This is the 6^th Monthly Environment Monitoring and Audit (EM&A) Report for Relocation of Diamon Hill Fresh Water and Salt Water Service Reservoirs to Caverns (the Project). This report was prepared by Acuity Sustainability Consulting Limited under Contract No. 21/WSD/21 (hereafter called “the Contract”). This report documents the findings of EM&A works during the reporting period from 1 September to 30 September 2023.

Key Construction Works in the Reporting Period

A summary of construction activities undertaken during the reporting period is presented below:

· Open trench for main laying and main laying;

· Jacking pit construction for pipe jacking;

· Trial pit excavation;

· Formation of piling platform at +89.0mPD;

· Pipe piling for Portal Ancillary Building Excavation and Lateral Support wall;

· Site compound set up; and

· ELS works in Portion 3.

Environmental Monitoring and Audit Programme

The monthly EM&A programme was undertaken by the Environmental Team in accordance with the EM&A Manual. A summary of the monitoring and audit activities during the reporting period is presented below:

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

EM&A Activities	Date
1-hour TSP Monitoring	4, 7, 13, 19, 25 and 29 September 2023
Construction Noise Monitoring	4, 7, 13, 19 and 25 September 2023
Weekly Environmental Site Inspection	13, 22 and 27 September 2023

Note:

1. The site inspection scheduled on 8 September 2023 was cancelled due to adverse weather.

Breaches of Action and Limit Levels

A summary of the environmental monitoring exceedance of the reporting period is tabulated in Table II.

Table II Summary of Exceedance in the Reporting Period

Environmental Monitoring	Parameter	No. of non-project related exceedances		Total no. of non-project related exceedances	No. of exceedances related to the project		Total no. of exceedances related to the project
Environmental Monitoring	Parameter	AL	LL	Total no. of non-project related exceedances	AL	LL	Total no. of exceedances related to the project
Air Quality	1-hour TSP	0	0	0	0	0	0
Noise	L_eq_(30-min)	0	0	0	0	0	0

Note:

2. AL refers to Action Level and LL refers to Limit Level.

Air Quality

No exceedance of Action Level or Limit Level was recorded for 1-hour TSP monitoring during the reporting period.

Construction Noise

No Action Level exceedance was recorded for construction noise monitoring during the reporting period.

No Limit Level exceedance was recorded for construction noise monitoring during the reporting period.

Complaint Log

No environmental complaint was received in the reporting period.

Notification of Summons and Successful Prosecutions

No notification of summons or successful prosecutions was received in the reporting period.

Reporting Change

There was no reporting change in the reporting period.

Future Key Construction Activities

Key construction activities to be considered in the next two months included:

· Open trench for main laying and main laying;

· Jacking pit construction for pipe jacking;

· Trial pit excavation;

· Pipe piling for Portal Ancillary Building Excavation and Lateral Support wall; and

· ELS works in Portion 3.

Potential environmental impacts arising from the above construction activities are mainly associated with construction dust, construction noise, water pollution control, waste management and landscape and visual.

1. InTroduction

1.1 Project Background

1.1.1 The relocated Diamond Hill Fresh Water and Salt Water Service Reservoirs (DHSRs) will be constructed in a series of caverns linked by access tunnels and adits. The relocated Diamond Hill Fresh Water Service Reservoirs (DHFWSR) and Diamond Hill Salt Water Service Reservoirs (DHSWSR) will be compartmented while the existing Diamond Hill Pumping Station (DHPS) will be split into two (2) pump houses for fresh and salt water supply when relocated.

1.1.2 Ancillary facilities to be constructed near the tunnel portal may include transformer room, switch room, emergency generator room, control room, ventilation building, and pumping station control room, which will be constructed in an above-ground building outside the tunnel.

1.1.3 The scope of the Project comprises the following:

a) Construction of the relocated DHSRs and associated pumping stations and water main laying works;

b) Construction of tunnels, adits, ventilation system and caverns for accommodating the relocated DHSRs and the associated facilities;

c) Terminating the operation of the existing DHSRs and the associated facilities; and

d) All other associated works that are incidental to and necessary for the completion of the Project.

