Environmental Health - Toxic Substances
U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting Charleston South Carolina March 8-12, 1999--Volume 3 of 3--Subsurface Contamination From Point Sources, Water-Resources Investigations Report 99-4018C
Impacts of Remediation at the Bemidji Oil-Spill Site
By William N. Herkelrath
The U.S. Geological Survey has conducted a multidisciplinary investigation of the fate and transport of subsurface petroleum hydrocarbons at the site of crude-oil spill near Bemidji, Minnesota, since 1983. For 19 years, the Bemidji site provided a unique natural laboratory for scientists to study a subsurface oil spill that was virtually undisturbed. However, in order to ensure compliance with the law, Minnesota State authorities have recently mandated oil-recovery remediation of the site. The aim of the remediation is to remove the separate-phase oil that is presently located near the water table. In this paper, simple models were used to obtain first-order estimates of how much subsurface oil is now present at the Bemidji site, and how much oil is likely to be recovered during the remediation. These preliminary results indicate that about 241,000 liters of oil are now present, and about 41,000 liters (17% of the present oil volume) will be recovered during the remediation.