The construction works of the Airport Tung Chung Link (“ATCL”) Project commenced on 17 December 2025; therefore, the construction phase EM&A programme of the ATCL Project started on 17 December 2025. This is the 5^th Monthly EM&A report summarising the key findings of the construction phase EM&A programme from 1 to 30 April 2026 (the reporting period) and is submitted to fulfil requirements in Condition 3.4 of EP and Section 12.3 of EM&A Manual of the Project.

The ET of the ATCL Project has undertaken environmental site inspections and environmental monitoring under the construction phase EM&A programme during the reporting period. The marine construction works of the marine viaduct between the Airport Island and Tung Chung was commenced on 31 March 2026; therefore, the impact water quality monitoring for the marine viaduct started on 31 March 2026.

Table I: Summary of Monitoring Activities in the Reporting Period

Monitoring Activities	Date of Monitoring Events	Number of Monitoring Events
Air Quality Monitoring	2, 8, 14, 20, 24 and 30 Apr 2026	6
Noise Monitoring	1, 9, 16, 21 and 28 Apr 2026	5
Water Quality Monitoring	2, 9, 11, 14, 16, 18, 21, 23, 25, 28 and 30 Apr 2026	11

Breaches of Action and Limit Levels

Air quality, noise and water quality monitoring was conducted during the reporting period, and no exceedance for air quality and noise was recorded.

For water quality, the dissolved oxygen (DO) and suspended solids (SS) monitoring results at all monitoring stations were within the corresponding Action and Limit Levels in the reporting period. One turbidity monitoring result on 2 April 2026 triggered the Action Level. After investigation, it was concluded that the exceedance was not related to the Project.

Site Inspection

During the reporting period, four (4) regular weekly site inspections were carried out on 8, 13, 20 and 27 April 2026. A joint IEC site inspection with Environmental Management Meeting was carried out on 20 April 2026. Also, a joint site inspection with EPD, AAHK and IEC was carried out on 24 April 2026.

Complaint Log

There was no complaint received in relation to the environmental impact during the reporting period.

Notifications of Summons and Successful Prosecutions

There was no notification of summons or successful prosecutions received during the reporting period.

Reporting Changes

There was no reporting change during the reporting period.

Key Activities in the Reporting Period

As informed by the Contractor, the major construction activities for the reporting period are summarised below:

Land-based portion

· Pre-drilling (site preparation works);

· Site clearance (site preparation works);

· Piling works;

· Underground utilities (UU) diversion works;

· Hoarding modification works;

· Seawall excavation; and

· UU protection works.

Marine-based portion

· Pre-drilling (site preparation works); and

· Silt curtain and temporary working platform installation.

Future Key Issues

As informed by the Contractor, the major construction activities for the next reporting period are summarised below:

Land-based portion

· Pre-drilling (site preparation works);

· Site clearance (site preparation works);

· Piling works;

· UU diversion works;

· Sheet piling works;

· Hoarding modification works;

· Fixed networks operators (FNO) protection;

· Seawall excavation; and

· UU protection works.

Marine-based portion

· Pre-drilling (site preparation works); and

· Silt curtain and temporary working platform installation.

1 Introduction

1.1 Background

The project proponent, Airport Authority Hong Kong (“AAHK”) is planning to construct a dedicated road, named as the Airport Tung Chung Link (“ATCL”), to extend the passenger transport services using autonomous vehicles (“AV”) from the Airportcity Link (“ACL”), which is currently under construction, to Tung Chung, aiming to enhance connectivity between the Hong Kong Port (“HKP”), SKYCITY and Tung Chung.

ATCL Project (hereafter referred to as “the Project”), comprising ATCL and the marine facilities in the waters between Airport Island and HKP Island, is a designated project under Environmental Impact Assessment Ordinance (“EIAO”). The ATCL Project Environmental Impact Assessment Report (“EIAR”) (Register No. AEIAR-254/2023) was approved by the Director of Environmental Protection (“DEP”) and an Environmental Permit No. EP-630/2023 for the construction and operation of the ATCL Project was first granted by DEP to AAHK on 26 October 2023. Subsequently an application for variation of the Environmental Permit was submitted on 3 November 2025 and the current valid Environmental Permit (No. EP-630/2023/A) (hereafter referred to as “the EP”) was issued by Environmental Protection Department (“EPD”) on 1 December 2025.

The marine facilities in the waters between Airport Island and HKP Island are included in the ATCL Project EIAR (Register No. AEIAR-254/2023) and the ATCL Project EP (EP No. EP-630/2023/A), however, the construction of marine facilities and spur line of ATCL (including Academy Station) are not included in the current stage of ATCL construction. The alignment of ATCL is shown in Figure 1.1.

In February 2025, Mott MacDonald Hong Kong Limited (MMHK) was commissioned by AAHK under Contract C24C02 to provide Environmental Team (ET) consultancy services for implementation of an EM&A programme in accordance with the ATCL Project EP requirements throughout the Pre-construction, Construction and Post-construction phases of the ATCL Project. The construction phase EM&A programme of the ATCL Project started on 17 December 2025.

