Figure 1.1 Layout of Work Site
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 November 2001
Table 5.3 Summary of
Environmental Licensing and Permit Status
Table 5.4 Environmental Complaints / Enquiries Received In November 2001
Table 5.5 Outstanding Environmental Complaints / Enquiries Received Before
List of figures
Figure
1.1 Layout
of Work Site
Figure
1.2 Location
of Dumping Area (from 29th
October 2001)
Figure
2.1 Location
of Air Quality Monitoring Stations
Figure
3.1 Location
of Noise Monitoring Stations
Figure
4.1 Location
of Water Quality Monitoring Stations
Appendices
Appendix B Amount of Dredged and Dumped Marine Sediment
Appendix C Action and Limit Levels for Air Quality, Noise, Water quality Monitoring
Appendix D Environmental
Monitoring Schedule
Appendix E Air
Quality Monitoring Results for November 2001
Appendix F Noise
Monitoring Results for November 2001
Appendix G Water
Quality Monitoring Results for November 2001
EXECUTIVE SUMMARY
This is the eighth 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 November 2001.
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 undertaken during the reporting month were dredging, placing of drainage layer and seawall
construction. Dredging work
was completed on 3/11/2001. 7,650m3
of marine mud was dredged from site and dumped at the allocated dumping area in
Cheung Chau during the month. No sand
filling activities were undertaken in the reporting month.
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 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 was
recorded in the month.
Water Quality
There were nine (9) cases of Action Level
exceedance and three (3) cases of Limit Level exceedance for water quality in
the reporting month. 9 out of 12 cases of action/limit level
exceedance were contributed by SS while 3 cases by Turbidity. 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, all of
these exceedances were considered not related to site activities and have been
explained to the satisfaction of EPD.
No further action was required.
It was
agreed by EPD that both NH3-N and TIN would be monitored throughout
the dredging phase and for at least one month upon completion of dredging. As the dredging work was completed on 3rd
November 2001, monitoring of NH3-N and TIN would be stopped from 4th
December 2001 onward.
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
(cancelled on 23/11/2001) |
GW-UW0256-01 |
29/06/01 |
07/12/01 |
Contractor |
29/06/01 |
|
Construction Noise Permit |
GW-UW0467-01 |
23/11/01 |
18/05/02 |
Contractor |
23/11/01 |
|
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 dredging activities as recommended in the EM&A manual were implemented in the
reporting month.
Environmental
Complaints
No
complaint against the construction
activities was received
in the reporting month.
Future Key
Issues
The future key issues to be
considered in the coming month are as follows:
-
To estimate the noise level
induced during the bored piling operation and to prepare the CNP application
for the bored piling works in advance.
-
to continue with the
preventive measures for noise mitigation and keep monitoring the performance;
-
to review the monitoring
results and to take action, if necessary, to ensure acceptable sea water
quality;
-
to provide routine
inspection and necessary maintenance for the silt curtains.
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 November 2001
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 undertaken
during the reporting month were dredging, placing of drainage layer and seawall
construction. A Layout Plan
showing the dredging locations for the Project is shown in Figure 1.1. Dredging work was completed on 3rd November 2001
and the total volume of dredged material from 1st to 3rd
November 2001 was 7,650m3. No sand filling activities were undertaken in the month. Uncontaminated materials were dumped at the
assigned location within the South Cheung Chau Spoil Disposal Area and the
total dumped volume in November 2001 was 7,650m3. Figure
1.2 shows dumping location for this project in November 2001. Daily records of dredged / dumped volume are presented
in Appendix B.
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 K.
Table 1.1 Construction Activities and Their Corresponding Environmental Mitigation Measures
|
Item |
Construction
Activities |
Environmental Mitigation Measures |
|
1 |
Dredging, Placing of Drainage Layer & Seawall Construction |
Water Quality- The number of grab dredgers operating in the site and the total dredging rate are limited; - Silt curtain are installed on the eastern, southern and north western sides of the site; - Fully-enclosed watertight grabs are used and the descent speed are controlled; - All barges for transport of dredged materials are fitted with tight bottom seals. Noise- General noise mitigation measures are employed at all work sites throughout the construction phase. Waste Management- Waste Management Plan is submitted and implemented. Dredging Waste- All vessels for marine transportation of dredged sediment are fitted with tight fitting seals to their bottom openings to prevent leakage; - Dredged waste are disposed of at Licensed site – South Cheung Chau; - Records of the quantities of waste generated and disposed off-site are taken. Marine Ecology- All construction related vessels approach the site from the designated route/channel to avoid disturbance to the finless porpoise. |
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.
Figure 1.2 Location of
Dumping Area (from 29th October 2001)
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 C
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 D.
