CONTRACT NO: SD 6/2020
 
Construction of San Shek Wan Sewage Treatment Works

Associated Submarine Outfall and Pui O Sewerage Works

 

Under Environmental Permit no. EP-538/2017
 
Monthly Environmental Monitoring & Audit Report
 
may 2022
revision 3


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:



 

 

_______________________________

Melody Cheng

Environmental Team Leader

 

 

 

DATE:

 

 

14 June 2022

 

 


Table of contents

 

1      Introduction.. 6

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

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

2      Environmental Status. 8

2.1.......... Construction Programme. 8

2.2.......... Works undertaken during the month.. 8

2.3.......... Drawing showing the project area, environmental sensitive receivers and monitoring locations. 8

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. 9

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

3.4.......... Site Inspection and Audit Reports. 10

5.     Monitoring Results. 12

4.1.......... Noise Monitoring. 12

4.2.......... Water Quality Monitoring. 15

4.3.......... Ecology. 22

4.4.......... Waste Management 23

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

7.     Others. 26

7       Conclusion.. 28


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 (EM&A manual)

Table 4.7     Review of Exceedances in Turbidity and SS (proposed “and” approach)

Table 4.8       Summary of Quantities of Waste Material (as of April 2022)

Table 5.1       Summary of Complaints in the Reporting Month

Table 5.2       Cumulative Statistics on 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

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 – May 2022 to July 2022


 

EXECUTIVE SUMMARY

       i.        This is the Environmental Monitoring and Audit (EM&A) Monthly Report – May 2022 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 EM&A report presenting the environmental monitoring findings and information recorded during the period of 01 May 2022 to 31 May 2022. The cut-off date of reporting is at the end of each reporting month.

 

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

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

·          Tree pruning at POSPS

·          Maintenance works for trees in holding nursery and construction site

·          Excavation, sewer laying, construction of manhole at Pui O Lo Uk Tsuen

·          Excavation at South Lantau Road

·          HDD works

 

Exceedances of Action/Limit Levels

Noise Monitoring

     iii.        Noise monitoring was conducted at five (5) noise monitoring stations N12a, N12b, N13, N14 and N17 once per week in the reporting month.

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

 

 

Water Quality Monitoring

      v.        Marine-based construction works commenced on 19 April 2022. Water quality monitoring had been commenced on 12 April 2022 at seven (7) monitoring stations three days per week.

     vi.        Based on criteria in EM&A Manual, 118 action level and 0 limit level exceedances on DO, 11 action level and 55 limit level exceedances on turbidity, 8 action level and 52 limit level exceedances on SS were recorded in the reporting month.

    vii.        Overall exceedances on turbidity and SS (i.e. SR4, SR15 downstream to the construction site during mid-ebb, SR5, SR6, SR9, SR10 and SR12 exceedances downstream to the construction site during mid-flood,) in the reporting month were referred to the 20% / 30% of control station criteria only whereas there were no exceedance 95%-ile / 99%-ile, indicating that the exceedance is due to the localized water quality better than baseline range were captured at the control station whereas the impact station are still within the baseline ranges.  Co-related the monitoring dates with the marine works activities that only steel works, barge mobilization and general site housekeeping were conducted with no marine dredging works in the reporting month, it can be concluded that all these turbidity and SS exceedances were possibly due to natural runoff from streams to the sea as a result of frequent rainfall as recorded in the reporting month (Heavy showers, rainstorm and squally thunderstorms from 10 to 16 May 2022 and from 25 to 31 May 2022, Amber rainstorm warning signal recorded on 12 May 2022; Amber and Red rainstorm warning signals recorded on 13 May 2022).

   viii.        For Action level exceedances on DO were generally recorded at control station CE on most monitoring dates except 3, 5, 7 and 10 May 2022 and at control station CF on most monitoring dates except 3 and 7 May 2022 such that these recorded exceedance could be the background contribution to overall DO exceedances at the impact stations in general in the reporting month. Therefore, the exceedances could be the fluctuation around background ranges and hence considered as non-project related.

     ix.        No exceedance would be recorded if adopts the proposed change of Action and Limit Level criteria that proposed in the Baseline Monitoring Report.

 

Ecological Impact Monitoring

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

     xi.        Preservation of retain tree of Aquilaris sinensis on Project Site.

 

Complaint log

    xii.        One environmental complaint regarding the construction works was recorded in the reporting period.

