After a U.S. strike on Syria was narrowly avoided this past September, Syria agreed to give up its entire chemical weapons stockpile. While a diplomatic success, the agreement still posed several logistical issues, the most pressing of which was who would destroy the chemical weapons. Left with little option, the United States has agreed to destroy the weapons itself at sea.
The Nobel Peace Prize-winning Organization for the Prohibition of Chemical Weapons had set a December 31st deadline for the disposal of the most dangerous of the weapons, which Syria has roughly 100 tons of. The United States has agreed to meet the Syrian army at a Syrian port, and take the weapons to the middle of the Mediterranean, where a refurbished Navy ship will destroy the weapons based on as-of-yet unused Pentagon technology.
This still leaves the dangerous transportation of the weapons to the Syrian army, which makes the weapons an even greater target for rebel attack. While the Syrian army guards the weapons at secure facilities now, the journey from the facilities to the ports will follow the dangerous Homs-Damascus road. Without any outside force offering security to the weapons, the hardest part might not even be destroying them, but getting them out of Syria.
Another issue is what will the United States do with the effluent after destroying the chemical weapons. While the chemicals will no longer be weapons, the United States has not yet revealed what it will do with the tremendous amount of chemical waste. Historically, it dumped chemical weapons just five miles off of the United States coast. Hopefully, history will not repeat itself.