Report - Agence canadienne d'évaluation environnementale

Assessing the risks related to the project
♦ Opinion 10 — To plan emergency measures regarding the pipeline, the Panel is of
the opinion that the proponent should pay special attention to public gathering places
such as campgrounds in the impact area within the 3 kW/m 2 thermal radiation limit.
Assessing the risk associated with the pipeline
According to the proponent, the analysis performed demonstrated that estimated risks
were in compliance with the acceptability criteria established by regulatory
organizations throughout the world for oil and gas facilities, process plants,
transportation equipment and ports. Moreover, they would comply with the MIACC’s
previously specified criteria. According to these criteria, the maximum acceptable risk
level for the public is 10 -4 per annum, i.e. an occurrence every 10,000 years. Results
demonstrated that risk levels would be acceptable even for someone who would be
permanently above the buried pipeline (Figure 12). The risk would be negligible for
anyone who would be 100 m from the pipeline at all times, which means that the
return period is greater than 10 million years.
However, in the perimeter around the switching station located halfway of the
proposed pipeline, as well as at the connection points between the LNG terminal and
the TQM Pipeline, the individual risk level increases. This localized increase is related
to the frequency of leaks stemming from the presence of elements such as valves and
flanges. However, according to the analysis made, this risk would always be below
the 10 -4 per annum limit, and as such was deemed acceptable even for these areas.
Moreover, the proponent was of the opinion that the risk impact for major
infrastructures and the community’s sensitive elements was located within the
acceptable range, as the return period is beyond the 10,000 year limit.
Besides, there are currently two projects under consideration which could be built
close to the pipeline planned by the proponent. These are the pipeline project linking
the Cacouna LNG terminal to Saint-Nicolas and the Pipeline Saint-Laurent oil pipeline
project linking Lévis and Montreal-East. In answer to a question from the Panel, the
proponent assessed the total individual risk for someone permanently in proximity to
these three pipelines, should they be realized and supposing that they would be built
in parallel. The proponent stated that his calculations were conservative, and that the
NEB, which must approve both pipelines, would require a common infrastructure for
the gas transiting from Rabaska and Cacouna, that is to say only one pipeline, not two
(DQ44.5, p. 1).
160 Rabaska Project – Implementation of an LNG Terminal and Related Infrastructure