CONTRACT NO: SD 15/2022   Outlying Island Sewerage Stage 2 – South Lantau Sewage    Works – Environmental Team Services (2023 – 2024)   Under Environmental Permit no. EP-538/2017   annual Environmental Monitoring & Audit review Report   November 2022 to October 2023 Revision 2

Table of contents

 

1      Introduction.. 6

1.1.......... Scope of the Report 6

1.2.......... Structure of the Report 6

2.     Basic Project Information.. 8

2.1.......... Project Organization and Key Contact Personnel 8

2.2.......... Construction Programme. 8

3.     A Brief Summary of EM&A Requirements. 12

3.1.......... Monitoring Parameters. 12

3.2.......... Environmental Quality Performance Limits. 12

4.     Implementation Status. 13

4.1.......... Advice on the implementation status of environmental protection and pollution control/mitigation measures. 13

4.2.......... Environmental Mitigation Measures. 13

5.     Monitoring Results Analysis. 17

5.1.......... Noise Monitoring. 17

5.2.......... Water Quality Monitoring. 18

5.3            Ecological Impact Monitoring……………………………………………..22

5.4.......... Waste Management 22

6.     Complaints, Notification of Summons and Prosecution.. 24

7.     Comments and Recommendations. 26

8.     Conclusion.. 27

 

 

 

 

 

                                                                 

lIST OF TABLES

 

Table 2.1       Contact Details of Key Personnel

Table 2.2    Summary of submission status under EP-538/2017

Table 2.3    Summary of the current status on licences and/or permits on environmental                  protection pertinent to the Project

Table 3.1   Action and Limit Levels for Construction Noise Impact Monitoring

Table 3.2   Action and Limit Levels of Water Quality

Table 4.1       Summary of Environmental Inspections

Table 4.2     Summary of Ecological Impact Monitoring

Table 5.1       The number of noise monitoring carried out in each month during the reporting period (November 2022 to October 2023)

Table 5.2     The number of water quality monitoring carried out in each month during the          reporting period (November 2022 to October 2023)

Table 5.3     The number of water quality exceedances in each month during the reporting period (November 2022 to October 2023)

Table 5.4     Summary of Quantities of Waste Material (November 2022 to October 2023)

Table 6.1   Summary of Complaints in the Reporting Period

Table 6.2       Cumulative Statistics on Complaints

Table 6.3       Cumulative Statistics on Successful Prosecutions

 

 

lIST OF FIGUREs

 

Figure 2.1    Project Organization Chart

Figure 2.2    Master Layout Plan

Figure 2.3 Contract Layout Plan

Figure 3.1 Original location of Aquilaris sinensis

Figure 3.2 Temporary Holding Nursery

Figure 5.1   Locations of Noise Monitoring Station

Figure 5.2   Locations of Water Quality Monitoring Stations

 

 

lIST OF APPENDIces

 

Appendix 5.1    Annual Summary Waste Flow Table  

Appendix 5.2  Noise Monitoring Results and Graphical Presentations

Appendix 5.3  Marine Water Quality Monitoring Results and Graphical Presentations

Appendix 7.1    Environmental Mitigation Measures Implementation Status

 

 

EXECUTIVE SUMMARY

       i.        This is the Second Annual Environmental Monitoring and Audit (EM&A) Review Report – November 2022 to October 2023 of Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works under Environmental Permit no. EP-538/2017 (Hereafter as “the Project”).  The construction works of the Project was commenced on 3 November 2021 and the tentative completion date is Q1 2026.  The Annual EM&A Review Report presents the environmental monitoring findings and information recorded during the period of 1 November 2022 to 31 October 2023.

      ii.        In the reporting period, the principal work activities conducted are as follow:

·         Ground Excavation, sewer laying, construction of manhole at Pui O Lo Uk Tsuen, South Lantau road, Pui O Beach

·         Excavation and site formation at San Shek Wan Sewage Treatment Works (SSWSTW) and Pui O Sewage Pumping Station (POSPS)

·         HDD works at marine and SSWSTW

·         ELS works at POSPS

·         Removal works of Excavation and Lateral Support (ELS)

·         Superstructure Reinforced Concrete (RC) Works

Exceedances of Action/Limit Levels

Noise Monitoring

     iii.        Noise monitoring was conducted at eight (8) noise monitoring stations (N12a, N12b, N13, N14, N15b, N16a, N16b and N17) once per week in the reporting period.

     iv.        School examination was taken place at N17 – Bui O Public School from 14 to 16 November 2022, 27 to 28 February 2023, 1 March 2023 and 12 to 14 June 2023 in the reporting period, the limit level shall be adjusted to 65dB(A) during this period.

      v.        No action and limit level exceedances were recorded in construction noise level in the reporting period.

