|
Expansion of Hong Kong International Airport into a Three-Runway System |
|
Construction Phase Monthly EM&A Report No.19 (For July 2017) |
Executive Summary
The “Expansion of Hong Kong International Airport into a Three-Runway System” (the Project) serves to meet the future air traffic demands at Hong Kong International Airport (HKIA). On 7 November 2014, the Environmental Impact Assessment (EIA) Report (Register No.: AEIAR-185/2014) for the Project was approved and an Environmental Permit (EP) (Permit No.: EP-489/2014) was issued for the construction and operation of the Project.
Airport Authority Hong Kong (AAHK) commissioned Mott MacDonald Hong Kong Limited (MMHK) to undertake the role of Environmental Team (ET) for carrying out the Environmental Monitoring & Audit (EM&A) works during the construction phase of the Project in accordance with the Updated EM&A Manual (the Manual).
This is the 19th Construction Phase Monthly EM&A Report for the Project which summarizes the monitoring results and audit findings of the EM&A programme during the reporting period from 1 to 31 July 2017.
Key Activities in the Reporting Period
The key activities of the Project carried out in the reporting period included deep cement mixing (DCM) works and trials, laying of sand blanket and geotextile, site preparation works, site office establishment and horizontal directional drilling (HDD) works.
EM&A Activities Conducted in the Reporting Period
The monthly EM&A programme was undertaken in accordance with the Manual of the Project. During the reporting period, the ET conducted 30 sets of construction dust measurements, 20 sets of construction noise measurements, 13 events of water quality measurements, 2 complete sets of small vessel line-transect surveys and 5 days of land-based theodolite tracking survey effort for Chinese White Dolphin (CWD) monitoring and waste monitoring. Construction works on Sheung Sha Chau Island was suspended during the ardeid’s breeding season (between April and July). The ecological monitoring is therefore suspended.
Weekly site inspections of the construction works were carried out by the ET to audit the implementation of proper environmental pollution control and mitigation measures for the Project. Bi-weekly site inspections were also conducted by the Independent Environmental Checker (IEC). Observations have been recorded in the site inspection checklists and provided to the contractors together with the appropriate follow-up actions where necessary.
On the implementation of Marine Mammal Watching Plan (MMWP), dolphin observers were deployed by the contractors for laying of open sea silt curtain and laying of silt curtains for sand blanket in accordance with the plan. On the implementation of Dolphin Exclusion Zone (DEZ) Plan, dolphin observers at 12 to 15 dolphin observation stations were deployed for continuous monitoring of the DEZ by all contractors for DCM works in accordance with the DEZ Plan. Trainings for the proposed dolphin observers were provided by the ET prior to the aforementioned works, with the training records kept by the ET. From the contractors’ MMWP observation records and DEZ monitoring records, no dolphin or other marine mammals were observed within or around the silt curtains, whilst there were two records of dolphin sighting within the DEZs of DCM works in this reporting month. Audits of acoustic decoupling for construction vessels were also carried out by the ET.
On the implementation of the Marine Travel Routes and Management Plan for High Speed Ferries of SkyPier (the SkyPier Plan), the daily movements of all SkyPier high speed ferries (HSFs) in July 2017 were in the range of 20 to 93 daily movements, which are within the maximum daily cap of 125 daily movements. A total of 846 HSF movements under the SkyPier Plan were recorded in the reporting period. All HSFs had travelled through the Speed Control Zone (SCZ) with average speeds under 15 knots (9.9 to 14.0 knots), which were in compliance with the SkyPier Plan. One ferry movement with minor deviation from the diverted route is under investigation by ET. The investigation result will be presented in the next monthly EM&A report. In summary, the ET and IEC have audited the HSF movements against the SkyPier Plan and conducted follow up investigation or actions accordingly.
On the implementation of the Marine Travel Routes and Management Plan for Construction and Associated Vessel (MTRMP-CAV), the Marine Surveillance System (MSS) automatically recorded the deviation case such as speeding, entering no entry zone, not traveling through the designated gate. ET conducted checking to ensure the MSS records all deviation cases accurately. Training has been provided for the concerned skippers to facilitate them in familiarising with the requirements of the MTRMP-CAV. Deviations including speeding in the works area, entry from non-designated gates, and entering no-entry zones were reviewed by ET. All the concerned captains were reminded by the contractor’s Marine Traffic Control Centre (MTCC) representative to comply with the requirements of the MTRMP-CAV. ET reminded contractors that all vessels shall avoid entering the no-entry zone, in particular the Brothers Marine Park. 3-month rolling programmes for construction vessel activities, which ensures the proposed vessels are necessary and minimal through good planning, were also received from contractors.
Results of Impact Monitoring
The monitoring works for construction dust, construction noise, water quality, construction waste, and CWD were conducted during the reporting period in accordance with the Manual.
No exceedance of the Action or Limit Levels in relation to construction dust, construction noise, construction waste, and CWD monitoring was recorded in the reporting month.
The water quality monitoring results for turbidity, total alkalinity, and chromium obtained during the reporting period did not trigger their corresponding Action and Limit Levels stipulated in the EM&A programme for triggering the relevant investigation and follow-up procedures under the programme if being exceeded. For DO, SS, and nickel, some of the testing results exceeded the relevant Action or Limit Levels, and the corresponding investigations were conducted accordingly. The investigation findings concluded that the exceedances were not due to the Project.
Summary of Upcoming Key Issues
Advanced Works:
Contract P560 (R) Aviation Fuel Pipeline Diversion Works
● HDD works; and
● Stockpiling
of excavated materials from HDD operation.
DCM Works:
Contract 3201 to 3205 DCM Works
● Laying of sand blanket; and
● DCM works and trials.
Reclamation Works:
Contract 3206 Main Reclamation Works
● Site office establishment; and
● Laying of
sand blanket.
Terminal 2 Expansion Works:
Contract 3501 Antenna Farm and Sewage Pumping Station
● Site formation and excavation works.
