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 June 2001
Table 5.3 Summary of
Environmental Licensing and Permit Status
Table 5.4 Environmental Complaints / Enquiries Received in June 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 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 June 2001
Appendix F Noise Monitoring Results for June 2001
Appendix G Water Quality Monitoring Results for June 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 third 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 June 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 and dumping of dredged mud.
1,018,674m3 of marine
mud was dredged from site and dumped at the allocated dumping area in Cheung
Chau during the month. No filling
activities were undertaken in the reporting month.
Environmental
Monitoring Works
Two marine water quality
monitoring works on 8th June 2001 and 27th June 2001 were
rescheduled due to adverse weather conditions. The makeup sampling for 8th June 2001 was scheduled
on 14th June 2001 while that for 27th June 2001 was arranged
on 28th June 2001.
Other than these, 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, holidays
and night-time.
No exceedance
of Action and Limit levels for noise was
recorded in the month.
Water Quality
There were 309 cases of Action level exceedance and 142 cases of Limit Level exceedance in
the reporting month. 238 out of 451 cases of action/limit
level exceedances were contributed by TIN and NH3-N while 205 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 also low and TIN & NH3-N levels
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
showed that the Action/Limit level as established by the baseline monitoring
work which was carried out during cooler season, was not appropriate for the
current water body condition.
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 revise the criteria for establishing action and
limit levels accordingly.
Site Environmental Audit
EPD
officials have inspected the construction site on 20th June 2001.
They were generally satisfied with the
environmental performance of the Project. 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-UW0180-01 (supserseded by GW-UW0256-01) GW-UW0256-01 |
02/04/01 08/05/01 29/06/01 |
01/10/01 18/10/01 07/12/01 |
Contractor Contractor Contractor |
31/03/01 08/05/01 29/0601 |
|
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 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 prepare the CNP
application for bored piling works;
-
to continue with the preventive
measures for noise exceedance and keep monitoring the performance;
-
to review the monitoring
results and to take actions, if necessary, to ensure the 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/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
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 June 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 30th June 2001 was 1,018,674m3. 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 June 2001 was 1,018,674m3. Figure 1.2 shows dumping location for this project in June 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.
Figure 1.2 Location of Dumping Area (from 24th May 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. Appendix C shows the established
Action/Limit Levels for water quality.
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 (C) stations 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.
Two marine
water quality monitoring works on 8th June 2001 and 27th
June 2001 were rescheduled due to adverse weather conditions. The makeup sampling for 8th
June 2001 was scheduled on 14th June 2001 while that for 27th
June 2001 was arranged on 28th June 2001. Other than these, 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 June 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
6 (SR1 & SR2 during ebb tide and flood tide and SR5 & SR6
during flood tide) |
0 |
Not related to site activities as by reviewing the
literature data from EPD in 1999(WM1 & SM5), the said exceedances lay
within the range of measurement results, suggesting that the low DO
measurement might be due to background fluctuation. |
|
4th June |
0 |
0 |
N.
