FAP Hydrocarbon Monitoring
Total hydrocarbons (THC) refer to a broad family of chemicals that contain carbon and hydrogen atoms. Total hydrocarbons are the sum of non-reactive and reactive hydrocarbons. The major reactive hydrocarbon in the atmosphere is methane. Major worldwide sources of atmospheric methane include wetlands, ruminants such as cows, energy use, landfills, and burning biomass such as wood. Methane is the primary component of natural gas.
The reactive (or non-methane) hydrocarbons consist of many volatile organic compounds, some of which react with oxides of nitrogen in the atmosphere to form ozone. While Alberta does not have ambient air quality objectives (AAAQOs ) for total hydrocarbons, methane or non-methane hydrocarbons, the oxidation of hydrocarbons in the atmosphere contributes to an increased amount of nitrogen oxides and ozone, which do have objectives. Additionally, there are objectives for specific reactive hydrocarbons such as benzene, toluene, ethylbenzene, xylene, styrene and ethylene.
Table 1: Monthly average hydrocarbons (ppm) in 2012
|
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
|
Total Hydrocarbons (ppm) |
||||||||||||
|
Bruderheim |
* |
2.20 |
1.97 |
2.04 |
2.00 |
2.05 |
2.08 |
2.01 |
2.06 |
2.04 |
2.19 |
2.60 |
|
Fort Saskatchewan |
1.96 |
2.03 |
1.97 |
1.98 |
1.95 |
* |
1.74 |
1.77 |
1.75 |
1.65 |
1.64 |
1.91 |
|
Range Road 220 |
2.05 |
2.11 |
1.92 |
1.95 |
1.95 |
1.95 |
1.93 |
2.33 |
2.04 |
1.90 |
1.92 |
1.97 |
*data not available
Table 2: 1 hour Maximum hydrocarbons (ppm) in 2012
|
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
|
Total Hydrocarbons (ppm) |
||||||||||||
|
Bruderheim |
* |
4.6 |
2.6 |
5.3 |
8.5 |
6.4 |
6.5 |
6.4 |
6.4 |
6.5 |
6.4 |
8.6 |
|
Fort Saskatchewan |
3.9 |
3.1 |
3.0 |
2.7 |
2.6 |
* |
2.9 |
2.9 |
3.0 |
2.1 |
2.8 |
3.1 |
|
Range Road 220 |
3.7 |
3.2 |
4.1 |
4.6 |
3.3 |
2.9 |
2.8 |
* |
3.5 |
2.7 |
4.0 |
4.5 |
*data not available
Volatile Organic Compounds
Ethylene
Ethylene is a naturally occurring compound in ambient air. It is produced at low levels by soil microorganisms, algae, lichens and plants. Other natural sources of ethylene are volcanic activity and combustion in forest and grass fires. In Alberta, the concentration in ambient air resulting from these natural sources is typically low. Anthropogenic sources of ethylene include combustion of fossil fuels, and processing of natural gas in petrochemical facilities (e.g. production of plastics). The AAAQOs for ethylene are:
· 1-hour average concentration 1044ppb
· 3-day average 40 ppb
· Annual mean 26 ppb
When air quality monitoring data for 2012 in the FAP region was compared against the AAAQOs for ethylene, it was observed that:
· There were no exceedances of the AAAQO for ethylene in 2012
· The maximum one-hour concentration measured was 813 ppb (78% of the AAAQO)
· The annual average was highest at Ross Creek at 4.7 ppb (18% of the annual objective)
A summary of ethylene concentrations recorded in 2012 at individual stations are presented in the table below. For additional information see also the station by station summaries in the appendices of this report.
Table 3: Monthly average ethylene concentrations (ppb) in 2012
|
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Ann |
|
Range Road 220 |
1.6 |
1.5 |
1.9 |
1.5 |
2.5 |
1.9 |
2.7 |
2.0 |
6.2 |
2.5 |
1.9 |
2.0 |
2.4 |
|
Ross Creek |
1.7 |
1.9 |
1.1 |
1.1 |
0.4 |
0.5 |
2.0 |
2.3 |
11.9 |
26.8 |
5.3 |
1.6 |
4.7 |
FAP records exceedances of these substances, the following table summarizes the exceedances from 2008 to 2012.
