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 May 2001
Table 5.3 Summary of
Environmental Licensing and Permit Status
Table 5.4 Environmental Complaints / Enquiries Received in May 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 12th
April 2001)
Figure 1.3 Location
of Dumping Area (from 14th May 2001)
Figure
1.4 Location
of Dumping Area (from 24th May 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 A Organization
Chart
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 May 2001
Appendix F Noise Monitoring Results for May 2001
Appendix G Water Quality Monitoring Results for May 2001
Appendix H The QA/QC Procedures and Results
Appendix I Event/Action Plans
Appendix J Site Audit Summary
Appendix K Summary of EMIS
Appendix L Tentative Construction Programme
Appendix M Photograph
for the Observation During Water Sampling
This is the second 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 May 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.
Environmental
Monitoring Works
All monitoring work at designated stations was performed
on schedule in the reporting period.
Air Quality
No exceedance
of Action and Limit levels for air
quality was recorded in the
month.
Noise
With the availability of the Construction Noise
Permits, construction
work was carried out during the restricted hours including evening time and
holidays and night-time. No exceedance of Action and Limit levels for noise was recorded in the month.
Water Quality
A total of one hundred
cases of Action level exceedance and fifty cases of Limit
Level exceedance for water quality were recorded in the reporting month. 99 out of 150 cases of
action/limit level exceedances were contributed by TIN and NH3-N
while 48 cases by DO. For these
exceedances, comprehensive investigations have been carried out. It is found that similar measurement
results were also obtained at the control stations during the monitoring period,
suggesting that the background DO levels were already low and TIN & NH3-N
levels were already high.
Furthermore, when compared with EPD’s published monitoring data at the
monitoring locations adjacent to Lamma Island, all the measurement results exceeding
Action/Limit Levels lay within the range of EPD’s data. This indicated that the measured data
only reflected the background fluctuation.
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, HEC would review with EPD the impact monitoring programme
for water quality and would come up with a better criteria for establishing
action and limit levels accordingly.
Site Environmental Audit
Some malpractices of the
contractor contravening the marine dumping permit were spotted by EPD on 7th
May 2001. The contractor has been
warned by HEC to take necessary actions to prevent them from happening
again. 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/A |
22/12/00 |
- |
HEC |
22/12/00 |
Construction Noise Permit |
GW-UW0109-01 GW-UW0163-01 (superceded by GW-UW0180-01) GW-UW0180-01 |
02/04/01 24/04/01 08/05/01 |
01/10/01 08/10/01 18/10/01 |
Contractor Contractor Contractor |
31/03/01 24/04/01 08/05/01 |
Dumping Permit |
EP/MD/01-174 |
07/04/01 |
06/10/01 |
Contractor |
27/03/01 |
Implementation
Status of Environmental Mitigation Measures
Environmental
mitigation measures for the dredging activities were implemented in the
reporting month.
Environmental
Complaints
No
complaint was received in the reporting month.
Concluding Remarks
Except the malpractices of
the contractor spotted by EPD on 7th May 2001, 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/A, 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
following outlines the key elements of the Project including the construction
activities associated with the transmission system and submarine gas pipeline.
· 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 May 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 and dumping of dredged mud. A Layout Plan showing the dredging locations for the Project is shown in Figure 1.1. The total volume of dredged material from 1st to 31st May 2001 was 908,837m3. No 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 May 2001 was 908,837m3. The contractor was informed by EPD (via a letter ref: ( ) in EP 60/G1/12-51 XI dated 3rd May 2001) of the relocation of the Spoil Disposal Area with effect from 14th May 2001. Another relocation of the Spoil Disposal Area effective from 24th May 2001 was notified to the contractor by EPD (viz a letter ref: (76) in EP 60/G1/12-51 XI dated 23rd May 2001). Figure 1.2, Figure 1.3 and Figure 1.4 show all dumping locations for this project in May 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 |
The following mitigation measures related to dredging have been
implemented:
|
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
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 any deterioration of water quality could be detected and that
timely action would 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. Appendix C shows the
established Action/Limit Levels for water quality.
