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/B) 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 56th Monthly 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 October to 31 October 2024.

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 Contract included the followings:

All Area

- Security Fence footing construction work

- Footpath Construction

- Landscape Construction

- Irrigation System Construction

- Water Pressure Test for FS and PL system

- Landscape planting work

- Traffic signage work

- E&M Works and Mechanical Installation

PWST

- Water Test in Tank A

- Waterproofing work at Roof Slab on Tank A

- Installation of building services, electrical switchboards and cables

- Installation of mechanical equipment, steel pipe, Pressure Test

Administration Building

- External wall aluminum features installation

- Finishing works for dog house

- Minor Installation of building services, electrical switchboards & cables, Pressure Test, T&C

Chemical building

- Defect rectification

- Repairing the defects inside the dangerous store

Combined Shaft & Pump House

- Internal finishing, defect rectification

- Construction of hose reel cabinet

- T&C

ActiDAFF

- Installation of access opening covers for filtered water tank

- Carrying out finishing works for staircase no. 3.

- Minor Installation of mechanical equipment, piping system

- Minor Installation of building services, electrical switchboards and cables, Installation of FRP Enclosure System

Product Water Storage Tank Building

- Minor Installation of building services, cable laying and termination, PV Panel Installation, Testing & Commissioning

OSCG Building

- Protective Coating for DG Rooms

- Installation of Railing on Brine Maker Tank

- Minor Installation of building services, cables and pipe works, T&C

- Tank surface cleaning, T&C

Reverse Osmosis Building

- Installation of Signage, AP doors, sanitary fitting, sanitary ware in toilet, tiling work and water meter cabinets

- Minor Installation of building services, minor cable laying and termination,

Testing & Commissioning, PV Panel Installation

Post Treatment Building

- Installation of Cat Ladders in Water Tanks

- Placing Soil Mix at Roof

- Curb Construction for Rescue Opening at Water Tanks

- Installation of building services, piping system, mechanical equipment and piping system, Pressure Test

Inspection gallery

- Construction of roof tiling works

- Installation of steel balustrade at roof

- Installation of movement joints

- Construction of block works

- Minor Installation of building service, T&C

RO and Electrical Building

- Installation of Glass House

- Minor Installation of building services, electrical switchboards and cables

- Minor Installation of mechanical pipework and raised Floor,

- PV Panel Installation, T&C

Chiller plant & Main Electrical Building

- Minor Installation of building services, electrical switchboards and cables, Pressure Test, T&C

Others

- Slope works

- Construction works of extended access road

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

- Construction dust and noise generation from construction works and excavation works and slope works;

- Waste generation from the construction activities

A7. The key environmental mitigation measures implemented for the Contract 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 regular inspection to machinery and plants/vehicles on-site to ensure proper functioning;

- Deployment of silt curtain at the inshore water outflow;

- Sorting and storage of general refuse and construction waste; and

- Deployment protective fencing for trees

Summary of exceedance & investigation & follow-up

A8. No noise monitoring was conducted during the reporting period since there are no Contract -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 construction phase marine water quality programme was ceased from 1 September 2023 due to the completion of marine-related construction works.

A10. Water quality monitoring of the discharge of dechlorinated effluent in disinfection procedure is completed in December 2023. The hourly dechlorinated effluent monitoring during the discharge is finished.

A11. In this reporting period, 63 times of landfill gas monitoring were periodically conducted at TKO Area 137 (Ch1+120 - Ch1+800) until 31 October 2024. No exceedances of action level and limit level was observed.

A12. Joint site inspections of the construction work by ET and IEC were carried out on 28 October 2024 to audit the mitigation measures implementation status.

Complaint Handling and Prosecution

A13. No environmental complaint, notification of summons and prosecution was received in the reporting period.

Reporting Change

A14. According to the contractor’s information, the TKODP commenced operation phase on 1 July 2024. The outstanding construction works were being carried out during this reporting period.