A. |
|
6th June |
6 (SR1, SR2 & SR7
during ebb tide and flood tide) |
0 |
Not
related to site activities as by reviewing the literature data from EPD in
1999 (WM1
& SM5), the said exceedances lay within the range
of EPD’s measurement data, suggesting that the exceedances might be due to
background fluctuation. |
|
11th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not
related to site activities as the exceedances at SR1 and SR2 lay within the
range of measurement data collected by EPD in 1999 (WM1), which indicated
that the exceedances might be due to background fluctuation. For the exceedances at SR4, SR5, SR6 and SR7, the measurement
results at upstream control were even lower than the corresponding Action
Levels, suggesting that the background DO level was already low. |
|
13th June |
5 (SR1 & SR7 during ebb tide and flood tide and SR2 during flood
tide) |
0 |
Not
related to site activities as the measurement results at upstream control
stations were lower than the corresponding Action Levels, suggesting that the
background DO was already low. Besides, all exceedances lay within the range
of measurement result collected by EPD in 1999 (WM1 & SM5). |
|
14th June |
7 (SR1 & SR2 during ebb tide and flood and SR4, SR5 & SR6
during flood tide) |
0 |
Not
related to site activities as the measurement results at upstream control
stations were lower than the corresponding Action Levels, suggesting that the
background DO was already low. Besides, all exceedances lay within the range
of measurement result collected by EPD in 1999 (WM1 & SM5). |
|
15th June |
7 (SR1, SR2 & SR7 during ebb tide and flood tide and SR6 during
ebb tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were as low as the said exceedances,
suggesting that the background DO was already low. |
|
18th June |
2 (SR1 & SR7 during
flood tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were as low as the said exceedances,
suggesting that the background DO was already low. |
|
20th June |
2 (SR1 & SR2 during
flood tide) |
0 |
Not related to site activities as by reviewing the
EPD’s literature data of 1999 (WM1), the said exceedances lay within the
measurement range, suggesting the low DO measurement results at said impact
locations might reflect the background fluctuation. |
|
22nd June |
4 (SR1 & SR2 during
ebb tide and flood tide) |
0 |
Not related to site activities as all measurement
results lay within the range of measurement results collected by EPD in 1999
(WM1), suggesting that the exceedances might be due to background
fluctuation. |
|
25th June |
7 (SR1, SR6 & SR7 during
ebb tide and flood tide and SR2 during flood) |
0 |
Not related to site activities as the said
exceedances were as low as the measurement results at upstream control
stations, which indicated that the background DO level was already low. |
|
28th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities since all exceedances during ebb tide were as low as the measurement results at upstream control stations, suggesting that the background DO was already low. For the exceedances during flood tide, all measurement results lay within the measurement range collected by EPD in 1999 (WM1 & SM5), which indicated that low DO might be due to background fluctuation. |
|
29th June |
6 (SR1, SR2 & SR7
during ebb tide and flood tide) |
0 |
Not related to site activities since the said
exceedances lay within the measurement range collected by EPD in 1999 (WM1
& SM5), which indicated that low DO might be due to background
fluctuation. |
Summary of Exceedances in Dissolved Oxygen
(Bottom) in June 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
8 (SR1, SR2 & SR5 during ebb tide and flood tide and SR4 & SR6
during ebb tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were lower than the said exceedances during
ebb tide, suggesting that the background was already low. For the exceedances
during flood tide, all measurement results lay within the measurement range
collected by EPD in 1999 (WM1 & SM5), suggesting the low DO might be due to
background fluctuation. |
|
4th June |
0 |
0 |
N. A. |
|
6th June |
9 (SR1, SR2, SR6 & SR7
during ebb tide and flood tide and SR4 during flood) |
0 |
Not
related to site activities as by reviewing the literature data from EPD in
1999 (WM1
& SM5), the said exceedances lay within the ranges
of measurement data, suggesting that the exceedances might be related to
background fluctuation. |
|
11th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not
related to site activities as by reviewing the literature data from EPD in
1999 (WM1
& SM5), the exceedances at SR1 and SR2 lay within
the ranges of measurement data, suggesting that the exceedances might be
related to background fluctuation. For the exceedances at SR4, SR5, SR6 and
SR7, the measurement results at upstream control stations were lower than the
corresponding Action Levels, suggesting that the background DO level was
already low. |
|
13th June |
10 (SR1, SR2, SR6 &
SR7 during ebb tide and flood tide and SR4 & SR5 during flood) |
0 |
Not
related to site activities as by reviewing the literature data from EPD in
1999 (WM1
& SM5), all exceedances lay within the ranges of
measurement data, suggesting that the exceedances might be related to
background fluctuation. Besides, the measurement results at upstream control
stations were lower than the corresponding Action Levels, suggesting that the
background DO level was already low. |
|
14th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities as by reviewing the literature data from EPD in 1999 (WM1 & SM5), all exceedances (except the exceedance at SR7) lay within the ranges
of measurement data, suggesting that the exceedances might be related to
background fluctuation. For the
exceedance at SR7 during flood tide, the marine water flowed from South to
North during sampling at SR7 which was located upstream from the site.
