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
 
Monthly Environmental Monitoring & Audit Report
 
Septermber 2023
revision 2


CLIENTS:

PREPARED BY:

 

 

Drainage Services Department

 

 

 

Lam Environmental Services Limited

 

19/F, Remex Centre,

42 Wong Chuk Hang Road,

Hong Kong

 

 

 

Telephone: (852) 2882-3939

Facsimile: (852) 2882-3331

E-mail: info@lamenviro.com

Website: http://www.lamenviro.com

 

 

 

 

 

Certified by:



 

 

 

 

_______________________________

Derek Lo

Environmental Team Leader

 

 

 

DATE:

 

 

13 October 2023

 

 


Table of contents

1............. Introduction.. 6

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

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

2.............. Basic project Information and Environmental Status. 8

2.1.......... Basic Project Information.. 8

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

2.3.......... Works undertaken during the month.. 9

2.4.......... Drawing showing the project area, environmental sensitive receivers and monitoring locations. 9

3............. Implementation Status. 9

3.1.......... Advice on the implementation status of environmental protection and pollution control/mitigation measures. 9

3.2.......... Environmental Mitigation Measures. 10

3.3.......... Environmental monitoring requirements and contractual requirements. 10

3.4.......... Site Inspection and Audit Reports. 11

4............. Monitoring Results. 13

4.1.......... Noise Monitoring. 13

4.2.......... Water Quality Monitoring. 16

4.3.......... Ecology. 20

4.4.......... Waste Management 21

5............. Complaints, Notification of Summons and Prosecution.. 23

6............. Future Key Issues. 25

7............. Conclusion.. 26

7.1.......... Noise Monitoring. 26

7.2.......... Water Quality Monitoring. 26

7.3.......... Ecological Impact Monitoring. 26

7.4.......... Review of the Reasons for and the Implications of Non-compliance. 27

7.5.......... Summary of action taken in the event of and follow-up on non-compliance. 27

 

 

           

lIST OF TABLES

 

Table 3.1       Summary of submission status under EP-538/2017

Table 3.2       Summary of the current status on licences and/or permits on environmental protection pertinent to the Project

Table 3.3       Summary of Environmental Inspections

Table 4.1       Noise Monitoring Equipment

Table 4.2       Noise Monitoring Station

Table 4.3       Water Quality Monitoring Equipment

Table 4.4     Marine Water Quality Stations for Water Quality Monitoring

Table 4.5     Action and Limit Levels of Water Quality

Table 4.6     Summary of Marine Water Quality Exceedances

Table 4.7       Summary of Quantities of Waste Material

Table 5.1       Cumulative Statistics on Complaints

Table 5.2       Summary of Complaints

Table 5.3       Cumulative Statistics on Successful Prosecutions

Table 6.1       Construction Activities and Recommended Mitigation Measures in Coming Reporting 3 Months

 

 

lIST OF FIGUREs

 

Figure 2.1    Master Layout Plan

Figure 2.2    Contract Layout Plan

Figure 2.3   Locations of Noise Monitoring Station

Figure 2.4   Locations of Water Quality Monitoring Stations

Figure 2.5    Mark up Figure 5.4i extracted from approved EIA Report (AEIAR-210/2017)

Figure 2.6    Location Plan for Temporary Holding Nursery

 

 

lIST OF APPENDIces

 

Appendix 4.1    Copies of Calibration Certificates

Appendix 4.2    Impact Monitoring Schedule for Reporting Month and Next Month

Appendix 4.3    Noise Monitoring Results and Graphical Presentations

Appendix 4.4    Marine Water Quality Monitoring Results and Graphical Presentations

Appendix 4.5    Monthly Summary Waste Flow Table

Appendix 6.1    3 Months Rolling Programme


 

EXECUTIVE SUMMARY

       i.        This is the Monthly Environmental Monitoring and Audit (EM&A) Report – September 2023 for the 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.  This Monthly EM&A Report presents the environmental monitoring findings and information recorded during the period of 1 to 30 September 2023.  The cut-off date of reporting is at the end of each reporting month.

      ii.        In the reporting period, the principal work activities undertaken are as follows:

·       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)

·       Horizontal Directional Drilling (HDD) works at marine and SSWSTW

·       Removal works of Excavation and Lateral Support (ELS)

·       Excavation and Lateral Support (ELS) works

·       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.        No school examination was taken place at N17 – Bui O Public School in the reporting period.

      v.        No Action/Limit Level exceedances were recorded in this reporting period.