Summary of Upcoming Key Issues and Key Mitigation Measures

A15. Key activities anticipated in the next reporting period for the Contract will include the followings:

All Area

- Security Fence footing construction work

- Footpath Construction

- Landscape Construction

- Irrigation System Construction

- Water Pressure Test for FS and PL system

- Landscape planting work

- Traffic signage work

- E&M Works and Mechanical Installation

PWST

- Water Test in Tank A

- Waterproofing work at Roof Slab on Tank A

- Installation of building services, electrical switchboards and cables

- Installation of mechanical equipment, steel pipe, Pressure Test

Administration Building

- External wall aluminum features installation

- Finishing works for dog house

- Minor Installation of building services, electrical switchboards & cables, Pressure Test, T&C

Chemical building

- Defect rectification

- Repairing the defects inside the dangerous store

Combined Shaft & Pump House

- Internal finishing, defect rectification

- Construction of hose reel cabinet

- T&C

ActiDAFF

- Installation of access opening covers for filtered water tank

- Carrying out finishing works for staircase no. 3.

- Minor Installation of mechanical equipment, piping system

- Minor Installation of building services, electrical switchboards and cables, Installation of FRP Enclosure System

Product Water Storage Tank Building

- Minor Installation of building services, cable laying and termination, PV Panel Installation, Testing & Commissioning

OSCG Building

- Protective Coating for DG Rooms

- Installation of Railing on Brine Maker Tank

- Minor Installation of building services, cables and pipe works, T&C

- Tank surface cleaning, T&C

Reverse Osmosis Building

- Installation of Signage, AP doors, sanitary fitting, sanitary ware in toilet, tiling work and water meter cabinets

- Minor Installation of building services, minor cable laying and termination,

Testing & Commissioning, PV Panel Installation

Post Treatment Building

- Installation of Cat Ladders in Water Tanks

- Placing Soil Mix at Roof

- Curb Construction for Rescue Opening at Water Tanks

- Installation of building services, piping system, mechanical equipment and piping system, Pressure Test

Inspection gallery

- Construction of roof tiling works

- Installation of steel balustrade at roof

- Installation of movement joints

- Construction of block works

- Minor Installation of building service, T&C

RO and Electrical Building

- Installation of Glass House

- Minor Installation of building services, electrical switchboards and cables

- Minor Installation of mechanical pipework and raised Floor,

- PV Panel Installation, T&C

Chiller plant & Main Electrical Building

- Minor Installation of building services, electrical switchboards and cables, Pressure Test, T&C

Others

- Construction works of extended access road

A16. The major environmental impacts brought by the above construction works will include:

- Construction dust and noise generation from excavation and construction works;

- Waste generation from construction activities.

A17. The key environmental mitigation measures for the Contract in the coming reporting period associated with the above construction works will include:

- Reduction of noise from equipment and machinery on-site;

- Dust suppression by regular wetting and water spraying for construction works and at main haul road;

- Sorting and storage of general refuse and construction waste;

- Deployment of silt curtain at the inshore water outflow;

- Deployment protective fencing for trees.

1. Basic Contract Information

Background

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

1.2. 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.

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

1.4. According to the contractor’s information, the TKODP commenced operation phase on 1 July 2024. The outstanding construction works were being carried out during this reporting period.

The Reporting Scope

1.5. This is the 56th Monthly EM&A Report for the Contract which summarizes the key findings of the EM&A programme during the reporting period from 1 October to 31 October 2024.

Contract Organization

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

Figure 1.1 Contract Organization Chart

1.7. 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.

Contract Proponent (Water Supplies Department)

SE/CM2

Milton Law

2634-3573

Supervising Officer (Binnies Hong Kong Limited)

Project Manager

Augustine Li

2608-7671

Chief Resident Engineer

David Wong

5229-8638

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

Operation Manager

Arnes Parra, Victor

6468-6710

Environmental Monitoring Manager

Tommy Law

6468-1782

Acuity Sustainability Consulting Limited

Environmental Team Leader

Toby Wan

9719-5422

Lam Environmental Services Limited

Independent Environmental Checker (IEC)

