Interesting Articles:
Dispersants and effects of:
Mother Jones article on how dispersants can allow oil to migrate further into sand:
http://www.motherjones.com/blue-marble/2012/11/bps-dispersant-makes-oil-immortal
And open access article by Alissa Zuijdgeest and Markus Huettel documenting the research:
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050549?imageURI=info:doi/10.1371/journal.pone.0050549.g001