Fate and Effects of Crude Oil Spilled on Subarctic Permafrost Terrain in Interior Alaska: Fifteen Years Later

• Main Authors: Collins, Charles M., Racine, Charles H., Walsh, Marianne E.
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
• Format: Text
• Language: English
• Published: 1993
• Subjects: Hydrology; Limnology and Potamology; Solid Wastes Pollution and Control; Water Pollution and Control; *ENVIRONMENTAL IMPACT; *OIL SPILLS; *PERMAFROST; *CRUDE OIL; MEASUREMENT; DEGRADATION; ALASKA; SUBSURFACE; FORESTS; VEGETATION; ASPHALT; COLD REGIONS; ENVIRONMENTAL FATE; permafrost; Subarctic; Alaska; Cottongrass
• Online Access: http://www.dtic.mil/docs/citations/ADA270030; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA270030

The effects of two large experimental oil spills conducted in the winter and summer of 1976 in the permafrost-underlain black spruce forest of interior Alaska were assessed 15 years after the spills. Effects on the permafrost, as determined from measurements of active layer thaw depths and of the total amount of ground subsidence, were far more pronounced on the winter spill because it had a larger area with oil on the surface. The winter spill also had a more drastic effect on the vegetation. Where the black, asphalt-like oil is present on the surface, black spruce mortality is 100% and there is very little live vegetation cover, except for cottongrass tussocks. Changes in oil chemistry vary with depth; surface samples show signs of microbiological degradation, whereas some subsurface samples taken just above the permafrost show no evidence of degradation and still contain volatiles. Black spruce forest, Crude oil, Oil spills, Terrestrial oil spills, Interior Alaska, Permafrost.