 

Water Quality Monitoring

     vi.        Water quality monitoring (WQM) had been commenced on 12 April 2022 the designated monitoring stations three days per week with respect to marine-based construction works commenced on 19 April 2022. HDD casing works commenced on 30 May 2022.

    vii.        Water quality monitoring on 1 Sep 2023 and 8 Sep 2023 were cancelled due to Typhoon Signal no. 8 and Black Rainstorm Signal respectively. 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, no action level and limit level exceedances were recorded in the reporting month.

 

Ecological Impact Monitoring

     ix.        Transplanting of the trees of 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 Aquileia 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.

    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. To minimize obstruction to the public, the trees were subsequently sawn and removed. Incident report for this case would be provided by the Contractor.

 

Complaint log

   xiv.        No environmental complaint regarding the construction works was recorded in the reporting period.

 

Notifications of Any Summons and Successful Prosecutions

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

 

Reporting Changes

   xvi.        There are no particular reporting changes.

Future Key Issues

  xvii.        In coming reporting 3 months, the scheduled construction activities are listed as follows:

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

·          HDD works at marine and SSWSTW

·          Site formation works

·          Drilling works

·          Excavation works

·          ELS works

·          Superstructure RC Works

·          Removal works of ELS

 

 xviii.        Key construction activities for the next three months with the recommended mitigation measures to be implemented are presented as follows:

Key Construction Works

Recommended Mitigation Measures

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

·         HDD works at marine and SSWSTW

·         Site formation works

·         Drilling works

·         Excavation works

·         ELS works

·         Superstructure RC Works

·         Removal works of ELS

 

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

·         Dust control during dust generating works;

·         Silt curtain should be maintained in good condition;

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

·         Adopt temporary drainage and sediment control facilities on Site;

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

·         Regular water spraying on excavation works for dust control; and

·         Proper waste handling, recycling and storage.

 

 


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 the Outlying Islands Sewerage Stage 2 – South Lantau Sewerage Works (Register No.: AEIAR-210/2017).

1.1.2.     In accordance with Clause 3.4 stated in EP-538/2017, 4 hard copies and 1 electronic copy of Monthly EM&A Report shall be submitted to the Director within 2 weeks after the end of each reporting month.

1.1.3.     According to Section 12.2 of the Project EM&A Manual, the Monthly EM&A Report should be submitted within 10 working days of the end of each reporting month, with the first report due in the month after construction commences.

 

1.2          Structure of the Report

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

Section 2        Basic project Information and Environmental Status – summarizes project organization and key personnel contact, construction programme and works undertaken for the month. Construction programme, works undertaken during the month with illustrations, drawing showing the project area, environmental sensitive receivers and monitoring locations.

Section 3        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 4        Monitoring Results – summarizes the monitoring results obtained in the reporting period, including monitoring methodology, name of laboratory and equipment used and calibration details, parameters monitored, monitoring locations (and depth), monitoring date, frequency, and duration.

Section 5        Report on Complaints, Notification of Summons and Successful Prosecutions – summarizes:

                       Record of all complaints received (written or verbal) for each media, including locations and nature of complaints investigation, liaison and consultation undertaken, actions and follow-up procedures taken, results and 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, results and summary;

 

                       Review of the reasons for and the implications of non-compliance, complaints, summons and prosecutions including review of pollution sources and working procedures; and

                       Description of the actions taken in the event of non-compliance and deficiency reporting and any follow-up procedures related to non-compliance.

Section 6        Future Key Issues – An account of the future key issues as reviewed from the works programme and work method statements.

Section 7        Conclusion


 

2                    Basic project Information and Environmental Status

2.1          Basic Project Information

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 summarized in 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. 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

 

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 2.1.

2.2.3.     The major components of the Contract under Environmental Permit (EP) (EP No. EP-538/2017) comprises: (i) construction of secondary sewage treatment works (STW) at San Shek Wan in South Lantau; (ii) construction of sewage pumping station (SPS) at Pui O, San Shek Wan, Cheung Sha and Cheung Fu Street; (iii) construction of about 1.4 kilometres (km) of submarine outfall with a diameter of 350 millimetres (mm) for the disposal of treated effluent from the STW at San Shek Wan; (iv) construction of about 10.1 km of gravity sewers with diameters ranging from 150 mm to 375 mm along South Lantau Road and Chi Ma Wan road and at Pui O; and (v) construction of about 3.1 km twin rising mains with a diameter of 200 mm to 250 mm along South Lantau Road and Chi Ma Wan Road.

