Ground water contamination at Bemidji, MN

Ground water contamination at Bemidji, MN Part 1: Younis Altobi http://www.epa.gov/oilspill/photo.htm

Outline: Younis Altobi • Introduction • Significance • Description of site • Study objectives • Data • Methodology • Data analysis • Data interpretation • Results • Limitations • Future Work http://www.epa.gov/oilspill/photo.htm

Introduction • Most oil pipelines leak at least once during their life span. • ~14,000 spills a year are reported in the U.S. • Spills pose hazards to: • marine and human life • natural and man-made resources • Each spill’s environmental impact depends on its spreading rate. http://www.epa.gov/oilspill/photo.htm

Significance Problem: • Treatment and remediation challenges: • Time consumption • Costs in training and equipment • Inaccurate site assessments Possible solution: • Apply GIS techniques to monitor and model: • Contaminant distribution with time. • Contaminant migration with time. • Contaminant concentration with time.

Description of Site • NW Bemidji, MN • In 1979, a pipeline burst, spilling ~11,000 barrels of crude oil. • Contaminated subsurface sediment and ground water. http://mn.water.usgs.gov/bemidji/gif/locatn-1.jpg

Study Site http://mn.water.usgs.gov/bemidji/gif/fig4.jpg http://mn.water.usgs.gov/bemidji/

Study Objectives Using GIS techniques and utilizing Arc Hydro Groundwater Data Models devised by Gil Strassberg and Suzanne Pierce (CRWR) • 2-Dimentional surface-ground water interaction data model using aquifer, stream networks, aquifer recharge and contaminant transport. • 3D geological framework of the aquifer using wells, coring and test data. • Model groundwater movement through out the aquifer. • Model hydrocarbon migration since the 1979 oil spill through out the aquifer. • Model the aquifer hydrologic unit to determine the effects of lithology and porosity on water and hydrocarbon movements. • Produce a 3D distribution profile of the hydrocarbon plume across the site.

Objectives accomplished • 3D geological framework of the aquifer using water wells and coring. • Model hydrocarbon migration since the 1979 oil spill through out the aquifer. • Produce a 3D distribution profile of the hydrocarbon plume across the site. • 3D surface topography of the site. • Ground water level changes through time. • Oil level, thickness, and concentration through time.

Data • Wells (over 200 total wells) • Water level • Oil level • Oil thickness • Oil concentration (Benzene and Toluene) • Core • Elevation Data source: http://mn.water.usgs.gov/bemidji/data.html

Data Analysis • Select wells from area of interest (north pool). • Create a surface elevation. • Produce a 3D projection of core lithologies. • Using well attributes, we distributed: • Water level • Oil level • Oil thickness • Oil concentrations • Time Frame (3 periods)

Data Analysis: Surface elevation • Surface interpolated from selected surface elevation points distributed across the study site.

Data Analysis: Cores

Data Analysis: Attribute Tables

Acknowledgments • Gil Strassberg (CRWR) • Dr. David Maidment • Suzanne Pierce (UTDoGS) • Geoff Delin and Todd Anderson • http://mn.water.usgs.gov/bemidji/

Ground water contamination at Bemidji, MN