Base de données de recherche des TNO

Régions: Inuvialuit Settlement Region

étiquettes: contaminants, environmental assessment, environmental impact, petroleum industry, active layer, soil, vegetation, snow accumulation, tundra ecosystems, human disturbance, sump site, bird sanctuary

Objectif(s): The aim of this study is to examine the structure of soil and ice in the active layer and permafrost, and the chemical composition of soil cores to evaluate the effectiveness of permafrost containment on abandoned sumps.

Description du projet: Since the 1970s, the oil and gas industry has drilled at least nineteen exploratory wells in the Kendall Island Bird Sanctuary. Observations at associated drilling mud-sumps have been made; however, there remains a paucity of field data describing site conditions. It is also appreciated that construction of the proposed Mackenzie Valley pipeline will stimulate the development of Niglintgak and Taglu fields, both located under and adjacent to the Kendall Island Bird Sanctuary. Information on the environmental conditions in the bird sanctuary, the behaviour of contaminants in permafrost terrain, and tundra ecosystem responses to disturbance caused by humans are necessary to manage the impacts of industrial activities and to determine possible methods for mitigating disturbance effects. This data will help decision-makers to review and plan for future permafrost containment activities. Work conducted as part of this research project complements that of a project being undertaken by Dr. Steven Kokelj on variation in plant community composition, the effect of vegetation on winter snow accumulation and ground-thermal conditions, and the potential relationships between vegetation type and these conditions. Data will be collected to assess environmental conditions at well sites and sumps abandoned during the 1970s and 1980s in the Kendall Island Bird Sanctuary. Soil core samples will be collected at a number of locations at the following sump sites to examine the nature of the soil and ice in the permafrost and active layers in the sumps: Taglu D-43 (69 deg 22' 13.8" 134 deg 57' 0.4"), Taglu H-54 (69 deg 23' 20" 134 deg 58' 5.9"), Taglu C-42 (69 deg 21' 5" 133 deg 56' 49.9"), Niglintgak B-19 (69 deg 18' 11.2" 135 deg 18' 19.1"), Kumak K-16 (69 deg 15' 32.8" 135 deg 3' 58.3"), Kumak E-58 (69 deg 17' 29.4" 134 deg 14' 55.3"), and Kumak J-06 (69 deg 15' 36" 135 deg 00' 58"). To obtain samples, six holes will drilled at each site using a 2" inside diameter CRREL core barrel. A specially designed portable drilling frame and a gas-powered auger will be used, which should allow drilling to depths of 3-5m. Core samples will be maintained frozen through drilling, storage and transportation to the university geochemistry research laboratory. Chemical analysis will then be performed on the soil cores to evaluate the effectiveness of the permafrost containment to limit migration of drilling mud additives away from the sump. In addition, deep temperature measuring cables will be installed in selected boreholes and equipped with data acquisition systems to monitor the temperature profiles at greater depths than is possible currently. Core holes will be then sealed by being backfilled to the surface with bentonite clay. The research team will travel from base camp (either at Camp Farewell or Inuvik) to the field sites by truck on the ice road and then by snowmobile, where necessary.