 

Water Quality Monitoring

     vi.        Marine-based construction works commenced on 19 April 2022. Water quality monitoring was conducted at nine (9) monitoring stations (seven impact & two control stations) three days per week in the reporting period starting from 12 April 2022. HDD casing works commenced on 30 May 2022.

    vii.        Water quality monitoring (WQM) on 1, 3 and 5 Nov 2022, 16 and 28 Jan 2023, 22 and 27 Feb 2023, 27 Mar 2023, 22 Apr, 17 Jul 2023, 1 and 8 Sep 2023, 7, 9 and 18 Oct 2023 were cancelled due to adverse weather. No substitution would be arranged for such cancellation since it is impossible to maintain the monitoring frequency as three times a week for the event of marine water quality monitoring cancellation in between time with respect to the fact that not less than 36 hours interval shall be followed for two monitoring days as required by the EM&A Manual Clause 5.1.6 (b) for the project.

   viii.        In accordance with the action level and limit level in Baseline Monitoring Report Rev. 9.2 agreed by EPD on 2 September 2022, 6 action level exceedances on turbidity, 16 action level exceedances on SS were recorded in the reporting period of 1 November 2022 to 31 October 2023.

 

Ecological Impact Monitoring

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

      x.        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 Pui O Pumping Station.

     xi.        The weekly site audit was carried out by ET include checking whether good site practices are being properly implemented by the Contractor. No unacceptable construction activities impact to the surrounding transplanted trees has been found in the reporting period of 1 November 2022 to 31 October 2023, hence, the temporary transplantation of the plant species with conservative importance is considered effective.

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

   xiii.        The retained tree (T035) Dalbergia assamica (南嶺黃檀) located within the site boundary of the Construction of San Shek Wan Sewage Treatment Works was collapsed on 2 Sep 2023 afternoon after typhoon “Saola” (Signal No. 10). No injury and significant damage were caused in the tree collapse incident. Incident report for this case was provided by the Contractor on 11 October 2023. To minimize obstruction to the public, the collapsed tree has been removed and delivered to Y Park.

 

Complaint log

   xiv.        One environmental complaint regarding the water quality at Pui O Beach was recorded on 21 December 2022 in the reporting period. Upon investigation, the works activities at Pui O Pumping Station (POPS) including land-based and marine based did not result in any unacceptable environmental impacts to the surrounding environment as reviewed with the relevant works activities and environmental requirements for the Project, and it was considered as non-project related.

 

Notifications of Any Summons and Successful Prosecutions

    xv.        No environmental notification of any summons and successful prosecution regarding the construction works was recorded in present quarter.

 

1      Introduction

1.1          Scope of the Report

1.1.1.     Lam Environmental Services Limited (LES) has been appointed to work as the Environmental Team (ET) under Environmental Permit (EP) no. EP-538/2017 to implement the Environmental Monitoring and Audit (EM&A) programme as stipulated in the EM&A Manual of the approved Environmental Impact Assessment (EIA) Report for Outlying Islands Sewerage Stage 2 - South Lantau Sewerage Works (Register No.: AEIAR-210/2017).

1.1.2.     The Annual EM&A Review Report was prepared according to Section 12.4 of the Project EM&A Manual.

1.2          Structure of the Report

Section 1        Introduction – details the scope and structure of the report

 

Section 2        Basic Project Information – a synopsis of project organization, programme contacts of key management, and a synopsis of work undertaken in the reporting period.

           

Section 3        A Brief Summary of EM&A requirements – including monitoring parameters, environmental quality performance limits (Action and Limit levels); and environmental mitigation measure, as recommended in the EIA Report.

