Table of Content
1.3 Construction Works undertaken during the Reporting Month
1.4 Summary of EM&A Requirements
2.4 Monitoring Parameters, Frequency and Duration
2.5 Monitoring Procedures and Calibration Details
3.4 Monitoring Parameters, Frequency and Duration
3.5 Monitoring Procedures and Calibration Details
4.4 Monitoring Parameters, Frequency and Duration
4.5 Monitoring Procedures and Calibration Details
5.1 Review of Environmental Monitoring Procedures
5.2 Assessment of Environmental Monitoring Results
5.4 Status of Environmental Licensing and Permitting
5.5 Implementation Status of Environmental Mitigation Measures
5.6 Implementation Status of Action/Limit Plans
5.7 Implementation Status of Environmental Complaint Handling Procedures
6.1 Status of Natural Gas supply
6.2 Key Issues for the Coming Month
6.3 Monitoring Schedules for the Next 3 Months
6.4 Construction Program for the Next 3 Months
List of Tables
Table 1.1 Construction
Activities and Their Corresponding Environmental Mitigation Measures
Table 2.1 Air Quality Monitoring Locations
Table 2.2 Air Quality Monitoring Equipment
Table 2.3 Air Quality Monitoring Parameter, Duration and Frequency
Table 3.1 Noise
Monitoring Locations
Table 3.2 Noise
Monitoring Equipment
Table 3.3 Noise
Monitoring Duration and Parameter
Table 4.1 Water Quality Monitoring Locations
Table 4.2 Water Quality Monitoring Equipment
Table 4.3 Water Quality Monitoring Parameters and Frequency
Table 4.4 Laboratory Analysis Methodologies of Marine
Water Samples
Table 5.1 Summary
of AL Level Exceedances on Monitoring Parameters
Table 5.2 Estimated
Amounts of Waste Generated in March 2002
Table 5.3 Summary
of Environmental Licensing
and Permit Status
Table
5.4 Environmental
Complaints / Enquiries Received in March 2002
Table
5.5 Outstanding
Environmental Complaints / Enquiries Received Before
List of figures
Figure
1.1 Layout
of Work Site
Figure
1.2 Cable
Route of Transmission System
Figure
2.1 Location
of Air Quality Monitoring Stations
Figure
3.1 Location
of Noise Monitoring Stations
Figure
3.2 Locations
of Manual Noise Monitoring
Figure
4.1 Location
of Water Quality Monitoring Stations
Appendices
Appendix B Action and Limit Levels for Air Quality, Noise, Water quality Monitoring
Appendix C Environmental
Monitoring Schedule
Appendix D Air
Quality Monitoring Results for March 2002
Appendix E Noise
Monitoring Results for March 2002
Appendix F Water
Quality Monitoring Results for March 2002
This is the twelfth monthly Environmental Monitoring and Audit (EM&A)
report for the Project “Construction of Lamma Power Station Extension” prepared
by the Environmental Team (ET).
This report presents the results of impact monitoring on air quality, noise and marine water quality for the said project in March 2002.
Air, noise and water quality
monitoring were performed. The results were checked
against the established
Action/Limit (AL) levels.
An on-site audit was conducted once per week. The implementation status of the environmental
mitigation measures, Event/Action
Plan and environmental complaint handling procedures were also checked.
Construction
Activities Undertaken
Construction
activities for site formation during the reporting month were placing of drainage layer and rockfill, seawall construction, sand filling, and piling of foundation for link
bridge.
Construction of
transmission system commenced in March 2002. The construction activity in the
month was erection of hoarding.
Environmental
Monitoring Works
All monitoring work at designated stations was performed
as scheduled in the reporting period.
Air Quality
No exceedance
of Action and Limit levels for air
quality was recorded in the
month.
Noise
Construction work for Lamma Extension was carried out during the
restricted hours including evening-time, holidays and night-time
under valid Construction Noise Permits. No exceedance of Action and Limit levels for noise arising from the construction of Lamma
Extension and Transmission System was recorded in the month.
Water Quality
There was one (1) case of Action Level exceedance
and one (1) case of Limit Level exceedance for water quality in the reporting
month. Both cases of action/limit
level exceedance were contributed by SS.
For these exceedances, comprehensive investigations have been carried
out. It was found that no
noticeable sediment plume migration from the direction of the site to the
sampling location was observed.
Hence, the exceedances were considered not related to site activities
and have been explained to the satisfaction of EPD. No further action was required.
Site Environmental Audit
Site audits
were carried out on a weekly basis to monitor environmental issues on the construction site. The site conditions were generally
satisfactory. All required mitigation
measures were implemented.
