Air Quality Section
Information Brochures and Reports
TILSTON AIR QUALITY:
FINAL REPORT ON THE AIR QUALITY MONITORING PROGRAM
July 1998 to June 2000
VOLUME I.
SUMMARY OF AMBIENT AIR QUALITY MONITORING PROGRAM
BACKGROUND
Concerns had been raised by residents in the Tilston area that
the oil and gas activities in the region may be affecting local
air quality with potential impacts to their health and livestock.
In response to these concerns, Manitoba Conservation had conducted
an outdoor air quality monitoring program for various air
pollutants from July 1998 to June 2000.
Manitoba Conservation has previously released interim reports
which summarized the air quality monitoring activities that had
been undertaken in the Tilston area and the air quality monitoring
data that had been collected. The first report was released in
August 1999; updates were released in November 1999, January 2000,
March 2000, April 2000, and June 2000. Volume I of this final
report provides a summary of all the monitoring that has been
undertaken since the beginning of the program. Volume II contains
all of the monitoring data collected.
MONITORING ACTIVITIES
The Tilston air quality monitoring program, which was first
started in July 1998, had developed and expanded since that time
as additional air quality issues arose. The program was developed
in consultation with the Tilston Community Advisory Group (CAG).
At the start of the monitoring program in July 1998, Manitoba
Conservation only conducted limited outdoor air monitoring for
sulphur dioxide in W. Campbell's farm yard (Farm Yard #1) in the
Rural Municipality of Albert (9-6-29). This monitoring location
was 1.6 km (1 mile) directly east of the Tundra Oil and Gas Ltd.
oil battery located at 8-8-6-29 W.P.M. ("the battery").
The air quality monitoring program was expanded in early 1999
because of additional questions that had arisen regarding the air
quality in the area. The sulphur dioxide monitor was re-located
from its original location at W. Campbell's farm to a monitoring
trailer on J. Anderson's farm yard (Farm Yard #2) about 1 km
south at 4-6-29 W.P.M. This new location was selected in order to
measure sulphur dioxide levels in another area where health
concerns had been reported. Moving the monitoring site also
allowed the trailer to be connected to a telephone line. Data from
the sulphur dioxide monitor could then be directly accessed by
Manitoba Conservation staff in Brandon and Winnipeg.
A second sulphur dioxide monitoring site was established near
the oil well furthest east of the battery (6-9 Well Site). A
monitoring trailer, also with a telephone connection, had been
placed on the site. This site was chosen to give an indication of
air quality in an area closer to the battery. Wind speed and
direction were monitored at this location since air flows were
relatively unobstructed by buildings or shelter belts.
In addition to the two sulphur dioxide monitors, two hydrogen
sulphide monitors were obtained. These instruments, which were
able to monitor environmental levels of hydrogen sulphide in the
parts per billion range, were located with the two sulphur dioxide
monitors.
Continuous monitoring at the two new locations started in the
beginning of April 1999 for sulphur dioxide and at the end of
April 1999 for hydrogen sulphide. One of the hydrogen sulphide
monitors was removed from service for about 6 weeks in June and
July. This monitor was returned to its supplier for maintenance
because it had not been functioning reliably; it was placed back
into operation on July 27th in the trailer located at the 6-9 Well
Site.
Sampling for volatile organic compounds (VOC's) was also
undertaken as part of the expanded monitoring program. Samples of
1-hour duration were taken using a SUMMA canister; these samples
were then shipped to the Environment Canada lab in Ottawa for
analysis. A limited number of volatile organic compound (VOC)
samples were taken in the area in the spring of 1999. The VOC
sampling program continued during the summer with the collection
of a VOC sample about once per week; these samples were collected
under varying conditions and at different locations in the area of
interest. Additional equipment was also obtained to enable VOC
sample collection throughout the day (i.e., samples of
24-hour duration) as an alternate means of collecting VOC samples.
This equipment was installed September 1, 1999 at the Farm Yard #2
site.