A total of twelve 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 baseline 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 |
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 sample digested 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 Dissolved Oxygen
(Surface and Middle) in May 2001
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
0 |
N. A. |
4th May |
0 |
0 |
N. A. |
7th May |
0 |
0 |
N. A. |
9th May |
0 |
0 |
N. A. |
11th May |
0 |
0 |
N. A. |
15th May |
0 |
0 |
N. A. |
17th May |
0 |
0 |
N. A. |
19th May |
1 (SR1 at mid-flood) |
0 |
Not related to site
activities because by reviewing the literature data from EPD in 1999, the
said measurement result lay within the ranges of
measurement data collected by EPD, suggesting that the low DO
measurement results at the said impact location might reflect the background
fluctuation. |
21st May |
0 |
0 |
N. A. |
23rd May |
7 (SR1 at mid-ebb and SR1,
SR2, SR4, SR5, SR6 and SR7 during mid-flood) |
0 |
Not related to site
activities since the measurement results at control stations were also low,
suggesting that the background DO concentration was low. |
25th May |
0 |
0 |
N. A. |
28th May |
4 (SR1 & SR2 during
mid-ebb and mid-flood) |
0 |
Not related to site activities since by reviewing the EPD's literature data of 1999 (WM1), the said measurement all lay in the measurement range, suggesting that the low DO measurement results at the said impact locations might reflect the background fluctuation |
30th May |
4 (SR1 & SR2 during
mid-ebb and mid-flood) |
0 |
Not related to site
activities since by reviewing the literature data from EPD in 1999 (WM1), the
measurement results lay within the measurement
range, suggesting that the said exceedances might be due to the background fluctuation. |
Summary of Exceedances in Dissolved Oxygen
(Bottom) in May 2001
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
0 |
N. A. |
4th May |
0 |
0 |
N. A. |
7th May |
0 |
0 |
N. A. |
9th May |
0 |
0 |
N. A. |
11th May |
0 |
0 |
N. A. |
15th May |
0 |
0 |
N. A. |
17th May |
0 |
0 |
N. A. |
19th May |
2 (SR1& SR7 during mid-flood) |
0 |
Not related to
the site activities as the results of the control stations
were also low, suggesting that the marginal low measurement results might be due to the
background fluctuation. |
21st May |
4 (SR1, SR2 & SR7 during mid-ebb and SR6 during mid-flood) |
0 |
Not related to the site
activities as by reviewing the literature data from EPD in 1999 (WM1 &
SM5), the said measurement results were all within the ranges of measurement
data collected by EPD, suggesting that the marginal low measurement results were
due to the background fluctuation. |
23rd May |
12 (All stations except SR3 at mid-flood and mid-ebb) |
0 |
Not related to the site activities as by reviewing
the literature data of EPD in 1999 (WM1 & SM5), the said exceedances lay
within the range of measurement, suggesting that low
measurement results were due to the background fluctuation. |
25th May |
2 (SR1 and SR2 during mid-flood) |
0 |
Not related to the site
activities as by reviewing the literature data from EPD at the vicinity of
the monitoring location (WM1) in 1999, the measurement results lay within the measurement range at WM1, suggesting
that the low DO measurement might reflect the background fluctuation of the
sampling location. |
28th May |
7 (SR1 & SR2 during mid-ebb and SR1, SR2, SR5, SR6 and SR7 during
mid-flood) |
0 |
Not related to the site activities as by reviewing the EPD's literature data of 1999 (SM5), the said measurement lay in the measurement range, suggesting that the low DO measurement results at the said impact locations might reflect the background fluctuation. |
30th May |
5 (SR2 &SR7 during
mid-ebb and SR1, SR2 & SR7 during mid-flood) |
0 |
Not related to the site
activities as by reviewing the literature data from EPD in 1999 (WM1), the
measurement results lay within the measurement
range, suggesting that the
said exceedances might be due to background
fluctuation. |
Summary of Exceedances in Turbidity (Depth
Average) in May 2001
Monitoring Dates |
No. of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
0 |
N. A. |
4th May |
0 |
0 |
N. A. |
7th May |
0 |
0 |
N. A. |
9th May |
0 |
0 |
N. A. |
11th May |
0 |
0 |
N. A. |
15th May |
0 |
0 |
N. A. |
17th May |
0 |
0 |
N. A. |
19th May |
0 |
0 |
N. A. |
21st May |
0 |
0 |
N. A. |
23rd May |
0 |
0 |
N. A. |
25th May |
0 |
0 |
N. A. |
28th May |
0 |
0 |
N. A. |
30th May |
0 |
0 |
N. A. |
Summary of Exceedances in Suspended Solids
(Depth Average) in May 2001
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
0 |
N. A. |
4th May |
0 |
0 |
N. A. |
7th May |
0 |
1 (SR2 during flood tide) |
Not related to the site
activities. Based on the on-site
observation made by the sampling team,
no obvious dust plume migrated from the site area to the said monitoring
station was observed during the course of sampling; and no particular
activities were carried out at the vicinity of the sampling location. Further, the measurement result on the subsequent
sampling was below the Action Level.
