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. TransCanada spokesperson Cecily Dobson says that the project is seen as an innovative and economic 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 says that this represents 83 per cent of the system’s commercial design.

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.

HDD: protecting the environment

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

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.

The commission said TransCanada had to use HDD to bury the pipe in some locations, including parts of Pembina and Sargent counties. The technique will avoid the need to cut down trees in the Tetrault Woods state forest, and a Sheyenne River Valley scenic area in North Dakota's south-eastern corner.

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

Sections of pipe were then hooked to the drill head and pulled on rollers through the hole, under the river, to the other side a distance of 1,051 metres. 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.” 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 project's length means that it is being overseen by various provincial, state and federal regulators in both Canada and the United States.

Ms Dobson says 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,” says 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 says.

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,” says Ms Dobson.

Ms Dobson says that the first task of the converting of the natural gas pipeline to oil service was to isolate the natural gas pipeline from the other pipeline to 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.

Once the pipeline has been 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. Overcoming challenges

In addition to the challenge of the HDD crossing, Ms Dobson said the weather was also a factor to be overcome. 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 into the year and postpone clean up until 2009.