This is the 5^th Monthly EM&A report summarising the key findings of the construction phase EM&A programme from 1 to 30 April 2026 (the reporting period) and is submitted to fulfil requirements in Condition 3.4 of EP and Section 12.3 of EM&A Manual of the Project.

1.2 Project Organisation

The organisation chart and lines of communication with respect to the on-site environmental management structure of the key personnel are shown in Appendix A. The key personnel contact names and numbers are summarized in Table 1.1.

Table 1.1: Contact Information of Key Personnel

Party	Position	Name	Telephone
Project Manager’s Representative (Airport Authority Hong Kong)	Principal Manager, Environmental Compliance, Sustainability	Lawrence Tsui	2183 2734
Environmental Team (ET) (Mott MacDonald Hong Kong Limited)	Environmental Team Leader	Thomas Chan	2828 5967
Environmental Team (ET) (Mott MacDonald Hong Kong Limited)	Deputy Environmental Team Leader	Ken Wong	2828 5817
Independent Environmental Checker (IEC) (AECOM Asia Company Limited)	Independent Environmental Checker	Lemon Lam	3856 5680
Main Contractor of Contract No. C24W08 (Penta-Ocean Construction Co. Ltd.)	Project Manager	Hiroshi Fujimoto	9165 4070
	Environmental Manager	Gideon Cheng	9731 5852
	Environmental Officer	C.H. So	9139 3831
	Environmental Officer	Iris Ho	6469 3189

1.3 Construction Programme

The construction phase EM&A programme of the Project started on 17 December 2025, while marine construction works of the marine viaduct between the Airport Island and Tung Chung was commenced on 31 March 2026.

The construction works programme and the construction works area of the Project are shown in Appendix B and Figure 1.1 respectively.

1.4 Construction Works Undertaken During the Reporting Month

A summary of construction activities undertaken during this reporting period is presented in Figure 1.2 and summarised below:

Land-based portion

· Pre-drilling (site preparation works);

· Site clearance (site preparation works);

· Piling works;

· UU diversion works;

· Hoarding modification works;

· Seawall excavation; and

· UU protection works.

Marine-based portion

· Pre-drilling (site preparation works); and

· Silt curtain and temporary working platform installation.

1.5 Schedule and Progress of EP Submission

The status of the submissions as required in the EP is presented in Table 1.2.

Table 1.2: Status of the Submissions as Required under the EP

EP Condition	Submission	Submission Timeframe	Status
2.8	EP Submission Schedule	No later than 1 month before the commencement of construction of the Project	Submitted and accepted by the EPD
2.9	Management Organization	No later than 2 weeks before the commencement of construction of the Project	Submitted and accepted by the EPD, updated version submitted
2.10	Construction Works Schedule and Location Plans	No later than 2 months before the commencement of construction of the Project	Submitted and accepted by the EPD
2.11	Construction Noise Management Plan	No later than 2 months before the commencement of construction works of the Project	Submitted and accepted by the EPD, updated version submitted
2.13	Silt Curtain Deployment Plan	No later than 2 months before the commencement of marine works involving deployment of silt curtains of the Project	Submitted and accepted by the EPD
2.14	Landscape and Visual Mitigation Plan	No later than 2 months before the commencement of construction of the Project or otherwise approved by the Director	Submitted
2.17	Noise Performance Test Report for Zero Emission Vehicles	At least 2 months before commencement of operation of the Project	--
3.3	Baseline Monitoring Report	At least 2 weeks before the commencement of construction of the Project	Submitted and accepted by the EPD

2 Air Quality

2.1 Monitoring Requirements

According to the Sections 3.2.23 to 3.2.28 in the ATCL Project EM&A Manual, impact air quality monitoring for 1-hour Total Suspended Particulates (TSP) should be carried out at designated monitoring locations for at least three times in every six days when the highest dust impacts occur. Further details of the impact air quality monitoring are presented in the following sections.

2.1.1 Monitoring Parameters

1-hour TSP levels have been measured during impact air quality monitoring in accordance with the ATCL Project EM&A Manual. The monitoring information (e.g. monitoring date, monitoring time, weather conditions, dust source(s), other specific phenomena) was recorded in the data record sheet during the monitoring.

2.1.2 Monitoring Locations

The monitoring locations for impact air quality monitoring are summarised in Table 2.1 and shown in Figure 2.1.

Table 2.1: Impact Air Quality Monitoring Stations

ID	ASR ID adopted in EIA Report	Description	Monitoring Parameter	Monitoring Level
AM1a ^[1]	---	Tat Tung Road Garden	1-hour TSP	Ground Floor
AM2	A11	Hong Kong Airlines Training Academy	1-hour TSP	Ground Floor
AM3	A10	CNAC House	1-hour TSP	Podium

Remark:

[1] As advised by the Leisure and Cultural Services Department, Tung Chung Community Garden (original monitoring station ID: AM1; ASR ID: A20) as stipulated in Table 3.1 of the ATCL Project EM&A Manual has been decommissioned and hence not accessible. Therefore, Tat Tung Road Garden which located next to the Tung Chung Community Garden is proposed to be the alternative air quality monitoring station. The proposed alternative location was agreed by the Independent Environmental Checker (“IEC”) and AAHK on 3 April 2025 and approved by EPD on 2 June 2025.

