2.1
In
accordance with the Particular Specification of the Project, ET is required to
conduct 1-hr and 24-hr TSP monitoring at the temporary CWSF in TKO 137 during
the construction and operation periods to ensure the activities in the Project
does not generate dust which exceeds the acceptable level. Appendix C shows the
Action and Limit Levels for the environmental monitoring works.
2.2
High volume sampler (HVS - Model GS-2310 Accu-vol) complete with the appropriate sampling inlets was
installed for 24-hr TSP sampling. The HVS is composed of a motor, a filter
holder, a flow controller and a sampling inlet and its performance
specification complies with USEPA Standard Title 40, Code of Federation
Regulations Chapter 1 (Part 50 Appendix B). A portable dust meter was used for
the 1-hr TSP monitoring. Table 2.1 summarises the equipment used.
Table 2.1 Air Quality Monitoring
Equipment
|
Equipment |
Model |
|
HVS |
GS 2310 Accu-vol system |
|
Calibrator |
GMW 25 |
|
1-hour TSP Dust Meter |
Laser Dust
Monitor – Model LD-3 |
|
Calibrator – Dust Meter |
Rupprecht & Patashnick
TEOM® |
Monitoring Parameter, Frequency and Schedule
2.3
The monitoring parameters and frequency are summarised in
Table 2.2. The monitoring schedule for the reporting period is shown in
Appendix D.
Table 2.2 Frequency of Air
Quality Monitoring
|
Parameters |
Frequency |
|
24-hour TSP |
Once/week |
|
1-hour TSP |
Three times/week |
2.4
The location for the air quality monitoring station TKO2 is
provided in Table 2.3 and depicted in Figure 2.1.
Table 2.3 Air Quality Monitoring
Stations
|
Station
ID |
Identity/Description |
|
TKO2 |
Combined Reception & Exit Office in Area B1 |
24-hour TSP Monitoring
Operating/Analytical Procedures
2.5
Operating/analytical procedures for the
operation of HVS are as follows:
·
The
sampler was placed on a horizontal platform with appropriate supporting
structure such that:
-
no two samplers were placed less than 2 metres apart.
-
the distance between the sampler and an obstacle, such as buildings, was at
least twice the height that the obstacle protrudes above the sampler.
-
a minimum of 2 metres separation from walls, parapets and penthouses was
required for the rooftop samplers.
-
a minimum of 2 metres separation from any supporting structure, measured
horizontally was required.
-
airflow around the sampler was unrestricted.
-
no furnaces or incineration flues were operating near the sampler.
-
the sampler was more than 20 metres from the dripline.
-
Any
wire fence and gate, to protect the sampler, should not cause any obstruction
during monitoring.
·
Prior
to the commencement of the dust sampling, the flow rate of the high volume
sampler was properly set (between 1.1 m3/min. and 1.4 m3/min.)
in accordance with the manufacturer's instruction to within the range
recommended in USEPA Standard Title 40, CFR Part 50.
·
For
TSP sampling, fibreglass filters (G810) were used [Note: these filters have a
collection efficiency of > 99% for particles of 0.3 mm diameter].
·
After
sampling, the filter was transferred from the filter holder of the HVS to a
sealable plastic bag and sent to the laboratory for weighing. The elapsed time
was also recorded.
·
Before
weighing, all filters were conditioned for 24 hours before weighing under
temperature of 25°C ±3°C and the relative humidity (RH) < 50% ±5%,
preferably 40%.
·
All
measurement procedures in section 4.3 to 4.9 of the EM&A Manual were
followed during the reporting period.
Maintenance
2.6
Proper maintenance would be provided for
the HVS:
·
The
HVS motors and their accessories have been properly maintained. Appropriate
maintenance such as routine motor brushes replacement (time interval for
replacement is about 500 hours) and electrical wiring checking have been
conducted to ensure that the equipment and necessary power supply were in good
working condition.
1-hour TSP Monitoring
Measuring
Procedures
2.7
The sampler was placed with appropriate
supporting structure. The requirements of the location of the sampler were the
same as HVS and were presented in Section 2.5 of this report.
