HomeMy WebLinkAboutAppendix A - AQMD ThresholdsSouth Coast
Air Quality Management District
21865 Copley Drive, Diamond Bar, CA 91765 -4182
(909) 396 -2000 • www.agmd.gov
SCAQMD Air Quality Significance Thresholds
Mass Daily Thresholds a
Pollutant Construction b Operation'
NOx
100 lbs /day
55 lbs /day
VOC
75 lbs /day
55 lbs /day
PM10
150 lbs /day
150 lbs /day
PM2.5
55 lbs /day
55 lbs /day
Sox
150 lbs /day
150 lbs /day
CO
550 lbs /day
550 lbs /day
Lead
3 lbs /day
3 lbs /day
Toxic Air Contaminants (TACs) and Odor Thresholds
TACs
Maximum Incremental Cancer Risk> 10 in I million
(including carcinogens and non - carcinogens)
Hazard Index? LO (project increment)
Odor
I Project creates an odor nuisance pursuant to SCAQMD Rule 402
Ambient Air Quality for Criteria Pollutants d
NO2
SCAQMD is in attainment; project is significant if it causes or
contributes to an exceedance of the following attainment standards:
1 -hour average
0.25 ppm (state)
annual average
0.053 ppm (federal)
PM 10
24 -hour average
10.4 µg /m3 (construction)' & 2.5 µg/m' (operation)
annual geometric average
1.0 µg/m3
annual arithmetic mean
20 µg /ms
PM2.5
24 -hour average
10.4 µg /m3 (construction)' & 2.5 Rg/ms (operation)
Sulfate
24 -hour average
1 µg/ms
CO
SCAQMD is in attainment; project is significant if it causes or
contributes to an exceedance of the following attainment standards:
1 -hour average
20 ppm (state)
8 -hour average
9.0 ppm (state /federal)
'Source: SCAQMD CEQA Handbook (SCAQMD, 1993)
b Construction thresholds apply to both the South Coast Air Basin and Coachella Valley (Salton Sea and Mojave Desert Air Basins).
For Coachella Valley, the mass daily thresholds for operation are the same as the construction thresholds.
d Ambient air quality thresholds for criteria pollutants based on SCAQMD Rule 1303, Table A -2 unless otherwise stated.
Ambient air quality threshold based on SCAQMD Rule 403.
KEY: Ibs /day = pounds per day ppm = parts per million gg/m' =microgram per cubic meter ? greater than or equal to
(Rev. December 2007)