CONTENTS

 

 

 

Appendix A        Master Programme

 

Appendix B        Overview of Desalination Plant in Tseung Kwan O

 

Appendix C        Summary of Implementation Status of Environmental Mitigation

 

Appendix D       Water Quality Monitoring Graphical Presentation

Appendix E        Summary of Exceedances

Appendix F        Waste Flow Table

Appendix G        Complaint Log

Appendix H       Event/Action Plan for Water Quality Monitoring

 Appendix I        Event/Action Plan for Construction Noise Exceedance

 

 

 

 

 


EXECUTIVE SUMMARY

 

INTRODUCTION

 

A1. The Project, Design, Build and Operate First Stage of Tseung Kwan O Desalination Plant (TKODP), is a Designated Project under the Environmental Impact Assessment Ordinance (Cap. 499) (EIAO) and is currently governed by a Further Environmental Permit (EP No. FEP- 01/503/2015/A) for the construction and operation of the Contract.

 

A2. In accordance with the Environmental Monitoring and Audit (EM&A) Manual for the Contract, EM&A works for marine water quality, noise, waste management and ecology should be carried out by Environmental Team (ET), Acuity Sustainability Consulting Limited (ASCL), during the construction phase of the Contract.

 

A3.  This is the 8th Quarterly EM&A Report, prepared by ASCL, for the Contract summarizing the monitoring results and audit findings of the EM&A programme at and around Tseung Kwan O Area 137 (TKO 137) during the reporting period from 1 December 2021 to 28 February 2022.

 

A4. The EM&A programme for this contract has covered environmental monitoring on construction noise level at selected NSRs and Contractor’s environmental performance auditing in the aspects of construction dust, construction noise, water quality, waste management, Landscape and Visual and Ecology.

 

SUMMARY OF MAIN WORKS UNDERTAKEN & KEY MITIGATION MEASURES IMPLEMENTED

 

A5.        Key activities carried out in this reporting period for the Project included the followings:

-              Land Survey;

-              Construction of ActiDAFF Roof Slab;

-              Construction of Reverse Osmosis (RO) Building - staircases; water tank; Electrical Building roof and internal finishing works;

-              Construction of Product Water Storage Tank (PWST) perimeter wall and Electrical Building’s roof slab;

-              Construction of sludge thickener, Post Treatment Building (PTB);

-              Construction of On-Site Chlorine Generation Building (OSCG Bldg);

-              Manhole construction and Glass Reinforced Plastic (GRP) pipe installation;

-              Commence construction of manholes no. 8 and no. 9 adjacent to PWST;

-              Construction of manholes no.15 and no.16 adjacent to ActiDAFF and RO;

-              Construction of 1/F to 2/F walls and columns of Administration Building

-              Construction of Post Treatment Building 1/F;

-              Construction of first floor columns and walls of Administration Building;

-              Construction of structural wall and Roof of Chemical Building;

-              Construction of reinforced concrete (R.C) footing and support of Inspection Corridor;

-              Internal finishing work in Product Water Storage Tank (PWST), Main Electrical & Central Chiller Plant Building;

-              Outfall Shaft dewatering; rock cutting and excavation works;

-              Outfall Shaft - works inside the caisson to check and grout/welding water leaking spots;

-              Outfall Shaft - welding works of working platform atop the caisson;

-              Outfall Shaft - material lifting for rock coring and pumping clean seepage water within silt curtain area;

-              Intake tunnel - Demobilize the pipe jacking system and commencement of grouting works;

-              Excavation & Lateral Support (ELS) erection and marine dredging commencement and disposal at Intake Shaft;

-              Installation of brackets and welding works of the waling at Intake Shaft;

-              Pipe jacking at Combined Shaft for Intake & Outfall pipelines;

-              Cable drawpit construction;

-              Glass Reinforced Plastic (GRP) pipe lamination and laying;

-              Construction of 1st floor structural wall of Chemical Building;

-              Wan Po Road Sewage Rising Main Works - Temporary Traffic Arrangement (TTA), excavation and laying High-Density Polyethylene (HDPE) pipe;

-              Construction of On-Site Chlorine Generation (OSCG) Building footing and roof floor;

-              Construction of base slab of Pump house;

-              Dismantling of tower crane TC03;

-              Construction of carbon dioxide (CO2) tank footing

-              E&M works - ActiDAFF - scaffolding, installation of E&M piping; and

-              E&M works - Reverse Osmosis (RO) Building - Fire services installation;

 

A6.   The major environmental impacts brought by the above construction works include:

-      Construction dust and noise generation from marine construction works, excavation works, ELS installation works, breaking of concrete surface and construction works; rock cutting works and pipe piling driving works