2.2.4.     The performance of the environmental management system of the reporting period was generally satisfied. Mitigation measures according to the environmental mitigation implementation schedule and the EIA were generally implemented by the Contractor. Hence, the EM&A programme was considered effective and shall be maintained.

 

2.3          Works undertaken during the month

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

·       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)

·       Horizontal Directional Drilling (HDD) works at marine and SSWSTW

·       Removal works of Excavation and Lateral Support (ELS)

·       Excavation and Lateral Support (ELS) works

·       Superstructure Reinforced Concrete (RC) Works

The locations of works are shown in Figure 2.2.

2.4          Drawing showing the project area, environmental sensitive receivers and monitoring locations

2.4.1.     Noise and water monitoring location plans with sensitive receivers are shown in Figure 2.3 and Figure 2.4.

 

3              Implementation Status

3.1          Advice on the implementation status of environmental protection and pollution control/mitigation measures

3.1.1.     Mitigation measures according to the environmental mitigation implementation schedule in Annex A of EM&A Manual were generally implemented by the Contractor. Hence, the EM&A programme was considered effective and shall be maintained.

 

3.2          Environmental Mitigation Measures

3.2.1.     Environmental mitigation measures mentioned the EIA Report were weekly reviewed and recorded in Weekly Environmental Site Audit Checklist. Also, a summary of the current status on submissions and measures mentioned in Environmental Permit (EP-538/2017) are shown in Table 3.1.

 

Table 3.1     Summary of submission status under EP-538/2017

EP Condition

Submission

Date of Latest Submission to EPD^ / EPD Approval#

Condition 2.10

Waste Management Plan (Rev. 5)

(electronic copy)

4 April 2022#

Condition 2.11

Submission of Preservation and/or Transplantation Plan for Plant Species of Conservation Importance (Rev. 23)

9 September 2022#

Condition 2.12

Submission of Compensatory Woodland Planting Plan (Rev. 23)

15 May 2023^

Condition 2.13

Silt Curtain Deployment Plan (Rev. 11)

1 June 2022#

Condition 2.14

Landscape Mitigation Plan

To be confirmed

Condition 2.15

Construction Noise Mitigation Plan (Rev. 20)

4 August 2022#

 

3.3          Environmental monitoring requirements and contractual requirements

3.3.1.     A summary of the current status on licences and/or permits on environmental protection pertinent to the Project is shown in Table 3.2.

 

Table 3.2     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

SSWSTW:

WT00039636-2021

30 Dec 2021

30-12-2021 to 31-12-2026

Valid

POPS:

WT00039820-2021

31 Dec 2021

31-12-2021 to 31-12-2026

Valid

SSWSTW: Gravity Sewer & Raising Main:

WT00042613-2022

09 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-RS0657-23

9 Aug 2023

11-08-2023 to 08-02-2024

Valid

Construction Noise Permit under Noise Control Ordinance for POSPS

GW-RS0230-23

7 Mar 2023

27-03-2023 to 26-09-2023

Expired on 26 Sep 2023

GW-RS0822-23

25 Sep 2023

27-09-2023 to 26-03-2024

Valid

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

 

3.4          Site Inspection and Audit Reports

3.4.1.     Within this reporting month, weekly environmental site inspections were conducted on 05, 12, 18 and 26 September 2023. IEC attended the SSEMC meeting held on 18 September 2023. Holding nursery visit for transplanted trees on 21 September 2023.

3.4.2.     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 month are listed below in Table 3.3.