Environmental Licensing and Permitting
Description |
Permit No. |
Valid Period |
Issued To |
Date of Issuance |
|
From |
To |
||||
Varied Environmental Permit |
EP-071/2000/B |
13/07/01 |
- |
HEC |
13/07/01 |
Construction Noise Permit |
GW-UW0522-01 |
16/01/02 |
11/07/02 |
Contractor |
16/01/02 |
Construction Noise Permit |
GW-UW0036-02 |
06/03/02 |
31/08/02 |
Contractor |
06/03/02 |
Dumping Permit |
EP/MD/02-073 |
07/10/01 |
06/04/02 |
Contractor |
05/10/01 |
Implementation
Status of Environmental Mitigation Measures
Environmental
mitigation measures for the construction activities
as recommended
in the EM&A manual were implemented in the reporting month.
Environmental
Complaints
One
complaint against excessive noise emission from the construction activities was
received via EPD in the reporting month.
Though the case could
not be justified, EPD had reminded HEC to pay attention to the construction
work to avoid complaints and HEC had followed up with the contractors
accordingly.
Future Key
Issues
The future key issues to be
considered in the coming month are as follows:
Site Formation
-
to continue monitoring the noise level during construction and to
ensure compliance with the CNP’s already obtained;
-
to continue the preventive measures for noise exceedance and keep
monitoring/ reviewing the performance;
-
to keep reviewing the
monitoring results in order to take corresponding action to ensure the sea
water quality;
-
to provide routine
inspection and necessary maintenance for the silt curtain;
-
to install silt curtain at
the temporary opening between the constructed seawalls, which protrude above the
seawater surface, when the sand filling for the platform shall take place
behind it;
-
to provide de-silting
utilities for wastewater before being discharged from the bored piling works;
Transmission System
-
to ensure that
all excavated materials and debris are covered by debris shelter or sprayed
with water;
-
to continue monitoring the noise level during construction;
-
to continue the preventive
measures for noise exceedance and keep monitoring/ reviewing the performance;
-
to erect hoarding along the
boundary of construction sites before the commencement of civil work;
-
to closely monitor the construction
activities in order to avoid disturbance to the rare plants;
-
to provide temporary fire
fighting equipment for prevention of fire within the work sites.
Concluding Remarks
The
environmental performance of the project was generally satisfactory.
The Environmental Team (hereinafter called the “ET”) was formed within the Hongkong Electric Co. Ltd (HEC) to undertake Environmental Monitoring and Audit for “Construction of Lamma Power Station Extension” (hereinafter called the “Project”). Under the requirements of Section 6 of Environmental Permit EP-071/2000/B, an EM&A programme for impact environmental monitoring set out in the EM&A Manual (Construction Phase) is required to be implemented. In accordance with the EM&A Manual, environmental monitoring of air quality, noise and water quality and regular environmental audits are required for the Project.
The Project involves the construction of a gas-fired power station
employing combined cycled gas turbine technology, forming an extension to the
existing Lamma Power Station. The
key elements of the Project including the construction activities associated
with the transmission system and submarine gas pipeline are outlined as
follows.
· dredging and reclamation to form approximately 22 hectares of usable area;
· construction of six 300MW class gas-fired combined cycle units;
· construction of a gas receiving station;
· construction of a new transmission system linking the Lamma Extension to load centres on Hong Kong Island;
· laying of a gas pipeline for the supply of natural gas to the new power station
This report summarizes the
environmental monitoring and audit work for the Project for the month of March 2002.
An
Environmental Management Committee (EMC) has been set up in HEC to oversee the
Project. The management structure
includes the following:
· Environmental Protection Department (The Authority);
· Environmental Manager (The Chairman of the Environmental Management Committee);
· Engineer;
· Independent Environmental Checker (IEC);
· Environmental Team (ET);
· Contractor.
The project organisation chart for the construction EM&A programme is shown in Appendix A.
1.3
Construction Works undertaken during the Reporting
Month
Construction activities for site formation undertaken during the reporting month were placing of drainage
layer, rock fill, construction of seawall, sand filling, piling of foundation
for link bridge and construction of transmission system. Layout plans for site formation and transmission
system are shown in Figure 1.1
and Figure 1.2 respectively.
The main construction activities carried out during the reporting month and the corresponding environmental mitigation measures are summarized in Table 1.1. The implementation of major mitigation measures in the month is provided in Appendix J.
