5.1 Legislation,
Standards and Guidelines
5.3 Indication
Point and Methodology of Quantitative Modelling
5.4 Construction
Phase Assessment ¡V Land-based Works
5.5 Construction
Phase Assessment ¡V Marine-based
Works
5.6 Operational Phase Assessment
Figure 5.1 Locations
of Water Sensitive Receivers
Appendix
5.1a Location
of Water Control Zones
Appendix
5.1b Location
of HKIA Non-Statutory Water Quality Monitoring Stations
Appendix
5.2a Grid
Properties
Appendix
5.2b Validation
Data of Refined Model
Appendix
5.3 Results
of Pore Water Test
Appendix
5.4a Construction
Methodology
Appendix
5.4b Water
Quality Modeling Results (Construction Phase)
Appendix
5.5 Calculation
of Pollution Inventory due to Project
Appendix
5.6 Hydrodynamic
Modeling Results (Operational Phase)
Appendix
5.7 Water
Quality Modeling Results (Operational Phase)
Appendix 5.8 Sustainable Urban Drainage Systems and Polder Scheme
5.1
Legislation, Standards and Guidelines
5.1.1
Legislation and Guidelines to the Surrounding Waterbodies
Environmental
Impact Assessment Ordinance (EIAO) (Cap. 499)
5.1.1.1
EIAO (Cap. 499) provides the major statutory
framework for the environmental impact assessment in Hong Kong. Under Section 16 of the EIAO, EPD issued
the Technical Memorandum on Environmental Impact Assessment Process (TM-EIAO)
which specifies the assessment methods and criteria for the EIA. Annexes 6 and 14 of the TM-EIAO
stipulate the ¡§Criteria for Evaluating Water Pollution¡¨ and ¡§Guidelines for the
Assessment of Water Pollution¡¨ respectively.
Water Pollution Control Ordinance (Cap. 358)
5.1.1.2
WPCO (Cap 358) provides the major statutory
framework for the protection and control of water quality in Hong Kong. According to the Ordinance and its
subsidiary legislation, the entire Hong Kong waters are divided into ten Water
Control Zones (WCZs) and four supplementary WCZs. Each WCZ has a designated set of
statutory Water Quality Objectives (WQOs). The WQOs set limits for different
parameters that should be achieved in order to protect specific beneficial uses
and conservation goals of each of the zones. The study area is situated within the
Northern WCZ and close to Western Buffer WCZ, which are identified with the
following beneficial uses:
¡P
Nature reserves and Site of Special Scientific
Interest;
¡P
Maintenance of natural ecosystems and
wildlife;
¡P
Production of fish, crustaceans and shellfish
for human consumption;
¡P
Bathing, diving and primary contact
recreation;
¡P
Boating, fishing and secondary contact
recreation;
¡P
Aesthetic enjoyment;
¡P
Industrial and domestic water supply;
¡P
Supply of flushing water;
¡P
Navigation and shipping;
¡P
Typhoon shelter;
¡P
Reception and dilution of effluents.
5.1.1.3
The water quality objectives for the North Western WCZ, North Western
Supplementary WCZ and Western Buffer WCZ are summarized in Table 5.1a, Table 5.1b and Table
5.1c. The location of North Western WCZ, North Western Supplementary WCZ
and Western Buffer WCZ are presented in Appendix 5.1a.
Table
5.1a WQOs of North Western WCZ
Water Quality
Objectives |
Aesthetic Appearance |
•
There should be no
objectionable odours or discolouration of the water; •
Tarry residues,
floating wood, articles made of glass, plastic, rubber or any other
substances should be absent; •
Mineral oil should
not be visible on the surface; •
There should be no
recognisable sewage derived debris; and •
Floating, submerged
and semi-submerged objects of a size likely to interfere with the free
movement of vessels, or cause damage to vessels, should be absent. •
Waste discharges
should not cause the water to contain substances which settle to form
objectionable deposits. |
Bacteria |
•
The levels of E
coli should not exceed 180 counts per 100ml at bathing beaches,
calculated as the geometric mean of all samples collected from March to
October inclusive. Samples have
to be taken at least 3 times a month at intervals of between 3 and 14 days; •
The levels of E
coli should not exceed 610 counts per 100ml at secondary contact
recreation sub-zones, calculated as the geometric annual mean; and •
Waste discharges
shall not cause a risk to any beneficial use of the aquatic environment. |
Dissolved Oxygen |
•
The depth averaged
concentration of dissolved oxygen should not fall below 4 mg/l for 90% of the
sampling occasions during the whole year; and •
The concentration of
dissolved oxygen should not be less than 2 mg/l within 2m of the seabed for
90% of the sampling occasions during the whole year. |
pH |
•
The pH of the water
should be within the range 6.5-8.5 units; and •
Human activity
should not cause the natural pH range to be extended by more than 0.2 units. |
Temperature |
•
Waste discharges
shall not cause the natural daily temperature range to change by more than
2.0¢XC. |
Salinity |
•
Waste Discharges
shall not cause the natural ambient salinity to change by more than 10%. |
Suspended Solids |
•
Human activity
should neither cause the natural ambient level to be raised by more than 30%
nor give rise to accumulation of suspended solids which may adversely affect
aquatic communities. |
Ammonia |
•
The un-ionised ammoniacal nitrogen level should not be more than 0.021
mg/l calculated as the annual average (arithmetic mean). |
Nutrients |
•
Nutrients should not
be present in quantities sufficient to cause excessive or nuisance growth of
algae or other aquatic plants; and •
Without limiting the
generality of the above point, the level of inorganic nitrogen should not
exceed 0.5mg/l in marine waters except Castle Peak sub-zone and 0.3mg/l
within Castle Peak sub-zone, expressed as the annual water column average. |
Toxins |
•
Waste discharges
shall not cause the toxins in water to attain such a level as to produce
significant toxic, carcinogenic, mutagenic or teratogenic
effects in humans, fish or other aquatic organisms, with due regard to
biologically cumulative effects in food chains and to interactions of toxic
substances with each other. |
Table
5.1b WQOs of North Western Supplementary WCZ
Water Quality
Objectives |
Aesthetic Appearance |
•
There should be no
objectionable odours or discolouration of the water; •
Tarry residues,
floating wood, articles made of glass, plastic, rubber or any other
substances should be absent; •
Mineral oil should
not be visible on the surface; •
There should be no
recognisable sewage derived debris; and •
Floating, submerged
and semi-submerged objects of a size likely to interfere with the free
movement of vessels, or cause damage to vessels, should be absent. •
Waste discharges
should not cause the water to contain substances which settle to form
objectionable deposits. |
Bacteria |
•
The level of
Escherichia coli should not exceed 610 per 100 mL, calculated as the
geometric mean of all samples collected in a calendar year. |
Dissolved Oxygen |
•
The depth averaged
concentration of dissolved oxygen should not fall below 4 mg/l for 90% of the
sampling occasions during the whole year; and •
The concentration of
dissolved oxygen should not be less than 2 mg/l within 2m of the seabed for
90% of the sampling occasions during the whole year. |
pH |
•
The pH of the water
should be within the range 6.5-8.5 units; and •
Human activity
should not cause the natural pH range to be extended by more than 0.2 units. |
Temperature |
•
Waste discharges
shall not cause the natural daily temperature range to change by more than
2.0¢XC. |
Salinity |
•
