Report - Agence canadienne d'évaluation environnementale

Impacts on the natural environment
undergo significant temperature changes like the one that would be caused, for
instance, by the sudden stop of a thermal discharge during the cold season 1 .
♦ Recommendation 18 — Should the project be carried out, the Panel recommends that
the proponent take measures to reduce the temperature of vaporizer discharge before it
reaches the river so as to minimize the impacts on fish habitat.
Furthermore, the effluent from the vaporizers would contain nitrite, nitrate and sodium
carbonate. Among these compounds, only nitrite and nitrate are covered by surface
water quality criteria. According to the proponent’s estimates, the chronic toxicity
criterion for nitrites, calculated based on the MDDEP’s Environmental Discharge
Objectives, would be exceeded only in a temporary and localized way. For this
reason, the proponent believes that vaporizer discharge would not have any
significant impact on fish habitat (PR3.3.1, p. 6.34; PR5.1, p. 3.67 and 2-74).
Vaporizer discharge should also comply with subsection 36 (3) of the Fisheries Act
(R.S.C. (1985), c. F-14), which prohibits the deposit of deleterious substances for the
fish or substances which represent an acute lethality for the latter. In that regard,
Environment Canada recommends adding biological tests to the effluents follow-up
program in order to assess their harmfulness.
♦ Recommendation 19 — The Panel recommends the characterization of vaporizer
discharge as well as a periodical follow-up of its compliance with the Environmental
Discharge Objectives and toxicity tests on aquatic life, to the satisfaction of
Environment Canada and the ministère du Développement durable, de
l’Environnement et des Parcs.
Hydrostatic tests on the pipeline
Hydrostatic tests on the natural gas pipeline pipes before their commissioning would
require pumping water from bodies of water or waterworks. Discharging the water
could affect the hydrology of the receiving body of water and may produce suspended
particulates.
The proponent plans to take energy dissipation measures during the discharge phase
to prevent soil erosion. He also plans to set the pumping and discharge rates so as
not to modify stream uses (PR5.1, p. 2.93). No information has been communicated
on the bodies of water that could be thus pumped, based on the maintenance of an
acceptable flow rate for the protection of aquatic life.
1. [On-line (March 31, 2007): www.mddep.gouv.qc.ca/Eau/criteres_eau/critere_s2.htm#température].
208 Rabaska Project – Implementation of an LNG Terminal and Related Infrastructure