-      Waste generation from the construction activities

-      Impact on water quality from marine construction works and inland construction works

 


A7.        The key environmental mitigation measures implemented for the Project in this reporting period associated with the above construction works include:

-      Dust suppression by regular wetting and water spraying for construction works

-      Reduction of noise from equipment and machinery on-site and regularly inspection to machinery and plants/vehicles on-site to ensure proper functioning

-      Sorting and storage of general refuse and construction waste

-      Deployment of temporary silt curtain in the area where marine construction works were conducted and deployment of water sedimentation tanks for treatment of wastewater at inland areas before discharge

SUMMARY OF EXCEEDANCE & INVESTIGATION & FOLLOW-UP

 

A8. No noise monitoring was conducted during the reporting period since there are no project- related construction activities undertaken within a radius of 300m from the monitoring locations. No exceedance of the Action Level was recorded during the reporting period.

 

A9. The EM&A works for water quality were conducted during the reporting period in accordance with the EM&A Manual.

 

A10. Water quality monitoring was conducted as schedule in the reporting period. One hundred and ninety-three (193) action level exceedances and One hundred and thirty-two (132) limit level exceedances for suspended solids (SS) of impact water quality monitoring were recorded.

 

A11. In this reporting period, 66 times of landfill gas monitoring were recorded at Wan Po Road (Ch1+360 - Ch1+513). No action and limit level exceedance for methane, oxygen and carbon dioxide was recorded. Monitoring was conducted during excavations at 1m depth or more within the consultation zone and whenever workers entered the excavation on the day.

 

A12. Weekly site inspections of the construction works were also carried out by ET to audit the mitigation measures implementation status. 13 times of weekly Joint site inspections were carried out by ET and IEC.

 

A13.  A summary of the EM&A activities in this reporting period is listed in Table I and summary of the environmental exceedance of the reporting period is tabulated in Table II.

 

 

 


Table I                 Summary Table for EM&A Activities in the Reporting Period

EM&A Activities

December 2021

January 2022

February 2022

Noise Monitoring

N/A

N/A

N/A

Water               Quality Monitoring

2, 4, 7, 9, 11, 14, 16, 18,

21, 23, 25, 28 and 30

Dec 2021

1, 4, 6, 8, 11, 13, 15,

18 ,20, 22, 25, 27, 29

and 31 Jan2022

4, 8, 10, 12, 15, 17, 19,

22, 24 and 26 Feb 2022.

Landfill                    Gas monitoring

31 Dec 2021

1, 4, 5, 6, 7, 8, 10, 11, 12,

13, 14, 15, 17, 18, 19,

20, 21, 22, 24, 25, 26,

27, 28, 29 and 31 Jan

2022

8, 9, 10, 11, 12, 14, 15,

16 and 17 Feb 2022

Environmental Site Inspection

7, 15, 22 and 31 Dec

2021

4, 11, 18, 26 and 31 Jan

2022

8, 17, 23 and 28 Feb

2022

 

Table II               Summary Table for Exceedance in the Reporting Period

Environmental Monitoring

Parameter

No of non- Project related

exceedance

Total No. of non-Project related

exceedance

No of Project related

exceedance

Total No. of Project related

exceedance

AL

LL

AL

LL

Noise

Leq (30min)

N/A

N/A

N/A

N/A

N/A

N/A

 

Water

DO

0

0

0

0

0

0

Turbidity

0

0

0

0

0

0

SS

193

132

325

0

0

0

pH

0

0

0

0

0

0

Salinity

0

0

0

0

0

0

 

Landfill Gas

O2

0

0

0

0

0

0

CH4

0

0

0

0

0

0

CO2

0

0

0

0

0

0

 

COMPLAINT HANDLING AND PROSECUTION

 

A14.     No environmental complaint was received during the reporting period.

 

A15.     Neither notifications of summons nor prosecution was received for the Project.

 

REPORTING CHANGE

 

A16.     There was no change to be reported that may affect the on-going EM&A programme.

 

 

 

 

 


1.              BASIC PROJECT INFORMATION

 

1.1.      BACKGROUND

The Acciona Agua, S.A. Trading, Jardine Engineering Corporation Limited and China State Construction Engineering (Hong Kong) Limited and as AJC Joint Venture (AJCJV) is contracted to carry out the Design, Build and Operate First Stage of Tseung Kwan O Desalination Plant (DPTKO) under Contract No. 13/WSD/17 (the Contract).