Waste Discharges
shall not cause the natural ambient salinity to change by more than 10%. |
Suspended Solids |
•
Human activity
should neither cause the natural ambient level to be raised by more than 30%
nor give rise to accumulation of suspended solids which may adversely affect
aquatic communities. |
Ammonia |
•
The un-ionised ammoniacal nitrogen level should not be more than 0.021
mg/l calculated as the annual average (arithmetic mean). |
Nutrients |
•
Nutrients should not
be present in quantities sufficient to cause excessive or nuisance growth of
algae or other aquatic plants; and •
Without limiting the
generality of the above point, the level of inorganic nitrogen should not
exceed 0.5mg/l expressed as the annual water column average. |
Toxins |
•
Waste discharges
shall not cause the toxins in water to attain such a level as to produce
significant toxic, carcinogenic, mutagenic or teratogenic
effects in humans, fish or other aquatic organisms, with due regard to
biologically cumulative effects in food chains and to interactions of toxic
substances with each other. |
Table
5.1c WQOs of Western Buffer WCZ
Water Quality
Objectives |
Aesthetic Appearance |
•
There should be no
objectionable odours or discolouration of the water; •
Tarry residues,
floating wood, articles made of glass, plastic, rubber or any other
substances should be absent; •
Mineral oil should
not be visible on the surface; •
There should be no
recognisable sewage derived debris; and •
Floating, submerged
and semi-submerged objects of a size likely to interfere with the free
movement of vessels, or cause damage to vessels, should be absent. •
Waste discharges
should not cause the water to contain substances which settle to form
objectionable deposits. |
Bacteria |
•
The level of
Escherichia coli should not exceed 610 per 100 mL in Secondary Contact
Recreation Subzones and Fish Culture Subzones, calculated as the geometric
mean of all samples collected in a calendar year. •
The level of
Escherichia coli should not exceed 180 per 100 mL in Recreation Subzones,
calculated as the geometric mean of all samples collected from March to
October inclusive in 1 calendar year. Samples should be taken at least 3
times in 1 calendar month at intervals of between 3 and 14 days. •
The level of
Escherichia coli should be less than 1 per 100 mL in Water Gathering Ground
Subzones, calculated as the geometric mean of the most recent 5 consecutive
samples taken at intervals of between 7 and 21 days. |
Dissolved Oxygen |
•
For Marine waters
excepting Fish Culture Subzones, the level of dissolved oxygen should not
fall below 4 mg per litre for 90% of the sampling occasions during the whole
year; values should be calculated as water column average (arithmetic mean of
at least 3 measurements at 1 m below surface, mid-depth and 1 m above
seabed). In addition, the concentration of dissolved oxygen should not be
less than 2 mg per litre within 2 m of the seabed for 90% of the sampling
occasions during the whole year. •
For Fish Culture
Subzones, the level of dissolved oxygen should not be less than 5 mg per
litre for 90% of the sampling occasions during the years; values should be
calculated as water column average (arithmetic mean of at least 3
measurements at 1 m below surface, mid-depth and 1 m above seabed). In
addition, the concentration of dissolved oxygen should not be less than 2 mg
per litre within 2 m of the seabed for 90% of the sampling occasions during
the whole year. |
pH |
•
For Marine waters, the
pH of the water should be within the range 6.5-8.5 units; •
For Water Gathering
Ground Subzones, human activity should not cause the natural pH range to be
extended by more than 0.2 units. |
Temperature |
•
Waste discharges
shall not cause the natural daily temperature range to change by more than
2.0¢XC. |
Salinity |
•
Waste Discharges
shall not cause the natural ambient salinity to change by more than 10%. |
Suspended Solids |
•
Human activity
should neither cause the natural ambient level to be raised by more than 30%
nor give rise to accumulation of suspended solids which may adversely affect
aquatic communities. |
Ammonia |
•
The un-ionised ammoniacal nitrogen level should not be more than 0.021
mg/l calculated as the annual average (arithmetic mean). |
Nutrients |
•
Nutrients should not
be present in quantities sufficient to cause excessive or nuisance growth of
algae or other aquatic plants; and |
•
Without limiting the
generality of the above point, the level of inorganic nitrogen should not
exceed 0.4mg/l, expressed as the annual water column average. |
Toxins |
•
Waste discharges
shall not cause the toxins in water to attain such a level as to produce
significant toxic, carcinogenic, mutagenic or teratogenic
effects in humans, fish or other aquatic organisms, with due regard to
biologically cumulative effects in food chains and to interactions of toxic
substances with each other. |
Technical Memorandum on Standards for
Effluents Discharged into Drainage and Sewerage Systems (TM-DSS)
5.1.1.4
Under Section 21 of the
WPCO (Cap. 385), Technical Memorandum for Effluents Discharged into Drainage
and Sewerage Systems, Inland and Coastal Waters was issued to control the
physical, chemical and microbial quality of effluent discharges into foul
sewers, storm water drains, inland and coastal waters. Specific limits apply for different
areas are different between surface waters and sewers. The limits vary with the effluent flow
rate. Standards for effluent
discharged into the inshore waters and marine waters of North Western WCZ are
summarized in Table 5.2 and Table 5.3.
Table 5.2 Standards for Effluents Discharged into the
Inshore Waters of North Western Control Zones
Flow rate (m3/day) |
≤10 |
>10 and ≤200 |
>200 and ≤400 |
>400 and ≤600 |
>600 and ≤800 |
>800 and ≤1000 |
>1000 and ≤1500 |
>1500 and ≤2000 |
>2000 and ≤3000 |
pH (pH units) |
6-9 |
6-9 |
6-9 |
6-9 |
6-9 |
6-9 |
6-9 |
6-9 |
6-9 |
Temperature (¢XC) |
40 |
40 |
40 |
40 |
40 |
40 |
40 |
40 |
40 |
Colour (lovibond
units) (25mm cell length) |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Suspended solids |
50 |
30 |
30 |
30 |
30 |
30 |
30 |
30 |
30 |
BOD |
50 |
20 |
20 |
20 |
20 |
20 |
20 |
20 |
20 |
COD |
100 |
80 |
80 |
80 |
80 |
80 |
80 |
80 |
80 |
Oil & Grease |
30 |
20 |
20 |
20 |
20 |
20 |
20 |
20 |
20 |
Iron |
15 |
10 |
10 |
7 |
5 |
4 |
3 |
2 |
1 |
Boron |
5 |
4 |
3 |
2 |
2 |
1.5 |
1.1 |
0.8 |
0.5 |
Barium |
5 |
4 |
3 |
2 |
2 |
1.5 |
1.1 |
0.8 |
0.5 |
Mercury |
0.1 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
Cadmium |
0.1 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
Other toxic metals individually |
1 |
1 |
0.8 |
0.7 |
0.5 |
0.4 |
0.3 |
0.2 |
0.15 |
Total toxic metals |
2 |
2 |
1.6 |
1.4 |
1 |
0.8 |
0.6 |
0.4 |
0.3 |
Cyanide |
0.2 |
0.1 |
0.1 |
0.1 |
0.1 |
0.1 |
0.05 |
0.05 |
0.03 |
Phenols |
0.5 |
0.5 |
0.5 |
0.3 |
0.25 |
0.2 |
0.1 |
0.1 |
0.1 |
Sulphide |
5 |
5 |
5 |
5 |
5 |
5 |
2.5 |
2.5 |
1.5 |
Total residual chlorine |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Total nitrogen |
100 |
100 |
80 |
80 |
80 |
80 |
50 |
50 |
50 |
Total phosphorus |
10 |
10 |
8 |
8 |
8 |
8 |
5 |
5 |
5 |
Surfactants (total) |
20 |
15 |
15 |
15 |
15 |
15 |
10 |
10 |
10 |
E. coli (count/100ml) |
1000 |
1000 |
1000 |
1000 |
1000 |
1000 |
1000 |
1000 |
1000 |
Note:
All units in mg/L unless otherwise stated; all
figures are upper limits unless otherwise indicated.
