The leaked petroleum discovered in a pool outside the Kotaneelee gas plant three weeks ago was mainly heavy lubricating oil, according to lab test results.
Samples of the spilled liquid contained small amounts of oil mixed with larger quantities of water. At least part of that water was produced water, a byproduct of oil and gas recovery.
Additives often contained in lubricating oil can be toxic to plants and animals.
The spill was caused by a leaking valve in a building at the gas plant, according to an email from the Department of Energy, Mines and Resources. The leak was stopped on Aug. 8, a day after the spill was discovered.
Representatives from EFLO Energy Yukon, the company that owns the plant, “pumped the surface pool of liquid into drums and a large tank for secure storage” on Aug. 11, the email reads. They also used absorbent pads to remove as much residue as possible.
So far, about 5,840 litres of liquid have been pumped from the site. But the total volume spilled is hard to estimate, since “the volume that may have drained into the soil is unknown,” according to the department. The spill initially covered about 180 square metres.
A restoration plan for the site is still being finalized, and will include removal of the contaminated soil. EFLO was originally supposed to finish remediation by Sept. 18, but that deadline may be extended “given the remoteness of the location and progress made before the changing seasons,” the email reads.
The Kotaneelee spill was discovered by an Environment Yukon employee who was visiting the site on Aug. 7.
The government had inspected the surface lease at the gas plant once a year since devolution, according to information provided by Energy, Mines and Resources. That annual inspection had been scheduled for the week of Aug. 11. “There will be more frequent inspections scheduled on an as-needed basis during the clean-up,” according to the email.
Since the facility is dormant, the government doesn’t require EFLO to maintain a set schedule for monitoring the site. The department has received some monitoring reports from EFLO, as requested after the spill, but they are to be kept confidential.