Hydrogeologic controls on migration of an oil-spill plume in alluvial deposits near Fort Collins, Colorado

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:5827447

Waltz, J P; Boyle, R E

During 1979 a fuel oil spill of approximately 50,000 gallons resulted from leakage out of underground storage tanks directly into a shallow alluvial aquifer at an industrial site near Fort Collins, Colorado. When the spill was discovered and test holes drilled in November of 1979, the oil plume had a tear-drop shape and was approximately 300 feet in average diameter. Additional test holes drilled tow years later show a relative stabilization of the plume at an average diameter of less than 500 feet but with irregular boundaries. Despite a relatively simple geologic setting of alluvial terrace deposits on top of a beveled shale bedrock, plume migration appears to have been significantly affected by variations in alluvial stratigraphy. Plume migration has also been affected by variations in the groundwater potentiometric surface resulting from development of extensive paved parking lots, irrigated landscapes, and other changes in land use at the site. To evaluate factors affecting plume migration, data from over 200 logged test holes at the site were used to prepare maps of the groundwater piezometric surface and bedrock topography. Although oil thicknesses in early stages of the plume development locally exceeded 30 inches, redistribution of oil within the plume over relatively short periods of time frustrated conventional efforts to recover significant quantities of the fugitive oil. Recent monitoring of the plume indicates the oil to be naturally contained by hydrodynamic and small-scale stratigraphy traps within the alluvium.

• Research Organization: Colorado State Univ., Fort Collins (USA)
• OSTI ID: 5827447
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020900 -- Petroleum-- Environmental Aspects
520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ALLUVIAL DEPOSITS
AQUIFERS
COLORADO
FEDERAL REGION VIII
GEOLOGIC DEPOSITS
GROUND WATER
HYDROGEN COMPOUNDS
HYDROLOGY
MEASURING INSTRUMENTS
MIGRATION
MONITORS
NORTH AMERICA
OIL SPILLS
OXYGEN COMPOUNDS
PATTERN RECOGNITION
POLLUTION
USA
WATER
WATER POLLUTION
WATER POLLUTION MONITORS