Monitoring for aldehydes and ketones was undertaken starting on
August 13, 1999 when aldehyde/ketone monitor was installed at the
Farm Yard #2 site. Once a week, a 24-hour sample was collected for
later analysis by Environment Canada. Aldehydes (such as
formaldehyde) and ketones (such as acetone) are classes of
chemical compounds which are known to be irritating to the eyes
and throat at higher concentrations.
A sulphuric acid mist sampler was installed on October 1, 1999
at the 6-9 Well Site monitoring station. This sampler collected
and analyzed 1-hour air samples for sulphuric acid. However, this
instrument was less sensitive than the other types of samplers and
so could only provide information on somewhat higher environmental
levels of pollutants. Monitoring with the sulphuric acid mist
sampler was discontinued in December 1999.
In addition to the stationary monitors, Manitoba Conservation
also purchased a portable analyzer to measure both hydrogen
sulphide and sulphur dioxide. This instrument allowed staff to
measure levels of these two air contaminants in other locations in
the area; however, the portable analyzer was not able to measure
contaminant levels as low as the fixed hydrogen sulphide and
sulphur dioxide monitors could. Sampling was undertaken both
randomly and on a planned basis.
In June 2000, the Tilston air quality monitoring program was
discontinued. At the end of this program, the program had been
monitoring for sulphur dioxide and hydrogen sulphide at the two
monitoring locations (i.e., Farm Yard #2 and 6-9 Well
Site), and volatile organic compounds (VOC's) and aldehydes and
ketones at the Farm Yard #2 site.
SUMMARY OF AIR QUALITY MONITORING RESULTS
Sulphur Dioxide
Sulphur dioxide was the first air pollutant to be monitored in
the Tilston area. Consequently, more data are available for this
air contaminant than for any of the other pollutants.
The sulphur dioxide monitoring data collected during the
monitoring program are summarized in Tables 1a, 1b, and 1c for
each of the three sulphur dioxide monitoring sites. (Note: The
first monitoring location (i.e., Farm Yard #1) was only
operated until March 1999.) The three monitoring sites and the
battery are shown in Figure 1.
Table 1a. Station # 6111 At Farm Yard #1 Site - Sulphur
Dioxide (SO2)
(Parts Per Million (PPM))
|
Date
|
Percentage of Data that is Valid
|
Average
|
Maximum
Data Values
1-HOUR : 24-HOUR
|
Number of Samples Above Air Quality Objective
1-HOUR : 24-HOUR
|
|
JUL 22/98 MAR 31/99 |
92 |
0.00 |
1.05 |
0.05 |
4 |
0 |
|
JUL/98 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
AUG/98 |
96 |
0.00 |
1.05 |
0.05 |
4 |
0 |
|
SEP/98 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
OCT/98 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
NOV/98 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
DEC/98 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
JAN/99 |
74 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
FEB/99 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
MAR/99
(end of monitoring) |
88 |
0.00 |
0.00 |
0.00 |
0 |
0 |
Manitoba Air Quality Objectives for SO2:
1-hour average: 0.34 ppm
24-hour average: 0.11 ppm
Table 1b. Station # 6113 At 6-9 Well Site - Sulphur
Dioxide (SO2)
(Parts Per Million (PPM))
|
Date
|
Percentage of Data that is Valid
|
Average
|
Maximum
Data Values
1-HOUR : 24-HOUR
|
Number of Samples Above Air Quality Objective
1-HOUR : 24-HOUR
|
|
APR 16/99 JUNE 16/00 |
94 |
0.00 |
0.06 |
0.01 |
0 |
0 |
|
APR/99 |
93 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
MAY/99 |
95 |
0.00 |
0.02 |
0.00 |
0 |
0 |
|
JUN/99 |
82 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
JUL/99 |
96 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
AUG/99 |
96 |
0.00 |
0.02 |
0.00 |
0 |
0 |
|
SEPT/99 |
