Revision History
Rev. |
Description of Modification |
Date |
1. |
First Issue for Comments |
09/10/2024 |
2 |
Second Issue for Comments |
11/10/2024 |
CONTENTS
8. Summary of Exceedance, Complaints, Notification of Summons and Prosecutions.............. 41
Appendix A |
Overview of Desalination Plant in Tseung Kwan O |
Appendix B |
Summary of Implementation Status of Environmental Mitigation |
Appendix C |
Impact Monitoring Schedule |
Appendix D |
Event/Action Plan |
Appendix E |
Water Quality Monitoring Equipment and Landfill Gas Equipment Calibration Certificate |
Appendix F |
Water Quality Monitoring Data and Landfill Gas Monitoring Data |
Appendix G |
Waste Flow Table |
Appendix H |
Ecology (Coral & Fishery) Survey Report |
Appendix I |
Site Inspection Proforma |
Appendix J |
Complaint Log |
Appendix K |
Exceedance Report |
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/B) for the operation phase 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, waste management and ecology should be carried out by Environmental Team (ET), Aurecon Hong Kong Limited (Aurecon), during the Tseung Kwan O Desalination Plant.
A3. The TKODP commenced the operation stage on 1 July 2024. This is the 3rd Operation Phase Monthly EM&A Report, prepared by Aurecon, 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 first-year operation of Tseung Kwan O Desalination Plant in September 2024.
A4. The EM&A programme for this contract has covered environmental monitoring on water quality and Contractor’s environmental performance auditing in the aspects of dust, landfill gas, water quality, waste management, Landscape and Visual and Ecology.
Summary of exceedance & investigation &
follow-up
WATER QUALITY
MONITORING
A5. The EM&A works for operation phase marine water quality were conducted during the reporting period in accordance with the EM&A Manual. Twelve (12) of SS obtained had exceeded the Action Level. Twenty (20) of SS obtained during the reporting period had exceeded the Limit Level.
A6. The EM&A works for continuous monitoring of effluent quality were conducted during the reporting period in accordance with the EM&A Manual. No exceedance of the sampling was obtained during the reporting period had exceeded the Limit Level.
Ecology Impact
Monitoring
A7. Monthly operation phase coral monitoring works was conducted on 18 September 2024. There is no AL/LL exceedance during the monitoring period.
A8. Operation phase fishery monitoring for wet season 2024 was carried out on 24 and 31 August 2024. The detail of the monitoring will be presented when the result is available.
Landfill Gas
Monitoring
A9. In this reporting period, monthly landfill gas monitoring was conducted on 25, 26 and 27 September 2024. No exceedances of action level and limit level was observed.
Weekly Site Inspections
A10. In this reporting period, site inspections were carried out by ET on 3, 10, 17 and 24 September 2024. Joint site inspections of the operation work by ET were and IEC were carried out on 24 September 2024 to audit the mitigation measures implementation status.
Complaint Handling
and Prosecution
A11. No environmental complaint, notification of summons and prosecution was received in the reporting period.
Reporting Change
A12. There was no change to be reported that may affect the on-going EM&A programme.
A13. According to the contractor’s information, the works of TKODP were substantially completed on 30 June 2024 and the plant commenced the operation phase on 1 July 2024. The outstanding construction works were being carried out during this reporting period. Details of the construction phase monitoring will be presented in the Construction Phase Monthly EM&A Report.
Background
1.1. The Acciona Agua, S.A. Trading, Jardine Engineering Corporation, Limited and China State Construction Engineering (Hong Kong) Limited as AJC Joint Venture (AJCJV) is contracted to carry out the Design, Build and Operate First Stage of Tseung Kwan O Desalination Plant (TKODP) under Contract No. 13/WSD/17 (the Contract).
1.2. Aurecon Hong Kong Limited (Aurecon) 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.
1.3. Pursuant to the Environmental Impact Assessment Ordinance (EIAO), the Director of Environmental Protection granted the Environmental Permit (No. EP-01/503/2015/B) to Water Supplies Department (WSD); and granted the Further Environmental Permit (No. FEP-01/503/2015/B) to AJCJV for the Contract.
The Reporting Scope
1.4. This is the 3rd Operation Phase Monthly EM&A Report for the Contract which summarizes the key findings of the EM&A programme of the Tseung Kwan O Desalination Plant Operation phase during the reporting period from 1 September 2024 to 30 September 2024.
