Latest spill deemed non-hazardous
Outfall No. 3 the site of three spills within 10 months
Saturday, Jul 19, 2014 06:00 am
A city investigation suggests that the mysterious grey foul-smelling substance found at Outfall No. 3 this week was not hazardous, and may even be a natural occurrence.
An unidentified blue-grey substance showed up in the pond outside the stormwater outlet by the Riel BMX park earlier this week. It was the third time that a substance of this sort had appeared at this location within the last 10 months.
Crews contained the fluid with booms and tested it before it could reach the Sturgeon River, said Jeff Yanew, city environmental co-ordinator.
“The substance appears to have a black hue to the water,” he said in an email, and produced a strong septic odour when stirred up.
While the substance looked very similar to the stuff that showed up back in September 2013, lab tests show that its contents were very different, Yanew said. There were no heavy metals this time, for example, and no fecal coliforms. All potential hazards in the water were at concentrations below limits set for sanitary sewage and the protection of aquatic life.
Crews sucked up about 50,000 litres of fluid from the pond and, as it was non-hazardous, dumped it into a nearby sanitary sewer line for treatment at the regional wastewater treatment plant near Fort Saskatchewan.
The city currently has no leads as to the nature or source of this substance, Yanew said.
“We have no evidence to suggest this is an illegal dump, but I can say this looks to be the same stuff from last year.”
Yanew theorized that the substance might be naturally occurring – possibly the result of heat and stagnant water.
This outfall didn’t have a pool outside of it before, he explained. Heat combined with low flows and sediment collecting at the bottom of the pool could be creating septic conditions, triggering the growth of this substance.
“This is just speculation,” he emphasized, adding that he will continue to investigate.
Mysterious grey substances last showed up at this outfall in October and September.
The September substance was found to contain high levels of aluminum, iron, chromium and zinc, each of which was slightly or significantly above the Canadian Council of Ministers of the Environment’s guidelines for the protection of aquatic life.
The October substance contained similar metals, but at non-hazardous levels. Using a camera, city crews traced the source of that substance to somewhere on Rayborn Crescent.
Questions or information on the substance should go to strategic services director Leah Kongsrude at 780-459-1746.