                      

Section 4        Implementation Status – Advice on the implementation status of environmental protection and pollution control/mitigation measures, as recommended in the EIA Report and summarised in the updated implementation schedule.

 

Section 5        Monitoring Results Analysis – the trends of the monitoring parameters in present quarter; advice on the solid and liquid waste management status.

                      

Section 6        Summary of Non-Compliance (exceedances) of the environmental quality performance limits, Complaints, Notification of Summons and Successful Prosecutions

A brief review of the reasons for and the implications of non-compliance and a summary description of the actions taken and any follow-up procedures related to earlier non-compliance.

A summary record of all complaints received (written or verbal) for each media, liaison and consultation undertaken, actions and follow-up procedures taken;

A summary record of notifications of summons and successful prosecutions for breaches of the current environmental protection/pollution control legislations, including locations and nature of the breaches, investigation, follow-up actions taken and results.

                      

Section 7        Comments and Recommendations – such as effectiveness and efficiency of the mitigation measures, improvement in the EM&A programme, if any.

 

Section 8        Conclusion and Project Proponent’s contacts and hotline telephone number for the public to make enquiries

2.         Basic Project Information

2.1          Project Organization and Key Contact Personnel

2.1.1       Drainage Services Department is the overall project controllers for the Project. For the construction phase of the Project, Contractor(s), Environmental Team and Independent Environmental Checker are appointed to manage and control environmental issues.  Key personnel and contact particulars are summarised in Figure 2.1 and Table 2.1:

Table 2.1 Contact Details of Key Personnel

Party	Role	Post	Name	Contact No.	Contact Fax
Drainage Services Department (DSD)	The Engineer for the Contract	Engineer	Mr. Silas Chan	2594 7272	3104 6426
Binnies Hong Kong Limited	Engineer’s Representative	Resident Engineer	Mr. Clayton Lei Mr. Kevin Chan *	3529 3013	-
Kwan Lee – Chun Wo Joint Venture	Contractor	Site Agent	Mr. Charles Tse	9270 3384	2744 6937
		Environmental Officer	Ms. Shirley Kong	5162 5933
SMEC Hong Kong	Independent Environmental Checker (IEC)	Independent Environmental Checker (IEC)	Ms. Kitty Lee	3995 8140	3995 8101
Lam Environmental Services Limited	Environmental Team (ET)	Environmental Team Leader (ETL)	Mr. Derek Lo	2882 3939	2882 3331
Hotline telephone number for the public to make enquiries:					5560 8961

Notes:

* Engineer’s Representative change from Mr. Clayton Lei to Mr. Kevin Chan start from 1 March 2023

 

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 entire Project are divided into three contracts. Contract No. DC/2020/20 (the Contract) would have the following implementations as demonstrated in Figure 2.2.

2.2.3       The major components of the Project under Environmental Permit (EP) (EP No. EP-538/2017) comprises: (i) construction of sewage treatment works at San Shek Wan (SSWSTW) and associated submarine outfall; (ii) construction of sewage pumping station at Pui O (POSPS); (iii) village sewage works at Pui O; and (iv) trunk sewers and rising mains on carriageways.

2.2.4       The Location of works are shown in Figure 2.3.

2.3          Summary of Environmental Submissions

2.3.1       A summary of the current status on submissions and measures mentioned in Environmental Permit (EP-538/2017) are shown in Table 2.2.

Table 2.2      Summary of submission status under EP-538/2017

 

2.3.2       A summary of the current status on licences and/or permits on environmental protection pertinent to the Project is shown in Table 2.3.