Contract Organization
1.5. The Contract Organization structure for Operation Phase is presented in Figure 1.1.
Figure 1.1 Contract Organization Chart
1.6. 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. |
Contract Proponent (Water Supplies Department) |
SE/CM2 |
Milton Law |
2634-3573 |
Supervising Officer (Binnies Hong Kong Limited) |
Project Manager |
Augustine Li |
2608-7671 |
Senior Resident Engineer |
David Wong |
5229-8638 |
|
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 |
|
Operation Manager |
Arnes Parra, Victor |
6468-6710 |
|
Environmental Monitoring Manager |
Tommy Law |
6468-1782 |
|
Aurecon Hong Kong Limited |
Environmental Team Leader |
Toby Wan |
9719-5422 |
Lam Environmental Services Limited |
Independent Environmental Checker (IEC) |
Serena Shek |
6149-6683 |
Summary of Operation Works
1.7. Details of the major operation activities undertaken in this reporting period are shown below.
1.8. As informed by the Contractor, key activities carried out in this reporting period for the Contract included the followings:
-
Potable Water Production
1.9. The key environmental mitigation measures implemented for the Contract in this reporting period associated with the above operation works include:
- Regularly monitoring of the effluent
- Sorting and storage of general refuse and operation waste
1.10. Summary of the valid permits, licences, and/or notifications on environmental protection for this Contract 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/B |
Throughout the Contract |
Valid |
-Issued on 3 April 2024 |
|
FEP - 01/503/2015/B |
Throughout the Contract |
Valid |
-Issued on 3 April 2024 |
|
Billing Account
for Disposal |
||||
7036276 |
Throughout the Contract |
Valid |
- |
|
Sludge (Special Waste) Disposal (Admission Ticket) |
||||
17913 |
01/07/2024 |
24/12/2024 |
Valid |
|
17372 |
12/06/2024 |
31/12/2024 |
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 |
30/06/2028 |
Valid |
- For Plant T&C and operation. - Variation sampling point S.P.1 is approved by the EPD on 25 June 2024 (EPD ref.: EP640/W3/D1358/ 462874). The variation of application of discharge license was submitted on 9 Sep 2024 and pending for EPD approval |
1.11. 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 to 6 Jun 2020. |
Operation phase Marine Impact Monitoring |
On-going |
Continuous Monitoring of Effluent Quality |
On-going |
Waste Management |
|
Mitigation Measures in Waste Management Plan |
On-going |
Landfill Gas |
|
Monthly Monitoring for buildings, manholes and utility pits within the Project Site and along the fresh water mains |
On-going |
Ecology (Coral) |
|
Operation phase Regular Coral Monitoring (Monthly) |
On-going |
Ecology (Fishery) |
|
Operation phase Regular Fishery Monitoring (Seasonally) |
On-going |
Landscape |
|
Operation phase Landscape and Visual Site Inspection |
On-going |
Environmental Audit |
|
Site Inspection covering Measures of Air Quality, Water Quality, Waste, Ecological Quality, Fisheries, Landscape and Visual |
On-going |
1.12. 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.
1.13. 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 operation phase of the Contract during the reporting period is provided in Appendix B.
2.1. In accordance with the recommendations of the EIA, water quality monitoring is required during operation phase. 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.
2.2. 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.
2.3. Water quality monitoring for the Contract can be divided into the following stages:
(a) Operation phase Marine Water Quality Monitoring - first year upon commissioning
(b)Continuous Monitoring of Effluent Quality
Water Quality Parameters
2.4. Parameters to be measured in the marine water quality monitoring and the Continuous Monitoring of Effluent Quality are listed in Table 2.1 and Table 2.2 respectively.
a) Operation phase Marine Water Quality Monitoring
2.5. The parameters for the marine water quality monitoring 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 operation works or are a standard check on water quality conditions.
Table 2.1 Parameters measured in the 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 |
Laboratory measurements |
||
Suspended Solids |
mg/L |
SS |
Iron-Soluble |
mg/L |
Fe |
Anti-scalant as Reactive Phosphorus* |
mg/L |
PO4 as P- |
*Remark: Anti-scalant water quality testing
will only be conducted whenever
anti-scalant
dosage is adopted.
b) Continuous Monitoring of Effluent Quality
2.6. The monitoring requirement for the continuous effluent quality monitoring shall be conducted in accordance with the effluent parameters and standards stipulated by the Water Pollution Control Ordinance Discharge License (No.: WT00044188-2023) conditions.
