Mr. Locke is the equipment manager for Western Canadian Spill Services, an industry co-operative that has stationed $9-million worth of spill response gear in 36 places across B.C., Alberta and Saskatchewan. When oil leaks, especially into water, he is among the first to hear about it, because that equipment is crucial to cleaning it up.
And it’s almost always urgent. Take the recent spill in the Red Deer River from a Plains Midstream Canada pipeline. Mr. Locke got the call on a Thursday at 10 p.m. By 1 a.m., he was at the spill site, beginning the work of marshalling a response.
The first hours of a spill are crucial, and this is made even more urgent when oil leaks into a major river that is rapidly spreading it downstream.
But early efforts soon give way to a sustained attempt to scrub oil from rivers and reservoirs, back eddies and shorelines, sandbars and rocks and trees and grass. Oil spills are messy, and even more so when a flooding river deposits black stains far past its banks. Cleanup is done through a combination of tools, uniquely designed products and manual labour – the 2010 Enbridge Inc. spill in the Kalamazoo River employed 2,500 at its peak.
The results can be remarkable.
“I’ve seen situations where you look at something and say, ‘that will never get back to normal.’ And you go back two years later, and you’d never know there was a spill there,” Mr. Locke said. “The technologies have improved a lot in the last few years for cleaning up soil and cleaning up groundwater and getting it to the point where it’s as pristine as it was before.”
Yet the sheer difficulty of some spills – especially those like the 160,000 to 480,000 litres that leaked into the flooding Red Deer River – means that recovery efforts often fall far short. In some cases, much of the oil on shore is left to break down naturally.
Even on the water, where oil might be expected to float, it doesn’t always. Leave it long enough – in some cases, just a day – and it will attract sediments that weigh it down. In roiling waters, that process is accelerated to such a degree that in some waterways, a spill response is virtually useless.
“If you have a major spill on a really rough river, it’s almost a lost cause, just because there’s not a lot that can be done,” said Craig Myers, who was the on-scene co-ordinator for the U.S. Environmental Protection Agency response to the ExxonMobil spill into the Yellowstone River last July, a leak that has much in common with the Red Deer River incident.
Still, responders call on a tremendous toolkit. In a river spill, they scramble to get ahead of the slick, angling booms across the waterway to squeegee oil from the surface. That oil is collected at shore, where it is either vacuumed or skimmed off. Booms are placed around sensitive spots, like protected areas or water intakes, to keep oil out. Absorbent pads that soak up oil but not water can be employed to grab any sheen that makes it past the booms. Colourful tape, fencing and owl effigies are used to scare away wildlife, and teams of experts brought in to make sure animals are kept safe.
If the oil gathers in slacker water, such as the Gleniffer reservoir, where it has collected from the Red Deer spill, booms can be used to corral it and tow it to shore for cleanup. Barge-mounted skimmers can be used on the open reservoir.
The river itself is trickier. Helicopters, airboats and jetboats are used to find pockets of oil floating in back eddies, where it can either be sucked up by boat or grabbed from shore by vacuum trucks, whose 100-metre hoses can reach a good distance away from roads.
The shoreline is even more difficult. Pressure washers can be used to spray off gravel. But oil clumps in tall grasses. It stains tree trunks. It leaves a sheen on mud. To clean that up, there are two options: removal, or no action. Removing it can be arduous. In some places, it can be picked up with backhoes and Bobcats. Elsewhere, it’s a matter of hiring large crews of workers with shovels and rakes to dig out the sullied soil and vegetation.
In many cases, it’s less disruptive to leave it alone. Sometimes, natural decay processes can be aided: workers can spray nutrients that speed the work of microbes that break down the oil.
River spills, however, are among the hardest spill responders have to face. The oil is mobile, and most equipment – skimmers and the like – is designed for calm water. So spill responders tend to view their work with some humility. Although oil and pipeline companies often promise a full cleanup after a spill, the reality is “that virtually never happens,” Mr. Myers said.
“It is very hard to get every drop that was spilled, just because it weathers. It degrades in the sun. It sinks. Some of it just gets away.”
Original Article
Source: the globe and mail
Author: Nathan VanderKlippe
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