| Summary: | Progress Code: completed Statement: Please see the Permeability worksheet in the Master_Permeability.xls spreadsheet for individual data points marked bad, as well as notes regarding why they were bad. In general, these data points were marked bad for one of three reasons. The first occurred when the sack hole was drilled too deep. Within the bottom few centimetres of ice the ice became too permeable to block the horizontal component of flow and insert the pressure transducer before the hole had filled to freeboard. Inserting the packer and deploying the pressure transducer typically took between 5 and 10 seconds, which on occasion was not fast enough. The second problem we encountered was a bottom slush layer below sites 7 and 8. At the beginning of each day a hole was drilled into the slush layer to verify the fluid flowed in and equalized with the freeboard as quickly as would be expected in the ocean. Additional data analysis, potentially including modelling work, will be required to determine the effect of this slush layer on the values recorded. The third problem occurred due to the rafted nature of floes. On occasion, attempts to auger through the ice for thickness measurement resulted in the discovery of a raft below the ice. In particular this was a problem at site 3. Following the discovery of this problem the presence of rafting became criteria in determining an appropriate worksite. Auger holes were created while scouting for worksites to look for rafting. Potential worksites with rafting were rejected in favour of another area. A 9 cm diameter Kovacs corer was used to drill holes partially through the ice. The core was removed, creating a pressure head in the hole. Packers made of ABS tubing wrapped with foam to create a tight seal were inserted into the holes to block the horizontal component of flow. A "Levelogger", which is a pressure transducer for monitoring well-water, created by Solinst, was then inserted into each hole to record the change in water level over time. Each Levelogger was ...
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