Serena Shek

6149-6683

Summary of Construction Works

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

1.9. Key activities carried out in this reporting period for the Contract included the followings:

All Area

- Security Fence footing construction work

- Footpath Construction

- Landscape Construction

- Irrigation System Construction

- Water Pressure Test for FS and PL system

- Landscape planting work

- Traffic signage work

		- E&M Works and Mechanical Installation
		PWST - Water Test in Tank A - Waterproofing work at Roof Slab on Tank A - Installation of building services, electrical switchboards and cables - Installation of mechanical equipment, steel pipe, Pressure Test
		Administration Building - External wall aluminum features installation - Finishing works for dog house - Minor Installation of building services, electrical switchboards & cables, Pressure Test, T&C
		Chemical building - Defect rectification - Repairing the defects inside the dangerous store
		Combined Shaft & Pump House - Internal finishing, defect rectification - Construction of hose reel cabinet - T&C
		ActiDAFF - Installation of access opening covers for filtered water tank - Carrying out finishing works for staircase no. 3. - Minor Installation of mechanical equipment, piping system - Minor Installation of building services, electrical switchboards and cables, Installation of FRP Enclosure System
		Product Water Storage Tank Building - Minor Installation of building services, cable laying and termination, PV Panel Installation, Testing & Commissioning
		OSCG Building - Protective Coating for DG Rooms - Installation of Railing on Brine Maker Tank - Minor Installation of building services, cables and pipe works, T&C - Tank surface cleaning, T&C
		Reverse Osmosis Building - Installation of Signage, AP doors, sanitary fitting, sanitary ware in toilet, tiling work and water meter cabinets - Minor Installation of building services, minor cable laying and termination, Testing & Commissioning, PV Panel Installation
		Post Treatment Building - Installation of Cat Ladders in Water Tanks - Placing Soil Mix at Roof
	- Curb Construction for Rescue Opening at Water Tanks - Installation of building services, piping system, mechanical equipment and piping system, Pressure Test
	Inspection gallery - Construction of roof tiling works - Installation of steel balustrade at roof - Installation of movement joints - Construction of block works - Minor Installation of building service, T&C
	RO and Electrical Building - Installation of Glass House - Minor Installation of building services, electrical switchboards and cables - Minor Installation of mechanical pipework and raised Floor, - PV Panel Installation, T&C Chiller plant & Main Electrical Building - Minor Installation of building services, electrical switchboards and cables, Pressure Test, T&C Others - Slope works - Construction works of extended access road
1.10. A summary of the valid permits, licences, and/or notifications on environmental

protection for this Contract is presented in Table 1.2.

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

Permit/ Licences	Valid Period		Status	Remark
Permit/ Licences	From	To	Status	Remark
Environmental Permit
EP-503/2015/B	Throughout the Contract		Valid	-Issued on 3 April 2024
FEP - 01/503/2015/B	Throughout the Contract		Valid	-Issued on 3 April 2024
Notification of Construction Works under the Air Pollution Control (Construction Dust) Regulation (Form NA)
451539	Throughout the Contract		Valid	-
Billing Account for Disposal of Construction Waste
7036276	Throughout the Contract		Valid	-
Sludge (Special Waste) Disposal (Admission Ticket)
17913	01/07/2024	31/12/2024	Valid	-
17372	12/06/2024	31/12/2024	Valid	-
Chemical Waste Producer Registration
5213-839-A2987- 01	Throughout the Contract		Valid	-
Wastewater Discharge Licence (Land and Marine works)
WT00035775-2020	23/08/2021	31/07/2025	Valid	-
WT00044188-2023	16/06/2023	30/06/2028	Valid	- For Plant T&C and operation. - Variation sampling point S.P.1 is approved by the EPD on 25 June 2024 (EPD ref.: EP640/W3/D1358/46 2874). - The variation of application of discharge license was submitted on 9 September 2024 and pending for EPD approval
Construction Noise Permit
GW-RE0667-24	22/06/2024	20/12/2024	Valid	-