Therefore the exceedance might be due to background fluctuation. Besides, the exceedance was recorded
again at SR7 during ebb tide, which indicated that the low DO measurement
result might be a localized event at SR7 during the sampling day. |
|
15th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were as low as the said exceedances
(except result at SR2), suggesting the background DO was also low. By reviewing the literature data from EPD in 1999 (WM1), the measurement results at SR2 lay within the ranges of measurement
data, suggesting that the exceedances might be related to background
fluctuation. |
|
18th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were lower than the said exceedances
(except result at SR1 and SR6 during ebb tide). For the exceedances at SR1
and SR6 during ebb tide, the measurement results at upstream control stations
were much lower than the corresponding Action Levels. Hence, the background
DO at the vicinity of study area was also low. |
|
20th June |
10 (SR1, SR2, SR5, SR6 & SR7 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were as low as the said exceedance,
suggesting that the background DO level was also low. |
|
22nd June |
10 (SR1, SR2, SR5, SR6 & SR7 during ebb tide and flood tide) |
0 |
Not related to site activities as the exceedance at SR1, SR2 and SR6 during ebb tide and flood tide and SR5 & SR7 during ebb tide, the measurement results at the upstream control stations were even lower than the said exceedances, suggesting that the background DO was already low. For the exceedances at the bottom level of SR5 and SR7 during flood tide, the measurement results of upstream control stations were lower than the corresponding Action Levels. Moreover, the marine water flowed from South to North during sampling at SR5 and SR7 which was located upstream from the site. Therefore the said exceedance might be due to background fluctuation . |
|
25th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement
results at upstream control stations were as low as the said exceedances
(except the measurement result at SR1 during ebb tide), suggesting the
background DO was also low. For the exceedance at SR1 during ebb tide, it lay
within the range of measurement results collected by EPD in 1999, suggesting
that the low DO might be due background fluctuation. |
|
28th June |
12 (All stations except SR3 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement results at upstream control stations were as low as the said exceedances, suggesting that the background DO level was also low. |
|
29th June |
10 (SR1, SR2, SR6 & SR7 during ebb tide and flood tide and SR4
& SR5 during flood) |
0 |
Not
related to site activities as by reviewing the literature data from EPD in
1999 (WM1
& SM5), all exceedances (except the result at SR7
during flood tide) lay within the ranges of measurement data, suggesting that
the exceedances might be related to background fluctuation. For the
exceedance at SR7 during flood tide, the measurement result at upstream
control stations were lower than the corresponding Action Levels, suggesting
that the background DO level was already low. |
Summary of Exceedances in Turbidity (Depth
Average) in June 2001
|
Monitoring Dates |
No. of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
0 |
0 |
N. A. |
|
4th June |
0 |
0 |
N. A. |
|
6th June |
0 |
0 |
N. A. |
|
11th June |
0 |
0 |
N. A. |
|
13th June |
0 |
0 |
N. A. |
|
14th June |
0 |
0 |
N. A. |
|
15th June |
0 |
0 |
N. A. |
|
18th June |
0 |
0 |
N. A. |
|
20th June |
0 |
0 |
N. A. |
|
22nd June |
0 |
0 |
N. A. |
|
25th June |
0 |
0 |
N. A. |
|
28th June |
0 |
0 |
N. A. |
|
29th June |
0 |
0 |
N. A. |
Summary of Exceedances in Suspended Solids (Depth
Average) in June 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
0 |
0 |
N. A. |
|
4th June |
0 |
2 (SR1& SR2 during flood tide) |
Not related to the site
activities. Based on the on-site
observation made by the sampling team,
no obvious plume migrating from the site area to the said monitoring station
was observed during the course of sampling; and no particular activities were
carried out in the vicinity of the
sampling location. Further, the measurement results on the subsequent sampling were below the Action Levels.