 


 

Table 3.3          Summary of Environmental Inspections

 

Inspection Date

Reminder and Recommendations

Close-out Date / Status

05 September 2023

Pui O Sewage Pumping Station-

1.       Stagnant water in the Drip tray should be removed regularly

2.       Exposed surface should be well covered

3.       Drip tray should be provided to chemical container

Remainder:

-       Retained tree (T035, Dalbergila balansae 南嶺黃檀) at the site entrance/exit of POSPS was fallen

after Typhoon Saola, Contractor is reminded to report to relevant parties accordingly

 

Rectified on 15 Sep 2023

 

Incident report for T035 was provided on 28 Sep 2023

12 September 2023

Pui O Sewage Pumping Station-

1.          Housekeeping on site should be enhanced.

Rectified on 14 Sep 2023

18 September 2023

Pui O Sewage Pumping Station & San Shek Wan Sewage Treatment Works(SSWSTW)-

1.     Drip trays shall be provided to chemical containers

2.     Tree protection zones shall be established in order to prevent the trees from being damaged during construction.

Remainder:

Pui O Beach Road Rising Mains

-       Noise mitigation measures shall be enhanced to avoid noise nuisance to nearby school

 

 

Rectified on 22 Sep 2023

26 September 2023

Pui O Sewage Pumping Station (POSPS)

1.     Tree label should be provided to the retained trees within the site area.

Rectified on 27 Sep 2023


 

4              Monitoring Results

4.1          Noise Monitoring

Monitoring methodology

4.1.1      Monitoring Procedure

(a)           The impact noise monitoring should be carried out at all the designated monitoring stations when there are project-related construction activities undertaken within a radius of 300m from the monitoring stations.

(b)           The monitoring station shall normally be at a point 1m from the exterior of the sensitive receiver’s building façade and be at a position 1.2m above the ground.

(c)           Façade measurements were made at the monitoring locations. For free-field     measurement, a correction factor of +3 dB (A) would be applied.

(d)           The battery condition was checked to ensure the correct functioning of the meter.

(e)           Parameters such as frequency weighting, the time weighting and the measurement time were set as follows:

(f)            Frequency weighting: A, Time weighting: Fast, Measurement time set: continuous 5 mins

(g)           Prior and after to the noise measurement, the meter was checked using the acoustic calibrator for 94dB (A) at 1000 Hz. If the difference in the calibration level before and after measurement was more than ±1.0 dB (A), the measurement would be considered invalid and repeat of noise measurement would be required after re-calibration or repair of the equipment.

(h)           Noise measurements will be made in accordance with standard acoustical principles and shall not be made in fog, rain, wind with a steady speed exceeding 5m/s or wind with gusts exceeding 10m/s. The wind speed shall be checked with a portable wind speed meter capable of measuring the wind speed in m/s.

 

name of laboratory and equipment used and calibration details

4.1.2      Noise monitoring was performed using sound level meter at the designated monitoring locations. The sound level meters shall comply with the International Electrotechnical Commission Publications 651:1979 (Type 1) and 804:1985 (Type 1) specifications. Acoustic calibrator shall be deployed to check the sound level meters at a known sound pressure level. Brand and model of the equipment is given in Table 4.1.

 

Table 4.1     Noise Monitoring Equipment

Equipment

Brand and Model

Series Number

Integrated Sound Level Meter

Larson Davis LxT1

0005062

Acoustic Calibrator

Larson Davis CAL200

13437

 

4.1.3      The calibration certificates of the noise monitoring equipment are attached in Appendix 4.1.

 

4.1.4      Calibration Details

(a)           The microphone head of the sound level meter was cleaned with soft cloth at regular intervals.

(b)           The sound level meter and calibrator were calibrated at yearly intervals.

 

Parameters monitored

4.1.5      The construction noise level shall be measured in terms of the A-weighted equivalent continuous sound pressure level (Leq). Leq(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.

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

 

Monitoring Stations

4.1.7      The noise monitoring stations for the Project are listed and shown in Table 4.2, impact 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 month.

 

Table 4.2     Noise Monitoring Station

Monitoring Station ID (1)

Monitoring Location

Measurement Type

Level

(in terms of

no. of floor)

N01a

Shui Hau Village

Free-Field

G/F

N01c

Shui Hau Village

Free-Field

G/F

N03a

Tong Fuk Village

Free-Field

G/F

N05a

Residences at Cheung Fu Street

Free-Field

G/F

N07

Government Holiday Bungalows

Free-Field

G/F

N08

Cheung Sha Ha Tsuen

Free-Field

G/F

N10

Cheung Sha Sheung Tsuen

Façade

G/F

N11b

San Shek Wan – Ming Garden

Free-Field

G/F

N12a

Lo Uk Tsuen

Free-Field

G/F

N12b

Lo Uk Tsuen

Façade

G/F

N13

Pui O San Wai Tsuen

Façade

G/F

N14

South Lantau Community Centre

Free-Field

G/F

N15b

Pui O Lo Wai Tsuen

Façade

G/F

N16a

Residences at Ham Tin

Free-Field

G/F

N16b

Residences at Ham Tin

Free-Field

G/F

N17

Bui O Public School

Façade

R/F

Remarks (1): Fine adjustment of noise monitoring stations at all locations was proposed as per EP Condition 3.1.

