Executive Summary

To support the increased use of natural gas in Hong Kong from 2020 onwards, Castle Peak Power Company Limited (CAPCO) and The Hongkong Electric Co., Ltd. (HK Electric) have identified that the development of an offshore liquefied natural gas (LNG) receiving terminal in Hong Kong using Floating Storage and Regasification Unit (FSRU) technology (‘the Project’) presents a viable additional gas supply option that will provide energy security through access to competitive gas supplies from world markets. The Project involves the construction and operation of an offshore LNG import facility to be located in the southern waters of Hong Kong, a double berth jetty, and subsea pipelines that connect to the gas receiving stations (GRS) at the Black Point Power Station (BPPS) and the Lamma Power Station (LPS). The Project commenced operation on 3 July 2023. In accordance with the Updated EM&A Manual of the Project, operation phase water quality monitoring is undertaken during the first year of operation for the Project. This is the water quality monitoring report presenting the operation phase water quality monitoring carried out between January and March 2024.

During the reporting period, operation phase water quality monitoring was conducted at three monitoring locations once per week for 13 sessions between 2 January and 28 March 2024. There were no Project-related Action and Limit Level exceedances for the operation phase water quality monitoring in the reporting period. Overall, deterioration of water quality and indirect impacts at water and ecological sensitive receivers were not detected. The operation of the Project did not result in unacceptable water quality impacts to the nearby water and ecological sensitive receivers, which aligns with the EIA study predictions.

There were no environmental complaints, notification of summons and successful prosecutions recorded for the operation of the Project in the reporting period.

The monitoring activities conducted in the reporting period have been reviewed and are considered effective. As such, no change to the monitoring methodology is recommended. Based on the EM&A findings for the reporting period, the environmental performance for the operation of the Project is generally in line with the EIA predictions and considered acceptable.

1. Introduction

1.1 Background

The Environmental Impact Assessment (EIA) Report for the Project was submitted to the Environmental Protection Department (EPD) of the HKSAR Government in May 2018. The EIA Report (EIAO Register No. AEIAR-218/2018) was approved by EPD and the associated Environmental Permit (EP) (EP-558/2018) was issued in October 2018.

An application for Further Environmental Permits (FEPs) were made on 24 December 2019 to demarcate the works between the different parties. The following FEPs were issued on 17 January 2020 and the EP under EP-558/2018 was surrendered on 5 March 2020.

n the double berth jetty at LNG Terminal under the Hong Kong LNG Terminal Limited (HKLTL), joint venture between CAPCO and HK Electric (FEP-01/558/2018/A) ([1]⁾ – construction commenced on 27 November 2020;

n the subsea gas pipeline for the BPPS and the associated GRS in the BPPS under CAPCO (FEP-03/558/2018/B) ([2]⁾ – construction commenced on 23 September 2020; and

n the subsea gas pipeline for the LPS and the associated GRS in the LPS under HK Electric (FEP-02/558/2018/A)⁽[3]⁾– construction commenced on 13 December 2020.

The location of these components is shown in Figure 1.1.

The Project commenced operation on 3 July 2023. This is the quarterly report for the operation phase water quality monitoring for the LNG Terminal which summarises the key monitoring results for the reporting period of January to March 2024 in accordance with the Updated EM&A Manual of the Project.

1.2 Structure of the Report

The remainder of the report is structured as follows:

n Section 2 details the monitoring locations, monitoring methodology, QA/QC requirements, and the monitoring results;

n Section 3 provides the conclusion of this operation phase water quality monitoring.

2. Operational Phase Water Quality Monitoring

In accordance with the Updated EM&A Manual of the Project, operation phase water quality monitoring would be conducted once a week for one year after operation of the LNG Terminal. Details of the operation phase water quality monitoring under this Project are presented in the following sections.

2.1 Monitoring Locations

Operation phase water quality monitoring was conducted at 3 monitoring stations around the LNG Terminal, comprising 1 sensitive receiver station, 1 ebb-tide control station and 1 flood-tide control station. The locations of the monitoring stations are presented in Figure 2.1. The coordinates and description of monitoring stations are summarised in Table 2.1.

Table 2.1 Location of Water Quality Monitoring Stations

Station	Easting	Northing	Description
IM6	814073	802029	Boundary of South Lantau Marine Park
E2	813367	808213	Control Station for Ebb Tide
F3	815032	801161	Control Station for Flood Tide

2.2 Monitoring Methodology

2.2.1 Monitoring Parameters and Frequency

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 highest potential to be affected by the Project or are a standard check on water quality conditions. Table 2.2 summarises the monitoring parameters, monitoring period and frequencies of the water quality monitoring. The measurement of monitoring parameters followed the standard methods and detection limit requirements as stated in Table 5.2 of the Updated EM&A Manual.