Table 5.3 Standards for Effluents Discharged into the Marine
Waters of North Western Control Zone
Flow rate (m3/day) |
≤10 |
>10 and ≤200 |
>200 and ≤400 |
>400 and ≤600 |
>600 and ≤800 |
>800 and ≤1000 |
>1000 and ≤1500 |
>1500 and ≤2000 |
>2000 and ≤3000 |
pH (pH units) |
6-10 |
6-10 |
6-10 |
6-10 |
6-10 |
6-10 |
6-10 |
6-10 |
6-10 |
Temperature (¢XC) |
45 |
45 |
45 |
45 |
45 |
45 |
45 |
45 |
45 |
Colour (lovibond
units) (25mm cell length) |
4 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Suspended solids |
500 |
500 |
500 |
300 |
200 |
200 |
100 |
100 |
50 |
BOD |
500 |
500 |
500 |
300 |
200 |
200 |
100 |
100 |
50 |
COD |
1000 |
1000 |
1000 |
700 |
500 |
400 |
300 |
200 |
150 |
Oil & Grease |
50 |
50 |
50 |
30 |
25 |
20 |
20 |
20 |
20 |
Iron |
20 |
15 |
13 |
10 |
7 |
6 |
4 |
3 |
2 |
Boron |
6 |
5 |
4 |
3.5 |
2.5 |
2 |
1.5 |
1 |
0.7 |
Barium |
6 |
5 |
4 |
3.5 |
2.5 |
2 |
1.5 |
1 |
0.7 |
Mercury |
0.1 |
0.1 |
0.1 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
Cadmium |
0.1 |
0.1 |
0.1 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
0.001 |
Other toxic metals individually |
2 |
1.5 |
1.2 |
0.8 |
0.6 |
0.5 |
0.32 |
0.24 |
0.16 |
Total toxic metals |
4 |
3 |
2.4 |
1.6 |
1.2 |
1 |
0.64 |
0.48 |
0.32 |
Cyanide |
1 |
0.5 |
0.5 |
0.5 |
0.4 |
0.3 |
0.2 |
0.15 |
0.1 |
Phenols |
0.5 |
0.5 |
0.5 |
0.3 |
0.25 |
0.2 |
0.13 |
0.1 |
0.1 |
Sulphide |
5 |
5 |
5 |
5 |
5 |
5 |
2.5 |
2.5 |
1.5 |
Total residual chlorine |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Total nitrogen |
100 |
100 |
80 |
80 |
80 |
80 |
50 |
50 |
50 |
Total phosphorus |
10 |
10 |
8 |
8 |
8 |
8 |
5 |
5 |
5 |
Surfactants (total) |
30 |
20 |
20 |
20 |
15 |
15 |
15 |
15 |
15 |
E. coli
(count/100ml) |
4000 |
4000 |
4000 |
4000 |
4000 |
4000 |
4000 |
4000 |
4000 |
Note:
All units in mg/L unless
otherwise stated; all figures are upper limits unless otherwise indicated.
ProPECC PN 1/94 ¡§Construction Site Drainage¡¨
5.1.1.5
Professional Persons
Environmental Consultative Committee Practice Notes (ProPECC
PN1/94) on Construction Site Drainage provides guidelines for the handling and
disposal of construction discharges. This note is applicable for control of
site runoff and wastewater generated during the construction phase of the
Project.
5.1.1.6
The types of discharges from construction
sites outlined in the ProPECC PN1/94 that are relevant to this study would include:
¡P
Surface run-off;
¡P
Boring and drilling water;
¡P
Wastewater from concrete batching and precast
concrete casting;
¡P
Wheel washing water; and
¡P
Wastewater from construction activities and
site facilities.
WSD Water Quality Criteria for Salt Water Intakes
5.1.1.7
The criteria for assessing the water quality impact on the Water
Supplies Department (WSD) seawater intakes are based on the Water Quality
Criteria of Seawater for Flushing Supply (at intake point) issued by the WSD
and are summarized in Table 5.4a.
Table
5.4a WSD
Water Quality Criteria for Salt Water Intakes
Parameter |
Concentration |
Colour |
< 20 H.U. |
Turbidity |
< 10
N.T.U. |
Threshold
Odour No. |
< 100 |
Ammonia
Nitrogen |
< 1 mg/l |
Suspended
Solids |
< 10 mg/l |
Dissolved Oxygen |
> 2 mg/l |
Biochemical
Oxygen Demand |
< 10 mg/l |
Synthetic
Detergents |
< 5 mg/l |
E. coli. |
< 20,000 cfu/100 ml |
Water
Quality Criteria for Seawater Intakes in Castle Peak Power Station and Black
Point Power Station
5.1.1.8
As advised by the relevant operator, the criteria for assessing the
water quality impact on the cooling seawater intakes in Castle Peak Power
Station and Black Point Power Station are summarized in Table 5.4b.
Table
5.4b Salt
Water Criteria for Salt Water Intakes at Castle Peak Power Station and Black
Point Power Station
Parameter |
Level |
Temp |
17-30 degC |
Suspended
Solids |
< 764 mg/l
(<700 mg/l for SS elevation) |
5.1.2
Other Guidelines and
Criteria
Assessment Criteria
for Heavy Metals and Trace Organics
5.1.2.1
There is no existing
legislation or guideline for heavy metals and trace organics (PCBs and PAHs) in
Hong Kong waters. According to the common practices in previous EIA studies,
conservative criteria were set out by comparing different countries standards such
as EU, USA, UK and Australia. The lowest values from various international
standards have been adopted as the assessment criteria. The adopted criteria for heavy metals
and trace organics are presented in Table
5.5.
Table
5.5: Proposed
Assessment Criteria for Heavy Metal and Trace Organics
Heavy Metal/Trace Organics |
Proposed Criteria (mg/l) |
Reference |
Arsenic |
25 |
1 |
Cadmium |
0.2 |
2 |
Chromium |
15 |
1 |
Copper |
3.1 |
3 |
Lead |
7.2 |
2 |
Mercury |
0.05 |
2 |
Nickel |
8.2 |
3 |
Silver |
1.9 |
4 |
Zinc |
10 |
1 |
Total PAHs |
3.0 |
6 |
PCBs |
0.03 |
3 |
References:
[1] UK Council Directive on the
quality required of shellfish waters (Shellfish Waters Directive), http://evidence.environment-agency.gov.uk/ChemicalStandards/ChemicalsByName.aspx
[2] Directive
2008/105/EC of the European Parliament and of the Council of 16 December 2008
on environmental
quality standards in the field of water (2008/105/EC),
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:348:0084:0097:EN:PDF
[3] The
USEPA Criterion Continuous Concentration (CCC)
[4]
The USEPA Criteria
Maximum Concentration (CMC)
[6] Total PAH consist of the combination of individual components
including acenaphthene, acenaphthylene,
anthracene, fluorene,
naphthalene, phenanthrene, benzo[a]anthracene, benzo[a]pyrene, chrysene, dibenzo]a,h]anthracene, fluoranthene, pyrene, benzo[b]fluoranthene, benzo[k] fluoranthen, indeno[1,2,3-c,d]pyrene and benzo[g,h,i]perylene.