Table 2.2 Parameters measured in the Continuous Monitoring of Effluent Quality
Parameters |
Unit |
Abbreviation |
In-situ measurements |
||
Temperature |
oC |
- |
pH |
pH |
- |
Salinity |
0/00 |
- |
Total Residual Chlorine |
mg/L |
TRC |
Laboratory measurements |
||
Suspended Solids |
mg/L |
SS |
Iron-Soluble |
mg/L |
Fe |
Total Inorganic Nitrogen |
mg/L |
- |
Total Phosphorus |
mg/L |
- |
Sodium Metabisulphite |
mg/L |
SMBS |
Anti-scalant as Reactive Phosphorus * |
mg/L |
PO4 as P- |
*Remark: Anti-scalant water quality testing
will only be conducted whenever
anti-scalant
dosage is adopted.
2.7. In addition to the marine water quality parameters, other relevant data were also being 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.
Monitoring Equipment
a) Operation phase Marine Water Quality Monitoring
2.8. For water quality monitoring, the following equipment were used:
Dissolved Oxygen and Temperature Measuring Equipment - The instrument was a portable, weatherproof dissolved oxygen measuring instrument complete with cable, sensor, comprehensive operation manuals, and was operable from a DC power source. It was capable of measuring: dissolved oxygen levels in the range of 0 - 20 mg/L and 0 - 200% saturation; and a temperature of 0 - 45 degrees Celsius. It has a membrane electrode with automatic temperature compensation complete with a cable of not less than 35 m in length. Sufficient stocks of spare electrodes and cables were available for replacement where necessary (e.g. YSI model 59 DO meter, YSI 5739 probe, YSI 5795A submersible stirrer with reel and cable or an approved similar instrument).
Turbidity Measurement Equipment - The instrument was a portable, weatherproof turbidity-measuring unit complete with cable, sensor and comprehensive operation manuals. The equipment was operated from a DC power source, it has a photoelectric sensor capable of measuring turbidity between 0 - 1000 NTU and complete with a cable with at least 35 m in length (for example Hach 2100P or an approved similar instrument).
Salinity Measurement Instrument - A portable salinometer capable of measuring salinity in the range of 0 - 40 ppt was provided for measuring salinity of the water at each monitoring location.
Water Depth Gauge - A portable, battery-operated echo sounder (for example Seafarer 700 or a similar approved instrument) was used for the determination of water depth at each designated monitoring station. This unit will preferably be affixed to the bottom of the work boat if the same vessel is to be used throughout the monitoring programme. The echo sounder was suitably calibrated.
Positioning Device - A Global Positioning System (GPS) was used during monitoring to allow accurate recording of the position of the monitoring vessel before taking measurements. The Differential GPS, or equivalent instrument, was suitably calibrated at appropriate checkpoint (e.g. Quarry Bay Survey Nail) to verify that the monitoring station is at the correct position before the water quality monitoring commence.
Water Sampling Equipment - A water sampler, consisting of a PVC or glass cylinder of not less than two litres, which can be effectively sealed with cups at both ends, was used. The water sampler has a positive latching system to keep it open and prevent premature closure until released by a messenger when the sampler is at the selected water depth.
Total Residual Chlorine -Total residual chlorine (TRC) shall be measured in-situ using approved test kit.
