Glen Clark spent his career deciding what happens to Navy ships nobody needs anymore, and when a 32,000-ton aircraft carrier finally went under the surface of the Gulf of Mexico on his watch, he did not reach for anything dramatic to describe it.

Glen Clark, deputy program manager for the Navy’s Inactive Ships Program Office, summed up the operation this way: “The Navy and Florida team performed flawlessly.” That is the kind of line you use about a spreadsheet closing out clean, not a warship going to the bottom of the ocean on purpose. Except that is exactly the point of it. Getting a ship the length of nearly three football fields to sink upright, intact, and in one specific spot is not something that happens by towing it out and opening a valve.

The ship was the USS Oriskany, an Essex-class carrier that launched F-8 Crusaders and A-4 Skyhawks over Vietnam and could hold up to 80 aircraft at once. By 2006 it had spent decades out of active service, parked in the Navy’s inactive fleet the way old warships tend to be while someone works out what to do with them. What the Navy and the state of Florida decided to do with this one was sink it on purpose, off Pensacola, as the largest artificial reef ever built from a single vessel. That takes a real sequence of steps, and most of it happens long before anyone hears the word “reef.”

Retiring the ship and finding it a state to land in

A ship does not get scuttled because somebody thinks it would make a good dive site. The Navy has to formally release it from its inventory, and a coastal state has to agree to take on the legal and environmental responsibility for whatever ends up on its seafloor afterward. For the Oriskany, that state was Florida, working jointly with the Florida Fish and Wildlife Conservation Commission and Escambia County’s marine resources division. That three-way agreement between the Navy, the state agency, and the county is why this particular carrier ended up off Pensacola instead of somewhere else on the Gulf Coast, and it is why the county still carries ongoing responsibility for monitoring the site today.

Cleaning a warship well enough to satisfy the EPA

Before the Oriskany could leave port, it had to be stripped down to something environmentally survivable, which turned out to be a much bigger job than draining a few tanks of diesel.

Fuel, oil, and the parts that come out first

Crews worked through 512 tanks and voids aboard the ship, removing fuels, oils, batteries, mercury, antifreeze, coolant, firefighting chemicals, and both black and gray wastewater until the vessel was, in the Navy’s own words, essentially petroleum free. More than 150 people worked this phase of the project, according to the contractor that ran it.

PCBs, asbestos, and the review nobody could skip

The harder problem was polychlorinated biphenyls, industrial chemicals baked into the ship’s 1950s-era insulation, gaskets, and electrical cable. The Navy’s plan to leave an estimated 700 pounds of solid PCB material aboard required a formal risk-based review by the EPA, including leaching studies and an outside science panel, before anyone could proceed. When the approval finally came through in February 2006, Stan Meiburg, the EPA’s deputy regional administrator at the time, put it plainly: “We are pleased to be able to work with the Navy and Florida in protecting our environment and moving this project forward.” It was the first approval of its kind, and it set the template other reefed Navy ships would follow after.

The one part of the flight deck that never made it to the bottom

Here is the detail that surprised me most while researching this. The actual wood decking bolted to the top of the flight deck had PCB concentrations too high to leave in place, so the Navy removed the wood decking entirely before the ship ever left Texas. Divers swimming across the flight deck today are looking at the steel understructure, not the actual surface those Vietnam-era jets launched from.

Moving it into position

Once the paperwork cleared, the Oriskany’s own journey had already been underway for over a year. It had been towed from a shipyard in Beaumont, Texas, through Corpus Christi, and up to Pensacola back in January 2005, where it then sat waiting on the EPA decision. In May 2006, tugboats finally pulled it the last stretch, out to the actual sink site roughly 22.5 nautical miles southeast of Pensacola Pass, at a top speed of 2 knots. Crews had already installed a four-point mooring system at the site itself, designed to hold the ship in the exact position it needed to be in before anyone set off a single charge.

Sinking it on a schedule, not by accident

On the morning of May 17, 2006, a Navy explosive ordnance disposal team detonated charges at 10:25 a.m., and the Oriskany took 37 minutes to sink stern first into 212 feet of water, landing upright on her keel roughly where the mooring system had put her. Navy divers went down to inspect the wreck within 24 hours. Recreational divers were told to wait 48. Both timelines held.

Who actually goes down to see it now

This is where the process stops being about engineering and starts being about the people who show up for it every season. The Oriskany’s flight deck sits somewhere around 145 to 150 feet down, with the bridge closer to 118 and the top of the island structure around 84. That range already sits past the point where most recreational certifications stop. Divers Alert Network puts the line at 130 feet: past that, and past the point of a direct ascent to the surface, you are in technical diving territory, with decompression stops, mixed gas, and training that goes well beyond a standard open water course.

Walt Hartley, a cave-certified dive instructor and owner of Dive30A who has made the trip out to the Oriskany five separate times, has described running trimix and staged decompression bottles just to reach parts of the wreck below the flight deck. “The sheer size and scale of this ship is literally mind-blowing,” he said of it, and that reaction is a big part of why the site earned the nickname “The Great Carrier Reef.” It is also why a small cluster of charter operators out of Pensacola and the surrounding Panhandle still run boats out to that same patch of water most mornings the weather allows, loaded with tanks, deco bottles, and divers who planned an entire trip around one specific wreck. The tourists snorkeling along the beaches nearby never see any of it. The divers who go down do, and for them, that is the whole point of getting on the boat.