Therefore, the said exceedance might be due
to background fluctuation. |
9th May |
1 (SR1 during flood tide) |
0 |
Not related to the site
activities. This was because the
measurement result at SR2 (which is located between SR1 and the construction site) was much less than the result at SR1.
|
11th May |
0 |
0 |
N. A. |
15th May |
0 |
0 |
N. A. |
17th May |
0 |
0 |
N. A. |
19th May |
0 |
0 |
N. A. |
21st May |
0 |
0 |
N. A. |
23rd May |
0 |
0 |
N. A. |
25th May |
0 |
0 |
N. A. |
28th May |
0 |
1 (SR1 during flood tide) |
Not
related to the site activities.
Based on the on-site observation made by the environmental consultant, a fishing
boat was just traveling in the vicinity of the sampling location,
which resulted in the re-suspension of sediment from the bottom. A photograph showing the fishing boat is
given in Appendix M. |
30th May |
0 |
0 |
N. A. |
Summary of Exceedances in Unionized Ammonia
(Depth Average) in May 2001
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if
any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
0 |
N. A. |
4th May |
6 (SR5, SR6 & SR7
during mid-flood and mid-ebb) |
0 |
Not related to site
activities since the measurement results at the upstream control stations
were even higher than the impact monitoring results, suggesting that the background concentrations
were already high. |
7th May |
6 (SR2 & SR7 during
mid-ebb and SR2, SR5, SR6 & SR7 during mid-flood) |
0 |
Not related to site
activities since the measurement results at
the upstream control stations were also high. |
9th May |
2 (SR2 during ebb tide and
SR5 during flood tide) |
0 |
Not related to site activities since the measurement results of the upstream control stations were much higher than the impact station's results. |
11th May |
7 (SR2, SR5, SR6 & SR7
during ebb tide and SR5, SR6 & SR7 during flood tide) |
0 |
Not related to site
activities since the measurement result of SR2 during ebb tide was the same
as SR1, suggesting that the
elevated measurement result might be due
to the traveling of marine water from NE part of Lamma Island. The marginal exceedance at
SR5, SR6 and & SR7 were not related to site activities since the
measurement result at the upstream control stations were much higher. |
15th May |
0 |
0 |
N. A. |
17th May |
1 (SR6 during flood tide) |
0 |
By
reviewing the observation recorded during the course of sampling, no noticeable
plume of sediment-loaded marine water dispersed from the project area to the
monitoring station was observed.
Further, the SS
results and TIN results at the same location were well below the Action Level. Therefore it was considered that the
elevated NH3 result might not be associated with the site activities. |
19th May |
6 (SR5, SR6 & SR7
during ebb tide and flood respectively) |
0 |
Not related to site activities since the measurement results at the upstream control stations were much higher. |
21st May |
4 (SR5, SR6 & SR7
during ebb tide and SR6 during flood tide) |
0 |
Not related to site activities since the measurement results of the upstream control station were much higher, suggesting that the background concentrations at the study area were also high. |
23rd May |
5 (SR1, SR5 & SR6
during ebb tide and SR5 & SR 6 during flood tide) |
0 |
Based on the on-site observation made by the sampling team, no noticeable activities
were observed from the direction of construction site, which resulted in the elevated NH3 measurement
results at SR1. Further, the NH3 result recorded in the subsequent measurement on 25th May was below the
Action Level. Therefore, the marginal
exceedance at SR1 during ebb tide might not be related to site activities. The marginal exceedances
at SR5 and SR6 during ebb tide were also not related to site activities since
the measurement result at the upstream control stations were also high. The marginal exceedance at SR5 during flood tide was not related to site activities because the measurement result at the upstream control C4 was also high. For the exceedance at SR6
during flood tide, SR6 located upstream to the site area during the course of
sampling and therefore the elevated measurement result might not be
associated with the marine water flowing
from the site area. |
25th May |
0 |
0 |
N. A. |
28th May |
0 |
0 |
N. A. |
30th May |
2 (SR5 & SR6 during
ebb tide) |
0 |
Not related to site
activities since the measurement results at upstream control stations were
much higher. Therefore, the elevated measurement results might be due to the background fluctuation instead of the
site activities. |
Summary of Exceedances in Total Inorganic
