Water Quality Sampling on North Saskatchewan River - Update July 20, 2017
July 20, 2017 - The Water Security Agency (WSA) released the latest verification results for monitoring of surface water, river sediments and the North Battleford surface water treatment plant sediment collection tank.
WSA continues to monitor surface water and sediments from the North Saskatchewan River in relation to the Husky Energy oil spill of July 2016. This independent sampling is being conducted to verify water and sediment quality results reported by Husky. Surface water and sediment quality is being monitored at four key sites: North Sask River at: #3 Hwy crossing (located upstream of the spill point), #21 Hwy crossing, North Battleford opposite WTP intake and Prince Albert opposite WTP intake.
WSA’s water quality sampling found no detectable levels of Petroleum Hydrocarbon (PHC) compound on June 23, 2017. Samples for Polycyclic Aromatic Hydrocarbons (PAH) were collected however results are pending.
WSA’s sediment quality monitoring detected trace levels of petroleum contaminates at all key sites, including upstream of the spill point. This includes trace levels of Benzene, Ethylbenzene, Toluene and m+p Xylene and the F3 PHC fraction at trace levels. However, none of the values detected exceeded the sediment quality guidelines for protection of aquatic life. Of the detected hydrocarbons (F3 PHC) it is likely that only the presence of F3 hydrocarbons at two monitoring sites opposite North Battleford could be related to the Husky Energy oil spill or other sources. Further results for PAH compounds may allow us to discern the source of the detected F3 hydrocarbons.
Monitoring of the sediment settling chamber tanks at the North Battleford surface water treatment plant was performed to determine what hydrocarbons may be present in suspended sediments transported along the river during winter month and released during spring runoff and in late June during higher flows from mountain runoff.
Monitoring results from the chamber tanks indicated the presence of a number of PHC and PAH related compounds associated with the suspended sediments at trace levels, including three exceedances of the sediment quality guidelines for protection of aquatic life, although those guidelines are typically applied to river bottom sediments. The presence of trace amounts of contaminants, notably the PAHs, is expected in river sediments since there are both natural and human derived compounds in this group. The results of treated drinking water quality monitoring for North Battleford showed that these sediments were removed and that North Battleford’s treated drinking water was free of petroleum hydrocarbon related contaminants.