96 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
OCT/99 |
95 |
0.00 |
0.04 |
0.01 |
0 |
0 |
|
NOV/99 |
95 |
0.00 |
0.04 |
0.01 |
0 |
0 |
|
DEC/99 |
92 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
JAN/00 |
95 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
FEB/00 |
95 |
0.00 |
0.06 |
0.01 |
0 |
0 |
|
MAR/00 |
96 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
APR/00 |
94 |
0.00 |
0.03 |
0.00 |
0 |
0 |
|
MAY/00 |
91 |
0.00 |
0.02 |
0.00 |
0 |
0 |
|
JUNE 1-16/00
(end of monitoring) |
91 |
0.00 |
0.03 |
0.00 |
0 |
0 |
Manitoba Air Quality Objectives for SO2:
1-hour average: 0.34 ppm
24-hour average: 0.11 ppm
Table 1c. Station # 6112 At Farm Yard #2 Site - Sulphur
Dioxide (SO2)
(Parts Per Million (PPM))
| Date |
Percentage of Data that is
Valid |
Average |
Maximum
Data Values
1-HOUR : 24-HOUR |
Number of Samples
Above Air Quality Objective
1-HOUR : 24-HOUR |
|
APR 7/99 JUNE 4/00 |
94 |
0.00 |
0.02 |
0.01 |
0 |
0 |
|
APR/99 |
92 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
MAY/99 |
95 |
0.00 |
0.02 |
0.00 |
0 |
0 |
|
JUN/99 |
94 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
JUL/99 |
94 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
AUG/99 |
95 |
0.00 |
0.02 |
0.00 |
0 |
0 |
|
SEPT/99 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
OCT/99 |
94 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
NOV/99 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
DEC/99 |
93 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
JAN/00 |
88 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
FEB/00 |
95 |
0.00 |
0.02 |
0.01 |
0 |
0 |
|
MAR/00 |
92 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
APR/00 |
93 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
MAY/00 |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
|
JUNE 1-4/00
(end of monitoring) |
96 |
0.00 |
0.00 |
0.00 |
0 |
0 |
Manitoba Air Quality Objectives for SO2:
1-hour average: 0.34 ppm
24-hour average: 0.11 ppm
At the first monitoring location (i.e., Farm Yard #1),
the sulphur dioxide monitor had not detected any sulphur dioxide
in the period from July to December 1998 except for a
two-week period in August 1998. At this time, the monitoring
equipment recorded sulphur dioxide gas for short durations on 9 occasions.
During the week of January 4 to January 11, 1999, however, the
monitor apparently recorded elevated levels of sulphur dioxide for
extended periods of time. There were, however, significant
uncertainties regarding the validity of the January data because
of technical difficulties with the air quality monitoring support
systems, inconsistencies with a concurrent informal health survey
of the area, and inconsistency with emissions from the battery.
After a thorough review, no conclusive statement could be made
regarding the air quality in the area based on the data recorded
during this week. For the remainder of the sulphur dioxide
monitoring conducted at this site, sulphur dioxide had not been
detected.
Except for relatively few occasions of very low readings, no
sulphur dioxide had been detected at the sulphur dioxide monitors
located at the two new monitoring sites of the expanded air
quality monitoring program (See Tables 1b and 1c). Sulphur dioxide
was detected at these two stations less
than two percent of the time. The
sulphur dioxide concentrations measured were significantly below
both the 1-hour and 24-hour air quality objectives of 0.34 ppm and
0.11 ppm, respectively. The maximum recorded 1-hour average
sulphur dioxide concentrations were 0.06 ppm at the 6-9 Well Site
(February 4, 2000) and 0.02 ppm at the Farm Yard #1 site (May 28,
1999; August 13, 1999; February 11, 2000).
No levels of sulphur dioxide were ever recorded on the less
sensitive portable analyzer during
periodic monitoring at various locations in the area of
complaints.
