Expansion of Hong Kong International Airport into a Three-Runway System

Construction Phase Monthly EM&A Report No.20 (For August 2017)

September 2017

 

 

  

 

Contents

Executive Summary

1      Introduction

1.1    Background

1.2    Scope of this Report

1.3    Project Organisation

1.4    Summary of Construction Works

1.5    Summary of EM&A Programme Requirements

2      Air Quality Monitoring

2.1    Monitoring Stations

2.2    Monitoring Requirements and Schedule

2.3    Monitoring Equipment

2.4    Monitoring Methodology

2.4.1     Measuring Procedure

2.4.2     Maintenance and Calibration

2.5    Analysis and Interpretation of Monitoring Results

3      Noise Monitoring 

3.1    Monitoring Stations

3.2    Monitoring Requirements and Schedule

3.3    Monitoring Equipment 

3.4    Monitoring Methodology

3.4.1     Monitoring Procedure

3.4.2     Maintenance and Calibration 

3.5    Analysis and Interpretation of Monitoring Results

4      Water Quality Monitoring

4.1    Monitoring Stations 

4.2    Monitoring Requirements and Schedule

4.2.1     Action and Limit Levels for Water Quality Monitoring

4.3    Monitoring Equipment

4.4    Monitoring Methodology

4.4.1     Measuring Procedure 

4.4.2     Maintenance and Calibration

4.4.3     Laboratory Measurement / Analysis

4.5    Analysis and Interpretation of Monitoring Results

4.5.1     Summary of Monitoring Results

4.5.2     Summary of Findings for Investigation of Exceedances

5      Waste Management

5.1    Monitoring Requirements

5.2    Waste Management Status 

6      Chinese White Dolphin Monitoring

6.1    CWD Monitoring Requirements

6.2    CWD Monitoring Transects and Stations

6.2.1     Small Vessel Line-transect Survey

6.2.2     Land-based Theodolite Tracking

6.3    CWD Monitoring Methodology

6.3.1     Small Vessel Line-transect Survey

6.3.2     Photo Identification

6.3.3     Land-based Theodolite Tracking

6.4    Monitoring Results and Observations

6.4.1     Small Vessel Line-transect Survey

6.4.2     Photo Identification 

6.4.3     Land-based Theodolite Tracking

6.5    Progress Update on Passive Acoustic Monitoring

6.6    Site Audit for CWD-related Mitigation Measures

6.7    Timing of Reporting CWD Monitoring Results

6.8    Summary of CWD Monitoring

7      Environmental Site Inspection and Audit

7.1    Environmental Site Inspection

7.2    Audit of Route Diversion and Speed Control of the SkyPier High Speed Ferries

7.3    Audit of Construction and Associated Vessels

7.4    Implementation of Dolphin Exclusion Zone 

7.5    Ecological Monitoring

7.6    Status of Submissions under Environmental Permits

7.7    Compliance with Other Statutory Environmental Requirements

7.8    Analysis and Interpretation of Complaints, Notification of Summons and Status of Prosecutions 

7.8.1     Complaints

7.8.2     Notifications of Summons or Status of Prosecution 

7.8.3     Cumulative Statistics

8      Future Key Issues and Other EIA & EM&A Issues

8.1    Construction Programme for the Coming Reporting Period

8.2    Key Environmental Issues for the Coming Reporting Period

8.3    Monitoring Schedule for the Coming Reporting Period

9      Conclusion and Recommendation 

 

 

Tables

Table 1.1: Contact Information of Key Personnel 5

Table 1.2: Summary of status for all environmental aspects under the Updated EM&A Manual 7

Table 2.1:  Locations of Impact Air Quality Monitoring Stations  9

Table 2.2:  Action and Limit Levels for 1-hour TSP  9

Table 2.3:  Air Quality Monitoring Equipment 9

Table 2.4: Summary of 1-hour TSP Monitoring Results  10

Table 3.1: Locations of Impact Noise Monitoring Stations  11

Table 3.2: Action and Limit Levels for Construction Noise  11

Table 3.3: Noise Monitoring Equipment 12

Table 3.4: Summary of Construction Noise Monitoring Results  13

Table 4.1: Monitoring Locations and Parameters for Impact Water Quality Monitoring  14

