The Ontario Energy Board recently granted permission to Union Gas to
proceed with construction of further pipeline facilities along the
Dawn-Trafalgar corridor - an area stretching from near Sarnia to
For landowners in the corridor, this decision may cause apprehension
and concern. During the course of hearings in London and Toronto, the
Board heard evidence of landowners and expert witnesses appearing on their
behalf with respect to the impact of pipeline construction on agricultural
soils, woodlands and wetlands.
Simply put, the process of excavating the trench to lay a pipeline
inevitably causes a mixing of stone and clay subsoils with topsoil. This
mixing of sub and top soils decreases productivity of topsoil. Although
increased use of fertilizer may alleviate this loss of productivity to
some extent, it will take hundreds or thousands of years for the subsoils
to be leached from the topsoil to restore the topsoil to its original
In addition, when soils are returned to the trench after the pipeline
has been installed, difficulties in compacting the soils to their original
levels may cause subsequent erosion. Finally, the heat that is generated
by the pipeline prevents natural frost fissuring in the soils and may
contribute to drainage problems.
Problems aggravated with the mixing of topsoil and clay subsoils are
aggravated if construction is permitted to proceed during wet weather.
Evidence presented at the hearing established that, if construction
vehicles are permitted to work in weather in which a farmer would not work
his fields, there is a real danger that delicate layers of topsoil will
become intermixed with clay, creating a soil condition that is virtually
impossible to remedy.
A number of landowners represented at the hearings requested that the
Board make provision for the appointment of an independent inspector who
would have control over construction procedures, including the power to
shut down construction in wet weather. The Board has directed an
independent environmental inspector be appointed to monitor construction.
However, while acknowledging the validity of the concerns of the
landowners, the Board was not prepared to infringe on Union Gas' sole
authority to determine when weather may justify the termination of
In explaining its decision, the Board stated:
"The board concurs with board staff that specific conditions
related to individual Landowners are matters better left to private
negotiations, rather than imposed as conditions of approval. The board
notes specific conditions could result in significant costs to Union
Gas and have financial impact on the landowners. In the board's
opinion, such conditions might be better considered during
negotiations which can deal concurrently with unique construction
techniques, mitigation measures and compensation
Landowners concerned about potential impact of construction on their
lands should take note of the Board's direction. Union Gas has undertaken
to the Board to discuss with each landowner the landowner's preferred
topsoil stripping requirements. The Board did hear evidence that mixing of
subsoils with topsoils and erosion might be reduced if topsoil and
different layers of subsoils were removed and stored separately and if
soils were restored to their original strata and compaction levels.
Particularly in view of the limitation of the powers granted to the
independent environmental inspector, such landowners should include in
their negotiations with Union Gas consideration of site-specific
construction methods and techniques to attempt to limit long-term damage
to their lands.