Acuity Sustainability Consulting Limited (ASCL) is commissioned by AJCJV to undertake the Environmental Team (ET) services as required and/or implied, both explicitly and implicitly, in the Environmental Permit (EP), Environmental Impact Assessment Report (EIA Report) (Register No. AEIAR-192/2015) and Environmental Monitoring and Audit Manual (EM&A Manual) for the Contract; and to carry out the Environmental Monitoring and Audit (EM&A) programme in fulfillment of the EIA Report’s EM&A requirements and Contract No. 13/WSD/17 Specification requirements.

Pursuant to the Environmental Impact Assessment Ordinance (EIAO), the Director of Environmental Protection granted the Environmental Permit (No. EP-01/503/2015) and Variation of Environmental Permit (No. EP-01/503/2015/A) to Water Supplies Department (WSD); and granted the Further Environmental Permit (No. FEP-01/503/2015/A) to AJCJV for the Contract.

1.2.      THE REPORTING SCOPE

This is the 8th Quarterly EM&A Report for the Project which summarizes the key findings of the EM&A programme during the reporting period from 1 December 2021 to 28 February 2022.

 

1.3.      PROJECT ORGANIZATION-

The Project Organization structure for Construction Phase is presented in Figure 1.1.

 

Figure 1.1        Project Organization Chart

 


Contact details of the key personnel are presented in Table 1.1 below:

 

Table 1.1         Contact Details of Key Personnel

 

Party

Position

Name

Telephone no.

Project Proponent

SE/CM2

Benny Lam

2634-3573

Supervising Officer (Binnies Hong Kong Limited)

Project Manager

Christina Ko

2608-7302

Chief Resident Engineer

Roger Wu

6343-1002

The Jardine Engineering Corporation, Limited, China State Construction Engineering (Hong Kong) Limited and Acciona Agua, S.A. Trading

Project Manager

Stephen Yeung

2807-4665

Environmental Monitoring Manager

 

Brian Kam

 

9456-9541

Acuity Sustainability Consulting Limited

Environmental Team Leader

 

Jacky Leung

 

2698-6833

 

ANewR Consulting Limited

Independent Environmental Checker (IEC)

 

Louis Kwan

 

2618-2831

 

1.4.      SUMMARY OF CONSTRUCTION WORKS

Details of the major construction activities undertaken in this reporting period are shown as below. The construction programme is presented in Appendix A.

 

Key activities carried out in this reporting period for the Project included the following:

-      Land Survey;

-      Construction of ActiDAFF parapet and solar panel supports at roof

-      Construction of Reverse Osmosis (RO) Building - staircases and internal finishing;

-      Construction of Sludge tank, sludge thickener and Post treatment building (PTB);

-      Construction of On-Site Chlorine Generation (OSCG) Building and carbon dioxide (CO2) tank area;

-      Internal finishing works at Product Water Storage Tank (PWST) and Main Electrical & Central Chiller Plant Building

-      Construction of manhole and Glass Reinforced Plastic (GRP) pipe installation;

-      Commence construction of Manholes no.15 and no.16 adjacent to ActiDAFF and Reverse Osmosis Area (RO);

-      Construction of first and second floor walls and columns of Administration Building;

-      Construction of reinforced concrete (RC) support of Inspection Corridor;

-      Construction of floor structural wall and roof of Chemical Building;

-      Dewatering, predrill, rock cutting and excavations at Outfall Shaft;

-      Excavation & Lateral Support (ELS) erection and commencement of marine dredging and disposal at Intake Shaft;

-      Retrieval of DN 2500 Tunnel Boring Machine (TBM) underwater at Intake Shaft;

-      Demobilize the pipe jacking system and commencement of grouting works at Intake Shaft;

-      Concrete blinding laying and backfill with aggregate at Intake Shaft;

-      Pipe jacking works at Combined Shaft for Intake & Outfall pipelines;

-      Construction of base slab of Pump house

-      E&M works - ActiDAFF - scaffolding, installation of E&M piping;

-      E&M works - RO- Fire services installation;

-      E&M works - CO2 tank area - installation of Silos; and

-      E&M works - Chiller Building - installation of chillers;

 

1.5.         SUMMARY OF ENVIRONMENTAL STATUS

A summary of the valid permits, licences, and /or notifications on environmental protection for this Project is presented in Table 1.2.