1.11. 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 Manual	under	EM&A	The baseline water quality monitoring was conducted between 12 May 2020 to 6 Jun 2020.
Construction Phase Impact Monitoring			Ceased from 1 September 2023
Operation phase Monitoring	Marine	Impact	On-going
Impact Monitoring of Effluent Discharge from Main Disinfection			Completed
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			Completed
Waste Management
Mitigation Measures in Waste Management Plan			On-going
Landfill Gas
Regular Monitoring when construction works are within the 250 m Consultation Zone			On-going
Ecology (Coral)
Operation phase Regular Coral Monitoring (Monthly)			On-going
Ecology (Fishery)
Operation phase Regular Fishery Monitoring (Seasonally)			On-going
Ecology (Landscape)
Operation phase Landscape and Visual Site Inspection			On-going
Environmental Audit
Site Inspection covering Measures of Air Quality, Noise Impact, Water Quality, Waste, Ecological Quality, Fisheries, Landscape and Visual			On-going

1.12. 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.

1.13. 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 Contract during the reporting period is provided in Appendix C.

2. Noise

Monitoring Requirements

2.1. To ensure no adverse noise impact, 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.

2.2. Construction noise level were 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. Construction works would follow stipulations of the valid Construction Noise Permits if works had to be conducted during restricted hours or public holidays. 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

Monitoring Locations

2.3. The monitoring locations were normally 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.

2.4. 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

2.5. 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

Impact Monitoring Methodology

2.6. Integrated sound level meter will be used for the noise monitoring. The meter will be in compliance with the International Electrotechnical Commission Publications 651: 1979 (Type 1) and 804: 1985 (Type 1) specifications. Immediately prior to and following each noise measurement the accuracy of the sound level meter will be checked using an acoustic calibrator generating a known sound pressure level at a known frequency. Measurements will be accepted as valid only if the calibration levels before and after the noise measurements agree to within 1.0 dB(A).

2.7. Noise measurements were not made in the presence of fog, rain, wind with a steady speed exceeding 5 m/s or wind with gusts exceeding 10 m/s. The wind speed shall be checked with a portable wind speed meter capable of measuring the wind speed in m/s.

Action and Limit Levels

2.8. 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 Noise per EM&A Manual

Time Period

Action

Limit (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

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

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

Monitoring Results and Observations

2.10. Referring to EM&A Manual Section 4.1.2, the impact noise monitoring should be carried out when there are Contract-related construction activities undertaken within a radius of 300m from the monitoring stations. As no Contract-related construction activities were undertaken in the reporting month within a radius of 300m from the monitoring stations as shown in Figure 2.4, no impact noise monitoring was conducted in the reporting period.

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

3. Water Quality

3.1. In accordance with the recommendations of the EIA, water quality monitoring is required during dredging for the submarine pipelines and, during operation phase. 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.

3.2. The water quality monitoring programme was be carried out to allow any deteriorating water quality to be readily detected and timely action taken to rectify the situation.

3.3. Water quality monitoring for the Contract can be divided into the following stages:

- Dredging activities during construction phase;

- Discharge of effluent from main disinfection during construction phase; and

- Operation activities during operation phase.

Water Quality Parameters

3.4. 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 to be 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	mg/L	Fe
Anti-scalant as Reactive Phosphorus	mg/L	PO4 as P-

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

3.5. In addition to the water quality parameters, other relevant data were also being 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.

Monitoring Equipment

3.6. For water quality monitoring, the following equipment were used:

Dissolved Oxygen and Temperature Measuring Equipment - The instrument was a portable, weatherproof dissolved oxygen measuring instrument complete with cable, sensor, comprehensive operation manuals, and was operable from a DC power source. It was capable of measuring: dissolved oxygen levels in the range of 0 - 20 mg/L and 0 - 200% saturation; and a temperature of 0 - 45 degrees Celsius. It has a membrane electrode with automatic temperature compensation complete with a cable of not less than 35 m in length. Sufficient stocks of spare electrodes and cables were available for replacement where necessary (e.g. YSI model 59 DO meter, YSI 5739 probe, YSI 5795A submersible stirrer with reel and cable or an approved similar instrument).