According to Australian Water Quality Guidelines for Fresh and Marine Waters,
the criterion of naphthalene is 3.0 µg/L for fresh water
aquatic ecosystem conservations.
[7] According to Australian Water Quality Guidelines for Fresh and
Marine Waters, the criterion of copper is 5.0 µg/L for
irrigation and aquaculture purpose.
Tolerant Deposition
Rate for Benthic Ecology
5.1.2.2
Deposition of fine
sediment in ecologically sensitive areas including coral sites could have
adverse impact on the marine ecosystem. In previous studies[1],[2],[3], an indicator level above which sustained deposition could harm
sediment sensitive hermatypic corals of 200g/m2/day
has been used. Typical soft corals in the north western coastal waters where
the sediment regime is more dynamic than in other parts of Hong Kong¡¦s coastal waters, are expected to be more tolerant to sediment deposition.
Hence, criterion of 200g/m2/day would be adopted for this
Study.
5.2.1
Assessment Area
5.2.1.1
In accordance with
Clause 3.4.3.2 of the EIA Study Brief, water quality impact assessment has been
carried out in the study area covering the North Western, North Western
Supplementary and Western Buffer WCZs. The study area is shown in Figure 1.1.
5.2.2
Hydrological
Conditions
5.2.2.1
The North Western
waters are situated in the Pearl River Estuary and are heavily influenced by
the massive freshwater flows from Guangdong Province. Ebb tide currents are
towards the southeast whilst the flood tide currents
to the northwest. The area shows a
distinct seasonality as a result of the seasonal influx of freshwater from
Pearl River. The estuarine
influence is especially pronounced in the wet season when the freshwater flows
are greatest. Moreover, strong salinity and temperature stratification are observed. During dry season, water conditions are
more typical. Salinity and other
parameters vary less with depth.
5.2.2.2
The proposed
development is located to the south of BCF Island. According to HZMB EIAs
studies (AEIAR-145/2009, AEIAR-144/2009), the peak current velocities in Urmston Road could be up to more than 1.3 m/s, whilst the
current in the areas near to the project area have been predicted to be less
than 0.4 m/s.
5.2.2.3
The catchment of Tung
Chung Stream covers Pak Kung Au, Tei Tong Tsai and
east of Ngong Ping. Tung Chung Stream is mainly
natural, except for an engineered channel sections along Shek
Lau Po in east tributary. According to 2014 EPD¡¦s monitoring data, the average flow
rates for west and east tributaries are 43 L/s and 53 L/s at TC1 and TC2
monitoring stations respectively.
5.2.2.4
Tung Chung Bay is
located between the mouth of Tung Chung Stream and Airport Channel. On comparing
to the tidal current at Airport Channel, the water flow of runoff from Tung
Chung Stream is considered negligible.
5.2.2.5
Tai Ho Bay is located
at the mouth of Tai Ho Stream and to the south of the Siu
Ho Wan MTR Depot. The bay is currently connected to the open sea via an opening
of approximately 20m wide underneath a short section of deck of NLH. The runoff from Tai Ho Stream is
relatively small when compared to the tidal current along Urmston
Road or to the south of HKBCF Island.
Hence, Tai Ho Bay has an engulfed bayshore
hydrological regime controlled by tidal variation at the 20m wide opening.
5.2.3
Summary of Latest
Baseline Water Quality Data
5.2.3.1
The Pearl River
carries heavy loads of suspended sediment and nutrients. The concentrations of
these parameters within North Western waters are generally higher than those in
the southern or eastern of Hong Kong waters in which oceanic influence is more
pronounced.
5.2.3.2
The latest water
quality monitoring data in 2014 was adopted to determine the ambient water
quality. Details of marine water quality monitoring data are presented in Table 5.6a and Table 5.6b. According to the Marine Water Quality in Hong Kong 2014,
the North Western WCZ attained an overall WQO compliance rate of 61% in 2014 as
compared with 72% in 2013. The Western Buffer WCZ attained an overall WQO
compliance rate of 83% in 2014 as compared with 92% in 2013. The main reason
for non-compliance was due to the high concentration of TIN which was
associated with the higher background nutrient level in the Pearl River
Delta.
Table 5.6a Summary of EPD¡¦s Routine Marine Water Quality Data for North Western Water Quality Control Zone in 2014
Parameters |
North
Western WCZ [1][2] |
||||||
NM1 |
NM2 |
NM3 |
NM5 |
NM6 |
NM8 |
||
Temperature
(¢XC) |
23.4 |
23.9 |
23.9 |
24.0 |
24.3 |
23.8 |
|
(17.2
- 28.9) |
(17.2
- 29.0) |
(17.3
- 28.9) |
(17.3
- 29.0) |
(17.1
- 30.2) |
(17.1
- 29.0) |
||
Salinity |
30.2 |
28.3 |
28.0 |
27.1 |
25.3 |
28.5 |
|
(25.2
- 32.3) |
(19.5
- 32.4) |
(19.7
- 32.4) |
(20.4
- 32.2) |
(10.1
- 32.5) |
(18.6
- 32.9) |
||
Dissolved
Oxygen (mg/L) |
Depth
Average |
5.6 |
5.8 |
5.8 |
5.7 |
6.3 |
6.2 |
(3.2
- 8.5) |
(3.8
- 8.3) |
(3.8
- 9.0) |
(3.9
- 9.8) |
(4.4
- 8.3) |
(4.3
- 9.0) |
||
Bottom |
5.4 |
5.7 |
5.7 |
5.6 |
6.3 |
5.8 |
|
(1.9
- 9.5) |
(3.2
- 9.5) |
(2.9
- 9.9) |
(2.8
- 9.5) |
(4.2
- 9.2) |
(0.8
- 9.4) |
||
Dissolved
Oxygen (% Saturation) |
Depth
Average |
77 |
80 |
80 |
77 |
86 |
85 |
(46
- 108) |
(55
- 106) |
(55
- 114) |
(57
- 125) |
(63
- 107) |
(62
- 115) |
||
Bottom |
75 |
79 |
79 |
77 |
86 |
80 |
|
(27
- 121) |
(47
- 120) |
(42