Table 1.1 Construction Activities and Their Corresponding Environmental Mitigation Measures
Item |
Construction
Activities |
Environmental Mitigation Measures |
Site Formation |
||
1 |
Placing of Drainage Layer and Rockfill, Seawall Construction & Sandfilling |
Water Quality
- Silt curtain installed on the eastern, southern and north western sides of the site; Noise
-
General noise mitigation measures employed at all
work sites throughout the construction phase. Waste Management
-
Waste Management Plan submitted and implemented. Marine Ecology
-
All construction related vessels approached
the site from the designated route/channel to avoid possible disturbance
to the finless porpoise. |
2 |
Piling Foundation for Link Bridge |
Water Quality
- De-silting system installed to treat the wastewater before being discharged. Noise
- General noise mitigation measures implemented and silenced type equipment deployed. Air
- Dust suppression measures implemented. |
Construction of Transmission System
|
||
3 |
Erection of Hoarding |
Water Quality
- Debris & excavated materials covered by debris shelter. Noise
- General noise mitigation measures employed at all work sites throughout the construction phase. Terrestrial Ecology
- Special care and close monitoring to avoid disturbances to the rare plant species. - Temporary fire fighting equipments provided within the work area during construction. |
1.4 Summary of EM&A Requirements
The EM&A program requires environmental monitoring for
air, noise and water
quality. Regular environmental site audits for air quality, noise, water
quality and waste management were
carried out. The detailed EM&A monitoring
work for air quality, noise
and water quality are described in Sections 2, 3 and 4
respectively.
The
following environmental audits are summarized in Section 5 of this report:
· Environmental monitoring results;
· Waste Management Records;
· Weekly site audit results;
· The status of environmental licensing and permits for the Project;
· The implementation status of environmental protection and pollution control/ mitigation measures.
Future key issues will be reported in Section 6 of this report.
1-hour and 24-hour TSP monitoring at agreed frequencies were conducted to monitor air
quality. The impact
monitoring data were checked against the Action/Limit Levels as determined in the Baseline Monitoring
Report (Construction Phase). Appendix B
shows the established Action/Limit Levels for Air Quality.
Three
dust monitoring locations were selected for 1-hour TSP sampling (AM1, AM2 &
AM3) while four monitoring locations were selected for 24-hour TSP sampling
(AM1, AM2, AM3 and AM4). Table 2.1 tabulates the monitoring stations. The locations of the monitoring
stations are shown in Figure 2.1.
Table 2.1 Air Quality Monitoring Locations
Location I.D. |
Description |
AM1 |
Reservoir |
AM2 |
East Gate |
AM3 |
Ash Lagoon |
AM4 |
Tai Yuen Village |
Continuous
24-hour TSP air quality monitoring was performed using the GS2310 High Volume
Air Samplers (HVAS), Partisol Model 2000 Sampler and the MINIVOL Portable
Sampler at AM1&2, AM3 and AM4 respectively. TEOM Model 1400a continuous dust monitors were used to carry
out 1-hour TSP monitoring at AM1, AM2 and AM3. Table 2.2 summarises the equipment used
in dust monitoring.
Table 2.2 Air Quality Monitoring
Equipment
Equipment |
Model and Make |
24-hour
sampling: HVAS
Sampler Partisol
Air Sampler MINIVOL
Portable Sampler 1-hour
sampling: Continuous
TSP Dust Meter |
Model GS2310 Anderson Instruments Inc. Partisol Model 2000 Rupprecht & Patashnick AIRMETRICS TEOM Model 1400a Rupprecht & Patashnick |
2.4
Monitoring
Parameters, Frequency and Duration
Table 2.3 summarises the monitoring parameters, duration and
frequency of air quality monitoring.
The monitoring schedule for the reporting month is shown in Appendix C.
Table 2.3 Air Quality Monitoring Parameter,
Duration and Frequency
Monitoring Stations |
Parameter |
Duration |
Frequency |
AM1 |
1-hour TSP |
1 |
3 hourly samples every 6
days |
24-hour TSP |
24 |
Once every 6 days |
|
AM2 |
1-hour TSP |
1 |
3 hourly samples every 6
days |
24-hour TSP |
24 |
Once every 6 days |
|
AM3 |
1-hour TSP |
1 |
3 hourly samples every 6
days |
24-hour TSP |
24 |
Once every 6 days |
|
AM4 |
24-hour TSP |
24 |
Once every 6 days |
2.5
Monitoring
Procedures and Calibration Details
24- hour TSP Monitor:
Preparation of
Filter Papers
· Visual inspection of filter papers was carried out to ensure that there were no pinholes, tears and creases;
· The filter papers were then labelled before sampling.
· The filter papers were equilibrated at room temperature and relative humidity < 50% for at least 24 hours before weighing.
Field Monitoring
· During collection of the sampled filter paper, the information on the elapse timer was logged. Site observations around the monitoring stations, which might have affected the monitoring results, were also recorded. Major pollution sources, if any, would be identified and reported. The flow record chart for the previous sampling was checked to see if there was any abnormality.