 

Monitoring date, time, Frequency and Duration

4.1.8      For daytime construction work on normal weekdays, monitoring of Leq(30min) should be carried out at each station at 0700-1900 hours on normal weekdays at a frequency of once a week.  Impact monitoring schedule can be referred to Appendix 4.2.

 

Noise Monitoring Results

4.1.9      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 4.3.

4.1.10    No school examination was taken place at N17 – Bui O Public School in the reporting period.

4.1.11    No action or limit level exceedance was recorded in construction noise level in this reporting period.

 


4.2          Water Quality Monitoring

Monitoring Methodology

4.2.1      Monitoring Procedure

(a)           The condition near the monitoring stations shall be observed and recorded on the data log sheet.

(b)           Check of sensors and electrodes with certified standard solutions before each use.

(c)           Wet bulb calibration for a DO meter should be carried out before measurement.

(d)           Water depth should be recorded by detector before sampling.

(e)           Sample would be taken using bucket sampler at surface level.

(f)            Transfer the sampled water carefully into cleaned water bottles (2x 1000ml) provided by the laboratory at the spot after the collection of the water sample for the subsequent laboratory Suspended Solid testing.

(g)           Transfer the sampled water from the bucket sampler to the rinsed water container for in-situ measurement (In case of the in-situ measurement cannot be carried at spot due to safety and adverse weather condition, sampled water from the bucket sampler will be transfer to cleaned water bottles provided by laboratory. Then, In-situ measurement will be conducted at a safe location which sampled water inside cleaned water bottle will be transfer to the rinsed water container for in-situ measurement) In-situ measurement shall be measured in duplicate.

(h)           Parameters including Water Temperature (°C), pH (units), Salinity (ppt), DO (mg/L), DO saturation (%) will be measured by the Multifunctional Meter and Turbidity (NTU) will be measured by turbid meter. (Water Temperature and Salinity will be measured as reference parameters)

(i)             Record the result on the data log sheet and record any special finding during / after in-situ measurement.

(j)             The water sample bottles will be stored in a cool box (at cooled to 4°C  without being frozen), which shall be delivered to HOKLAS laboratory (ALS Technichem (HK) Pty Ltd) for further testing to determine the level of SS.

 

Name of laboratory and equipment used and calibration details

Laboratory Measurement / Analysis

4.2.2      Analysis of suspended solids will be carried out in a HOKLAS accredited laboratory, which is ALS Technichem (HK) Pty Ltd.

 

equipment used

Dissolved Oxygen, pH And Temperature Measuring Equipment

4.2.3      Multifunctional Meter and Turbid Meter are used at each designated monitoring station. They are capable of measuring:

 

(a)           a dissolved oxygen level in the range of 0-20mg/L and 0-200% saturation (Detection Limit: 0.1mg/L)

(b)           a temperature of 0-45 degree Celsius (Detection Limit: 0.1 degree Celsius)

(c)           turbidity level between 0-1000NTU (Detection Limit: 0.1NTU)

(d)           salinity in the range of 0-40ppt (Detection Limit: 0.1ppt)

(e)           pH value in range of 0.0 – 14.0 (Detection Limit: 0.1units)

 

Other monitoring equipment namely water depth meter, water current meter, dGPS positioning device, water sampler listed below were also deployed,

(a)           Water depth meter (Range: 0.6 -100m, Resolution: 0.1m)

(b)           Water current meter (Range: 0-360o, Detection Limit: 1mm/s)

(c)           dGPS positioning device (Resolution: Horizontal: 0.25m; Vertical: 0.50 m )

(d)           Water sampler (Horizontal discrete type, Capacity: 2.2L)

 

Sampler Container and Storage

4.2.4      A water sampler, Water samples for suspended solids measurement should be collected in high-density polythene bottles, packed in ice (cooled to 4°C without being frozen), and delivered to ALS Technichem (HK) Pty Ltd. as soon as possible after collection for analysis.