 

Notifications of Any Summons and Successful Prosecutions

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

 

Reporting Changes

   xiv.        There are no particular reporting changes.

 


 

Future Key Issues

    xv.        In coming reporting 3 months, the scheduled construction activities and the recommended mitigation measures are listed as follows:

Key Construction Works

Recommended Mitigation Measures

·         Maintenance and establishment works for transplanted trees in holding nursery.

·         Preservation of existing trees on Project Site

 

 

·         Village sewers (excavation, sewer laying, construction of manhole) at Pui O Lo Uk Tsuen

 

 

 

 

 

·         Construction of POSPS

·         Horizontal directional drilling (HDD) works for SSWSTW land side

 

 

 

 

 

·         HDD works at sea side

·         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 in accordance with Construction Noise Mitigation Plan;

·         Dust control during dust generating works;

·         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 drilling and excavation works for dust control; and

·         Proper waste handling, recycling and storage.

 

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

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.     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        Environmental Status – 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

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        Others – An account of the future key issues as reviewed from the works programme and work method statements.

 

Section 7        Conclusion

2      Environmental Status

2.1          Construction Programme

2.1.1       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.

2.1.2       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.

2.1.3       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.

2.1.4       No construction programme with fine tuning of construction activities showing the inter-relationship with environmental protection/ mitigation measures for the month.

 

2.2          Works undertaken during the month

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

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

·         Tree pruning at POSPS

·         Maintenance works for trees in holding nursery and construction site

·         Excavation, sewer laying, construction of manhole at Pui O Lo Uk Tsuen

·         Excavation at South Lantau Road

·         HDD works

The locations of works are shown in Figure 2.2.

 

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

2.3.1       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. 12)

11 May 2022^

Condition 2.12

Submission of Compensatory Woodland Planting Plan (Rev. 5)

2 July 2021^

Condition 2.13

Silt Curtain Deployment Plan (Rev. 11)

29 April 2022^

Condition 2.14

Landscape Mitigation Plan

To be confirmed

Condition 2.15

Construction Noise Mitigation Plan (Rev. 14)

8 April 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

(dd-mm-yyyy to dd-mm-yyyy)

Status

Notification of Works Under APCO

466408

14 Apr 2021

N/A

Valid

Discharge Licence

POPS: WT00039820-2021

SSWSTW: WT00039636-2021

31 Dec 2021

 

30 Dec 2021

31-12-2021 to 31-12-2026

 

30-12-2021 to 31-12-2026

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

GW-RS0921-21

26 Nov 2021

29-11-2021 to 28-05-2022

Valid

GW-RS0428-22

26 May 2022

29-05-2022 to 28-11-2022

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 03, 10, 17, 23 May 2022 and 31 May 2022. IEC attended the SSEMC meeting held on 23 May 2022. Holding nursery visit for transplanted trees on 31 May 2022.

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

3 May 2022

Pui O Sewage Pumping Station

 

1.     To apply regular water spraying on exposed area

 

San Shek Wan Sewage Treatment Works

 

2.     Stockpiled material should be covered with impervious sheet to reduce dust nuisance

 

10 May 2022

10 May 2022

Site conditions are generally in order

-

17 May 2022

Pui O Sewage Pumping Station

1.     Deposit silt and grit should be removed regularly.

2.     Temporary drainage for surface runoff should be strengthened

3.     The effectiveness vehicle wheel-washing facilities should be enhanced

 

San Shek Wan Sewage Treatment Works

4.      Exposed stockpile should be covered

 

23 May 2022

Mid of June 2022

Mid of June 2022

 

 

 

23 May 2022

23 May 2022

Pui O Sewage Pumping Station

Reminder: Exposed area near Site entrance should be mitigated

1.     Cable on tree should be removed

2.     Tree Protection Zone should be enlarged

 

San Shek Wan Sewage Treatment Works

3. Enhance housekeeping on Site

 

Lo Uk Tsuen Sewer works

4. Stockpile should be covered

5. Dust and soil on ground to be cleared

 

 

 

25 May 2022

31 May 2022

 

 

25 May 2022

 

 

31 May 2022

25 May 2022

 

31 May 2022

Pui O Sewage Pumping Station

1.     Site temporary drainage is under construction

 

San Shek Wan Sewage Treatment Works

2. Site temporary drainage is under construction

 

Transplant trees in holding nursery

3. To carry out pest control for Transplant trees no. T113, T114.

 

Early June 2022

 

Early June 2022

 

 

 

31 May 2022

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 dB (A), the measurement would be considered invalid and repeat of noise measurement would be required after re-calibration or repair of the equipment.

