Environmental Assessment
Volume B-4.3
Mine
Fish and Aquatic Resources
Ambatovy Project
272
January 2006
Table 4.3-10 Residual Impact Classification for Effects on Aquatic Species
Abundance and Survival
Phase
Direction Magnitude Geographic
Extent
Duration Reversibility Frequency Environmental
Consequence
Effect: Habitat Modification
construction negative
high
local
long-
term
no
medium
high
operations
mine / region
negative
medium
local
long-
term
no
medium
moderate
operations
downstream
negative
low
local
long-
term
no
medium
low
operations
Torotorofotsy
negative
low
local
long-
term
no
medium
low
Effect: Change to Fish and Ecosystem Health
construction negative
low
local
short-
term
yes
low
negligible
operations
negative
medium
local
long-
term
yes
medium
moderate
Effect: Establishment of Exotic Species
operations
negative
low
local
long-
term
no
medium
moderate
closure
negative
low
local
long-
term
no
medium
moderate
Effect: Restoration and Species Re-introduction
operations
(a)
positive
n/a
n/a
n/a
n/a
n/a
n/a
closure
positive
n/a
n/a
n/a
n/a
n/a
n/a
(a)
Effect during operations assumed to be off-site, i.e., captive breeding programs.
n/a Criteria not ranked for positive impacts.
As noted for the previous key question, the high residual impacts after mitigation
confirm the need for additional off-site conservation activities.
Monitoring
•
Additional surveys in the mine footprint area to help focus species
salvage efforts prior to construction; for fish in streams and
invertebrates in ephemeral ponds.
•
Water flow and quality monitoring will be implemented downstream to
ensure protection of downstream habitats.
•
Monitor to ensure that conservation measures to preserve the ephemeral
ponds are working successfully in both on-site and off-site conservation
areas.