Table 4.2: Action and Limit Levels for General Water Quality Monitoring and Regular DCM Monitoring  15

Table 4.3: The Control and Impact Stations during Flood Tide and Ebb Tide for General Water Quality Monitoring and Regular DCM Monitoring  16

Table 4.4: Water Quality Monitoring Equipment 16

Table 4.5: Other Monitoring Equipment 16

Table 4.6: Laboratory Measurement/ Analysis of SS and Heavy Metals  18

Table 4.7: Summary of DO (Surface and Middle) Compliance Status (Mid-Ebb Tide) 18

Table 4.8: Summary of DO (Bottom) Compliance Status (Mid-Ebb Tide) 19

Table 4.9: Summary of Findings from Investigations of DO Exceedances  20

Table 4.10: Summary of Turbidity Compliance Status (Mid-Ebb Tide) 21

Table 4.11: Summary of Findings from Investigations of Turbidity Exceedances  21

Table 4.12: Summary of Turbidity Compliance Status (Mid-Flood Tide) 22

Table 4.13: Summary of Findings from Investigations of Turbidity Exceedances  23

Table 4.14: Summary of SS Compliance Status (Mid-Ebb Tide) 23

Table 4.15: Summary of SS Compliance Status (Mid-Flood Tide) 24

Table 4.16: Summary of Findings from Investigations of SS Exceedances  25

Table 4.17: Summary of Nickel Compliance Status (Mid-Ebb Tide) 26

Table 4.18: Summary of Nickel Compliance Status (Mid-Flood Tide) 27

Table 4.19: Summary of Findings from Investigations of Nickel Exceedances  28

Table 5.1: Action and Limit Levels for Construction Waste  30

Table 6.1: Derived Values of Action Level (AL) and Limit Level (LL) for Chinese White Dolphin Monitoring  31

Table 6.2: Coordinates of Transect Lines in NEL, NWL, AW, WL and SWL Survey Areas  32

Table 6.3: Land-based Survey Station Details  33

Table 6.4: Comparison of CWD Encounter Rates of the Whole Survey Area with Action Levels  37

Table 6.5: Summary of Photo Identification  38

Table 6.6: Summary of Survey Effort and CWD Group of Land-based Theodolite Tracking  38

Table 7.1: Summary of Key Audit Findings against the SkyPier Plan  42

Table 7.2: Status of Submissions under Environmental Permit 44

 

 

 

 

 

 

 

 

 

Figures

Figure 1.1- 1.2

Key Construction Areas in this Reporting Period

Figure 2.1

Locations of Air and Noise Monitoring Stations and Chek Lap Kok Wind Station

Figure 3.1

Water Quality Monitoring Stations

Figure 6.1

Vessel based Dolphin Monitoring Transects in Construction, Post-construction and Operation Phases

Figure 6.2

Land based Dolphin Monitoring in Baseline and Construction Phases

Figure 6.3

Sightings Distribution of Chinese White Dolphins

Figure 6.4

Plots of First Sightings of All CWD Groups obtained from Land-based Stations

Figure 6.5

Location for Autonomous Passive Acoustic Monitoring

Figure 7.1

Duration of the SkyPier HSFs travelled through the SCZ for 1 – 31 August 2017

 

Appendices

 

 

Appendix A

Contract Description

Appendix B

Environmental Mitigation Implementation Schedule (EMIS) for Construction Phase

Appendix C

Monitoring Schedule

Appendix D

Monitoring Results

Appendix E

Calibration Certificates

Appendix F

Status of Environmental Permits and Licences

Appendix G

Cumulative Statistics on Exceedances, Environmental Complaints, Notification of Summons and Status of Prosecutions

Appendix H

Data of SkyPier HSF Movements to/from Zhuhai and Macau (between 1 and 31 August 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 20th 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 August 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, laying of sand blanket, site office establishment, horizontal directional drilling (HDD) works, concrete removal works, piling and excavation 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 36 sets of construction dust measurements, 25 sets of construction noise measurements, 14 events of water quality measurements, 1 round of terrestrial ecology monitoring on Sheung Sha Chau Island, 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.