Hydrogen Sulphide
Monitoring for hydrogen sulphide took place at the two new
monitoring sites (i.e., Farm Yard #2 and 6-9 Well Site)
starting at the end of April 1999. One of the hydrogen sulphide
monitors was removed from service for maintenance for about 6
weeks in June and July 1999. No reliable data were available for
this monitor for the period from May 5, 1999 to July 27, 1999.
The hydrogen sulphide monitoring data collected during the
monitoring program are summarized in Tables 2a and 2b.
Table 2a. Station # 6113 At 6-9 Well Site - Hydrogen
Sulphide (H2S)
(Parts Per Billion (PPB))
|
Date
|
Percentage of Data that is Valid
|
Average
|
Maximum
Data Values
1-HOUR : 24-HOUR
|
Number of Samples Above Air Quality Objective
1-HOUR
|
|
MAY 7/99 JUNE 16/00 |
83 |
0.14 |
36.0 |
6.5 |
12 |
|
MAY/99 |
93 |
0.04 |
6.5 |
0.8 |
0 |
|
JUN/99 |
24 |
0.12 |
6.1 |
0.9 |
0 |
|
JUL/99 |
15 |
0.74 |
9.8 |
1.9 |
0 |
|
AUG/99 |
96 |
0.76 |
36.0 |
6.5 |
10 |
|
SEPT/99 |
96 |
0.15 |
5.9 |
1.1 |
0 |
|
OCT/99 |
94 |
0.03 |
1.4 |
0.2 |
0 |
|
NOV/99 |
95 |
0.15 |
11.2 |
1.1 |
1 |
|
DEC/99 |
92 |
0.08 |
8.2 |
0.7 |
0 |
|
JAN/00 |
95 |
0.04 |
9.1 |
0.5 |
0 |
|
FEB/00 |
95 |
0.02 |
1.4 |
0.2 |
0 |
|
MAR/00 |
95 |
0.01 |
2.1 |
0.2 |
0 |
|
APR/00 |
95 |
0.02 |
4.7 |
0.4 |
0 |
|
MAY/00 |
91 |
0.09 |
4.3 |
0.6 |
0 |
|
JUNE 1-8/00
(end of monitoring) |
91 |
0.09 |
11.6 |
1.0 |
1 |
Manitoba Ambient Air Quality Objective for H2S:
1-hour average: 11.0 ppb
Table 2b. Station # 6112 At Farm Yard #2 Site - Hydrogen
Sulphide (H2S)
(Parts Per Billion (PPB))
|
Date
|
Percent of Data that IsValid
|
Average
|
Maximum
Data Values
1-HOUR : 24-HOUR
|
Number of Samples Above Air Quality Objective
1-HOUR
|
|
MAY 5/99 JUNE 4/00 |
87 |
0.04 |
23.2 |
2.1 |
4 |
|
MAY/99 |
0 |
-- |
-- |
-- |
0 |
|
JUN/99 |
70 |
0.02 |
1.2 |
0.2 |
0 |
|
JUL/99 |
94 |
0.12 |
21.4 |
2.1 |
1 |
|
AUG/99 |
96 |
0.17 |
7.5 |
1.1 |
0 |
|
SEPT/99 |
96 |
0.03 |
2.4 |
0.3 |
0 |
|
OCT/99 |
95 |
0.01 |
0.9 |
0.1 |
0 |
|
NOV/99 |
96 |
0.01 |
1.2 |
0.1 |
0 |
|
DEC/99 |
93 |
0.04 |
11.5 |
1.0 |
2 |
|
JAN/00 |
95 |
0.00 |
1.5 |
0.1 |
0 |
|
FEB/00 |
95 |
0.05 |
23.2 |
1.3 |
1 |
|
MAR/00 |
96 |
0.00 |
0.0 |
0.0 |
0 |
|
APR/00 |
93 |
0.00 |
0.0 |
0.0 |
0 |
|
MAY/00 |
96 |
0.02 |
3.3 |
0.3 |
0 |
|
JUNE 1-4/00
(end of monitoring) |
96 |
0.00 |
0.0 |
0.0 |
0 |
Manitoba Ambient Air Quality Objective for H2S:
1-hour average: 11.0 ppb
Low levels of hydrogen sulphide have been detected on several
occasions at both monitoring stations, usually in the early hours
of the day. For most of these occasions, the levels recorded did
not exceed the provincial air quality guideline for hydrogen
sulphide of 11 parts per billion (ppb); however, if any local
residents had been in the area at the time, they might have been
able to smell some hydrogen sulphide. At the monitor at the 6-9
Well Site, the levels of hydrogen sulphide tended to be slightly
higher than at the Farm Yard #2 site. Hydrogen sulphide was
detected by the instruments at the two sites less than 7% of the
time.