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 H.
Dust monitoring was conducted as scheduled in the reporting month. All
monitoring data and graphical presentation of the monitoring results are
provided in Appendix E. 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.
As there
were no activities for the construction of the transmission system, no manual
noise measurement at the Pak Kok Tsui residences was carried out in the
reporting month. Appendix C 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.
Table
3.1 Noise Monitoring
Locations
|
Purpose of noise monitoring |
Monitoring Location |
|
Lamma Extension |
Ash Lagoon |
|
Lamma Extension |
Ching Lam |
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 |
|
Sound level meter |
Rion NA-27 |
|
Calibrator (IEC 60942 Class 1) |
Rion NC-74 |
3.4 Monitoring Parameters, Frequency and Duration
Continuous noise alarm monitoring of A-weighted Leq
levels was carried out at Ash Lagoon and Ching Lam. 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 |
3.5
Monitoring Procedures and
Calibration Details
Monitoring Procedures
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.
Equipment Calibration
The sound level meters and calibrators were verified by the manufacturer. Monthly calibration of the noise measuring equipment was carried out. Calibration details are shown in Appendix H.
Continuous noise monitoring was conducted at the two monitoring
stations at Ash Lagoon and Ching Lam.
All monitoring results and their graphical presentations are provided in Appendix F.
No
exceedance of noise Action/Limit Level was recorded in the month.
Marine
water quality monitoring at the monitoring locations adjacent to the dredging
and filling operations for Lamma Extension 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 dredging and
filling operations, 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 D.
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 · Total inorganic nitrogen, mg/L · Un-ionised ammonia, mg/L |
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 H.
Laboratory Analysis & QA/QC
The collected marine water samples were analyzed for Suspended Solids, Total Inorganic Nitrogen and Unionized Ammonia with methodologies as 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 |
|
Total Inorganic Nitrogen |
APHA 18 ed 4500 NO2 B & NO3 E + APHA 17ed 4500-NH3B, E |
0.01 |
|
Ammoniacal Nitrogen (Un-ionized Ammonia) |
APHA 17 ed 4500-NH3 G |
0.01 (Limit of Reporting for Ammoniacal Nitrogen) x degree of ionization |
Note: The determination of unionized ammonia was based on the articles entitled “Aqueous Ammonia Equilibrium Calculation: Effect of pH and Temperature” and “Ionization of Ammonia in Seawater: Effects of Temperature, pH and Salinity” which was accepted by EPD.
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, quality control samples and matrix spike recovery test).
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 H.
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 858 sets of samples (for Total Inorganic Nitrogen and
Unionized Ammonia) and 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 the following testing parameter are summarized in Appendix H.
· Suspended Solids
· Unionized Ammonia
· Total Inorganic Nitrogen
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 the following testing parameters and their duplicate results are summarized in Appendix H.
· Suspended Solids
· Unionized Ammonia
· Total Inorganic Nitrogen
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 are not applicable to all testing parameters due to the constraints of the testing parameters. The quality control samples results for the following testing parameters are shown in Appendix H.
· Unionized Ammonia
· Total Inorganic Nitrogen
Quality control sample testing is not applicable to the testing of Suspended Solids.
Matrix Spike:
Matrix spike is an intra-laboratory split of a digested sample spiked with target known concentration analyte to determine method bias in a given matrix. The matrix spike is applicable to the following tests:
· Unionized Ammonia
· Total Inorganic Nitrogen
Matrix spike testing is not applicable to testing of Suspended Solids. The matrix spike samples results are shown in Appendix H.