· The post-sampling filter papers were removed carefully from the filter holder and folded to avoid loss of fibres or dust particles from the filter papers;
· The filter holder and its surrounding were cleaned;
· A pre-weighed blank filter paper for the next sampling was put in place and aligned carefully. The filter holder was then tightened firmly to avoid leakage;
· A new flow record chart was loaded into the flow recorder;
· The programmable timer was set for the next 24 hrs sampling period, ! 1/2 hr;
·
The post-sampling filter papers were equilibrated at
room temperature and relative humidity < 50% for at least 24 hours before
weighing.
1- hour TSP Monitor:
· The following parameters of the TEOM model dust meters are regularly checked to ensure proper functionality:
o Mass concentration;
o Total mass;
o Frequency of the tapered element;
o Electrical noise;
o Main flow;
o Auxiliary flow.
Maintenance
& Calibration
· The monitoring equipment and their accessories are maintained in good working conditions.
· Monitoring equipment is calibrated at monthly intervals. Calibration details are shown in Appendix G.
Dust monitoring was conducted as scheduled in the reporting month. All
monitoring data and graphical presentation of the monitoring results are
provided in Appendix D. Key findings and observations are provided below:
1-hour TSP
No
exceedance of 1-hour TSP Action/Limit Level was recorded in the month.
24-hour TSP
No
exceedance of 24-hour TSP Action/Limit Level was recorded in the month.
Continuous noise alarm monitoring at Ash Lagoon/Ching Lam were carried out to calculate the noise contributed by the construction activities at the two critical NSR’s, viz. Long Tsai Tsuen/Hung Shing Ye and the school within the village of Tai Wan San Tsuen. The impact monitoring data for construction noise other than percussive piling were checked against the limit levels specified in the EM&A Manual. With the availability of the construction noise permits, impact monitoring for the construction work during the restricted hours was also carried out. Section 5 presents the details of the construction noise permits.
With the
commencement of construction work for the transmission system in March 2002,
manual noise measurement at the Pak Kok Tsui residences was carried out for the
reporting month. The impact noise
monitoring data were checked against the limit levels specified in the
EM&A Manual. Appendix B shows the established Action/Limit
Levels for noise.
In accordance with the EM&A manual, the identified noise monitoring locations are listed in Table 3.1 and shown in Figure 3.1 and Figure 3.2.
Table
3.1 Noise Monitoring
Locations
Purpose of noise monitoring |
Monitoring Location |
Lamma Extension |
Ash Lagoon |
Lamma Extension |
Ching Lam |
Construction of Transmission System |
Pak Kok Tsui
residences (No.2 and No.8) |
The sound level meters used for noise monitoring complied with International Electrotechnical Commission Publications 651:1979 (Type 1) and 804:1985 (Type 1). The noise monitoring equipment used is shown in Table 3.2.
Table 3.2 Noise Monitoring Equipment
Equipment |
Model |
|
Lamma
Extension |
Construction
of Transmission System |
|
Sound
level meter |
Rion NA-27 |
Rion NL-14 |
Sound level calibrator |
Rion NC-74 |
B&K
4231 |
3.4 Monitoring Parameters, Frequency and Duration
Continuous alarm monitoring of A-weighted Leq levels was
carried out at Ash Lagoon and Ching Lam while manual noise monitoring was
conducted at Pak Kok Tsui residences.
The manual noise
monitoring schedule for the reporting month is shown in Appendix
C. The measurement duration and parameter of noise monitoring were
presented in Table 3.3 as follows:
Table 3.3 Noise Monitoring Duration and
Parameter
Location |
Time Period |
Frequency |
Parameter |
Ash Lagoon Ching Lam |
Daytime: 0700-1900
hrs on normal weekdays Evening-time
& holidays: 0700-2300 hrs on holidays; and 1900-2300 hrs on all other days Night-time: 2300-0700 hrs of next
day |
Daytime: 30 minutes Evening-time
& holidays: 5 minutes Night-time: 5 minutes |
30-min
LAeq 5-min
LAeq 5-min
LAeq |
Pak Kok Tsui residences |
0700-1900 hrs on normal weekdays |
Twice per week |
30-min
LAeq |
3.5
Monitoring Procedures and
Calibration Details
Monitoring Procedures
Continuous Noise Monitoring for Lamma Extension
Construction
The measured noise
levels (MNL's) were collected at the noise alarm monitoring
stations at Ash Lagoon and Ching Lam. The notional
background noise levels (viz. baseline noise data at
Ash Lagoon and Ching Lam) were applied to correct the
corresponding MNL's in
30-min/5-min LAeq.
A wind speed sensor was installed at Station Building Rooftop. The wind speed signal was used to determine whether the
data from Ash Lagoon and Ching Lam noise alarm monitoring stations were affected. The instantaneous data was discarded in case the
instantaneous wind speed exceeded
10 m/s. The 30-min/5-min LAeq was
considered valid only if the amount of valid data was equal to or above 70%.
