Environmental Assessment
Volume E-2
Tailings Facility
Project Description
Ambatovy Project
9
January 2006
2
PROJECT DESCRIPTION
The criteria for tailings facility site selection were based on factors outlined in
the previous section and the total required storage capacity to satisfy both solids
storage and water management objectives. Based on preliminary water balance
analyses, the required operational water storage is estimated to be 7 to 8 million
cubic metres (Mm
3
) while the environmental design storm (EDS) storage
allowance is estimated to be 6 Mm
3
. Therefore a total required storage capacity
of about 200 Mm
3
for tailings, water storage and freeboard has been used for
preliminary design.
2.1
DESIGN STANDARDS
The design basis and criteria for the tailings facility are based on International
Standards for the design of dams. In particular, all aspects of the design of the
tailings facility have been completed in compliance with the following three
documents:
•
Canadian Dam Association (CDA) Dam Safety Guidelines (CDA 1999);
•
International Commission on Large Dams (ICOLD), in particular
Tailings Dams and Seismicity - Review and Recommendations (ICOLD
1995); and
•
The Mining Association of Canada (MAC) Guide to the Management of
Tailings Facilities (MAC 1998).
On tailings dams, the CDA guidelines state that “Tailings dams and their
appurtenant structures must be protected against the same hazards and to the
same extent as embankment dams…”.
2.2
GENERAL DESIGN CRITERIA
The following general project design criteria have been used for the design of the
tailings facility:
•
The preliminary design requirements are based on an annual production
of 60,000 tons of product from the mine.
•
The operating life of the project is 27 years.
•
The estimated tailings flow is approximately 20,500 dry tonnes per day
at 38% solids.
