Environmental Assessment
Volume C-3.1
Slurry Pipeline
Topography and Geomorphology
Ambatovy Project
21
January 2006
the route. Virtually all impacts will occur at the time of construction, including
both the pipeline itself and the development of access routes to and along the
pipeline.
3.1.5.5 Impact Analysis
Residual Impacts
Following mitigation, the residual effects during each project period are
summarized in Table 3.1-2.
Table 3.1-2 Potential Effects and Residual Impacts for Topography and
Geomorphology
Project Period
Potential Effects
Mitigation
Residual Impacts
construction
removal and disturbance of important
topographic features important for social or
biological reasons (Torotorofotsy Wetlands)
changes in the landscape due to pipeline
construction
erosion control;
water management;
stable slope engineering;
progressive reclamation
low magnitude/long-term
modification of row and
access routes
operations
changes in the landscape and slopes which
may represent important issues over the
long term to stakeholders and biodiversity
erosion control;
water management;
stable slope engineering;
progressive reclamation
low magnitude/long-term
modification of RoW and
access routes
closure
n/a
n/a
n/a
n/a Not applicable.
The existing topography of the LSA is hilly with relatively steep slopes, except at
the eastern end of the slurry pipeline corridor, which extends into level terrain in
coastal areas. The areas affected by topographic change due to the slurry
pipeline are mainly the steep-sided valleys.
The portion of the pipeline traversing the Torotorofotsy Wetlands will pass over
level terrain along an existing, disturbed corridor. Impacts to topography are
therefore not expected to have negative implications for this unique topographic
feature, given the successful implementation of mitigation measures to prevent
erosion into the wetlands themselves.
The slurry pipeline and its associated access corridors will have a direct, but
localized impact on the landscape. Generally, impacts will be long-term, because
the terrain will not be changed back to its original form as the time of closure.
The magnitude of the changes are considered low during construction and
operations, as the pipeline affects only a narrow corridor and the associated linear
access routes, and mitigation is expected. The low impact magnitude assumes
