Gazprom Neft Shelf, the Gazprom subsidiary behind the Prirazlomnaya oil platform, rejected claims by environmental groups that the rig poses a threat to the Arctic environment.
Hitting back at allegations its operations in the Pechora Sea would endanger the area, Gazprom Neft released a statement listing the measures it had taken to ensure safety at the rig, the first to be deployed to any Arctic oil field.
But it neither confirmed nor denied reports that its oil spill response plan had expired, which would make any drilling work illegal until it is renewed.
"Last winter demonstrated the platform['s] safety and reliability in the Arctic environment," the company said Thursday in an e-mail.
"A professional emergency response crew works night and day. Crews of the offshore ice-resistant stationary platform and support vessels were trained under a dedicated program for emergency response and first aid in case of sea accidents," the e-mail stated.
The company also said that observations by the Greenpeace vessel Arctic Sunrise, which visited the area last week but did not take sample from the sea, proved there was no pollution around the rig.
The company confirmed that although the rig is constantly attended by at least one support vessel carrying oil spill response equipment, at least some of the specialist response vessels needed to deal with an oil spill or other emergency will be based in Murmansk, at least three days' sailing away on the other side of the Barents Sea.
It also said it had agreed with LUKoil to cooperate in the event of a spill at its nearby Varandey oil terminal, where tankers handle oil from the Yuzhno-Khylchuyuskoye field.
The Prirazlomnaya rig, built by the Sevmash shipyards partly around the superstructure of a retired British platform from the North Sea, is the world's first ice-resistant oil rig. It was towed into position in the Pechora Sea last summer.
It has been fiercely criticized by environmentalists, who say that there is no technology available to clean up an oil spill in icy conditions and that Gazprom has been opaque about its contingency plans for spills, giving few details in a summary of the plan on its website.
Greenpeace on Tuesday published a letter from the Emergency Situations Ministry that the environmental group said proved that Gazprom's official oil spill response plan for the platform expired last month.
In a written response to a Greenpeace inquiry, the ministry said that under Russian law oil spill response plans are valid for five years. Gazprom Neft Shelf's environmental protection plan for the Prirazlomnaya platform was submitted in 2007.
"Subsequently, a letter was sent by Russia's Emergency Situations Ministry in March to Gazprom Neft Shelf with an indication of the need for processing of the oil spill mitigation plan and subsequent submission of a revised plan to relevant executive authorities and Russia's Emergency Situations Ministry for consideration and a decision on endorsement.
"However, to date, Gazprom Neft Shelf has not submitted its revised oil spill mitigation plan," the letter continued.
Earlier, Gazprom said it wanted to start drilling the first wells this summer, but although Gazprom Neft Shelf said preparation of facilities for drilling of the first production well is "currently in progress," it did not clarify when drilling is actually due to start.