Table 2.3      Summary of the current status on licences and/or permits on environmental protection pertinent to the Project

 

Permits and/or Licences	Permit. No. / Account No.	Issued Date	Valid Period & Expiry Date	Status
Notification of Works Under APCO	466408	14 Apr 2021	N/A	Valid
Wastewater Discharge Licence under Water Pollution Control Ordinance	POPS: WT00039820-2021	31 Dec 2021	31-12-2021 to 31-12-2026	Valid
	SSWSTW: WT00039636-2021	30 Dec 2021	30-12-2021 to 31-12-2026	Valid
	SSWSTW: Gravity Sewer & Raising Main: WT00042613-2022	9 Jan 2023	09-01-2023 to 31-01-2028	Valid
Billing account under Waste Disposal Ordinance	Account No.: 7040411	05 May 2021	N/A	Valid
Registration as a Chemical Waste Producer	0000-931-K3428-01	13 May 2021	N/A	Valid
Construction Noise Permit under Noise Control Ordinance for SSWSTW	GW-RS0642-22	3 Aug 2022	05-08-2022 to 02-02-2023	expired in the reporting period
	GW-RS0039-23	20 Jan 2023	03-02-2023 to 02-08-2023	expired in the reporting period
	GW-RS0657-23	9 Aug 2023	11-08-2023 to 08-02-2024	Valid
Construction Noise Permit under Noise Control Ordinance for POSPS	GW-RS0840-22	3 Oct 2022	05-10-2022 to 26-03-2023	expired in the reporting period
	GW-RS0230-23	7 Mar 2023	27-03-2023 to 26-09-2023	expired in the reporting period
	GW-RS0822-23	25 Sep 2023	27-09-2023 to 26-03-2024	Valid
Marine Dumping Permit (Dredged Sediment Requiring Type 1 – Open Sea Disposal	EP/MD/23-117	16 Oct 2023	17-10-2023 to 15-11-2023	expired in the reporting period

Note: Only include those valid or under application; fill in “N/A” for non-applicable item(s).

 

3.      A Brief Summary of EM&A Requirements

3.1  Monitoring Parameters

Noise Monitoring

3.1.1       The construction noise level shall be measured in terms of the A-weighted equivalent continuous sound pressure level (L_eq). L_eq (30min) should be used as the monitoring parameter. Supplementary information for data auditing, statistical results such as L₁₀ and L₉₀ shall also be obtained for reference.

3.1.2       For impact monitoring for construction of village sewers / rising main, noise monitoring should be undertaken on weekly basis.  One set of L_eq (30min) noise level as six consecutive L_eq (5min) between 07:00-19:00 hours on normal weekdays.

Water Quality Monitoring

3.1.3       In construction phase, the levels of dissolved oxygen (DO) (mg/L), temperature (°C), turbidity (NTU), salinity (ppt) and pH (units) should be measured in-situ while suspended solids (SS) (mg/L) is determined by laboratory analysis.

Ecological Impact Monitoring

3.1.4       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  Environmental Quality Performance Limits

Noise Monitoring

3.2.1       Noise monitoring is evaluated against Action and Limit Levels. The action and limit levels for construction noise are defined in Table 3.1 below.

Table 3.1   Action and Limit Levels for Construction Noise Impact Monitoring

 

 

 

 

Water Quality Monitoring

3.2.2       Marine-based construction works had been commenced since 19 April 2022, marine water quality monitoring was initialised since 12 April 2022. 

3.2.3       Water quality monitoring is evaluated against Action and Limit Levels. The derived Action and Limit Level proposed in Baseline Monitoring Report Rev. 9.2 was agreed by EPD on 2 September 2022. Action and Limit Levels of marine water quality monitoring have been set with reference to the derived criteria as shown in Table 3.2 below.

Table 3.2     Action and Limit Levels of Water Quality

Notes (with proposed amendments in AL/LL in underlined text):

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

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

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

D. Action Level and Limit Level with 95%-ile / 99%-ile derived from baseline data “and” 20% / 30% exceedance of control station proposed in Baseline Monitoring Report.

 

 

Ecological monitoring

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

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

3.2.6       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 (Figure 3.1) which are considered to be the plant species with conservative importance for temporarily transplanted to the nursery (Figure 3.2) at Kam Tin and eventually be transplanted to Pui O Pumping Station.

3.2.7       The retained tree (T035) Dalbergia assamica (南嶺黃檀) located within the site boundary of the Construction of San Shek Wan Sewage Treatment Works was collapsed on 2 Sep 2023 afternoon after typhoon “Saola” (Signal No. 10). No injury and significant damage were caused in the tree collapse incident. Incident report for this case was provided by the Contractor on 11 October 2023. To minimize obstruction to the public, the collapsed tree has been removed and delivered to Y Park.

