Revision History
|
Rev. |
Description of Modification |
Date |
|
1. |
First Issue for Comments |
22/03/2024 |
|
2. |
Revisd according Comments |
27/03/2024 |
|
3. |
Revisd according Comments |
28/03/2024 |
|
4 |
Revisd according Comments |
02/04/2024 |
CONTENTS
Summary of Monitoring Exceedance, Complaints, Notification of Summons and Prosecutions31
Appendix A Master Programme
Appendix B Overview of Desalination Plant in Tseung Kwan O
Appendix C Summary of Implementation Status of Environmental Mitigation
Appendix D Water Quality Monitoring Graphical Presentation
Appendix E Summary of Exceedances
Appendix F Waste Flow Table
Appendix G Complaint Log
Appendix H Event/Action Plan for Water Quality Monitoring
Appendix I Event/Action Plan for Construction Noise Exceedance
Appendix J Event/Action Plan for Coral Monitoring Exceedance
Introduction
A1. The Project, Design, Build and Operate First Stage of Tseung Kwan O Desalination Plant (TKODP), is a Designated Project under the Environmental Impact Assessment Ordinance (Cap. 499) (EIAO) and is currently governed by a Further Environmental Permit (EP No. FEP - 01/503/2015/A) for the construction and operation of the Contract.
A2. In accordance with the Environmental Monitoring and Audit (EM&A) Manual for the Contract, EM&A works for marine water quality, noise, waste management and ecology should be carried out by Environmental Team (ET), Acuity Sustainability Consulting Limited (ASCL), during the construction phase of the Contract.
A3. This is the 16th Quarterly EM&A Report, prepared by ASCL, for the Contract summarizing the monitoring results and audit findings of the EM&A programme at and around Tseung Kwan O Area 137 (TKO 137) during the reporting period from 1 December 2023 to 29 February 2024.
A4. The EM&A programme for this contract has covered environmental monitoring on construction noise level at selected NSRs and Contractor’s environmental performance auditing in the aspects of construction dust, construction noise, water quality, waste management, Landscape and Visual and Ecology.
Summary of Main Works Undertaken & Key Mitigation Measures Implemented
A5. Key activities carried out in this reporting period for the Project included the followings:
|
Administration Building - Carrying out the floor tiles works at G/F - External wall painting works - Construction of block work for pipe duct - Installation of building services, cable laying, electrical switchboard, testing and commissioning |
|
Chemical building - Installation of leakage collection pit cover - Underground utility construction work - Landscape work at roof - Defect rectification |
|
Main Electrical & Central Chiller Plant Building - Installation of chillers, building services, electrical switchboard and cable laying - Installation of Roof Tile for Fuel Tank Room |
|
ActiDAFF - Underground utility construction work - Installation of access opening cover - Construction of staircase no 2 - Installation of mechanical equipment, piping system, installation of building services, electrical switchboards and cable laying, fiber-reinforced plastic cover Installation |
|
Product Water Storage Tank Building - Installation of Cat Ladders in Water Tank A - Sealing slab opening in water Tank A - Re-construction of Wall PW8 in Water Tank A -
Installation of metal
cladding, building
services, cable laying, mechanical equipment, steel pipe - Underground utility construction |
|
OSCG Building - Protective Coating for dangerous goods Rooms - Placing Soil Mix at Roof - Installation of Metal Cladding (at East Side) and Roller Shutters and Window - Underground utility construction work - Installation of building services, mechanical equipment and cable laying, testing and commissioning |
|
Reverse Osmosis Building - Installation of building services, electrical switchboard, cable laying, Installation of mechanical equipment, steel pipe, Glass Reinforced Plastic pipe, raised floor, testing and commissioning - Installation of metal cladding, handrailing, roller shutters, glass canopy and glass house - Underground utility construction work - Construction of Reinforced Concrete External Wall for Male Toilet |
|
Post Treatment Building - Installation of building services, Installation of mechanical equipment and piping system, Pressure Test - Underground utility construction work - Installation of Cat Ladders in Water Tanks - Installation of Metal Cladding - Placing Soil Mix at Roof |
|
Inspection corridor - Installation of building services, Lift installation - Construction of roof tiling works and staircases no. 2 - Installation of Movement Joints and glass window |
|
CO2 Tanks - Installation of pipes and electrical wiring, testing and commissioning Combined Shaft and Pump room - Finishing, Grating; window; louvre installation Other - Watermain works at CLP 132 kV Substation - Staircases construction; Steel Bridge assembly and installation at elevated walkway - Road Construction, Footpath Construction, Landscape Construction, Irrigation System Construction, Water Pressure Test for Fire Services and Plumbing System in Zone A, B, C - Structure Construction, steel fence erection of Wave Deflector Wall at seawall area - Slope work |
A6. The major environmental impacts brought by the above construction works include:
- Construction dust and noise generation from excavation works, construction works, slope works and rock cutting works; and
- Waste generation from the construction activities
A7. The key environmental mitigation measures implemented for the Project in this reporting period associated with the above construction works include:
- Dust suppression by regular wetting and water spraying for construction works;
- Reduction of noise from equipment and machinery on-site and regularly inspection to machinery and plants/vehicles on-site to ensure proper functioning;
- Sorting and storage of general refuse and construction waste;
- Deployment of silt curtain at the inshore water outflow; and
- Deployment protective fencing for trees.