Table 2.2 Water Qaulity Monitoring Parameters and Frequency

Monitoring Station

Parameters

Depth

Frequency and Replication

Sensitive Receiver Station

IM6

Control Stations

Ebb tide - E2

Flood tide - F3

· Dissolved Oxygen (DO) (mg/L)

· Dissolved Oxygen Saturation (DOS) (%)

· Temperature (°C)

· pH

· Turbidity (NTU)

· Salinity (ppt)

· Water depth (m)

· Total Residual Chlorine (TRC) (mg/L)

· Suspended Solid (SS) (mg/L)

· Total Inorganic Nitrogen (TIN) (mg/L)

· 5-day Biochemical Oxygen Demand (BOD₅) (mg/L)

· Three water depths: 1 m below sea surface, mid-depth and 1 m above seabed.

· If the water depth is less than 3 m, mid-depth sampling only.

· If water depth less than 6 m, mid-depth would be omitted.

· First year of operation water quality monitoring: one day per week, at mid-flood and mid-ebb tides, for one year upon the commencement of operation of the LNG Terminal. The interval between two sets of monitoring shall not be less than 36 hours.

· Two replicates of in-situ measurements and water samples at each depth at each station.

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

2.2.2 Monitoring Equipment

Table 2.3 summarises the equipment used in the monitoring works. All the monitoring equipment complied with the requirements as set out in the Updated EM&A Manual.

Table 2.3 Water Qaulity Monitoring Equipment

Equipment	Brand and Model
Water Sampling Equipment	SBE 32 Carousel Water Sampler
Positioning Device	Hemisphere Vector V500
Water Depth Gauge	Knudsen 320M Single Beam Echo Sounder
Equipment for Dissolved Oxygen, Temperature, Turbidity, pH and Salinity measurements	YSI 6820, S/N: MPP16, MPP57, MPP15, MPP46 ^{(Note 1)}
Total Residual Chlorine	Hanna Instruments (Model HI761)
Equipment for Current Velocity and Direction measurements	Teledyne RDI Workhorse Sentinel ADCP

Note 1:

MPP16 was deployed for the monitoring conducted between 2 January 2024 and 15 February 2024, except 31 January and 8 February 2024;

MPP57 was deployed for the monitoring conducted on 31 January 2024;

MPP15 was deployed for the monitoring conducted on 8 February 2024;

MPP46 was deployed for the monitoring conducted between 23 February 2024 and 28 March 2024.

2.2.3 Operational/ Analytical Procedures

At each monitoring station, two consecutive measurements of DO level, DO Saturation, Temperature, Turbidity, Salinity and pH were taken at each sampling depth. Where the difference in the value between the first and second readings of each set was more than 25% of the value of the first reading, the reading was discarded, and further readings were taken. Two water samples were collected for laboratory analysis of SS, TIN and BOD₅. Following sample collection, water samples were stored in high density polythene bottles (1L) with no preservatives added, packed in ice (cooled to 4°C without being frozen) and kept in dark during both on-site temporary storage and transfer to the testing laboratory. The samples were delivered to the laboratory as soon as possible and the laboratory determination works started within 24 hours after collection of the water samples.

The testing of SS, TIN and BOD₅ for all monitoring stations was conducted by a Hong Kong Laboratory Accreditation Scheme (HOKLAS) accredited laboratory, ALS Technichem (HK) Pty Ltd. (HOKLAS Registration No. 066). Comprehensive quality assurance and control procedures were in place in order to ensure quality and consistency in results.

2.2.4 Action and Limit Levels for Marine Water Quality Monitoring

The Action and Limit Levels for operation phase water quality monitoring have been established with reference to Table 5.5 of the Updated EM&A Manual. Action and Limit Levels of key assessment parameters for operation phase marine water quality monitoring are summarised in Table 2.4 which have been agreed with EPD.