 

4.      Site Inspection and Audit Reports

4.1.      In the past twelve months, total 52 nos. of joint site inspection to evaluate site environmental performance has been carried out by the RE, ET and the Contractor. Moreover, IEC attended total 12 occasion’s joint site inspection and SSEMC during the reporting period. The quantity of reminders/observations is summarized in Table 4.1.

Table 4.1  Summary of Environmental Inspections

 

4.2.      In the past twelve months, total 12 nos. of joint site inspection of holding nursery visit for transplanted trees has been carried out by the ET and the Contractor. The quantity of reminders/observations is summarized in Table 4.2.

Table 4.2  Summary of Ecological Impact Monitoring

 

 

3.1. 

5.      Monitoring Results Analysis

5.1    Noise Monitoring

5.1.1       Noise monitoring was conducted at eight (8) noise monitoring stations (N12a, N12b, N13, N14, N15b, N16a, N16b and N17) once per week in the reporting period.

5.1.2       School examination was taken place at N17 – Bui O Public School from 14 to 16 November 2022, 27 to 28 February 2023, 1 March 2023 and 12 to 14 June 2023 in the reporting period, the limit level shall be adjusted to 65dB(A) during this period.

5.1.3       Noise monitoring location plans with sensitive receivers are shown in Figure 5.1.

5.1.4       In the reporting period, the major work activities undertaken are as follows:

·         Ground Excavation, sewer laying, construction of manhole at Pui O Lo Uk Tsuen, South Lantau road, Pui O Beach

·         Excavation and site formation at San Shek Wan Sewage Treatment Works (SSWSTW) and Pui O Sewage Pumping Station (POSPS)

·         HDD works at marine and SSWSTW

·         ELS works at POSPS

·         Removal works of Excavation and Lateral Support (ELS)

·         Superstructure Reinforced Concrete (RC) Works

5.1.5       In the reporting period, total 416 of impact noise monitoring at proposed locations were carried out by the Environmental Team (ET). Detailed noise monitoring results measured in this reporting period are reviewed and summarized. Details of noise monitoring results and graphical presentation can be referred in Appendix 5.2. The number of noise monitoring carried out in each month during the reporting period are shown in Table 5.1 below, 

Table 5.1      The number of noise monitoring carried out in each month during the reporting period (November 2022 to October 2023)

 

Reporting Month	No. of Noise Monitoring
November 2022	40
December 2022	32
January 2023	40
February 2023	40
March 2023	40
April 2023	32
May 2023	32
June 2023	40
July 2023	32
August 2023	40
September 2023	32
October 2023	32

 

5.1.6       No action and limit level exceedances were recorded in construction noise level in the reporting period.

5.2    Marine Water Quality Monitoring

5.2.1       Marine Water quality monitoring involves nine (9) monitoring stations (seven impact & two control stations) three days per week in the reporting period starting from 12 April 2022.

5.2.2       Marine Water monitoring location plans with sensitive receivers are shown in Figure 5.2.

5.2.3       Water quality monitoring is evaluated against Action and Limit Levels. The derived Action and Limit Level proposed in Baseline Monitoring Report Rev. 9.2 was agreed by EPD on 2 September 2022.

5.2.4       Water quality monitoring (WQM) on 1, 3 and 5 Nov 2022, 16 and 28 Jan 2023, 22 and 27 Feb 2023, 27 Mar 2023, 22 Apr, 17 Jul 2023, 1 and 8 Sep 2023, 7, 9 and 18 Oct 2023 were cancelled due to adverse weather. No substitution would be arranged for such cancellation since it is impossible to maintain the monitoring frequency as three times a week for the event of marine water quality monitoring cancellation in between time with respect to the fact that not less than 36 hours interval shall be followed for two monitoring days as required by the EM&A Manual Clause 5.1.6 (b) for the project..

 

5.2.5       In the reporting period, total 1269 of WQM for ebb-tide and 1269 of WQM for flood-tide at proposed locations were carried out by the ET Details of marine water quality monitoring results and graphical presentation can be referred in Appendix 5.3.

