The USS Nimitz: Last of its Kind, Nuclear-Powered Aircraft Carrier to be Scrapped

Category Engineering

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The United States Navy has officially announced that the venerable USS Nimitz, an aircraft carrier with a half century-long legacy, will be scrapped. With the process of dismantling and disposal of the nuclear-powered aircraft carrier expected to cost the Navy up to a billion dollars, the USS Nimitz will be the last of its kind to be decommissioned and ultimately, scrapped.

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The United States Navy has officially announced that the venerable USS Nimitz, the namesake of her aircraft carriers, will be scrapped. This brings a close to the story of the ship that began almost 50 years ago when she entered service in 1975.

Breaking up a large warship is a challenging task in and of itself, but the Nimitz class has an added complication; the ships' nuclear power systems. The project will make it the second-only in the history of a nuclear-powered carrier being scrapped. The first was the Nimitz's sister ship, the USS Enterprise, the first nuclear-powered aircraft carrier ever commissioned and, ultimately, the first to be scrapped. She officially retired in 2017 and has only just begun the long, prolonged process of winding down and eventual disposal and storage of her nuclear material.

The USS Nimitz has 11 decks, a 4.5-acre flight deck, and a total length of 332.8 m (1,092 ft).

"The bulk of the Navy's past dismantlement and disposal work is comprised of comparatively low-cost projects—particularly submarines—with limited resource demands compared to a nuclear-powered aircraft carrier like CVN 65 [USS Enterprise], a multi-year project with a cost that will potentially exceed $1 billion," noted a 2018 Government Accountability Office report. To put that into perspective, a nuclear submarine costs about $26 million to scrap.

The decommissioning of the USS Nimitz marks the end of an era in which the United States operated the world's largest fleet of nuclear carriers.

According to the GAO, the Navy has decommissioned more than 130 nuclear-powered ships since 1990, which requires removing the nuclear fuel and reactor chamber. The Navy also developed nine nuclear-powered cruisers in the 1960s and 1970s in addition to carriers and submarines. USS Arkansas, the last of them, was decommissioned in 1998.However, scraping a 100,000-ton aircraft carrier is a significantly more challenging undertaking. It would be an understatement to suggest that the procedure is technically and administratively complex, so much so that the Environmental Protection Agency has an entire webpage describing how the process should work.

The nuclear fueld and reactor chamber of the USS Nimitz will be transported by barge and escorted by the Navy or Coast Guard.

The Department of Defense "maintains and monitors the radioactive parts," according to the EPA. The components are transported via barge, accompanied by Navy or Coast Guard escorts, to a disposal location by Department of Transportation guidelines. Certain reactor parts will be held in specialized vaults at the Department of Energy's Hanford, Washington facility.

"There is no reason civilians should ever encounter any exposure risk from nuclear submarines or the disposal sites that store the dismantled reactor compartments," the EPA adds.

The decontamination process of a nuclear-powered carrier is expected to take four to five years.

To this end, the Navy must devise a practical procedure for dismantling massive nuclear-powered aircraft carriers, no matter how complicated. The Navy intends to construct at least four more Ford-class ships, one of which will also be designated Enterprise, and its 11 current carriers, six of which, including Nimitz, have been in service for over 30 years. With the cost to scrap the former aircraft carrier bringing it in the ballpark of one billion dollars and a decontamination process that is expected to take four to five years, the USS Nimitz will be the last of its kind amongst nuclear-powered aircraft carriers to be decommissioned, and ultimately, scrapped. This marks the end of a half century-long legacy of the ship in service of the United States Navy.

Already, the USS Nimitz has surpassed its expected service life-span of 50 years.

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