The 648-long-ship in January set sail from Portsmouth, Virginia, to the Mediterranean Sea, but was forced to spend months in Rota, Spain, waiting for Syria to turn over its stockpile of deadly chemicals.
The vessel in early July began dismantling some 600 tons of a nerve gas precursor and 20 tons of a mustard agent using a process called hydrolysis, which uses water and other reactants to neutralize and break down the chemicals. The work, which took place in international waters in the Med, wrapped up this week.
Defense Secretary Chuck Hagel even called Navy Captain Rich Dromerhauser aboard the ship to congratulate the him and the crew on completing the difficult and dangerous task, which only took 41 days -- much quicker than expected.
Syria, under the regime of Bashar Assad, agreed to give up the chemicals as part of an internationally brokered deal that prevented a U.S. military intervention in the country. More than 150,000 people have been killed in the three-year-old civil war, according to a human-rights group.
The conflict has helped fuel the rise of the Islamic militant group known as the Islamic State of Iraq and the Levant, or ISIL, the al-Qaida inspired Islamic organization that controls parts of Syria and Iraq. The organization on Tuesday circulated video showing the beheading of American journalist James Foley.
Syria blamed the delay in transferring the chemicals out of the country on the ongoing fighting within its borders.
The Cape Ray isn't actually part of the U.S. Navy fleet. The 36-year-old vessel is maintained by the Transportation Department's Maritime Administration as part of the so-called Ready Reserve Force, a fleet of almost 50 commercial ships that can be activated to support defense emergencies.
After the high-profile chemical dismantling mission, the ship is headed to Finland for the less glamorous job of dropping off the waste materials, which will be disposed of commercially.