1.1.4 The major construction activities of the Project include earthworks, drilling and blasting, construction of concrete structures, handling and transportation of excavated materials, water mains laying, installation of electrical and mechanical (E&M) equipment and material transportation. The operation of the existing DHSRs and the associated facilities will be terminated after the completion of the testing and commissioning of the relocated DHSRs. Under the Project, the existing DHSRs and associated facilities will be retained after termination of the operation. The subsequent demolition works will be carried out by other government departments/ project proponents.

1.1.5 The Project construction was commenced on 31 March 2023 and the completion date for the construction works would be on 12 April 2027.

1.1.6 The Project is a Designated Project under Item Q.2, Part I of Schedule 2 of the Environmental Impact Assessment Ordinance, "Underground Rock Caverns", which requires an environmental permit from Environmental Protection Department for its construction and operation.

1.1.7 Pursuant to the Environmental Impact Assessment Ordinance (EIAO), the Director of Environmental Protection Department (EPD) granted the Environmental Permits (EP-602/2021) to the Water Supplies Department (WSD) for the Project.

1.1.8 Acuity Sustainability Consulting Limited (ASCL) is commissioned by Chun Wo – Sinohydro Joint Venture to undertake the role of Environmental Team under the Environmental Permit (EP) EP-602/2021, and to carry out the EM&A programme in fulfilment of the EM&A Manual, and other requirements stipulated in the associated EIA Report.

1.1.9 This is the 6^th Monthly EM&A Report summarizing the key findings of the construction phase EM&A programme from 1 September to 30 September 2023 (the reporting period) and is submitted to fulfil the requirements in Conditions 3.4 of EP-602/2021 and section 13.3 of the EM&A Manual of the Project.

1.2 Construction Works Programme

1.2.1 The construction works of the Project was commenced on 31 March 2023. The construction works programme, and the location of construction works of the Project are shown in Appendix A and Figure 1.1, respectively. A summary of construction activities undertaken during the reporting period is presented below:

· Open trench for main laying and main laying;

· Jacking pit construction for pipe jacking;

· Trial pit excavation;

· Formation of piling platform at +89.0mPD;

· Pipe piling for Portal Ancillary Building Excavation and Lateral Support wall;

· Site compound set up; and

· ELS works in Portion 3.

1.3 Project Organization

1.3.1 Different parties with different levels of involvement in the Project organization include:

· Project Proponent: Water Supplies Department (WSD)

· Supervisor/Engineer’s Representative (ER): Binnies Hong Kong Limited

· Contractor: Chun Wo - Sinohydro Joint Venture

· Environmental Team (ET): Acuity Sustainability Consulting Limited

· Independent Environmental Checker (IEC): Umwelt Consulting Limited

1.3.2 The key personnel contact names and telephone number are presented in Appendix B.

1.4 License, Notification and Permits

1.4.1 A summary of the relevant permit, licences, and/ or notifications on environmental protection for this Project are presented in Table 1.1.

Table 1.1 Status of Environmental License, Notifications and Permits

Permit / License No.	Valid Period		Status
Permit / License No.	From	Expired On	Status
Environmental Permit
EP-602/2021	14/12/2021	-	Valid
Notification Pursuant to Section 3(1) of the Air Pollution Control (Construction Dust) Regulation
Ref. No.: 487301	09/12/2022	-	Valid
Billing Account for Disposal of Construction Waste
7046085	04/01/2023	-	Valid
Registration of Chemical Waste Producer
WPN 5213-282-C4760-0	30/12/2022	-	Valid
Effluent Discharge License under Water Pollution Control Ordinance
WT00043965-2023	31/05/2023	31/05/2028	Valid
Construction Noise Permit
GW-RE1015-23	01/09/2023	31/12/2023	Valid

1.4.2 The submission status of the EP and the implementation status of the mitigation measures stated in the EP had been reviewed, all submission were submitted/ deposited to the Director of Environmental Protection (DEP) on schedule, no non-compliance of EP conditions was recorded during the reporting period. The summary of submission status under Environmental Permit EP-602/2021 are summarized in Table 1.2.