 

Table 5.2      The number of water quality monitoring carried out in each month during the reporting period (November 2022 to October 2023)

Reporting Month	No. of Water Quality Monitoring
	Ebb	Flood	Total
November 2022	99	99	198
December 2022	117	117	234
January 2023	90	90	180
February 2023	90	90	180
March 2023	117	117	234
April 2023	99	99	198
May 2023	126	126	252
June 2023	117	117	234
July 2023	108	108	216
August 2023	117	117	234
September 2023	99	99	198
October 2023	90	90	180
Total	1269	1269	2538

 

5.2.6       In accordance with the action level and limit level in Baseline Monitoring Report Rev. 9.2 agreed by EPD on 2 September 2022, 6 action level exceedances on turbidity, 16 action level exceedances on SS were recorded in the reporting period of 1 November 2022 to 31 October 2023.

Table 5.3      The number of water quality exceedances in each month during the reporting period (November 2022 to October 2023)

		Parameter	DO (S&M)		DO (Bottom)		Turbidity		SS		Exceedance count
Station	Level exceeded		Mid Ebb	Mid Flood	Mid Ebb	Mid Flood	Mid Ebb	Mid Flood	Mid Ebb	Mid Flood	Mid Ebb	Mid Flood
November 2022	Derived criteria in Baseline Monitoring Report Rev. 9.2 was agreed by EPD on 2 September 2022	Action	0	0	0	0	0	0	0	1	0	1
		Limit	0	0	0	0	0	0	0	0	0	0
December 2022		Action	0	0	0	0	0	0	1	4	1	4
		Limit	0	0	0	0	0	0	0	0	0	0
January 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
February 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
March 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
April 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
May 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
June 2023		Action	0	0	0	0	0	0	1	0	1	0
		Limit	0	0	0	0	0	0	0	0	0	0
July 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
August 2023		Action	0	0	0	0	0	0	0	1	0	1
		Limit	0	0	0	0	0	0	0	0	0	0
September 2023		Action	0	0	0	0	0	0	0	0	0	0
		Limit	0	0	0	0	0	0	0	0	0	0
October 2023		Action	0	0	0	0	4	2	4	4	8	6
		Limit	0	0	0	0	0	0	0	0	0	0
Total		Action	0	0	0	0	0	0	0	0	22
		Limit	0	0	0	0	0	0	0	0	0	0

 

5.1.1       For the exceedance recorded in November 2022, 1 action level exceedance was recorded on 19 November 2022 on SS at SR15 during flood tide. In view that the water quality at monitoring stations located nearest the marine work site (SR4, SR5 and SR6) were well below Action Level and the silt curtain was in proper condition, the exceedances were possible in relation to the changes of water quality in the vicinity of the water quality monitoring station and not project related.

5.1.2       For the exceedance recorded in December 2022, 5 action level exceedances were recorded on 2, 14, 19 and 26 December 2022 on SS during ebb and flood tide. SR4 located at upstream of construction site during mid-flood such that the Action Level exceedances on SS on 19 December 2022 in general was contributed by upstream sources before entering the submarine outfall construction site. Similarly, SR9 located at upstream of construction site during mid-ebb such that the Action Level exceedances on SS on 2 December 2022 in general was contributed by upstream sources before entering the submarine outfall construction site. Co-related the monitoring dates with those days with recorded marine works activities, pilot hole drilling within the fully enclosed silt curtain on 2 December 2022, set up generator on working barge not in contact with water on 19 December 2022, no activity on 14 and 26 December 2022, the silt curtain was in proper condition and no marine dredging works were active in the reporting month. Mitigation measures including remove debris and loose material on working barge with working area was fully enclosed by silt curtain with good condition. It can be concluded that all the SS exceedances in the reporting period were possible in relation to the changes of water quality in the vicinity of the water quality monitoring station and not project related.

