Presentation
Shoreline Response: Lessons from the BIOS and ITOSS Field Experiments and Long-Term Spill Studies
DescriptionTwo ground-breaking international controlled field trials significantly advanced understanding the behaviour of stranded oil and of shoreline treatment methods. The lessons learned from these field trials and from long-term post-spill studies provide science-based advice and recommendations on in situ and other treatment options that continue to be applicable today.
The 1981-1982 shoreline component of the Baffin Island Oil Spill (BIOS) field experiment was conducted in a low energy, Canadian high arctic environment. An estimated 5.3 m3 of Lago Medio crude stranded on a 250-m mixed-sediment beach following a controlled nearshore release. Despite the low-energy conditions, within 10 days this volume was reduced to 3.1 m3, primarily due to refloating of mobile oil by tides. Sampling during 1981 detected no unacceptable toxicity levels in benthic sediments or suspended particulates in the water column. Monitoring over the following 20 years documented the formation and decay of an asphalt pavement and the biodegradation of surface and subsurface oil. The 1997 In-situ Treatment of Oiled Sediment Shorelines (ITOSS) field trials conducted in Svalbard, Norway, focused on in situ shoreline treatment methods (bioremediation, tilling (mixing), and sediment relocation) applied to large intertidal plots oiled with an intermediate fuel oil. Again there were no unacceptable toxicity levels in benthic sediments or suspended particulates in the water column off the treated beaches, nor any evidence of long-term toxic effects more than a year after treatment whereas oiled sediments from the untreated beach continued to generate a toxic response. Bioremediation by adding fertilizer significantly increased the rate of biodegradation. The key lesson learned was that intervention with in situ treatment can significantly reduce the volume of stranded oil in the very short (days) and medium (week-months) time frames. When considering levels of effort and waste generation, in situ methods often offer a better solution and are more operationally practical and efficient than physical removal, particularly in remote locations. The results of these controlled real-scale experiments are compared to data from long-term post-spill studies.
The 1981-1982 shoreline component of the Baffin Island Oil Spill (BIOS) field experiment was conducted in a low energy, Canadian high arctic environment. An estimated 5.3 m3 of Lago Medio crude stranded on a 250-m mixed-sediment beach following a controlled nearshore release. Despite the low-energy conditions, within 10 days this volume was reduced to 3.1 m3, primarily due to refloating of mobile oil by tides. Sampling during 1981 detected no unacceptable toxicity levels in benthic sediments or suspended particulates in the water column. Monitoring over the following 20 years documented the formation and decay of an asphalt pavement and the biodegradation of surface and subsurface oil. The 1997 In-situ Treatment of Oiled Sediment Shorelines (ITOSS) field trials conducted in Svalbard, Norway, focused on in situ shoreline treatment methods (bioremediation, tilling (mixing), and sediment relocation) applied to large intertidal plots oiled with an intermediate fuel oil. Again there were no unacceptable toxicity levels in benthic sediments or suspended particulates in the water column off the treated beaches, nor any evidence of long-term toxic effects more than a year after treatment whereas oiled sediments from the untreated beach continued to generate a toxic response. Bioremediation by adding fertilizer significantly increased the rate of biodegradation. The key lesson learned was that intervention with in situ treatment can significantly reduce the volume of stranded oil in the very short (days) and medium (week-months) time frames. When considering levels of effort and waste generation, in situ methods often offer a better solution and are more operationally practical and efficient than physical removal, particularly in remote locations. The results of these controlled real-scale experiments are compared to data from long-term post-spill studies.
Event Type
Paper
TimeThursday, May 16th9:00am - 9:20am CDT
Location291-292
Response