Oil dispersant field evaluation Ixtoc 1 blowout, bay of Campeche, Mexico

Abstract

A chemical dispersant concentrate was aerially applied, at a rate of approximately 2 gal/acre (19 1 ha⁻²) to a crude oil slick emanating from the Ixtoc 1 well blowout.

Chemical analyses of dispersant collected on pans at the sea surface beneath the swath of aerially-applied dispersant, showed no appreciable change in chemical composition from that of dispersant samples taken from holding tanks in the spray plane.

Comparisons between oil concentrations in water at varying depths under the stick, determined before and approximately one hour after cispersant application, showed elevated concentrations of hydrocarbons in the water column.

Photographs and visual observations from the research vessel and the two aircraft involved in the test indicated that application of dispersant did not cause ‘herding’ (lateral displacement) of the crude oil slick.