Therefore, the said exceedances might be due
to background fluctuation. |
|
6th June |
0 |
0 |
N. A. |
|
11th June |
0 |
0 |
N. A. |
|
13th June |
0 |
0 |
N. A. |
|
14th June |
0 |
0 |
N. A. |
|
15th June |
1 (SR4 during ebb tide) |
0 |
Not related to the site
activities. Based on the on-site
observation made by the sampling team,
no obvious plume migrating from the site area to the said monitoring station
was observed during the course of sampling; and no particular activities were
carried out in 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. |
|
18th June |
0 |
0 |
N. A. |
|
20th June |
1 (SR6 during flood tide) |
2 (SR1&
SR2 during flood tide) |
Not related to site activities as the SR6 located
at the upstream to the site area during the course of sampling and therefore
the elevated SS result might be associated with the marine water flow from the
southern area of Lamma Island. For
the Limit level exceedances at SR1 and SR2, the measurement result at SR2
(which is located between SR1 and the site) was lower than the result at SR1
therefore the elevated result might be due to background fluctuation. |
|
22nd June |
0 |
1 (SR1 during flood tide) |
Not
related to site activities. This was because the measurement result at SR2
(which is located between SR1 and the site) was much lower than the result at
SR1 therefore the elevated result might be due to background fluctuation. |
|
25th June |
0 |
1 (SR1 during flood tide) |
Not
related to the site activities.
Based on the on-site observation made by the environmental consultant, a
container vessel 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 container vessel
is given in Appendix M. |
|
28th June |
0 |
0 |
N. A. |
|
29th June |
0 |
0 |
N. A. |
Summary of Exceedances in Unionized Ammonia
(Depth Average) in June 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if
any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
9 (SR2, SR5, SR6 & SR7
during ebb tide and flood tide and SR1 during ebb tide) |
0 |
Not related to site
activities as the measurement result at upstream control stations were higher
than the exceedances during ebb tide. On the other hand, by reviewing the literature data from EPD in 1999 (WM1 & SM5), all exceedances during flood tide lay within the ranges of
measurement data, suggesting that the exceedances might be related to
background fluctuation. |
|
4th June |
11 (SR1, SR2, SR5, SR6
& SR7 during ebb tide and flood tide and SR4 during ebb tide) |
0 |
Not related to site
activities as the measurement result at upstream control stations were higher
than the exceedances at SR6 & SR7 during ebb tide and flood tide and SR4
& SR5 during ebb tide. Further, SR5 is upstream
of the site area during flood tide, therefore the elevated NH3 result might be due to background fluctuation. Similarly, SR1 & SR2 are upstream of the site area during ebb tide,
therefore the elevated NH3 result might also be due
to background fluctuation. |
|
6th June |
9 (SR2, SR5, SR6 & SR7
during ebb tide and flood tide and SR4 during ebb tide) |
0 |
Not related to site
activities as the measurement results at the upstream control stations were
even higher than the impact monitoring results,
suggesting that the background concentrations were already high. |
|
11th June |
11 (SR2, SR4, SR5, SR6
& SR7 during ebb tide and flood tide and SR1 during ebb tide) |
0 |
Not related to site activities since the measurement results of the upstream control stations were much higher than the impact stations’ results. |
|
13th June |
10 (SR2, SR4, SR5, SR6
& SR7 during ebb tide and flood tide) |
0 |
Not related to site
activities since the measurement results of
SR6 & SR7 during flood tide and all exceedances during ebb tide were as
high as the measurement results at upstream control stations, suggesting that the background NH3 concentration
was also high. For the exceedances at SR2, SR4 & SR5, the measurement
results of upstream control stations were as high as the corresponding Action
Levels, suggesting that background NH3 concentration was
high. |
|
14th June |
2 (SR2 during ebb tide and
SR5 during flood) |
0 |
Not related to site activities since the measurement results of the upstream control stations were much higher than the impact stations’ results. |
|
15th June |
7 (SR4 during ebb tide and
SR5, SR6 & SR7 during ebb tide and flood tide) |
0 |
Not related to site activities as the measurement results at the upstream control stations were as high as that at the impact stations. |
|
18th June |
7 (SR4 during ebb tide and
SR5, SR6 & SR7 during ebb tide and flood tide) |
0 |
Not related to site activities since the measurement results of the upstream control stations were as high as that at the impact stations except the exceedance at SR4 during ebb tide. For the exceedance at SR4 during ebb tide, the measurement results of upstream control stations were higher than the corresponding Action Levels, suggesting that background NH3 concentration was high. |