Impact air quality monitoring station, AM4, which is designated in the ATCL Project EM&A Manual for the proposed marine facilities during construction phase is not included in this report, as the construction of marine facilities is not part of the current stage of ATCL construction (refer to Section 1.1).

2.1.3 Monitoring Equipment and Methodology

Direct reading method by the use of portable direct reading dust meters was proposed to be used for impact air quality monitoring for this ATCL Project, based on the provisions set out in Section 3.2.7 of the ATCL Project EM&A Manual. With the use of portable direct reading dust meters, it can allow prompt and direct results for the EM&A reporting and the implementation of the Event and Action Plan. The proposal for adopting direct reading method by the use of portable direct reading dust meters was approved by the IEC.

General meteorological conditions throughout the impact monitoring period were recorded. It is considered that the wind data obtained at the existing Hong Kong Observatory’s (HKO) Chek Lap Kok wind station is representative of the Project area and could be used for undertaking the impact air quality monitoring programme for the ATCL Project. The proposed use of the existing wind data collected from Chek Lap Kok wind station for wind data collection instead of setting up wind monitoring equipment near the monitoring stations was proposed by the ET Leader and agreed by the IEC, in accordance with the requirements stated in Section 3.2.9 of the ATCL Project EM&A Manual.

The measuring procedures of the portable direct reading dust meter are followed in accordance with the Manufacturer’s Instruction Manual as presented below:

SIBATA model no. LD-3B

a) set POWER to “ON” and make sure that the battery level was not flash or in low level;

b) pull the air sampling inlet cover up;

c) push the knob at [MEASURE] position;

d) set time/mode setting to [BG] by pushing the time setting switch;

e) start the background measurement by pushing the Start/Stop switch once;

f) turn knob to [SENSI. ADJ] position and push Start/Stop switch once to start the span check;

g) gently return knob to the [MEASURE] position;

h) push the time setting switch to change the time setting display to [LOG];

i) remove the cap and start measurement.

SIBATA model no. LD-5R

a) turn ON the power switch;

b) close the air sampling port cap;

c) turn the scattering plate knob to [MEASURE];

d) perform the BG measurement (8 seconds + 6 seconds);

e) turn the scattering plate knob to [SENSI. ADJ.];

f) perform the SPAN measurement (60 seconds);

g) turn the scattering plate knob to [MEASURE];

h) open the air sampling port cap;

i) select the measurement mode;

j) start the measurement;

k) finish the measurement (automatically or manually);

l) close the air sampling port cap;

m) perform the BG measurement (8 seconds + 6 seconds);

n) turn OFF the power switch

Table 2.2 summarises the equipment used in the reporting period. Copies of the calibration certificates for the equipment used during the reporting period are attached in Appendix D. The portable direct reading dust meter would be calibrated every year against High Volume Sampler (HVS) to check the validity and accuracy of the results measured by direct reading method.

Table 2.2: Equipment Used for Impact Air Quality Monitoring in the Reporting Period

Equipment	Model
Portable Direct Reading Dust Meter	SIBATA LD-3B (serial no. 456668)
SIBATA LD-3B (serial no. 6z7780)

Equipment

Model

Portable Direct Reading Dust Meter

SIBATA LD-3B (serial no. 456668)

SIBATA LD-3B (serial no. 6z7780)

2.1.4 Action and Limit Levels

In accordance with the ATCL Project EM&A Manual, baseline air quality monitoring of 1-hour TSP levels at the air quality monitoring stations were established as presented in the Baseline Monitoring Report. The Action and Limit Levels of the impact air quality monitoring are presented in Table 2.3.

Table 2.3: Action and Limit Levels for Air Quality

Parameter	Monitoring Station	Action Level (μg/m³)	Limit Level (μg/m³)
1-hour TSP Level in μg/m³	AM1a	270	500
	AM2	274	500
	AM3	275	500

2.1.5 Event and Action Plan

In the event of monitoring results at air quality monitoring stations exceeding the Action and/or Limit levels for air quality as defined in Table 2.3, actions in accordance with the Event and Action Plan in Appendix E shall be carried out.

2.2 Monitoring Schedule and Summary of Impact Air Quality Monitoring Results

Impact air quality monitoring was conducted on 2, 8, 14, 20, 24 and 30 April 2026 during the reporting period. The schedule of impact air quality monitoring conducted in the reporting period is provided in Appendix F. The impact air quality monitoring results obtained in the reporting period are summarised in Table 2.4, with detailed impact air quality monitoring results, graphical presentation and wind data presented in Appendix C.

Table 2.4: Summary of Impact Air Quality Monitoring Results

Monitoring Station	1-hr TSP Concentration Range (μg/m³)	Average 1-hr TSP Concentration (μg/m³)	Action Level (μg/m³)	Limit Level (μg/m³)
AM1a	35 - 51	43	270	500
AM2	42 - 57	50	274	500
AM3	41 - 55	47	275	500

During the monitoring, no specific observation was noted in the vicinity.