 

Water Depth Detector

4.2.5      A portable, battery-operated echo sounder shall be used for the determination of water depth at each designated monitoring station. This unit can either be handheld or affixed to the bottom of the workboat, if the same vessel is to be used throughout the monitoring programme.

 

calibration details

4.2.6      Maintenance and Calibration

(a)           The responses of sensors and electrodes of the water quality monitoring equipment were cleaned and checked at regular intervals.

(b)           DO meter (Multifunctional Meter) and turbid meter was certified by a laboratory accredited under HOKLAS or any other international accreditation scheme, and subsequently re-calibrated at three monthly intervals.

 

4.2.7      Brand and model of the equipment are given in Table 4.3.

 Table 4.3   Water Quality Monitoring Equipment

 

Equipment

Brand and model

Series Number

Multifunctional Meter

Sonde YSI Professional Plus

20M100002 / 20M101455

Turbid meter

Xin Rui WGZ-3B

2209074

 

 

Calibration certificates of the water quality monitoring equipment are attached in Appendix 4.1.

 

Parameters monitored

4.2.8      In construction phase, the levels of dissolved oxygen (DO), temperature, turbidity and salinity should be measured in situ while suspended solids (SS) is determined by laboratory analysis.

 

MONITORING STATIONS

4.2.9      Water quality monitoring involves 9 monitoring stations. The locations of water quality monitoring station are shown in Table 4.4.

Table 4.4    Marine Water Quality Stations for Water Quality Monitoring

Station

Description

Easting

Northing

CE

Upstream control station at ebb tide

810838

807538

CF

Upstream control station at flood tide

815886

808081

SR4 (1)

Ecological Sensitive Receiver (Coral Communities) at Pui O Wan

814938

810975

SR5

Ecological Sensitive Receiver (Coral Communities) at Pui O Wan

814326

810540

SR6

Gazetted Bathing Beach at Lower Cheung Sha

810553

810475

SR9 (1)

Ecological Important Stream at Tong Fuk

811325

809787

SR10

Secondary Contact Recreational Zones at South Lantau

810561

809494

SR12 (1)

Proposed Special Site of Scientific Interest (SSSI) at Shui Hau Wan

810359

808989

SR15

Gazetted Bathing Beach at Pui O and Ecologically Important Stream at Pui O

816037

810722

Remarks (1): Fine adjustment of water quality monitoring stations at SR4, SR9 and SR12 was proposed as per EP Condition 3.1, and baseline monitoring was conducted at corresponding fine adjusted locations.

 

Monitoring date, time, Frequency and Duration

4.2.10    Water quality monitoring had been commenced on 12 April 2022 the designated monitoring stations three days per week with respect to marine-based construction works commenced on 19 April 2022. HDD casing works commenced on 30 May 2022.

4.2.11    To support water quality monitoring, the silt curtain deployment plan has minor updates to include an additional brand of geosynthetic material as alternative for selection and adopt underwater robot for inspecting condition of silt curtain.

4.2.12    The levels of dissolved oxygen (DO), temperature, turbidity and salinity were measured in situ while suspended solids (SS) is determined by laboratory analysis at all the monitoring stations in Table 4.4 three times a week. Impact monitoring schedule can be referred to Appendix 4.2.

4.2.13    In association with the water quality parameters, other relevant data shall also be recorded, such as monitoring location / position, time, water temperature, DO saturation, weather conditions, and any special phenomena underway near the monitoring station.

4.2.14    Impact Monitoring shall be carried out three days per week, at mid-flood and mid-ebb tides (within ± 1.75 hour of the predicted time). The interval between two sets of monitoring shall not be less than 36 hours. The monitoring period should avoid concurrent marine project in the vicinity.

4.2.15    The sampling frequency of at least three days per week should be undertaken. Upon completion of the construction works, the monitoring exercise at the designated monitoring locations should be continued for four weeks in the same manner as the impact monitoring. In case exceedance of Action/Limit Level is recorded, the frequency shall be increased as per the Event and Action Plan.

4.2.16    To ensure the robustness of in-situ measurement, parameters shall be measured in duplicate. In case the difference between duplicates is larger than 25%, a third set of measurement shall be carried out.

Monitoring Results

4.2.17    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 4.4

4.2.18    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 4.5 below for reference.