 

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

0006346

Acoustic Calibrator

Honglim HLES-02

2016611465

 

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 five (5) noise monitoring stations N12a, N12b, N13, N14 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 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 (℃), 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℃ 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

17F100236

Turbid meter

Xin Rui WGZ-3B

2005060

 

 

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

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

 

Parameters monitored

4.2.9       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

4.2.10    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

4.2.11    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.

4.2.12    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.

4.2.13    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.

4.2.14    The sampling frequency of at least three days per week should be undertaken when the highest dust impact occurs. 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.

4.2.15    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

4.2.16    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

4.2.17    Water quality monitoring is evaluated against Action and Limit Levels. Note that derived Action and Limit Level was proposed in Baseline Monitoring Report for approval. Action and Limit Levels of marine water quality monitoring have been set with reference to the EM&A Manual criteria and derived criteria as shown in Table 4.5 below.

Table 4.5      Action and Limit Levels of Water Quality

Parameters

Action Level

Limit Level

Construction Phase Marine Water Monitoring - EM&A Manual criteria

DO in mg/L

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, or

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

23.5 NTU, or

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

SS in mg/L

(Depth-averaged  A) c

13.1 mg/L, or

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

30.4 mg/L, or

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

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.

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

Table 4.6      Summary of Marine Water Quality Exceedances (EM&A manual)

 

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

10/5/2022

16/5/2022

18/5/2022

20/5/2022

23/5/2022

25/5/2022

27/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

3/5/2022

10/5/2022

14/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

3/5/2022

10/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

-

-

-

18/5/2022

23/5/2022

 

15

13

 

Limit

-

-

-

-

3/5/2022

7/5/2022

10/5/2022

14/5/2022

16/5/2022

18/5/2022

31/5/2022

3/5/2022

5/5/2022

16/5/2022

18/5/2022

3/5/2022

5/5/2022

10/5/2022

14/5/2022

16/5/2022

31/5/2022

3/5/2022

10/5/2022

16/5/2022

13

7

SR5

Action

14/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

10/5/2022

14/5/2022

16/5/2022

20/5/2022

25/5/2022

27/5/2022

3/5/2022

10/5/2022

16/5/2022

18/5/2022

20/5/2022

23/5/2022

25/5/2022

27/5/2022

16/5/2022

23/5/2022

18/5/2022

23/5/2022

-

-

14

15

 

Limit

-

-

-

-

7/5/2022

10/5/2022

14/5/2022

31/5/2022

 

5/5/2022

7/5/2022

10/5/2022

16/5/2022

 

5/5/2022

10/5/2022

14/5/2022

23/5/2022

25/5/2022

31/5/2022

 

-

10

4

SR6

Action

16/5/2022

18/5/2022

20/5/2022

23/5/2022

25/5/2022

27/5/2022

14/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

-

-

-

-

14/5/2022

 

-

7

6

 

Limit

-

-

-

-

7/5/2022

10/5/2022

23/5/2022

25/5/2022

31/5/2022

5/5/2022

7/5/2022

16/5/2022

23/5/2022

 

5/5/2022

10/5/2022

23/5/2022

25/5/2022

3/5/2022

5/5/2022

10/5/2022

16/5/2022

23/5/2022

9

9

SR9

Action

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

31/5/2022

14/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

10/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

31/5/2022

27/5/2022

-

-

13

11

 

Limit

-

-

-

-

10/5/2022

18/5/2022

25/5/2022

5/5/2022

7/5/2022

10/5/2022

16/5/2022

23/5/2022

5/5/2022

10/5/2022

14/5/2022

25/5/2022

27/5/2022

31/5/2022

23/5/2022

9

6

SR10

Action

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

31/5/2022

14/5/2022

18/5/2022

23/5/2022

25/5/2022

27/5/2022

31/5/2022

-

-

-

-

-

18/5/2022

6

7

 

Limit

-

-

-

-

23/5/2022

25/5/2022

5/5/2022

23/5/2022

31/5/2022

5/5/2022

10/5/2022

14/5/2022

23/5/2022

25/5/2022

5/5/2022

10/5/2022

23/5/2022

 

7

6

SR12

Action

18/5/2022

20/5/2022

25/5/2022

27/5/2022

14/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

-

 

