A layer of redwood and a set of upper windows were set to be the last items removed on July 18. The major reason for the cleanup was to remove siding layered in toxics, the last piece of which came off on July 11, said project manager Bryce Bartelma in an email.
"It certainly is an interesting structure," said Moffett museum curator Bill Stubkjaer. "I'd be a lot happier if I knew there was plan for getting siding back on it."
With a birds-eye view of the Bay Area, workers rappelled down the sides of the 200-foot-all monolith to remove tiles of siding, a layer of redwood underneath it and 4,638 glass windows. Built inside was possibly the largest scaffolding in local history, enough to fill 225 semi-trucks, with elevators.
Countless tons of a 1930s product called Robertson Protected Metal were removed, a corrugated steel siding encapsulated in layers of toxic PCBs, lead and Asbestos, with each piece weighing up to 70 pounds. The tiles were wrapped in plastic and transported to Grassy Mountain landfill in Utah. The frame was cleaned with pressurized water and coated with a silver paint said to have lasted decades on other structures.
The environmental cleanup reportedly cost $32 million, an increase from the $26 million initially reported. UK-based AMEC Environmental did the work under a contract with the United States Navy.
The hangar was built during the Great Depression to hold the U.S.S. Macon, a massive airship used by the Navy between 1933 and 1935. The Macon held several small planes that could be deployed from its belly for long range scouting off the Pacific Coast. After 50 flights it hit a storm off the coast of Point Sur in 1935 and sank near Monterey Bay. Two of 83 sailors on board died.
Along with its sister the USS Akron, it remains the largest helium airship ever built, with a length of over two and half football fields, 785 feet.
Hangar One is set to stand bare indefinitely as a symbol of government dysfunction, say those working to save it. The founders of Google have offered to put up as much as $45 million for new siding in exchange for an agreement to allow them to use a portion of the hangar for a fleet of private planes. But owner NASA has yet to accept the offer and instead has expressed interest in offloading the structure and the entire Moffett Federal Airfield in a process that could take years.