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   april 2022 revision 2.4

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. 11

4.    Monitoring Results.. 13

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

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

4.3.......... Ecology. 23

4.4.......... Waste Management 24

5.    Complaints, Notification of Summons and Prosecution.. 25

6.    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       Cumulative Statistics on Complaints

Table 5.2       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 – April 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 April 2022 to 30 April 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:

·          Maintenance works for tree in holding nursery and Site

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

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

·          Excavation of Trial Pit at Chi Ma Wan Road and South Lantau Road

·          Pre-drilling works at Pui O beach road

·          Preparation of HDD works

·          Installation of silt curtain and construction of temporary marine platform

 

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. Results to be provided.

     vi.        Marine-based construction works commenced on 19 April 2022, water quality monitoring was commenced on 12 April 2022.  66 action level exceedances on DO, 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month.

    vii.        Out of 66 action level exceedances on DO, 61 of these exceedances were due to background contribution as recorded at the control stations on 14, 16, 18, 20, 22 and 29 April 2022 whereas action level exceedance on DO recorded at SR9 and SR10 on 27 April 2022 were reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

   viii.        Out of the 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month, 4 action level exceedances on SS were concluded after removing those false alarm exceedance using the “and“ approach proposed in the baseline report.  Action level exceedance on SS recorded on 27 April 2022 was reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

 

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

 

Complaint log

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

 

Notifications of Any Summons and Successful Prosecutions

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

 

Reporting Changes

   xiii.        Commencement date of marine works was 19 May 2022 and silt curtain installation works was commenced on the same day.

 

 

Future Key Issues

   xiv.        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 and Chi Ma Wan Beach ·         Trunk Sewers and Rising Mains outside village and to POSPS       ·         Construction of POSPS ·         Horizontal directional drilling (HDD) works for SSWSTW land side ·         Retaining wall construction and slope modification works at SSWSTW         ·         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 exposed area; and ·         Proper waste handling, recycling and storage.   ·         Silt curtains should be installed to surround the marine dredging area in accordance with Silt Curtain Deployment Plan.

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:

·          Maintenance works for tree in holding nursery and Site

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

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

·          Excavation of Trial Pit at Chi Ma Wan Road and South Lantau Road

·          Pre-drilling works at Pui O beach road

·          Preparation of HDD works

·          Installation of silt curtain and construction of temporary marine platform

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.               

 

3.1.2       Ecological mitigation measures – Preservation and protection of trees of Aquilaris sinensis. Advices are the following:

a)     Protection and preservation of retain tree Aquilaris sinensis (tree no. T370) on Project Site;

b)    Proper soiling and mulching practices for transplanted tree Aquilaris sinensis (tree no. T392) in holding nursery.

c)     Timely conduct rectification works to enhance recovery of tree in transit nursery.

 

3.1.3       Landscape & Visual mitigation measures – Transplantation of 6 trees no. T113, T114, T742, T751, T758 and T392 have completed on 1^st March 2022. Advices are the following:

a)     Monitoring and maintaining transplanted trees in holding nursery should follow General Specification of Civil Engineering Works – Section 3 and “Guidelines on Tree Transplanting” specified in EM&A Manual.

b)    Timely conduct rectification works to enhance recovery of tree in transit nursery.

 

3.1.4       Tree Protection and Preservation - Retain trees in the Project Site should be protected and preserved in accordance with CEDD G.S. Section 3 and DEVB TC(W) No. 7/2015. In particular, maintaining Tree Protection Zone with proper tree label.

 

3.1.5       Water quality mitigation measures – Silt curtain should be installed around the dredging area and pilot hole exit area vertically from sea surface to seabed. The silt curtain extent, offset distance from the works area should follow Silt Curtain Deployment Plan.

 

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

 

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

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

 

 

3.4  Site Inspection and Audit Reports

6.        

7.        

7.0.        

3.4.1       Within this reporting month, weekly environmental site inspections were conducted on 06, 13, 19 and 26 April 2022. IEC attended the SSEMC meeting held on 19 April 2022. Holding nursery visit for transplanted trees on 26 April 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

3.1. 

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 (L_eq). L_{eq (30min)} should be used as the monitoring parameter. Supplementary information for data auditing, statistical results such as L₁₀ and L₉₀ shall also be obtained for reference.

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

 

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

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 L_eq(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

5.0.        