Contract 3502 Terminal 2 APM Depot Modification Works
● Removal of
existing concrete.
Airfield Works:
Contract 3301 North Runway Crossover Taxiway
● CLP cable
ducting work.
The key environmental issues will be associated with construction dust, construction noise, water quality, construction waste management, CWD and terrestrial ecology on Sheung Sha Chau. The implementation of required mitigation measures by the contractor will be monitored by the ET.
|
|
|
|
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Dolphin Exclusion Zone Monitoring by Dolphin Observer |
Chemical Spill Drill conducted by the Contractor |
Skipper Training |
Summary Table
The following table summarizes the key findings of the EM&A programme during the reporting period:
|
|
Yes |
No |
Details |
Analysis / Recommendation / Remedial Actions |
|
Exceedance of Limit Level^ |
|
ü |
No exceedance of project-related limit level was recorded. |
Nil |
|
Exceedance of Action Level^ |
|
ü |
No exceedance of project-related action level was recorded. |
Nil |
|
Complaints Received |
|
ü |
No construction activities related complaints were received. |
Nil |
|
Notification of any summons and status of prosecutions |
|
ü |
No notifications of summons or prosecution were received. |
Nil |
|
Changes that affect the EM&A |
|
ü |
There were no changes to the construction works that may affect the EM&A |
Nil |
Remarks: ^Only exceedance of Action or Limit Level related to Project works is counted as Breaches of Action or Limit Level.
1
Introduction
1.1
Background
On 7 November 2014, the Environmental Impact Assessment (EIA) Report (Register No.: AEIAR-185/2014) for the “Expansion of Hong Kong International Airport into a Three-Runway System” (the Project) was approved and an Environmental Permit (EP) (Permit No.: EP-489/2014) was issued for the construction and operation of the Project.
Airport Authority Hong Kong (AAHK) commissioned Mott MacDonald Hong Kong Limited (MMHK) to undertake the role of Environmental Team (ET) for carrying out the Environmental Monitoring & Audit (EM&A) works during the construction phase of the Project in accordance with the Updated EM&A Manual (the Manual) submitted under EP Condition 3.1. The Manual is available on the Project’s dedicated website (accessible at: http://env.threerunwaysystem.com/en/index.html). AECOM Asia Company Limited (AECOM) was employed by AAHK as the Independent Environmental Checker (IEC) for the Project.
The Project covers the expansion of the existing airport into a three-runway system (3RS) with key project components comprising land formation of about 650 ha and all associated facilities and infrastructure including taxiways, aprons, aircraft stands, a passenger concourse, an expanded Terminal 2, all related airside and landside works and associated ancillary and supporting facilities. The existing submarine aviation fuel pipelines and submarine power cables also require diversion as part of the works.
Construction of the Project is to proceed in the general order of diversion of the submarine aviation fuel pipelines, diversion of the submarine power cables, land formation, and construction of infrastructure, followed by construction of superstructures.
The updated overall phasing programme of all construction works was presented in Appendix A of the Construction Phase Monthly EM&A Report No. 7 and the contract information was presented in Appendix A.
1.2
Scope of this Report
This is the 19th Construction Phase Monthly EM&A Report for the Project which summarizes the key findings of the EM&A programme during the reporting period from 1 to 31 July 2017.
1.3
Project Organisation
The Project’s organization structure presented in Appendix B of the Construction Phase Monthly EM&A Report No.1 remained unchanged during the reporting month. Contact details of the key personnel have been updated and is presented in Table 1.1.
Table 1.1: Contact Information of Key Personnel
|
Party |
Position |
Name |
Telephone |
|
Project Manager’s Representative (Airport Authority Hong Kong) |
Principal Manager, Environment |
Lawrence Tsui |
2183 2734 |
|
Environmental Team (ET) (Mott MacDonald Hong Kong Limited) |
Environmental Team Leader |
Terence Kong |
2828 5919 |
|
|
Deputy Environmental Team Leader |
Heidi Yu |
2828 5704 |
|
|
Deputy Environmental Team Leader |
Keith Chau |
2972 1721 |
|
Independent Environmental Checker (IEC) (AECOM Asia Company Limited) |
Independent Environmental Checker |
Jackel Law |
3922 9376
|
|
|
Deputy Independent Environmental Checker |
Joanne Tsoi |
3922 9423 |
|
Advanced Works: |
|
|
|
|
Contract P560(R) Aviation Fuel Pipeline Diversion Works (Langfang Huayuan Mechanical and Electrical Engineering Co., Ltd.) |
Project Manager
|
Wei Shih
|
2117 0566
|
|
Environmental Officer |
Lyn Lau
|
5172 6543
|
|
|
DCM Works: |
|
|
|
|
Contract 3201 DCM (Package 1) (Penta-Ocean-China State-Dong-Ah Joint Venture) |
Project Director
|
Tsugunari Suzuki
|
9178 9689 |
|
|
Environmental Officer
|
Alan Tam
|
6119 3107 |
|
Contract 3202 DCM (Package 2) (Samsung-BuildKing Joint Venture) |
Project Manager |
Ilkwon Nam
|
9643 3117 |
|
|
Environmental Officer
|
Dickson Mak
|
9525 8408 |
|
Contract 3203 DCM (Package 3) (Sambo E&C Co., Ltd) |
Project Manager
|
Eric Kan
|
9014 6758 |
|
|
Environmental Officer
|
Calvin Leung
|
9203 5820 |
|
Contract 3204 DCM (Package 4) (CRBC-SAMBO Joint Venture) |
Project Manager |
Kyung-Sik Yoo
|
9683 8697
|
|
|
Environmental Officer |
Kanny Cho |
6799 8226 |
|
Contract 3205 DCM (Package 5) (Bachy Soletanche - Sambo Joint Venture) |
Deputy Project Director |
Min Park |
9683 0765 |
|
|
Environmental Officer |
Margaret Chung |
9130 3696 |
|
Reclamation Works: |
|
|
|
|
Contract 3206 (ZHEC-CCCC-CDC Joint Venture) |
Project Manager |
Kim Chuan Lim
|
3693 2288 |
|
|
Environmental Officer |
Kwai Fung Wong |
3693 2252 |
|
Terminal 2 Expansion Works: |
|
|
|
|
Contract 3501 Antenna Farm and Sewage Pumping Station (Build King Construction Ltd.) |
Project Manager
|
Osbert Sit
|
9079 7030
|
1.4
Summary of
Construction Works
The key activities of the Project carried out in the reporting period included DCM works and trials, laying of sand blanket and geotextile, site preparation works, site office establishment and HDD works.