Turbidity Measurement Equipment - The instrument was a portable, weatherproof turbidity-measuring unit complete with cable, sensor and comprehensive operation manuals. The equipment was operated from a DC power source, it has a photoelectric sensor capable of measuring turbidity between 0 - 1000 NTU and complete with a cable with at least 35 m in length (for example Hach 2100P or an approved similar instrument).

Salinity Measurement Instrument - A portable salinometer capable of measuring salinity in the range of 0 - 40 ppt was provided for measuring salinity of the water at each monitoring location.

Water Depth Gauge - A portable, battery-operated echo sounder (for example Seafarer 700 or a similar approved instrument) was used for the determination of water depth at each designated monitoring station. This unit will preferably be affixed to the bottom of the work boat if the same vessel is to be used throughout the monitoring programme. The echo sounder was suitably calibrated.

Positioning Device - A Global Positioning System (GPS) was used during monitoring to allow accurate recording of the position of the monitoring vessel before taking measurements. The Differential GPS, or equivalent instrument, was suitably calibrated at appropriate checkpoint (e.g. Quarry Bay Survey Nail) to verify that the monitoring station is at the correct position before the water quality monitoring commence.

Water Sampling Equipment - A water sampler, consisting of a PVC or glass cylinder of not less than two litres, which can be effectively sealed with cups at both ends, was used. The water sampler has a positive latching system to keep it open and prevent premature closure until released by a messenger when the sampler is at the selected water depth.

Total Residual Chlorine -Total residual chlorine (TRC) shall be measured in-situ using approved test kit.

Sampling / Testing Protocols

3.7. All in situ monitoring instruments were checked, calibrated, and certified by a laboratory accredited under HOKLAS or any other international accreditation scheme before use, and subsequently re-calibrated at monthly intervals throughout the stages of the water quality monitoring. Responses of sensors and electrodes were checked with certified standard solutions before each use.

3.8. On-site calibration of field equipment was following the “Guide to On-Site Test Methods for the Analysis of Waters”, BS 1427: 2009. Sufficient stocks of spare parts were maintained for replacements when necessary. Backup monitoring equipment was made available so that monitoring can proceed uninterrupted even when equipment is under maintenance, calibration etc.

Laboratory Measurement and Analysis

3.9. Sufficient volume of each water sample was collected for carrying out the laboratory analyses. Using chain of custody forms, collected water samples were transferred to a HOKLAS accredited laboratory (Acumen Laboratory and Testing Limit - HOKLAS 241) for immediate processing. The determination work was start within the next working day after collection of the water samples. Analytical methodology and sample preservation of other parameters were based on the latest edition of Standard Methods for the Examination of Waste and Wastewater published by APHA, AWWA and WPCF and methods by USEPA, or suitable method in accordance with requirements of HOKLAS or another internationally accredited scheme. The QA/QC details were in accordance with the requirements of HOKLAS or another internationally accredited scheme.

3.10. Parameters for laboratory measurements, standard methods and detection limits are presented in Table 3.2.

Table 3.2 Laboratory measurements, standard methods, and corresponding detection limits of marine water quality monitoring

Parameters	Standard Methods	Detection Limit	Reporting Limit	Precision
Dissolved oxygen	Instrumental, CTD	0.1	-	+-25%
Temperature	Instrumental, CTD	0.1	-	+-25%
pH	Instrumental, CTD	0.1	-	+-25%
Turbidity	Instrumental, CTD	0.1	-	+-25%
Salinity	Instrumental, CTD	0.1	-	+-25%
Suspended Solids	APHA 23rd Ed 2540D	1.0	2.5	+-17%
Iron	APHA 3111 B	0.2	-	+-25%
Total residual chlorine	Test Kit (Lovibond MD200)	Lowest limit = 0.01mg/L; Upper limit = 6 mg/L	-	+-25%

Monitoring Location

Construction Phase

3.11. The Impact water quality monitoring was ceased from 1 September 2023 due to the completion of marine-related construction works.