Summary of Exceedance & Investigation & Follow-up
A8. No noise monitoring was conducted during the reporting period since there are no project- related construction activities undertaken within a radius of 300m from the monitoring locations. No exceedance of the Action Level was recorded during the reporting period.
A9. Referring to EM&A Manual, the general water quality monitoring should be carried out when there are marine-related construction activities undertaken. General water quality monitoring at the ten monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36 and WSR37) was ceased from 1 September 2023 due to the completion of marine-related construction works.
A10. The pre-operation (testing and commissioning) phase of desalination plant started in reporting period. The EM&A works for pre-operation phase water quality were conducted during the reporting period in accordance with the EM&A Manual. Seventy-eight (78) of the
pre-operation phase water quality monitoring results of SS obtained had exceeded the Action Level. Fifty-nine (59) of the pre-operation phase water quality monitoring results of SS obtained during the reporting period had exceeded the Limit Level. After investigation, all exceedances were concluded unrelated to the Project.
A11. Dechlorinated effluent monitoring at two sampling locations (Sampling point T1GKC01AA502/manhole 18) during disinfection was carried out by AJCJV on 2 and 3 December 2023 for Total Residual Chlorine monitoring (TRC). Seven (7) of dechlorinated effluent sample were taken in Sampling point T1GKC01AA502/manhole 18. No TRC exceedance of action or limit levels was obtained during the discharge of dechlorinated effluent. The dechlorinated effluent monitoring is completed.
A12. In this reporting period, 216 times of landfill gas monitoring were recorded at Wan Po Road (Ch0+390 - Ch0+780) and (Ch0+400 - Ch1+200). No action and limit level exceedance for methane, oxygen and carbon dioxide was recorded.
A13. Pre-operation phase monthly coral monitoring was conducted during the reporting period on 28 December 2023, 30 January 2024 and 23 February 2024. No sediment, bleaching or increased mortality in the general condition of all other tagged coral colonies were observed during the monthly operation phase monitoring period. No deterioration of the coral community was observed in the ecological monitoring results when compared with the baseline ecological monitoring results. There is no AL/LL exceedance during the monitoring period.
A14. Pre-operation phase fishery monitoring for dry season was carried out on 17 and 24 February 2024. The result is of the monitoring would be present when it is available.
A15. Weekly site inspections of the construction works were also carried out by ET to audit the mitigation measures implementation status. Thirteen (13) times of weekly Joint site inspections were carried out by ET and IEC.
A16. A summary of the EM&A activities in this reporting period is listed in Table I and summary of the environmental exceedance of the reporting period is tabulated in Table II.