-

7/5/2022

25/5/2022

 

-

-

3/5/2022

6

6

 

Limit

-

-

-

-

23/5/2022

5/5/2022

7/5/2022

10/5/2022

23/5/2022

5/5/2022

10/5/2022

25/5/2022

10/5/2022

18/5/2022

23/5/2022

4

7

SR15

Action

14/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

3/5/2022

16/5/2022

18/5/2022

20/5/2022

25/5/2022

27/5/2022

-

-

7/5/2022

 

23/5/2022

31/5/2022

31/5/2022

5/5/2022

7/5/2022

8

10

 

Limit

-

-

-

-

3/5/2022

10/5/2022

16/5/2022

18/5/2022

31/5/2022

3/5/2022

7/5/2022

16/5/2022

18/5/2022

5/5/2022

10/5/2022

27/5/2022

3/5/2022

10/5/2022

16/5/2022

23/5/2022

8

8

Total

Action

41

37

20

20

6

5

2

6

137

 

Limit

0

0

0

0

27

28

33

19

107

4.2.19    In accordance with the EM&A Manual, 118 action level and 0 limit level exceedances on DO, 11 action level and 55 limit level exceedances on turbidity, 8 action level and 52 limit level exceedances on SS were recorded in the reporting month.

4.2.20    SR4 and SR15 located at upstream of construction site during mid-flood such that the Action and Limit Level exceedances on turbidity and SS along these stations in general were contributed by upstream sources before entering the submarine outfall construction location.  Similarly, SR5, SR6, SR9, SR10 and SR12 located at upstream of construction site during mid-ebb, such that the Action and Limit Level exceedances on turbidity and SS along these stations in general were contributed by upstream sources before entering the submarine outfall construction location.

4.2.21    Checked with contractor and RSS on the marine works activities in the reporting month, the following activities were recorded:

·         3/5/2022 - Cut off pipe pile of steel platform, Maintain silt curtain around marine platform

·         5/5/2022 - Weld safety fence on steel platform; Maintain silt curtain around marine platform

·         10/5/2022 - Working barge mobilized to site

·         25/5/2022 - Assemble and install steel casing for HDD works on the board

·         27/5/2022 - General site housekeeping (general cleansing on the board)

·         30/5/2022 - Install steel casing for HDD works to seabed

·         31/5/2022 - General site housekeeping (general cleansing on the board)

4.2.22    Overall exceedances on turbidity and SS (i.e. SR4, SR15 downstream to the construction site during mid-ebb, SR5, SR6, SR9, SR10 and SR12 exceedances downstream to the construction site during mid-flood,) in the reporting month were referred to the 20% / 30% of control station criteria only whereas there were no exceedance as referred to 95%-ile / 99%-ile criteria, indicating that the exceedance is due to the localized water quality better than baseline range were captured at the control station whereas the impact station are still within the baseline ranges. 

4.2.23    Co-related the monitoring dates with the marine works activities that only steel works, barge mobilization and general site housekeeping were conducted with no marine dredging works in the reporting month, it can be concluded that all these turbidity and SS exceedances were possibly due to natural runoff from streams to the sea as a result of frequent rainfall as recorded in the reporting month (Heavy showers, rainstorm and squally thunderstorms from 10 to 16 May 2022 and from 25 to 31 May 2022, Amber rainstorm warning signal recorded on 12 May 2022; Amber and Red rainstorm warning signals recorded on 13 May 2022).

4.2.24    For Action level exceedances on DO were generally recorded at control station CE on most monitoring dates except 3, 5, 7 and 10 May 2022 and at control station CF on most monitoring dates except 3 and 7 May 2022 such that these recorded exceedance could be the background contribution to overall DO exceedances at the impact stations in general in the reporting month. Therefore, the exceedances could be the fluctuation around background ranges and hence considered as non-project related.

4.2.25    Reviewing the “and“ approach, no exceedance is recorded if it is based on the ‘AND’ criteria proposed in Baseline Monitoring Report v7.3 Section 3.8.2 submitted in May 2022 (Table 4.7).  Majority of the exceedance were considered to be false alarm with review of the “and“ approach for counteracting the over-sensitivity of control station criteria as proposed in the baseline report.