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 16 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 was one record of dolphin sighting within the DEZ of DCM works in this reporting period. 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 August 2017 were in the range of 11 to 91 daily movements, which are within the maximum daily cap of 125 daily movements. A total of 744 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 (9.7 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, terrestrial ecology, 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 period. 

The water quality monitoring results for 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, turbidity, 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.

The monthly terrestrial ecology monitoring on Sheung Sha Chau observed that HDD works were conducted at the daylighting location and there was no encroachment upon the egretry area nor any significant disturbance to the egrets foraging at Sheung Sha Chau by the works.

Summary of Upcoming Key Issues

Key activities anticipated in the next reporting period of the Project include the following:

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 geotextile; and

    DCM works.

 

Reclamation Works:

Contract 3206 Main Reclamation Works

    Laying of sand blanket.

 

Airfield Works:

Contract 3301 North Runway Crossover Taxiway

    CLP cable ducting work.

 

Terminal 2 Expansion Works:

Contract 3501 Antenna Farm and Sewage Pumping Station

    Excavation and piling works.

 

Contract 3502 Terminal 2 Automated People Mover (APM) Depot Modification Works

    Removal of existing concrete.

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.

DEZ Monitoring for DCM Works by Contractor

Chemical Spill Drill conducted by the Contractor

Dolphin Observer 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

 

A complaint on sand filling materials was received on 8 Aug 2017.

Investigation details of the complaint is presented in S7.8.1.

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

Remark: ^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 20th 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 August 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 period. 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

Roy Man

3922 9376

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 Liu

 

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

 

David Hung

 

9765 6151

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

 

 

Environmental Officer

Kelvin Cheung

9305 6081

Contract 3502 Terminal 2 APM Depot Modification Works

(Build King Construction Ltd.)

Project Manager

Kivin Cheng

9380 3635

 

Environmental Officer

Chun Pong Chan

9187 7118

 

1.4         Summary of Construction Works

The key activities of the Project carried out in the reporting period included DCM works, laying of sand blanket, site office establishment, HDD works, concrete removal works, piling and excavation 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

The ecological monitoring was resumed since August 2017.

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 period, impact monitoring of air quality, noise, water quality, waste management, ecology, landscape & visual and CWD were carried out in the reporting period.

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-001 (Serial No. 934393)

26 Oct 2016

 

SIBATA LD-3B-002 (Serial No. 974350)

26 Oct 2016

 

SIBATA LD-3B-003 (Serial No. 276018)

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. The calibration certificates for portable direct reading dust meter are updated and provided in Appendix E.

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

8 – 28

306

500

AR2

22 – 46

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, Appendix D of the Construction Phase Monthly EM&A Report No. 17, and Appendix E of the Construction Phase Monthly EM&A Report No. 19 are still valid.

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)

70 – 72

75

NM3A

61 – 63

75

NM4(i)

60 – 65

70(ii)

NM5(i)

53 – 61

75

NM6(i)

68 – 73

75

Notes:    (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 noise at NM1A, helicopter and aircraft noise at NM3A, helicopter noise and construction noise from nearby school at NM4, aircraft, helicopter, and dog barking noise at NM5, and insect, aircraft, helicopter, and marine vessel noise at NM6 in this reporting period. 

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

Description

Coordinates

Parameters

Station

 

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 rough, 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. The flood tide monitoring session on 22 August 2017 was cancelled due to hoisting Strong Wind Signal No. 3 and adverse sea condition.

4.2.1       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.

4.3         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

4.4         Monitoring Methodology

4.4.1      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.

4.4.2      Maintenance and Calibration

Calibration of In-situ Instruments

All in-situ monitoring instrument were checked, calibrated and certified by a laboratory accredited under HOKLAS before use. Responses of sensors and electrodes were checked with certified standard solutions before each use.

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.18 are still valid. Any updates of calibration certificates will be reported in the Monthly EM&A report if necessary.

4.4.3      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

4.5         Analysis and Interpretation of Monitoring Results

4.5.1      Summary of Monitoring Results 

The water quality monitoring results for 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, turbidity, SS, and nickel, some of the testing results exceeded the relevant Action or Limit Levels, and the corresponding investigations were conducted accordingly. It should be noted that two typhoons, namely Typhoon Hato and Typhoon Pakhar hit Hong Kong during August 2017. The water quality monitoring results might be affected by these typhoons. Detailed analysis of the exceedances are presented in Section 4.5.2.