When
calibrating the noise measuring equipment, all
observations around the monitoring stations, which might have affected
the monitoring results, were recorded.
Manual Noise Monitoring for Transmission System
Construction
Manual noise monitoring was carried out at the Pak Kok Tsui residences in accordance with standard acoustical principles and practices for checking the impact of noise related to construction of the Transmission System.
Hand‑held
anemometer was used to measure the wind speed while taking noise measurements.
If the wind speed is excessive,
noise data will be discarded and re-measured.
Equipment Calibration
The sound level meters and calibrators have been verified by the manufacturer or accredited laboratory. Equipment for continuous noise monitoring was calibrated at site on a monthly basis.
The sound level meters used for manual noise
measurement were calibrated
with a sound level calibrator immediately before and after noise measurement in
accordance with the relevant Technical Memoranda under the Noise Control
Ordinance. Calibration details are shown in Appendix G.
Continuous noise monitoring was conducted at the two monitoring
stations at Ash Lagoon and Ching Lam while manual noise monitoring was carried
out at the Pak Kok Tsui residences.
All monitoring results and their graphical presentations are provided in Appendix E.
No
exceedance of noise Action/Limit Level was recorded in the month.
Marine
water quality monitoring at the monitoring locations adjacent to the
construction site was carried out by a monitoring consultant, HKPC. The purpose was to ensure that
deterioration of water quality, if any, would be detected and that timely
action could be taken to rectify the situation. The impact monitoring data were checked against the AL levels set out in the
Baseline Monitoring Report (Construction Phase).
As there were no activities for the laying of the gas pipeline in the
reporting month, no water quality impact monitoring at the relevant stations
was carried out.
A total of 12 water quality monitoring locations were selected. 7 Sensitive Receiver
(SR) stations were chosen on the basis of their proximity to the construction
site, 5 Marine Control
stations (C) as recommended in the EIA were selected to facilitate
comparison of the water quality of the SR stations with ambient water quality
conditions. Table 4.1 describes
the locations of these monitoring stations. Their locations are shown in Figure 4.1.
Table 4.1 Water Quality Monitoring Locations
Type |
Monitoring Location |
HK Metric Grid E |
HK Metric Grid N |
Sensitive Receiver
Stations |
SR1 |
830 224 |
811 528 |
SR2 |
829 004 |
810 903 |
|
SR3 |
829 194 (829 166)1 |
808 600 (808 592)1 |
|
SR4 |
830 119 |
808 650 |
|
SR5 |
830 386 |
807 189 |
|
SR6 |
829 977 |
805 758 |
|
SR7 |
829 566 |
804 545 |
|
Marine Control Stations |
C1 |
830 542 |
813 492 |
C2 |
828 608 |
813 492 |
|
C3 |
826 776 |
809 978 |
|
C4 |
826 776 |
806 464 |
|
C5 |
830 440 |
802 186 |
1. Due to the construction programme, the
monitoring location SR3 was slightly shifted since the monitoring on 16th
April 2001. EPD has verbally been
informed of the shift of the monitoring location.
Table 4.2 summarizes the equipment used in the water-quality monitoring programme.
Table 4.2 Water Quality Monitoring Equipment
Equipment |
Detection
Limit |
YSI 6820 Water Quality Monitor |
Temperature: -5 to 50 0C; +/- 0.15 0C Salinity: 0 to 70 ppt; +/- 0.2 ppt Dissolved Oxygen: 0 to 200%; +/- 0.5% 0 to 20 mg/L; +/- 0.2 mg/L Turbidity: 0 to 100 and 100 to 1000 NTU; +/- 5%
of the range |
Trimble NT200 GPS |
Accuracy better than 3m |
Leica GS5 |
Accuracy better than 3m |
4.4
Monitoring
Parameters, Frequency and Duration
Table 4.3
summarizes the monitoring parameters, frequencies and total duration of water
quality monitoring. The monitoring schedule for reporting month is shown in Appendix C.
Table 4.3 Water Quality Monitoring Parameters and Frequency
Monitoring Stations |
Parameters |
Frequency |
No. of Depths |
No. of Samples |
Sensitive Receiver Stations SR1, SR2,
SR4, SR5, SR6 & SR7 Marine Control Stations C1, C2,
C3, C4 & C5 |
· Depth, m · Temperature, oC · Salinity, ppt · DO, mg/L · DO Saturation, % · Turbidity, NTU · SS, mg/L · pH |
3 Surface, Mid-Depth
and Bottom |
2 Mid-ebb
and Mid-flood |
For
laboratory analysis of marine water samples collected at SR3, only SS parameter
was measured.
4.5
Monitoring
Procedures and Calibration Details
Monitoring
Procedures
· The monitoring stations were accessed using survey boat to within 3m, guided by Differential Global Positioning System (DGPS).
