Human error is inevitable and will have severe consequences

This letter is in response to the article “Enbridge: spills are not inevitable” (Sentinel, June 10), and in particular the interview sections with Paul Stanway, Manager of Northern Gateway Communications and Ray Doering, Manager of Engineering.

Dear sir,

This letter is in response to the article “Enbridge: spills are not inevitable” (Sentinel, June 10), and in particular the interview sections with Paul Stanway, Manager of Northern Gateway Communications and Ray Doering, Manager of Engineering.

Mr. Doering cites a report written for Enbridge, which concludes that “the chance of a spill on the scale of Exxon Valdez was one in 15,000 years”.

This statement is by no means an indication that spills will not occur. A 1999 report prepared for the Canadian Coast Guard assumes a direct correlation between spill frequency and amount of oil moved by vessel; for example, twice the oil traffic results in twice the number of spills.

(This is the same approach used by the US government’s Minerals Management Service).

It is therefore safe to assume that a project of this magnitude, simply by its existence, will increase the frequency of oil spills.

The Coast Guard report states that 85 per cent of spills involve less than 7,950 litres (50 barrels) and that the probability of what is termed a “very large spill” (exceeding 1,590,077 litres or 10,000 barrels) is one in seven years in Canada.

These spills can have serious environmental consequences. Recent scenarios submitted by Enbridge show that 2.5 km of the shoreline along Kitamaat Village would be impacted by a spill of 250 m3 near the terminal.

Current technology and practices are not capable of containing a condensate spill whether in marine or freshwater and diluted bitumen spills will only be partially contained at best.

In the marine environment, particularly along BC’s North Coast, high wind and wave action are common and will make the containment and cleanup even less effective.

Along land, the remote location of the pipelines in the Kitimat valley and other river valleys in the Skeena system, when combined with weather (snow, rain, low ceilings, fog, etc.) will make it very difficult to respond to pipeline ruptures let alone contain spills, regardless of their size.

Releases into streams and rivers can have toxic effects on early life stages of fish, and can be deposited in different manners, depending upon both the time of year and the weather.

Mr. Doering’s comments raise the fundamental question of what design specifications and engineering standards will be necessary to make sure the pipeline is safe. It is easy to say that “… the risk is addressed and eliminated” but risk, as any engineer knows, is impossible to eliminate entirely.

Enbridge’s own yearly Corporate Social Responsibility reports reveal that Enbridge pipeline spills occur for any number of reasons, including: human error, pump failure, gasket failure, pipeline failure, seam failure, over-pressure on pipes, corrosion, or rocks.

To manufacture and operate a pipeline to the lowest risk possible is an extremely onerous endeavor.

For example, the need for the pipelines and terminal to be able to withstand a high magnitude seismic event is particularly important.

Can Enbridge really engineer the system to avoid ruptures during such events? If so, the Canadian public needs to know the design standards and engineering specifications Enbridge intends to use ahead of time in order to make a responsible decision, and to know whether they can make sure the pipeline is “safe”.

At this point, the Northern Gateway Application package submitted by Enbridge, and available for public viewing, lacks the information necessary to assess adequately the risks and the potential for impacts and effects.

In the June 10 article, Mr. Doering mentions only the natural hazards as “..the area that you really need to focus on”.

Of equal importance, however, are the pipeline products themselves. In particular, the pipeline carrying diluted bitumen and synthetic oil (operating in batched flow) contains products, which are higher in sulphur, metals and solids than conventional crude oil.

While the natural hazards Mr. Doering mentions are indeed of great concern to pipeline integrity, internal pipeline corrosion also occurs.

A March 2006 oil spill of 5,051 barrels (803,460 litres) at Prudhoe Bay, Alaska was confirmed by the Alaska Department of Environmental Conservation to have been caused by internal corrosion.

An inspection of this pipeline two years before the spill had revealed severe internal corrosion.

Experience transporting the more corrosive diluted bitumen is limited but it will likely require more careful and frequent inspection and maintenance of pipelines, storage tanks and ship cargo holds to avoid serious mishaps.

The Northern Gateway application does not address any of this.

Mr. Doering also states that, “..there had not been a pipeline rupture.. on any pipeline built in the last 35 years in Canada”. Ruptures in pipelines of any age speak to the inherent risks of operating and maintaining a pipeline system.

Ruptures in older systems, however, can be indicative of a company’s inappropriate maintenance and inspection protocols; the concern therefore is that inspection or maintenance problems may well continue in newer pipeline systems.


Northern Gateway pipelines, should they be built, eventually will become an “older system” and a rupture in the future is clearly as unacceptable as a rupture at any time.

The Transportation Safety Board of Canada’s Pipeline Investigation Report #P01 H0004, released after an Enbridge crude oil pipeline rupture near Hardisty, Alberta in 2001, revealed that approximately 3,800,000 litres (23,901 barrels) of crude oil was released. This was an older pipeline (constructed in 1967).

However, the report reveals that in the first 12 years of operation, it experienced five ruptures due to manufacturing defects.

After 22 years in operation, there was a rupture due to corrosion fatigue. At 23 years in operation, a leak was found due to sulphide stress cracking.

At 33 years in operation, there was one rupture due to external corrosion and a second rupture in the same year due to fatigue cracking.

Even though many pipelines with recent leaks or ruptures are older, this demonstrates that leaks and ruptures occurred when the pipeline was much younger.

Even if Enbridge operated and maintained its pipelines according to company and nationally-set standards, spills still occurred.

The company must demonstrate how the standards and practices, upon which it intends to build and operate the proposed pipelines, have improved.

And they must demonstrate how their operations, maintenance and inspection practices compare to other standards and practices globally before any new project should be considered.

As an example, the pipelines as proposed in Enbridge’s Northern Gateway application have no internal coating despite the corrosive nature of the product. How is this considered risk-free and to the highest standards?

Between 2006 and 2011, the US Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) data for Enbridge indicated that 6,136,739 Iitres (38,600 barrels) of hazardous liquid was spilled (hazardous liquid includes crude oil, diluted bitumen, condensate and synthetic oil).

The total number of reported spills by Enbridge during this time period was over 300.

Mr. Stanway seemed to play down the recent Enbridge spill in Alberta since it was due to human error.

However, we know that human error applies to all aspects of the project (indeed of any engineering project), including construction of the pipeline itself, preparation of the pipeline bed, laying of the pipeline, welding of the pipeline seams and sections, construction and assembly of valves and related piping, construction of storage tanks and related piping, and so forth.

Much of this work will occur under difficult weather conditions in remote locations.

Operation and maintenance of the pipeline will also be subject to human error throughout the life of the project.

The likelihood of the human error at some point is inevitable. It is only a question of how serious the resulting impact will be.

Since the technology to contain or clean up a spill is inadequate, we think there is a high probability of serious consequences.

Gerald Amos,


Enbridge Working Group,

Haisla Nation Council.