The monitoring results were within the corresponding Action and Limit Levels at all monitoring stations in the reporting period and no exceedance for impact air quality monitoring was recorded.

3 Noise

3.1 Monitoring Requirements

According to the Section 4.3.11 in the ATCL Project EM&A Manual, impact construction noise monitoring for L_eq_(30min)should be carried out at designated monitoring locations once every week when there are project-related construction activities being undertaken within a radius of 300m from the monitoring stations. Further details of the impact construction noise monitoring are presented in the following sections.

3.1.1 Monitoring Parameters

Construction noise level should be measured in terms of the A-weighted equivalent continuous sound pressure level (L_eq). L_eq_(30min)shall be used as the monitoring parameter for the time period between 0700 and 1900 hours on normal weekdays. For all other time periods, L_eq_(5min)shall be employed for comparison with the Noise Control Ordinance (NCO) criteria. As supplementary information for data auditing, statistical results such as L₁₀ and L₉₀ were also obtained for reference.

3.1.2 Monitoring Locations

The monitoring locations for impact construction noise monitoring are summarised in Table 3.1 and shown in Figure 3.1.

Table 3.1: Noise Monitoring Stations

Monitoring Station ID	Representative NSR ID in EIA Report	Description	Monitoring Level	Type of Measurement
NM1	N01	Seaview Crescent	Roof-top of Block 1 (Direction: SW)	Façade measurement
NM2	N03	Ling Liang Church E Wun Secondary School	Roof-top (Direction: W)	Façade measurement
NM3	N08	Fu Tung Estate Tung Ma House	Roof-top (Direction: N)	Façade measurement
NM4	N09	Tung Chung Crescent	Roof-top of Block 5 (Direction: NE)	Façade measurement
NM5 ^[1]	N10	Priests’ Quarters of the Planned Visitation Church Development	--	--

Remark:

[1] The Priests’ Quarters of the Planned Visitation Church Development is under construction during the impact noise monitoring period. Subject to the construction programme of the planned NSR, its impact monitoring status will be reviewed when necessary.

3.1.3 Monitoring Equipment and Methodology

Hand-held sound level meter was used for impact noise monitoring. Sound level meter in compliance with the International Electrotechnical Commission Publications 651:1979 (Type 1) and 804:1985 (Type 1) specifications was used for carrying out the impact construction noise monitoring. Immediately prior to and following each noise measurement, the accuracy of the sound level meter was checked using an acoustic calibrator generating a known sound pressure level at a known frequency. The noise measurements were made in accordance with standard acoustical principles and practices in relation to weather conditions. Measurements would be accepted as valid only if the calibration level from before and after the noise measurement agrees to within 1.0 dB.

Table 3.2 summarises the equipment used in the reporting period. Copies of the calibration certificates for the equipment used during the reporting period are attached in Appendix D.

Table 3.2: Equipment Used for Impact Construction Noise Monitoring in the Reporting Period

Equipment	Model
Sound Level Meter	Rion NL-53 (serial no. 01141565)
Acoustic Calibrator	CAL 200 (serial no.: 10227)

3.1.4 Action and Limit Levels

The Action and Limit Levels of the impact noise monitoring are presented in Table 3.3.

Table 3.3: Action and Limit Levels for Construction Noise

Monitoring Station	Time Period	Action Level	Limit Level (L_eq_(30min),dB(A))
NM1	0700-1900 hrs on normal weekdays	When one documented complaint is received	75
NM2			70 dB(A) and 65 dB(A) during examination period
NM3			75
NM4			75
NM5			75

3.1.5 Event and Action Plan

In the event of monitoring results at construction noise monitoring stations exceeding the Action and/or Limit levels for construction noise as defined in Table 3.3, actions in accordance with the Event and Action Plan in Appendix E shall be carried out.

3.2 Monitoring Schedule and Summary of Impact Construction Noise Monitoring Results

Impact construction noise monitoring was conducted on 1, 9, 16, 21 and 28 April 2026 during the reporting period. The schedule of impact construction noise monitoring conducted in the reporting period is provided in Appendix F. The impact noise monitoring results obtained in the reporting period are summarised in Table 3.4, with detailed impact noise monitoring results and graphical presentation presented in Appendix C.

Table 3.4: Summary of Impact Noise Monitoring Results

Monitoring Station	Noise Level Range (L_eq_(30min),dB(A))	Limit Level (L_eq_(30min),dB(A))
NM1 ^[2]	52 - 65	75
NM2	63 - 64	65 / 70 ^[1]
NM3	64 - 65	75
NM4	62 - 63	75

Notes:

[1] Will be reduced to 65dB(A) during school examination periods. School examination took place from 28 to 29 April 2026 during this reporting period.

[2] When the noise measurement results being higher than the baseline monitoring levels, to reduce the influence of non-Project related noise on the monitoring results, those measurement results would be corrected with reference to the baseline monitoring results.

