Environmental Assessment
Volume B-6
Mine
Reclamation and Closure Plan
Ambatovy Project
400
January 2006
It is expected that transportation corridors will remain in-place for a post-closure
period to facilitate site access for monitoring. Once the area has stabilized the
road surfaces will be reclaimed unless decided otherwise by regional authorities.
The road surfaces will be scarified, and recontoured to blend in with the
surroundings, and revegetated. Temporary erosion control measures will be
implemented as necessary until surfaces have sufficiently stabilized.
Considerable experience in reclaiming old exploration roads has been gained on
the project to date and will contribute to the methodology of road reclamation
following mine closure.
6.7
RECLAMATION PLAN
6.7.1
Erosion Control
The following general mitigation options will be employed as appropriate to
prevent water erosion:
•
salvage topsoil where feasible (except ferricrete soils) and store away
from areas of potential erosion;
•
construct temporary cross ditches to redirect surface runoff;
•
construct temporary berms of imported logs, construction timbers,
sandbags or other material as appropriate and available;
•
construct berms with overburden in areas where topsoil has been
stripped;
•
construct mine roads so natural drainage patterns are not impeded and in
a manner that runoff to road ditches enters natural drainage systems or
contoured containment areas;
•
use temporary erosion control measures such as mulches, mats, netting,
or straw crimping to control erosion before a protective vegetative cover
is established;
•
apply tackifiers where necessary to stabilize soils and use hydroseeders
for seeding on steep slopes; and
•
promptly seed exposed areas and topsoil stockpiles with a self-
sustaining, erosion-controlling seed mix appropriate to the region. It is
suggested that Vetiver grass (Vetiveria zizanioides) be planted in strips
parallel to slopes (NRC 1993). Other species can then be planted
between the strips of Vetiver.
