The proposed Mackenzie Gas Project has been chosen to provide context to this discussion of permafrost in boreal environments and its impact on human activity. While additional information may be found by following the links in the Reading List, a brief primer regarding natural gas and this project will be given here.
Properties of Natural Gas
Natural Gas is comprosed of a number of lightweight hydrocarbons including methane, ethane, propane, butane, and pentane. However, it is primarily methane which typically makes up between 70% and 90% of the mixture. Additionally, natural gas contains trace amount of other substances as well including carbon dioxide, water, and, in the case of "sour" gas, hydrogen sulfide (Natural Gas Supply Association). (Natural gas that does not contain naturally occuring hydrogen sulfide is refered to as "sweet" natural gas.)
Because of its composition, natural gas has many important properties. For example, natural gas will remain in a gaseous state at room temperature even under very high pressures exceeding twice atmospheric pressure. As a result, natural gas is transported in gaseous form. Another important property is that natural gas is lighter than air. In other words, natural gas will float in air and rapidly disperse in it. Finally, natural gas is flammable; it will burn, or explode, readily if ignited in the presence of oxygen.
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Pipeline Route
The proposed pipeline will extend approximately 1300 km from Inuvik, NWT along the Mackenzie River into Alberta where it will hook into pre-existing pipeline system. Additionally, nearly 150 km of pipe will connect the three primary production fields to the Gathering Station in Inuvik. Of this length, approximately 500 km (650 km including the pipes from the production fields) to Norman Wells, NWT is continuous permafrost. The remaining 800 km south of Norman Wells to Alberta runs cheifly through discontinuous permafrost with only the southernmost portion running through unfrozen ground.
| The main trunk will actually consist of a pair of pipes; one will carry the "purified" natural gas while the other will carry the liquified heavier components, i.e. butane and pentane, of natural gas known as natural gas liquids. The pipeline will carry slightly more than 1Bcf of natural gas to market each day. That amount of natural gas is enough to heat the entire city of Yellowknife, NWT for an entire year (Mackenzie Gas Project). |  |
| Top of Page | The route of the
Mackenzie Gas Project pipeline. Mape courtesy of the Mackenzie Gas
Project. |
Facilities
In addition to the pipeline several other facilities will be needed to move the natural gas southward from the Mackenzie River Delta. The primary facilities include the Gathering/Compression Station in Inuvik and the Compression Station at Norman Wells.
The Gathering Station will fulfill numerous tasks. The most important of these being the dehydration of the raw natural gas, the removal of other trace gases such as carbon dioxide and hydrogen sulfide, and the seperation of the natural gas liquids. The pair of Compression Stations will, as the name suggest, pressurize the gas to 1800 psi which will facilitate its transport down the pipeline. The Compression Stations will also chill the natural gas to 0°C (Mackenzie Gas Project).
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