Table I Summary Table for EM&A
Activities in the Reporting Period
|
EM&A Activities |
Dec 2023 |
Jan 2024 |
Feb 2024 |
|
Noise Monitoring |
N/A |
N/A |
N/A |
|
Pre-operation Phase Water Quality Monitoring |
12, 14, 16, 19, 21, 23, 26, 28 and 20 December 2023 |
2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25, 27 and 30 January 2024 |
1, 3, 5, 7, 9, 12, 15, 17, 20, 22, 24, 27 and 29 February 2024 |
|
TRC Monitoring for Main Disinfection |
2 and 3 December 2023 |
N/A |
N/A |
|
Pre-operation Phase Coral Monitoring |
28 December 2023 |
30 January 2024 |
23 February 2024 |
|
Pre-operation Phase Fishery Monitoring |
N/A |
N/A |
17 and 24 February 2024 |
|
Landfill Gas monitoring |
1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23, 27, 28 and 29 December 2023 |
2, 8, 9, 10, 11 and 12 January 2024 |
1, 2, 3, 5, 6, 7, 8, 9, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24, 26, 27, 28 and 29 February 2024 |
|
Environmental Site Inspection |
5, 12, 19, 27 December 2023 |
2, 9, 16, 25 and 29 January 2024 |
7, 16, 20 and 28 February 2024 |
Table II Summary Table
for Exceedance in the Reporting Period
|
Environmental Monitoring |
Parameter |
No. of non- Project
related exceedance |
Total No. of non-Project related exceedance |
No. of Project
related exceedance |
Total No. of
Project related exceedance |
||
|
AL |
LL |
AL |
LL |
||||
|
Noise |
Leq (30min) |
N/A |
N/A |
N/A |
N/A |
N/A |
N/A |
|
Water |
DO |
0 |
0 |
0 |
0 |
0 |
0 |
|
Turbidity |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
SS |
78 |
59 |
137 |
0 |
0 |
0 |
|
|
pH |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Salinity |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
TRC |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
Water (Main Disinfection) |
TRC |
0 |
0 |
0 |
0 |
0 |
0 |
|
Landfill Gas |
O2 |
0 |
0 |
0 |
0 |
0 |
0 |
|
CH4 |
0 |
0 |
0 |
0 |
0 |
0 |
|
|
CO2 |
0 |
0 |
0 |
0 |
0 |
0 |
|
Complaint Handling and
Prosecution
A17. One (1) environmental complaint was received during the reporting period. No notifications of summons or prosecution was received during the reporting period.
Reporting Change
A18. There was no change to be reported that may affect the on-going EM&A programme.
Basic Project
Information1.1.
Background
The Acciona Agua, S.A. Trading, Jardine Engineering Corporation Limited and China State Construction Engineering (Hong Kong) Limited and as AJC Joint Venture (AJCJV) is contracted to carry out the Design, Build and Operate First Stage of Tseung Kwan O Desalination Plant (DPTKO) under Contract No. 13/WSD/17 (the Contract).
Acuity Sustainability Consulting Limited (ASCL) is commissioned by AJCJV to undertake the Environmental Team (ET) services as required and/or implied, both explicitly and implicitly, in the Environmental Permit (EP), Environmental Impact Assessment Report (EIA Report) (Register No. AEIAR-192/2015) and Environmental Monitoring and Audit Manual (EM&A Manual) for the Contract; and to carry out the Environmental Monitoring and Audit (EM&A) programme in fulfillment of the EIA Report’s EM&A requirements and Contract No. 13/WSD/17 Specification requirements.
Pursuant to the Environmental Impact Assessment Ordinance (EIAO), the Director of Environmental Protection granted the Environmental Permit (No. EP-01/503/2015) and Variation of Environmental Permit (No. EP-01/503/2015/A) to Water Supplies Department (WSD); and granted the Further Environmental Permit (No. FEP-01/503/2015/A) to AJCJV for the Contract.
1.2.
The Reporting Scope
This is the 16th Quarterly EM&A Report for the Project which summarizes the key findings of the EM&A programme during the reporting period from 1 December 2023 to 29 February 2024.
1.3.
Project Organization
The Project Organization structure for Construction Phase is presented in Figure 1.1.
Figure 1.1 Project Organization Chart
Contact details of the key personnel are presented in Table 1.1 below:
Table 1.1 Contact Details
of Key Personnel
|
Party |
Position |
Name |
Telephone no. |
Remark |
|
Project Proponent |
SE/CM2 |
Milton Law |
2634-3573 |
/ |
|
Supervising Officer (Binnies Hong Kong Limited) |
Project Manager |
Christina Ko |
2608-7302 |
/ |
|
Chief Resident Engineer |
Roger Wu |
6343-1002 |
/ |
|
|
The Jardine Engineering Corporation, Limited, China State Construction Engineering (Hong Kong) Limited and Acciona Agua, S.A. Trading |
Project Manager |
Stephen Yeung |
2807-4665 |
/ |
|
Environmental Monitoring Manager |
Brian Kam |
9456-9541 |
/ |
|
|
Environmental Monitoring Manager |
Joy Chan |
6468-1782 |
/ |
|
|
Acuity Sustainability Consulting Limited |
Environmental Team Leader |
Jacky Leung |
2698-6833 |
/ |
|
ANewR Consulting Limited |
Independent Environmental Checker (IEC) |
Alex Chan |
2618-2831 |
(Until the end of January 2024) |
|
Lam Environmental Services Limited |
Independent Environmental Checker (IEC) |
Serena Shek |
6149-6683 |
(Started from February 2024) |
1.4.