1.5
Summary of EM&A Programme Requirements
The status for all environmental aspects is presented in Table 1.2. The EM&A requirements remained unchanged during the reporting period and details can be referred to Table 1.2 of the Construction Phase Monthly EM&A Report No. 1.
Table 1.2: Summary of status for all environmental aspects under the Updated EM&A Manual
|
Parameters |
Status |
|
Air Quality |
|
|
Baseline Monitoring |
The baseline air quality monitoring result has been reported in Baseline Monitoring Report and submitted to EPD under EP Condition 3.4. |
|
Impact Monitoring |
On-going |
|
Noise |
|
|
Baseline Monitoring |
The baseline noise monitoring result has been reported in Baseline Monitoring Report and submitted to EPD under EP Condition 3.4. |
|
Impact Monitoring |
On-going |
|
Water Quality |
|
|
General Baseline Water Quality Monitoring for reclamation, water jetting and field joint works |
The baseline water quality monitoring result has been reported in Baseline Water Quality Monitoring Report and submitted to EPD under EP Condition 3.4. |
|
General Impact Water Quality Monitoring for reclamation, water jetting and field joint works |
On-going |
|
Initial Intensive Deep Cement Mixing (DCM) Water Quality Monitoring |
Completed in May 2017 and data analysis in-progress. |
|
Early/ Regular DCM Water Quality Monitoring |
On-going |
|
Waste Management |
|
|
Waste Monitoring |
On-going |
|
Land Contamination |
|
|
Supplementary Contamination Assessment Plan (CAP) |
To be submitted with the relevant construction works. |
|
Contamination Assessment Report (CAR) for Golf Course |
The CAR for Golf Course was submitted to EPD. |
|
Terrestrial Ecology |
|
|
Pre-construction Egretry Survey Plan |
The Egretry Survey Plan was submitted and approved by EPD under EP Condition 2.14. |
|
Ecological Monitoring |
Construction works on Sheung Sha Chau Island was suspended during the ardeid’s breeding season (between April and July). The ecological monitoring is therefore suspended. |
|
Marine Ecology |
|
|
Pre-Construction Phase Coral Dive Survey |
The Coral Translocation Plan was submitted and approved by EPD under EP Condition 2.12. |
|
Coral Translocation |
The coral translocation was completed. |
|
Post-Translocation Coral Monitoring |
On-going |
|
Chinese White Dolphins (CWD) |
|
|
Vessel Survey, Land-based Theodolite Tracking and Passive Acoustic Monitoring (PAM) |
|
|
Baseline Monitoring |
Baseline CWD results were reported in the CWD Baseline Monitoring Report and submitted to EPD in accordance with EP Condition 3.4. |
|
Impact Monitoring |
On-going |
|
Landscape & Visual |
|
|
Baseline Monitoring |
The baseline landscape & visual monitoring result has been reported in Baseline Monitoring Report and submitted to EPD under EP Condition 3.4. |
|
Impact Monitoring |
On-going |
|
Environmental Auditing |
|
|
Regular site inspection |
On-going |
|
Marine Mammal Watching Plan (MMWP) implementation measures |
On-going |
|
Dolphin Exclusion Zone Plan (DEZP) implementation measures |
On-going |
|
SkyPier High Speed Ferries (HSF) implementation measures |
On-going |
|
Construction and Associated Vessels Implementation measures |
On-going |
|
Complaint Hotline and Email channel |
On-going |
|
Environmental Log Book |
On-going |
Taking into account the construction works in this reporting month, impact monitoring of air quality, noise, water quality, waste management and CWD were carried out in the reporting month.
The EM&A programme also involved weekly site inspections and related auditing conducted by the ET for checking the implementation of the required environmental mitigation measures recommended in the approved EIA Report. In order to enhance environmental awareness and closely monitor the environmental performance of the contractors, environmental briefings and regular environmental management meetings were conducted.
The EM&A programme has been following the recommendations presented in the approved EIA Report and the Manual. A summary of implementation status of the environmental mitigation measures for the construction phase of the Project during the reporting period is provided in Appendix B.
2 Air Quality Monitoring
2.1
Monitoring Stations
Air quality monitoring was conducted at 2 representative monitoring stations in the vicinity of air sensitive receivers in Tung Chung and villages in North Lantau in accordance with the Manual. Table 2.1 describes the details of the monitoring stations. Figure 2.1 shows the locations of the monitoring stations.
Table 2.1: Locations of Impact Air Quality Monitoring Stations
|
Monitoring Station |
Location |
|
AR1A |
Man Tung Road Park |
|
AR2 |
Village House at Tin Sum |
2.2
Monitoring
Requirements and Schedule
In accordance with the Manual, baseline 1-hour total suspended particulate (TSP) levels at the two air quality monitoring stations were established as presented in the Baseline Monitoring Report. Impact 1-hour TSP monitoring was conducted for three times every 6 days. The Action and Limit Levels of the air quality monitoring stipulated in the EM&A programme for triggering the relevant investigation and follow-up procedures under the programme are provided in Table 2.2.
The air quality monitoring schedule involved in the reporting period is provided in Appendix C.
Table 2.2: Action and Limit Levels for 1-hour TSP
|
Monitoring Station |
Action Level (mg/m3) |
Limit Level (mg/m3) |
|
AR1A |
306 |
500 |
|
AR2 |
298 |
2.3
Monitoring Equipment
Portable direct reading dust meter was used to carry out the 1-hour TSP monitoring. Details of equipment are given in Table 2.3.
