Report - Agence canadienne d'évaluation environnementale

Impacts on the natural environment
♦ Recommendation 16 — The Panel recommends that the proponent assess the
cumulative environmental effects of the two projects related to his own, i.e. the two
power distribution lines and the access road leading to the terminal as regards the
extent of deforestation required.
Project impacts on water environments
Hydrology of the ruisseau Saint-Claude
The ruisseau Saint-Claude (Figure 13) is the main creek likely to be affected by the
construction of the terminal. A 955-m long segment of the western branch of the creek
would be diverted to bypass the facilities to the south. A new 975-m long bed would
be excavated to bypass the terminal to the west and to the south. The proponent is of
the view that these changes would not modify the remainder of the hydrographic
basin feeding this portion of the ruisseau Saint-Claude and would not significantly
modify its hydrology. Further downstream of the portion to be diverted, the basins
excavated to receive the storage tanks would intercept part of the local groundwater
at an estimated 0.007 m 3 /s flow rate in permanent regime. The proponent plans to
discharge this water into the ruisseau Saint-Claude, whose mean flow rate is at an
estimated 0.40 m 3 /s, 6 m 3 /s during the annual high water period and 0.02 m 3 /s during low
flow periods. In the latter case, a slight increase would occur, due to the planned discharge
(PR3.3.1, p. 2.22, 2.23 and 6.29; PR5.1, p. 3.39 to 3.40).
The MRNF said it was concerned by the impact of the groundwater drawdown on the
refuge pond located south-west of the creek and suggested that the pumped water be
discharged partly into the ruisseau Saint-Claude and partly into the refuge pond to
preserve these two ecosystems (DQ62.1). Moreover, the proponent suggested
different solutions to maintain an acceptable water balance in the ruisseau
Saint-Claude during the construction and operation phases of the terminal. However,
no information was provided on the impacts that interruption or abandonment of
terminal operations would have on the management of the ruisseau Saint-Claude flow
rate. Since the solutions put forward involve management of the flow rate, questions
persist in regard to the maintenance of an acceptable flow rate in the ruisseau Saint-
Claude when this pumping would be interrupted due to an operational shutdown.
♦ Recommendation 17 — The Panel recommends that the proponent develop a
management plan that would ensure the maintenance of an acceptable flow rate in the
ruisseau Saint-Claude and the integrity of the refuge pond. This management plan should
be to the satisfaction of Fisheries and Oceans Canada, the ministère du Développement
durable, de l’Environnement et des Parcs and the ministère des Ressources naturelles et de
la Faune, and should cover the terminal construction, operation and abandonment phases.
204 Rabaska Project – Implementation of an LNG Terminal and Related Infrastructure