The 800-ton-capacity Sun 800 was purpose-built for the construction of the Hughes Glomar Explorer, a deep-sea drill-ship platform, built in the mid-1970s for the U.S. Central Intelligence Agency, to retrieve a Soviet ballistic-missile nuclear-submarine wreck from the Pacific Ocean seabed—three miles down. The sub had sunk in 1968.

The covert mission was named Project Azorian. The 618-ft-long and 115-ft-wide ship, built in plain sight by Sun Shipbuilding and Drydock Co. at a cost of more than $350 million, needed a cover story. So, the CIA convinced the world that billionaire industrialist Howard Hughes paid for the 36,000-ton vessel to mine manganese modules from the ocean floor. The Sun 800 placed the gimbal on the ship. The Sun's 630-ton lift was the heaviest part in the entire construction process of the ship and was the primary reason the derrick barge was built. 

According to a New York Times article, published on March 19, 1975, the Glomar Explorer recovered about a third of the sub and the bodies of more than 70 Soviet crew, but it didn't raise the missiles or the sub's code room. The lifting apparatus broke apart about 9,000 ft down, and the majority of the sub fell back to the ocean floor. The Glomar Explorer was sent to the scrap yard in 2015.

Donjon Marine Co. Inc. bought the Sun 800 in 1993, increased the capacity to 1,000 tons and renamed it the Chesapeake 1000, nicknamed "Chessy."

Chessy's other projects may not be as cloak-and-dagger as the Glomar Explorer job, but they are absorbing. In a series of risky, late-night maneuvers in summer 2016 in Manhattan, the derrick barge successfully lifted 19 two-story modules, ranging from 500 to 788 tons, from the tidal East River, placing each on top of the FDR Drive parkway. They were used in the construction of a 960-ft-long laboratory building for Rockefeller University.

"Other [derrick barges] did not have the capacity to lift the modules," including the concrete decking, says Curt C. Zegler, construction executive for the project's construction manager, Turner Construction Co.

When it comes to modular delivery from a river, Donjon's Chesapeake 1000 had a favorable track record. The derrick had been used in another job, similar in concept, for New York Hospital in 1995, notes Zegler. For the NYH job, Chessy lifted and landed seven units to create a 485-ft-long, single-story platform.

"We used the same derrick barge—but with a different crew and different rigging—more than 20 years later," says John Witte, executive vice president of the Hillside, N.J.-based contractor. Family-owned Donjon was founded, initially as a marine salvage contractor, by his father in the 1960s.

Chessy is a boomable, stiff-leg-derrick barge, 190 ft long by 100 ft wide.

"We use water ballast to act as the crane's counterweight," says Crowe.

The boom is 231 ft from heel pin to main block sheaves and 256 ft to the 50-ton auxiliary hook. But it is the lift radius that sets Chessy apart from most land-based or marine-based cranes, says Crowe, because "she can reach out with a 1,000-ton load, 63 feet from the edge of the barge that the derrick crane sits on, and execute 600-ton lifts more than 100 feet from the barge."

The barge can get into waters as shallow as 6 ft. With its high capacity and smallish footprint, "we are in the most advantageous position to be able to get our derrick barge into just about any harbor, bay, river and canal along the East and Gulf coasts," as well as other places, crows Crowe.

After the Rockefeller University job, Chessy had been up New York state's Hudson River lifting 20 oversized units for a power plant, at a location where the closest nautical off-loading point for the units, each more than 93 ft long and 300 tons, was a shallow-water facility along the bank of Newburgh, N.Y.

In addition to Chessy, Donjon has 400-ton and 200-ton heavy-lift derrick barges and another five crane barges it uses for dredging and demolition. Donjon's fleet also includes 35 various barges for use in New York Harbor and 14 tugboats, some ocean-going.

Donjon also boasts a barge-mounted excavator dredge. “It is the second-largest excavator dredge in the U.S. to our knowledge,” says Sean Crowe, Donjon's heavy-lift project manager.

On Aug. 19, 2016, a pocket scow being used on a pier rehabilitation project at the Norfolk Naval Shipyard sunk at the face of a newly constructed pier, says Crowe. After several unsuccessful attempts at refloating, Donjon was called in.

Initial surveys verified that the barge was hard aground on a clay bottom and sitting vertically on its side shell. Donjon successfully executed a salvage plan and lifting sequence to move, roll and refloat the vessel. Then, it could be safely lifted out of the water and onto a receiving barge.

"Care was taken to keep the scow from rolling" into the new pier, which could have caused extensive damage, says Crowe.

On the morning of March 12, 2016, the tug "Specialist" sunk after colliding with a stationary construction barge while transiting under the Tappan Zee Bridge on the Hudson River. Again, Donjon was called in.

Initial surveys by a dive team indicated that the tug was sitting upright on the river bottom, in 40 ft of water, between the bridge's main-span abutments. This positioning allowed for lifting slings to be rigged on both the bow and stern of the tug, says Crowe.

The authorities approved Donjon's refloating-salvage plan, which called for bringing Donjon's "Delaware Bay" crane barge on site to serve as the salvage platform for both prep work and rigging before Chessy arrived.

To avoid high-current conditions, the salvage and dive team used slack water periods to place slings around the tug. Chessy was stationed on location by securing it alongside the prepositioned Delaware Bay. On the evening prior to the lift, divers connected the slings so that the tug would be ready to lift at first light.

On March 24, Chessy raised the tug to the surface. Throughout the subsequent investigation by authorities, the salvage team remained onboard, continuing to pump tanks to remove both weight and pollutants. Upon completion of the investigation, Chessy lifted the tug out of the river and placed it on a transport barge. 

Chessy is currently in dry dock, getting her required U.S. Coast Guard & Marine Society inspections from the American Bureau of Shipping. Donjon does this every two to three years to keep an International Load Line Certificate as well as a U.S. Coast Guard Certificate of Inspection, says Crowe. The certifications are not required for the derrick to work, but Donjon chooses to keep them to enable it to respond to any port outside of Chessy's home port of New York Harbor. It also allows operations on the open ocean.

Next up for Chessy is some upgrade work. Donjon plans to replace all the derrick's wires. That adds up to more than 4.2 miles of wire, says Crowe.