This Quarterly Environmental Monitoring and Audit (“EM&A”) Report summarises project monitoring, and auditing data, with full interpretation illustrating the acceptability or otherwise of any environmental impacts, and identification or assessment of the implementation status of agreed mitigation measures, including monitoring results, and findings of the EM&A Programme, along with findings recorded during the site Inspections, and audits, reports of Complaints, Notifications of Summons, and Successful Prosecutions, and other necessary observations obtained within this reporting quarter from 1 November 2025 to 31 January 2026.

Key Construction Works in the Reporting quarter

San Shek Wan Sewage Treatment Works (“SSWSTW”)

· Superstructure Reinforced Concrete (“RC”) works

· Waterproofing Work

· Backfilling work

· Excavation and Site formation

· Electrical and Mechanical (“E&M”) Installation

· Slope Work near SSWSTW

Pui O Sewage Pumping Station (“POSPS”)

· Excavation, sewer laying, construction of manhole

· Excavation and Excavation and Lateral Support (”ELS”) work

· E&M Installation

Lo Uk Tsuen, Pui O

· Excavation, sewer laying, construction of manhole

South Lantau Road

· Excavation, sewer laying, construction of manhole

Chi Ma Wan Road

· Excavation, sewer laying, construction of manhole

· Trenchless drilling works

Environmental Monitoring, and Audit Progress

The EM&A Programme is implemented in accordance with the EM&A Manual under the EIA Report. A summary of the monitoring activities during this reporting quarter as below:

Monitoring Activity	Monitoring Date
Monitoring Activity	November 2025	December 2025	January 2026
Noise	7, 13-15, 18-20 and 25	1, 11-12, 18, 23-24 and 30	5, 16, 22-23 and 28
Nursery visit for transplanted trees	24	15	12 and 19
Site Inspection	3, 10, 17 and 24	1, 8, 15, 23 and 30	8, 12, 19 and 26

Breaches of Action, and Limit Levels

Noise Monitoring has been conducted at 8 of the designated monitoring locations (N12a, N12b, N13, N14, N15b,

N16a, N16b, and N17) where construction works has been conducted nearby during the reporting month.

Noise limit level exceedance of 75 dB(A) was recorded at N12a on 24 December 2025. Site observation recorded a breaker operating at a roadside works site on South Lantau Road during monitoring. Also, local traffic noise, that comprises of heavy vehicles including trucks and buses, was observed to be high. As such, the exceedance would be due to combination of construction works and traffic flow. Hence, it is considered that the exceedance maybe project-related

Repeat monitoring was conducted on 30 December 2025 due to no construction works during the public holidays on 25–26 December. Corrected noise level of 72dB(A) at N12a was recorded. Site investigation conducted on 30 December 2025 observed that no beaker was in operation at the work site. Corresponding remedial actions, including reminding the Contractor to maintain vigilance over construction noise and implemented proper construction noise mitigation measures according to EM&A Manual and Construction Noise Mitigation Plan. And formalizing the mandatory erection of noise barriers for future concrete breaking activities to prevent the recurrence of similar incidents. The final investigation report was submitted to EPD on 30 January 2026, and the final investigation report is given in Appendix 4.1.

Subsequent to the completion of marine work on 24 May 2025, water quality monitoring was considered completed by 30 May 2025. No water quality monitoring is conducted in this reporting quarter. Should marine works resume, water quality monitoring will be conducted in accordance with the requirement stipulated in the EM&A Manual accordingly.

A summary of environmental exceedances for this reporting quarter is as follows:

Environmental Monitoring	Parameters	Action Level	Limit Level
Noise	L_eq _{(30 min)}	0	1

Ecological Impact Monitoring

Transplanting of the trees of Aquilaris sinensis was completed on 26 April 2022. Maintenance works for trees in holding nursery have commenced.

4 trees found (1 no. of Aquilaria sinensis, and 3 nos. of Gmelina chinensis) within the site of SSWSTW which are considered to be the plant species with conservative importance for temporarily transplanted to the nursery at Kam Tin and eventually be transplanted to POSPS.

The weekly site audit was carried out by ET include checking whether good site practices are being properly implemented by the Contractor.

The extent of the work site boundaries was checked by the ET during the weekly site audit.

Complaints, Notification of Summons and Prosecution

No notification of summons and successful prosecution regarding construction works were recorded in the reporting quarter.

Reporting Changes

There are no reporting changes in the reporting quarter.

