Impact of New Diesel Fuels Used in Port Operations on Subsurface Quality

Transportation assume no liability for the contents or use thereof. The contents do not necessarily reflect the official views or policies of the State of California or the Department of Transportation. This report does not constitute a standard, specification, or regulation. DISCLOSURE The project was funded entirely under this contract by the California Department of Transportation. ACKNOWLEDGMENTS The author would like to acknowledge former graduate student Saurabh Shekhar for helping with the modeling during the early phases of this project and current undergraduate student Kreg Martin, who has been supported through this grant, for assistance with vadose zone modeling and preparation of graphs ii ABSTRACT Diesel is widely used as fuel for operations in the port of Los Angeles-Long Beach as well as for transport of goods to and from the port. Conventional diesel fuel contributes disproportional to air pollution (particulate matter, NO x , CO, and hydrocarbons). The arrival of low-sulfur diesel, which is already widely available in Japan and Europe, and other improvements in fuel and engine technology should greatly decrease the adverse impact of diesel on air quality. Examples of modifications are the use of diesel with ethanol as oxygenate (" diesohol "), biodiesel, and diesel with catalytic additives. Each fuel has some merits that need to be weighed against potential disadvantages. This proposal considers diesohol. Diesohol is already used in Europe and Brazil and is being investigated for wider use in the United States and Australia. In the past, scientists and decision makers were mainly concerned with the impact of diesel and gasoline on air quality. However, even under the best of circumstances release of diesel and fuel additives to the surface and subsurface environment cannot be ruled out. Accidental spillage and leakage may occur during production, transport, storage, handling, or use. In this study we quantified the impact of the release of a potential new diesel fuel on the movement and fate of contaminants in the aqueous phase of the unsaturated (vadose) and saturated zone of the subsurface. Existing software was modified to model subsurface flow in the vadose zone. The model accounts for the effect of surfactants (ethanol and other fuel additives) on flow properties, and the dissolution of diesel components (benzene in this case). The impact of ethanol on dissolution and degradation of fuels compounds and pre-existing organic contaminants in the groundwater has been analyzed using a model based on analytical solutions. The …