Table 2.3: Air Quality Monitoring Equipment
|
Equipment |
Brand and Model |
Last Calibration Date |
|
Portable direct reading dust meter (Laser dust monitor) |
SIBATA LD-3B-002 (Serial No. 974350) |
26 Oct 2016 |
2.4
Monitoring
Methodology
2.4.1
Measuring Procedure
The measurement procedures involved in the impact 1-hr TSP monitoring can be summarised as follows:
a. The portable direct reading dust meter was mounted on a tripod at a height of 1.2 m above the ground.
b. Prior to the measurement, the equipment was set up for 1 minute span check and 6 second background check.
c. The one hour dust measurement was started. Site conditions and dust sources at the nearby area were recorded on a record sheet.
d. When the measurement completed, the “Count” reading per hour was recorded for result calculation.
2.4.2
Maintenance and Calibration
The portable direct reading dust meter is calibrated every year against high volume sampler (HVS) to check the validity and accuracy of the results measured by direct reading method. The calibration certificates of the portable direct reading dust meter and calibration record of the HVS provided in Appendix B of the Construction Phase Monthly EM&A Report No.11 are still valid. Any updates of calibration certificates will be reported in the Monthly EM&A report if necessary.
2.5
Analysis and
Interpretation of Monitoring Results
The monitoring results for 1-hour TSP are summarized in Table 2.4. Detailed impact monitoring results are presented in Appendix D.
Table 2.4: Summary of 1-hour TSP Monitoring Results
|
Monitoring Station |
1-hr TSP Concentration Range (mg/m3) |
Action Level (mg/m3) |
Limit Level (mg/m3) |
|
AR1A |
9 – 20 |
306 |
500 |
|
AR2 |
9 – 23 |
298 |
No exceedance of the Action or Limit Level was recorded at all monitoring stations in the reporting period.
General meteorological conditions throughout the impact monitoring period were recorded. Wind data including wind speed and wind direction for each monitoring day were collected from the Chek Lap Kok Wind Station.
3
Noise Monitoring
3.1
Monitoring Stations
Noise monitoring was conducted at 5 representative monitoring stations in the vicinity of noise sensitive receivers in Tung Chung and villages in North Lantau in accordance with the Manual. Figure 2.1 shows the locations of the monitoring stations and these are described in Table 3.1 below. As described in Section 4.3.3 of the Manual, monitoring at NM2 will commence when the future residential buildings in Tung Chung West Development become occupied.
Table 3.1: Locations of Impact Noise Monitoring Stations
|
Monitoring Station |
Location |
Type of measurement |
|
NM1A |
Man Tung Road Park |
Free field |
|
NM2(1) |
Tung Chung West Development |
To be determined |
|
NM3A |
Site Office |
Facade |
|
NM4 |
Ching Chung Hau Po Woon Primary School |
Free field |
|
NM5 |
Village House in Tin Sum |
Free field |
|
NM6 |
House No. 1, Sha Lo Wan |
Free field |
Note: (1) As described in Section 4.3.3 of the Manual, noise monitoring at NM2 will only commence after occupation of the future Tung Chung West Development.
3.2
Monitoring Requirements and Schedule
In accordance with the Manual, baseline noise levels at the noise monitoring stations were established as presented in the Baseline Monitoring Report. Impact noise monitoring was conducted once per week in the form of 30-minute measurements of Leq, L10 and L90 levels recorded at each monitoring station between 0700 and 1900 on normal weekdays. The Action and Limit Levels of the noise monitoring stipulated in the EM&A programme for triggering the relevant investigation and follow-up procedures under the programme are provided in Table 3.2. The construction noise monitoring schedule involved in the reporting period is provided in Appendix C.
Table 3.2: Action and Limit Levels for Construction Noise
|
Monitoring Stations |
Time Period |
Action Level |
Limit Level, Leq(30mins) dB(A) |
|
NM1A, NM2, NM3A, NM4, NM5 and NM6 |
0700-1900 hours on normal weekdays |
When one documented complaint is received from any one of the sensitive receivers |
75 dB(A)(i) |
Note: (i) Reduced to 70dB(A) for school and 65dB(A) during school examination periods.
3.3
Monitoring
Equipment
Noise monitoring was performed using sound level meter at each designated monitoring station. The sound level meters deployed comply with the International Electrotechnical Commission Publications 651:1979 (Type 1) and 804:1985 (Type 1) specifications. Acoustic calibrator was used to check the sound level meters by a known sound pressure level for field measurement. Details of equipment are given in Table 3.3.
Table 3.3: Noise Monitoring Equipment
|
Equipment |
Brand and Model |
Last Calibration Date |
|
|
Integrated Sound Level Meter |
B&K 2238 (Serial No. 2800932) |
17 Jul 2017 |
|
|
B&K 2238 (Serial No. 2381580) |
8 Sep 2016 |
||
|
|
|||
|
Acoustic Calibrator |
B&K 4231 (Serial No. 3003246) |
16 May 2017 |
|
|
B&K 4231 (Serial No. 3004068) |
17 Jul 2017 |
||
3.4
Monitoring
Methodology
3.4.1
Monitoring Procedure
The monitoring procedures involved in the noise impact monitoring can be summarised as follows:
a. The sound level meter was set on a tripod at least a height of 1.2 m above the ground for free-field measurements at monitoring stations NM1A, NM4, NM5 and NM6. A correction of +3 dB(A) was applied to the free field measurements.
b. Façade measurements were made at the monitoring station NM3A.
c. Parameters such as frequency weighting, time weighting and measurement time were set.
d. Prior to and after each noise measurement, the meter was calibrated using the acoustic calibrator. If the difference in the calibration level before and after measurement was more than 1 dB(A), the measurement would be considered invalid and repeat of noise measurement would be required after re-calibration or repair of the equipment.
e. During the monitoring period, Leq, L10 and L90 were recorded. In addition, site conditions and noise sources were recorded on a record sheet.
f. Noise measurement results were corrected with reference to the baseline monitoring levels.
g. Observations were recorded when high intrusive noise (e.g. dog barking, helicopter noise) was observed during the monitoring.