Table 1.2 Summary of Status of Submission under EP-602/2021

EP Condition	Title of Submission	Submission Status
1.11	Commencement Date of Construction	Notified the DEP on 22 Feb 2023
2.9	Management Organization(s)	Informed the DEP on 20 Feb 2023
2.10	Environmental Permit (EP) Submission Schedule	22 Feb 2022 (1st Submission)
2.11	Construction Works Schedule and Location Plan	28 Feb 2023 (Deposited)
2.12	Construction Noise Management Plan (CNMP)	· 28 Feb 2023 (1st submission) · The EPD’s comments were issued on 8 Mar 2023 · The revised CNMP was submitted to the EPD for comment on 31 Jul 2023. · The EPD issued further comments on 16 Aug 2023. · The CNMP was further revised, certified by the ET Leader, verified by the IEC, and issued to the EPD on 22 Aug 2023. · The revised CNMP was submitted to the EPD for comment on 15 Sept 2023.
2.13	Waste Management Plan (WMP)	· 28 Feb 2023 (1st submission) · EPD’s comments were issued on 3 Apr 2023. · The revised WMP was submitted to the EPD for comment on 26 July 2023. · The WMP was further updated and submitted to the EPD on 16 Aug 2023. · The EPD had no further comment on 19 Sept 2023.
2.14	Landscape and Visual Mitigation Plan (LVMP)	· 28 Feb 2022 (1st Submission) · EPD’s comments were issued on 29 Mar 2023. · The revised LVMP was certified by the ET Leader, verified by the IEC, and issued to the EPD on 22 Aug 2023.
3.3	Baseline Monitoring Report	· 17 Mar 2023 (1st Submission) · 27 Apr 2023 (2nd Submission) · 1 June 2023 (3rd Submission) · 13 July 2023 (Formal submission) · 3 Aug 2023 (accepted by the EPD)
3.4	Monthly EM&A Report (August 2023)	13 September 2023
4.2	Dedicated Internet Website	2 May 2023

1.4.3 Following the EPD’s comments on the Baseline Monitoring Report (Ref. No. BMR-3.1, dated 17 March 2023), updating of air quality and noise monitoring locations were proposed, including cancellation of noise monitoring station at Tower 1, Meridian Hill (NM-1), resumption of air quality and noise monitoring stations at Block 6, Tsui Chuk Garden (i.e. DM-4 and NM-4) and proposal of new noise monitoring locations at Wo Tin House, Shatin Pass Estate (NM-5) and Sheung Fung Street Customs Staff Quarter (NM-6).

1.4.4 Additional baseline monitoring for air quality monitoring station DM-4, and noise monitoring stations NM-4, NM-5 and NM-6 was carried out between 2 May and 16 May 2023. The Baseline Monitoring Report was updated with all baseline monitoring results included, certified by the ET Leader, and verified by the IEC on 30 May 2023. The updated Baseline Monitoring Report was submitted to the EPD on 1 June 2023. A minor comment was received from the EPD on 26 June 2023. Following the advice from the EPD, the Report was formally submitted to the EPD on 13 July 2023 after amendment. The Report was accepted by the EPD on 3 August 2023.

1.5 Brief Summary of EM&A Requirements

Air Quality

1.5.1 In accordance with the EM&A Manual, the ET shall carry out impact monitoring during construction phase of the project. For 1-hour Total Suspended Particulates (TSP) monitoring, the sampling frequency of at least three times every six days should be undertaken when the highest dust impact occurs.

1.5.2 Action and Limit Levels for the 1-hour TSP monitoring works are discussed in Section 2.4. Should non-compliance of the criteria occur, action in accordance with the Event and Action Plan presented in Appendix C shall be carried out.

1.5.3 The air quality mitigation measures detailed in the EM&A Manual were recommended to be implemented during the construction phase. The implementation statuses of these measures are presented in Appendix D.

Noise Monitoring

1.5.4 Construction noise monitoring should be carried out at the designated monitoring stations directly affected by the construction works once every week after the commencement of construction. During construction works, one set of L_eq_(30-min) measurement at each station between 0700 and 1900 hours on normal weekdays shall be taken. If construction works are extended to include works during the period between 1900 and 0700 hours, additional weekly impact monitoring shall be carried out during evening and night-time works.