b) Continuous Monitoring of Effluent Quality
2.9. The equipment to be used for the effluent quality monitoring was summarizes in Table 2.3.
Table 2.3 Parameters measured in the Continuous Monitoring of Effluent Quality
Equipment |
Model |
Refrigerated Sampler |
Teledyne ISCO 5800 |
Online sampler for real-time monitoring (Xylem WTW IQ SensorNet system and sensors) |
DIQ/S 284-PR: Universal Transmitter to operate up to 4 digital IQ sensors, with PROFIBUS-connection |
Equipment |
Model |
|
TetraCon® 700 IQ SW: Digital 4 electrode conductivity cell, in seawater design, suited for heavily polluted water, for use with the IQ SENSOR NET. With integrated temperature sensor |
VisoTurb® 700 IQ SW: Digital turbidity sensor for industrial and seawater applications (ultrasonic cleaning) for use with the IQ SENSOR NET system |
|
SensoLyt® 700 IQ SW: Robust digital pH/ORP sensor for SensoLyt® SEA/ DWA/ECA/PtA pH/ORP electrodes, in sea water design, for use with the IQ SENSOR NET. With built-in pre-amplifier and temperature sensor (NTC), with SensCheck function |
|
FDO®700 IQ SW: Digital calibration free optical D.O. sensor (universal use). Optimized for measuring and controlling the O2 input in seawater applications, for use with IQ SENSOR NET. Factory calibrated system composed of sensor FDO® 700 IQ SW, membrane cap SCFDO® 700 and protective cap MSK FDO® |
|
Chlorine 3017M: Online analyzer for photometric measurement of free and total chlorine, according to colorimetric DPD Method (ISO &US EPA); outputs (selectable): 4 to 20 mA or RS 485 |
Based on Section 5.1.3 of the EM&A Manual, the online sampler for real-time monitoring will be tested before use by HOKLAS-accredited laboratory and will be re-calibrated at monthly intervals throughout the stages of effluent quality monitoring.
Sampling / Testing Protocols
2.10. All in situ monitoring instruments were checked, calibrated, and certified by a laboratory accredited under HOKLAS or any other international accreditation scheme before use, and subsequently re-calibrated at monthly intervals throughout the stages of the water quality monitoring. Responses of sensors and electrodes were checked with certified standard solutions before each use.
2.11. On-site calibration of field equipment was following the “Guide to On-Site Test Methods for the Analysis of Waters”, BS 1427: 2009. Sufficient stocks of spare parts were maintained for replacements when necessary. Backup monitoring equipment was made available so that monitoring can proceed uninterrupted even when equipment is under maintenance, calibration etc.
Laboratory Measurement and Analysis
a) Operation phase Marine Water Quality Monitoring
2.12. Sufficient volume of each water sample was collected for carrying out the laboratory analyses. Using chain of custody forms, collected water samples were transferred to a HOKLAS accredited laboratory (Acumen Laboratory and Testing Limit - HOKLAS 241) for immediate processing. The determination work was start within the next working day after collection of the water samples. Analytical methodology and sample preservation of other parameters were based on the latest edition of Standard Methods for the Examination of Waste and Wastewater published by APHA, AWWA and WPCF and methods by USEPA, or suitable method in accordance with requirements of HOKLAS or another internationally accredited scheme. The QA/QC details were in accordance with the requirements of HOKLAS or another internationally accredited scheme.
2.13. Parameters for laboratory measurements, standard methods and detection limits are presented in Table 2.4.
Table 2.4 Laboratory measurements, standard methods, and corresponding detection limits of marine water quality monitoring
Parameters |
Standard Methods |
Detection Limit |
Reporting Limit |
Precision |
Dissolved oxygen |
Instrumental, CTD |
0.1 |
- |
+-25% |
Temperature |
Instrumental, CTD |
0.1 |
- |
+-25% |
pH |
Instrumental, CTD |
0.1 |
- |
+-25% |
Turbidity |
Instrumental, CTD |
0.1 |
- |
+-25% |
Salinity |
Instrumental, CTD |
0.1 |
- |
+-25% |
Suspended Solids |
APHA 23rd Ed 2540D |
1.0 |
2.5 |
+-17% |
Iron |
APHA 3111 B |
0.2 |
- |
+-25% |
Total residual chlorine |
APHA 4500CL: G |
0.01mg/L |
- |
+-25% |
Anti-scalant* |
Content acrylic polymers determination method |
5 mg/L |
- |
- |
*Remark: A proposal for update anti-scalant monitoring under the operation phase EM&A programme is proposed via email on 27 May 2024. EPD has agreed
to update the anti-scalant monitoring detection
limit, action and limit level from 0.2 mg/L to 5.0 mg/L (EPD ref. ()In EP 2/N8/E/120
Pt.14).
b) Continuous Monitoring of Effluent Quality
2.14. Analyses of the sample shall be carried out using American Public Health Association Standard Method for the Examination of Water and Wastewater or other internationally accepted standard methods proposed by the Licensee and approved by the Authority which could achieve the monitoring requirement.
