A coiled tubing string may be run into the casing near the bottom of the vertical well and nitrogen gas pumped into the well if the well loses pressure before a complete well test can be run, an operation which would require additional equipment, which would remain on site during the nitrogen pumping operation, expected to last approximately 14 days.
If two weeks of gas assist does not provide a complete well test, the nitrogen will be discontinued and a submersible pump system will be installed, requiring a workover rig, Great Bear said.
"Tubing (probably 3 or 4 inch diameter), packer, and a submersible pump will be run into the hole to continue the well test until stable production rates are obtained or until a decline curve can be determined (but not to exceed 180 days)," the company said.
Traffic volume on Haul RoadGreat Bear said it expects flow testing at the Alcor and Merak wells to begin in October and November. The volume of traffic on the Haul Road, assuming 1,000 barrels per day, based on an analogue with the Eagle Ford play in south Texas, would mean some seven tanker trips a day between the drill site and the Prudhoe Bay unit daily, "diminishing rapidly over the six month period as production declines," the company said. Great Bear said it cannot say for sure what the volume of truck traffic associated with an extended production test would be, but "based on other unconventional wells, it is fairly certain" the volume would peak during the initial 15 days of the flow test and continue to decrease over time as the "initial flowback water production rate" decreases as "the water flow transitions into (hopefully) oil flow," Great Bear said. "As additional wells are drilled and tested there will likely be simultaneous testing going on. Given the likely gap between wells, and the potential decline rate, Great Bear estimates that the maximum number of tanker trips aggregated from all wells at any given day is approximately 20," the company said.