1.5.5 Action and Limit Levels for the noise monitoring are discussed in Section 3.5. Should non-compliance of the criteria occur, action in accordance with the Event and Action Plan presented in Appendix C shall be carried out.

1.5.6 The noise mitigation measures detailed in the EM&A Manual are recommended to be implemented during the construction phase. The implementation statuses of these measures are presented in Appendix D.

Environmental Requirements in Contract Documents

1.5.7 According to Particular Specification (PS), the Contractor shall undertake environmental protection measures to reduce the environmental impacts arising from the execution of the works. The Contractor shall also observe and comply with relevant environmental protection and pollution control ordinances. The Contractor shall design, construct, operate and maintain pollution control measures to ensure compliance with the contract provisions as well as the environmental ordinances and their regulations.

1.5.8 The Contractor shall also:

· Implement air pollution and noise abatement practices as specified in PS;

· Minimise generation of wastewater from the Site;

· On-site sorting of Construction and Demolition (C&D) Materials;

· Establish a mechanism to record the quantities of C&D materials generated each month, using the monthly summary “Waste Flow Table”;

· Control the use of timbers;

· Implement a trip ticket system (TTS) for tracking the removal of C&D materials from the Site to the disposal grounds;

· Prepare an Environmental Management Plan (EMP) in accordance with GS Section 25 and PS for implementation on the Site to reduce environmental nuisance and C&D materials arising from Works, throughout the construction period;

· Arrange weekly environmental walk to inspect the Site, checking that the environmental performance of the Site is satisfactory and in compliance with the requirements under the contract and EMP; and

· Carry out site specific induction training about environmental management as well as safety for all staffs and workers, and provide toolbox talks for workers on environmental nuisance abatement and waste management.

2. Air QualiTy monitoring

2.1 Monitoring Locations

2.1.1 The air quality monitoring locations for impact monitoring during the reporting period are listed in Table 2.1 and presented in Figure 2.1.

Table 2.1 Air Quality Monitoring Stations for Construction Phase

ID	Description	Coordinates
ID	Description	Northing	Easting
DM-1	Tennis Court near Tin Ma Court	822705	837047
DM-2	Chun Sing House, Tin Ma Court	822673	837143
DM-3	Grace Methodist Church Kindergarten	822782	837227
DM-4 ⁽¹⁾	Block 6, Tsui Chuk Garden	822926	837246
DM-4a ⁽²⁾	Road pavement near Wang King House, Tin Wang Court	822854	837340

Notes:

1. Following the EPD’s comment on the Baseline Monitoring Report (Ref. No. BRM-3.1, dated 17 March 2023), air quality monitoring at DM-4 was resumed. Baseline monitoring for air quality monitoring station DM-4 was then carried out between 2 May and 16 May 2023. Impact monitoring at DM-4 was commenced on 22 May 2023.

2. An additional air quality monitoring station DM-4a was proposed by the ET and agreed by the ER, IEC and EPD.

2.2 Air Quality Monitoring Parameter, Frequency and Duration

2.2.1 Table 2.2 summarized the monitoring parameter, duration, and frequency of impact air quality monitoring.

Table 2.2 Impact Air Quality Monitoring Parameter, Duration and Frequency

Parameter	Frequency	Duration
1-hour TSP	3 times every 6 days	Throughout the construction phase

2.3 Monitoring Equipment and Methodology and QA/ QC Procedure

Proposal of Using Portable Direct Reading Dust Meter

2.3.1 Direct reading dust meters were used for measuring 1-hour TSP levels during the impact air quality monitoring. According to Section 4.4.1 of the EM&A Manual, the proposed use of direct reading dust meters was submitted to and agreed by the IEC.

2.3.2 Sufficient number of monitoring instruments was prepared by the ET for carrying out the impact monitoring. All equipment and associated instrumentation were clearly labelled.

2.3.3 Wind data were collected from the records of Hong Kong Observatory Kai Tak Wind Station (22.30966N, 114.21336E), which is located at the south-eastern side of runway of the former Kai Tak Airport about 4.5 km south-east from the project site.