Table 1.2 Summary of the Status of Valid Environmental Licence, Notification, Permit and Documentations

 

Permit/ Licenses/ Notification

Reference

Validity Period

Environmental Permit

FEP - 01/503/2015/A

Throughout the Contract

Notification of Construction Works under the Air Pollution Control (Construction

Dust) Regulation (Form NA)

Ref. No.: 451539

-

Wastewater Discharge Licence (Land and Marine works)

WT00035775-2020

24/07/2020 -31/07/2025

Chemical Waste Producer Registration

5213-839-A2987-01

Throughout the Contract

Billing Account for Disposal of Construction Waste

7036276

Throughout the Contract

Construction Noise Permit (24 hours) -

CNP for general works, TBM at Combined Shaft and marine works

GW-RE1041-21

01/11/2021 - 30/04/2022

Vessel CHITs for fill disposal

7039300

20/01/2022 - 20/04/2022

Dumping at Sea Ordinance (DASO) Permit (Category L)

EP/MD/22‐028

02/08/2021 - 01/02/2022

Dumping at Sea Ordinance (DASO) Permit (Category M)

EP/MD/22-083

03/12/2021 - 02/01/2022

 

The status for all environmental aspects is presented in Table 1.3.


Table 1.3 Summary of Status for Key Environmental Aspects under the EM&A Manual

 

Parameters

Status

Water Quality

Baseline Monitoring under EM&A Manual

The baseline water quality monitoring was conducted between 12 May 2020 and 6 June 2020

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

Waste Management

Mitigation Measures in Waste Management Plan

On-going

Landfill Gas

Regular Monitoring when Construction Works are within the 250m Consultation Zone

In this reporting period, 66 times of landfill gas monitoring were recorded at Wan Po Road (Ch1+360 - Ch1+513). No exceedance of action and limit level for methane, oxygen and carbon dioxide was observed. Monitoring was conducted during excavations at 1m depth or more within the consultation zone and whenever workers entered the

excavation on the day.

Environmental Audit

Site Inspection covering Measures of Air Quality, Noise Impact, Water

Quality, Waste, Ecological Quality, Fisheries, Landscape and Visual

On-going

 

Other than the EM&A work by ET, environmental briefings, trainings and regular environmental management meetings were conducted, in order to enhance environmental awareness and closely monitor the environmental performance of the contractors.

The EM&A programme has been implemented in accordance with the recommendations presented in the approved EIA Report and the EM&A 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 C.

 

 

 

 

 

 


2.              NOISE

 

2.1.      MONITORING REQUIREMENTS

To ensure no adverse noise impact, construction noise monitoring is recommended to be carried out within 300m radius from the nearby noise sensitive receivers (NSRs), during construction phase. The NSRs selected as monitoring station are (i) NSR4 - Creative Secondary School, (ii) NSR24 - PLK Laws Foundation College, and (iii) NSR31 - School of Continuing and Professional Studies - CUHK respectively.

No impact construction noise monitoring was conducted in the reporting period due to the overly distant monitoring station from the works location, where they were farther than 1 km from the closet monitoring station NSR4 to the works location.

2.2.      MONITORING PARAMETERS, FREQUENCY AND DURATION

Construction noise level would be measured in terms of the A-weighted equivalent continuous sound pressure level (LAeq). Leq 30min was used as the monitoring parameter for the time period between 0700 and 1900 on normal weekdays. Table 2.1 summarizes the monitoring parameters, frequency and duration of the impact noise monitoring.

Table 2.1 Noise Monitoring Parameters, Time, Frequency and Duration

 

Time

Duration

Interval

Parameters

Daytime: 0700-1900

Day time:

0700-1900

(during normal weekdays)

Continuously in

Leq 5min/Leq 30min (average of 6 consecutive Leq 5min)

Leq 30min

L10 30min & L90 30min

 

2.3.      MONITORING LOCATIONS

The monitoring locations should normally be made at a point 1m from the exterior of the NSRs building façade and be at a position 1.2m above the ground. A correction of +3dB(A) should be made to the free-field measurements.

According to the environmental findings detailed in the EIA report and Baseline Monitoring Report, the designated locations for the construction noise monitoring are listed in Table 2.2 below.

Table 2.2 Noise Sensitive Receivers

NSR ID

Noise Sensitive Receivers

Monitoring Location

Position

NSR 4

Creative Secondary School

Roof Floor

1 m from facade

NSR 24

PLK Laws Foundation College

Pedestrian Road on Ground Floor

Free-field

NSR 31

School of Continuing and Professional Studies - CUHK

Roof Floor

1 m from facade

 


The monitoring locations should normally be made at a point 1m from the exterior of the NSRs building façade and be at a position 1.2m above the ground. A correction of +3dB(A) should be made to the free-field measurements. Three noise monitoring locations for impact monitoring at the nearby sensitive receivers are shown in Figure 2.1-2.3.

