The first flight of Russia's Soyuz medium-lift rocket from Europe's spaceport here still is pegged for the second half of 2009 but government and industry officials say privately that an early 2010 date looks more likely.

They said much will depend on the exact arrival dates of the ocean-going vessels carrying Russian-built Soyuz launch pad gear, and how well the 200-250 Russian pad construction workers, expected to begin arriving in late August, adapt to their tightly sequestered life here.

Officials from the Arianespace commercial launch consortium say that despite the delay in Soyuz operations from the Guiana Space Center — the first flight is one year late assuming the late-2009 date holds — no Soyuz customers are likely to be affected. Arianespace of Evry, France, will market the Soyuz along with the European-built Ariane 5.

"Obviously we are working as hard as possible to get Soyuz operational as quickly as we can, but the fact is that the delay can be absorbed by placing larger Soyuz payloads onto the Ariane 5 rocket, and the smaller ones on the Soyuz vehicle we use with Starsem from the Baikonur Cosmodrome," said Michel Bartolomey, director of Guiana Space Center operations for Arianespace. Starsem SA is a French-Russian joint venture led by Arianespace that markets commercial Soyuz launches from Baikonur.

The heavy-lift Ariane 5 rocket is expected to divide with Soyuz the Arianespace booked telecommunications satellites weighing 3,000 kilograms or less. Satellites much heavier than that would be directed to Ariane 5, which launches two satellites at a time. Lighter spacecraft, such as those for Europe's Galileo satellite navigation constellation and the mobile communications constellation owned by Globalstar Inc. of Milpitas, Calif., can be launched from the Russian-run Baikonur Cosmodrome in Kazakhstan, Soyuz's traditional home.

The arrival of Russian hardware and personnel to complete the Soyuz launch pad will put unprecedented stresses on local operations here and require teams of interpreters and a bolstered police force to smooth out potential rough spots, officials here said in July 20-22 interviews during a meeting of European space ministers.

The Russian teams will be sequestered some 13 kilometers from Ariane 5 operations and will be staying in nearby Sinnamary and barred from most visits to the Ariane 5 launch site in the interests of security.

Similarly, the Russian teams have declined to share the formula for Soyuz kerosene fuel, which thus will be shipped from Russia, along with individual rockets, to the launch pad here.

The Soyuz integration hall will likewise be off-limits to non-Russian personnel except on special occasions. "When we say this is a Russian operation, we mean it," Jean-Marc Astorg, head of the Soyuz in Guiana project at the French space agency, CNES, said during a July 22 briefing at the Soyuz launch site. "Non-Russian personnel will not be allowed in except under escort."

The first of three vessels containing Soyuz launch pad sections was scheduled to arrive July 27. On board is a service cabin from where launch preparation teams can work until just before launch. The first 15 Russian Soyuz construction workers were expected to be here by then as well.

A second marine vessel is scheduled to arrive in October or November, to be followed by a third ship toward the end of the year with the mobile gantry, a 60-meter-high structure that permits workers to access the Soyuz vehicle on the launch pad once it has been moved into vertical position.

The gantry's construction and delivery are months behind schedule following the financial collapse of its Moscow-area builder and the attempted seizure of the company's plant by creditors. The Russian space agency, Roskosmos, stepped in to restore order to the work flow, but gantry development is now distributed among three sites in the region, said Astorg, who visits the manufacturing teams twice a month to monitor progress.

Eighty additional Russian launch pad construction workers are scheduled to arrive in the coming four months, with the total team to reach up to 250 at its peak in mid-2009.

Local officials here say frankly they are not sure what to expect from the Russians, who will be given special cards they can use at the Sinnamary restaurant. One official said a former French Legionnaire of Russian nationality has been hired to assure that, during their free time, the Russians are provided with sports and other activities.

This official said the Sinnamary law enforcement contingent is being expanded with a new building to ensure that contact between the Russians and the local population does not create friction on Saturday nights.

Astorg said the equatorial environment at the center likely will require some adaptation by the Russian teams. "Working on a reflective rooftop in 100 degree heat and high humidity — we have trouble finding anyone who can do it other than the Brazilians," Astorg said.

While the project's delays would argue in favor of a night shift, such shifts were sharply cut back during construction of the non-Russian buildings after workers were stricken with papillonite, or lepidopterism, a skin infection caused by nocturnal butterflies.

In most people, symptoms are limited to a itching that can last for a week. But others suffer allergic reactions. Mosquitoes are another problem that make work after sundown difficult, Astorg said.

The Soyuz at the Guiana Space Center program was agreed to by the European Space Agency in 2002, with France taking a 63 percent share of the capital investment of 344 million euros. With inflation, that figure is now estimated at 400 million euros ($634 million). Arianespace is financing 121 million euros of this sum through a loan from the European Investment Bank that was guaranteed by the French government and will be repaid over a decade from launch fee revenue.