Elevated levels of hydrogen sulphide (i.e., above the
provincial air quality guideline of 11 ppb) were detected on
occasion. Most of these incidents appeared to occur during the
early morning hours under calm wind conditions. (These incidents
are described in Table 3.) While the hydrogen sulphide levels
during these incidents could have been smelled, the levels were
much less than levels reported in the literature as causing health
effects such as irritation to occur (e.g., about 2,000 ppb
in asthmatics following a 30-minute exposure).
Table 3. Exceedances of the H2S Air Quality
Guideline
|
Monitoring Site
|
Date
|
Time
|
Hourly Average H2S Concentration
(ppb)
|
Wind Speed - Wind Direction(1)
|
|
Farm Yard #2 |
July 10, 1999 |
22:00 |
21.4 |
2.1 km/hr - SSW (209o) |
|
December 29, 1999 |
18:00 |
11.3 |
10.9 km/hr - NW (319o) |
|
20:00 |
11.5 |
8.0 km/hr - ENE (62o) |
|
February 7, 2000 |
7:00 |
23.2 |
2.4 km/hr - W (263o) |
|
6-9 Well Site |
August 6, 1999 |
1:00 |
15.1 |
7.3 km/hr - WSW (255o) |
|
6:00 |
21.1 |
4.0 km/hr - NE (44o) |
|
August 10, 1999 |
1:00 |
12.5 |
6.3 km/hr - W (262o) |
|
2:00 |
13.0 |
7.1 km/hr - W (263o) |
|
August 13, 1999 |
6:00 |
15.0 |
3.2 km/hr - WNW (289o) |
|
August 24, 1999 |
2:00 |
13.4 |
6.1 km/hr - W (271o) |
|
3:00 |
15.1 |
5.3 km/hr - WSW (257o) |
|
5:00 |
27.6 |
6.3 km/hr - WSW (258o) |
|
6:00 |
27.2 |
3.3 km/hr - W (263o) |
|
7:00 |
36.0 |
4.9 km/hr - W (262o) |
|
November 5, 1999 |
17:00 |
11.2 |
8.7 km/hr - W (259o) |
|
June 7, 2000 |
5:00 |
11.6 |
2.0 km/hr - W (267o) |
_________________________________
(1) The wind
direction is defined as the direction from which the wind is
blowing. The wind direction is given both by sector (e.g. SSW) and
degrees (e.g. 209o) where North is 0o, East
is 90o, South is 180o and West is 270o.
No levels of hydrogen sulphide were recorded on the less
sensitive portable analyzer during monitoring at various locations
in the area of complaints.
Sulphuric Acid Mist
The sulphuric acid monitor, on short-term loan from Environment
Canada, did not detect any sulphuric acid mist in the vicinity of
the 6-9 Well Site during the 2 months that it was operated. This
monitor was returned to Environment Canada in December 1999.
Volatile Organic Compounds (VOC's)
In total, 18 1-hour and 42 24-hour air samples for determining
volatile organic compounds (VOC) were taken in the area. The VOC
data are summarized in Table
4.
