tier 1 Fingerprinting

Tier 1 fingerprinting provides the identification of the product found at a site using GC-FID methods modified from EPA 8015. Our custom optimizations use extended chromatographic runs to improve product component separation. Our forensics experts interpret these patterns using internal and external data sources to aid the classification of source such as gasoline, diesel, crude oil, mineral oil etc. Figure 1 shows a typical overlay for comparison of source product with the spill sample or a product from the SGS library compared to the sample. Our extensive library of sources means we’re able to provide you with clear insights from Tier I testing alone.

Figure 1: Overlay of Sample and library products.

Tier 2 Analysis

When there are multiple sources of contamination at a site, and significant weathering, Tier I qualitative analysis may not be sufficient. We work with you to move to Tier 2, specific quantitative analysis of the samples for multiple hydrocarbons.

PIANO

SGS offers hydrocarbon classification analysis – Paraffins, Isoparaffins, Aromatics, Naphthene’s and Olefins (PIANO) by EPA 8260D Modified GC-MS to determine the composition of the fuels found in groundwater plumes (LNAPL’s) and spills. Additionally, gasoline additives are measured (oxygenates) along with the alkylated leads. Diagnostic ratios are also presented to provide interpretation of the compositional analyses. PIANO fractions are also calculated from the data for interpretation. The data derived from this fingerprinting analysis can be utilized for age-dating of spills.

Oxygenates

Characteristic additive compounds known as oxygenates are also measured in conjunction with the PIANO analysis. As the composition of these additives have varied with time, they provide a valuable mechanism to age date the fuels.

Tier 3 Specialty Analysis

Alkylated Lead analysis:

Alkylated lead analysis by SW846 8270 elucidates and ages leaded gasoline spill sites.  SGS analysis consists of 5 alkylated isomers of lead. Figure 2 shows the Alkylated Lead isomers we analyze at SGS.

Figure 2: Chromatogram of Alkylated Lead Isomers

Alkylated PAHs and PACs

We also offer a full suite of Alkylated PAHs and polycyclic aromatic compounds (PAHs) including thiophenes for petrogenic versus pyrogenic fingerprinting. Visit our <link to Specialty hydrocarbons> page for more information on how to add these targets to your fingerprinting projects.

Optional DATA Interpretation

Whether you want to take our high-quality data and glean insights from it, or whether you need our experts to help you understand the data, we have you covered. Our forensics experts can provide interpretation services to help make sense of the analytical data we generate. Alternatively, we can provide raw data for interpretation.. Raw instrument data files are provided to youto generate additional rvisual representations  in various formats and interpretations.

Our expert interpretation service includes overlays of chromatograms, diagnostic ratios, radar plots and interpretation of the generated data with historical site information provided by tyou. A typical radar plot for comparisons is shown in Figure 3. Our data presentation includes the PIANO compositions and Diagnostic Ratios along with the routine data tables. Table 1 below shows the Diagnostic ratios for a gasoline sample.

Figure 3: Radar Plot – Gasoline Standard compared to a Sample.