1. Introduction

1.1 Project Background

1.1.1 The Environmental Protection Department (“EPD”) completed the Outlying Islands Sewerage Master Plan (“SMP”) Study in 1994 and drew up a SMP for Lantau Island and other outlying islands. The proposed sewerage works of the SMP were divided into 2 stages. The Stage 2 Works of the SMP were subsequently reviewed by EPD under the Outlying Islands Sewerage Master Plan Stage 2 Review (SMP Review Study) in 2001.

1.1.2 The proposed sewerage works for South Lantau were further reviewed in 2008 under the Review of Sewerage Scheme for South Lantau (Review Study). According to the Review Study, the proposed sewerage works for South Lantau would serve the unsewered areas of Shui Hau, Tong Fuk, Cheung Sha, San Shek Wan, Pui O and Ham Tin.

1.1.3 The Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works, herein referred to as “the Project”, referred to the sewerage works for South Lantau that would serve the unsewered areas of Shui Hau, Tong Fuk, Cheung Sha, San Shek Wan, Pui O and Ham Tin.

1.1.4 The Project mainly comprises of the following items:

a) Construction of a secondary sewage treatment works (“STW”) at San Shek Wan in South Lantau;

b) Construction of sewage pumping station (“SPS”) at Pui O, San Shek Wan, Cheung Sha, Cheung Fu Street, Shui Hau and Tong Fuk;

c) Construction of about 1.4km of twin submarine outfalls with a diameter of 350mm for the disposal of treated effluent from the STW at San Shek Wan;

d) Construction of about 10.1km of gravity sewers with diameters ranging from 150mm to 375mm along South Lantau Road and Chi Ma Wan Road and at Pui O; and

e) Construction of about 3.1km of twin rising mains with a diameter of 200mm to 250mm along South Lantau Road and Chi Ma Wan Road.

1.2 Environmental Monitoring & Audit Programme

1.2.1 An Environmental Impact Assessment (“EIA”) was subsequently prepared to review the potential environmental impact that would be due to the Project during its construction works and operational works. The EIA Report was submitted and approved on 24 April 2017, and Environmental Permit (“EP”) No. EP-538/2017 was subsequently granted on 13 July 2017.

1.2.2 The EM&A Programme is therefore implemented in accordance with the EM&A Manual under the EIA Report.

1.2.3 Umwelt Consulting Limited (“UCL”) has been appointed to work as the Environmental Team (“ET”) under EP No. EP-538/2017 to implement the EM&A programme as stipulated in the EM&A Manual of the approved EIA Report for the Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works (Register No.: AEIAR-210/2017).

1.3 Quarterly Environmental Monitoring & Audit Report

1.3.1 This Quarterly EM&A Report summarises project monitoring and auditing data, with full interpretation illustrating the acceptability or otherwise of any environmental impacts and identification or assessment of the implementation status of agreed mitigation measures, including monitoring results and findings of the EM&A Programme, along with findings recorded during the site Inspections and audits, reports of Complaints, Notifications of Summons and Successful Prosecutions, and other necessary observations obtained within this reporting quarter form November 2025 to January 2026.

2. Basic project Information and Environmental Status

2.1 Basic Project Information

2.1.1 Drainage Services Department (“DSD”) is the project proponent and the permit holder of the Project. For the construction phase of the Project, Contractor(s), ET and Independent Environmental Checker (“IEC”) are appointed to manage and control environmental issues. Key personnel and contact particulars are summarized in Table ‎2.1.

2.1.2 Upon conclusion of Contract No: SD 15/2022 Outlying Island Sewerage Stage 2 – South Lantau Sewage Works – Environmental Team Services (2023 – 2024), the subsequent contract, Contract No. CM 04/2024 Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works – Environmental Team Services (2025-2027), has been awarded to Umwelt Consulting Limited (“UCL”) starting 1 February 2025. As such the environmental team leader (“ETL”) appointed for the Project has been updated to Mr. Ting Po Chung, Ivan since 1 February 2025. His contact details has been updated in Table ‎2.1.

2.1.3 There are no other reporting changes in the reporting quarter.

Table ‎2.1: Contact Details of Key Personnel

Party	Role	Post	Name	Contact No.	Contact Fax
Drainage Services Department	The Engineer for the Contract	Engineer	Mr. KK Chan	2594 7297	3104 6426
Binnies Hong Kong Limited	Engineer’s Representative	Resident Engineer	Mr. Kevin Chan	3529 3003	-
Kwan Lee – Chun Wo Joint Venture	Contractor	Sub Agent	Mr. Daniel Chu	6737 6701	2744 6937
		Environmental Supervisor	Ms. Joey Pang	6978 2876
		Environmental Supervisor	Mr. Philip Wong	6908 8920
SMEC Hong Kong	IEC	IEC	Ms. Kitty Lee	3995 8140	3422 3631
Umwelt Consulting Limited	ET	ET Leader	Mr. Ivan Ting	3756 9590	3582 3310

2.2 Construction Programme

2.2.1 The proposed sewerage works will collect the sewage generated from the unsewered areas of Shui Hau, Tong Fuk, Cheung Sha, San Shek Wan, Pui O and Ham Tin in South Lantau (i.e. within the Project Catchment Area) and convey it to a proposed sewage treatment works at San Shek Wan for treatment and disposal into outer bay of Pui O / Chi Ma Wan via a submarine outfall.

