Chevron Canada has been unable to find the source of oil seepage into Burrard Inlet that has resulted in a small marina-like sheen on the water, a spokesman said Thursday.
Ray Lord said the seepage of hydrocarbons — crude oil, gasoline or diesel —doesn’t present a danger to the public.
“We have seen a sheen from time to time at high tide,” Lord said. “It’s similar to what you might see at a marina. It’s a sheen. There’s not oil on the water at all.”
B.C.’s Ministry of the Environment estimates the size of the leakage at 50 litres.
Lord said the source of the seepage is a mystery, but suspects it is a historic accumulation as the refinery has been in production since the mid-50s.
He said underground pipes are being tested for failure and noted the area is close to settling ponds.
Down at shore, crews are using soaker pads for spot cleanup and have isolated the area with containment and soaker booms over a 20-metre intertidal area. No sheen has been observed outside the boom.
“There’s almost not enough to clean up, but we have a crew down there and we’re doing our best to address it, should we see it.”
Lord said evidence of oil began appearing in perimeter monitoring wells on the refinery property in 2009.
Last month, a routine tour of the site discovered oil, mixed with water, in a railway ditch downhill from the refinery.
Chevron said the oil was carried through groundwater. They have since seen small amounts of it on the shore of Burrard Inlet.
“This is not a leak, not a spill,” Lord said. “It’s material that has been picked up from our property and has been moved off site through the normal movement of groundwater.”
Lord said the refinery immediately began pumping the material from its monitoring wells and dug a trench to intercept groundwater by the railway tracks. The recovered oil was pumped back to the refinery for processing.