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: 0-360^o, 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, water quality monitoring commenced on 12 April 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

5     

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

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	14/04/22 18/04/22 20/04/22	18/04/22 20/04/22	18/04/22 20/04/22 22/04/22 29/04/22	18/04/22 22/04/22	-	-	-	-	7	4
	Limit	-	-	-	-	12/04/22 14/04/22 18/04/22 20/04/22 22/04/22 25/04/22 27/04/22 29/04/22	12/04/22 18/04/22 20/04/22 22/04/22 25/04/22 27/04/22 29/04/22	16/04/22 20/04/22 25/04/22 27/04/22 29/04/22	18/04/22 20/04/22 22/04/22 25/04/22 27/04/22	13	12
SR5	Action	14/04/22 18/04/22 20/04/22	18/04/22 20/04/22 22/04/22	14/04/22 16/04/22 20/04/22 22/04/22 29/04/22	20/04/22 22/04/22 29/04/22	18/04/22 22/04/22	-	18/04/22	-	11	6
	Limit	-	-	-	-	12/04/22 14/04/22 20/04/22 22/04/22 25/04/22 27/04/22 29/04/22	18/04/22 20/04/22 22/04/22 25/04/22 27/04/22 29/04/22	14/04/22 16/04/22 20/04/22 22/04/22 25/04/22 27/04/22	18/04/22 20/04/22 22/04/22 27/04/22	13	10
SR6	Action	16/04/22 20/04/22 22/04/22	18/04/22 20/04/22 22/04/22 29/04/22	-	-	-	-	-	-	3	4
	Limit	-	-	-	-	12/04/22 14/04/22 18/04/22 20/04/22 22/04/22 25/04/22 29/04/22	12/04/22 18/04/22 20/04/22 22/04/22 25/04/22 29/04/22	14/04/22 16/04/22 25/04/22 27/04/22	18/04/22 20/04/22 22/04/22	11	9
SR9	Action	12/04/22 14/04/22 18/04/22 27/04/22 29/04/22	29/04/22	12/04/22 16/04/22 18/04/22 20/04/22 22/04/22 27/04/22	18/04/22 20/04/22 22/04/22 27/04/22 29/04/22	-	-	-	-	11	6
	Limit	-	-	-	-	12/04/22 14/04/22 18/04/22 20/04/22 25/04/22 27/04/22	12/04/22 18/04/22 20/04/22 25/04/22 27/04/22 29/04/22	16/04/22	18/04/22 20/04/22	7	8
SR10	Action	16/04/22 20/04/22	20/04/22 22/04/22 27/04/22	-	-	27/04/22	-	20/04/22	-	4	3
	Limit			-	-	12/04/22 16/04/22 18/04/22 25/04/22 29/04/22	18/04/22 20/04/22 27/04/22 29/04/22	16/04/22 27/04/22	18/04/22 20/04/22 25/04/22 27/04/22	7	8
SR12	Action	16/04/22 20/04/22 22/04/22	20/04/22	-	-	-	20/04/22	-	-	3	2
	Limit	-	-	-	-	12/04/22 16/04/22 18/04/22 25/04/22 27/04/22	12/04/22 18/04/22 25/04/22 27/04/22	16/04/22 27/04/22	12/04/22 18/04/22 20/04/22 25/04/22 27/04/22	7	9
SR15	Action	12/04/22 16/04/22 18/04/22 20/04/22 22/04/22	12/04/22 14/04/22 20/04/22	-	-	-	-	-	-	5	3
	Limit	-	-	-	-	12/04/22 18/04/22 20/04/22 25/04/22 29/04/22	12/04/22 18/04/22 20/04/22 25/04/22 29/04/22	25/04/22 29/04/22	12/04/22 18/04/22 20/04/22 25/04/22	7	9
Total	Action	24	17	15	10	3	1	2	0	72
	Limit	0	0	0	0	43	38	22	27	130

4.2.19    In accordance with the EM&A Manual, 66 action level exceedances on DO, 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month.

4.2.20    With respect to marine-based construction works commenced on 19 April 2022, Event and Action Plan stated in EM&A Manual were implemented for exceedance recorded starting from 20 April 2022 whereas those monitoring results before 19 April 2020 were taken as reference.

4.2.21    Action level exceedances on DO were also recorded at control station CE on 14, 16, 18, 20, 22 and 29 April 2022 and control station CF on 14, 18, 20 and 22 April 2022 which such that these recorded exceedance could be the background contribution to DO exceedances at the impact stations on 14, 16, 18, 20, 22 and 29 April 2022.

