What is Gasoline?
Gasoline is a complex chemical mixture of refined petroleum produced from crude oil. Gasoline is primarily composed of carbon and hydrogen atoms, typically ranging from four-carbon compounds (C4; butane) to twelve-carbon compounds (C12; dodecane). This makes it a lighter petroleum product, produced from the earlier cuts of fractional distillation when crude oil is refined.
Gasoline contains high concentrations of benzene, toluene, ethylbenzene and xylenes (BTEX), petroleum hydrocarbons Fraction 1 and Fraction 2 (PHC F1, F2), and contains various proprietary additives by different suppliers for engine performance.
Gasoline does not contain significant amounts of polycyclic aromatic hydrocarbons (PAHs), which is often used to assess risk and is used as the remedial benchmark for spills and releases of petroleum products in the environment. However, gasoline contains naphthalene, a 2-ring PAH, and sometimes alkylated-naphthalenes, which are naphthalenes with one- or two- carbon groups attached, such a 1-methylnaphthalene. The ratios of naphthalene and 1- and 2-methylnaphthalene can be used as one of many tools to differentiate gasoline from diesel, which has much higher concentrations of naphthalenes.
Where is gasoline found in the environment?
Most often environmental investigations relating to gasoline will be as a result of releases from storage tanks and pipework, particularly at sites of old gas stations where underground storage tanks and pipes can leak. The design of underground storage tanks has been updated over the years to include more stringent safety standards to prevent leaks. These sites are often located in urban and residential areas. In addition, spills relating to transport, for example via tanker trucks may be an emergency response action relating to diesel.
Gasoline impacts from gas stations make this an urban contaminant with moderate mobility in the subsurface, with the possibility of reaching the groundwater table. Gasoline is a light non-aqueous phase liquid (LNAPL), meaning it will not mix with water and will float on top.
- Legal Sampling
- Chain of Custody
- Study Design
- Data Analysis and Visualization
- Data Wrangling
- Multivariate Statistical Analysis
- Principal Component (PCA); Hierarchical Cluster (HCA)
- Science Communication
- Data Science/Big Data
- Multidimensional Gas Chromatography (GC×GC)
- Source Apportionment
- Chemical Fingerprinting
- Diagnostic Ratios
- Fate and Transport
- Arsonous Wildfires