· The depth of the monitoring location was measured using depth meter in order to determine the sampling depths. Afterwards, the water sampler was lowered into the water to the required depths of sampling. Upon reaching the pre-determined depth, a messenger to activate the sampler was then released to travel down the wire. The water sample was sealed within the sampler before retrieving.
· All in-situ measurements at each monitoring stations were taken at 3 water depths, where appropriate, namely 1m below water surface, mid-depth, and 1 meter from seabed, except where the water depth was less than 6m, the mid-depth measurement was omitted. If the water depth was less than 3m, only the mid-depth position was monitored.
· At each measurement/sampling depth, two consecutive measurements were taken. The probes were retrieved out of the water after the first measurement and then redeployed for the second measurement. Where the difference in the value between the first and the second readings of each set was more than 25% of the value of the first reading, the reading was discarded and further samplings were taken.
· The duplicate water samples for physical and chemical analysis were stored into a pre-labelled high-density polyethylene (HDPE) bottle pre-rinsed with the same water samples. The sample bottles were than packed in a cool-box (cooled to 4oC without being frozen) and delivered to a HOKLAS Laboratory for analysis upon the completion of each round of sampling.
· In addition, field information such as the general meteorological conditions and any observations regarding any significant activities in the vicinity of each monitoring location were also recorded. Major water pollution sources, if any, were identified and recorded.
Equipment
Calibration
The equipment
deployed for in-situ measurement of marine water quality was calibrated before
use. The methodologies for the
calibration follow the instruction manuals provided by the corresponding manufacturers. The calibration records are shown in Appendix G.
Laboratory Analysis & QA/QC
The collected marine water samples were analyzed for Suspended Solids with methodologies summarized in Table 4.4.
Table 4.4 Laboratory
Analysis Methodologies of Marine Water Samples
Parameter |
Method |
Limit of Reporting
(mg/L) |
Suspended Solids |
APHA 17 ed 2540 D |
1.0 |
In order to ensure that the laboratory analysis works were carried out properly, stringent QA/QC procedures (which includes the sample preparation as well as the subsequent instrumentation analysis) were followed. According to the requirements stipulated in the EM&A Manual, QA/QC requirements for laboratory testing include:
1) "Blind" duplicate samples analysis of 10% collected marine water samples; and
2) in-house QA/QC procedures of the testing laboratory (this includes the use of blank, batch duplicates and quality control samples).
Blind Duplicate:
In order to cross check the precision of the measurement results obtained from the laboratory analysis, “blind” duplicate samples of 10% of the collected marine water samples were analysed alongside the normal samples. The sample codes for the “blind” duplicates were determined by the sampling team and are not identifiable by the laboratory. The results of the “blind” duplicate samples are summarized in Appendix G.
In accordance with the QA/QC procedures of Environmental Management Laboratory of HKPC, QA/QC procedures were conducted for at least 5% of samples. A total of 936 sets of samples (for Suspended Solids analysis) were received during the marine monitoring period including both ebb and flood tides. Therefore at least 5% laboratory blanks, batch duplicates, quality control samples and recovery tests for each parameter were conducted. The acceptance criteria are outlined in each type of Quality Control data.
Blank:
A laboratory blank is an analyte free matrix to which all reagents are added in the same volumes or proportions as used in the standard sample preparation to monitor contamination introduced in laboratory. The acceptance criterion for laboratory blank in Environmental Management Division (EMD) Laboratory of HKPC stipulated in EMD Quality Manual is less than the detection limit. All the laboratory blank values and acceptance criterion of suspended solids are summarized in Appendix G.
Batch Duplicate:
Batch duplicate is an intra-laboratory split sample randomly selected from the sample batch to monitor the method precision in a given matrix. The acceptance limit of duplicate values of suspended solids and their duplicate results are summarized in Appendix G.
Quality Control Sample:
The quality control sample is the analysis of a material with a known concentration of contaminants to determine the accuracy of results in a given matrix. The quality control samples results for suspended solids are shown in Appendix G.
The QA/QC results in Appendix G indicated that the laboratory analysis works of the collected marine water samples were properly carried out and the measurement results obtained were valid in accordance with the Hong Kong Laboratory Accreditation Scheme (HOKLAS) requirements. On the other hand, the “blind” duplicate measurement results indicated that the precision of the measurements for Suspended Solids are in compliance with the HOKLAS requirements.