Summary of Construction Works
Details of the major construction activities undertaken in this reporting period are shown as below. The construction programme is presented in Appendix A.
|
Administration Building - Carrying out the floor tiles works at G/F - External wall painting works - Construction of block work for pipe duct - Installation of building services, cable laying, electrical switchboard, testing and commissioning |
|
Chemical building - Installation of leakage collection pit cover - Underground utility construction work - Landscape work at roof - Defect rectification |
|
Main Electrical & Central Chiller Plant Building - Installation of chillers, building services, electrical switchboard and cable laying - Installation of Roof Tile for Fuel Tank Room |
|
ActiDAFF - Underground utility construction work - Installation of access opening cover - Construction of staircase no 2 - Installation of mechanical equipment, piping system, installation of building services, electrical switchboards and cable laying, fiber-reinforced plastic cover Installation |
|
Product Water Storage Tank Building - Installation of Cat Ladders in Water Tank A - Sealing slab opening in water Tank A - Re-construction of Wall PW8 in Water Tank A -
Installation of metal
cladding, building
services, cable laying, mechanical equipment, steel pipe - Underground utility construction |
|
OSCG Building - Protective Coating for dangerous goods Rooms - Placing Soil Mix at Roof - Installation of Metal Cladding (at East Side) and Roller Shutters and Window - Underground utility construction work - Installation of building services, mechanical equipment and cable laying, testing and commissioning |
|
Reverse Osmosis Building - Installation of building services, electrical switchboard, cable laying, Installation of mechanical equipment, steel pipe, Glass Reinforced Plastic pipe, raised floor, testing and commissioning - Installation of metal cladding, handrailing, roller shutters, glass canopy and glass house - Underground utility construction work - Construction of Reinforced Concrete External Wall for Male Toilet |
|
Post Treatment Building - Installation of building services, Installation of mechanical equipment and piping system, Pressure Test - Underground utility construction work - Installation of Cat Ladders in Water Tanks - Installation of Metal Cladding - Placing Soil Mix at Roof |
|
Inspection corridor - Installation of building services, Lift installation - Construction of roof tiling works and staircases no. 2 - Installation of Movement Joints and glass window |
|
CO2 Tanks - Installation of pipes and electrical wiring, testing and commissioning Combined Shaft and Pump room - Finishing, Grating; window; louvre installation Other - Watermain works at CLP 132 kV Substation - Staircases construction; Steel Bridge assembly and installation at elevated walkway - Road Construction, Footpath Construction, Landscape Construction, Irrigation System Construction, Water Pressure Test for Fire Services and Plumbing System in Zone A, B, C - Structure Construction, steel fence erection of Wave Deflector Wall at seawall area - Slope work |
1.5.
Summary of Environmental Status
A summary of the valid permits, licences, and /or notifications on environmental protection for this Project is presented in Table 1.2.
Table 1.2 Summary of the Status
of Valid Environmental Licence, Notification, Permit
and Documentations
|
Permit/ Licences |
Valid Period |
Status |
Remark |
|
|
From |
To |
|||
|
Environmental Permit |
||||
|
EP - 503/2015/A |
Throughout the Contract |
Valid |
- |
|
|
FEP - 01/503/2015/A |
Throughout the Contract |
Valid |
- |
|
|
Notification of Construction Works under the Air Pollution Control (Construction Dust) Regulation (Form NA) |
||||
|
451539 |
Throughout the Contract |
Valid |
- |
|
|
Billing Account for Disposal of Construction Waste |
||||
|
7036276 |
Throughout the Contract |
Valid |
- |
|
|
Chemical Waste
Producer Registration |
||||
|
5213-839-A2987-01 |
Throughout the Contract |
Valid |
- |
|
|
Wastewater Discharge Licence (Land and Marine
works) |
||||
|
WT00035775-2020 |
23/08/2021 |
31/07/2025 |
Valid |
- |
|
WT00044188-2023 |
16/06/2023 |
30/06/2025 |
Valid |
- |
|
Construction Noise
Permit |
||||
|
GW-RE0640-23 |
22/06/2023 |
21/12/2023 |
Valid |
- |
|
GW-RE1514-23 |
22/12/2023 |
21/06/2024 |
Valid |
- |
The status for all environmental aspects is presented in Table 1.3
Table 1.3 Summary of Status for Key Environmental Aspects under the EM&A Manual
|
Parameters |
Status |
|
Water Quality |
|
|
Baseline Monitoring under EM&A Manual |