2.2.2 The Project was divided into 3 contracts. The current contract, Contract No. DC/2020/02 - Construction of San Shek Wan Sewage Treatment Works, Associated Submarine Outfall and Pui O Sewerage Works (“the Contract”) would have the following implementations. The works site of the Contract is also given in Figure 2.1.

2.2.3 The major components of the Contract under Environmental Permit (“EP”) (EP No. EP-538/2017) comprises:

a) Construction of a secondary sewage treatment works (“STW”) at San Shek Wan in South Lantau;

b) Construction of a sewage pumping station (“SPS”) at Pui O, San Shek Wan, Cheung Sha and Cheung Fu Street;

c) Construction of about 1.4km of submarine outfall with a diameter of 350mm for the disposal of treated effluent from the STW at San Shek Wan;

d) Construction of about 10.1km of gravity sewers with diameters ranging from 150mm to 375mm along South Lantau Road and Chi Ma Wan road and at Pui O; and

e) Construction of about 3.1km twin rising mains with a diameter of 200mm to 250mm along South Lantau Road and Chi Ma Wan Road.

2.3 Works undertaken during the Reporting quarter

2.3.1 In the reporting quarter, the principal work activities conducted are as follow:

San Shek Wan Sewage Treatment Works (“SSWSTW”)

a) Superstructure Reinforced Concrete (“RC”) works

b) Waterproofing Work

c) Backfilling work

d) Excavation and Site formation

e) Electrical and Mechanical (“E&M”) Installation

f) Slope Work near SSWSTW

Pui O Sewage Pumping Station (“POSPS”)

a) Excavation, sewer laying, construction of manhole

b) Excavation and Excavation and Lateral Support (”ELS”) work

c) E&M Installation

Lo Uk Tsuen, Pui O

a) Excavation, Sewer Laying, and Construction of Manhole

South Lantau Road

a) Excavation, Sewer Laying, and Construction of Manhole

Chi Ma Wan Road

a) Excavation, Sewer Laying, and Construction of Manhole

b) Trenchless drilling works

3. Environmental Monitoring and Audit (“EM&A”) Requirement

3.1 Summary of Monitoring Parameters

3.1.1 The EM&A programme requires environmental monitoring, noise monitoring, water quality monitoring, and ecology as specified in the approved EM&A Manual.

3.1.2 A summary of Impact EM&A requirements is presented in Table ‎3.1. The locations of noise monitoring stations, and water quality monitoring stations are shown in Figure 3.1 and Figure 3.2 respectively.

Table ‎3.1: Summary of Impact EM&A Requirements

Environmental Monitoring Aspects

Parameters and Unit

Monitoring Station

Frequencies

Remarks

Noise

L_eq_(30mins),

L_{10 (30mins)} and

L_{90 (30mins)}

N12a, N12b, N13, N14, N15b, N16a, N16b, and N17

At least once per week

Daytime on normal weekdays (0700-1900 hrs).

Water Quality

Dissolved Oxygen, mg/L

Temperature, °C

Salinity, 0/00

Turbidity, NTU

Suspended Solids, mg/L

CE, CF, SR4, SR5, SR6, SR9, SR10, SR12, and SR15

Three times per week during mid-ebb, and mid-flood tides

Samples are collected at 3 depths (1 m below water, mid-depth, and 1 m above seabed) shall be collected.

Where the water depth is less than 6 m, in which case the mid-depth station may be omitted.

Should the water depth be less than 3 m, only the mid-depth station will be monitored

3.2 Environmental quality performance limits (Action and Limit levels); and Results Summary

Noise Monitoring

3.2.1 A-weighted equivalent continuous sound pressure level (“L_eq”) over a period of 30 minutes L_eq₍_30min₎ shall be used as the monitoring parameter for construction noise monitoring. Supplementary information for data auditing, statistical results such as L₁₀, and L₉₀ should also be recorded for reference.

3.2.2 For impact monitoring of construction works, noise monitoring should be undertaken on weekly basis. Six consecutive L_eq_(5min) between 07:00-19:00 hours on normal weekdays is taken in this EM&A Programme.