Table 2.4 Action and Limit Levels for Operation Phase Water Quality Monitoring

Parameters	Action Level	Limit Level
*First-year Operation Phase Water Quality Monitoring*
DO in mg L^{-1 a}	Surface and Middle 4.0 mg L^-1 Bottom 2.2 mg L^-1	Surface and Middle 3.0 mg L^-1 Bottom 1.5 mg L^-1
Water Temperature in °C (Depth-averaged^b)^c	± 1.5 °C of baseline data, and ± 1.5 °C of the relevant control station's water temperature at the same tide of the same day	± 2.0 °C of baseline data, and ± 2.0 °C of the relevant control station's water temperature at the same tide of the same day
Turbidity in NTU (Depth-averaged^b)^c	18.3 NTU, and 120% of the relevant control station's turbidity at the same tide of the same day	30.8 NTU, and 130% of the relevant control station's turbidity at the same tide of the same day
SS in mg L^-1 (Depth-averaged^b)^c	17.5 mg L^-1, and 120% of the relevant control station's SS at the same tide of the same day	29.5 mg L^-1, and 130% of the relevant control station's SS at the same tide of the same day
TIN in mg L^-1 (Depth-averaged^b)^c	0.5 mg L^-1, and 120% of the relevant control station's TIN at the same tide of the same day	0.8 mg L^-1, and 130% of the relevant control station's TIN at the same tide of the same day
BOD₅ in mg L^-1 (Depth-averaged^b)^c	1.9 mg L^-1, and 120% of the relevant control station's BOD5 at the same tide of the same day	2.8 mg L^-1, and 130% of the relevant control station's BOD5 at the same tide of the same day
TRC in mg L^-1 (Depth-averaged^b)^c	0.02 mg L^-1	0.02 mg L^-1

Parameters

Action Level

Limit Level

First-year Operation Phase Water Quality Monitoring

DO in mg L^{-1 a}

Surface and Middle

4.0 mg L^-1

Bottom

2.2 mg L^-1

Surface and Middle

3.0 mg L^-1

Bottom

1.5 mg L^-1

Water Temperature in °C

(Depth-averaged^b)^c

± 1.5 °C of baseline data, and

± 1.5 °C of the relevant control station's water temperature at the same tide of the same day

± 2.0 °C of baseline data, and

± 2.0 °C of the relevant control station's

water temperature at the same tide of

the same day

Turbidity in NTU

(Depth-averaged^b)^c

18.3 NTU, and

120% of the relevant control

station's turbidity at the same

tide of the same day

30.8 NTU, and

130% of the relevant control station's

turbidity at the same tide of the same

day

SS in mg L^-1

(Depth-averaged^b)^c

17.5 mg L^-1, and

120% of the relevant control

station's SS at the same tide of

the same day

29.5 mg L^-1, and

130% of the relevant control station's SS

at the same tide of the same day

TIN in mg L^-1

(Depth-averaged^b)^c

0.5 mg L^-1, and

120% of the relevant control

station's TIN at the same tide

of the same day

0.8 mg L^-1, and

130% of the relevant control station's

TIN at the same tide of the same day

BOD₅ in mg L^-1

(Depth-averaged^b)^c

1.9 mg L^-1, and

120% of the relevant control

station's BOD5 at the same tide

of the same day

2.8 mg L^-1, and

130% of the relevant control station's

BOD5 at the same tide of the same day

TRC in mg L^-1

(Depth-averaged^b)^c

0.02 mg L^-1

Notes:

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

b. “Depth-averaged” is calculated by taking the arithmetic means of reading of all three depths.

c. For water temperature, salinity, SS, turbidity, BOD₅, TIN and TRC, non-compliance of the water quality limits occurs when monitoring result is higher than the limits.

The Event and Action Plan for operation phase water quality monitoring is provided in Table 2.5.