3.4.2
Maintenance and Calibration
The maintenance and calibration procedures are summarised below:
a. The microphone head of the sound level meter was cleaned with soft cloth at regular intervals.
b. The meter and calibrator were sent to the supplier or laboratory accredited under Hong Kong Laboratory Accreditation Scheme (HOKLAS) to check and calibrate at yearly intervals.
Calibration certificates of the sound level meters and acoustic calibrators used in the noise monitoring provided in Appendix B of the Construction Phase Monthly EM&A Report No. 9 and Appendix D of the Construction Phase Monthly EM&A Report No. 17 are still valid. The equipment calibrated in July 2017 is provided in Appendix E.
3.5
Analysis and Interpretation of Monitoring Results
The construction noise monitoring results are summarized in Table 3.4 and the detailed monitoring data are provided in Appendix D.
Table 3.4: Summary of Construction Noise Monitoring Results
|
Monitoring Station |
Noise Level Range, dB(A) Leq (30 mins) |
Limit Level, dB(A) Leq (30 mins) |
|
NM1A(i) |
71 – 72 |
75 |
|
NM3A |
57 – 63 |
75 |
|
NM4(i) |
64 – 65 |
70(ii) |
|
NM5(i) |
57 – 67 |
75 |
|
NM6(i) |
62 – 73 |
75 |
Note: (i) +3 dB(A) Façade correction included;
(ii) Reduced to 65 dB(A) during school examination periods at NM4. No school examination took place in the reporting period.
As the construction activities were far away from the monitoring stations, major sources of noise dominating the monitoring stations observed during the construction noise impact monitoring were road traffic and helicopter noise at NM1A, helicopter and aircraft noise at NM3A, road traffic, aircraft, and helicopter noise at NM4, aircraft and helicopter noise at NM5, and insect, aircraft, and marine vessel noise at NM6 in this reporting month.
No exceedance of the Action or Limit Level was recorded at all monitoring stations in the reporting period.
4 Water Quality Monitoring
4.1
Monitoring Stations
Water quality monitoring was conducted at a total of 22 water quality monitoring stations, comprising 12 impact (IM) stations, 7 sensitive receiver (SR) stations and 3 control stations in the vicinity of water quality sensitive receivers around the airport island in accordance with the Manual. Table 4.1 describes the details of the monitoring stations. Figure 3.1 shows the locations of the monitoring stations.
Table 4.1: Monitoring Locations and Parameters for Impact Water Quality Monitoring
|
Monitoring Stations |
Description |
Coordinates |
Parameters |
|
|
Easting |
Northing |
|||
|
C1 |
Control |
804247 |
815620 |
DO, pH, Temperature, Salinity, Turbidity, SS, Total Alkalinity, Heavy Metals(2) |
|
C2 |
Control |
806945 |
825682 |
|
|
C3(3) |
Control |
817803 |
822109 |
|
|
IM1 |
Impact |
806458 |
818351 |
|
|
IM2 |
Impact |
806193 |
818852 |
|
|
IM3 |
Impact |
806019 |
819411 |
|
|
IM4 |
Impact |
805039 |
819570 |
|
|
IM5 |
Impact |
804924 |
820564 |
|
|
IM6 |
Impact |
805828 |
821060 |
|
|
IM7 |
Impact |
806835 |
821349 |
|
|
IM8 |
Impact |
807838 |
821695 |
|
|
IM9 |
Impact |
808811 |
822094 |
|
|
IM10 |
Impact |
809838 |
822240 |
|
|
IM11 |
Impact |
810545 |
821501 |
|
|
IM12 |
Impact |
811519 |
821162 |
|
|
SR1(1) |
Future Hong Kong-Zhuhai-Macao Bridge Hong Kong Boundary Crossing Facilities (HKBCF) Seawater Intake for cooling |
812586 |
820069 |
DO, pH, Temperature, Salinity, Turbidity, SS
|
|
SR2(3) |
Planned marine park / hard corals at The Brothers / Tai Mo To |
814166 |
821463 |
|
|
SR3 |
Sha Chau and Lung Kwu Chau Marine Park / fishing and spawning grounds in North Lantau |
807571 |
822147 |
|
|
SR4A |
Sha Lo Wan |
807810 |
817189 |
|
|
SR5A |
San Tau Beach SSSI |
810696 |
816593 |
|
|
SR6 |
Tai Ho Bay, Near Tai Ho Stream SSSI |
814663 |
817899 |
|
|
SR7 |
Ma Wan Fish Culture Zone (FCZ) |
823742 |
823636 |
|
|
SR8(4) |
Seawater Intake for cooling at Hong Kong International Airport (East) |
811418 (from July 2017 onwards) |
820246 |
|
Notes:
(1) The seawater intakes of SR1 for the future HKBCF is not yet in operation, hence no water quality impact monitoring was conducted at this station. The future permanent location for SR1 during impact monitoring is subject to finalisation after the HKBCF seawater is commissioned.
(2) Details of selection criteria for the two heavy metals for early regular DCM monitoring refer to the Detailed Plan on Deep Cement Mixing available on the dedicated 3RS website (http://env.threerunwaysystem.com/en/ep-submissions.html). DCM specific water quality monitoring parameters (total alkalinity and heavy metals) were only conducted at C1 to C3, SR2, and IM1 to IM12
(3) According to the Baseline Water Quality Monitoring Report, C3 station is not adequately representative as a control station of impact/ SR stations during the flood tide. The control reference has been changed from C3 to SR2 from 1 September 2016 onwards.
(4) The monitoring location for SR8 is subject to further changes due to silt curtain arrangements and the progressive relocation of this seawater intake.
4.2
Monitoring Requirements and Schedule
In accordance with the Manual, baseline water quality levels at the abovementioned representative water quality monitoring stations were established as presented in the Baseline Water Quality Monitoring Report.