- 126) |
(41
- 121) |
(61
- 116) |
(12
- 121) |
||
pH |
7.9 |
7.9 |
7.9 |
7.8 |
7.9 |
8.0 |
|
(7.6
- 8.0) |
(7.5 - 8.1) |
(7.5 - 8.1) |
(7.4 - 8.1) |
(7.4 - 8.1) |
(7.6 - 8.1) |
||
Secchi Disc Depth
(m) |
2.8 |
2.5 |
2.5 |
2.3 |
2.2 |
2.1 |
|
(1.6
- 5.0) |
(1.0 - 5.0) |
(1.3 - 5.0) |
(1.4 - 4.5) |
(1.2 - 4.0) |
(1.2 - 3.0) |
||
Turbidity
(NTU) |
4.8 |
3.6 |
5.8 |
6.3 |
7.0 |
7.3 |
|
(0.7
- 17.0) |
(1.0 - 7.9) |
(0.9 - 20.3) |
(2.3 - 14.7) |
(1.2 - 28.8) |
(3.0 - 14.3) |
||
SS
(mg/L) |
6.6 |
4.3 |
7.6 |
6.8 |
8.6 |
9.0 |
|
(1.1
- 25.7) |
(1.5 - 12.3) |
(2.0 - 30.0) |
(2.8 - 20.7) |
(2.6 - 44.0) |
(2.1 - 26.7) |
||
5-day
Biochemical Oxygen Demand (mg/L) |
0.7 |
0.8 |
0.8 |
0.8 |
1.0 |
0.8 |
|
(0.4
- 1.7) |
(0.4
- 1.8) |
(0.4
- 2.1) |
(0.4
- 2.1) |
(0.4
- 2.0) |
(0.4
- 1.5) |
||
Ammonia
Nitrogen (mg/L) |
0.093 |
0.107 |
0.108 |
0.122 |
0.091 |
0.041 |
|
(0.031
- 0.176) |
(0.014 - 0.260) |
(0.006 - 0.277) |
(0.005 - 0.297) |
(<0.005 - 0.243) |
(0.006 - 0.094) |
||
Unionised
Ammonia (mg/L) |
0.003 |
0.003 |
0.003 |
0.004 |
0.003 |
0.002 |
|
(0.001
- 0.006) |
(<0.001 - 0.008) |
(<0.001 - 0.008) |
(<0.001 - 0.008) |
(<0.001 - 0.008) |
(<0.001 - 0.004) |
||
Nitrite
Nitrogen (mg/L) |
0.058 |
0.081 |
0.091 |
0.108 |
0.108 |
0.067 |
|
(0.023
- 0.115) |
(0.024 - 0.233) |
(0.022 - 0.263) |
(0.022 - 0.323) |
(0.016 - 0.270) |
(0.011 - 0.163) |
||
Nitrate
Nitrogen (mg/L) |
0.268 |
0.394 |
0.426 |
0.48 |
0.544 |
0.364 |
|
(0.067
- 0.603) |
(0.051 - 0.967) |
(0.056 - 0.997) |
(0.047 - 1.010) |
(0.044 - 1.370) |
(0.014 - 1.180) |
||
Total
Inorganic Nitrogen (mg/L) |
0.42 |
0.58 |
0.63 |
0.71 |
0.74 |
0.47 |
|
(0.15
- 0.71) |
(0.12 - 1.13) |
(0.14 - 1.18) |
(0.13 - 1.26) |
(0.10 - 1.51) |
(0.04 - 1.28) |
||
Total
Kjeldahl Nitrogen (mg/L) |
0.27 |
0.30 |
0.29 |
0.31 |
0.28 |
0.20 |
|
(0.18
- 0.41) |
(0.17 - 0.44) |
(0.17 - 0.42) |
(0.19 - 0.47) |
(0.14 - 0.44) |
(0.13 - 0.35) |
||
Total
Nitrogen (mg/L) |
0.59 |
0.78 |
0.81 |
0.89 |
0.93 |
0.63 |
|
(0.36
- 0.86) |
(0.33 - 1.32) |
(0.33 - 1.40) |
(0.31 - 1.48) |
(0.25 - 1.72) |
(0.21 - 1.47) |
||
Orthophosphate
Phosphorus (mg/L) |
0.021 |
0.023 |
0.025 |
0.028 |
0.022 |
0.015 |
|
(0.010
- 0.032) |
(0.008 - 0.041) |
(0.008 - 0.043) |
(0.008 - 0.050) |
(0.006 - 0.041) |
(0.006 - 0.030) |
||
Total
Phosphorus (mg/L) |
0.04 |
0.04 |
0.04 |
0.05 |
0.04 |
0.03 |
|
(<0.02
- 0.07) |
(<0.02 - 0.05) |
(<0.02 - 0.06) |
(<0.02 - 0.06) |
(<0.02 - 0.07) |
(<0.02 - 0.06) |
||
Silica
(as SiO2) (mg/L) |
1.59 |
2.08 |
2.23 |
2.42 |
2.71 |
1.93 |
|
(<0.05
- 3.33) |
(<0.05 - 4.60) |
(<0.05 - 4.80) |
(0.05 - 4.93) |
(0.05 - 6.53) |
(0.05 - 5.87) |
||
Chlorophyll-a
(£gg/L) |
2 |
2.3 |
2.7 |
3.3 |
3.8 |
3.8 |
|
(0.4
- 6.4) |
(0.3 - 7.1) |
(0.3 - 11.0) |
(0.3 - 14.3) |
(0.5 - 13.7) |
(0.3 - 12.3) |
||
E.coli
(count/100mL) |
300 |
71 |
110 |
190 |
22 |
3 |
|
(36
- 2200) |
(7 - 850) |
(8 - 1100) |
(10 - 4100) |
(4 - 180) |
(<1 - 11) |
||
Faecal
Coliforms (count/100mL) |
570 |
150 |
230 |
400 |
48 |
7 |
|
(99
- 3900) |
(24 - 1500) |
(18 - 2300) |
(16 - 6800) |
(6 - 260) |
(1 - 35) |
Notes:
[1] Data
presented are depth averaged and are the annual arithmetic mean except for E. coli (geometric mean).
[2] Data
in brackets indicate ranges.
[3] Extracted
from EPD Marine Water Quality in Hong Kong 2014
Table 5.6b Summary of EPD¡¦s Routine Marine Water Quality Data for Western Buffer Water Quality Control Zone in 2014
Parameters |
Western
Buffer WCZ [1][2] |
||||
WM1 |
WM2 |
WM3 |
WM4 |
||
Temperature
(¢XC) |
23 |
23.3 |
23.2 |
23.2 |
|
(16.4
- 28.8) |
(16.5 - 28.7) |
(16.6 - 28.8) |
(16.4 - 28.8) |
||
Salinity |
32.7 |
31.9 |
31.8 |
31.7 |
|
(31.0
- 33.5) |
(29.3 - 33.3) |
(29.4 - 33.1) |
(28.7 - 33.2) |
||
Dissolved
Oxygen (mg/L) |
Depth
Average |
6.2 |
5.9 |
5.7 |
5.5 |
(3.1
- 7.7) |
(3.2 - 8.0) |
(3.5 - 7.4) |
(3.1 - 7.0) |
||
Bottom |
6.2 |
6.1 |
5.9 |
5.8 |
|
(2.5
- 8.2) |
(3.0 - 8.0) |
(2.6 - 7.8) |
(2.5 - 7.9) |
||
Dissolved
Oxygen (% Saturation) |
Depth
Average |
87 |
82 |
80 |
76 |
(45
- 101) |
(47 - 100) |
(51 - 94) |
(46 - 90) |
||
Bottom |
87 |
85 |
82 |
81 |
|
(35
- 105) |
(43 - 103) |
(38 - 99) |
(36 - 99) |
||
pH |
7.9 |
7.9 |
7.9 |
7.9 |
|
(7.7
- 8.2) |
(7.6 - 8.2) |
(7.6 - 8.1) |
(7.6 - 8.2) |
||
Secchi Disc Depth
(m) |
3.2 |
3.1 |
2.7 |
2.8 |
|
(1.5
- 5.0) |
(1.6 - 4.5) |
(2.0 - 4.0) |
(1.7 - 4.0) |
||
Turbidity
(NTU) |
3.7 |
2.6 |
3.8 |
4.7 |
|
(1.0
- 6.7) |
(1.0 - 4.6) |
(1.5 - 7.6) |
(1.6 - 14.6) |
||
SS
(mg/L) |
5 |
3.7 |
5.4 |
6.6 |
|
(1.6
- 16.0) |
(1.6 - 11.3) |
(2.3 - 15.3) |
(2.1 - 16.0) |
||
5-day
Biochemical Oxygen Demand (mg/L) |
0.6 |
0.7 |
0.7 |
0.7 |
|
(0.3
- 1.2) |
(0.3 - 1.1) |
(0.3 - 1.1) |
(0.3 - 2.9) |
||
Ammonia
Nitrogen (mg/L) |
0.039 |
0.093 |
0.135 |
0.108 |
|
(0.011
- 0.086) |
(0.024 - 0.180) |
(0.045 - 0.270) |
(0.038 - 0.210) |
||
Unionised
Ammonia (mg/L) |
0.001 |
0.003 |
0.004 |
0.003 |
|
(<0.001
- 0.004) |
(<0.001 - 0.006) |
(0.001 - 0.009) |
(<0.001 - 0.007) |
||
Nitrite
Nitrogen (mg/L) |
0.018 |
0.031 |
0.033 |
0.038 |
|
(0.004
- 0.033) |
(0.005 - 0.091) |
(0.006 - 0.079) |
(0.005 - 0.101) |
||
Nitrate
Nitrogen (mg/L) |
0.071 |
0.132 |
0.141 |
0.161 |
|
(0.010
- 0.137) |
(0.036 - 0.310) |
(0.043 - 0.313) |
(0.047 - 0.333) |
||
Total
Inorganic Nitrogen (mg/L) |
0.13 |
0.26 |
0.31 |
0.31 |
|
(0.05
- 0.22) |
(0.13 - 0.42) |
(0.17 - 0.48) |
(0.17 - 0.51) |
||
Total
Kjeldahl Nitrogen (mg/L) |