During the monitoring, traffic noise was noted in the vicinity.

No complaint was received from any sensitive receiver that triggered the Action Level. All monitoring results were also within the corresponding Limit Levels at all monitoring stations in the reporting period. Therefore, no exceedance for impact construction noise monitoring was recorded during the reporting period.

4 Water Quality

4.1 Monitoring Requirements

According to the Sections 5.7.7 to 5.7.11 in the ATCL Project EM&A Manual, impact water quality monitoring should be carried out at designated monitoring locations for three days per week, at mid-flood and mid-ebb tides, during the marine construction period. Further details of the impact water quality monitoring are presented in the following sections.

4.1.1 Monitoring Parameters

Monitoring for dissolved oxygen (DO), dissolved oxygen saturation (DO%), temperature, pH, turbidity, salinity, suspended solid (SS) and water depth should be undertaken at all designated monitoring locations. All parameters should be measured in-situ whereas SS should be determined by an accredited laboratory. DO should be presented in mg/L and in % saturation.

Two replicate in-situ measurements and samples collected from each independent sampling event shall be collected to ensure a robust statistically interpretable database.

Other relevant data should also be recorded, including monitoring location / position, time, water depth, tidal stages, weather conditions and any special phenomena or work underway at the construction site.

4.1.2 Monitoring Locations

The marine facilities in the waters between Airport Island and HKP Island are included in the approved ATCL Project EIAR and the ATCL Project EP, however, the construction of marine facilities is not included in the current stage of ATCL construction. Therefore, water quality monitoring will only be undertaken for the marine water quality monitoring stations for the marine viaduct between the Airport Island and Tung Chung (namely IM2, IM3, SR3, C3 and C4).

The monitoring locations for impact water quality monitoring are summarised in Table 4.1 and shown in Figure 4.1.

Table 4.1: Water Quality Monitoring Stations

Stations	Descriptions	Easting	Northing
IM2	Impact Station	812258	817871
IM3	Impact Station	810725	816626
SR3	Seawater Intake at Tung Chung	811780	817172
C3	Control Station	812785	818754
C4	Control Station	809533	817234

4.1.3 Monitoring Equipment and Methodology

Monitoring Methodology

Measurement was taken at 3 water depths, namely, 1m below water surface, mid-depth and 1m above sea bed, except where the water depth less that 6m, the mid-depth station was omitted; where the water depth less than 3m, only the mid-depth station was monitored.

Duplicate in-situ measurements and water samples collected from each independent monitoring event was conducted for all parameters to ensure a robust statistically interpretable dataset. At each measurement depth, two consecutive measurements were taken. The probes were retrieved out of the water after the first measurement and then redeployed for the second measurement. The reading would have been discarded and further readings would have been taken when more than 25% difference in value between the first and second measurement of on-site parameters being identified.

In addition, no sampling would have been carried out, when typhoon signal No. 3 or above or black rainstorm signal being hoisted.

Monitoring Equipment

In-situ measurements at monitoring locations including dissolved oxygen (DO), dissolved oxygen saturation (DO%), pH, temperature, turbidity, salinity and water depth were collected using the equipment listed in Table 4.2.

Table 4.2: Equipment Used for Impact Water Quality Monitoring in the Reporting Period

Equipment	Model
Monitoring Position Equipment	XINUO XF-1069B
Water Sampler	Horizontal Alpha™ Bottles
Water Depth Detector	LUCKY™ FF718Li
Multifunctional Meter (measurement of DO, DO% temperature, turbidity, salinity and pH)	YSI ProDSS (serial no. 16H104233 and 24A102447)

Calibration of In-situ Instruments

In-situ monitoring instruments for water quality parameters were checked, calibrated and certified by a laboratory accredited under HOKLAS before use. Responses of sensors and electrodes were checked with certified standard solutions before each use.

Wet bulb calibration for DO measurement was carried out before commencement of monitoring and after completion of all measurements each day. The turbidity meter was calibrated in order to establish the relationship between Nephelometric Turbidity Unit (NTU) and the levels of suspended solids. A zero check in distilled water was performed with the turbidity probe at least once per monitoring day. The probe was then calibrated with a solution of known NTU. Standard buffer solutions of at least pH 7 and pH 10 was used for calibration of the pH instrument before and after use on each monitoring day.

Copies of the calibration certificates of the monitoring equipment used in the reporting period are attached in Appendix D.

Sample Containers and Storage

Water samples for SS determination were be stored in high density polythene containers with no preservative added, packed in ice (cooled to 4^oC without being frozen) and delivered to the testing laboratory within 24 hours of collection and analysed as soon as possible after collection.

Laboratory Measurement / Analysis

Analysis of SS level was carried out by ALS Technichem Hong Kong Limited, a HOKLAS accredited laboratory (Reg. No. 066). Sufficient water samples were collected at the monitoring stations for carrying out the laboratory SS determination. All samples were assigned a unique code and accompanied by Chain of Custody (COC) sheets.