The baseline water quality monitoring was conducted between 12 May 2020 and 6 June 2020 |
|
Construction Phase Impact Monitoring |
Ceased from 1 September 2023 |
|
Pre-operation Phase Impact Monitoring |
On-going |
|
TRC Monitoring for Main Disinfection |
Completed |
|
Noise |
|
|
Baseline Monitoring |
The baseline noise monitoring result has been reported in Baseline Monitoring Report and submitted to EPD under EP Condition 3.4 |
|
Impact Monitoring |
Completed |
|
Waste Management |
|
|
Mitigation Measures in Waste Management Plan |
On-going |
|
Landfill Gas |
|
|
Regular Monitoring when Construction Works are within the 250m Consultation Zone |
In this reporting period, 216 times of landfill gas monitoring were recorded at Wan Po Road (Ch0+390 - Ch0+780) and (Ch0+400 - Ch1+200). No exceedance of action or limit level for methane, oxygen and carbon dioxide was observed |
|
Ecology (Coral) |
|
|
Pre-operation phase Regular Coral Monitoring (Monthly) |
On-going |
|
Ecology (Fishery) |
|
|
Pre-operation phase Regular Fishery Monitoring (Seasonally) |
On-going |
|
Ecology (Landscape) |
|
|
Pre-operation phase Landscape and Visual Site Inspection |
On-going |
|
Environmental Audit |
|
|
Site Inspection covering Measures of Air Quality, Noise Impact, Water Quality, Waste, Ecological Quality, Fisheries, Landscape and Visual |
On-going |
Other than the EM&A work by ET, environmental briefings, trainings and regular environmental management meetings were conducted, in order to enhance environmental awareness and closely monitor the environmental performance of the contractors.
The EM&A programme has been implemented in accordance with the recommendations presented in the approved EIA Report and the EM&A Manual. A summary of implementation status of the environmental mitigation measures for the construction phase and pre-operation phase of the Project during the reporting period is provided in Appendix C.
Noise2.1.
Monitoring Requirements
To ensure no adverse noise impact, construction noise monitoring is recommended to be carried out within 300m radius from the nearby noise sensitive receivers (NSRs), during construction phase. The NSRs selected as monitoring station are (i) NSR4 - Creative Secondary School, (ii) NSR24 - PLK Laws Foundation College, and (iii) NSR31 - School of Continuing and Professional Studies - CUHK respectively.
No impact construction noise monitoring was conducted in the reporting period due to the overly distant monitoring station from the works location, where they were farther than 1 km from the closet monitoring station NSR4 to the works location.
2.2.
Monitoring Parameters, Frequency and Duration
Construction noise level would be measured in terms of the A-weighted equivalent continuous sound pressure level (LAeq). Leq 30min was used as the monitoring parameter for the time period between 0700 and 1900 on normal weekdays. Table 2.1 summarizes the monitoring parameters, frequency and duration of the impact noise monitoring.
Table 2.1 Noise Monitoring Parameters, Time, Frequency
and Duration
|
Time |
Duration |
Interval |
Parameters |
|
Daytime: 0700-1900 |
Day time: 0700-1900 (during normal weekdays) |
Continuously in Leq 5min/Leq 30min (average of 6 consecutive Leq 5min) |
Leq 30min L10 30min & L90 30min |
2.3.
Monitoring Locations
The monitoring locations should normally be made at a point 1m from the exterior of the NSRs building façade and be at a position 1.2m above the ground. A correction of +3dB(A) should be made to the free-field measurements.
According to the environmental findings detailed in the EIA report and Baseline Monitoring Report, the designated locations for the construction noise monitoring are listed in Table 2.2 below.
Table 2.2 Noise Sensitive
Receivers
|
NSR ID |
Noise Sensitive Receivers |
Monitoring Location |
Position |
|
NSR 4 |
Creative Secondary School |
Roof Floor |
1 m from facade |
|
NSR 24 |
PLK Laws Foundation College |
Pedestrian Road on Ground
Floor |
Free-field |
|
NSR 31 |
School of Continuing and Professional
Studies - CUHK |
Roof Floor |
1 m from facade |
The monitoring locations should normally be made at a point 1m from the exterior of the NSRs building façade and be at a position 1.2m above the ground. A correction of +3dB(A) should be made to the free-field measurements. Three noise monitoring locations for impact monitoring at the nearby sensitive receivers are shown in Figure 2.1-2.3.
|
|
|
Figure 2.1 NSR4 Creative Secondary School |
|
|
|
Figure 2.2 NSR24 PLK Laws Foundation College |
|
|
|
Figure 2.3 NSR31 School
of Continuing and Professional Studies - CUHK |
2.4.
