Built in 2002, by Main Iron Works Incorporated of Houma, Louisiana (hull #413) as the O.J. Cenac for the Cenac Towing Company of Houma, Louisiana.
In 2008, the tug was acquired by Teppco Marine Services of Houma, Louisiana. Where she retained her name.
In 2009, she was acquired by Enterprise Marine Services of San Antonio, Texas. Where the tug was renamed as the O.J.
In 2015, the tug was acquired by Harley Marine Services Incorporated of Seattle, Washington. Where she was renamed as the Cooper Mountain.
Powered by three, Cummins QSK60 diesel engines. With Twin Disc MG 5321 DC reduction gears, at a ratio of 7:1. Turning three, 74(in) by 60(in), four bladed, fixed pitch, propellers. She is a triple screw tug, rated at 6,000 horsepower.
Her electrical service is provided by two, Tier III compliant, 132kW Cummins BTA5 generator sets. The tug's capacities are 102,400 gallons of fuel, 1,465 gallons of lube oil, and 20,500 gallons of water.
The towing equipment consists of an air over hydraulic, single drum, towing winch.