Table 4.5    Action and Limit Levels of Water Quality

Parameters

Action Level

Limit Level

Construction Phase Marine Water Monitoring - derived criteria

DO in mg/L B

Surface and Middle: 5.8 mg/L

Bottom: 5.9 mg/L

Surface and Middle: 4 mg/L

Bottom: 2 mg/L

Turbidity in NTU

(Depth-averaged A) C

14.4 NTU and

20% exceedance of value at any impact station compared with corresponding data from control station D

23.5 NTU and

30% exceedance of value at any impact station compared with corresponding data from control station D

SS in mg/L

(Depth-averaged AC

13.1 mg/L and

20% exceedance of value at any impact station compared with corresponding data from control station D

30.4 mg/L and

30% exceedance of value at any impact station compared with corresponding data from control station D

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.

 

4.2.19    Number of exceedances recorded during the reporting month are summarized in Table 4.6.

Table 4.6    Summary of Marine Water Quality Exceedances

 

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

SR4

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR5

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR6

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR9

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR10

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR12

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

SR15

Action

/

/

/

/

/

/

/

/

0

0

 

Limit

/

/

/

/

/

/

/

/

0

0

Total

Action

0

0

0

0

0

0

0

0

0

 

Limit

0

0

0

0

0

0

0

0

0

 

4.2.20    Water quality monitoring on 1 Sep 2023 and 8 Sep 2023 were cancelled due to Typhoon Signal no. 8 and Black Rainstorm Signal respectively. 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.

4.2.21    In accordance with the action level and limit level in Baseline Monitoring Report Rev. 9.2 agreed by EPD on 2 September 2022, no action level and limit level exceedances were recorded in the reporting month.

 

4.3          Ecology

MONITORING METHODOLOGY

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

4.3.2      Impact monitoring of the transplanted Aquilaris sinensis at holding nursery and one retain tree of Aquilaris sinensis in SSWSTW Project Site, establishment and after-establishment caring measures of the compensatory mixed woodland to ensure the affected tree would not be affected by any unacceptable construction works. The trees would be treated with establishment works immediately after transplanting.

 

PARAMETERS MONITORED

4.3.3      The extent of the work site boundaries should be checked by the ET during the weekly site audit.  Any disturbance by the Contractor outside the works area especially any damage to the vegetation and surrounding habitats outside the Project area shall be reported to ER and IEC.

4.3.4      To identify any unacceptable construction works for the trees of Aquilaris sinensis during transplanting, establishment and after-establishment caring measures of the compensatory mixed woodland.

 

MONITORING LOCATION

4.3.5       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 2.5) which are considered to be the plant species with conservative importance for temporarily transplanted to the nursery (Figure 2.6) at Kam Tin and eventually be transplanted to Pui O Pumping Station.

 

MONITORING DATE, TIME, FREQUENCY AND DURATION

4.3.6      The recommended good site practices to be audited once every week as part of the site audit programme. The weekly site audit to be carried out by the ET includes checking whether good site practices are being properly implemented by the Contractor. Results are recorded in Weekly Environmental Site Audit Checklist.

4.3.7       Monitoring programme for post-transplantation was conducted on 21 September 2023 once per month.

 

MONITORING RESULTS

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

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

4.3.10    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. To minimize obstruction to the public, the trees were subsequently sawn and removed. Incident report for this case would be provided by the Contractor.

4.3.11    Results and findings of site audit in this reporting month are listed in Table 3.3.

 

4.4       Waste Management

4.4.1       The quantities of waste for disposal in the Reporting Period are summarized in Table 4.7. The Monthly Summary Waste Flow Table is shown in Appendix 4.5.

Table 4.7     Summary of Quantities of Waste Material

Waste Type

Quantity this month

Quantity

(the end of last month)

Cumulative Quantity-to-Date

Hard Rock and Large Broken Concrete (Inert)

(in ‘000m3)

0

0

0

Reused in this Contract (Inert)

(in ‘000m3)

0

0

0

Reused in other Projects (Inert)

(in ‘000m3)

0

0

0

Disposal as Public Fill (Inert)

(in ‘000m3)

0.11181

1.30758

13.21906

Metals (in ‘000kg)

0

0.0043

7.51480

Paper / Cardboard Packing

(in ‘000kg)

0.0397

0.0227

0.45918

Plastics

(in ‘000kg)

0.0069

0.0092

0.05476

Chemical Wastes

(in ‘000kg)

0

0

0

General Refuses

(in ‘000kg)

11.98

5.85

524.39


 

5              Complaints, Notification of Summons and Prosecution

5.1.1       No environmental complaint was recorded in the reporting month.

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

5.1.3       Cumulative statistic on complaints, summary of complaints and successful prosecutions are summarized in Table 5.1, Table 5.2 and Table 5.3 respectively.