The SS determination work started within 24 hours after collection of the water samples. The SS analyses followed the standard method APHA 2540D with a detection limit of 1 mg/L as described in APHA Standard Methods for the Examination of Water and Wastewater, 21st Edition.

4.1.4 Action and Limit Levels

In accordance with the ATCL Project EM&A Manual, baseline water quality monitoring at the water quality monitoring stations were established as presented in the Baseline Monitoring Report. The Action and Limit Levels of the impact water quality monitoring are presented in Table 4.3.

Table 4.3: Action and Limit Levels for Water Quality

Parameters	Action Level	Limit Level
DO in mg/L	Surface and Middle 5.1 Bottom 3.5	Surface and Middle 4.0 Bottom 2.0
SS in mg/L	Depth Average 10.8 and 120% of upstream control station at the same tide of the same day	Depth Average 13.4 and 130% of upstream control station at the same tide of the same day
Turbidity in NTU	Depth Average 7.9 and 120% of upstream control station at the same tide of the same day	Depth Average 9.9 and 130% of upstream control station at the same tide of the same day

Notes:

1. "Depth Average" is calculated by taking the arithmetic means of reading of all sampling depths.

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

3. For turbidity and SS, non-compliance of the water quality limits occurs when monitoring result is higher than the limits.

4. All the figures given in the table are used for reference only and the EPD may amend the figures whenever it is considered as necessary.

As learnt from the dominant flow direction, control station C4 is at the upstream during ebb tide while control station C3 is at the upstream during flood tide. As such, control station C4 is assigned as the control station during the ebb tide while control station C3 is assigned as the control station during the flood tide. The arrangement during the impact monitoring is detailed in Table 4.4.

Table 4.4: Corresponding Control and Impact Monitoring Stations during Impact Monitoring

Tidal Direction	Control Station	Impact Stations
Ebb Tide	C4	IM2, IM3, SR3
Flood Tide	C3	IM2, IM3, SR3

4.1.5 Event and Action Plan

In the event of water quality monitoring results at impact and seawater intake stations exceeding the Action and/or Limit levels for water quality as defined in Table 4.3, actions in accordance with the Event and Action Plan in Appendix E shall be carried out.

4.2 Monitoring Schedule and Summary of Impact Water Quality Monitoring Results

The marine construction works of the marine viaduct commenced on 31 March 2026. The impact water quality monitoring of the marine viaduct was conducted on 2, 9, 11, 14, 16, 18, 21, 23, 25, 28 and 30 April 2026 during the reporting period. The schedule of impact water quality monitoring conducted in the reporting period is provided in Appendix F. The detailed impact water quality monitoring results and graphical presentation presented in Appendix C.

The DO and SS monitoring results at all monitoring stations were within the corresponding Action and Limit Levels in the reporting period. One turbidity monitoring result on 2 April 2026 triggered the Action Level. Table 4.5 presents the summary of exceedance for impact water quality during the reporting period.

Table 4.5: Summary of Impact Water Quality Exceedances

Date	Parameter	Impact Station	Tide	Sampling Depth	Level of Exceedance
2 Apr 2026	Turbidity	IM3	Mid-Flood	Depth Average	Action Level

4.2.1 Investigation of Exceedance

According to the Contractor’s information, supporting casing installation of temporary working platform for Pier 10 was commenced at 13:00 on 2 April 2026, which was after the mid-flood tide monitoring at IM3 conducted at 07:13. No marine construction activities were carried out at other piers on 2 April 2026 according to Contractor’s record.

Silt curtain deployment and daily visual inspection for silt curtains were implemented by the Contractor. As recorded in the daily visual inspection checklist for silt curtain dated 2 April 2026, no unsatisfactory findings were identified during the inspection.

According to the on-site observation by the monitoring team and information from the Contractor, no discharge and spillage incidents were recorded on 2 April 2026. During the mid flood-tide monitoring event, no sediment plume, muddy conditions nor abnormal conditions were observed by the monitoring team in the vicinity. During the weekly site inspections conducted by the ET before the monitoring day (i.e. 31 Mar 2026) and after the monitoring day (i.e. 8 Apr 2026), no water quality-related observation was logged at the concerned location.

Moreover, no water quality exceedance of turbidity was found during mid ebb-tide on the same day (which was conducted later on that day) for the same construction activities. Also, SR3 is located in the close proximity to the active marine works area (i.e. Pier 10), while no exceedance of turbidity was recorded at SR3.

Based on the above finding, it was concluded that the exceedance was not related to the Project. The Contractor will keep implement, monitor and maintain all mitigation measures outlined in the EIA, EM&A Manual and the Silt Curtain Deployment Plan, to ensure that water quality impacts are minimized.

5 Environmental Site Inspection and Audit

5.1 Environmental Site Inspection

Site inspections were carried out by ET on a weekly basis to monitor the implementation of proper environmental pollution control mitigation measures for the Project. Key observations were recorded in the site inspection checklist and passed to the Contractor together with the appropriate recommended mitigation measures where necessary.

