ABERDEEN, Md. — At the end of January, chemists and engineers left Aberdeen Proving Ground for the Mediterranean Sea to lead the historic destruction of Syria's chemical weapons.
More than two months later, they're still waiting for the mission to start.
As the Syrian conflict lurches into a fifth bloody year, the forces of President Bashar Assad appear to have gained the advantage over U.S.-backed rebels. Assad's army, once dismissed as inadequately equipped, ill-prepared for guerrilla fighting and of suspect loyalty, has capitalized on infighting among the rebels and a steady flow of support from Moscow and Tehran to chalk up victory after victory.
Meanwhile, the agreed-upon destruction of Syria's chemical weapons — a rare positive development for the rebels and their Western backers — has been beset by delays.
After hundreds of civilians reportedly were killed in a chemical attack on a Damascus suburb last summer, Assad said he would surrender Syria's weapons stocks to be destroyed by an international team.
But amid fighting that has left more than 100,000 dead and displaced a quarter of the population, the regime has missed several deadlines to complete the delivery of the chemicals, putting the mission weeks behind schedule.
The Marylanders won't begin their shipboard operation to neutralize the most dangerous materials until they have the entire stockpile. With only about 40 percent of those chemicals now under international control, the head of the Organisation for the Prohibition of Chemical Weapons acknowledged recently that the June 30 deadline for their complete destruction could be in jeopardy.
The mission has been complicated further by tensions between its two principal architects — the United States and Russia — over Moscow's annexation of Crimea. Plans for a joint NATO-Russian operation to provide security for the U.S. container ship on which the Aberdeen team is to destroy the chemicals have been canceled.
In the meantime, some 64 civilian specialists from the Edgewood Area of Aberdeen Proving Ground — some of them now aboard the container ship MV Cape Ray at a naval station in Rota, Spain, others still in Maryland, awaiting orders — remain in limbo.
"The crews are ready. People are champing at the bit to go," said Jeffrey Harris, a civilian leader with the Pentagon's Joint Program Executive Office for Chemical and Biological Defense in Edgewood. "We're just waiting for Syria to hold up their end of the bargain."
Syrian officials agreed last year to transport chemicals from 12 sites to the Syrian port of Latakia, where they are being loaded onto cargo ships provided by Denmark and Norway. They have blamed delays in delivering the chemicals on security problems.
The Edgewood team, a mix of Army civilians and contractors associated with the Joint Program Executive Office and the Edgewood Chemical Biological Center, is waiting to destroy Syrian stocks of the World War I blister agent mustard and the sarin precursor DF.
When the Danish ship Ark Futura has received all of Syria's declared stocks of those chemicals — some 566 tons — it is to sail under heavy security to the Italian port of Gioia Tauro. There the materials are to be transferred to the Cape Ray.
The Marylanders are then to head out to international waters, where members are to neutralize the chemicals on equipment they developed in Maryland for the mission. The waste is to be taken to Germany and the United Kingdom for disposal.
The Edgewood specialists have decades of experience in destroying U.S. and other weapons stocks — but at highly secure and often remote facilities, on land, built for the purpose. Now, for the first time, they're planning to do the work aboard ship, on the open sea.
Leaders say safety, not speed, will be their priority. The work is expected to take between 60 and 120 days.
Ahmet Uzumcu, head of the Organisation for the Prohibition of Chemical Weapons, expressed optimism last month that the mission still could be completed on schedule.
"I think that some targets have not been met," he told reporters after meeting with Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov at the Hague. "But the deadline of 30 June still remains our target, and we think we can finish the destruction by that time, or close to that time."
Kerry said "real challenges" lie ahead.
"We in the United States are convinced that if Syria wanted to they could move faster," he said.
U.N. Secretary-General Ban Ki-moon has urged haste.
"The precarious and unstable nature of the security situation further underlines the importance of expediting the removal of chemical weapons material from the Syrian Arab Republic as quickly and as safely as possible," Ban wrote last month in a letter to the U.N. Security Council obtained by the Associated Press.
Even among Western allies, the mission has aroused controversy. Originally, the materials were to be destroyed in Albania, but a public outcry there led the government to rescind its offer. No other country volunteered to host the operation, and the Organisation for the Prohibition of Chemical Weapons made the decision to destroy the materials at sea.
Still, Greece and Turkey have raised concerns, as have some officials in Italy.
The United States and others blame Assad for the Aug. 21 sarin attack that reportedly killed hundreds of civilians in the Damascus suburb of Ghouta. Assad has denied the accusation.
Under the threat of a U.S. military strike, Assad acknowledged maintaining a chemical arsenal and agreed to turn the stocks over to the international community.
By then, the Edgewood team had developed a deployable system for destroying the weapons. Pentagon leaders had seen a need for such a system in December 2012, after the first reports that Syria had used chemical weapons on opposition fighters, and gave the Edgewood specialists six months to get one ready.
The team expedited the project, delivering within months a system that ordinarily would have taken years to develop. The new Field Deployable Hydrolysis System was based on the technology used to destroy the U.S. stock of mustard agent at Aberdeen Proving Ground under the Chemical Weapons Convention of 1997.
Using the hydrolysis system, team members do not handle the materials directly. The chemicals are mixed in a closed container, and the resulting effluent is to be discharged into closed containers. Members are to wear masks with air hoses.
The team is expecting 540 tons of DF and 26 tons of mustard. The materials both are neutralized in the same way: They are mixed with water.
The resulting effluent is acidic. Team members plan to add chemicals to bring the pH level above neutral, creating a caustic liquid that some have likened to Drano. In that form, they say, it will be safer to store and transport to its eventual disposal site.
Harris stressed the experience of the specialists involved.
"Most of these people going have been doing this for 15, 20, maybe as long as 30 years," Harris said. He said the chemistry "has already been proven out in other elimination operations."
"We've done large-scale hydrolysis of both DF and mustard here in the United States," he said. "So we're using our experience, the procedures there, the lessons learned, and applying that to this mission as well."
For now, however, they wait. Since February, Harris said, teams of about a dozen have been rotating onto the Cape Ray for three weeks at a time to test the equipment and firm up procedures and plans.
Others remain back at Edgewood, where they are working on other projects while waiting for the call to deploy.
"You can imagine just the constant delays have put people's personal lives on hold," Harris said. "They can't really plan anything because they're waiting for this mission to occur."
Los Angeles Times reporter Patrick J. McDonnell and Reuters contributed to this article.