0.25 |
0.24 |
0.3 |
0.26 |
|
(0.09
- 1.14) |
(0.14 - 0.33) |
(0.18 - 0.47) |
(0.14 - 0.40) |
||
Total
Nitrogen (mg/L) |
0.34 |
0.41 |
0.48 |
0.45 |
|
(0.16
- 1.27) |
(0.29 - 0.57) |
(0.29 - 0.68) |
(0.30 - 0.69) |
||
Orthophosphate
Phosphorus (mg/L) |
0.012 |
0.017 |
0.021 |
0.019 |
|
(0.006
- 0.017) |
(0.007 - 0.025) |
(0.010 - 0.033) |
(0.006 - 0.027) |
||
Total
Phosphorus (mg/L) |
0.02 |
0.03 |
0.04 |
0.04 |
|
(<0.02
- 0.04) |
(0.02 - 0.05) |
(0.03 - 0.05) |
(0.03 - 0.05) |
||
Silica
(as SiO2) (mg/L) |
0.77 |
1.03 |
1.09 |
1.17 |
|
(0.12
- 1.60) |
(0.12 - 2.43) |
(0.14 - 2.37) |
(0.11 - 2.70) |
||
Chlorophyll-a
(£gg/L) |
2.7 |
2.8 |
2.2 |
2.2 |
|
(0.9
- 7.3) |
(0.4 - 9.3) |
(0.5 - 11.1) |
(0.2 - 11.6) |
||
E.coli
(count/100mL) |
66 |
160 |
580 |
170 |
|
(13
- 340) |
(5 - 7800) |
(86 - 4000) |
(77 - 300) |
||
Faecal
Coliforms (count/100mL) |
150 |
300 |
1200 |
340 |
|
(45
- 550) |
(6 - 15000) |
(200 - 9200) |
(160 - 700) |
Notes:
[1] Data
presented are depth averaged and are the annual arithmetic mean except for E.
coli (geometric mean).
[2] Data
in brackets indicate ranges.
[3] Extracted
from EPD Marine Water Quality in Hong Kong 2013
5.2.3.3
EPD also conducts routine river quality monitoring
in Hong Kong. Tung Chung Stream is
the major river closest to the assessment area. Figure
5.1 shows
three EPD river monitoring stations (TC1, TC2 and TC3) in Tung Chung Stream.
According to the River Water Quality in Hong Kong 2013, the WQO compliance for
Tung Chung Stream reached 99%, higher than that for year 2012 which was 97%.
Details of Tung Chung Stream water quality monitoring data is presented in Table 5.7.
5.2.3.4
The EPD sea bottom sediment quality monitoring
data in the North Western and Western Buffer WCZs are presented in Table 5.8 and Table 5.9 respectively. According to EPD Marine Water Quality
Report 2013, the levels of toxic substance in marine water met local and
international levels for protection of marine life and human health.
5.2.3.5
A summary of beach water quality monitoring
data routinely monitored by EPD at relevant monitoring stations is presented in
Table 5.10 and Table 5.11. All 41 gazetted beaches in Hong Kong complied with the
WQO in 2013. The E. coli count in the
Tuen Mun District ranged
from 39 to 78 counts per 100ml in 2013. All the beaches along the Tuen Mun coast received ¡§Fair¡¨
annual ranking. The E. coli count in
the Tsuen Wan District ranged from 41 to 135 counts
per 100ml in 2013. All the beaches along the Tsuen Wan
area received ¡§Fair¡¨ annual ranking. Besides, the annual E.coli levels at the eight Tsuen Wan beaches have dropped and met the WQO since Year
2010 as a result of the operation of the Advanced Disinfection Facilities at
Stonecutters Island STW.
Pore Water Test Results from
Present Study
5.2.3.6
Sediment samples were collected at the
proposed site of reclamation. Pore water tests were conducted
for the following parameters:
¡P
Heavy metals and metalloid including cadmium,
chromium, copper, mercury, nickel, lead, zinc, silver and arsenic;
¡P
Organic micro-pollutants including PCB, PAH, Organichlorine Pesticides (OC); and
¡P
NO3-N, NO2-N, NH3-N, total phosphorus, Reactive Phosphorus.
5.2.3.7
The Pore Water Test Results for the present study
are summarized in Table 5.12. The
sampling locations and details are presented in Appendix 5.3. TIN will be
estimated based on the measurement results of NO3-N, NO2-N,
and NH3-N. UIA will be estimated based on the measurement results of
NH3-N. As shown in Appendix 5.3, Organichlorine Pesticides (OC) have been measured in pore water test. They were below
detection limit.
5.2.3.8
The results of Pore Water Test are checked
against the heavy metals and nutrients criteria presented in Table 5.5. The parameters that exceed
the water quality criteria include:
Pore Water Test: As, TIN and NH3-N.
Subject to the water quality modelling result at the sensitive receivers, during
construction phase, mitigation measures may be required to minimize the release
of contaminants.
Non-Statutory Marine
Environmental Monitoring for Hong Kong International Airport
5.2.3.9
The Airport Authority Hong
Kong has conducted four rounds of monitoring since 2002. According to the 3RS
EIA, a non-statutory marine environmental monitoring update for the marine
environment surrounding HKIA, including the Southern Sea Channel and East Tung
Chung Bay, was carried out. The study consisted of marine water quality
monitoring and marine sediment quality monitoring. The marine water quality
information provides a useful comparison as the monitoring locations in that study
are much closer to the boundary of the present study.
5.2.3.10 According to the 3RS EIA, water quality monitoring survey has been carried out between November 2002 and January 2011. The water quality monitoring locations are shown in Appendix 5.1b. The water quality monitoring results are presented in Table 5.13.
5.2.3.11 The marine water quality monitoring results indicated that most of the water quality parameters recorded at their Control and Impact Stations would generally comply with the relevant North Western WCZ WQOs, except for TIN. There are some irregular exceedance in salinity, DO and SS during 2003-2011. For TIN, exceedance were observed in wet season, which may be due to the influence from Pearl River.