3.2.3 The Action and Limit Levels for noise monitoring are given as in Table ‎3.2. No examination was conducted during the reporting quarter.

Table ‎3.2: Action and Limit Levels for Noise Monitoring

Monitoring Station ID	Monitoring Location	Action Level	Limit Level
N12a	Lo Uk Tsuen	When one documented complaint is received from any one of the noise sensitive receivers	75 dB(A)
N12b	Lo Uk Tsuen		75 dB(A)
N13	Pui O San Wai Tsuen		75 dB(A)
N14	South Lantau Community Centre		75 dB(A)
N15b	Pui O Lo Wai Tsuen		75 dB(A)
N16a	Residences at Ham Tin		75 dB(A)
N16b	Residences at Ham Tin		75 dB(A)
N17	Bui O Public School		70 dB(A) / 65 dB(A) ¹

Note:

1. The Limit Level for N17 is 70 dB(A) for being an educational institution. The Limit Level is reduced to 65 dB(A) during school examination period.

3.2.4 Noise limit level exceedance of 75 dB(A) was recorded at N12a on 24 December 2025. Site observation recorded a breaker operating at a roadside works site on South Lantau Road during monitoring. Also, local traffic noise, that comprises of heavy vehicles including trucks and buses, was observed to be high. As such, the exceedance would be due to combination of construction works and traffic flow. Hence, it is considered that the exceedance maybe project-related

3.2.5 Repeat monitoring was conducted on 30 December 2025 due to no construction works during the public holidays on 25–26 December. Corrected noise level of 72dB(A) at N12a was recorded. Site investigation conducted on 30 December 2025 observed that no beaker was in operation at the work site. Corresponding remedial actions, including reminding the Contractor to maintain vigilance over construction noise and implemented proper construction noise mitigation measures according to EM&A Manual and Construction Noise Mitigation Plan. And formalizing the mandatory erection of noise barriers for future concrete breaking activities to prevent the recurrence of similar incidents. The final investigation report was submitted to EPD on 30 January 2026, and the final investigation report is given in Appendix 4.1.

3.2.6 The detailed results and graphical plot for noise monitoring is given in Appendix 3.1.

Water Quality Monitoring

Completion of Water Quality Monitoring

3.2.7 Subsequent to the completion of marine work on 24 May 2025, water quality monitoring

was considered completed by 30 May 2025. No water quality monitoring was conducted during the reporting quarter. Should marine works resume, water quality monitoring will be conducted in accordance with the requirement stipulated in the EM&A Manual accordingly.

Ecological Impact Monitoring

3.2.8 Monitoring in the form of regular site inspections should be carried out to ensure ecological measures in the form of tree transplantation, and establishment are being implemented, and effective for plant species of conservation importance (e.g. Aquilaria sinensis).

3.2.9 Transplanting works for plant species, Aquilaris sinensis, was completed on 26 April 2022. Maintenance works for trees in holding nursery have commenced.

3.2.10 Monitoring of maintenance works for the transplanted plant species was conducted at the holding nursery while in the reporting period.

3.2.11 As per latest version of PTP, four tree found (1 no. of Aquilaria sinensis, and 3 nos. of Gmelina chinensis) within the site of SSWSTW which are considered to be the plant species with conservative importance for temporarily transplanted to the nursery at Kam Tin and eventually be transplanted to POSPS.

3.2.12 Within this reporting period, holding nursery visit for transplanted trees on 24 November, 15 December 2025, 12 and 19 January 2026

3.2.13 No non-compliance was found during the site inspection while reminders on environmental measures were recommended. Results and findings of these inspections in this reporting period are listed below in Table 3.4.

Table 3.4: Summary of Ecological Impact Monitoring

Inspection Date	Reminder and Recommendations	Close-out Date / Status
24 November 2025	Nil	--
15 December 2025	Nil.	--
12 January 2026	Nil.	--
19 January 2026	Nil.	--

Waste Management

3.2.14 The quantities of waste for disposal in present quarter are summarized in Table ‎3.5.

Table ‎3.5: Summary of Quantities of Waste Material in the Reporting Quarter

Waste Type	Quantity for Reporting Quarter	Cumulative Quantity-to-Day
Hard Rock and Large Broken Concrete (Inert), in ‘000m³	0	0
Reused in this Contract (Inert),in ‘000m³	0	0
Reused in other Projects (Inert), in ‘000m³	0	0
Disposal as Public Fill (Inert), in ‘000m³	0.77	31.39789
Metals (in ‘000kg)	1.16	115.14617
Paper / Cardboard Packing, in ‘000kg	0.149	1.51928
Plastics in ‘000kg	0.0096	0.12176
Chemical Waste in ‘000kg	0	0
General Refuse in ‘000kg	270.16	1353.99

Note:

The table is summary of quantities of waste material of November 2025 to January 2026 period.