 

 

 

 

 

Figure 2.1 NSR4 Creative Secondary School

 


 

 

Figure 2.2 NSR24 PLK Laws Foundation College

 

Figure 2.3 NSR31 School of Continuing and Professional Studies - CUHK

 

 


2.4.      ACTION AND LIMIT LEVELS

The Action/Limit Levels are in line with the criteria of Practice Note for Professional Persons (ProPECC PN 2/93) “Noise from Construction Activities - Non-statutory Controls” and Technical Memorandum on Environmental Impact Assessment Process issued by HKSAR Environmental Protection Department [“EPD”] under the Environmental Impact Assessment Ordinance, Cap 499,

S.16 are presented in Table 2.3.

 

Table 2.3    Action and Limit Levels for Construction Noise Monitoring per EM&A Manual

 

Time Period

Action Level

Limit Level (dB(A))

 

0700-1900 on normal weekdays

When one documented complaint is received from any one of the noise sensitive receivers

-          70 dB(A) for school and

-          65 dB(A) during examination period

Notes: Limits specified in the GW-TM and IND-TM for construction and operation noise, respectively.

 

If exceedances were found during noise monitoring, the actions in accordance with the Event and Action Plan shall be carried out according to Appendix E.

 

 

 

 

 

2.5.      MONITORING RESULTS AND OBSERVATIONS

 

Referring to EM&A manual Section 4.1.2, the impact noise monitoring should be carried out when there are project-related construction activities undertaken within a radius of 300m from the monitoring stations. No noise monitoring station was located within a radius of 300m of the Project site as shown in Figure 2.4, no impact monitoring for noise impact was conducted in the reporting period.


 

Figure 2.4        Site Layout Plan with Noise Sensitive Receivers and Desalination Plant
 
 
 
 
 

3.                 WATER QUALITY

 

In accordance with the recommendations of the EIA, water quality monitoring is required during dredging for the submarine pipelines and, during operation phase. In addition, baseline water quality monitoring was conducted prior to the commencement of marine construction activities.

The following Section provides details of the water quality monitoring to be undertaken by the Environmental Team (ET) to verify the distance of sediment and brine plume dispersion and to identify whether the potential exists for any indirect impacts to occur to ecological sensitive receivers. The water quality monitoring programme was carried out to allow any deteriorating water quality to be readily detected and timely action taken to rectify the situation.

Water quality monitoring for the Project can be divided into the following stages:

 

-               Dredging activities during construction phase;

 

-               Discharge of effluent from main disinfection during construction phase;

 

-               Operation phase - first year upon commissioning; and,

 

-               Continuous monitoring of effluent quality.

 

In addition, the marine works contractor is required to complete a silt curtain efficiency test for the combined use of floating silt curtain type and cage type silt curtain for dredging at seawater intake to confirm the silt curtain reduction efficiency assumptions of the assessment. The details of testing plan together with the silt curtain deployment plan shall be submitted by the ET to seek approval from the IEC and EPD.

With the onset of marine dredging activities in late April at Outfall Shaft Area, a silt curtain efficiency test has been conducted at the Outfall Shaft Area on 16t April 2021 at 6 monitoring intervals (08:00, 10:00, 12:00, 14:00, 16:00, 18:00). The baseline monitoring event has been conducted on 10 April 2021 at 5 monitoring locations. Testing protocols and methodologies had followed the guidelines as presented in the EM&A Manual Annex C. Detailed analysis of in-situ and laboratory data was presented in a separate report which has been submitted to EPD after approval by IEC on 31 May 2021. The overall Silt Removal Effectiveness at Outfall Shaft Area for the combined used of cage and floating type silt curtains was 95.28%.

 

3.1.      WATER QUALITY PARAMETERS

The parameters that have been selected for measurement in situ and in the laboratory are those that were either determined in the EIA to be those with the most potential to be affected by the construction works or are a standard check on water quality conditions. Parameters measured in the impact monitoring are listed in Table 3.1.

 

 

 


Table 3.1 Parameters measured in the impact marine water quality monitoring

 

Parameters

Unit

Abbreviation

In-situ measurements

Dissolved oxygen

mg/L

DO

Temperature

oC

-

pH

-

-

Turbidity

NTU

-

Salinity

0/00

-

Total Residual Chlorine NOTE1

mg/L

TRC

Laboratory measurements

Suspended Solids

mg/L

SS

Iron-Soluble NOTE2

mg/L

Fe

Anti-scalant as Reactive Phosphorus NOTE2

mg/L

PO4 as P-

NOTE 1: Monitoring of TRC will be conducted when cleaning and sterilization of the new freshwater main is carried out.

