Going green takes root

New way of constructing pipelines finds favour here

A new way of laying pipelines is taking hold in Alberta.

Pipeline construction, as anyone who has travelled this province knows, is big business. But are you aware that contractors lay between 12,000 and 15,000 km of pipeline in Alberta each year?
About 85 per cent of that is pipe less than 12 inches in diameter-in fact, most pipe has a diameter less than six inches. Yet, virtually every installation requires excavating a trench between 32 and 42 inches wide.

There have been good reasons for digging large trenches. For one, buckets smaller than 32 inches have tended to clog with earth. That makes them woefully inefficient, not to mention uneconomical. Wide trenches work. They have been the industry standard for decades.

But conventional construction practices have led to environmental and economical problems. Valuable topsoil is lost forever to erosion or contaminated with subsoil. Landowners temporarily lose the use of agricultural land. Winter construction practices result in expensive spring cleanup operations, and problems can occur a decade or more after construction.

The issues related to pipeline construction haven't gone unnoticed. Working within an Alberta Environment initiative called Partners in Resource Excellence (PIRE), the government, the contracting industry, and the upstream oil and gas community have developed a process called Innovative Pipelining Strategies, or IPS. It's a new way of constructing pipelines that's cheaper, more effective, and yes, environmentally friendly.

IPS takes an outcome-based approach to pipelining. It focuses on making the smallest impact possible on the environment. In the oilsands-rich region of Wood Buffalo, where multiple pipelines may be installed in one trench and the area is forest and wetland, minimal impact might mean using a barge to float pipe over wet areas rather than damaging the land with heavy vehicles and reducing the trench line from 50 m to 35 or 40, depending on land conditions.

"In forested areas, each metre you don't have to use for the temporary storage of stripped and excavated soils as a result of minimizing excavated trench width is another metre of trees you don't have to cut down," explains Marc LaBerge, facilities construction leader at Devon in Calgary. Devon participates in PIRE.

On agricultural land, the impact can be reduced much further. About 90 per cent of the pipelines that Devon installs are between three to six inches in diameter. Conventional pipelining practices resulted in three- and even four-foot trenches. With IPS, trench width can be reduced to a mere 11 inches in some circumstances.

TOOLS TO HELP

There is a wide array of tools and techniques contractors can use to construct pipelines using IPS, some of which have been in use for several years. The Kendal Tapered Wheel, for example, was developed by a contractor in Grande Prairie with the objective of compacting the trench line to completely return the excavated soils during winter construction. This initial innovation inspired the IPS process that exists today.

Other tools and techniques were developed as a result of the partnership.

"In discussions with the contractors, they indicated that if the tools were available, the outcomes could be achieved," says Doug Kulba, program coordinator of Partners in Resource Excellence, Alberta Environment. "We quickly recognized that specialty tools and techniques would need to be developed."

Tools like narrow stripping and excavating buckets, narrow chain and wheel ditchers, and soil compaction equipment are all elements of this new way of pipelining. But practicing IPS also requires the contractor and operators to approach projects in a new way.

"This isn't about criticizing past practices," Kulba says. "Everyone was using the best available technologies at the time. This is about asking if we can do better."

Contractors need to work with the clients to assess the entire pipeline and determine the best construction strategies to minimize land impact and long-term land liabilities. Trenches are planned to be as small as possible, and other steps, such as using lighter equipment to make less of an impact on the earth, are practiced. Rather than stripping topsoil to form a place to pile removed subsoil, a practice that can impair the quality of the topsoil, material such as snow or straw is simply spread over the topsoil to form a buffer.

To prevent future problems such as sunken ditch lines, to reduce spring clean up costs, and to protect the soil from erosion and contamination, the soil is replaced as soon as possible, even during winter construction. Soil is compacted from the safe zone-a buffer of soil above the pipe-upwards, allowing the contractor to maximize the replacement of the excavated soil back into the trench.

Devon strives to return the soil capability immediately after construction is finished. Although there may be the odd bell-hole or dip to repair in the spring after winter construction, Devon says its spring cleanup costs have been greatly reduced. In fact, some pipeline projects require no final summer cleanup.

In May 2008, Devon mandated contractors use IPS on all its agricultural pipelining in Canada. The partners in PIRE-LaBerge, Kulba, and Randy Galbreath, president of Stratus Pipelines Ltd. in Grande Prairie-are presenting this greener method of construction to the oil and gas industry as well as provincial and federal government agencies with the goal of increasing industry awareness of the issues and the solutions.

With a shift toward greener construction coming down the pipe, contractors need to know what's expected of them.

Quite a bit, according to both Galbreath and Lyle Cazes, president of Low Impact Pipeline Systems Inc. Cazes has been developing the Low Impact Pipeline System, or LIPS, since 1995, as a method of pipelining designed to leave land in its former productive state.

NEEDED INVESTMENT

Galbreath estimates that some contractors may need to invest around $85,000 in equipment to construct according to IPS, if they're running two or three crews. Cazes adds that the training requirements are a further investment, with contractor training alone taking two to four weeks per year. Training must be done throughout the year, as summer construction differs from winter construction.

Contractors have to understand what the system is and the outcome they are trying to achieve, develop knowledge about the management of different types of soils and vegetation, and learn about new excavation processes.

IPS has reduced the amount of land Devon impacts through pipeline construction by about 30 per cent, simultaneously reducing downtime and costs for Devon and agricultural landowners. The benefits to the environment, landowners, and pipeline clients are clear.

While IPS is touted as leading to improved risk management, more social trust, a smaller carbon footprint, and increased employee satisfaction for contractors, the economic concerns for those losing cleanup work as well as future repair projects may be an issue.

"The contractor looks at it and he says, ‘If I do this, what do I get out of it?' Maybe I can do it faster. Maybe I can get more work because I'm doing something better. Right now today, that's a real bouncing ball," Cazes says.

Cazes would like to see pipeline owners share the savings they receive as a result of the new construction methods with contractors.

Whether the contracting industry is able to recoup any investment required in switching to environmentally friendly methods of excavation and construction may ultimately depend on their willingness to seize new opportunities.

"The contractors we work with have a lot of foresight and are already seeing new business opportunities with this new method," LaBerge says. "The dollars we can save on reclamation and clean up costs go directly toward building additional pipeline infrastructure. The most important element for Devon is making sure the work is done right the first time."


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