Built in 2007, The initial construction of the tug originally began at SENESCO Shipbuilding of North Kingston, Rhode Island in August 2004 (hull #318) as the Freeport for U.S. Shipping Partners of Edison, New Jersey.
SENESCO Shipbuilding signed a fixed price contract reportedly in the $40 million range for the tug and barge with U.S. Shipping. The ATB was to have been delivered in 2006. The tug was to be the first self propelled vessel built at SENESCO.
The project to begin unraveling and eventually, SENESCO Marine breached it's contractual obligations, according to U.S. Shipping, which led to substantial delays and cost overruns. U.S. Shipping then took over management of the project, which was finished at several shipyards. Estimates of the total cost of the ATB Freeport were approximately $91 million.
Blount Boats in Warren, Rhode Island, built the pilothouse and tower to the point that the structures were blasted and primed. The sections were hauled by barge to SENESCO where they were mounted on the tug's hull.
Around that time, U.S. Shipping Partners took over and launched the tug where she was then moved to Portsmouth, Rhode Island, for the final outfitting. U.S. Shipping Partners rented space and set up portable generators to allow the workers to have power and lights to work at night.
The tug is fitted with an INTERcon coupler system and is powered by a pair of Wartsila 9L32 Medium Speed Diesel engines rated at 6,150 horsepower each at 750 rpm with Wartsila Gear (SCV85-P51) and a Vertical Offset Ratio of 2.4:1 turning two four bladed, 12 SSSq Wärtsilä Lips propellers mounted inside kort nozzles for a rated 12,000 horsepower. .She is capable of operating on heavy fuel oil as well as No. 2 marine diesel fuel oil. To operate the tug while on heavy fuel oil, a thermal oil heating system has been installed with heavy fuel oil pumps and thermal oil piping all provided by S-Man/American United Marine.
The Freeport is married to the 521(ft) 04(in) 156,000 bbl. double hulled barge the Chemical Transporter . Her construction was also begun at SENESCO. However, she was moved from SENESCO to Sparrows Point Shipyard in Baltimore, Maryland where it was finished.