The QA/QC results in Appendix H 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, Total Inorganic Nitrogen and Unionized Ammonia 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 G. Key findings and observations are provided in the following
tables:
Summary of Exceedances in Turbidity (Depth
Average) in November 2001
|
Monitoring Dates |
No. of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
2nd November |
0 |
0 |
N. A. |
|
5th November |
0 |
0 |
N. A. |
|
7th November |
0 |
0 |
N. A. |
|
9th November |
0 |
0 |
N. A. |
|
12th November |
0 |
0 |
N. A. |
|
14th November |
1 (SR7
during ebb tide) |
0 |
Not related to
site activities. Based on the observation made by the sampling team, no
noticeable sediment plume migration from the direction of the site to the
sampling location was observed. Moreover, there was no dredging or sand
filling activity on-site during the said exceedance. Besides, the measurement
result at SR5 and SR6 (which is located between the site and SR7) were lower
than the said exceedance therefore the elevated result at SR7 was considered
not relevant to the site activities. Furthermore, the measurement result at
the same location during the following session (PM) of the same sampling day
was below the action level. |
|
16th November |
0 |
0 |
N. A. |
|
20th November |
0 |
0 |
N. A. |
|
22nd November |
0 |
0 |
N. A. |
|
24th November |
0 |
0 |
N. A. |
|
26th November |
0 |
0 |
N. A. |
|
28th November |
0 |
0 |
N. A. |
|
30th November |
2 (SR1
and SR6 during flood tide) |
0 |
Not related to
site activities. Based on the observation made by the sampling team, no
noticeable sediment plume migration from the direction of the site to the
sampling locations were observed. Moreover, there was no dredging or sand
filling activity on-site during the said exceedances. On the other hand, it was found that the measurement result at SR2
(which is located between SR1 and the site) was lower than the action level
therefore it was considered that elevated measurement at SR1 during flood
tide was not related to the site activities. Besides, SR6 was located at the
upstream to the site during the course of sampling while the marine water
flowing from South to North. Hence, the elevated measurement results might be
due to the occasional background fluctuation rather than the site activities. |
Summary of Exceedances in Suspended Solids
(Depth Average) in November 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
2nd November |
1 (SR6 during ebb tide) |
0 |
Not related to site activities. Based on the
observation made by the sampling team, no sediment plume migration from the
direction of site to the sampling location was observed. Moreover, the
dredging volume was greatly reduced on that day and there was no sand filling
activity on-site during the said exceedance. Furthermore, the measurement
result at the same location during the PM session of the same sampling day
was below the action level. Hence, the elevated result might be due to the occasional
background fluctuation rather than the site activities. |
|
5th November |
1 (SR6 during flood tide) |
1 (SR4 during flood tide) |
Not related to site activities. Based on the
observation made by the sampling team, no sediment plume migration from the
direction of site to the sampling location was observed. Moreover, there was
no dredging or sand filling activity on-site during the said exceedances. For
the exceedance at SR4 during flood tide, the measurement result during the PM
session of the same sampling day was below the action level. In view of this,
the said exceedance might be due to background fluctuation. Besides, SR6 was located
at the upstream to the site during the course of sampling while the marine
water flowing from South to North. Therefore, the elevated SS result at SR6 might
be due to the occasional background fluctuation rather than the site
activities. |
|
7th November |
0 |
1 (SR5 during flood tide) |
Not related to site activities. Based on the
observation made by the sampling team, no sediment plume migration from the
direction of site to the sampling location was observed. Moreover, there was
no dredging or sand filling activity on-site during the said exceedance. Besides,
SR5 was located at the upstream to the site during the course of sampling while
the marine water flowing from South to North. Therefore, the elevated SS
result might be due to the occasional background fluctuation rather than the
site activities. |
|
9th November |
0 |
0 |
N. A. |
|
12th November |
0 |
1 (SR6
during flood tide) |
Not related to site activities. Based on the
observation made by the sampling team, no sediment plume migration from the
direction of site to the sampling location was observed. Moreover, there was
no dredging or sand filling activity on-site during the said exceedance. Besides,
SR6 was located at the upstream to the site during the course of sampling while
the marine water flowing from South to North. Therefore, the elevated SS
result might be due to the occasional background fluctuation rather than the
site activities. |
|
14th November |
2 (SR1
during flood tide & SR7 during ebb tide) |
0 |
Not related to
site activities. Based on the observation made by the sampling team, no
noticeable sediment plume migration from the direction of the site to the
sampling location was observed. Moreover, there was no dredging or sand
filling activity on-site during the said exceedances. Besides, the
measurement result at SR7 during the PM session of the same sampling day was
below the action level. In view of this, the said exceedance might be due to
background fluctuation. For the exceedance at SR1 during flood tide, since
measurement result at SR2 (which is located between the site and SR1) was
lower than the action level, therefore the elevated result at SR1 was also
considered not relevant to the site activities |
|
16th November |
0 |
0 |
N. A. |
|
20th November |
0 |
0 |
N. A. |
|
22nd November |
0 |
0 |
N. A. |
|
24th November |
0 |
0 |
N. A. |
|
26th November |
0 |
0 |
N. A. |
|
28th November |
1 (SR7
during ebb tide) |
0 |
Not related to
site activities. Based on the observation made by the sampling team, no
noticeable sediment plume migration from the direction of the site to the
sampling location was observed. Moreover, there was no dredging or sand
filling activity on-site during the said exceedance. Besides, the measurement
result at SR7 during the PM session of the same sampling day was below the
action level. Therefore, the said exceedance might be due to background
fluctuation. |
|
30th November |
1 (SR6
during flood tide) |
0 |
Not related to site activities. Based on the
observation made by the sampling team, no sediment plume migration from the
direction of site to the sampling location was observed. Moreover, there was
no dredging or sand filling activity on-site during the said exceedance. Besides,
SR6 was located at the upstream to the site during the course of sampling.