Table 2.5 Measurements Methods for Continuous Monitoring of Effluent Quality
Parameters |
Standard Methods |
Flow Rate (m3 / day) |
In-house method |
Temperature(°C) |
Instrumental |
Salinity (0/00) |
Instrumental |
pH (pH units) |
Instrumental |
Suspended Solids (mg / L) |
APHA 2540E |
Iron (mg / L) |
APHA 3111 B |
Total Inorganic Nitrogen (mg / L) |
In-house method |
Total Phosphorous (mg / L) |
In-house method |
Total Residual Chlorine |
APHA 4500CL: G |
Sodium Metabisulphite |
-- |
Anti-scalant ‘ACUMER’ 4035* |
*Remark: Anti-scalant water quality testing
will only be conducted whenever
anti-scalant
dosage is adopted.
Monitoring Location
a) Operation phase Marine Water Quality Monitoring
2.15. The operation phase water quality monitoring locations are in accordance with the EM&A Manual and detailed in Table 2.6 below. A schedule for water quality monitoring was prepared by the ET and submitted to IEC and EPD prior to the commencement of the monitoring.
Table 2.6 Location of Water Quality Monitoring Stations
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 |
2.16. WSR1 to WSR37 were identified in accordance with Annex 14 of the EIAO-TM as well as Clause 3.4.4.2 of the Environmental Impact Assessment Study Brief for Desalination Plant at Tseung Kwan O (No. ESB-266/2013). WSR1 to WSR3 are sited near the Tung Lung Chau Fish Culture Zone; WSR16 and WSR36 are sited near the coral assemblages along the coastlines of Fat Tong Chau and Kwun Tsai respectively; WSR 4 and WSR33 are sited near the Coastal Protection Area and coral assemblages in waters of Tai Miu Wan; WSR37 is sited near the fisheries resource including spawning and nursery grounds at the coastal water of Tit Cham Chau. NF1 to NF3 are the Edge of Mixing zone.
Figure 2.1 Water Quality Monitoring Locations under EM&A Manual
b) Continuous Monitoring of Effluent Quality
2.17. In accordance with the discharge license, the Continuous Monitoring shall be sampling at Brine Outfall Shaft.
Figure 2.2 Continuous Monitoring locations
Sampling Frequency
a) Impact Marine Water Quality Monitoring
2.18. Water quality monitoring was carried out three days per week during the operation phase. Monitoring at each station was undertaken once per day. The interval between two sets of monitoring was not less than 36 hours. The monitoring frequency would be increased in the case of exceedances of Action/Limit Levels if considered necessary by ET. Monitoring frequency would be maintained as far as practicable.
b) Continuous Monitoring of Effluent Quality
2.19. The effluent should be collected in a full 24-hour period. Twenty four-hour flow- weighted composite effluent sample for subsequent chemical analysis and testing should be prepared by the following procedures:
-
Collect effluent sub-sample at bi-hourly interval
over a 24 hour period
-
Obtain flow record of the Project
for the 24-hour
sampling period
-
Calculate the volume of each sub-sample for preparation of flow-weighted
composite sample
-
Transfer the appropriate volume of sub-samples to a clean container and mix
thoroughly
Sampling Depths & Replication
a) Operation phase Marine Water Quality Monitoring
2.20. During water quality monitoring, each station was sampled, and measurements/ water samples were taken at three depths, 1 m below the sea surface, mid-depth, and 1 m above the seabed. For in situ measurements, duplicate readings were made at each water depth at each station. Duplicate water samples were collected at each water depth at each station.
b) Continuous Monitoring of Effluent Quality
2.21. The effluent sampling should be planned carefully to ensure appropriate volume of effluent sub-samples is collected to prepare sufficient amount of flow-weighted composite effluent sample for carrying out subsequent chemical analysis and testing.
Action and Limit Levels
2.22. The Action and Limit Levels have been set based on the derivation criteria specified in the EM&A Manual. The Action/Limit Levels have been derived and are presented in Table 2.7 and Table 2.8.
a) Operation phase Marine Water Quality Monitoring
Table 2.7 Derived Action and Limit Levels for Water Quality
Parameters |
Action |
Limit |
Operation phase
Marine Water Quality
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) |
34.25 PSU
or 9% exceedance of value at any impact station compared with corresponding data from control station |
34.56 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 |
*Anti-scalant in mg/L
(Depth- averaged) |
5.0 mg/L |
5.0 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.
iv. *A proposal for
update anti-scalant monitoring under the operation
phase EM&A programme is proposed via email on 27 May
2024. EPD has agreed to update the anti-scalant
monitoring detection limit, action and limit level from 0.2 mg/L to 5.0 mg/L (EPD ref. ()In EP 2/N8/E/120
Pt.14).
