There is still uncertainty about the environmental effects of a major gasoline spill in Resolute Bay, Nunavut.

Officials say an estimated 87,000 litres of gasoline poured onto the ground at the hamlet’s fuel tank farm between Oct. 27 and Oct. 28.

The Government of Nunavut hired contractor Nunami Stantec Ltd., which submitted a draft report detailing the cleanup and spill assessment at the site.

Using Access to Information legislation, the CBC has obtained a copy of the draft report the company completed Dec. 19.

'Gasoline spurting out'

According to interviews cited in the draft report, a truck driver who wanted to fill up with gasoline around midnight on Oct. 27 noticed one of the tanks at the farm was empty. He asked someone else to open a valve from a larger tank to allow the empty one to fill. Both people then left the site without turning off the valve.

The document details that at about 6:30 a.m. the following morning, a First Air employee noticed "gasoline spurting out of the vapour release valve" of the previously-empty tank.

The Government of Nunavut redacted the fuel tank logs, so it is unclear how much fuel was in the tanks both when the leak started and when it was stopped.

Some fuel contained

Two employees from Nunami assessed the site between Nov. 7 and Nov. 15.

The document shows Nunami focused on three areas: a 20,000 litre containment area around the tank which leaked, a larger lined spill catchment basin southeast of that tank, and the area immediately downhill from the leak, which includes a sensitive marine environment in Resolute Bay.

The engineers concluded that anywhere from 19,000 to 67,000 litres of the leaked gasoline was contained. A total of about 87,000 litres spilled.

Soil contamination

The engineers analyzed soil samples in an effort to figure out how and where the gasoline spread. They compared chemicals in the soil samples to chemicals found in the catchment basin.

In the draft, the engineers wrote that samples they took downhill from the spill site "showed evidence of primarily gasoline contamination," adding that those samples also show signs of diesel contamination.

Chemicals found in the soil at two areas east of the spill catchment basin – one on the opposite side of an access road – also have properties similar to gasoline. It’s unclear, though, when that soil was contaminated. The draft report notes it’s possible that it was contaminated in a previous spill.

Emails between Nunami and the Government of Nunavut also show the fuel sample taken from the catchment basin was scheduled to be tested in order to confirm it did in fact come from the tank which leaked.

"Several factors ... resulted in a level of uncertainty"

The engineers give a number of reasons for the level of uncertainty in their draft report.

They said it would have helped them to have had accurate design drawings of the site.

The document also highlights the challenges the crew had in doing their assessment, such as cold temperatures, blizzard conditions, short daylight and a limited availability of equipment.

Recommendations Redacted

The draft report includes three pages of recommendations for the Government of Nunavut.

However, those recommendations are unknown because the territorial government redacted that section of the document.

The government cited a section of the Access to Information and Protection of Privacy Act which deals with information which could be used to make future decisions.