Therefore, the elevated result might be due to the occasional background
fluctuation rather than the site activities. |
There were nine cases (9) of Action Level
exceedance and three (3) cases of Limit Level exceedance for water quality in
the reporting month. 9 out of 12 cases of action/limit level
exceedance were contributed by SS while 3 cases by Turbidity. 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, all of these 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.
There
was no AL exceedance recorded for Dissolved Oxygen (Bottom) and and Dissolved
Oxygen (Surface & Middle) for the monitoring month. Further, all measurement results of TIN
and NH3 were below the maximum level of TIN and NH3 collected
at EPD's monitoring stations in
the vicinity during the past five years.
It was
agreed by EPD that both NH3-N and TIN would be monitored throughout
the dredging phase and for at least one month upon completion of dredging. As the dredging work was completed on 3rd
November 2001, monitoring of NH3-N and TIN would be stopped from 4th
December 2001 onward.
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 November 2001 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) |
01/11/01-30/11/01 |
0 |
0 |
|
|
|
2 |
Ambient TSP (1-hour) |
01/11/01-30/11/01 |
0 |
0 |
|
|
|
Noise |
||||||
|
1 |
Noise level at the critical NSR’s predicted by the noise alarm monitoring system |
01/11/01-30/11/01 |
0 |
0 |
|
|
|
2 |
Manual noise monitoring at the Pak Kok Tsui residences |
01/11/01-30/11/01 |
NA |
NA |
Construction of transmission system not yet commenced. |
|
|
Water |
||||||
|
1 |
DO (Surface & Middle) |
01/11/01-30/11/01 |
0 |
0 |
|
|
|
2 |
DO (Bottom) |
01/11/01-30/00/01 |
0 |
0 |
|
|
|
3 |
SS |
01/11/01-30/11/01 |
6 |
3 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
|
4 |
Turbidity |
01/11/01-30/11/01 |
3 |
0 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
Waste
Management Records
The estimated amounts of different types of waste
generated in November 2001 are shown in Table 5.2.
Table
5.2 Estimated Amounts of Waste
Generated in November 2001
|
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 |
1 |
The total bulk volume of dredged material was 7,650m3.
No sand filling took place.
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 J.
5.4 Status of Environmental Licensing and Permitting
Construction Noise Permit
(CNP) (GW-UW0256-01) was cancelled and another CNP (GW-UW-0467-01) was issued
on 23rd November 2001. 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-UW0256-01 |
29/06/01 |
07/12/01 |
4 derrick barges, 5 dredger grabs and 6 tug boats before 2300 5 grab dredgers and 2 tug boats from 2300 to 0700 next day with a condition
restricting the location of the grab dredger (CNP063) |
Cancelled
on 23/11/2001 |
|
Construction Noise Permit |
GW-UW0467-01 |
23/11/01 |
18/05/02 |
4 groups of PME’s, viz. (A) 6 derrick barges
& 2 tug boats, (B) 3 derrick barges, 1 grab dredger & 1 tug boat, (C)
2 derrick barges & 3 tug boats, (D) 8 derrick barges, 1 grab dredger, 4
tug boats, 4 sand placing barges & 4 rotary type drill rigs (diesel). Only one group can be used. Group D shall not be operated from
11:00pm to 7:00am on next day. |
Valid. Issued on 23/11/2001 |
|
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 K.
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 I.
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
No environmental complaint against the construction activities was received in November 2001.
Table 5.4 Environmental
Complaints / Enquiries Received in November 2001
|
Case
Reference / Date, Time
Received / Date, Time
Concerned |
Descriptions
/Actions Taken |
Conclusion
/ Status |
|
Nil |
N/A |
N/A |
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:
Construction Noise Impact
· To estimate the noise level induced during the bored piling operation and to prepare the CNP application for the bored piling works in advance.
· To continue the preventive measures for noise exceedance and keep monitoring/ reviewing the performance.
Construction 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.
6.3 Monitoring Schedules for the Next 3 Months
The tentative environmental monitoring schedules for the next 3 months are shown in Appendix D.
6.4 Construction Program for the Next 3 Months
The tentative construction program for the next 3 months is shown in Appendix L.
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.
A total of 12 cases of action/limit level exceedance on water quality parameters were recorded in the reporting month. As all 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 dredging
activities were implemented in the reporting month. No environmental complaint against the construction activities was
received in the reporting
month. No prosecution was
received for this Project
in the reporting period.
The environmental performance of the Project was generally
satisfactory.