3.3 Implementation Status of Environmental Mitigation Measures

3.3.1 The mitigation measures recommended in the EIA Report has been implemented where applicable. The implemented mitigation measures for the reporting quarter are listed below:

a) Prevention of site runoff during heavy rainstorms;

b) Implementation of noise pollution control in accordance with Construction Noise Mitigation Plan;

c) Dust control during dust generating works;

d) Adopt surface drainage and sediment control facilities for sewage installation in village and public roads;

e) Adopt temporary drainage and sediment control facilities on Site;

f) Vehicle wheel-washing and body washing facilities should be provided at the site entrance;

g) Regular water spraying on excavation works for dust control; and

h) Proper waste handling, recycling and storage.

3.3.2 The implemented mitigation measures are considered effective.

3.4 Complaints, Non-Compliance, and Notification of Summons and Prosecution

Environmental Complaints Received

3.4.1 No environmental complaint was recorded in the reporting quarter.

Environmental Non-Compliance(exceedance)

3.4.2 The detail of exceedance has been discussed in Section 3.2.4-3.2.5.

Notifications of Summons and Successful Prosecutions

3.4.3 No notification of summons and successful prosecution regarding construction works were recorded in the reporting quarter.

4. Conclusion

4.1 Environmental Monitoring and Audits

4.1.1 Environmental monitoring and audits including Noise, Water Quality, Ecology, and Site audits have been conducted in the reporting quarter in accordance with the requirement stipulated in the EM&A Manua.

Noise Monitoring

4.1.2 Noise Monitoring has been conducted at 8 of the designated monitoring locations where construction works has been conducted nearby during the reporting period.

4.1.3 Noise limit level exceedance of 75 dB(A) was recorded at N12a on 24 December 2025. Site observation recorded a breaker operating at a roadside works site on South Lantau Road during monitoring. Also, local traffic noise, that comprises of heavy vehicles including trucks and buses, was observed to be high. As such, the exceedance would be due to combination of construction works and traffic flow. Hence, it is considered that the exceedance maybe project-related

4.1.4 Repeat monitoring was conducted on 30 December 2025 due to no construction works during the public holidays on 25–26 December. Corrected noise level of 72dB(A) at N12a was recorded. Site investigation conducted on 30 December 2025 observed that no beaker was in operation at the work site. Corresponding remedial actions, including reminding the Contractor to maintain vigilance over construction noise and implemented proper construction noise mitigation measures according to EM&A Manual and Construction Noise Mitigation Plan. And formalizing the mandatory erection of noise barriers for future concrete breaking activities to prevent the recurrence of similar incidents. The final investigation report was submitted to EPD on 30 January 2026, and the final investigation report is given in Appendix 4.1

Water Quality Monitoring

4.1.5 Subsequent to the completion of marine work on 24 May 2025, water quality monitoring was considered completed by 30 May 2025. No water quality monitoring is conducted in this reporting period.

Ecological Impact Monitoring

4.1.6 Transplanting of the trees of Aquilaris sinensis was completed on 26 April 2022. Maintenance works for trees in holding nursery have commenced.

4.1.7 As per latest version of PTP, 4 tree found (1 no. of Aquilaria sinensis and 3 nos. of Gmelina chinensis) within the site of SSWSTW which are considered to be the plant species with conservative importance for temporarily transplanted to the nursery at Kam Tin and eventually be transplanted to Pui O Pumping Station.

4.1.8 The weekly site audit was carried out by ET include checking whether good site practices are being properly implemented by the Contractor.

4.1.9 The extent of the work site boundaries was checked by the ET during the weekly site audit.

4.1.10 No non-compliance was found during the site inspection while reminders on environmental measures were recommended.

4.2 Complaints, Notification of Summons and Prosecution

4.2.1 No environmental complaint, notification of summons and successful prosecution regarding construction works were recorded in the reporting quarter.

4.3 Implementation of Environmental Mitigation Measures

4.3.1 The mitigation measures recommended in the EIA Report has been implemented where applicable. The implemented mitigation measures are considered effective.

Contract No. CM 04/2024 – Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works – Environmental Team Services (2025 - 2027)
Quarterly Environmental Monitoring, and Audit Report for: November to January 2026 Revision 2
	Certified By: ______________ Lau Hoi Wai, Josephine Environmental Team Leader Report Date: 24 March 2026