While the total number of samples was relatively limited, they
did provide some indication of the VOC's (both natural and
man-made) present in the area. Many of these compounds are
widespread and would be present in an air sample taken anywhere in
the province, especially considering the low detection limit of
the analysis for the VOC's.
In downtown Winnipeg, 24-hour VOC samples have been taken every
six days since 1990. In general, the levels of VOC's measured in
the Tilston samples were similar to or less than levels observed
in Winnipeg during the years from 1990 to 1998. Many of the VOC's
in the Tilston samples, especially those reported at extremely low
concentrations, were near the lower limit of detection of the
methodology used to measure the VOC's. For some of the VOC's, air
quality criteria were available from Ontario or Quebec; the levels
measured for these VOC's were found to be substantially less than
their criteria.
Somewhat higher than expected concentrations of Freon 113 and
dichloromethane were detected in the first four VOC samples. It
was later determined that the Freon 113 and dichloromethane levels
were the result of trace contamination of the valve on the SUMMA
canister used to collect the samples.
A 1-hour VOC sample was taken on August 23, 1999 at a time and
location where hydrogen sulphide could be smelled. Reviewing the
results for this sample did not reveal any significant differences
from other VOC samples that have been taken. Only 5 of the 147
compounds were higher (but not significantly so) than in previous
samples from the Tilston area. The levels of these compounds were
within the range of the levels measured in Winnipeg and were
substantially less than any available air quality guidelines.
BTEX
The BTEX compounds (benzene, toluene, ethyl benzene, and
xylene), which are a subgroup of the VOC's, had been raised as an
air quality issue in the Tilston area since these compounds are
associated with hydrocarbon contamination, especially of soils. In
the VOC samples collected, the levels of BTEX compounds were
within the range of levels found in Winnipeg; they were also
significantly less than Ontario's or Quebec's air quality
standards for these compounds.
The air concentrations of the BTEX compounds are summarized in
Table 5a for the 1-hour samples and in Table 5b for the 24-hour
samples. Also shown are the relevant Ontario and Quebec air
quality guidelines.
Table 5a. Comparison of Winnipeg and Tilston BTEX
Concentrations
(1-hour samples)
|
Compound
|
Number of Samples
|
Average
(µg/m3)
|
Minimum
(µg/m3)
|
Maximum
(µg/m3)
|
Ontario Air Quality Standard(3)
(µg/m3)
|
|
WINNIPEG(1) - (1990 - 1998)
|
|
Benzene |
501 |
1.89 |
0.39 |
12.00 |
N/A |
|
Toluene |
500 |
5.98 |
1.26 |
54.40 |
2,000 |
|
Ethyl benzene |
501 |
0.88 |
0.05 |
6.49 |
4,000 |
|
m-Xylene and p-Xylene |
501 |
3.28 |
0.01 |
21.20 |
2,300 |
|
o-Xylene |
501 |
1.23 |
0.01 |
9.46 |
2,300 |
|
TILSTON(2)
|
|
Benzene |
18 |
0.31 |
0.12 |
0.66 |
N/A |
|
Toluene |
18 |
2.12 |
0.15 |
11.61 |
2,000 |
|
Ethyl benzene |
18 |
0.16 |
0.02 |
0.74 |
4,000 |
|
m-Xylene and p-Xylene |
18 |
0.41 |
0.04 |
2.12 |
2,300 |
|
o-Xylene |
18 |
0.16 |
0.02 |
0.86 |
2,300 |
Table 5b. Comparison of Winnipeg and Tilston BTEX
Concentrations
(24-hour samples)
|
Compound