4.2.22    For action level exceedance on DO recorded at SR9 and SR10 on 27 April 2022, no exceedance on DO were recorded at the nearby upstream stations SR5 and SR6 from the location of marine-based construction works, these exceedance was non-project related.

4.2.23    For turbidity and SS exceedances, no muddy water plume observed immediately outside the silt curtain on 19, 20, 21, 22, 25, 26, 28 and 29 April 2022 as per the site condition recorded by ET.  As such, 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.  Reviewing the “and“ approach, the number of exceedances recorded without false alarm are summarized in Table 4.7.

 

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	-	-	27/04/22	22/04/22	1	1
	Limit	-	-	-	-	0	0
SR5	Action	-	-	-	22/04/22	0	1
	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	-	-	-	12/04/22	0	1
	Limit	-	-	-	-	0	0
SR15	Action	-	-	-	-	0	0
	Limit	-	-	-	-	0	0
Total	Action	0	0	1	3	4
	Limit	0	0	0	0	0

 

4.2.24    Avoiding false alarm notification was considered in the Event and Action Plan implementation.  For the action level exceedance on SS recorded on 27 Apr 2022, no exceedance on SS were recorded at the nearby stations SR5 and SR6 from the marine-based construction works, these exceedance was non-project related.

4.2.25    After considering the above-mentioned investigation results, it is concluded that out of 66 action level exceedances on DO, 61 of these exceedances were due to background contribution as recorded at the control stations on 14, 16, 18, 20, 22 and 29 April 2022 whereas action level exceedance on DO recorded at SR9 and SR10 on 27 April 2022 were reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

4.2.26    Out of the 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month, 4 action level exceedances on SS were concluded after removing those false alarm exceedance using the “and“ approach proposed in the baseline report.  Action level exceedance on SS recorded on 27 April 2022 was reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

 

 

4.3       Ecology

MONITORING METHODOLOGY

4        

4.1        

4.2        

4.3        

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 (26 April 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)	0.62390	2.51320	6.37295
Metals (in ‘000kg)	0.00450	1.55	1.56170
Paper / Cardboard Packing (in ‘000kg)	0.04600	0	0.07048
Plastics (in ‘000kg)	0.00350	0	0.01046
Chemical Wastes (in ‘000kg)	0	0	0
General Refuses (in ‘000kg)	9.74	34.82	276.11

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

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

*: Delete as appropriate

 

5.      Complaints, Notification of Summons and Prosecution

8.        

8.0.        

5.1.1       No environmental complaint, notification of summons and successful prosecution regarding construction works was recorded in the reporting period.

5.1.2       Cumulative statistic on complaints and successful prosecutions are summarized in Table 5.1 and Table 5.2 respectively.

Table 5.1 Cumulative Statistics on Complaints

Reporting Period	No. of Complaints
April 2022	0
Project commencement to the end of last reporting month	-
Total	0

 

Table 5.2 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

9.        

9.0.        

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

·          Maintenance works for tree in holding nursery and Site

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

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

·          Excavation of Trial Pit at Chi Ma Wan Road and South Lantau Road

·          Pre-drilling works at Pui O beach road

·          Preparation of HDD works

·          Installation of silt curtain and construction of temporary marine platform

 

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 - May 2021 to Jul 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 and Chi Ma Wan Beach ·         Trunk Sewers and Rising Mains outside village and to POSPS       ·         Construction of POSPS ·         Horizontal directional drilling (HDD) works for SSWSTW land side ·         Retaining wall construction and slope modification works at SSWSTW       ·         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 exposed area; and ·         Proper waste handling, recycling and storage.   ·         Silt curtains should be installed to surround the marine dredging area in accordance with Silt Curtain Deployment Plan.

 

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.  66 action level exceedances on DO, 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month.

7.2.2       Out of 66 action level exceedances on DO, 61 of these exceedances were due to background contribution as recorded at the control stations on 14, 16, 18, 20, 22 and 29 April 2022 whereas action level exceedance on DO recorded at SR9 and SR10 on 27 April 2022 were reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

7.2.3       Out of the 4 action level and 81 limit level exceedances on turbidity, 2 action level and 49 limit level exceedances on SS were recorded in the reporting month, 4 action level exceedances on SS were concluded after removing those false alarm exceedance using the “and“ approach proposed in the baseline report.  Action level exceedance on SS recorded on 27 April 2022 was reviewed with no exceedance recorded at nearby upstream stations SR5 and SR6 from the location of marine-based construction works and concluded as non-project related.

 

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 – May 2022 to July 2022