Water Quality Monitoring
for New CMPs at East of Sha Chau
5.2.3.12 Routine water quality monitoring has been conducted by CEDD throughout the operation of the Contaminated Mud Pits at Airport East / East Sha Chau. The monitoring is conducted at a frequency of once per quarter and at three monitoring locations. When comparing the results with the SS criteria (30 % of the 90th percentile at the nearest EPD monitoring station) set in Table 5.18 for NM3 and NM6, it was observed that all SS elevations would comply with the WQO criteria. The water quality monitoring data is summarized in Table 5.14.
5.2.3.13 Water quality monitoring has also been conducted during the construction works for the Contaminated Mud Pit V at East of Sha Chau. Water quality monitoring was commenced in September 2009. The monitoring was conducted at three water depths (surface, mid-depth and bottom) at a frequency of three days per week, under mid-flood and mid-ebb tides. The results are shown in Table 5.15. In general, the impact water quality monitoring results for impact station complied with the North Western WCZ WQOs.
Table 5.7 Summary of EPD¡¦s routine river water
quality data at Tung Chung Stream in 2014
Parameter |
Tung Chung Stream
[1][2][5] |
||
TC1 |
TC2 |
TC3 |
|
Dissolved oxygen (mg/L) |
7.9 |
8.1 |
8.3 |
(7.4-9.8) |
(7.5-11.0) |
(7.8-10.2) |
|
pH |
6.9 |
7.3 |
7.8 |
(6.7-7.4) |
(6.9-8.1) |
(6.7-8.3) |
|
SS (mg/L) |
1 |
3 |
2 |
(<1-6) |
(1-5) |
(<1-12) |
|
5-day Biochemical Oxygen Demand (mg/L) |
<1 |
<1 |
5 |
(<1-<1) |
(<1-2) |
(<1-23) |
|
Chemical Oxygen Demand (mg/L) |
<2 |
4 |
7 |
(<2-6) |
(<2-11) |
(<2-20) |
|
Oil & grease (mg/L) |
<0.5 |
<0.5 |
<0.5 |
(<0.5-0.8) |
(<0.5-0.8) |
(<0.5-1.0) |
|
Faecal coliforms (cfu/100mL) |
510 |
4,400 |
61,000 |
(15-13,000) |
(430-42,000) |
(22,000 - 140,000)
|
|
E. coli(cfu/100mL)[4] |
48 |
79 |
15,000 |
(7-2,000) |
(12-2,700) |
(2,000-71,000) |
|
Ammonia-nitrogen (mg/L) |
0.01 |
0.02 |
0.64 |
(<0.01-0.13) |
(<0.01-0.03) |
(0.07-1.60) |
|
Nitrate-nitrogen (mg/L) |
0.06 |
0.01 |
0.10 |
(0.01-0.29) |
(<0.01-0.24) |
(0.05-0.24) |
|
Total Kjeldahl nitrogen (mg/L) |
0.12 |
0.14 |
1.10 |
(<0.05-0.27) |
(<0.07-0.28) |
(0.21-2.60) |
|
Ortho-phosphate (mg/L) |
<0.01 |
<0.01 |
0.06 |
(<0.01-0.04) |
(<0.01-0.02) |
(0.01-0.18) |
|
Total phosphorus (mg/L) |
<0.02 |
<0.02 |
0.11 |
(<0.02-0.05) |
(<0.02-0.04) |
(<0.02-0.35) |
|
Total sulphide (mg/L) |
<0.02 |
<0.02 |
<0.02 |
(<0.02-<0.02) |
(<0.02-<0.02) |
(<0.02-<0.02) |
|
Aluminium (µg/L) |
<50 |
<50 |
<50 |
(<50-164) |
(<50-120) |
(<50-134) |
|
Cadmium (µg/L) |
<0.1 |
<0.1 |
<0.1 |
(<0.1-<0.1) |
(<0.1-<0.1) |
(<0.1-<0.1) |
|
Chromium (µg/L) |
<1 |
<1 |
<1 |
(<1-<1) |
(<1-1) |
(<1-1) |
|
Copper (µg/L) |
<1 |
<1 |
1 |
(<1-2) |
(<1-3) |
(<1-5) |
|
Lead (µg/L) |
<1 |
<1 |
<1 |
(<1-1) |
(<1-1) |
(<1-3) |
|
Zinc (µg/L) |
13 |
<14 |
10 |
(<10-24) |
(<10-33) |
(<10-38) |
|
Flow (L/s) |
43 |
53 |
NM [3] |
(12-160) |
(38-244) |
Notes:
[1] Data
presented are in annual medians of monthly samples; except those for faecal
coliforms and E. coli which are in
annual geometric means.
[2] Figures in
brackets are annual ranges.
[3] NM
indicates no measurement taken.
[4] cfu - colony forming unit.
[5] Equal
values for annual medians (or geometric means) and ranges indicate that all
data are the same as or below laboratory reporting limits.
[6] Extracted
from EPD River Water Quality in Hong Kong 2014
Table 5.8 Summary of EPD¡¦s routine
marine sediment quality in North Western Water Control Zone at Selected
Stations in 1986 to 2014
Monitoring Stations |
NS2 (Pearl
Island) |
NS3 (Pillar
Point) |
NS4 (Urmston Road) |
NS6 (Chek Lap Kok (North)) |
|||||||||
Max |
Min |
Avg |
Max |
Min |
Avg |
Max |
Min |
Avg |
Max |
Min |
Avg |
||
Zinc |
(mg/kg) |
180 |
38 |
102 |
160 |
39 |
97 |
180 |
57 |
98 |
130 |
32 |
82 |
Vanadium |
(mg/kg) |
50 |
11 |
33 |
64 |
17 |
39 |
73 |
18 |
33 |
71 |
17 |
35 |
Total Volatile Solid |
( % Solid) |
11 |
4 |
7 |
10 |
3 |
7 |
10 |
3 |
6 |
9 |
2 |
6 |
Total Sulphide |
(mg/kg) |
190 |
<0 |
20 |
130 |
<0.1 |
22 |
220 |
<0.1 |
23 |
51 |
0 |
9 |
Total Solid |
(%w/w) |
64 |
35 |
49 |
70 |
38 |
51 |
77 |
34 |
57 |
76 |
37 |
56 |
Total Polychlorinated
Biphenyls |
(£gg/kg) |
18 |
<5 |
14 |
23 |
<5 |
15 |
18 |
<5 |
14 |
18 |
<5 |
14 |
Total Phosphorous |
(mg/kg) |
860 |
84 |
211 |
1200 |
86 |
215 |
1100 |
77 |
198 |
340 |
73 |
164 |
Total Kjeldahl
Nitrogen |
(mg/kg) |
1500 |
120 |
381 |
1200 |
77 |
370 |
810 |
23 |
335 |
860 |
74 |
301 |
Total Cyanide |
(mg/kg) |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