Table 4: Exceedances Recorded from 2008 to 2012
|
Parameter Measured |
2012 |
2011 |
2010 |
2009 |
2008 |
|
|
Ammonia (NH3) |
1-hr |
0 |
0 |
1 |
0 |
0 |
|
Benzene (C6H6) |
1-hr |
1 |
2 |
0 |
1 |
1 |
|
Carbon Monoxide (CO) |
1-hr |
0 |
0 |
0 |
0 |
0 |
|
8-hr |
0 |
0 |
0 |
0 |
0 |
|
|
Ethyl benzene (C6H5CH2CH3) |
1-hr |
0 |
0 |
0 |
0 |
0 |
|
Ethylene (C2H4) |
1-hr |
0 |
0 |
0 |
0 |
0 |
|
3-day |
0 |
0 |
0 |
0 |
0 |
|
|
Annual |
0 |
0 |
0 |
0 |
0 |
|
|
Hydrogen Sulphide (H2S) |
1-hr |
163 |
15 |
0 |
11 |
0 |
|
24-hr |
28 |
2 |
0 |
0 |
0 |
|
|
Nitrogen dioxide (NO2) |
1-hr |
0 |
0 |
1 |
0 |
0 |
|
24-hr |
0 |
0 |
0 |
0 |
0 |
|
|
Annual |
0 |
0 |
0 |
0 |
0 |
|
|
Ozone (O3) |
1-hr |
0 |
4 |
0 |
3 |
1 |
|
Styrene (C6H5CH=CH3) |
1-hr |
0 |
0 |
0 |
0 |
6 |
|
Sulphur dioxide (SO2) |
1-hr |
7 |
30 |
42 |
8 |
15 |
|
24-hr |
0 |
2 |
6 |
1 |
1 |
|
|
30-day |
0 |
0 |
n/a |
n/a |
n/a |
|
|
Annual |
0 |
0 |
0 |
0 |
0 |
|
|
Particulate Matter Fine (PM2.5) |
1-hr |
28 |
47 |
n/a |
n/a |
n/a |
|
24-hr |
9 |
15 |
39 |
6 |
4 |
|
|
Toluene (C6H5CH3) |
1-hr |
0 |
0 |
0 |
0 |
0 |
|
Xylenes (o-, m- and p- isomers) |
1-hr |
0 |
0 |
0 |
n/a |
n/a |
Benzene, toluene, ethylbenzene, o-xylene, mp-xylenes, total xylene and styrene (BTEX/S)
BTEX/S fall into the group of compounds known as non-methane or reactive hydrocarbons discussed earlier in this report. These compounds are typically found in petroleum products, such as gasoline and diesel fuel and have a characteristic strong odour. BTEX/S has been measured on a semi-continuous (four samples per hour) basis at the Scotford 2 AQM station since January 2007. The Alberta Ambient Air Quality Objectives for BTEX/S are as follows:
· Benzene 1-hr average: 9ppb
(C6H6)
· Toluene 1-hour average: 499 ppb
(C6H5CH3) 24-hour average: 106 ppb
· Ethyl benzene 1-hour average 460 ppb
(C6H5CH2CH3)
· Xylenes 1-hour average 529 ppb
o-, m- and p- isomers 24-hour average 161 ppb
(C6H4(CH3)2)
· Styrene 1-hour average 52 ppb
(C6H5CH=CH2)
· A new annual average for Benzene was set in 2012: at 0.9ppb
When 2012 air quality monitoring data for 2012 was compared against the AAAQOs for BTEX/S, it was observed that:
· There was one exceedance of the 1-hour AAAQO for Benzene with a 1-hour average recorded value of 9.8 ppb.
· There were no exceedances for any of the other BTEX/S chemicals.
· There were no 24-hr AAAQO exceedances for any of the BTEX/S chemicals.
· The annual average for Benzene in 2012 was 0.14 ppb (15% of the objective)
A summary of ethylene concentrations recorded in 2012 at individual stations are presented in the table below.
Table 6: Monthly average BTEX/S concentrations (ppb) in 2012
|
|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
|
Benzene (ppb) |
0.42 |
* |
0.16 |
0.08 |
0.06 |
0.07 |
0.15 |
0.10 |
0.18 |
0.12 |
0.12 |
0.08 |
|
Toluene (ppb) |
0.10 |
* |
0.09 |
0.00 |
0.00 |
0.01 |
0.02 |
0.00 |
0.06 |
0.04 |
0.03 |
0.14 |
|
Ethylbenzene (ppb) |
0.01 |
* |
0.04 |
0.03 |
0.00 |
0.02 |
0.04 |
0.00 |
0.00 |
0.01 |
0.01 |
0.02 |
|
m,p-xylene (ppb) |
0.01 |
* |
0.02 |
0.05 |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
0.00 |
0.01 |
0.03 |
|
o-xylene (ppb) |
0.01 |
* |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
|
Styrene (ppb) |
0.01 |
* |
0.01 |
0.00 |
0.00 |
0.01 |
0.03 |
0.01 |
0.01 |
0.00 |
0.01 |
0.02 |
|
Xylenes (ppb) |
0.02 |
* |
0.04 |
0.06 |
0.00 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.01 |
0.04 |