|
Number of Samples
|
Average
(µg/m3)
|
Minimum
(µg/m3)
|
Maximum
(µg/m3)
|
Ontario Air Quality Standard(5)
(µg/m3)
|
|
WINNIPEG(1) - (1990 - 1998)
|
|
Benzene |
501 |
1.89 |
0.39 |
12.00 |
10(6) |
|
Toluene |
500 |
5.98 |
1.26 |
54.40 |
2,000 |
|
Ethyl benzene |
501 |
0.88 |
0.05 |
6.49 |
N/A |
|
m-Xylene and p-Xylene |
501 |
3.28 |
0.01 |
21.20 |
2,300 |
|
o-Xylene |
501 |
1.23 |
0.01 |
9.46 |
2,300 |
|
TILSTON(4)
|
|
Benzene |
42 |
0.57 |
0.20 |
1.90 |
10(6) |
|
Toluene |
42 |
0.75 |
0.20 |
7.23 |
2,000 |
|
Ethyl benzene |
42 |
0.16 |
0.05 |
1.58 |
N/A |
|
m-Xylene and p-Xylene |
42 |
0.43 |
0.08 |
5.82 |
2,300 |
|
o-Xylene |
42 |
0.16 |
0.03 |
2.02 |
2,300 |
(1) Winnipeg:
24-hour samples
(2) Tilston: 1-hour samples
(3) Ontario Point of Impingement Standard (half-hour
average)
(4) Tilston: 24-hour samples
(5) Ontario Ambient Air Quality Criteria (24-hour
average)
(6) Quebec Air Quality Guideline for benzene (24-hour
average)
N/A: not available
Aldehydes and Ketones
Since the start of the monitoring in August 1999, 40 aldehyde
and ketone samples were taken. The levels were comparable to
levels measured in Winnipeg and were less than any of the
available air quality criteria. The air concentrations of the
aldehydes and ketones are summarized in Table 6. Also shown are
any air quality guidelines that are available.
Table 6. Tilston Air Quality - Aldehyde and Ketone
Monitoring Data (µg/m3)
|
Compounds |
Tilston |
Winnipeg |
Ontario Air
Quality
Criteria (µg/m3) |
|
(August 1999 - May 2000) |
(March 1997 - June 1997) |
|
Average |
Min. |
Max. |
Average |
Min. |
Max. |
|
Formaldehyde |
1.11 |
0.51 |
3.68 |
3.19 |
1.58 |
9.09 |
65 |
24-hour |
|
Acetaldehyde |
0.88 |
0.34 |
4.45 |
1.54 |
0.96 |
3.76 |
500 |
24-hour |
|
Acrolein |
0.03 |
0.00 |
0.37 |
0.12 |
0.04 |
0.39 |
24 |
24-hour |
|
Acetone |
2.33 |
0.88 |
5.79 |
4.23 |
2.12 |
8.12 |
48,000 |
24-hour |
|
Propionaldehyde |
0.24 |
0.07 |
1.07 |
0.45 |
0.22 |
0.92 |
3 |
24-hour |
|
Crotonaldehyde |
0.02 |
0.00 |
0.23 |
0.15 |
0.04 |
0.68 |
--- |
--- |
|
Methyl ethyl ketone |
0.47 |
0.18 |
2.25 |
1.51 |
0.60 |
6.53 |
31,000 |
1-hour |
|
Benzaldehyde |
0.02 |
0.00 |
0.15 |
0.23 |
0.10 |
0.69 |
--- |
--- |
|
2-Pentanone/ Isovaleraldehyde |
0.12 |
0.00 |
1.31 |
0.30 |
0.05 |
1.17 |
--- |
--- |
|
Valeraldehyde |
0.03 |
0.00 |
0.18 |
0.16 |
0.00 |
0.46 |
--- |
--- |
|
o-Tolualdehyde |
0.00 |
0.00 |
0.00 |
0.03 |
0.00 |
0.50 |
--- |
--- |
|
m-Tolualdehyde |
0.00 |
0.00 |
0.00 |
0.10 |
0.00 |
0.26 |
--- |
--- |
|
p-Tolualdehyde |
0.00 |
0.00 |
0.00 |
0.02 |
0.00 |
0.11 |
--- |
--- |
|
Methyl isobutyl ketone |
0.01 |
0.00 |
0.12 |
0.22 |
0.00 |
0.99 |
--- |
--- |
|
Hexanal |
0.06 |
0.00 |
0.25 |
0.32 |
0.06 |
1.55 |
--- |
--- |
|
2,5-Dimethyl benzaldehyde |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
--- |
--- |
Wind Speed and Direction
Wind speed and wind direction had been monitored at the Farm
Yard #1 site from July 1998 to March 1999 and at the trailer at
the 6-9 Well Site from early April 1999 to June 2000. Wind roses
showing the average wind speed and direction for these two sites
are shown in Figures 2 and 3. For each direction, the length of
each bar reflects the frequency of wind from that direction and
the width of the components of the bar indicates the wind speed.
