Another Russian rocket stage likely to be holding highly toxic fuel is slated to splash down in environmentally sensitive waters of the Canadian Arctic on Wednesday.
Documents on the website of the European Space Agency say the Cold-War-era missile repurposed for satellites is to lift off from a Russian launching pad. It will drop its second stage into Baffin Bay, outside Canada's territorial waters, but within ocean it claims to regulate and control.
The launch vessel, a former SS-19 intercontinental ballistic missile, is powered by hydrazine -- a fuel so toxic and carcinogenic that almost every space program in the world, including Russia's, no longer uses it.
The spent rocket stage is expected to contain up to a tonne of unused hydrazine.
It is expected to fall into the North Water Polynya, one of the most productive and biodiverse areas of the Arctic and heavily used by Inuit hunters. The waters are considered so important to mammals such as walrus and whales that Inuit from Canada and Greenland seek to manage it as a protected area.
Eleven such splashdowns have taken place over the last 15 years, said Michael Byers, a professor of international law at the University of British Columbia.
Although the rocket is Russian, the launch is a commercial service paid for by the European Space Agency.
"The ESA prides itself on being the most environmentally friendly space agency in the world," said Byers.
"One of the ironies here is that the satellite is a cutting-edge climate- change monitoring satellite. It's of central importance for environmental monitoring."
Agency officials have said that unused fuel is burned up on re-entry, but studies done at launch sites in Russia suggest some fuel does reach the surface.
Previous launches have drawn wide protests. The federal government has filed diplomatic protests with Russia and the government of Nunavut has argued the launches put Inuit at needless risk.
The Inuit Circumpolar Commission has also objected in the past to possible contamination of pristine waters.
The federal government did not immediately say if it has filed a protest over the upcoming launch.
Byers points out that while Canada may have little influence over Russia, it is an associate member of the European Space Agency.
"We have, or should have, considerable influence over the ESA," he said. "I see no evidence that it was exercised."