Environmental Assessment
Volume B-3.4
Mine
Climate and Air Quality
Ambatovy Project
45
January 2006
milling industries (World Bank 1995). The World Bank also provides
recommendations for certain pollutant thresholds (i.e., SO
2
, NO
2
, PM
10
and Total
Suspended Particulate [TSP]) when specific country or project guidelines are not
available. The thresholds used for defining a moderately degraded airshed were
used as the TSP criteria. In the absence of World Bank guidelines, the WHO
guidelines were used (i.e., lead and mercury). Table 3.4-2 summarizes the air
quality criteria used for the mine.
Table 3.4-2 Ambient Air Quality Criteria
World Bank
(a)
Parameter
Open Pit
Mining
Moderately
Degraded Airshed
(b)
WHO
(c)
Criteria Used
for Project
Sulphur Dioxide (SO
2
)
24-hour average [µg/m³]
500
150
125
500
annual average [µg/m³]
100
80
50
100
Nitrogen Dioxide (NO
2
)
24-hour average [µg/m³]
200
150
—
200
annual average [µg/m³]
100
100
40
100
Total Suspended Particulate (TSP)
annual average [µg/m³]
—
80
—
80
PM
10
24-hour average [µg/m³]
500
150
—
(d)
500
annual average [µg/m³]
100
50
—
(d)
100
Lead
annual [µg/m³]
—
—
0.5
0.5
Mercury
annual [µg/m³]
—
—
1
1
(a)
Source: World Bank 1995, 1998.
(b)
These values are based on pollutant-specific recommendations from the World Bank when country guidelines are
not available.
(c)
Source: WHO 2000.
(d)
WHO recommends a risk-based approach for assessing the effects of PM
10
, therefore no guidelines are provided.
“—” Indicates no criteria available.
The impact assessment methodology used for the Ambatovy Project has been
described in detail in Volume A, Section 7 and involves the evaluation of
residual effects. The residual effects for air were classified using quantification
criteria to determine environmental consequence. Each impact is first described
in terms of the following criteria: magnitude, geographic extent and duration.
Two additional criteria were also used for the air quality assessment: reversibility
and frequency. Table 3.4-3 details the Impact Description Criteria for the air
quality component of the EA.