Table 2.5 Event and Action Plan for Operation Phase Water Quality MonitorinG

Event	Action
Action Level being exceeded by one sampling day	1. Repeat in-situ measurement to confirm findings; 2. Check monitoring data, plant, equipment and Contractor(s)’s working methods; 3. Identify source(s) of impact and record in notification of exceedance; 4. Inform IEC, Contractor(s) and Project Proponents.	1. Check monitoring data submitted by ET and Contractor(s)’s working methods.	1. Confirm receipt of notification of exceedance in writing; 2. Check plant and equipment and rectify unacceptable practice.	1. Confirm receipt of notification of exceedance in writing.
Action Level being exceeded by two or more consecutive sampling days	1. Repeat in-situ measurement to confirm findings; 2. Check monitoring data, plant, equipment and Contractor(s)’s working methods; 3. Identify source(s) of impact and record in notification of exceedance; 4. Inform IEC, Contractor(s) and Project Proponents; 5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.	1. Check monitoring data submitted by ET and Contractor(s)’s working methods; 2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly; 3. Assess the effectiveness of the implemented mitigation measures.	1. Confirm receipt of notification of exceedance in writing; 2. Check plant and equipment and rectify unacceptable practice; 3. Consider changes of working methods; 4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days; 5. Implement the agreed mitigation measures.	1. Confirm receipt of notification of exceedance in writing; 2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented; 3. Ensure additional mitigation measures are properly implemented.
Limit Level being exceeded by one sampling day	1. Repeat in situ measurement to confirm findings; 2. Check monitoring data, plant, equipment and Contractor(s)’s working methods; 3. Identify source(s) of impact and record in notification of exceedance; 4. Inform IEC, Contractor(s), Project Proponents and EPD; 5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.	1. Check monitoring data submitted by ET and Contractor(s)’s working methods; 2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly; 3. Assess the effectiveness of the implemented mitigation measures.	1. Confirm receipt of notification of exceedance in writing; 2. Check plant and equipment and rectify unacceptable practice; 3. Critically review the need to change working methods; 4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days; 5. Implement the agreed mitigation measures.	1. Confirm receipt of notification of exceedance in writing; 2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented; 3. Ensure additional mitigation measures are properly implemented; 4. Request Contractor(s) to critically review the working methods.
Limit Level being exceeded by two or more consecutive sampling days	1. Repeat in situ measurement to confirm findings; 2. Check monitoring data, plant, equipment and Contractor(s)’s working methods; 3. Identify source(s) of impact and record in notification of exceedance; 4. Inform IEC, Contractor(s), Project Proponents and EPD; 5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.	1. Check monitoring data submitted by ET and Contractor(s)’s working methods; 2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly; 3. Assess the effectiveness of the implemented mitigation measures.	1. Confirm receipt of notification of exceedance in writing; 2. Check plant and equipment and rectify unacceptable practice; 3. Critically review the need to change working methods; 4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days; 5. Implement the agreed mitigation measures; 6. As directed by Project Proponents, slow down or stop all or part of the marine construction works until no exceedance of Limit Level.	1. Confirm receipt of notification of exceedance in writing; 2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented; 3. Ensure additional mitigation measures are properly implemented; 4. Request Contractor(s) to critically review the working methods; 5. Consider and instruct, if necessary, the Contractor(s) to slow down or to stop all or part of the marine construction works until no exceedance of Limit Level.

Event

Action

IEC

Contractor(s)

Project Proponents

Action Level being exceeded by one sampling day

1. Repeat in-situ measurement to confirm findings;

2. Check monitoring data, plant, equipment and Contractor(s)’s working methods;

3. Identify source(s) of impact and record in notification of exceedance;

4. Inform IEC, Contractor(s) and Project Proponents.

1. Check monitoring data submitted by ET and Contractor(s)’s working methods.

1. Confirm receipt of notification of exceedance in writing;

2. Check plant and equipment and rectify unacceptable practice.

1. Confirm receipt of notification of exceedance in writing.

Action Level being exceeded by two or more consecutive sampling days

1. Repeat in-situ measurement to confirm findings;

2. Check monitoring data, plant, equipment and Contractor(s)’s working methods;

3. Identify source(s) of impact and record in notification of exceedance;

4. Inform IEC, Contractor(s) and Project Proponents;

5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.

1. Check monitoring data submitted by ET and Contractor(s)’s working methods;

2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly;

3. Assess the effectiveness of the implemented mitigation measures.

1. Confirm receipt of notification of exceedance in writing;

2. Check plant and equipment and rectify unacceptable practice;

3. Consider changes of working methods;

4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days;

5. Implement the agreed mitigation measures.

1. Confirm receipt of notification of exceedance in writing;

2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented;

3. Ensure additional mitigation measures are properly implemented.

Limit Level being exceeded by one sampling day

1. Repeat in situ measurement to confirm findings;

2. Check monitoring data, plant, equipment and Contractor(s)’s working methods;

3. Identify source(s) of impact and record in notification of exceedance;

4. Inform IEC, Contractor(s), Project Proponents and EPD;

5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.