General water quality monitoring and early regular DCM water quality monitoring were conducted three days per week, at mid-flood and mid-ebb tides, at the 22 water quality monitoring stations during the reporting period. The sea conditions varied from calm to moderate, and the weather conditions varied from sunny to rainy during the monitoring period.
The water quality monitoring schedule for the reporting period is updated and provided in Appendix C.
4.1.1 Action and Limit Levels for Water Quality Monitoring
The Action and Limit Levels for general water quality monitoring and regular DCM monitoring stipulated in the EM&A programme for triggering the relevant investigation and follow-up procedures under the programme are presented in Table 4.2. The control and impact stations during flood tide and ebb tide for general water quality monitoring and regular DCM monitoring are presented in Table 4.3.
Table 4.2: Action and Limit Levels for General Water Quality Monitoring and Regular DCM Monitoring
|
Parameters |
Action Level (AL) |
Limit Level (LL) |
||
|
Action and Limit Levels for general water quality monitoring and regular DCM monitoring (excluding SR1& SR8) |
||||
|
DO in mg/L (Surface, Middle & Bottom) |
Surface and Middle 4.5 mg/L |
Surface and Middle 4.1 mg/L 5 mg/L for Fish Culture Zone (SR7) only |
||
|
Bottom 3.4 mg/L |
Bottom 2.7 mg/L |
|||
|
Suspended Solids (SS) in mg/L |
23 |
or 120% of upstream control station at the same tide of the same day, whichever is higher |
37 |
or 130% of upstream control station at the same tide of the same day, whichever is higher |
|
Turbidity in NTU |
22.6 |
36.1 |
||
|
Total Alkalinity in ppm |
95 |
99 |
||
|
Representative Heavy Metals for early regular DCM monitoring (Chromium) |
0.2 |
0.2 |
||
|
Representative Heavy Metals for early regular DCM monitoring (Nickel) |
3.2 |
|
3.6 |
|
|
Action and Limit Levels SR1 |
|
|
|
|
|
SS (mg/l) |
To be determined prior to its commissioning |
To be determined prior to its commissioning |
||
|
Action and Limit Levels SR8 |
|
|
|
|
|
SS (mg/l) |
52 |
|
60 |
|
Notes:
(1) For DO measurement, non-compliance occurs when monitoring result is lower than the limits.
(2)For parameters other than DO, non-compliance of water quality results when monitoring results is higher than the limits.
(3)Depth-averaged results are used unless specified otherwise.
(4)Details of selection criteria for the two heavy metals for early regular DCM monitoring refer to the Detailed Plan on Deep Cement Mixing available on the dedicated 3RS website (http://env.threerunwaysystem.com/en/ep-submissions.html)
(5)The action and limit levels for the two representative heavy metals chosen will be the same as that for the intensive DCM monitoring.
Table 4.3: The Control and Impact Stations during Flood Tide and Ebb Tide for General Water Quality Monitoring and Regular DCM Monitoring
|
Control Station |
Impact Stations |
|
Flood Tide |
|
|
C1 |
IM1, IM2, IM3, IM4, IM5, IM6, IM7, IM8, SR3 |
|
SR2^1 |
IM7, IM8, IM9, IM10, IM11, IM12, SR1A, SR3, SR4A, SR5A, SR6, SR8 |
|
Ebb Tide |
|
|
C1 |
SR4A, SR5A, SR6 |
|
C2 |
IM1, IM2, IM3, IM4, IM5, IM6, IM7, IM8, IM9, IM10, IM11, IM12, SR1A, SR2, SR3, SR7, SR8 |
^1 As per findings of Baseline Water Quality Monitoring Report, the control reference has been changed from C3 to SR2 from 1 Sep 2016 onwards.
4.2
Monitoring Equipment
Table 4.4 summarises the equipment used for monitoring of specific water quality parameters under the impact water quality monitoring programme.
Table 4.4: Water Quality Monitoring Equipment
|
Equipment |
Brand and Model |
Last Calibration Date |
|
Multifunctional Meter (measurement of DO, pH, temperature, salinity and turbidity) |
YSI ProDSS (serial no. 15M101244) |
16 Jun 2017 |
|
YSI ProDSS (serial no. 16J101716) |
16 Jun 2017 |
|
|
YSI 6920 V2 (serial no. 00019CB2) |
16 Jun 2017 |
|
|
YSI 6920 V2 (serial no. 000109DF) |
16 Jun 2017 |
|
|
Digital Titrator (measurement of total alkalinity) |
Titrette Digital Burette 50ml Class A (serial no.10N65665) |
19 Jun 2017 |
Other equipment used as part of the impact water quality monitoring programme are listed in Table 4.5.
Table 4.5: Other Monitoring Equipment
|
Equipment |
Brand and Model |
|
Water Sampler |
Van Dorn Water Sampler |
|
Positioning Device (measurement of GPS) |
Garmin eTrex Vista HCx |
|
Current Meter (measurement of current speed and direction, and water depth) |
Sontek HydroSurveyor |
4.3
Monitoring
Methodology
4.3.1
Measuring Procedure
Water quality monitoring samples were taken at three depths (at 1m below surface, at mid-depth, and at 1m above bottom) for locations with water depth >6m. For locations with water depth between 3m and 6m, water samples were taken at two depths (surface and bottom). For locations with water depth <3m, only the mid-depth was taken. Duplicate water samples were taken and analysed.
The water samples for all monitoring parameters were collected, stored, preserved and analysed according to the Standard Methods, APHA 22nd ed. and/or other methods as agreed by the EPD. In-situ measurements at monitoring locations including temperature, pH, DO, turbidity, salinity and water depth were collected by equipment listed in Table 4.4 and Table 4.5. Water samples for heavy metals and SS analysis were stored in high density polythene bottles with no preservative added, packed in ice (cooled to 4 ºC without being frozen), delivered to the laboratory within 24 hours of collection.