2.3.4 Equipment used in the impact air quality monitoring programme is summarised in Table 2.3. Calibration certificates for the impact air quality monitoring equipment are attached in Appendix E.

Table 2.3 Impact Air Quality Monitoring Equipment

Equipment	Brand and Model	Serial No.	Calibration Due Date
Direct Reading Dust Meter	Sibata LD-5R	0Z4545	29/02/2024
		882106	29/02/2024
		942532	29/02/2024

Maintenance and Calibration

2.3.5 Direct reading dust meters have been calibrated against high volume samplers (HVSs) annually. A 2-day, three 3-hour measurement results per day from direct reading dust meters were taken to compare with the sampling results from the HVSs. The correlation between the direct reading dust meters and the HVSs were then concluded. By accounting for the correlation factor, the direct reading dust meters are considered to achieve comparable results as that of the HVSs.

2.3.6 The 1-hour TSP measurement follows the instruction provided in the manufacturer's manual. Before initiating a measurement, zeroing the portable dust meter was carried out to ensure the accuracy of each measurement.

2.4 Action and Limit Levels

2.4.1 The action and limit levels were established in accordance with the EM&A Manual. Table 2.4 presents the action and limits levels for 1-hour TSP monitoring. Should non-compliance of the criteria occur, action in accordance with the Event and Action Plan presented in Appendix C shall be carried out.

Table 2.4 Action and Limit Levels for 1-hour TSP

Monitoring Station	Action Level (µg/m³)	Limit Level (µg/m³)
DM-1	300.1	500
DM-2	289.0
DM-3	289.7
DM-4	294.9
DM-4a	291.6

2.5 Results and Observation

2.5.1 The impact air quality monitoring was conducted on 4, 7, 13, 19, 25 and 29 September 2023. The 1-hour TSP monitoring scheduled on 1 September 2023 was postponed to 4 September 2023 due to adverse weather. The impact air quality monitoring schedule for the reporting period is shown in Appendix F.

2.5.2 The monitoring results and graphical presentation of impact air quality monitoring are shown in Appendix G. No action or limit levels exceedance was recorded in the reporting period.

Table 2.5 Summary of Impact 1-hour TSP Monitoring Results

Monitoring Station	TSP Concentration, μg/m³			Action Level	Limit Level
Monitoring Station	Average	Minimum	Maximum	Action Level	Limit Level
DM-1	63	52	79	300.1	500
DM-2	59	48	69	289.0
DM-3	62	53	71	289.7
DM-4 ⁽¹⁾	61	49	71	294.9
DM-4a	64	58	69	291.6

Remark: (1) Impact air quality monitoring at DM-4 was commenced on 22 May 2023.

2.5.3 During the impact air quality monitoring, the major dust sources at each monitoring stations were summarized in Table 2.6.

Table 2.6 Influencing Factors at/ near Air Quality Monitoring Stations

Monitoring Stations	Influencing Factors
DM-1	Not identified
DM-2	Not identified
DM-3	Not identified
DM-4	Not identified
DM-4a	Not identified

2.5.4 Weather conditions during impact monitoring are presented in Appendix G and extracts of wind data recorded at Kai Tak Wind Station available from the Hong Kong Observatory are presented in Appendix H.

3. NOiSE Monitoring

3.1 Monitoring Locations

3.1.1 The monitoring locations for construction noise monitoring are listed in Table 3.1 and shown in Figure 3.1.

Table 3.1 Noise Monitoring Stations during Construction Phase

ID	Description	Measurement	Coordinates
ID	Description	Measurement	Northing	Easting
NM-2	Chun Sing House, Tin Ma Court	Façade	822668	837143
NM-3	Grace Methodist Church Kindergarten	Façade	822782	837227
NM-4 ⁽²⁾	Block 6, Tsui Chuk Garden	Façade	822926	837246
NM-4a ⁽¹⁾	Road pavement near Wang King House, Tin Wang Court	Free field	822854	837340
NM-5 ⁽³⁾	Wo Tin House, Shatin Pass Estate	Façade	823360	838143
NM-6 ⁽³⁾	Sheung Fung Street Customs Staff Quarters	Free field	823134	838412

Notes:

The noise monitoring station proposed in the EM&A Manual (NM-1) was not available for baseline and impact monitoring. Therefore, impact monitoring at NM-1 was cancelled and agreed by the ER, IEC and EPD.