1. Check monitoring data submitted by ET and Contractor(s)’s working methods;

2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly;

3. Assess the effectiveness of the implemented mitigation measures.

1. Confirm receipt of notification of exceedance in writing;

2. Check plant and equipment and rectify unacceptable practice;

3. Critically review the need to change working methods;

4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days;

5. Implement the agreed mitigation measures.

1. Confirm receipt of notification of exceedance in writing;

2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented;

3. Ensure additional mitigation measures are properly implemented;

4. Request Contractor(s) to critically review the working methods.

Limit Level being exceeded by two or more consecutive sampling days

1. Repeat in situ measurement to confirm findings;

2. Check monitoring data, plant, equipment and Contractor(s)’s working methods;

3. Identify source(s) of impact and record in notification of exceedance;

4. Inform IEC, Contractor(s), Project Proponents and EPD;

5. Discuss with IEC and Contractor(s) on additional mitigation measures and ensure that they are implemented.

1. Check monitoring data submitted by ET and Contractor(s)’s working methods;

2. Discuss with ET and Contractor(s) on additional mitigation measures and advise Project Proponents accordingly;

3. Assess the effectiveness of the implemented mitigation measures.

1. Confirm receipt of notification of exceedance in writing;

2. Check plant and equipment and rectify unacceptable practice;

3. Critically review the need to change working methods;

4. Discuss with ET and IEC on additional mitigation measures and propose them to Project Proponents within 3 working days;

5. Implement the agreed mitigation measures;

6. As directed by Project Proponents, slow down or stop all or part of the marine construction works until no exceedance of Limit Level.

1. Confirm receipt of notification of exceedance in writing;

2. Discuss with the IEC on the proposed additional mitigation measures and agree on the mitigation measures to be implemented;

3. Ensure additional mitigation measures are properly implemented;

4. Request Contractor(s) to critically review the working methods;

5. Consider and instruct, if necessary, the Contractor(s) to slow down or to stop all or part of the marine construction works until no exceedance of Limit Level.

2.3 QA/QC Requirements

2.3.1 Caliberation of In-situ Instruments

In situ monitoring equipment for the measurement of DO, Temperature, Turbidity, pH and Salinity was checked, calibrated and certified by a laboratory accredited under HOKLAS before use, while the test kit for TRC was checked against the calibration check set provided by the manufacturer before commencement of monitoring. Copies of the calibration certificates for the measuring equipment for DO, Temperature, Turbidity, pH and Salinity are attached in Annex A. The in situ monitoring equipment for the measurement of DO, Temperature, Turbidity, pH and Salinity was subsequently re-calibrated every three months throughout the water quality monitoring. Responses of sensors and electrodes were checked with certified standard solutions before each use. Wet bulb calibrations for dissolved oxygen meter were carried out before commencement of monitoring and after completion of all measurements each day.

On-site calibration of field equipment followed 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 also made available to ensure monitoring could proceed uninterrupted even when equipment is under maintenance, calibration etc.

2.3.2 Decontamination Procedures

Water sampling equipment used during the course of the monitoring was decontaminated by manual washing and rinsed with clean seawater/distilled water after each sampling event. All disposable equipment was discarded after sampling.

2.3.3 Sampling Management and Supervision

All sampling bottles were labelled with the sample ID (including the indication of sampling station and tidal stage e.g. IM6_ME_S_R1), laboratory number and sampling date. All water samples were handled under chain of custody protocols and relinquished to the laboratory representatives at locations specified by the laboratory.

2.3.4 Quality Control Measures for Sample Testing

The sample testing was performed by ALS Technichem (HK) Pty Ltd. The following quality control programme was performed by the laboratory for every batch of 20 samples:

§ One method blank; and

§ One set of quality control (QC) samples (including method QC and sample duplicate).

2.4 Operation Phase Water Quality Monitoring Results

Operation phase water quality monitoring was conducted at three monitoring locations once per week for 13 sessions between 2 January and 28 March 2024. The detailed monitoring schedule is shown in Annex B. The monitoring results with weather and sea conditions at each monitoring day are shown in Annex C. Graphical presentation of water quality monitoring results is given in Annex D. During the monitoring sessions, the major activity on site was the operation of the LNG Terminal and no observable pollution source was recorded at the monitoring stations. No other external factors (e.g. surface runoff from nearby landmass, adverse weather) were identified that might affect water quality at the monitoring stations during the monitoring period.

An action Level exceedance was recorded for operation phase water quality monitoring in the reporting period. Investigation on the exceedances was conducted and summarised in Table 2.6.