Marine water monitoring was conducted as scheduled in the reporting month. All monitoring data and graphical
presentation of the monitoring results are provided in Appendix F. Key findings and observations are provided
in the following table:
Summary of Exceedances in Suspended Solids
(Depth Average) in March 2002
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
1st March |
0 |
0 |
N. A. |
4th March |
0 |
1 SR2 during flood tide |
Not related to site activities. Based on the
observation made by the sampling team, there was no noticeable sediment plume
migrating from the direction of the site to the sampling location. Besides,
the measurement results at SR2 during the PM session of the same sampling day
were below the action level. Therefore, the said exceedance might be due to
background fluctuation |
6th March |
0 |
0 |
N. A. |
8th March |
0 |
0 |
N. A. |
11th March |
0 |
0 |
N. A. |
13h March |
0 |
0 |
N. A. |
15th March |
0 |
0 |
N. A. |
18th March |
0 |
0 |
N. A. |
20th March |
0 |
0 |
N. A. |
22nd March |
1 SR6 during ebb tide |
0 |
Not related to site activities. Based on the
observation made by the sampling team, there was no noticeable sediment plume
migrating from the direction of the site to the sampling location. Besides,
the measurement result at SR3 (which is much closer to the site as compared
with SR6) was much below the corresponding Action Level of SR6. Therefore,
the said exceedance might be due to background fluctuation. |
25th March |
0 |
0 |
N. A. |
27th March |
0 |
0 |
N. A. |
29th March |
0 |
0 |
N. A. |
There was
one (1) case of Action Level exceedance and one (1) case of Limit Level
exceedance for water quality in the reporting month. Both cases of action/limit level exceedance were contributed
by SS. For these exceedances,
comprehensive investigations have been carried out. It was found that no noticeable sediment plume migration
from the direction of the site to the sampling location was observed. Hence, the exceedances were considered
not related to site activities and have been explained to the satisfaction of
EPD. No further action was required. Nevertheless, EPD, IEC and the
construction contractor have been informed of the exceedances accordingly as
per the requirements of the EM&A Manual.
Figure 4.1 Location of Water Quality Monitoring Stations
5.1
Review of Environmental Monitoring Procedures
The environmental
monitoring procedures were regularly reviewed by the Environmental Team. No modification to the existing monitoring procedures was recommended.
5.2
Assessment
of Environmental Monitoring Results
Monitoring results for Air Quality, Noise and Water Quality
The environmental monitoring results for Air Quality, Noise and Water Quality in the reporting month presented in sections 2,3 and 4 respectively are summarized in Table 5.1.
Table 5.1 Summary of AL Level Exceedances on Monitoring
Parameters
Item |
Parameter
Monitored |
Monitoring
Period |
No. of Exceedances In |
Event/Action
Plan Implementation Status and Results |
||
Action
Level |
Limit Level |
|||||
Air |
||||||
1 |
Ambient TSP (24-hour) |
01/03/02-31/03/02 |
0 |
0 |
|
|
2 |
Ambient TSP (1-hour) |
01/03/02-31/03/02 |
0 |
0 |
|
|
Noise |
||||||
1 |
Noise level at the critical NSR’s predicted by the noise alarm monitoring system |
01/03/02-31/03/02 |
0 |
0 |
|
|
2 |
Manual noise monitoring at the Pak Kok Tsui residences |
01/03/02-31/03/02 |
0 |
0 |
Construction of transmission system commenced in March 2002. |
|
Water |
||||||
1 |
DO (Surface & Middle) |
01/03/02-31/03/02 |
0 |
0 |
|
|
2 |
DO (Bottom) |
01/03/02-31/03/02 |
0 |
0 |
|
|
3 |
SS |
01/03/02-31/03/02 |
1 |
1 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
4 |
Turbidity |
01/03/02-31/03/02 |
0 |
0 |
|
|
Waste
Management Records
The estimated amounts of different types of waste
generated in March 2002 are shown in Table 5.2.
Table
5.2 Estimated Amounts of Waste
Generated in March 2002
Waste Type |
Examples |
Estimated
Amount (m3) |
Dredged Materials |
Marine Mud |
|
Construction Waste |
Concrete Waste, Used formwork |
0 |
Excavated Materials |
Rock and soil |
0 |
General Refuse |
Domestic wastes collected on site |
2 |
Site audits were
carried out by ET on a weekly basis to monitor environmental issues at the construction sites
to ensure that all mitigation measures were implemented timely and properly. The site
conditions were generally satisfactory.
All required mitigation measures were implemented. The weekly site
inspection results are
attached in Appendix I.
5.4 Status of Environmental Licensing and Permitting
All permits/licenses obtained for
the project are summarised in Table 5.3.
Table 5.3 Summary of Environmental Licensing and Permit Status
Description |
Permit No. |
Valid Period |
highlights |
Status |
|
From |
To |
||||
Varied Environmental Permit |
EP-071/2000/B |
13/07/01 |
- |
The whole construction work site. |
Valid |
Construction Noise Permit |
GW-UW0522-01 |
16/01/02 |
11/07/02 |
11 groups (A-K) of PME’s are assigned.