Action and Limit Levels
The Action/Limit Levels are in line with the criteria of Practice Note for Professional Persons (ProPECC PN 2/93) “Noise from Construction Activities - Non-statutory Controls” and Technical Memorandum on Environmental Impact Assessment Process issued by HKSAR Environmental Protection Department [“EPD”] under the Environmental Impact Assessment Ordinance, Cap 499, S.16 are presented in Table 2.3.
Table 2.3 Action and Limit Levels
for Construction Noise
Monitoring per EM&A
Manual
|
Time Period |
Action Level |
Limit Level (dB(A)) |
|
0700-1900 on normal weekdays |
When one documented complaint is received from any one of the noise sensitive receivers |
- 70 dB(A) for school and - 65 dB(A) during examination period |
Notes: Limits specified in the GW-TM
and IND-TM for construction and operation noise,
respectively.
If exceedances were found during noise monitoring, the actions in accordance with the Event and Action Plan shall be carried out according to Appendix E.
2.5.
Monitoring Results and Observations
Referring to EM&A manual Section 4.1.2, the impact noise monitoring should be carried out when there are project-related construction activities undertaken within a radius of 300m from the monitoring stations. As no Contract-related construction activities were undertaken in the reporting period within a radius of 300m from the monitoring stations of the Project site as shown in Figure 2.4, no impact noise monitoring was conducted in the reporting period.
Figure 2.4 Site Layout
Plan with Noise Sensitive Receivers and Desalination Plant
In accordance with the recommendations of the EIA, water quality monitoring is required during dredging for the submarine pipelines and, during operation phase. In addition, baseline water quality monitoring was conducted prior to the commencement of marine construction activities. Additional water quality monitoring was conducted during pre-operation.
The following Section provides details of the water quality monitoring to be undertaken by the Environmental Team (ET) to verify the distance of sediment and brine plume dispersion and to identify whether the potential exists for any indirect impacts to occur to ecological sensitive receivers. The water quality monitoring programme was carried out to allow any deteriorating water quality to be readily detected and timely action taken to rectify the situation.
Water quality monitoring for the Project can be divided into the following stages:
- Dredging activities during construction phase;
- Discharge of effluent from main disinfection during construction phase;
- Commissioning activities during pre-operation (testing and commissioning) phase
- Operation phase - first year upon operation; and,
- Continuous monitoring of effluent quality.
3.1.
Water Quality Parameters
The parameters that have been selected for measurement in situ and in the laboratory are those that were either determined in the EIA
to be those with the most potential to be affected by the construction works or are a standard
check on water quality conditions. Parameters measured in the impact monitoring are listed in Table 3.1
Table 3.1 Parameters
measured in the impact marine water quality monitoring
|
Parameters |
Unit |
Abbreviation |
|
In-situ measurements |
||
|
Dissolved oxygen |
mg/L |
DO |
|
Temperature |
oC |
- |
|
pH |
- |
- |
|
Turbidity |
NTU |
- |
|
Salinity |
0/00 |
- |
|
Total Residual Chlorine |
mg/L |
TRC |
|
Total Residual Chlorine (Disinfection) |
mg/L |
TRC |
|
Laboratory measurements |
||
|
Suspended Solids |
mg/L |
SS |
|
Iron |
mg/L |
|
|
Anti-scalant |
mg/L |
- |
NOTE 1: Monitoring of Total
Residual Chlorine (Disinfection) will be conducted when cleaning and sterilization of the new freshwater
main is carried out.
In addition to the water quality parameters, other relevant data were measured and recorded in Water Quality Monitoring Logs, including the location of the sampling stations, water depth, time, weather conditions, sea conditions, tidal stage, current direction and velocity, special phenomena and work activities undertaken around the monitoring and works area that may influence the monitoring results.
3.2.
Monitoring Locations
Pre-operation (testing and commissioning) Phase
The impact
water quality monitoring locations are detailed
in Table 3.2 and
shown in Figure 3.1
below.