4.5.2      Summary of Findings for Investigation of Exceedances

During the reporting period, water quality monitoring was conducted at 12 IM stations, 7 SR stations, and 3 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 period.

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

01/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

03/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

05/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

08/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

12/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

17/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

19/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

22/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

24/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

26/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

29/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No. of Exceedance

2

0

0

0

0

1

1

1

1

0

0

0

0

1

2

0

0

1

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

 

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

01/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

03/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

05/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

08/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

12/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

17/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

19/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

22/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

24/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

26/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

29/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No. of Exceedance

1

0

0

0

0

0

1

1

1

0

0

0

0

1

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 5 and 22 August 2017. Repeat in-situ measurement was conducted on 6 August 2017 as stipulated in the Manual and no exceedance was recorded during the repeat measurement. However, as Hurricane Signal No. 10 was hoisted on 23 August 2017, the repeat in-situ measurement on 23 August 2017 was cancelled. Regular monitoring at all stations resumed on 24 August 2017. 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

05/08/2017

DCM works

Sand blanket laying

Around 500m

Silt curtain deployed

No

No

No

22/08/2017

DCM works

Sand blanket laying

Around 800m

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, SR4A and SR7 on 5 August 2017, it is noted that DO concentration at surface and middle level at the corresponding control station C2 was also lower than the Limit Level during the same tide. Exceedances also occurred at upstream stations on the same day. 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.

Stand By Signal No. 1 was hoisted when exceedances were recorded at IM1 and SR4A on 22 August 2017. Lower DO concentrations were recorded during baseline monitoring at these monitoring stations. Besides, no exceedance was recorded at other downstream monitoring stations, including IM2, which was located closer to active construction works than IM1 and SR4A. 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 Turbidity Exceedances (Mid-Ebb Tide)

Table 4.10 presents a summary of the turbidity compliance status at IM and SR stations during mid-ebb tide for the reporting period.

Table 4.10: Summary of Turbidity Compliance Status (Mid-Ebb Tide)

IM1

IM2

IM3

IM4

IM5

IM6

IM7

IM8

IM9

IM10

IM11

IM12

SR2

SR3

SR4A

SR5A

SR6

SR7

01/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

03/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

05/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

08/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

12/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

17/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

19/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

22/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

24/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

26/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

29/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No. of Exceedance

0

0

0

1

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 Level were recorded on one monitoring day. Stand By Signal No. 1 was hoisted when the exceedances were recorded. Due to hoisting Gale or Storm Signal No.8 SE, the repeat measurement on 27 August 2017 was rescheduled to 28 August 2017. No exceedance was recorded during the repeat measurement. As one of the exceedances occurred at a station located upstream of the Project, which would unlikely be affected by Project’s construction activities, exceedance investigation focusing 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 4.11.

Table 4.11: Summary of Findings from Investigations of Turbidity 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

26/08/2017

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 IM4 and SR4A, it is noted from Table 4.10 that the exceedances appeared to be isolated cases with no temporal trend and no clear spatial trend to indicate turbidity rising due to Project activities. The investigation results shown in Table 4.11 also showed that no construction vessel, nor silt plume was observed in the vicinity of IM4 and SR4A on 26 August 2017. It is also noted that no exceedance was recorded at monitoring station IM3, which is located similarly downstream and close to active construction works on 26 August 2017 during ebb tide, while no exceedances were identified in the repeat turbidity measurements. Based on the above, the exceedances were considered not due to the Project, and were possibly due to natural fluctuation in vicinity of IM4 and SR4A.

Findings for Turbidity Exceedances (Mid-Flood Tide)

Table 4.12 presents a summary of the turbidity compliance status at IM stations during mid-flood tide for the reporting period.

Table 4.12: Summary of Turbidity Compliance Status (Mid-Flood Tide)

IM1

IM2

IM3

IM4

IM5

IM6

IM7

IM8

IM9

IM10

IM11

IM12

SR3

SR4A

SR5A

SR6

SR7

01/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

03/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

05/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

08/08/2017

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10/08/2017