For example, in Figure 3, the wind was from the west about 11% of
the time and the maximum wind speed was over 50 km/hr.
Figure 2. Wind Rose - Farm Yard #1 (July 22,
1998 to March 31, 1999)
Figure 3. Wind Rose 8-9 Well Site (April 18,
1999 to June 15, 2000).
Several differences are apparent between the two wind roses; at
the 6-9 Well Site there was a higher frequency of winds from the
south and the north-west sector and a lower frequency of winds
from the north-east sector compared with the Farm Yard #1 site.
These differences may have been due to several factors, including:
i) buildings obstructing the wind flow when the monitor was
located at the Farm Yard #1 site; and ii) a seasonal effect since
different times of the year were monitored at the two sites (i.e.,
late summer through winter at the Farm Yard #1 site compared with
all seasons at the 6-9 Well Site).
In Figure 4, the wind rose plots hydrogen sulphide
concentration against wind direction for the 6-9 Well Site. For
each direction, the length of each bar reflects the frequency of
wind from that direction, while the width of the components
indicates the hydrogen sulphide concentration. The wind was from
the west about 11% of the time and the maximum hydrogen sulphide
concentration was in the range of 36.0 to 40.0 ppb. A similar wind
rose could not be developed for the Farm Yard #2 site because no
wind data were collected at that site.
Figure 4. Tilston hydrogen sulphide wind rose:
wind direction versus hydrogen sulphide concentration at
6-9 well site (May 7, 1999 to June 16, 2000)
Winds that are from the West-South-West through West could
carry emissions from the battery to the 6-9 Well Site. Winds from
the West-North-West through North-West could carry emissions from
the battery to the Farm Yard #2 site.
For most of the monitoring period, the wind monitor used for
the measurement of wind speed and direction had a threshold
sensitivity for wind direction of 1.1 m/s (2.5 mph or 4 km/hr) at
a 10 degree displacement. When the wind speed was 4 km/hr or
lower, the wind may have been unable to move the wind vane
sufficiently to accurately measure the wind direction. A new wind
monitor, installed on March 28, 2000 at the 6-9 Well Site, had a
lower threshold sensitivity (i.e., 0.5 m/s or 1.8
km/hr).
Review of Air Quality in the Tilston Area
From the data collected during this air quality monitoring
program, several conclusions can be made:
i) During the initial monitoring that was undertaken at the
Farm Yard #1 site, sulphur dioxide was detected during a brief,
two-week period in August 1998; on 4 of these occasions, the
provincial ambient air quality objective for sulphur dioxide was
exceeded.
ii) At the two expanded monitoring stations (i.e.,
Farm Yard #2 and 6-9 Well Site), sulphur dioxide was not
detected except for a few occasions of low levels of sulphur
dioxide at the 6-9 Well Site and the Farm Yard #2 site. The
levels measured were all below the provincial air quality
objective.
iii) Hydrogen sulphide was occasionally measured at low
levels, especially at the monitor located at the 6-9 Well Site
east of the 8-8-6-29 W.P.M. battery. On a relatively few
occasions at both monitoring stations, the Manitoba air quality
guideline of 11 ppb was exceeded.
iv) VOC's, including BTEX compounds, were similar or lower
than the levels measured in Winnipeg. For those VOC's which had
air quality guidelines, the levels measured were significantly
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