The oil spill was reported November 27, 2011 by a citizen who observed an oily sheen on the water and shoreline near the confluence of Sand Creek and South Platte River in Commerce City, north central Colorado. The oil released to Sand Creek and South Platte River was part of a plume of groundwater contamination originating at the Suncor Refinery property. The spill caused injury to natural resources, including: aquatic and riparian habitat near the down gradient of the point of discharge to Sand Creek; wetland habitat located on the defendants property; waterfowl associated with the former wetland on the defendants property; and, groundwater.