Source apportionment in oil spill remediation.

Area of Science:

• Environmental Science
• Marine Biology
• Chemical Oceanography

Background:

• A 2007 Caño Limon crude oil spill impacted San Vicente Bay.
• Initial cleanup left residual oil on rocky shores, complicating remediation.
• Existing hydrocarbons from industrial activity posed a challenge for assessing cleanup efficacy.

Purpose of the Study:

• To evaluate the effectiveness of a biosolvent in removing residual crude oil from a marine environment.
• To differentiate between the spilled oil and pre-existing hydrocarbons.
• To determine the overall success of the cleanup operation.

Main Methods:

• A biosolvent derived from vegetable oils was applied to solubilize remaining oil.
• Sediment and rock samples were collected before and after treatment.
• Gas Chromatography-Mass Spectrometry (GC-MS) and Partial Least Squares (PLS) analysis were used for oil source apportionment and quantification.

Main Results:

• The biosolvent treatment reduced total hydrocarbon concentrations by approximately 90%.
• Analysis indicated a shift in hydrocarbon composition towards longer-chain compounds post-treatment.
• The contribution of Caño Limon crude oil to total hydrocarbons ranged from 0% to 74%.

Conclusions:

• The biosolvent demonstrated significant efficacy in cleaning residual crude oil from San Vicente Bay.
• The statistical source apportionment successfully identified the contribution of the spilled oil.
• The cleanup was deemed sufficient, rendering further remediation unnecessary.