Nitrogen (Depth Average) in May 2001
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
Action Level |
Limit Level |
||
2nd May |
0 |
2 (SR2 during ebb tide and SR6 during flood tide) |
Not related to site activities since the upstream control station measurement result at C3 was higher than the measurement result at SR2 during ebb tide. The measurement result at SR6 during flood tide
was not related to site activities because the measurement
result lay within the range of
EPD literature data in 1999 (SM5), suggesting that the elevated TIN results at the said impact locations
might reflect the background fluctuation. |
4th May |
0 |
0 |
N. A. |
7th May |
2 (SR1
during ebb tide and flood tide) |
7 (SR2, SR4 & SR7 during ebb tide and SR2, SR5,
SR6 & SR7 during flood tide) |
Not related to site activities since the
measurement results at upstream control stations were also high. |
9th May |
2 (SR1 during ebb tide and
SR4 during flood tide) |
3 (SR2, SR4 & SR6
during ebb tide) |
Not related to site activities since
the measurement results of the corresponding upstream control stations were also high. |
11th May |
1 (SR1 during ebb tide) |
2 (SR2 during ebb tide and
SR3 during flood tide) |
Not related to site
activities since the measurement result at the upstream control stations were
also high. Further, the measurement result lay
within the range of EPD literature data in 1996 (SM5),
suggesting that the elevated TIN results at the said impact locations might
reflect the background fluctuation. |
15th May |
0 |
0 |
N. A. |
17th May |
0 |
0 |
N. A. |
19th May |
0 |
4 (SR2 during ebb tide and
SR4, SR5 & SR6 during flood tide) |
Not related to site
activities since the measurement results at the upstream control stations
were much higher. |
21st May |
2 (SR1 during ebb tide and
flood tide) |
10 (SR2, SR4, SR5, SR6
& SR7 during ebb tide and flood tide) |
Not related to site activities since
the measurement results of the upstream control stations were also high, suggesting the background concentrations at the
study area were already high |
23rd May |
1 (SR1 during ebb tide) |
10 (SR2, SR4, SR5, SR6
& SR7 during ebb tide and flood tide) |
Not related to the site
activities. The Limit Level exceedances
at SR4, SR5 and SR7 were not related to site activities since the measurement
result at Control Station C4 was also high. For the Action Level
exceedance at SR1 and Limit Level exceedances at SR2 and SR6, the measurement
results lay
within the range of EPD literature data in 1999 (WM1 & SM5),
suggesting that the elevated TIN results at the said impact locations might
reflect the background fluctuation. |
25th May |
1 (SR1 during ebb tide) |
0 |
Not related to the site
activities since the measurement result of the upstream control station C1
was also high. |
28th May |
2 (SR1 during ebb tide and
flood tide) |
8 (SR2, SR4 & SR5
during ebb tide and SR2, SR4, SR5, SR6 & SR7 during flood tide) |
Not related to site activities since
the measurement results of the corresponding upstream control stations were
much higher than the impact station's results. |
30th May |
1 (SR1 during ebb tide) |
2 (SR2 during ebb tide and
flood tide) |
Not related to the site activities as the measurement results of the upstream control stations were even higher than that measured at the impact monitoring stations. |
A total of one hundred cases of Action level exceedance and fifty cases
of Limit Level exceedance for water quality were recorded in the reporting
month. 99 out of 150 cases of
action/limit level exceedances were contributed by TIN and NH3-N
while 48 cases by DO. For these exceedances,
comprehensive investigations have been carried out. It is found that similar measurement results were also
obtained at the control stations during the monitoring period, suggesting that
the background DO levels were already low and TIN & NH3-N levels
were already high. Furthermore,
when compared with EPD’s published monitoring data at the monitoring locations
adjacent to Lamma Island, all the measurement results exceeding Action/Limit
Levels lay within the range of EPD’s data. This indicated that the measured data only reflected the
background fluctuation.
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. IEC and the
construction contractor have been informed of the exceedances accordingly as
per the requirements of the EM&A Manual. Nevertheless, HEC would review
with EPD the impact monitoring programme for water quality and would come up
with a better criteria for establishing action and limit levels accordingly.