b) Continuous Monitoring of Effluent Quality
Table 2.8 Derived Limit Levels for Water Quality
Parameters |
Limit |
Continuous Monitoring of Effluent Quality |
|
Flow Rate in
m3/day |
216841 |
Temperature in °C |
Maximum 40 |
Salinity |
71347 |
SS in mg/L |
13 |
pH |
6-9 |
Iron in mg/L |
0.6 |
Total residual chlorine in mg/L |
0.1 |
Total Inorganic Nitrogen in mg/L |
2 |
Total Phosphorous in mg/L |
1 |
Sodium Metabisulphite in mg/L |
0.5 |
Anti scalant in mg/L* |
2.2 |
*Remark:
1. Anti-scalant water quality testing
will only be conducted whenever
anti-scalant
dosage is adopted.
Monitoring Results and Observations
a) Operation phase Marine Water Quality Monitoring
2.23. The operation phase of Tseung Kwan O Desalination Plant was commenced on 1 July 2024. Marine water quality monitoring for the operation phase of Tseung Kwan O Desalination Plant was conducted in the reporting period at the thirteen monitoring stations (CE, CF, WSR1, WSR2, WSR3, WSR4, WSR16, WSR33, WSR36, WSR37, NF1, NF2 and NF3). The Action and Limit Level would be referred to the approved EM&A Manual Table 2.7.
2.24. The marine water quality monitoring was conducted at the thirteen monitoring stations on 3, 7, 10, 12, 14, 17, 19, 21, 24, 26 and 28 September 2024.
2.25. Twelve (12) of the operation phase water quality monitoring results of SS obtained had exceeded the Action Level. Twenty (20) of SS obtained during the reporting period had exceeded the Limit Level.
2.26. Investigation on the reason of exceedance has been carried out, where the exceedances of SS on 7, 12, 14, 17, 19, 21, 24, 26 and 28 September 2024 were concluded to be unrelated to the Contract as detailed in the Incident Reports on Action Level or Limit Level Non- compliance along with supporting materials in Appendix K.
2.27. Monitoring results of 8 key parameters: Salinity, DO, turbidity, SS, pH, temperature, Total Residual Chlorine and Iron in this reporting, are summarized in Table 2.9, and detailed results are presented in Appendix F.
b) Continuous Monitoring of Effluent Quality
2.28. Continuous Monitoring of Effluent Quality
was conducted sampling
point in the reporting
month. No exceedance of the sampling was
obtained during the reporting period had exceeded the Limit Level. The detailed
results are summarized in Table 2.10,
and presented in Appendix F.
Table 2.9 Summary of Impact Water Quality Monitoring Results
Locations |
Parameters |
|||||||||
Salinity
(ppt) |
Dissolved Oxygen (mg/L) |
pH |
Turbidity
(NTU) |
Suspended Solids (mg/L) |
Temp. (oC) |
TRC (mg/L) |
Iron (mg/L) |
|||
Surface & Middle |
Bottom |
|||||||||
CE |
Avg. |
32.49 |
8.71 |
8.73 |
8.14 |
2.52 |
3.41 |
28.84 |
<0.01 |
<0.1 |
Min. |
31.63 |
8.12 |
8.04 |
8.03 |
1.98 |
2.50 |
27.94 |
<0.01 |
<0.1 |
|
Max. |
33.66 |
9.54 |
9.58 |
8.27 |
2.85 |
7.00 |
29.85 |
<0.01 |
<0.1 |
|
CF |
Avg. |
32.19 |
8.62 |
8.60 |
8.27 |
2.40 |
3.55 |
28.94 |
<0.01 |