During the reporting period, regular weekly site inspections were carried out on 8, 13, 20 and 27 April 2026. A joint IEC site inspection with Environmental Management Meeting was carried out on 20 April 2026. Also, a joint site inspection with EPD, AAHK and IEC was carried out on 24 April 2026. Bi-weekly landscape and visual site audit was carried out on 13 and 27 April 2026. The site inspection schedule is provided in Appendix F.

Key observations and reminders during the site inspections and landscape and visual site audit are described in Table 5.1.

Table 5.1: Summary of Site Inspections and Recommendations

Inspection Date	Key Observations / Reminders	Recommendations / Actions	Close-Out Date
12 Feb 2026	At Pier 12, machines not specified in the CNMP were found idle on site.	On-going	--
12 Feb 2026	At Pier 12, 1 crawler crane is on-site and operating, and no QPME label being presented.	On-going	--
12 Feb 2026	At Pier 12, the contractor should enhance the setup of noise barrier for the excavator.	On-going	--
27 Mar 2026	At Seawall Modification Area, dust nuisance was observed on the barge.	Water spraying was provided to the stockpile for the loading and unloading works.	8 Apr 2026
31 Mar 2026	At Pier 12, stockpile was exposed.	Stockpile was removed.	8 Apr 2026
8 Apr 2026	At Viaduct 3, untreated effluent was observed at the drainage.	Drainage was cleared.	13 Apr 2026
8 Apr 2026	At Pier 12 and Viaduct 3, stagnant water was stored inside the drip tray.	Stagnant water was cleared.	13 Apr 2026
13 Apr 2026	At TCCS, oil stain was observed beside the generator.	Oil stain has been cleared.	20 Apr 2026
13 Apr 2026	At TCCS, construction materials were found covering the existing drainage.	Drainage has been cleaned up.	20 Apr 2026
13 Apr 2026	At Pier 12, NRMM label was missing on the air compressor.	NRMM label has been affixed on the air compressor.	20 Apr 2026
20 Apr 2026	At TCCS, fugitive dust was observed at construction works area and debris was found near public road.	Water spraying was provided and dusty material was cleared.	27 Apr 2026
20 Apr 2026	At TCCS, chemicals were found unattended without any spillage preventive measures.	Chemical container was cleared.	27 Apr 2026
20 Apr 2026	At Pier 12, a large portion of the stockpiles were exposed.	Stockpile was covered with impervious material.	27 Apr 2026
20 Apr 2026	At Pier 7, NRMM and QPME labels were not presented on the crawler crane.	On-going	--
20 Apr 2026	At Pier 7, the sound power levels of 2 generators did not tally with those recommended in the CNMP.	On-going	--
27 Apr 2026	At Viaduct 1, stockpiles were found exposed.	On-going	--
27 Apr 2026	At the seawall modification works, the slope surface with cement was exposed.	On-going	--
27 Apr 2026	At Pier 6, mud trails were observed at the site exit.	On-going	--

5.2 Waste Management

In accordance with Condition 2.16 of the EP, all dump trucks for construction and demolition (C&D) materials transportation and disposal shall be equipped with Global Positioning System (GPS) or equivalent automatic identification system (AIS) for real time tracking and monitoring of their travel routings and parking locations in order to avoid illegal dumping or landfilling of C&D materials. The data collected by GPS or equivalent AIS relating to travel routings and parking locations of all dump trucks shall be recorded properly for checking and auditing by ET and IEC respectively. Checking and auditing on the travel routings and parking locations collected by GPS was done in the reporting period. No illegal dumping or landfilling of C&D material was found in the reporting period.

The monthly summary of the waste flow table is provided in Appendix G.

5.3 Permit and Licences

The valid environmental permits and licences for the ATCL during the reporting period are summarised in Table 5.2.

Table 5.2: Valid Environmental Permits / Licences

Type of Permit / Licence	Reference No.	Valid From	Valid Till	Remark
Environmental Permit	EP-630/2023/A	1 Dec 2025	--	N/A
Billing Account for Disposal of Construction Waste	7055562	12 Aug 2025	--	N/A
Construction Dust Notification under APCO	10020078	4 Aug 2025	--	N/A
Construction Noise Permit	GW-RS0092-26	6 Feb 2026	6 May 2026	Issued by EPD on 30 Jan 2026
Construction Noise Permit	GW-RS0234-26	12 Mar 2026	11 May 2026	Issued by EPD on 10 Mar 2026
Chemical Waste Producer	5213-951-P3620-01	25 Aug 2025	--	N/A
Water Discharge Licence	WT00048273-2026	23 Mar 2026	31 Mar 2031	Issued by EPD on 23 Mar 2026
Water Discharge Licence	WT00048425-2026	22 Apr 2026	30 Apr 2031	Issued by EPD on 22 Apr 2026

6 Report on the Non-compliances, Complaints, Notifications of Summons and Status of Prosecutions

6.1 Summary of Exceedance of the Environmental Quality Performance Limit

Air Quality

There was no exceedance of the Action or Limit Levels for impact air quality monitoring during the reporting period.