Table 3.2 Location
of Impact Water Quality
Monitoring Station
|
Station |
Easting |
Northing |
Description |
|
CE |
843550 |
815243 |
Upstream control station at ebb tide |
|
CF |
846843 |
810193 |
Upstream control station at flood tide |
|
WSR1 |
846864 |
812014 |
Ecological sensitive receiver at Tung Lung Chau |
|
WSR2 |
847645 |
812993 |
Fisheries sensitive receiver at Tung Lung Chau |
|
WSR3 |
848023 |
813262 |
Ecological sensitive receiver at Tung Lung Chau |
|
WSR4 |
847886 |
814154 |
Ecological sensitive receiver at Tai Miu Wan |
|
WSR16 |
845039 |
815287 |
Ecological sensitive receiver at Fat Tong Chau |
|
WSR33 |
847159 |
814488 |
Ecological sensitive receiver at Tai Miu Wan |
|
WSR36 |
846878 |
814081 |
Ecological sensitive receiver at Kwun Tsai |
|
WSR37 |
846655 |
813810 |
Ecological sensitive receiver at Tit Cham Chau |
|
NF1 |
846542 |
813614 |
Edge of mixing zone, ~ 200m west of outfall diffuser |
|
NF2 |
846942 |
813614 |
Edge of mixing zone, ~ 200m east of outfall diffuser |
|
NF3 |
846742 |
813414 |
Edge of mixing zone, ~ 200m south of outfall diffuser |
Figure 3.1 Impact Water Quality Monitoring
Locations under EM&A Manual
Main Disinfection
According to the approved Flushing and Disinfection Procedure and Supplementary of the Disinfection Procedure for Desalination Plant at Tseung Kwan O, the sampling point of the dechlorinated effluent was located at Contact tank/Product Water Tank (PWT) and T1GKC01AA502/manhole 18.
The approved sampling location was shown in Table 3.3, Figure 3.2 and Figure 3.3 below.
Table 3.3 Sampling location of dechlorinated effluent
|
System/Loop |
Discharge location |
Sampling Location |
Parameter |
|
Contact tank/ Product Water Tank (PWT) |
Culvert |
Contact tank/PWT |
TRC |
|
Connection to dist. network |
Manhole 18 in connection point |
Sampling point T1GKC01AA502/manhole 18 |
Figure 3.2 Impact water quality
monitoring point for dechlorinated effluent (Contact
tank/PWT)
Figure 3.3 Impact water quality
monitoring point for dechlorinated effluent (Sampling
point T1GKC01AA502/manhole 18)
3.3.
Monitoring Equipment, Methodology and QA/QC Procedures
The monitoring methodology, equipment used, and QA/QC procedures could be referred to Section 3.1.2 -3.1.4, 3.1.6-3.1.7 and 3.2 of the Monthly EM&A Report.
3.4.
Action and Limit
levels
The Action and Limit Levels have been set based on the derivation criteria specified in the EM&A Manual and based on the baseline water quality monitoring data and the derivation criteria, the Action/Limit Levels have been derived and are presented in Table 3.4.
Table 3.4 Derived Action and Limit Levels for Water Quality
|
Parameters |
Action |
Limit |
|
Pre-Operation (Testing and Commissioning) Phase
Impact Monitoring |
||
|
DO in
mg/L |
Surface and
Middle 7.30 mg L-1 Bottom 7.31 mg L-1 Tung Lung Chau Fish
Culture Zone 5.1 mgL-1 or level
at control station (Whichever the lower) |
Surface and Middle 4 mg L-1 Bottom 2 mg L-1 Tung Lung Chau Fish
Culture Zone 5.0 mgL-1 or level
at control station (Whichever the lower) |
|
SS in mg/L
(Depth- averaged) |
5.00 mg L-1 or 20% exceedance of value at any impact
station compared with corresponding data
from control station |
6.00 mg L-1 or 30% exceedance of value
at any impact station compared with corresponding data from control station |
|
Turbidity in NTU (Depth- averaged) |
2.41 NTU or 20% exceedance of value
at any impact station compared with corresponding data
from control station |
2.84 NTU or 30% exceedance of value at any impact station compared with corresponding data from control station |
|
Salinity in PSU (Depth- averaged) |
34.28 PSU or 9% exceedance of value at any impact station
compared with corresponding data from control station |
34.60 PSU or 10% exceedance of value at any impact
station compared with corresponding data
from control station |
|
Iron in mg/L (Depth- averaged) |
0.3 mg/L |
0.3 mg/L |
|
Total residual chlorine in mg/L |
0.01 mg/L |
0.01 mg/L |
|
Total residual chlorine in mg/L (Disinfection) |
0.1 mg/L |
0.1 mg/L |
Notes:
i.
"Depth-averaged" is calculated by taking the arithmetic means
of reading of all three
depths.
ii.
For DO, non-compliance of the water quality limits
occurs when monitoring result is lower than the limits.
iii.
For Turbidity, SS, iron and Salinity, non-compliance of the water quality limits
occurs when monitoring result is higher than
the limits.
3.5.
Monitoring Results and Observations
Construction Phase
Referring to EM&A Manual, the general water quality monitoring should be carried out when there are marine-related construction activities undertaken. General water quality monitoring at the ten monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36 and WSR37) was ceased from 1 September 2023 due to the completion of marine-related construction works.