<0.1 |
Min. |
31.20 |
7.91 |
7.92 |
8.12 |
2.13 |
2.00 |
28.02 |
<0.01 |
<0.1 |
|
Max. |
33.55 |
9.57 |
9.51 |
8.40 |
2.96 |
9.00 |
29.98 |
<0.01 |
<0.1 |
|
WSR1 |
Avg. |
31.97 |
8.59 |
8.60 |
8.19 |
1.71 |
3.30 |
28.91 |
<0.01 |
<0.1 |
Min. |
31.33 |
7.81 |
7.80 |
8.08 |
1.32 |
2.50 |
28.14 |
<0.01 |
<0.1 |
|
Max. |
33.09 |
9.08 |
9.13 |
8.31 |
2.10 |
6.00 |
29.69 |
<0.01 |
<0.1 |
|
WSR2 |
Avg. |
32.34 |
8.66 |
8.66 |
8.20 |
1.84 |
3.28 |
28.92 |
<0.01 |
<0.1 |
Min. |
31.54 |
7.52 |
7.53 |
8.05 |
1.52 |
2.50 |
28.12 |
<0.01 |
<0.1 |
|
Max. |
33.17 |
9.66 |
9.72 |
8.32 |
2.17 |
6.00 |
29.74 |
<0.01 |
<0.1 |
|
WSR3 |
Avg. |
32.34 |
8.75 |
8.74 |
8.23 |
1.77 |
3.44 |
28.82 |
<0.01 |
<0.1 |
Min. |
30.93 |
7.54 |
7.58 |
7.98 |
1.45 |
2.50 |
27.85 |
<0.01 |
<0.1 |
|
Max. |
33.59 |
9.46 |
9.57 |
8.39 |
2.21 |
8.00 |
29.80 |
<0.01 |
<0.1 |
|
WSR4 |
Avg. |
32.24 |
8.61 |
8.61 |
8.20 |
1.68 |
3.63 |
28.91 |
<0.01 |
<0.1 |
Min. |
31.27 |
8.08 |
8.15 |
8.10 |
1.34 |
2.50 |
27.88 |
<0.01 |
<0.1 |
|
Max. |
33.62 |
9.27 |
9.36 |
8.28 |
1.96 |
10.00 |
29.74 |
<0.01 |
<0.1 |
|
WSR16 |
Avg. |
32.24 |
8.56 |
8.55 |
8.21 |
1.76 |
3.48 |
28.93 |
<0.01 |
<0.1 |
Min. |
31.21 |
7.68 |
7.73 |
8.06 |
1.34 |
2.50 |
27.88 |
<0.01 |
<0.1 |
|
Max. |
32.97 |
9.52 |
9.39 |
8.40 |
2.10 |
7.00 |
29.83 |
<0.01 |
<0.1 |
Locations |
Parameters |
|||||||||
Salinity
(ppt) |
Dissolved Oxygen (mg/L) |
pH |
Turbidity
(NTU) |
Suspended Solids (mg/L) |
Temp. (oC) |
TRC (mg/L) |
Iron (mg/L) |
|||
Surface & Middle |
Bottom |
|||||||||
WSR33 |
Avg. |
32.29 |
8.66 |
8.66 |
8.26 |
1.72 |
3.52 |
28.93 |
<0.01 |
<0.1 |
Min. |
31.64 |
7.77 |
7.80 |
8.12 |
1.33 |
2.50 |
27.83 |
<0.01 |
<0.1 |
|
Max. |
32.90 |
9.47 |
9.49 |
8.37 |
2.13 |
8.00 |
30.05 |
<0.01 |
<0.1 |
|
WSR36 |
Avg. |
32.27 |
8.44 |
8.45 |
8.22 |
1.82 |
3.64 |
28.97 |
<0.01 |
<0.1 |
Min. |
30.94 |
7.73 |
7.73 |
8.05 |
1.54 |
2.50 |
28.05 |
<0.01 |
<0.1 |
|
Max. |
33.51 |
9.29 |
9.32 |
8.35 |
2.19 |
7.00 |
29.87 |
<0.01 |
<0.1 |
|
WSR37 |
Avg. |
31.88 |
8.56 |
8.59 |
8.22 |
1.77 |
4.25 |
28.93 |
<0.01 |
<0.1 |
Min. |
30.72 |
8.08 |
8.10 |
8.07 |
1.29 |
2.50 |
27.77 |
<0.01 |
<0.1 |
|
Max. |
33.21 |
9.42 |
9.47 |
8.34 |
2.12 |
8.00 |
30.12 |
<0.01 |
<0.1 |
|
NF1 |
Avg. |
32.37 |
8.70 |
8.69 |
8.21 |
1.81 |
3.79 |
28.88 |
<0.01 |
<0.1 |
Min. |
31.55 |
7.87 |
7.81 |
8.02 |
1.58 |
2.50 |
27.99 |
<0.01 |
<0.1 |
|
Max. |
33.04 |
9.54 |
9.42 |
8.32 |
2.08 |
8.00 |
29.70 |
<0.01 |
<0.1 |
|
NF2 |
Avg. |
32.26 |
8.53 |
8.54 |
8.19 |
1.73 |
3.77 |
28.96 |
<0.01 |
<0.1 |
Min. |
31.51 |
7.89 |
7.84 |
8.01 |
1.39 |
2.50 |
27.94 |
<0.01 |
<0.1 |
|
Max. |
32.90 |
9.14 |
9.19 |
8.33 |
2.09 |
7.00 |
29.98 |
<0.01 |
<0.1 |
|
NF3 |
Avg. |
32.18 |
8.79 |
8.82 |
8.21 |
1.66 |
3.83 |
28.93 |
<0.01 |
<0.1 |
Min. |
31.14 |
7.97 |
7.98 |
8.04 |
1.41 |
2.50 |
28.04 |
<0.01 |
<0.1 |
|
Max. |
32.92 |
9.21 |
9.31 |
8.34 |
1.96 |
8.00 |
29.77 |
<0.01 |
<0.1 |
Notes:
i.
