TITLE:
Resolution of Suspected Tank Release of Diesel Fuel Using Diagnostic Compounds and Biomarkers
AUTHORS:
Jun Lu, Deborah Dees Kowalewski
KEYWORDS:
Tank Leak, Seismic Wave, LNAPL Mobility, Diagnostic Compounds, Biomarkers, Source Identification and Correlation
JOURNAL NAME:
Journal of Environmental Protection,
Vol.7 No.3,
February
29,
2016
ABSTRACT:
During
a routine inspection in a petroleum product terminal, hydrocarbon staining was
found in soil along the perimeter of a diesel fuel tank. As the observation was
made a few days after a magnitude 5.1 earthquake in the general area of the
terminal, the hydrocarbon staining in the soil was suspected to be a result of
a leak from the tank. The observation triggered an immediate tank inspection,
which included examination of tank exterior, piping and connections; pressure
testing; wall thickness gauging; and an inventory check. Results of the initial
inspection suggested that there were no integrity issues with the tank. Before
more vigorous and more disruptive inspections were conducted, chemical
fingerprinting was conducted to assess the nature of soil staining and
potential connection with the “suspected” tank leak. Samples were collected
from the site, including a diesel fuel sample from the tank, a light
non-aqueous phase liquid (LNAPL) sample from the monitoring well in the
immediate vicinity, and representative soil samples from the perimeter of, and
beneath, the tank. A tiered laboratory analytical approach was taken, which
included initial gas chromatography-flame ionization detector carbon chain
analysis and final gas chromatography-mass spectrometry or detailed fingerprint
analyses. Based on the results of initial inspection, knowledge of LNAPL
mobility in response to earthquake seismic waves, and chemical fingerprints of
representative samples, it was determined that the soil staining was not a result
of suspected tank release but remobilization of hydrocarbons from the
historically impacted soil beneath the tank to the soil along the perimeter of
the tank.