Coast Guard Strengthens Presence North of Alaska BARROW, Alaska - When the United States Coast Guard arrived in this remote corner of the Arctic this month to begin its biggest patrol presence in the waters north of Alaska, only one helicopter hangar was available for rent, and it was not, to put it mildly, the Ritz. Built by someone apparently more familiar with the tropics than the tundra, the structure had sunk several feet into the permafrost, with the hangar entrance getting lower as the building sank. Squeezing two H-60 helicopters into the tiny space? Think of parallel parking a stretch limousine. And for this - the only game in town, take it or leave it - the owner demanded $60,000 a month, a price that made Coast Guard leaders gasp. "Not perfect, but you've got to learn to do it somehow," Josh Harris, a Coast Guard aircraft mechanic, said as he stood surveying his first and not entirely straight attempt at towing in an aircraft. In the land of the midnight sun, the Coast Guard's learning curve is steep indeed. The effort, called Arctic Shield, began this month as a pilot project combining search and rescue responsibilities with disaster response and maritime safety enforcement. It will presumably only expand, Coast Guard officials say, as global warming melts these once ice-locked waters. With air operations based here in the nation's northernmost community, more than 300 miles past the Arctic Circle, the assignment is expensive, logistically complicated to supply and far from backup should things go wrong. "The Arctic has been identified as a priority," said Cmdr. Frank McConnell, the operations coordinator for Arctic Shield, which includes in its initial phase two Coast Guard cutters and two smaller ships, in addition to the two helicopters that will be stationed here in Barrow. The first of 25 pilots, along with support crews, mechanics and communications personnel, began rotating through Barrow this month on three-week tours. "There's a lot to learn," Commander McConnell said. But the operation also introduces a new element to the complex and rapidly evolving portrait of what this vast, stark corner of the nation is becoming: a duty mission. Shell Oil, driven by a search for profits, is preparing for its first drilling operations next month in two spots northeast and northwest of Barrow. The environmental group Greenpeace, vehemently opposed to Arctic drilling and its risks, has sent its own ship north for what the group says is a research project. Freight haulers have been streaming through, seeking a shortcut across the top of the world, and passenger cruise ships loaded with tourists have started to stake out new routes. Shell plans to have a daily Boeing 737 flight between Barrow and Anchorage, Alaska's largest city, just to ferry personnel. The company will also have its own helicopter service from Barrow - population 4,000 - to the ocean drilling sites. The Coast Guard, in conjunction with the Navy and other agencies, is planning an oil spill cleanup response exercise on the water early next month. "More traffic up there means more people," said Cmdr. Kevin Riddle, the captain of the Coast Guard cutter Alex Haley, which was preparing to deploy north this month from its base in Kodiak, Alaska. With cruise ships full of hundreds of passengers potentially needing rescue, tanker ships going adrift in coastal areas or getting stuck in sea ice, and the energy boom itself, Commander Riddle said, once largely empty waters are getting more crowded. "If we don't have a presence up there," he said, "how are we going to respond adequately?" The Coast Guard, a branch of the Department of Homeland Security, has a tradition of derring-do in patrolling the nation's waters and an especially rich tradition here in Alaska, where huge areas of land are tied to the sea, with no roads to the broader world. But even as the Coast Guard crews, mostly based out of the base in Kodiak, 940 miles south of here, began its first daily patrol flights from Barrow a week ago, the uncertainties of the mission remained huge. A cold winter left the sea ice intact longer and closer to shore this year. That delayed the potential drilling window that Shell had been granted in its permits. A Shell barge being fitted in Bellingham, Wash., which the company says would be able to control and contain oil spills, has also been delayed by construction and permit approvals and will not be in the Arctic until August, a company spokesman said. And a coalition of environmental groups filed a lawsuit this month in Federal District Court in Juneau saying federal regulators had erred in approving Shell's oil spill response plans. Even the specific protocols of the Coast Guard's role as a police authority, in the event that environmental protests of drilling operations escalate, remain unclear. This year, a federal judge granted Shell a one-kilometer protected zone around its Arctic operations. A spokesman for Greenpeace, Joe Smyth, in a telephone interview from the group's ship, the Esperanza, said the group planned to map the seabed at Shell's drilling sites and be gone before Shell arrived. But he declined to specify what Greenpeace would do after that. "We expect there not to be any issues from our end," Mr. Smyth said. Asked during a community meeting with elected officials in Barrow this month what would happen if a civilian vessel crossed into Shell's protected zone, Commander McConnell acknowledged that details were still being worked out. A Coast Guard spokeswoman said in an e-mail last week, "Any action that disrupts safe navigation or endangers lives at sea will be appropriately responded to and investigated." Many Coast Guard personnel said uncertainty in any new mission was normal. They improvise and they adapt, they said. "Aluminum foil and tape," said John Wolfen, an aviation maintenance technician, describing part of the kit he was taking to block his windows from late-night glare. But unlike the summer sun, the beleaguered Barrow hangar is still going down. "As the building sinks, the height of the hangar decreases," Veronica Colbath, a Coast Guard spokeswoman, said in an e-mail.