Operation phase

3.12. The operation phase impact water quality monitoring locations are in accordance with the EM&A Manual and detailed in Table 3.3 below. A schedule for water quality monitoring was prepared by the ET and submitted to IEC and EPD prior to the commencement of the monitoring.

Table 3.3 Location of Impact Water Quality Monitoring Stations

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

3.13. WSR1 to WSR37 were identified in accordance with Annex 14 of the EIAO-TM as well as Clause 3.4.4.2 of the Environmental Impact Assessment Study Brief for Desalination Plant at Tseung Kwan O (No. ESB-266/2013). WSR1 to WSR3 are sited near the Tung Lung Chau Fish Culture Zone; WSR16 and WSR36 are sited near the coral assemblages along the coastlines of Fat Tong Chau and Kwun Tsai respectively; WSR 4 and WSR33 are sited near the Coastal Protection Area and coral assemblages in waters of Tai Miu Wan; WSR37 is sited near the fisheries resource including spawning and nursery grounds at the coastal water of Tit Cham Chau. NF1 to NF3 are the Edge of Mixing zone.

Figure 3.1 Impact water quality monitoring locations under EM&A Manual

Sampling Frequency

Operation phase

3.14. Impact water quality monitoring were carried out three days per week during the commission phase. Monitoring at each station was undertaken once per day. The interval between two sets of monitoring was not less than 36 hours. The monitoring frequency would be increased in the case of exceedances of Action/Limit Levels if considered necessary by ET. Monitoring frequency would be maintained as far as practicable.

Sampling Depths & Replication

3.15. During impact water quality monitoring, each station was sampled, and measurements/ water samples were taken at three depths, 1 m below the sea surface, mid-depth, and 1 m above the seabed. For in situ measurements, duplicate readings were made at each water depth at each station. Duplicate water samples were collected at each water depth at each station.

Action and Limit Levels

Operation phase

3.16. The Action and Limit Levels have been set based on the derivation criteria specified in the EM&A Manual. The Action/Limit Levels have been derived and are presented in Table 3.4.

Table 3.4 Derived Action and Limit Levels for Water Quality

Parameters	Action	Limit
Operation 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
Salinity in PSU (Depth- averaged)	34.25 PSU or 9% exceedance of value at any impact station compared with corresponding data from control station	34.56 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 mg/L	0.3 mg/L
Total residual chlorine in mg/L	0.01 mg/L	0.01 mg/L

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. Monitoring of Total Residual Chlorine (Disinfection) will be conducted when cleaning and sterilization of the new freshwater main is carried out.

Monitoring Results and Observations

Construction Phase

3.17. Referring to EM&A Manual, the general water quality monitoring should be carried out when there are marine-related construction activities undertaken. General water quality monitoring at the ten monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36 and WSR37) was ceased from 1 September 2023 due to the completion of marine-related construction works.

Operation phase

3.18. According to the contractor’s information, the operation phase of TKODP commenced on

1 July 2024. Details of the operation phase marine water quality monitoring and continuous monitoring of effluent quality will be presented in the Operation Monthly EM&A Report.

4. Waste

4.1. The waste generated from this Contract includes inert construction and demolition (C&D) materials, and non-inert C&D materials. Non-inert C&D materials are made up of general refuse, vegetative wastes and recyclable wastes such as plastics and paper/cardboard packaging waste. Steel materials generated from the Contract are also grouped into non-inert C&D materials as the materials were not disposed of with other inert C&D materials. With reference to relevant handling records and trip tickets of this Contract, the quantities of different types of waste generated in the reporting month are summarized in Table 4.1. Details of cumulative waste management data are presented as a waste flow table in Appendix G.