2.8
The measuring procedures of the 1-hour dust
meter were in accordance with the Manufacturer’s Instruction Manual as follows:
·
Set
POWER to “ON”, push
·
Push
the knob at MEASURE position.
·
Push
“O-ADJ” button. (Then meter’s indication is 0).
·
Push
the knob at SENSI ADJ position and set the meter’s indication to S value
described on the Test Report using the trimmer for SENSI ADJ.
·
Pull
out the knob and return it to MEASURE position.
·
Push
“START” button.
·
All
measurement procedures in section 4.3 to 4.9 of the approved EM&A Manual were
followed during the impact monitoring period.
Maintenance
2.9
Air suction inlet was normally closed
unless in operation. Regular cleaning of the air suction inlet was provided.
Wind Data
2.10
Historically, the meteorological data for Fill Bank
operations at the site was obtained from the in-situ wind station for TKO 137 under
previous contracts. Therefore, such practice would be maintained to ensure
consistence of meteorological data for the contract in the Fill Bank.
Calibration Details
24-hour TSP Monitoring
2.11
The
HVS was calibrated upon installation on site and prior to commissioning. Subsequent
calibration would be provided at 2-month intervals using GMW-25 Calibration
Kit. The flow rate of the HVS with mass flow controller was calibrated using an
orifice calibrator. Five-point calibration was adopted.
2.12
The HVS was calibrated on 7 September 2007. Calibration
details are provided in Appendix E.
1-hour TSP Monitoring
2.13
The 1-hour TSP meters were checked at 3-month intervals to
confirm normal operation of the equipment and calibrated at 1-year interval
throughout all stages of the air quality impact monitoring.
2.14
The 1-hour TSP meters were
calibrated on 19 June 2007 and the next calibration will be conducted by 19
June 2008.
2.15
In the reporting month, all the 1-hr and 24-hr TSP
monitoring events were carried out in accordance with the schedule.
2.16
The actual monitoring program for October 2007 is presented
in Appendix D. All monitoring data and graphical presentations of the
monitoring results are provided in Appendix F. Table 2.4 lists out three 1-hr
TSP monitoring results and Table 2.5 lists out all the 24-hr TSP monitoring
results.
Table 2.4 Summary of 1-hr TSP
Monitoring Results
|
Date |
TKO2 |
Monitoring Status |
|||
|
1st 1-hr TSP (mg/m3) |
2nd 1-hr TSP (mg/m3) |
3rd 1-hr TSP (mg/m3) |
Exceedance1 |
||
|
06/10 |
101.3 |
100.5 |
102.4 |
X |
Regular |
|
12/10 |
93.0 |
91.5 |
91.0 |
X |
Regular |
|
18/10 |
94.7 |
95.1 |
95.6 |
X |
Regular |
|
24/10 |
97.4 |
95.6 |
94.2 |
X |
Regular |
|
30/10 |
94.1 |
93.2 |
95.5 |
X |
Regular |
1. L – limit level exceedance;
A - action level exceedance;
X – not an exceedance
Table 2.5 Summary of 24-hr TSP
Monitoring Results
|
Date |
TKO2 |
Monitoring Status |
|
|
24-hr TSP (mg/m3) |
Exceedance1 |
||
|
05/10 |
230.6 |
X |
Regular |
|
11/10 |
112.9 |
X |
Regular |
|
17/10 |
134.5 |
X |
Regular |
|
23/10 |
118.9 |
X |
Regular |
|
29/10 |
129.7 |
x |
Regular |
1.
L – limit level exceedance; A -
action level exceedance; X – not an exceedance
2.17
There was no exceedance
of 1-hour and 24-hour TSP monitoring recorded in the reporting month.
2.18
Besides the construction activities
inside the Project site, other potential dust sources included the dump truck
traffic, dumping and manual sorting of inert waste inside the Fill Bank of TKO 137.
2.19
Wind data, including wind speed and wind direction, are
annexed in Appendix G.