A Large-Scale Experimental Investigation of theImpact of Ethanol on Groundwater ContaminationEPA Grant Number: R831276C016Subproject: this is subproject number 016 , established and managed bythe Center Director under grant R828598(EPA does not fund or establish subprojects; EPA awards and managesthe overall grant for this center).Center: Gulf Coast HSRC (Lamar)Center Director: Ho, Tho C.Title: A Large-Scale Experimental Investigation of the Impact of Ethanolon Groundwater ContaminationInvestigators: Rixey, William G.Institution: University of Houston - University ParkEPA Project Officer: Krishnan, S. BalaProject Period: December 1, 2003 through November 30, 2004Project Amount: Refer to main center abstract for funding details.RFA: Gulf Coast Hazardous Substance Research Center (LamarUniversity) (1996)Research Category: Gulf Coast Hazardous Substance Research CenterDescription:Objective:Methyl tertiary-butyl ether (MTBE) contamination in groundwater andsurface water in the United States is widespread and considered a majorthreat to drinking water resources. The fuel oxygenate is therefore beingphase out, and ethanol is the leading oxygenate to replace MTBE. Toprevent a repeat of the problems associated with MTBE, the potentialimpacts to groundwater quality resulting from the inevitable releases ofethanol-blended gasoline must be understood. Typical scenarios includeleaks of ethanol-blended gasoline from underground storage tanks,accidents with railroad cars or tanker trucks and spills of neat ethanol atdistribution terminals. One of the major concerns regarding ethanolreleases is its potential to cosolubilize benzene and other aromaticcompounds in groundwater.There have been some prior laboratory studies that have addressed thecosolubilization of benzene by ethanol, including research by Dr. Rixey atthe University of Houston. However, a larger-scale investigation is neededto more thoroughly address the environmental implications associated withthe use of ethanol additive fuels.The objective of this research is to simulate spill scenarios in the field witha controlled pilot-scale system. This proposed research will merge theexpertise of two universities (Rice and the University of Houston) bystudying the impacts of ethanol in the Experimental Controlled ReleaseSystem (ECRS), a pilot-scale tank designed specifically to testenvironmental remediation techniques on a scale that more closelyresembles that in the field.Approach:Dr. Bedient at Rice University has considerable expertise in conductinglarge-scale studies and has recently used the ECRS to bridge laboratorystudies and field studies in a study sponsored through GCHSRC thatinvestigated the bioremediation of a PCE DNAPL source. Dr. Rixey hasconsiderable, and complimentary, laboratory experience that includesrecent research specific to the impact of ethanol on groundwater quality.Expected Results:The proposed research program will include the following activities:1. Simulate the impact of ethanol on groundwater contamination incarefully controlled, large-scale laboratory experiments and complementarybench-scale experiments.2. Investigate three important spill scenarios:(1) gasoline containing ethanol (i.e., gasohol);(2) neat ethanol onto existing gasoline contamination;(3) fuel-grade ethanol into the subsurface w/o existingcontamination.3. Assess the impact of ethanol on the potential enhancement in BTEXplumes and sources of NAPL contamination.4. Analyze and evaluate experimental results through a joint modelingeffort.Supplemental Keywords:POLLUTANTS/TOXICS, RFA, Scientific Discipline, Waste, Water,Chemicals, Contaminated Sediments, Drinking Water, Ecology andEcosystems, Environmental Chemistry, Environmental Engineering,Hazardous, Hazardous Waste, BTEX, MTBE, NAPL, benzene,contaminated groundwater, contaminated sediment, contaminated soil,drinking water contaminants, ethanol, gasoline leaks, groundwater,groundwater remediation, hazardous waste storage, hazardous wastetreatment, leaking underground storage