Pre-operation (testing and commissioning) Phase
Considering the first pre-operation phase of Tseung Kwan O Desalination Plant was started in the reporting period, additional marine water quality monitoring was conducted at the thirteen monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36, WSR37, NF1,
NF2 and NF3) from 12 December 2023. The Action and Limit Level would be referred to the approved EM&A Manual Table 5.4 First-year Operation Phase Marine Water Monitoring.
The additional marine water quality monitoring was conducted at the thirteen monitoring stations on 12, 14, 16, 19, 21, 23, 26, 28 and 20 December 2023, 2, 4, 6, 9, 11, 13, 16, 18, 20, 23, 25, 27 and 30 January 2024 and 1, 3, 5, 7, 9, 12, 15, 17, 20, 22, 24, 27 and 29 February 2024 during the reporting quarter. The result of the reporting quarterly is presented in Table 3.5.
Seventy-eight (78) of the pre-operation phase water quality monitoring results of SS obtained had exceeded the Action Level. Fifty-nine (59) of the pre-operation phase water quality monitoring results of SS obtained during the reporting period had exceeded the Limit Level.
Investigation on the reason of exceedance has been carried out, where the exceedances of SS were concluded to be unrelated to the Contract as detailed in the Incident Reports on Action Level or Limit Level. Summary of the exceedance is presented in Appendix E.
Table 3.5 Summary of Impact Water Quality Monitoring Results
|
Location |
Parameter |
|||||||||||||||||||||||||||
|
Salinity (ppt) |
Dissolved Oxygen
(mg/L) |
pH |
Turbidity (NTU) |
Suspended Solids
(mg/L) |
Temp. (oC) |
TRC (mg/L) |
Iron (mg/L) |
|||||||||||||||||||||
|
Surface & Middle |
Bottom |
|||||||||||||||||||||||||||
|
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
Dec |
Jan |
Feb |
||
|
CE |
Avg. |
33.1 |
32.9 |
33.5 |
9.1 |
9.1 |
8.5 |
9.0 |
9.1 |
8.5 |
7.2 |
7.3 |
7.6 |
3.0 |
2.4 |
2.4 |
3.9 |
4.0 |
3.3 |
21.8 |
23.3 |
21.9 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
Min. |
32.1 |
32.2 |
32.6 |
7.4 |
8.5 |
7.7 |
7.4 |
8.4 |
7.7 |
6.6 |
7.1 |
7.2 |
2.2 |
1.7 |
2.0 |
3.0 |
2.5 |
2.5 |
21.0 |
21.7 |
20.1 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
|
Max.. |
34.5 |
33.8 |
34.2 |
10.1 |
9.5 |
9.3 |
10.1 |
9.5 |
9.4 |
7.6 |
7.4 |
8.0 |
3.8 |
3.2 |
2.7 |
6.0 |
7.0 |
8.0 |
22.4 |
24.4 |
23.1 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
|
CF |
Avg. |
33.0 |
32.7 |
33.2 |
9.2 |
9.1 |
8.5 |
9.2 |
9.1 |
8.6 |
7.1 |
7.3 |
7.6 |
3.2 |
2.4 |
2.6 |
3.8 |
3.9 |
3.2 |
21.9 |
23.3 |
21.9 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
Min. |
32.3 |
31.8 |
32.7 |
7.9 |
8.7 |
7.8 |
7.8 |
8.7 |
7.8 |
6.6 |
7.1 |
7.1 |
2.5 |
1.8 |
2.1 |
2.5 |
2.5 |
2.5 |
20.9 |
21.9 |
20.1 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
|
Max.. |
34.2 |
33.9 |
34.0 |
10.0 |
9.8 |
9.2 |
10.1 |
9.8 |
9.1 |
7.4 |
7.4 |
8.0 |
4.0 |
3.0 |
3.1 |
7.0 |
7.0 |
9.0 |
22.6 |
24.4 |
23.4 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
|
WSR1 |
Avg. |
33.2 |
32.8 |
33.2 |
9.0 |
8.9 |
8.4 |
9.1 |
8.9 |
8.4 |
7.2 |
7.3 |
7.6 |
2.2 |
2.0 |
1.9 |
4.0 |
4.1 |
3.4 |
21.9 |
23.3 |
21.9 |
<0.01 |
<0.01 |
<0.01 |
<0.1 |
<0.1 |
<0.1 |
|
Min. |
32.3 |
31.4 |
32.4 |
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