Environmental Assessment
Volume E-3.6
Tailings Facility
Natural Risks
Ambatovy Project
40
January 2006
3.6
NATURAL RISKS
3.6.1
Introduction
This section presents the Environmental Assessment for the risks of natural
hazards to the public and environment due to the tailings facility, as per the
Ambatovy Project (the project) Terms of Reference.
3.6.2
Study Area
The tailings Local Study Area (LSA) is shown in the tailings and plant site area
plan presented in Volume A, Figure 7.2-3. This preferred option for tailings
storage is in the Toamasina area located about 2 km west of Route National
(RN) 2 (between Toamasina and Antananarivo) and about 8 km southwest of
Toamasina. The tailings facility covers an area of approximately 9 km
2
and
provides tailings storage for the entire 27-year mine life. The area has been
deforested and has a cover of secondary vegetation (Volume J, Appendix 1.1).
Natural hazards such as earthquakes can originate from a much larger regional
area that was studied as appropriate to determine the potential impacts at the
tailings site.
3.6.3
Baseline Summary
The Environmental Assessment is based on a separate study on natural hazards
and risk assessment for the tailings facility (Knight Piesold 2005b, which is
provided in Volume I, Appendix 6.1). In this reference study, the baseline for the
tailings facility setting is described in terms of location, existing land use,
topography, geology, climate and seismicity. Potential natural hazards, potential
consequences of failure due to natural hazards and risks downstream of the
tailings facility were assessed.
Resources downstream of the tailings facility include small human settlements,
potable water and agricultural land. Natural vegetation, including bamboo and
banana leaves are also used for the building of houses and roofing. One dolerite
quarry, operating as a one-man business on a very small scale, exists within the
boundaries of the current investigation area and is situated in the western portion
of the site.
Baseline data for natural hazards included climate data describing hydrological
hazards and earthquake data describing seismicity hazards.
