The Keystone Pipeline project is unique compared with other projects in that it combines both the new construction of pipeline and the conversion of an existing pipeline from natural gas to oil service.

The 3,456 km Keystone Pipeline is also set to serve the interests of the United States by providing a secure and reliable supply of Canadian crude oil to meet the growing demand by US refineries and markets. Approximately 2,219 km of new pipeline is to be constructed in the United States. The Canadian portion of the project includes the construction of approximately 373 km of new pipeline and the conversion of approximately 864 km of existing TransCanada pipeline from natural gas to crude oil transmission.

TransCanada spokesperson Cecily Dobson said that the project is seen as an innovative and cost-competitive way to accommodate the expected growth in Canadian crude oil production during the next decade.

Canada is the largest importer of crude oil to America supplying 2.2 MMbbl/d. TransCanada has secured commitments for 910,000 bbl/d over an average term of 18 years for the Keystone Pipeline. Ms Dobson said that this represents 83 per cent of the system’s commercial design.

Converting to oil

Converting the existing facilities and constructing new facilities in Canada, North Dakota and northern South Dakota began in 2008, while construction of new facilities in South Dakota, Nebraska, Kansas, Missouri and Illinois will begin this year.

“It is estimated that more than 5,000 individuals will have worked on the design and construction of the Keystone project by the time it’s been completed,” said Ms Dobson.

Ms Dobson said that the first task of the conversion of the natural gas pipeline to oil sevice was to isolate the natural gas pipeline from the other pipeline from which it was interconnected. Existing natural gas in the pipeline was transferred to other natural gas pipelines using a portable transfer compressor.

According to Ms Dobson, the greatest challenge of the conversion was to separate the converted pipeline from the other gas pipelines in a safe manner while ensuring there was no impact to existing shippers. She said that the pipelines were very congested in the compressor stations, which made excavation difficult. In addition, the ground to be excavated was frozen.

The first third of the pipeline, roughly 200 km in length, has been purged of natural gas, with the remaining pipeline to be purged throughout 2009.

Once the whole pipeline is purged of natural gas, it will be ready for the removal of drip tanks and tie-over assemblies. Following the isolation of the pipeline, an in-line inspection using a pigging tool will be completed to ensure the integrity of the pipeline and that it is ready for oil service.

“The pigging and purging is done in one third increments as the smart pig can’t run through the pipeline at one time,” said Ms Dobson.

Conventional construction challenges

The project crosses several large rivers, including the Mississippi, Missouri, South Saskatchewan and Red Deer rivers, using horizontal drilling technology (HDD).

TransCanada spokesperson Terry Cunha outlined the details of one HDD drive, the Pembina River crossing, west of Walhalla. The North Dakota State Forest Service acquired 432 acres of Pembina Gorge land in 1970 that now is Tetrault Woods State Forest. In May 2006, the Forest Service started to negotiate with representatives of Keystone Pipeline and it was decided that HDD was to be used to avoid the need to cut down trees in the Tetrault Woods state forest, and a Sheyenne River Valley scenic area in North Dakota’s southeastern corner.

In Pembina County, the crossing involved setting up a drill rig on the south side of the Pembina River. A 4 – 6 inch diameter pilot hole was drilled at an inclined angle, 7 – 9 m below the surface of the ground and river.

Sections of pipe were then hooked to the drill head and pulled 1,051 m on rollers through the hole to the other side of the river. Bentonite clay was used to fill the hole around the pipeline.

The drive involved approximately 15 workers in making the hole to feed the pipe under the Pembina Gorge.

Mr Cunha said that similar to other HDD drives on the project “the challenge for the Pembina River HDD is ensuring we protect the special features and the natural beauty of the area while getting the pipe in place to deliver oil.”

In addition, the Keystone project experienced some extremely wet conditions during the 2008 construction season. In North Dakota, it was one of the wettest years recorded in history. Ms Dobson said that TransCanada was forced to extend the construction season later in the year and postpone clean up until 2009.

Stakeholder involvement at length

Not only is the Keystone Pipeline project unique in the fact that it involves the conversion of an existing pipeline, but the projects length means that it is overseen by various provincial, state and federal regulators in both Canada and the United States.

Ms Dobson said that a comprehensive stakeholder engagement program, developed and adapted to specific stakeholder needs according to the nature, location and potential effects, has been implemented.

Stakeholders include landowners and residents; community leaders; federal, provincial and local elected representatives; aboriginal and Native American stakeholders; regulatory agencies; emergency services organisations; special interest groups; and, co-located right of way owners.

“We recognise the importance of incorporating public input into our project plans,” said Ms Dobson. “We believe that through consultation we can address questions and concerns, and integrate important public input into our activities.

“We share project information and gather input throughout the planning phase and incorporate feedback into our project design and implementation as appropriate,” she said.