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 May 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) |
01/05/01-31/05/01 |
0 |
0 |
|
|
2 |
Ambient TSP (1-hour) |
01/05/01-31/05/01 |
0 |
0 |
|
|
Noise |
||||||
1 |
Noise level at the critical NSR’s predicted by the noise alarm monitoring system |
01/05/01-31/05/01 |
0 |
0 |
|
|
2 |
Manual noise monitoring at the Pak Kok Tsui residences |
01/05/01-31/05/01 |
NA |
NA |
Construction of transmission system not yet commenced. |
|
Water |
||||||
1 |
DO (Surface & Middle) |
01/05/01-31/05/01 |
16 |
0 |
The exceedances were considered not related to the construction site. Please refer to section 4 of the report for details. |
|
2 |
DO (Bottom) |
01/05/01-31/05/01 |
32 |
0 |
The exceedances were considered not related to the construction site. Please refer to section 4 of the report for details. |
|
3 |
SS |
01/05/01-31/05/01 |
1 |
2 |
The exceedances were considered not related to the construction site. Please refer to section 4 of the report for details. |
|
4 |
Turbidity |
01/05/01-31/05/01 |
0 |
0 |
|
|
5 |
NH3-N |
01/05/01-31/05/01 |
39 |
0 |
The exceedances were considered not related to the construction site. Please refer to section 4 of the report for details. |
|
6 |
TIN |
01/05/01-31/05/01 |
12 |
48 |
The exceedances were considered not related to the construction site. Please refer to section 4 of the report for details. |
|
Waste
Management Records
The estimated amounts of different types of waste
generated in May 2001 are shown in Table 5.2.
Table
5.2 Estimated Amounts of Waste
Generated in May 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 908,837m3. No filling took place.
EPD officials have inspected the construction site on 7th May
2001. The following malpractices
at one fully loaded dumping barge of the contractor, HB503S (Vessel No. 22111V)
were found to have contravened the marine dumping conditions:
-
Powering off the Automatic Self Monitoring Device;
-
Failure to produce a copy of the marine dumping permit.
The contractor has been warned on the spot about the malpractices. HEC issued a warning letter to the
contractor to remind them to take some necessary actions to avoid them from
happening again.
Site audits were
carried out by ET on a weekly basis to monitor environmental issues on 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
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/A |
22/12/00 |
- |
The whole construction work sites |
Valid |
Construction Noise Permit |
GW-UW0109-01 GW-UW0163-01 GW-UW0180-01 |
02/04/01 24/04/01 08/05/01 |
01/10/01 08/10/01 18/10/01 |
4 derrick barges, 4 dredger grabs and 6 tug boats for 0700 to 2300
& holiday 2 dredger barges and 1 tug boat for 2300 to 0700 next day 4 grab dredgers and 2 tug boats for 2300 to 0700 next day with conditions restricting the location of the grab dredgers and tug boats to various zones of the construction site |
Valid Superseded
by GW-UW0180-01 on 18/05/01 Valid |
Dumping Permit |
EP/MD/01-174 |
07/04/01 |
06/10/01 |
Dumping at South Cheung Chau Disposal Area (Relocation of the Spoil Disposal Area with effective from 14th May 2001 and 24th May 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) 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 requirements of the EM&A Manual. Investigation findings of the limit level exceedances in TIN recorded on 7th May 2001, 9th May 2001 and 11th May 2001 were submitted to EPD by letter on 29th May 2001 in response to the two letters from EPD ref: (4) in Ax(5) to EP2/N9/D/60 Pt.2 and (5) in Ax(5) to EP2/N9/D/60 Pt.2 dated 18th May 2001 and 22nd May 2001 respectively.
5.7 Implementation Status of Environmental Complaint Handling Procedures
There was no complaint / enquiry on environmental issues received in May 2001.
Table 5.4 Environmental
Complaints / Enquiries Received in May 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
continue the preventive measures for noise exceedance and keep monitoring/reviewing the performance
Construction
Water Impact
· To keep reviewing the monitoring results and to take corresponding action to ensure the sea water quality, if necessary
· 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 150 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 can be devised.
Environmental
mitigation measures recommended in the EM&A manual for the dredging
activities were implemented in the reporting month. No environmental complaint was received in the reporting month. No prosecution was received for
this Project in the
reporting period.
Except the
malpractices of the contractor spotted by EPD on 7th May 2001, the
environmental performance of the
Project was generally satisfactory.