Husky analysis of North Saskatchewan River water quality data and map
From Husky here
Map included at bottom of item
North Saskatchewan River Water Quality Evaluation – August 2, 2016
The purpose of this communication is to present, through a question and answer format, the results of water quality testing conducted following the July 21, 2016, crude oil release into the North Saskatchewan River approximately 75 kilometers upstream of Paynton Ferry, SK. A group of technical experts was formed to prioritize scientific consideration of drinking water and agricultural uses of river water downstream of the spill in order to determine current and ongoing risks to downstream river water use. The technical group included: engineers, environmental specialists, toxicologists, and public health specialists representing the Ministry of Environment of the Province of Saskatchewan, the Saskatchewan Water Security Agency, Health Canada, Husky Energy, Matrix Solutions Inc., and the Center for Toxicology and Environmental Health, LLC (CTEH). The report is based on sampling data collected by professional third party consultants as approved by Unified Command.
What type of oil was spilled and what happens to the oil in the environment?
The oil that was spilled is a diluted crude oil called HLU Blended LLB Heavy Crude Oil (LLB Crude). It is a naturally occurring mixture of oils that is produced from oil fields near the Lloydminster area of Saskatchewan and Alberta, and refined into synthetic oils, diesel fuel, and other products. When initially spilled into a water body, LLB Crude is most likely to float on top of the water before some components of the oil begin to sink. Over time, the oil undergoes a process called weathering in which more volatile components of the oil evaporate and break down naturally in the atmosphere. Thicker, asphalt-like components in the oil are broken down more slowly over time by bacteria and other natural processes.
Why were river water intakes closed as a result of the spill?
Oil is not normally found in the river, and typical river water intakes and water treatment facilities could be compromised if contaminated by oil. It is recognized that in light of events such as this, requirements to make proactive and precautionary decisions regarding the safety of public water supplies is critical. The measures taken to isolate the downstream water supply intakes were warranted in response to the incident. Municipal authorities are to be congratulated on their proactive and decisive measures taken to date to safeguard their infrastructure and water supply.
Where did the oil go?
The spilled oil has been found on the river shoreline, in the river water column, and in river sediment mostly at locations within 20km downstream of the spill. Sheen and foams were also reported on the surface of the river farther downstream. However, to understand how far downstream the oil may have traveled is being determined through water and sediment testing as far as Prince Albert, SK, with priority sampling at river water intakes in Prince Albert and North Battleford, SK.
What water quality testing is being performed and what are the results?
Sampling teams have conducted a river sampling program that began on July 21, 2016. The program includes over 1,000 water samples collected to date (06:00 MDT, August 2, 2016) at over 60 locations along the river, extending from the release site to Prince Albert, SK, approximately 385 km downstream. These include samples collected at river surface and at different depths down to the river bottom. Responders are also assessing sheens and foams on the river potentially related to the oil. Monitoring work is ongoing. Laboratory results are complete for more than 900 of the water samples, and the primary indicators of the oil (benzene, toluene, ethyl benzene, xylenes (BTEX), total hydrocarbon fractions (F1-F4), and polycyclic aromatic hydrocarbons (PAHs)) have shown exceedances of applicable Canadian drinking water guidelines in five samples within 20 km. No additional exceedances have been detected in any samples at any location since July 24, 2016, including the water intakes at North Battleford and Prince Albert. Furthermore, no exceedances of agricultural water quality guidelines have been detected to date. Water sampling is ongoing, and recommendations regarding the risk of oil affecting river water intakes will be forthcoming as a formal water intake risk assessment is completed. The Water Security Agency has initiated an independent sampling program and will be doing more in the coming days.