"Avg",
“Min” and “Max” is the average,
minimum and maximum respectively of the data from measurements conducted under
mid-flood and mid-ebb tides at three water depths, except that of
DO where the data for “Surface
& Middle” and “Bottom” are calculated separately.
ii.
Measurement data of Suspending Solids
would be rounding
to 2.5mg/L if the value was less than 2.5mg/L
to facilitate data analysing.
Table 2.10 Summary of Continuous Effluent Monitoring Results
|
Sal (ppt) |
pH |
Temp (°C) |
Total
Residual Chlorine (mg/L) |
Suspended Solids (mg/L) |
Total Inorganic Nitrogen (mg/L) |
Total Phosphorus (mg/L) |
*Sodium Metabisulphite
(mg/L) |
Iron (mg/L) |
Avg. |
54.88 |
7.68 |
29.67 |
0.03 |
3.00 |
0.54 |
0.01 |
<2 |
<0.1 |
Min. |
51.05 |
7.27 |
24.50 |
0.00 |
<2 |
0.08 |
<0.01 |
<2 |
<0.1 |
Max. |
58.25 |
7.85 |
31.06 |
0.20 |
2 |
0.49 |
0.02 |
<2 |
<0.1 |
* Remark:
As confirmed by various laboratories in Hong Kong, the lowest detection
limit for Sodium
Metabisulphite is <2 mg/L. Due to the limitation of the laboratory, the lowest result for
Sodium Metabisulphite
will only be shown as < 2 mg/L.
3.1. The waste generated from this Contract includes inert construction and demolition (C&D) materials, and non-inert C&D materials. Non-inert C&D materials are made up of general refuse, vegetative wastes and recyclable wastes such as plastics and paper/cardboard packaging waste. Steel materials generated from the Contract are also grouped into non-inert C&D materials as the materials were not disposed of with other inert C&D materials. With reference to relevant handling records and trip tickets of this Contract, the quantities of different types of waste generated in the reporting month are summarized in Table 3.1. Details of cumulative waste management data are presented as a waste flow table in Appendix G.
Table 3.1 Quantities of Waste Generated from the Contract during the reporting period
Reporting
Month |
Actual Quantities of Inert C&D Materials Generated Monthly |
Actual Quantities of C&D Wastes
Generated Monthly |
|||||||||
Total Quantity Generated |
Hard Rock and Large Broken Concrete |
Reused in the
Contract |
Reused in other Projects |
Disposed as Public Fill |
Imported Fill |
Metals |
Paper / cardboard packaging |
Plastics (1) |
Chemical Waste |
Others, e.g., general refuse |
|
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
(in ’000kg) |
|
Sep 2024 |
834.890 |
0.000 |
0.000 |
0.000 |
834.890 |
0.000 |
0.000 |
0.000 |
0.000 |
0.805 |
27.020 |
Notes: (1) Plastics refer to plastic
bottles / containers, plastic sheets / foam from packaging material
3.2. No dewatered sludge was generated by the operation in the reporting period.
Monitoring Requirement
4.1. In accordance with Section 11 of the EM&A Manual, monthly monitoring of landfill gas is required for the first year of operation at buildings within the Project Site and consultation zone. Part of the desalination plant and the indicative area of natural slope mitigation works fall within the SENT Landfill Extension Consultation Zone; and part of the 1,200 mm diameter freshwater mains along Wan Po Road falls within the SENT Landfill and SENT Landfill Extension Consultation Zones, TKO Stage II/III Restored Landfill and TKO Stage I Restored Landfill Consultation Zones.