 

Table 4.7      Review of Exceedances in Turbidity and SS (proposed “and” approach)

 

Parameter

Turbidity

SS

Exceedance count

Station

Level exceeded

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

 

Limit

0

0

0

0

0

 

 


 

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       The original location of Aquilaris sinensis is at SSWSTW (Figure 2.5). The tree is transplanted to temporary holding nursery (Figure 2.6) for establishment.

4.3.6       Retain tree of Aquilaris sinensis at SSWSTW Project Site.

 

MONITORING DATE, TIME, FREQUENCY AND DURATION

4.3.7       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.

4.3.8       Monitoring programme for post-transplantation will be conducted once per month (31 May 2022).

MONITORING RESULTS

4.3.9       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 4.6. The Monthly Summary Waste Flow Table is shown in Appendix 4.5.

 

Table 4.8 Summary of Quantities of Waste Material (as of April 2022)

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)

0.21077

0.62390

6.58375

Metals (in ‘000kg)

0.00000

0.00450

1.56170

Paper / Cardboard Packing

(in ‘000kg)

0.00000

0.04600

0.07048

Plastics

(in ‘000kg)

0.00000

0.00350

0.01046

Chemical Wastes

(in ‘000kg)

0

0

0

General Refuses

(in ‘000kg)

17.38#

9.74

293.49

*: Further breakdown into sub-group if considered applicable;

*: Please also provide daily dumping report for our records.

*: Delete as appropriate

#: 5000kg of timber recycled.

 

5.      Complaints, Notification of Summons and Prosecution

5.1.1       One environmental complaint, notification of summons and successful prosecution regarding construction works was recorded in the reporting period.

Table 5.1 Summary of Complaints in the Reporting Month

Date of Notification from EPD

Date of Complaint

Description of Complaint

Close-Out Date / Status

26 May 2022

22 May 2022

A complaint is regarding to a resident listened the construction noise within restricted hours (around 3 p.m. on 22/5/2022) at marine site from San Shek Wan, Lantau Island received.

The interim report to be submitted to EPD in Early June 2022.

The investigation, subsequent actions and the results will be recorded in the Monthly EM&A Report for June 2022

 

5.1.2       Cumulative statistic on complaints and successful prosecutions are summarized in Table 5.2 and Table 5.3 respectively.

Table 5.2 Cumulative Statistics on Complaints

Reporting Period

No. of Complaints

May 2022

1

Project commencement to the end of last reporting month

-

Total

0

 

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.      Others

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

·          Maintenance and establishment works for transplanted trees in holding nursery.

·          Preservation of existing trees on Project Site

·          Village sewers (excavation, sewer laying, construction of manhole) at Pui O Lo Uk Tsuen

·          Construction of POSPS

·          Horizontal directional drilling (HDD) works for SSWSTW land side

·          HDD works

 

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 - June 2022 to August 2022 in Appendix 6.1.

 

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

Key Construction Works

Recommended Mitigation Measures

·         Maintenance and establishment works for transplanted trees in holding nursery.

·         Preservation of existing trees on Project Site

 

 

·         Village sewers (excavation, sewer laying, construction of manhole) at Pui O Lo Uk Tsuen

 

 

 

 

 

·         Construction of POSPS

·         Horizontal directional drilling (HDD) works for SSWSTW land side

 

 

 

 

 

 

·         HDD works at sea side

·         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 in accordance with Construction Noise Mitigation Plan;

·         Dust control during dust generating works;

·         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 drilling and excavation works for dust control; and

·         Proper waste handling, recycling and storage.

 

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


 

7        Conclusion

7.1    Noise Monitoring.

7.1.1       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, water quality monitoring was commenced on 12 April 2022.  

7.2.2       Based on criteria in EM&A Manual, 118 action level and 0 limit level exceedances on DO, 11 action level and 55 limit level exceedances on turbidity, 8 action level and 52 limit level exceedances on SS were recorded in the reporting month. No exceedance would be recorded if adopts the proposed change of Action and Limit Level criteria that proposed in the Baseline Monitoring Report.

 

7.3    Ecological Impact Monitoring

7.3.1       Maintenance works for transplanted Aquilaris sinensis have commenced, preservation and protection of retain tree Aquilaris sinensis at SSWSTW.

 

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.


 

 

 

 

 

 

 

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


 

 

 

 

 

 

 

Appendix 4.1

 

Copies of Calibration Certificates


 

 

 

 

 

 

 

Appendix 4.2

 

Impact Monitoring Schedule


 

 

 

 

 

 

 

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

 

Three Months Rolling Programme – June 2022 to August 2022