|
20th June |
6 (SR4 & SR6 during
ebb tide and SR5 & SR7 during ebb tide and flood tide) |
0 |
Not related to site activities since the measurement results of the upstream control stations were as high as the impact stations’ results. |
|
22nd June |
6 (SR5, SR6 & SR7
during ebb tide and flood tide) |
0 |
Not related to site activities since the measurement results at the upstream control stations were as high as that at the impact stations. |
|
25th June |
3 (SR5 during ebb tide and
flood tide and SR6 during ebb tide) |
0 |
Not related to site activities as by reviewing the literature data
from EPD in 1999 (SM5), all exceedances lay within the ranges of
measurement data, suggesting that the exceedances might be related to
background fluctuation. |
|
28th June |
6 (SR5 & SR6 during
ebb tide and flood tide and SR4 & SR7 during flood) |
0 |
Not related to site activities since the measurement results of the upstream control stations were much higher than that at the impact stations. |
|
29th June |
3 (SR5 during ebb and flood tide & SR6 during ebb tide) |
0 |
Not related to site activities since the measurement results at the upstream control stations were much higher than that at the impact stations. |
Summary of Exceedances in Total Inorganic
Nitrogen (Depth Average) in June 2001
|
Monitoring Dates |
Number of Exceedances |
Investigation Findings (if any) |
|
|
Action Level |
Limit Level |
||
|
1st June |
2 (SR1 during ebb tide and flood tide) |
2 (SR2 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at SR1 and SR2 during flood tide. For SR2 during ebb
tide, based on the on-site observation made by the sampling team, no particular activities were carried
out in the vicinity of the
sampling location which resulted in the elevated measurement result at SR2.
Further, the measurement result on subsequent sampling was below the said
exceedance. Therefore, the said exceedance might be due to background fluctuation. |
|
4th June |
1 (SR1 during ebb tide) |
11 (SR1 during flood tide
and 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 higher than the
impact stations’ results during ebb tide. For the exceedances at SR4, SR5,
SR6 & SR7 during flood tide, by reviewing the
literature data from EPD in 1999 (WM1 & SM5),
all exceedances lay within the ranges of measurement data, suggesting that
the exceedances might be related to background fluctuation. Besides, no noticeable activities
were observed from the direction of construction site which might result in
the elevated TIN measurement. Therefore, the exceedances at SR1 and SR2
during flood tide might be due to background fluctuation rather than site
activities. |
|
6th June |
0 |
12 (All stations except SR3 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at SR1, SR4 & SR5 during ebb tide and SR6 & SR7 during ebb tide and flood tide. For the exceedances at SR5 during flood tide and SR2 during ebb tide, the measurement results at upstream control stations were higher than the corresponding Limit Levels. Therefore, the said exceedances might be due to background fluctuation. |
|
11th June |
0 |
12 (All stations except SR3 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at SR1, SR4 & SR7. For the exceedances at SR2, SR5 & SR6, the measurement results at upstream control stations were higher than the corresponding Limit Levels. Therefore, the said exceedances might be due to background fluctuation. |
|
13th June |
0 |
12 (All stations except SR3 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at SR1 & SR7 during flood tide and all exceedances during ebb tide. For the exceedances at SR2, SR4, SR5 & SR6 during flood tide, the measurement results at upstream control stations were higher than the corresponding Limit Levels. Therefore, the said exceedances might be due to background fluctuation. |
|
14th June |
0 |
12 (All stations except SR3 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at the impact stations. |
|
15th June |
1 (SR1 during ebb tide) |
11 (SR1 during flood tide
and SR2, SR4, SR5, SR6 & SR7 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were as high as that at the impact stations. |
|
18th June |
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 at the upstream control stations were higher than that at the impact stations. |
|
20th June |
1 (SR1 during flood tide) |
11 (SR1 during ebb tide
and SR2, SR4, SR5, SR6 & SR7 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were as high as that at SR1, SR2, SR6 & SR7. For the exceedances at SR4 & SR5, the measurement results at upstream control stations were much higher than the corresponding Limit Levels. Therefore, the said exceedances might be due to background fluctuation. |