Noise

There was no exceedance of the Action or Limit Levels for impact construction noise monitoring during the reporting period.

Water Quality

The DO and SS monitoring results at all monitoring stations were within the corresponding Action and Limit Levels in the reporting period. One turbidity monitoring result on 2 April 2026 triggered the Action Level. After investigation, it was concluded that the exceedance was not related to the Project.

Statistics on exceedance of the Action or Limit Levels for environmental monitoring are summarized in Table 6.1.

Table 6.1: Statistics on Exceedance of the Action or Limit Levels for Environmental Monitoring

Environmental Monitoring		No. of Exceedances Recorded during the Reporting Period		Cumulative No. of Exceedances Recorded since the Project Commenced
Environmental Monitoring		Project related	Non-project related	Project related	Non-project related
Air Quality	Action Level	0	0	0	0
Air Quality	Limit Level	0	0	0	0
Construction Noise	Action Level	0	0	0	0
Construction Noise	Limit Level	0	0	0	0
Water Quality	Action Level	0	1	0	1
Water Quality	Limit Level	0	0	0	0

6.2 Summary of Complaints, Notifications of Summons and Successful Prosecutions

Complaint Log

There was no complaint received in relation to the environmental impact during the reporting period.

Notifications of Summons or Status of Prosecution

There was no notification of summons or prosecutions received during the reporting period.

Cumulative Statistics

Statistics on complaints, notifications of summons and successful prosecutions are summarized in Table 6.2.

Table 6.2: Statistics on Environmental Complaints, Notifications of Summons and Successful Prosecutions

Reporting Period	Environmental Complaints	Notifications of Summons	Successful Prosecutions
This reporting period (1 – 30 Apr 2026)	0	0	0
From commencement date of construction to end of reporting period	0	0	0

6.3 Implementation Status of Environmental Protection and Pollution Control / Mitigation Measures

The implementation status of environmental protection and pollution control/mitigation measures during the reporting period is presented in Appendix H.

7 Future Key Issues

7.1 Construction Programme for the Upcoming Month

As informed by the Contractor, the major construction activities for the next reporting period are summarized below:

Land-based portion

· Pre-drilling (site preparation works);

· Site clearance (site preparation works);

· Piling works;

· UU diversion works;

· Sheet piling works;

· Hoarding modification works;

· Fixed networks operators (FNO) protection;

· Seawall excavation; and

· UU protection works.

Marine-based portion

· Pre-drilling (site preparation works); and

· Silt curtain and temporary working platform installation.

7.2 Environmental Site Inspection and Monitoring Schedule for the Next Reporting Period

The tentative schedule for weekly site inspection and environmental monitoring for the next reporting period is provided in Appendix F.

8 Conclusions and Recommendations

General

The construction works for the Project commenced on 17 December 2025; therefore, the construction phase EM&A programme of the ATCL Project started on 17 December 2025. The ET of the Project has undertaken environmental site inspections and environmental monitoring under the construction phase EM&A programme during the reporting period.

Environmental Monitoring

The marine construction works of the marine viaduct commenced on 31 March 2026; therefore, the impact water quality monitoring for the marine viaduct started on 31 March 2026. Air quality, noise and water quality monitoring was conducted during the reporting period, and no exceedance for air quality and noise was recorded.

Environmental Site Inspections

Weekly environmental site inspections were conducted during the reporting period. No major deficiency was identified during the site inspections. Nevertheless, recommendations on good practices and mitigation measures were given to the Contractor during the site inspections.

Complaint Log

There was no complaint received in relation to the environmental impact during the reporting period.

Notifications of Summons and Successful Prosecutions

There was no notification of summons or successful prosecutions received during the reporting period.

Reporting Changes

There was no reporting change during the reporting period.

Recommendations on Compliance / Mitigation Measures Implementation

According to the environmental site inspections conducted during the reporting period, the following recommendations were provided:

Air Quality

· Open stockpiles shall be avoided or covered.

· Establishment and use of vehicle wheel and body washing facilities at the exit points of the site.

· Watering on heavy construction work areas.

· Requirements stipulated in the Air Pollution Control (Non-road Mobile Machinery) (Emission) Regulation should be followed to control potential emissions from non-road mobile machinery.

Noise

· Implementation of plant inventory recommended in the submitted CNMP.

· Use of quieter Powered Mechanical Equipment is recommended to reduce the noise impact.

· The use of noise barrier for certain PME (Powered Mechanical Equipment) could generally provide a 5 dB(A) reduction for movable PME and 10 dB(A) for stationary PME. The barrier material shall be long enough and have no opening or gaps.

Water Quality

· Best Management Practices (BMPs) of mitigation measures in controlling water pollution and good site management, as specified in the ProPECC PN 1/94 “Construction Site Drainage” should be followed, where applicable.

· All vehicles and plant should be cleaned before leaving a construction site. An adequately designed and sited wheel washing facilities should be provided.

Waste Management

· Drip tray should be provided to chemical waste containers. The drip tray should be clean up regularly. Clean up should be done before foreseeable inclement weather such as typhoon or heavy rain.