It took years of haggling and $480 million to create the U.S.'s newest wilderness sanctuary Headwaters Forest Reserve, a forest so serene that the sound of a hummingbird can startle the occasional hiker. That silence could be shattered by huge Chinook helicopters hauling away Douglas firs and redwoods if the Pacific Lumber Co. wins a court battle Wednesday over the so-called "Hole in the Headwaters.'' A lawsuit to block logging in the preserve's lone remaining unprotected area was filed by the Sierra Club and the Environmental Protection Information Center.