5.1.3       For the exceedance recorded in June 2023, 1 action level exceedances at SR4 was recorded on 12 June 2023 on SS during ebb tide. Co-related the monitoring dates with those days with recorded marine works activities, no marine dredging works were active during the reporting period. Pilot hole drilling on 12 June 2023 within the fully enclosed silt curtain started from 09:20 to 09:36 and 16:00 to 18:40. Water quality monitoring at SR4 was conducted at 07:59 to 08:02 which was before the pilot hole drilling works. No exceedance was recorded on same day during flood tide at 13:12 to 13:15 and in the subsequent monitoring on 14 June 2023 both ebb and flood tide. Reviewed the overall work situation and the mitigation measures was implemented by the Contractor, it can be concluded that the SS exceedances at SR4 was possibly due to natural runoff from streams to the sea or sudden changed of water body as a result of frequent rainfall as recorded in the reporting month (Amber rainstorm warning signal recorded on 10 June 2023, heavy showers recorded on 11 June 2023 and rainstorm recorded during water quality monitoring on 12 June 2023).

5.1.4       For the exceedances recorded in August 2023, 1 action level exceedance at SR4 was recorded on 9 August 2023 on SS. Co-related the monitoring dates with those days with recorded marine works activities, no marine dredging works were active during the reporting month. No marine works during 17 July 2023 to 11 Aug 2023 due to the silt curtain was found broken after Typhoon No. 8 on 17 July 2023 and repaired on 12 August 2023. No exceedance was recorded on same day during ebb tide from 07:13 to 07:16 and in the subsequent monitoring on 11 August 2023 both ebb and flood tide. Reviewed the overall work situation and the mitigation measures was implemented by the Contractor, it can be concluded that the SS exceedances at SR4 was possibly due to natural runoff from streams to the sea or sudden changed of water body.

5.1.5       For the exceedances recorded in October 2023, 3 action level exceedances on turbidity and SS during ebb tide on 20 October 2023 were recorded; 2 action level exceedances on turbidity and 4 action level exceedances on SS during flood tide were recorded on 23 October 2023, 1 action level exceedances on turbidity and SS during ebb tide was recorded on 23 October 2023. Co-related the monitoring dates with those days with recorded marine works activities, no marine dredging works were active during the reporting month. Smoothening works within enclosed silt curtain on 20 October 2023. Higher turbidity was recorded (>10 NTU) at all stations including control stations during ebb and flood tide. No exceedances was recorded in the subsequent monitoring at these stations on 23 Oct 2023, No marine works conducted on 23 October 2023. No exceedances was recorded in the subsequent monitoring at these stations on 25 Oct 2023. Reviewed the overall work situation and the mitigation measures was implemented by the Contractor, it can be concluded that the turbidity and SS exceedances was possibly due to natural runoff from streams to the sea or sudden change of water body.

 

5.1.6       Marine water quality monitoring results measured in this reporting period are reviewed and summarized. Details of marine water quality monitoring results and graphical presentation can be referred in Appendix 5.3.

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5.2    Ecological Impact Monitoring

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

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

5.2.3       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 Pui O Pumping Station.

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5.3       Waste Management

5.3.1       The quantities of waste for disposal in present period are summarized in Table 5.4. The Annual Summary Waste Flow Table is shown in Appendix 5.1.

 

Table 5.4 Summary of Quantities of Waste Material (November 2022 to October 2023)

Waste Type	Quantity for reporting period	Cumulative Quantity-to-Date
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)	5.22	13.78
Metals (in ‘000kg)	5.95	7.52
Paper / Cardboard Packing (in ‘000kg)	0.29	0.52
Plastics (in ‘000kg)	0.04	0.058
Chemical Wastes (in ‘000kg)	0	0
General Refuses (in ‘000kg)	149.45	538.58
Remark: Summary of waste disposal has been updated in this annual report.

 

6.      Complaints, Notification of Summons and Prosecution

6.        

6.0.        

6.1.1       One environmental complaint regarding the water quality at Pui O Beach was recorded in the reporting period. Upon investigation, the works activities at Pui O Pumping Station (POPS) including land-based and marine based did not result in any unacceptable environmental impacts to the surrounding environment as reviewed with the relevant works activities and environmental requirements for the Project, and it was considered as non-project related..

Table 6.1      Summary of Complaints in the Reporting Period

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

6.1.3       Cumulative statistic on complaints and successful prosecutions are summarized in Table 6.2 and Table 6.3 respectively.