Table 2.6 Details of exceedances for operational phase water quality monitoring

Date	Tide	Parameter	Monitoring Station	Level of Exceedance	Investigation
23 February 2024	Mid-ebb	Depth- Average 5-day biochemical oxygen demand (BOD5)	IM6	Action	Discharge of cooled seawater for the operation of the regasification system was undertaken on 23 February 2024. According to the information provided by HKLTL and the operator, the flow rate of the cooled seawater discharge was about 5,000 m³/hr. In addition, there was effluent discharge from the sewage treatment plant with a flow rate less than 10 m³/day. Discharge of seawater for the maintenance of firewater operation system was undertaken on 23 February 2024. According to the information provided by HKLTL and the operator, the flow rate of the seawater discharge was about 15 m³/hr. The exceedance in 5-day biochemical oxygen demand (BOD5) is unlikely due to the operation of the Project, in view of the following: § The seawater and effluent discharge complied with the requirements as stated in the licence under the Water Pollution Control Ordinance. § With reference to the marine water quality data recorded by EPD since 1989 at the station located closest to the Project (i.e. SM17), fluctuations of BOD5 were recorded with ranges between <0.1 mg/L and 7.3mg/L. The current measured level is within the ranges of the historical dataset and thus considered to be sporadic event and characteristics of water quality in this area of Hong Kong.

Date

Tide

Parameter

Monitoring Station

Level of Exceedance

Investigation

23 February 2024

Mid-ebb

Depth-

Average

5-day

biochemical

oxygen

demand (BOD5)

IM6

Action

Discharge of cooled seawater

for the operation of the

regasification system

was undertaken on 23 February

2024. According to the

information provided by HKLTL and the operator, the flow rate of the cooled seawater discharge was about 5,000 m³/hr. In addition, there was effluent discharge from the sewage treatment plant with a flow rate less than 10 m³/day.

Discharge of seawater for the

maintenance of firewater

operation system was

undertaken on 23 February

2024. According to the

information provided by HKLTL and the operator, the flow rate of the seawater discharge was

about 15 m³/hr.

The exceedance in 5-day biochemical oxygen demand (BOD5) is unlikely due to the operation of the Project, in view of the following:

§ The seawater and effluent discharge complied with the requirements as stated in the licence under the Water Pollution Control Ordinance.

§ With reference to the marine water quality data recorded by EPD since 1989 at the station located closest to the Project (i.e. SM17), fluctuations of BOD5 were recorded with ranges between <0.1 mg/L and 7.3mg/L. The current measured level is within the ranges of the historical dataset and thus considered to be sporadic event and characteristics of water quality in this area of Hong Kong.

Based on the investigation results above, the exceedance was not Project-related. Nevertheless, HKLTL and the operator were reminded to ensure mitigation measures for water quality impacts as set out in the Updated EM&A Manual are fully and properly implemented. In addition, the discharge of effluent shall follow the requirements as stated in the licence under the Water Pollution Control Ordinance.

Overall, deterioration of water quality and indirect impacts at water and ecological sensitive receivers were not detected. The operation of the Project did not result in unacceptable water quality impacts to the nearby water and ecological sensitive receivers, which aligns with the EIA study predictions.

2.5 Summary of Exceedances of the Environmental Quality Performance Limit

There were no Project related Action and Limit Level exceedances for operation phase water quality monitoring in the reporting period.

2.6 Summary of Environmental Complaints, Notification of Summons and Successful Prosecution

There were no environmental complaints, notification of summons and successful prosecutions recorded for the operation of the Project in the reporting period.

3. Conculsion

This is the quarterly report for the operation phase water quality monitoring for the LNG Terminal which summarises the key monitoring results for the reporting period of January to March 2024 in accordance with the Updated EM&A Manual of the Project.

Operation phase water quality monitoring was conducted at three monitoring locations once per week for 13 sessions between 2 January and 28 March 2024. There were no Project related Action and Limit Level exceedances for operation phase water quality monitoring in the reporting period. Overall, deterioration of water quality and indirect impacts at water and ecological sensitive receivers were not detected. The operation of the Project did not result in unacceptable water quality impacts to the nearby water and ecological sensitive receivers, which aligns with the EIA study predictions.

There were no environmental complaints, notification of summons and successful prosecutions recorded for the operation of the Project in the reporting period.

([1]) Application for variation of an environmental permit for FEP-01/558/2018 was undertaken and the latest FEP (FEP-01/558/2018/A) was issued on 6 November 2020.

([2]) Application for variation of an environmental permit for FEP-03/558/2018/A was undertaken and the latest FEP (FEP-03/558/2018/B) was issued on 25 August 2021.

([3]) Application for variation of an environmental permit for FEP-02/558/2018 was undertaken and the latest FEP (FEP-02/558/2018/A) was issued on 22 December 2020.