Only one group can be used. Group J and K shall not be operated
between 23:00 and 07:00 on next day. |
Valid. |
Construction Noise Permit |
GW-UW0036-02 |
06/03/02 |
31/08/02 |
Operation of specified PME’s allowed during the restricted hours (07:00-23:00 on holidays and
19:00-23:00 on all other days) |
Valid. |
Dumping Permit |
EP/MD/02-073 |
07/10/01 |
06/04/02 |
Dumping at South Cheung Chau Disposal Area (Relocation of the Spoil Disposal
Areas with effective 29th October 2001) |
Valid |
5.5
Implementation Status of Environmental Mitigation
Measures
Mitigation measures detailed in the permits and the EM&A Manual (Construction
Phase) are required to be implemented. An updated summary of the Environmental Mitigation Implementation Schedule (EMIS) is
presented in Appendix J.
5.6 Implementation Status of Action/Limit Plans
The Action/Event Plans for air quality, noise and water quality extracted from the EM&A Manual (Construction Phase) and the review report on marine water quality monitoring are presented in Appendix H.
As all the action/limit level exceedances were not related to the construction work, no further action can be devised. Nevertheless, EPD, IEC and the construction contractor have been informed of the exceedances accordingly as per the requirements in the EM&A Manual.
5.7 Implementation Status of Environmental Complaint Handling Procedures
In March 2002, one complaint against the construction activities was received via EPD, which was summarized in the Table 5.4 below.
Table 5.4 Environmental
Complaints / Enquiries Received in March 2002
Case Reference / Date, Time Received / Date, Time Concerned |
Descriptions /Actions Taken |
Conclusion / Status |
Case no: 20020301 Received: Verbally via EPD on 25-Mar-02 (p.m.) Concerned: "At mid-night" (exact date not specified) |
EPD informed HEC (during their site visit
to the Lamma Power Station on 25-Mar-02) that they had received a complaint
against excessive noise emission from the area around Lamma Extension at
mid-night. EPD stated that they
had already carried out investigation and found no violation of the relevant
legislations and had closed the case.
EPD reminded HEC to pay attention to the construction work to avoid
complaints. HEC had followed up
with the contractors accordingly. |
The case could not be justified and was closed on the same day
(25-Mar-02). |
Table 5.5 Outstanding
Environmental Complaints / Enquiries Received Before
Case Reference / Date, Time Received / Date, Time Concerned |
Descriptions /Actions Taken |
Conclusion / Status |
Nil |
N/A |
N/A |
6.1
Status
of Natural Gas supply
Based on current project schedule, HEC anticipates there is no delay in the supply of natural gas.
6.2 Key Issues for the Coming Month
Key issues to be considered in the coming month include:
Site
Formation
Noise Impact
· To continue monitoring the noise level during construction and to ensure compliance with the CNP’s already obtained.
· To continue the preventive measures for noise exceedance and keep monitoring/ reviewing the performance.
Water Impact
· To keep reviewing the monitoring results in order to take corresponding action to ensure the sea water quality.
· To provide routine inspection and necessary maintenance for the silt curtain.
· To install silt curtain at the temporary opening between the constructed seawalls, which protrude above the seawater surface, when the sand filling for the platform shall take place behind it.
· To provide de-silting utilities for wastewater before being discharged from the bored piling works.
Transmission
System
Air Impact
· To ensure that all excavated materials and debris are covered by debris shelter or sprayed with water.
Noise Impact
· To continue monitoring the noise level during construction;
· To continue the preventive measures for noise exceedance and keep monitoring/ reviewing the performance.
Terrestrial Ecology Impact
· To erect hoarding along the boundary of construction sites before the commencement of civil work.
· To closely monitor the construction activities in order to avoid disturbance to the rare plants;
· To provide temporary fire fighting equipment for prevention of fire within the work sites.
6.3 Monitoring Schedules for the Next 3 Months
The tentative environmental monitoring schedules for the next 3 months are shown in Appendix C.
6.4 Construction Program for the Next 3 Months
The tentative construction program for the next 3 months is shown in Appendix K.
Environmental monitoring and site inspection were performed as scheduled in the reporting month. All monitoring results were checked and reviewed.
No Action/Limit level exceedance on 1-hour and 24-hour TSP level was recorded in the reporting month.
No
Action/Limit level exceedance on noise was recorded in the reporting month.
Two (2) cases of action/limit level
exceedance on water quality parameters were
recorded in the reporting
month.
As the
action/limit level exceedances were not related to construction activities, no further action is required.
Environmental mitigation measures recommended in the EM&A manual for the construction activities were implemented in the reporting month. One complaint against excessive noise emission from the construction activities was received via EPD in the reporting month. The complaint, however, could not be justified. No prosecution was received for this Project in the reporting period.
The environmental performance of the Project was generally
satisfactory.