4.3.2
Maintenance and Calibration
Calibration of In-situ Instruments
Wet bulb calibration for a DO meter was carried out before commencement of monitoring and after completion of all measurements each day. Calibration was not conducted at each monitoring location as daily calibration is adequate for the type of DO meter employed. A zero check in distilled water was performed with the turbidity probe at least once per monitoring day. The probe was then calibrated with a solution of known NTU. In addition, the turbidity probe was calibrated at least twice per month to establish the relationship between turbidity readings (in NTU) and levels of suspended solids (in mg/L). Accuracy check of the digital titrator was performed at least once per monitoring day.
Calibration certificates of the monitoring equipment used in the monitoring period provided in Appendix D of the Construction Phase Monthly EM&A Report No.17 are still valid. Any updates of calibration certificates will be reported in the Monthly EM&A report if necessary.
4.3.3 Laboratory Measurement /
Analysis
Analysis of SS and heavy metals have been carried out by a HOKLAS accredited laboratory, ALS Technichem (HK) Pty Ltd (Reg. No. HOKLAS 066). Sufficient water samples were collected at all the monitoring stations for carrying out the laboratory SS and heavy metals determination. The SS and heavy metals determination works were started within 24 hours after collection of the water samples. The analysis of SS and heavy metals have followed the standard methods summarised in Table 4.6. The QA/QC procedures for laboratory measurement/ analysis of SS and heavy metals were presented in Appendix F of the Construction Phase Monthly EM&A Report No.8.
Table 4.6: Laboratory Measurement/ Analysis of SS and Heavy Metals
|
Parameters |
Instrumentation |
Analytical Method |
Reporting Limit |
|
Suspended Solid (SS) |
Analytical Balance |
APHA 2540D |
2 mg/L |
|
Heavy Metals |
|
|
|
|
Chromium (Cr) |
ICP-MS |
USEPA 6020A |
0.2 µg/L |
|
Nickel (Ni) |
ICP-MS |
USEPA 6020A |
0.2 µg/L |
4.4
Analysis and Interpretation of Monitoring Results
4.4.1 Summary of Monitoring
Results
The water quality monitoring results for turbidity, total alkalinity, and chromium obtained during the reporting period did not trigger their corresponding Action and Limit Levels stipulated in the EM&A programme for triggering the relevant investigation and follow-up procedures under the programme if being exceeded. For DO, SS, and nickel, some of the testing results exceeded the relevant Action or Limit Levels, and the corresponding investigations were conducted accordingly. Details of the exceedances are presented in Section 4.5.2.
4.4.2 Summary of Findings for
Investigation of Exceedances
During the reporting period, water quality monitoring was conducted at 12 impact (IM) stations, seven sensitive receiver (SR) stations, and three control stations in accordance with the Manual. The purpose of water quality monitoring at the IM stations is to promptly capture any potential water quality impact from the Project before it could become apparent at sensitive receivers (represented by the SR stations).
During the monitoring period, testing results exceeding the corresponding Action or Limit Levels were recorded on five monitoring days. Details of the exceedance cases are presented below.
Findings for DO Exceedances (Mid-Ebb Tide)
Table 4.7 and Table 4.8 presents a summary of the DO compliance status at IM and SR stations during mid-ebb tide for the reporting month.
Table 4.7: Summary of DO (Surface and Middle) Compliance Status (Mid-Ebb Tide)
|
IM1 |
IM2 |
IM3 |
IM4 |
IM5 |
IM6 |
IM7 |
IM8 |
IM9 |
IM10 |
IM11 |
IM12 |
SR2 |
SR3 |
SR4A |
SR5A |
SR6 |
SR7 |
|
|
01/07/2017 |
|
|
|
|
|
|
|
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|
04/07/2017 |
|
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06/07/2017 |
|
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|
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|
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|
08/07/2017 |
|
|
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|
|
|
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|
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|
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|
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|
11/07/2017 |
|
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13/07/2017 |
|
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15/07/2017 |
|
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18/07/2017 |
|
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20/07/2017 |
|
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22/07/2017 |
|
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25/07/2017 |
|
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27/07/2017 |
|
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29/07/2017 |
|
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
No. of Exceedance |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
|
Note: Detailed results are presented in Appendix D. |
||||||||||||||||||
|
|
No exceedance of Action and Limit Level |
|||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located downstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located upstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Exceedance of Limit Level recorded at monitoring station located downstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Exceedance of Limit Level recorded at monitoring station located upstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Upstream station with respect to the Project during the respective tide based on dominant tidal flow |
|||||||||||||||||
Table 4.8: Summary of DO (Bottom) Compliance Status (Mid-Ebb Tide)
|
IM1 |
IM2 |
IM3 |
IM4 |
IM5 |
IM6 |
IM7 |
IM8 |
IM9 |
IM10 |
IM11 |
IM12 |
SR2 |
SR3 |
SR4A |
SR5A |
SR6 |
SR7 |
|
|
01/07/2017 |
|
|
|
|
|
|
|
|
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|
|
|
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|
04/07/2017 |
|
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|
06/07/2017 |
|
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|
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|
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|
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|
08/07/2017 |
|
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|
11/07/2017 |
|
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13/07/2017 |
|
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15/07/2017 |
|
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18/07/2017 |
|
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20/07/2017 |
|
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22/07/2017 |
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25/07/2017 |
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27/07/2017 |
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29/07/2017 |
|
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|
|
|
|
No. of Exceedance |
1 |
1 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
|
Note: Detailed results are presented in Appendix D. |
||||||||||||||||||
|
Legend: |
||||||||||||||||||
|
|
No exceedance of Action and Limit Level |
|||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located downstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located upstream of the Project based on dominant tidal flow |
|||||||||||||||||
|
|
Upstream station with respect to the Project during the respective tide based on dominant tidal flow |
|||||||||||||||||
Exceedances of Action or Limit Levels were recorded on one monitoring day. Repeat in-situ measurements were conducted on 7 July 2017 as stipulated in the Manual. No exceedance was recorded during the repeat measurement. As some of the exceedances occurred at stations located downstream of the Project, which might be affected by Project’s construction activities, exceedance investigation was carried out.