 

In addition to the water quality parameters, other relevant data were measured and recorded in Water Quality Monitoring Logs, including the location of the sampling stations, water depth, time, weather conditions, sea conditions, tidal stage, current direction and velocity, special phenomena and work activities undertaken around the monitoring and works area that may influence the monitoring results.

 

3.1.1.         MONITORING LOCATIONS

The impact water quality monitoring locations in accordance to the EM&A Manual and detailed in

Table 3.2 below.

 

 


Table 3.2 Location of Impact Water Quality Monitoring Station

 

Station

Easting

Northing

Description

CE

843550

815243

Upstream control station at ebb tide

CF

846843

810193

Upstream control station at flood tide

WSR1

846864

812014

Ecological sensitive receiver at Tung Lung Chau

WSR2

847645

812993

Fisheries sensitive receiver at Tung Lung Chau

WSR3

848023

813262

Ecological sensitive receiver at Tung Lung Chau

WSR4

847886

814154

Ecological sensitive receiver at Tai Miu Wan

WSR16

845039

815287

Ecological sensitive receiver at Fat Tong Chau

WSR33

847159

814488

Ecological sensitive receiver at Tai Miu Wan

WSR36

846878

814081

Ecological sensitive receiver at Kwun Tsai

WSR37

846655

813810

Ecological sensitive receiver at Tit Cham Chau

NF1

846542

813614

Edge of mixing zone, ~ 200m west of outfall diffuser

NF2

846942

813614

Edge of mixing zone, ~ 200m east of outfall diffuser

NF3

846742

813414

Edge of mixing zone, ~ 200m south of outfall diffuser

 

 

 

 

 

 

 

Figure 3.1          Impact Water Quality Monitoring Locations under EM&A Manual

 

 


 

3.2.      MONITORING EQUIPMENT, METHODOLOGY AND QA/QC PROCEDURES

 

The monitoring methodology, equipment used and QA/QC procedures could be referring to Section 3.1.2 -3.1.4, 3.1.6-3.1.7 and 3.2 of the Monthly EM&A Report.

 

3.3.      ACTION AND LIMIT LEVELS

The Action and Limit Levels have been set based on the derivation criteria specified in the EM&A Manual and based on the baseline water quality monitoring data and the derivation criteria, the Action/Limit Levels have been derived and are presented in Table 3.3.

Table 3.33       Derived Action and Limit Levels for Water Quality

 

Parameters

Action

Limit

Construction Phase Impact Monitoring

DO in mg/L

Surface and Middle

7.30  mg L-1 Bottom

7.31  mg L-1

Tung Lung Chau Fish Culture Zone

5.1 mgL-1 or level at control station (whichever the lower)

Surface and Middle 4 mg L-1

Bottom 2 mg L-1

Tung Lung Chau Fish Culture Zone

5.0 mgL-1 or level at control station (whichever the lower)

SS         in         mg/L (Depth-averaged)

5.00 mg L-1 or 20% exceedance of value at any impact station compared with corresponding data from control

station

6.00 mg L-1 or 30% exceedance of value at any impact station compared with corresponding data

from control station

Turbidity in NTU (Depth-averaged)

2.41 NTU or 20% exceedance of value at any impact station compared with corresponding data from control

station

2.84 NTU or 30% exceedance of value at any impact station compared with corresponding data

from control station

First-year Operation Phase Monitoring iv

DO in mg/L

Surface and Middle

7.30  mg L-1 Bottom

7.31  mg L-1

Tung Lung Chau Fish Culture Zone

Surface and Middle 4 mg L-1

Bottom 2 mg L-1

Tung Lung Chau Fish Culture Zone

 

5.1 mgL-1 or level at control station

(whichever the lower)

5.0 mgL-1 or level at control station

(whichever the lower)

SS         in         mg/L (Depth-averaged)

5.00 mg L-1 or 20% exceedance of value at any impact station compared with corresponding data from control

station

6.00 mg L-1 or 30% exceedance of value at any impact station compared with corresponding data

from control station

Turbidity in NTU (Depth-averaged)

2.41 NTU or 20% exceedance of value at any impact station compared with corresponding  data  from  control

station

2.84 NTU or 30% exceedance of value at any impact station compared with corresponding data

from control station

Salinity     in     PSU (Depth-averaged)

34.28 PSU or 9% exceedance of value at any impact station compared with corresponding  data  from  control

station

34.60 PSU or 10% exceedance of value at any impact station compared with corresponding data

from control station

Iron in mg/L

(Depth-averaged)

0.3 mgL-1

0.3 mgL-1

Notes:

i.             "Depth-averaged" is calculated by taking the arithmetic means of reading of all three depths.

ii.            For DO, non-compliance of the water quality limits occurs when monitoring result is lower than the limits.

iii.            For Turbidity, SS, iron and Salinity, non-compliance of the water quality limits occurs when monitoring result is higher than the limits.

iv.             For the Action and Limit Levels adopted during First-year Operation Phase Monitoring, further review would be made according to the EM&A Manual during Operation Phase.