|
22nd June |
1 (SR1 during flood tide) |
11 (SR1 during ebb tide
and 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 as high as that at SR1, SR2, SR6 & SR7. For the exceedances at SR4 & SR5, the measurement results at upstream control stations were much higher than the corresponding Limit Levels. Therefore, the said exceedances might be due to background fluctuation. |
|
25th June |
1 (SR1 during flood tide) |
11 (SR1 during ebb tide
and SR2, SR4, SR5, SR6 & SR7 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were higher than that at the impact stations. |
|
28th June |
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 at the upstream control stations were as high as those at all stations except at SR2 during ebb tide. For the exceedances at SR2 during ebb tide, the measurement results at upstream control stations were much higher than the corresponding Limit Level. Therefore, the said exceedances might be due to background fluctuation. |
|
29th June |
1 (SR1 during ebb tide) |
11 (SR1 during flood tide
and SR2, SR4, SR5, SR6 & SR7 during ebb tide and flood tide) |
Not related to site activities since the measurement results at the upstream control stations were as high as that at the impact stations. |
There were three hundred and nine (309) cases of Action level exceedance
and one hundred and forty-two (142) cases of Limit Level exceedance for water
quality in the reporting month.
238 out of 451 cases of action/limit level exceedances were contributed
by TIN and NH3-N while 205 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 monitoring locations close to Lamma Island, all
the measurement results exceeding Action/Limit Levels lay within the range of
EPD’s data. This showed that the
Action/Limit level as established by the baseline monitoring work which was
carried out during cooler season, was not appropriate for the current water
body condition.
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 revise the
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 June 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) |
01/06/01-30/06/01 |
0 |
0 |
|
|
|
2 |
Ambient TSP (1-hour) |
01/06/01-30/06/01 |
0 |
0 |
|
|
|
Noise |
||||||
|
1 |
Noise level at the critical NSR’s predicted by the noise alarm monitoring system |
01/06/01-30/06/01 |
0 |
0 |
|
|
|
2 |
Manual noise monitoring at the Pak Kok Tsui residences |
01/06/01-30/06/01 |
NA |
NA |
Construction of transmission system not yet commenced. |
|
|
Water |
||||||
|
1 |
DO (Surface & Middle) |
01/06/01-30/06/01 |
76 |
0 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
|
2 |
DO (Bottom) |
01/06/01-30/06/01 |
129 |
0 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
|
3 |
SS |
01/06/01-30/06/01 |
2 |
6 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
|
4 |
Turbidity |
01/06/01-30/06/01 |
0 |
0 |
|
|
|
5 |
NH3-N |
01/06/01-30/06/01 |
90 |
0 |
The exceedances were considered not related to the construction activities. Please refer to section 4 of the report for details. |
|
|
6 |
TIN |
01/06/01-30/06/01 |
12 |
136 |
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 June 2001 are shown in Table 5.2.
Table
5.2 Estimated Amounts of Waste
Generated in June 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 1,018,674m3. No filling took place.
EPD officials from Urban Environmental Assessment Group have inspected
the construction site on 20th June 2001. They were generally satisfied with the environmental performance of the Project.
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
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 site. |
Valid |
|
Construction Noise Permit |
GW-UW0109-01 GW-UW0180-01 GW-UW0256-01 |
02/04/01 08/05/01 29/06/01 |
01/10/01 18/10/01 07/12/01 |
4 derrick barges, 4 dredger grabs and 6 tug boats for 0700 to 2300
& holiday 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 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) |
Valid Superseded
by GW-UW0256-01 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 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 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 June 2001.
Table 5.4 Environmental
Complaints / Enquiries Received in June 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 actions to ensure the seawater quality.
· To provide routine inspection and necessary maintenance for the silt curtains.
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.
Except the two marine water monitoring works on 8th June 2001 and 27th June 2001 rescheduled due to adverse weather conditions, 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 451 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 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 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.