As part of the investigation on downstream exceedance events, details of the Project’s marine construction activities on the concerned monitoring day was collected, as well as any observations during the monitoring. The findings are summarized in Table 4.9.
Table 4.9: Summary of Findings from Investigations of DO Exceedances
|
Date |
Marine construction works nearby |
Approximate distance from marine construction works*
|
Status of water quality measures (if applicable) |
Construction vessels in the vicinity |
Turbidity / Silt plume observed near the monitoring station |
Exceedance due to Project |
|
06/07/2017 |
DCM works Sand blanket laying |
Around 500m |
Silt curtain deployed |
No |
No |
No |
|
* This refers to the approximate distance between the marine construction works and the nearest monitoring stations with exceedance. |
||||||
According to the investigation findings, it was confirmed that both DCM and sand blanket laying activities were operating normally with silt curtains deployed as additional measures. The silt curtains were maintained properly.
For the exceedance events at downstream monitoring stations, namely IM1, IM2, and SR4A, it is noted that exceedances also occurred at upstream stations on the same day, and no exceedance was recorded at other downstream IM stations, including IM3, which was located closer to active construction activities. Besides, lower DO concentrations were recorded during baseline monitoring at these monitoring stations. Based on these findings, the exceedances were possibly due to natural fluctuation in the vicinity of these monitoring stations, and considered not due to the Project.
Findings for DO Exceedances (Mid-Flood Tide)
Table 4.10 and Table 4.11 presents a summary of the DO compliance status at IM and SR stations during mid-flood tide for the reporting month.
Table 4.10: Summary of DO (Surface and Middle) Compliance Status (Mid-Flood Tide)
|
IM1 |
IM2 |
IM3 |
IM4 |
IM5 |
IM6 |
IM7 |
IM8 |
IM9 |
IM10 |
IM11 |
IM12 |
SR3 |
SR4A |
SR5A |
SR6 |
SR7 |
|
|
04/07/2017 |
|
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|
06/07/2017 |
|
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|
08/07/2017 |
|
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11/07/2017 |
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13/07/2017 |
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15/07/2017 |
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18/07/2017 |
|
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20/07/2017 |
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22/07/2017 |
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25/07/2017 |
|
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|
27/07/2017 |
|
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|
29/07/2017 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
No. of Exceedance |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
|
Note: Detailed results are presented in Appendix D. |
|||||||||||||||||
|
Legend: |
|||||||||||||||||
|
|
No exceedance of Action and Limit Level |
||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located downstream of the Project based on dominant tidal flow |
||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located upstream of the Project based on dominant tidal flow |
||||||||||||||||
|
|
Upstream station with respect to the Project during the respective tide based on dominant tidal flow |
||||||||||||||||
Table 4.11: Summary of DO (Bottom) Compliance Status (Mid-Flood Tide)
|
IM1 |
IM2 |
IM3 |
IM4 |
IM5 |
IM6 |
IM7 |
IM8 |
IM9 |
IM10 |
IM11 |
IM12 |
SR3 |
SR4A |
SR5A |
SR6 |
SR7 |
|
|
04/07/2017 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
06/07/2017 |
|
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|
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|
08/07/2017 |
|
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|
|
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|
11/07/2017 |
|
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|
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|
13/07/2017 |
|
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|
15/07/2017 |
|
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18/07/2017 |
|
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20/07/2017 |
|
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22/07/2017 |
|
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|
25/07/2017 |
|
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|
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|
27/07/2017 |
|
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|
|
|
|
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|
|
|
|
29/07/2017 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
No. of Exceedance |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
Note: Detailed results are presented in Appendix D. |
|||||||||||||||||
|
Legend: |
|||||||||||||||||
|
|
No exceedance of Action and Limit Level |
||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located downstream of the Project based on dominant tidal flow |
||||||||||||||||
|
|
Exceedance of Action Level recorded at monitoring station located upstream of the Project based on dominant tidal flow |
||||||||||||||||
|
|
Upstream station with respect to the Project during the respective tide based on dominant tidal flow |
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Exceedances of Action Levels were recorded on one monitoring day. Repeat in-situ measurements were conducted on 7 July 2017 as stipulated in the Manual. No exceedance was recorded during the repeat measurement. As there was exceedance occurred at a station located upstream of the Project, which would unlikely be affected by Project’s construction activities, exceedance investigation focused on downstream exceedance events was carried out.
As part of the investigation on downstream exceedance events, details of the Project’s marine construction activities on concerned monitoring day were collected, as well as any observations during the monitoring. The findings are summarized in Table 4.9.
According to the investigation findings, it was confirmed that both DCM and sand blanket laying activities were operating normally with silt curtains deployed as additional measures. The silt curtains were maintained properly.
For the exceedance events at downstream monitoring stations, namely IM8, IM9, and SR3, it is noted that the DO concentration at surface and middle level at C1, the corresponding control station for IM8 and SR3, was also below Action Level during the same tide. Besides, no exceedance was recorded at other downstream monitoring stations, including IM7 and IM10, which were similarly close to active construction activities. Based on these findings, the exceedances were possibly due to natural fluctuation in the vicinity of these monitoring stations, and considered not due to the Project.
Findings for SS Exceedances (Mid-Ebb Tide)
Table 4.12 presents a summary of the SS compliance status at IM and SR stations during mid-ebb tide for the reporting month.
Table 4.12: Summary of SS Compliance Status (Mid-Ebb Tide)
|
IM1 |
IM2 |
IM3 |
IM4 |
IM5 |
IM6 |
IM7 |
IM8 |
IM9 |
IM10 |
IM11 |
IM12 |
SR2 |
SR3 |
SR4A |
SR5A |
SR6 |
SR7 |
SR8 |
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01/07/2017 |
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04/07/2017 |
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06/07/2017 |
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08/07/2017 |
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11/07/2017 |
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13/07/2017 |
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15/07/2017 |
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18/07/2017 |
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20/07/2017 |
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