 

 

3.4.      MONITORING RESULTS AND OBSERVATIONS

General water quality monitoring at the ten monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36 and WSR37) were conducted on 2/12, 4/12, 7/12, 9/12, 11/12, 14/12, 16/12, 18/12, 21/12, 23/12, 25/12, 28/12, 30/12 and 1/1, 4/1, 6/1, 8/1, 11/1, 13/1, 15/1, 18/1 ,20/1, 22/1, 21/1, 27/1, 29/1, 31/1 and 4/2, 8/2, 10/2, 12/2, 15/2, 17/2, 19/2, 22/02, 24/2 and 26/2.

 

During the impact water quality monitoring period between December 2021 to February 2022, one hundred and ninety-three (193) of the general water quality monitoring results of suspended solids (SS) obtained had exceeded the Action Level. One hundred and thirty-two (132) of the general water quality monitoring results of SS obtained during the reporting quarter had exceeded the Limit Level.

 


Investigation on the reason of exceedance has been carried out, where the exceedances of SS on 2/12, 4/12, 9/12, 11/12, 14/12, 16/12, 18/12, 21/12, 23/12, 25/12, 28/12 and 30/12, 1/01, 4/1, 6/1, 8/1, 11/1, 15/1, 18/1, 20/1, 22/1, 25/1, 27/1, 29/1 and 31/1, 4/2, 8/2, 10/2, 12/2, 15/2, 17/2, 19/2, 22/2, 24/2 and 26/2 were concluded to be unrelated to the project. Details of the instigation could be referring to Monthly EM&A Report Appendix O.

 

 


 

Table 3.4           Summary of Regular Impact Water Quality Monitoring Results (Mid-Flood)

 

 

Location

Parameter

 

Salinity (ppt)

Dissolved Oxygen (mg/L)

 

pH

 

Turbidity (NTU)

Suspended Solids (mg/L)

 

Temp. (oC)

Surface & Middle

Bottom

Dec

Jan

Feb

Dec

Jan

Feb

Dec

Jan

Feb

Dec

Jan

Feb

Dec

Jan

Feb

Dec

Jan

Feb

Dec

Jan

Feb

 

CE

Avg.

32.3

32.8

32.9

8.58

8.8

9.1

8.8

8.8

9.1

8.27

8.2

8.3

3.6

3.3

4.6

4.87

4.1

6.9

23.5

21.1

18.4

Min.

30.6

30.1

30.6

7.89

8.1

8.3

8.1

8.1

8.2

8.05

8.0

8.0

2.7

2.3

3.5

2.50

2.5

2.5

22.1

19.7

16.6

Max

33.4

35.1

34.0

9.82

9.6

10.1

9.6

9.6

10.2

8.42

8.5

8.4

5.2

4.3

6.1

12.0

12.0

20.0

25.8

23.1

20.4

 

CF

Avg.

32.3

32.8

32.9

8.49

8.7

9.1

8.7

8.7

9.1

8.34

8.3

8.3

4.2

3.9

3.7

5.25

5.4

7.5

23.5

21.2

18.5

Min.

30.8

30.3

31.6

7.80

8.2

8.3

8.2

8.2

8.3

8.08

8.0

8.1

3.1

2.2

2.5

2.50

2.5

2.5

21.7

20.1

16.4

Max

33.5

34.9

34.2

9.72

9.0

10.0

9.1

9.1

10.1

8.56

8.5

8.4

6.4

5.7

5.0

14.0

22.0

27.0

25.9

22.9

20.2

 

WSR1

Avg.

32.3

32.8

32.8

8.69

8.7

9.2

8.6

8.6

9.2

8.25

8.2

8.3

2.7

2.7

3.0

5.88

4.4

6.3

23.5

21.1

18.4

Min.

30.2

30.3

30.8

8.16

8.2

8.4

8.2

8.2

8.4

8.08

8.0

8.0

1.3

1.6

1.6

2.50

2.5

2.5

21.7

19.6

16.4

Max

33.7

35.0

34.2

9.16

9.4

10.1

9.4

9.4

10.1

8.47

8.5

8.4

4.1

4.0

4.2

13.0

8.0

19.0

25.5

22.7

20.4

 

WSR2

Avg.