(1) An additional noise monitoring station NM-4a was proposed by the ET and agreed by the ER, IEC and EPD.

(2) Following the EPD’s comment on the Baseline Monitoring Report (Ref. No. BRM-3.1, dated 17 March 2023), noise monitoring station was resumed at NM-4. Baseline monitoring for noise monitoring station NM-4 was then carried out between 2 May and 16 May 2023. Impact monitoring at NM-4 was commenced on 22 May 2023.

(3) Main laying works near NM-5 and NM-6 were commenced in early September 2023. Noise monitoring at NM-5 and NM-6 was commenced on 7 September 2023.

3.1.2 Following the commencement of main laying works near the noise monitoring stations NM-5 and NM-6 in early September 2023, construction noise monitoring programme at these two stations was begun on 7 September 2023.

3.2 Noise Monitoring Parameter, Frequency and Duration

3.2.1 Construction noise level was measured by the ET and measured in terms of the A-weighted equivalent continuous sound pressure level (L_eq). L_eq_(30-min)was adopted as the monitoring parameter for the construction noise monitoring.

3.2.2 As supplementary information for data auditing, statistical results such as L₁₀ and L₉₀ were also obtained for reference.

3.2.3 Table 3.2 summarized the monitoring parameters, duration, and frequency of construction noise monitoring.

Table 3.2 Construction Noise Monitoring Parameter, Frequency and Duration

Parameters	Time	Frequency	Duration
L_eq_(30-min)	0700 and 1900 hours on normal weekdays	once every week	Throughout the construction phase

3.3 Monitoring Equipment, Methodology and QA / QC Procedure

3.3.1 As referred to the technical memorandum (TM) issued under the NCO, sound level meters in compliance with the International Electrotechnical Commission Publications 651: 1979 (Type 1) and 804: 1985 (Type 1) specifications were used for carrying out the construction noise monitoring.

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

3.3.3 Sufficient number of noise measuring equipment and associated instrumentation were prepared by the Environmental Team. All the equipment and associated instrumentation were clearly labelled.

3.3.4 Wind data were collected from the records of Hong Kong Observatory Kai Tak Wind Station (22.30966N, 114.21336E), which is located at the south-eastern side of runway of the former Kai Tak Airport about 4.5 km south-east from the project site.

3.3.5 The monitoring procedures are as follows:

· For façade measurement, the monitoring station was set at a point 1 m from the exterior of the sensitive receiver building façade and set at a position 1.2 m above the ground. For free-field measurement, the monitoring station was set at a position 1.2 m above the ground.

· The battery condition was checked to ensure good functioning of the meter.

· Parameters such as frequency weighting, the time weighting and the interval were set as follows:

· Frequency weighting: A

· Time weighting: Fast

· Interval: 30 minutes (L_eq_(30-min)) would be determined for daytime noise by calculating the logarithmic average of six L_eq_(5-min)data

· Prior to and after each noise measurement, the meter was calibrated using an acoustic calibrator for 94.0 dB at 1000 Hz. If the difference in the calibration level before and after measurement is more than 1.0 dB, the measurement was considered invalid and repeat of noise measurement will be required after re-calibration or repair of the equipment.

· At the end of the monitoring period, the values of L_eq, L₉₀ and L₁₀ were recorded. In addition, noise sources were recorded on a standard record sheet.

3.3.6 Table 3.3 summarized the noise monitoring equipment used during the construction noise monitoring. Calibration certificates for the impact noise monitoring equipment are attached in Appendix E.