Table 6.2 Cumulative Statistics on Complaints

Reporting Period	No. of Complaints
November 2022 - October 2023	1
Project commencement to the end of last reporting period	2
Total	2

 

Table 6.3 Cumulative Statistics on Successful Prosecutions

Environmental Parameters	Cumulative No. Brought Forward	No. of Successful Prosecutions this month (Offence Date)	Cumulative No. Project-to-Date
Air	-	0	0
Noise	-	0	0
Water	-	0	0
Waste	-	0	0
Other	-	0	0
Total	-	0	0

 

7.      Comments and Recommendations

7.        

7.0.        

7.1.1       The environmental mitigation measures that recommended in the Implementation Status of Recommended Mitigation Measure in the Project EM&A Manual covered the issues of Air Quality, Noise, Water Quality, Ecological Impact, Waste Management Implication, Landscape & Visual and Cultural Heritage and presented in Appendix 7.1.

7.1.2       The recommended mitigation measures for the reporting period are listed below:

·         Proper water pollution control measures to be taken to prevent untreated effluent discharge from site work

·         Vehicle wheel-washing and body washing facilities should be provided at the site entrance;Adopt temporary drainage and sediment control facilities on Site;

·         Adopt surface drainage and sediment control facilities for sewage installation in village and public roads

·         Silt curtains should be installed to surround the marine dredging area in accordance with Silt Curtain Deployment Plan.

·         Dust control during dust generating works;

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

·         Tree protection works within the Project Site;

·         Proper waste handling, recycling and storage;

·         Ensure the transplanting of the trees including Aquilaris sinensis and their establishment are not affected by any unacceptable construction works;

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

·         Provide caring measures for the health, form and structural conditions for transplant trees including Aquilaris sinensis in holding nursery;

·         Fully implement tree preservation works on site and holding nursery to ensure compliance of relevant legislation and guidelines stated in EM&A Manual.

·         Implementation of noise pollution control including use of QPME in accordance with Construction Noise Mitigation Plan;

·         Regular water spraying on drilling, exposed area and excavation works for dust control;

·         To inspect the condition of silt curtains on regular basis, and after adverse weather including any rainstorms and typhoons in wet season.

The implemented mitigation measures are considered effective.

 

 

 

8.      Conclusion

8.1  Noise Monitoring.

8.1.1       Noise monitoring was conducted at eight (8) noise monitoring stations (N12a, N12b, N13, N14, N15b, N16a, N16b and N17) once per week in the reporting period.

8.1.2       No action or limit level exceedance was recorded in construction noise level in this present period.

 

8.2  Water Quality Monitoring

8.2.1       Marine-based construction works has been commenced since 19 April 2022, marine water monitoring was initialised since 12 April 2022. 

8.2.2       Water quality monitoring (WQM) on 1, 3 and 5 Nov 2022, 16 and 28 Jan 2023, 22 and 27 Feb 2023, 27 Mar 2023, 22 Apr, 17 Jul 2023, 1 and 8 Sep 2023, 7, 9 and 18 Oct 2023 were cancelled due to adverse weather.

8.2.3       In accordance with the action level and limit level in Baseline Monitoring Report Rev. 9.2 agreed by EPD on 2 September 2022, 6 action level exceedances on turbidity, 16 action level exceedances on SS were recorded in the reporting period of 1 November 2022 to 31 October 2023.

 

8.3  Ecological Impact Monitoring

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

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

8.3.3       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 Pui O Pumping Station.

8.3.4       The retained tree (T035) Dalbergia assamica (南嶺黃檀) located within the site boundary of the Construction of San Shek Wan Sewage Treatment Works was collapsed on 2 Sep 2023 afternoon after typhoon “Saola” (Signal No. 10). No injury and significant damage were caused in the tree collapse incident. Incident report for this case was provided by the Contractor on 11 October 2023. To minimize obstruction to the public, the collapsed tree has been removed and delivered to Y Park.

 

8.4  Review of the Reasons for and the Implications of Non-compliance

8.4.1       No environmental non-compliance was recorded in present period.

 

8.5  Summary of action taken in the event of and follow-up on non-compliance

8.5.1       There was no particular action taken since no non-compliance was recorded in present period.