32.3

33.0

32.8

8.59

9.0

9.1

8.9

8.9

9.1

8.28

8.3

8.3

2.8

2.3

2.2

5.31

5.0

7.9

23.6

21.2

18.3

Min.

30.4

31.1

30.9

8.01

8.3

8.3

8.4

8.4

8.3

8.11

8.0

8.1

1.4

1.5

1.8

2.50

2.5

2.5

22.3

19.7

16.6

Max

34.0

35.0

34.0

9.34

9.8

10.1

9.9

9.9

10.2

8.47

8.5

8.5

4.0

3.4

2.9

12.0

21.0

23.0

25.6

23.2

19.9

 

WSR3

Avg.

32.3

32.4

32.8

8.66

8.7

9.0

8.7

8.7

9.0

8.31

8.3

8.2

2.7

2.7

3.0

6.51

6.5

8.1

23.5

23.5

18.3

Min.

31.0

31.1

31.2

7.67

7.7

8.4

7.7

7.7

8.3

8.10

8.1

8.0

1.6

1.6

1.8

2.50

2.5

2.5

21.9

21.9

16.4

Max

33.2

33.3

33.7

9.39

9.4

10.1

9.4

9.4

10.0

8.52

8.5

8.5

4.6

4.6

4.1

23.0

23.0

21.0

25.8

25.8

19.9

 

WSR4

Avg.

32.1

32.7

32.9

8.47

8.8

9.1

8.8

8.8

9.1

8.29

8.2

8.3

2.7

2.7

3.2

6.86

6.4

8.2

23.6

21.2

18.4

Min.

30.9

30.6

31.0

7.72

8.3

8.4

8.0

8.0

8.4

8.06

8.0

8.1

1.6

1.8

2.1

2.50

2.5

2.5

22.1

20.0

16.5

Max

33.4

35.3

34.4

9.11

9.6

10.0

9.6

9.6

10.0

8.50

8.4

8.5

4.2

3.8

4.6

26.0

36.0

22.0

25.9

22.5

20.1

 

WSR16

Avg.

32.2

32.2

33.1

8.75

8.8

8.9

8.8

8.8

8.9

8.29

8.3

8.3

2.9

2.9

3.1

6.42

6.4

7.0

23.6

23.6

18.4

Min.

30.9

31.0

30.8

8.08

8.1

8.4

8.0

8.0

8.4

8.06

8.1

8.1

1.7

1.7

1.5

3.00

3.0

2.5

22.0

22.0

16.6

Max

33.8

33.8

34.2

9.52

9.5

9.7

9.5

9.5

9.8

8.45

8.5

8.5

4.3

4.3

4.0

26.0

26.0

21.0

25.6

25.6

20.4

 

WSR33

Avg.

32.0

32.7

33.0

8.63

8.6

9.0

8.6

8.6

9.0

8.29

8.3

8.3

2.6

2.9

3.2

6.92

4.3

6.4

23.6

21.1

18.4

Min.

30.5

30.6

31.0

8.02

8.0

8.3

8.0

8.0

8.4

8.09

8.0

8.1

1.8

1.8

2.0

3.00

2.5

2.5

22.0

19.9

16.5

Max

33.1

34.3

34.2

9.28

9.0

9.8

9.1

9.1

9.9

8.57

8.5

8.4

3.6

4.3

4.3

24.0

8.0

21.0

26.1

22.6

20.0

 

WSR36

Avg.

32.4

32.7

32.8

8.61

8.9

9.0

8.8

8.8

9.0

8.29

8.3

8.3

2.9

2.7

2.8

7.03

4.9

7.0

23.6

21.1

18.4

Min.

31.1

30.9

31.2

8.00

8.3

8.4

8.2

8.2

8.3

8.11

8.1

8.1

1.6

1.3

1.2

2.50

2.5

2.5

22.1

19.9

16.3

Max

33.7

35.2

33.8

9.17

9.7

10.0

9.8

9.8

10.1

8.56

8.5

8.5

4.4

4.0

4.0

24.0

13.0

25.0

26.2

22.6

20.2

 

WSR37

Avg.

32.2

32.8

32.9

8.68

8.8

9.0

8.8

8.8

9.0

8.29

8.3

8.2

2.7

2.8

2.9

7.95

5.3

5.8

23.6

21.1

18.3

Min.

31.1

30.6

31.4

7.85

8.3

8.3

8.3

8.3

8.3

8.10

8.0

8.0

1.7

1.8

2.1

3.00

2.5

2.5

21.9

19.8

16.5

Max

33.5

35.2

34.3

9.50

9.8

9.8