Table 4.1 Quantities of Waste Generated from the Contract during the reporting period

Reporting Month	Actual Quantities of Inert C&D Materials Generated Monthly						Actual Quantities of C&D Wastes Generated Monthly
	Total Quantity Generated	Hard Rock and Large Broken Concrete	Reused in the Contract	Reused in other Projects	Disposed as Public Fill	Imported Fill	Metals	Paper / cardboard packaging	Plastics (1)	Chemical Waste	Others, e.g., general refuse
	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)	(in ’000kg)
Oct 2024	78.140	0.000	0.000	0.000	78.140	0.000	0.000	0.000	0.000	0.000	71.810

Notes: (1) Plastics refer to plastic bottles / containers, plastic sheets / foam from packaging material

5. Landfill Gas Monitoring

Monitoring Requirement

5.1. In accordance with Section 11 of the EM&A Manual, monitoring of landfill gas is required for construction works within the 250m Consultation Zone. Part of the desalination plant and the indicative area of natural slope mitigation works fall within the SENT Landfill Extension Consultation Zone; and part of the 1,200 mm diameter fresh water mains along Wan Po Road falls within the SENT Landfill and SENT Landfill Extension Consultation Zones, TKO Stage II/III Restored Landfill and TKO Stage I Restored Landfill Consultation Zones.

Monitoring Programme

5.2. Since part of the desalination plant (Wan Po Road and MIC compound/Basketball Court) and the indicative area of natural slope mitigation works fall within the SENT Landfill Extension Consultation Zone in this contract (Figure 5.1), landfill gas monitoring would be required for Wan Po Road and MIC compound/Basketball Court (Figure 5.2) if excavations were conducted at more than 300mm deep. Although SENT Landfill Extension has commenced operation since November 2021, no excavation works were conducted at MIC compound/Basketball Court. Hence no landfill gas monitoring would be scheduled for MIC compound/Basketball Court at the current stage.

Monitoring Location

5.3. Monitoring of oxygen, methane, carbon dioxide and barometric pressure would be performed for excavations at 1m depth or more within the consultation Zone.

5.4. During construction of works within the consultation zones, excavations of 1m depth or more was monitored:

- At the ground surface before excavation commences;

- Immediately before any worker enters the excavation;

- At the beginning of each working day for the entire period the excavation remains open; and

- Periodically through the working day whilst workers are in the excavation.

5.5. For excavations between 300mm and 1m deep, measurements were carried out:

- Directly after the excavation has been completed; and

- Periodically whilst the excavation remains open.

5.6. The area required to be monitored for landfill gas in the reporting period is shown in Figure 5.1.

Map Description automatically generated Figure 5.1 Overview of the SENT Extension Consultation Zone and the Contract Site Area

MONITORING PARAMETERS

5.7. The landfill gas monitoring parameters and the action and limit level are summarized in Table 5.1.

Table 5.1 Action and Limit Level for Landfill Gas Monitoring Equipment

Parameters	Action Level	Limit Level
Oxygen (O2)	<19% O2	<19% O2
Methane (CH4)	>10% LEL	>20% LEL
Carbon Dioxide (CO2)	>0.5% CO2	>1.5% CO2

MONITORING EQUIPMENT

5.8. Landfill Gas monitoring was carried out using intrinsically-safe, portable multi-gas monitoring instruments. The gas monitoring equipment is:

- Complying with the Landfill Gas Hazard Assessment Guidance Note as intrinsically safe;

- Capable of continuous barometric pressure and gas pressure measurements;

- Normally operated in diffusion mode unless required for spot sampling, when it should be capable of operating by means of an aspirator or pump;

- Having low battery, fault and over range indication incorporated;

- Capable of storing monitoring data, and shall be capable of being downloaded directly;

- Measure in the following ranges:

Rev.	Description of Modification	Date
1.	Awaiting for comments	07/11/2024
2.	Revised according to the comments	11/11/2024

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	Event/Action Plan
Appendix E	Landfill Gas Equipment Calibration Certificate
Appendix F	Landfill Gas Monitoring Data
Appendix G	Waste Flow Table
Appendix H	Site Inspection Proforma
Appendix I	Complaint Log
Appendix J	Exceedance Report

methane	0-100% Lower Explosion Limit (LEL) and 0-100% v/v;
oxygen	0-25% V/V;
carbon dioxide	0-5% v/v; and
barometric pressure	mBar (absolute)