Table 3.3 Construction Noise Monitoring Equipment

Equipment	Model (Serial Number)	Calibration Due Date
Sound Level Meter	NTi-XL2 (A2A-13663-F0)	14/02/2024
Sound Level Meter	NTi-XL2 (A2A-13548-E0)	05/02/2024
Sound Level Meter	NTi-XL2 (A2A-17638-E0)	03/04/2024
Sound Calibrator	Rion NC 75 (35124527)	01/11/2023
Sound Calibrator	Rion NC 75 (35124530)	01/11/2023

3.4 Maintenance and Calibration

3.4.1 Maintenance and calibration procedures are as follows:

· The microphone head of the sound level meter and calibrator were regularly cleaned with a soft cloth; and

· The sound level meter and acoustic calibrator were calibrated annually by a HOKLAS accredited laboratory or the manufacturer.

3.5 Action and Limit Levels

3.5.1 The Action and Limit Levels were established in accordance with the EM&A Manual. Table 3.4 presents the Action and Limit Levels for construction noise. Should non-compliance of the criteria occur, action in accordance with the Event and Action Plan presented in Appendix C shall be carried out.

Table 3.4 Action and Limit Levels for Construction Noise Monitoring

Monitoring Stations	Action Level	Limit Level	Time Period
NM-2	When one documented complaint is received	75 dB(A)	0700 - 1900 hours on normal weekdays
NM-3		70/ 65 dB(A) *
NM-4		75 dB(A)
NM-4a		75 dB(A)
NM-5		75 dB(A)
NM-6		75 dB(A)

Notes:

If works are to be carried out during restricted hours, the conditions stipulated in the construction noise permit issued by the Noise Control Authority have to be followed.

* 70 dB(A) for school and 65 dB(A) during school examination period.

3.6 Results and Observations

3.6.1 The construction noise monitoring was conducted on 4, 7, 13, 19 and 25 September 2023. The construction noise monitoring scheduled on 1 September 2023 was postponed to 4 September 2023 due to adverse weather. The monitoring schedule is presented in Appendix F.

3.6.2 The construction noise monitoring results are summarized in Table 3.5. No Action Level or Limit Level exceedance was recorded in the reporting period. Details of the results and graphical presentation are shown in Appendix I.

Table 3.5 Summary of Construction Noise Monitoring Results

Monitoring Station	Noise Level, dB(A)			Limit Level
	**L_eq_(30-min)**			Limit Level
	Mean	Minimum	Maximum
NM-2	69.9	69.2	70.6	75 dB(A)
NM-3	68.4	66.4	70.0	70/ 65 dB(A) ⁽¹⁾
NM-4 ⁽²⁾	67.5	65.0	69.5	75 dB(A)
NM-4a	71.5	70.8	72.1	75 dB(A)
NM-5 ⁽³⁾	66.3	64.2	67.5	75 dB(A)
NM-6 ⁽³⁾	72.4	68.9	74.7	75 dB(A)

Note:

(1) 70 dB(A) for school and 65 dB(A) during school examination period.

(2) Impact monitoring at NM-4 was commenced on 22 May 2023.

(3) Impact monitoring at NM-5 and NM-6 was commenced on 7 September 2023.

3.6.3 Weather conditions during impact monitoring are presented in Appendix I and extracts of wind data recorded at Kai Tak Wind Station available from the Hong Kong Observatory are presented in Appendix H.

3.6.4 During the construction noise monitoring period, the influencing factors which may affect the results are summarized in Table 3.6.

Table 3.6 Influencing Factors at Noise Monitoring Stations

Monitoring Stations	Influencing Factors
NM-2	Road traffic noise, construction noise from 76 Broadcast Drive project
NM-3	Road traffic noise
NM-4	Road traffic noise
NM-4a	Road traffic noise
NM-5	Road traffic noise
NM-6	Road traffic noise

Inspection Date	Key Observations / Reminders	Follow-up Action
13 Sept 2023	1. The Contractor was reminded to clear the mud left on the haul road at Portion 3 after heavy rainfall. (Portion 3) (Reminder)	1. The mud left on the haul road at Portion 3 after heavy rainfall was cleared.
22 Sept 2023	1. The Contractor was reminded to cover the bare slope to reduce muddy surface runoff. (Portion 3) (Reminder)	1. The bare slope was covered to reduce muddy surface runoff.
27 Sept 2023	No major environmental deficiency was observed.	N/A