 

Table 5.1     Cumulative Statistics on Complaints

Reporting Period

No. of Complaints

Septmeber 2023

0

Project commencement to the end of last reporting month

2

Total

2

 

 

Table 5.2     Summary of Complaints

Date of Notification from EPD

Date of Complaint

Description of Complaint

Validity of Complaint

Close-Out Date / Status

26 May 2022

22 May 2022

A complaint is regarding noise nuisance from marine site of San Shek Wan, Lantau Island.

Based on the investigation, the works activities of marine works did not result in any noise nuisance to Noise Sensitive Receivers (NSRs), noise nuisance from the Project is unlikely to be valid.

The interim report was submitted to EPD in June 2022. EPD replied no further comments on the final investigation report on 13 July 2022.

23 Dec 2022

21 Dec 2022

A complaint is regarding to the water quality for Pui O Beach, Lantau Island.

Based on the investigation, the works activities at POPS did not result in any water quality impacts to the Pui O Beach.

The interim report was submitted to EPD on 4 Jan 2023.

 

 

 

 

 

Table 5.3     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

 


 

6              Future Key Issues

6.1.1       In coming reporting 3 months, the scheduled construction activities are listed as follows:

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

·          HDD works at marine and SSWSTW

·          Site formation works

·          Drilling works

·          Excavation works

·          ELS works

·          Superstructure RC Works

·          Removal works of ELS

 

6.1.2       The scheduled construction activities and the recommended mitigation measures for the coming 3 months are listed in Table 6.1. The major construction activities for the next 3 months are summarized in Three Months Rolling Programme - October 2023 to December 2023 in Appendix 6.1.

Table 6.1     Construction Activities and Recommended Mitigation Measures in Coming Reporting 3 Months

Key Construction Works

Recommended Mitigation Measures

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

·         HDD works at marine and SSWSTW

·         Site formation works

·         Drilling works

·         Excavation works

·         ELS works

·         Superstructure RC Works

·         Removal works of ELS

 

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

·         Dust control during dust generating works;

·         Silt curtain should be maintained in good condition;

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

·         Adopt temporary drainage and sediment control facilities on Site;

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

·         Regular water spraying on excavation works for dust control; and

·         Proper waste handling, recycling and storage.


 

7              Conclusion

7.1          Noise Monitoring

7.1.1       No school examination was taken place at N17 – Bui O Public School in the reporting period.

7.1.2      No action or limit level exceedance was recorded in construction noise level in this reporting period.

 

7.2          Water Quality Monitoring

7.2.1      Marine-based construction works commenced on 19 April 2022, HDD casing works commenced on 30 May 2022.

7.2.2      Water quality monitoring on 1 Sep 2023 and 8 Sep 2023 were cancelled due to Typhoon Signal no. 8 and Black Rainstorm Signal respectively. 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.

7.2.3      In accordance with the action level and limit level in Baseline Monitoring Report Rev. 9.2 agreed by EPD on 2 September 2022, no action level and limit level exceedances were recorded in the reporting month.

 

7.3          Ecological Impact Monitoring

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

7.3.2       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.

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

7.3.4       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. To minimize obstruction to the public, the trees were subsequently sawn and removed. Incident report for this case would be provided by the Contractor.

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

7.3.6      Within this reporting period, holding nursery visit for transplanted trees on 21 September 2023.

7.3.7       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 7.1.

 

Table 7.1              Summary of Ecological Impact Monitoring

Inspection Date

Reminder and Recommendations

Close-out Date / Status

21 September 2023.

Transplanted trees in holding nursery at Kam Tin

The Contractor was reminded to remove other herbaceous plant species from Aquilaria sinensis (T392), Gmelina chinensis (T751) and Celtis sinensis(T113).

27 September  2023

 

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

7.4.1      No environmental non-compliance was recorded in the reporting month.

 

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

7.5.1      There was no particular action taken since no non-compliance was recorded in the reporting period.