Total Carbon |
(%w/w) |
1 |
0 |
1 |
2 |
0 |
1 |
1 |
0 |
1 |
1 |
0 |
1 |
Silver |
(mg/kg) |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
Pyrene |
(£gg/kg) |
26 |
<5 |
11 |
110 |
<5 |
16 |
34 |
<5 |
12 |
31 |
<5 |
7 |
Phenanthrene |
(£gg/kg) |
180 |
<5 |
11 |
280 |
<5 |
15 |
130 |
<5 |
11 |
37 |
<5 |
7 |
Particle Size Fraction
<63 micrometer |
(%w/w) |
99 |
18 |
71 |
98 |
5 |
67 |
97 |
12 |
50 |
98 |
10 |
62 |
Nickel |
(mg/kg) |
30 |
6 |
20 |
35 |
7 |
20 |
40 |
7 |
18 |
32 |
8 |
19 |
Mercury |
(mg/kg) |
0 |
<0.05 |
0 |
1 |
<0.03 |
0 |
0 |
<0.05 |
0 |
0 |
<0.05 |
0 |
Manganese |
(mg/kg) |
790 |
250 |
479 |
900 |
230 |
535 |
1200 |
440 |
639 |
720 |
200 |
478 |
Lead |
(mg/kg) |
84 |
20 |
42 |
71 |
20 |
40 |
82 |
29 |
42 |
55 |
16 |
34 |
Iron |
(mg/kg) |
39000 |
14000 |
29966 |
47000 |
14000 |
32102 |
62000 |
5500 |
36775 |
57000 |
14000 |
32769 |
Indeno(1,2,3-cd)pyrene |
(£gg/kg) |
15 |
<5 |
7 |
50 |
<5 |
9 |
24 |
<5 |
7 |
8 |
<3 |
5 |
Fluorene |
(£gg/kg) |
12 |
<10 |
10 |
20 |
<10 |
10 |
13 |
<10 |
10 |
10 |
<10 |
10 |
Fluoranthene |
(£gg/kg) |
24 |
<5 |
10 |
130 |
<5 |
15 |
30 |
<5 |
11 |
18 |
<5 |
6 |
Electrochemical Potential
(mV) |
|
-32 |
-380 |
-159 |
-4 |
-432 |
-160 |
-6 |
-428 |
-181 |
-12 |
-380 |
-150 |
Dry Wet Ratio |
|
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
1 |
Dibenzo(ah)anthracene |
(£gg/kg) |
5 |
<5 |
5 |
5 |
<5 |
5 |
5 |
<5 |
5 |
5 |
<5 |
5 |
Copper |
(mg/kg) |
95 |
7 |
42 |
84 |
8 |
35 |
67 |
5 |
28 |
84 |
7 |
21 |
Chrysene |
(£gg/kg) |
18 |
<5 |
7 |
67 |
<5 |
9 |
18 |
<5 |
7 |
13 |
<5 |
5 |
Chromium |
(mg/kg) |
57 |
12 |
35 |
61 |
8 |
34 |
68 |
9 |
31 |
61 |
15 |
31 |
Chemical Oxygen Demand |
(mg/kg) |
20000 |
5900 |
13464 |
23000 |
140 |
14204 |
19000 |
5600 |
13288 |
20000 |
7400 |
12935 |
Cadmium |
(mg/kg) |
11 |
<0.1 |
0 |
10 |
<0.1 |
0 |
9 |
<0.1 |
0 |
13 |
<0.1 |
0 |
Boron |
(mg/kg) |
56 |
9 |
23 |
49 |
1 |
22 |
74 |
1 |
23 |
66 |
7 |
21 |
Benzo(k)fluoranthene |
(£gg/kg) |
9 |
1 |
4 |
38 |
1 |
6 |
14 |
<1 |
4 |
6 |
<1 |
2 |
Benzo(ghi)perylene |
(£gg/kg) |
19 |
3 |
8 |
59 |
3 |
11 |
23 |
1 |
7 |
11 |
<1 |
3 |
Benzo(b)fluoranthene |
(£gg/kg) |
22 |
2 |
8 |
77 |
2 |
11 |
30 |
<1 |
8 |
12 |
<1 |
4 |
Benzo(a)pyrene |
(£gg/kg) |
17 |
1 |
7 |
85 |
<1 |
10 |
17 |
<1 |
6 |
8 |
<1 |
2 |
Benzo(a)anthracene |
(£gg/kg) |
14 |
<3 |
6 |
73 |
<3 |
8 |
12 |
<3 |
5 |
10 |
<3 |
4 |
Barium |
(mg/kg) |
49 |
9 |
31 |
55 |
17 |
32 |
64 |
18 |
30 |
56 |
15 |
28 |
Arsenic |
(mg/kg) |
20 |
2 |
10 |
25 |
2 |
12 |
26 |
4 |
12 |
24 |
6 |
12 |
Anthracene |
(£gg/kg) |
5 |
<5 |
5 |
15 |
<5 |
5 |
5 |
<5 |
5 |
5 |
<5 |
5 |
Ammonia
Nitrogen |
(mg/kg) |
26 |
0 |
5 |
23 |
<0.05 |
7 |
39 |
0 |
9 |
17 |
<0.05 |
4 |
Aluminium |
(mg/kg) |
42000 |
7600 |
25884 |
46000 |
12000 |
26830 |
52000 |
12000 |
22745 |
51000 |
9600 |
24204 |
Acenaphthylene |
(£gg/kg) |
250 |
<50 |
65 |
250 |
<50 |
65 |
250 |
<50 |
65 |
250 |
<50 |
65 |
Acenaphthene |
(£gg/kg) |
100 |
<50 |
54 |
100 |
<50 |
54 |
100 |
<50 |
54 |
100 |
<50 |
54 |
Notes:
[1] NS2 monitoring data
before 1987 is not available.
[2] Both NS3 and NS4
monitoring data started from 1986.
[3] NS6 monitoring data
before 1991 is not available.
[4] Extracted from EPD website
for Marine Water Quality
Table 5.9 Summary of EPD¡¦s routine
marine sediment quality in Western Buffer Water Control Zone at Selected
Stations in 1986 to 2014
Monitoring Stations |
WS1 (Tsing Yi (South)) |
WS2 (Hong
Kong Island (West)) |
|||||
Max |
Min |
Avg |
Max |
Min |
Avg |
||
Zinc |
(mg/kg) |
190 |
9 |
111 |
170 |
66 |
106 |
Vanadium |
(mg/kg) |
51 |
15 |
33 |
50 |
28 |
37 |
Total Volatile Solid |
( % Solid) |
71 |
1 |
8 |
10 |
4 |
7 |
Total Sulphide |
(mg/kg) |
220 |
0 |
64 |
200 |
0 |
27 |
Total Solid |
(%w/w) |
79 |
35 |
47 |
54 |
36 |
44 |
Total Polychlorinated Biphenyls |
(£gg/kg) |
25 |
<5 |
16 |
24 |
5 |
15 |
Total Phosphorous |
(mg/kg) |
450 |
48 |
201 |
1100 |
140 |
225 |
Total Kjeldahl
Nitrogen |
(mg/kg) |
1100 |
9 |
456 |
1800 |
260 |
475 |
Total Cyanide |
(mg/kg) |
0 |
0 |
0 |
0 |
0 |
0 |
Total Carbon |
(%w/w) |
3 |
0 |
1 |
2 |
0 |
1 |
Silver |
(mg/kg) |
3 |
0 |
1 |
3 |
0 |
1 |
Pyrene |
(£gg/kg) |
110 |
<5 |
24 |
43 |
<5 |
12 |
Phenanthrene |
(£gg/kg) |
39 |
<5 |
11 |
39 |
<5 |
8 |
Particle Size Fraction <63 micrometer |
(%w/w) |
98 |
27 |
78 |
99 |
66 |
87 |
Nickel |
(mg/kg) |
47 |
8 |
22 |
31 |
13 |
23 |
Mercury |
(mg/kg) |
2 |
<0.05 |
0 |
1 |
<0.05 |
0 |
Manganese |
(mg/kg) |
890 |
33 |
524 |
760 |
440 |
593 |
Lead |
(mg/kg) |
68 |
<5 |
40 |
54 |
22 |
40 |
Iron |
(mg/kg) |
40000 |
3400 |
30214 |
39000 |
22000 |
32310 |
Indeno(1,2,3-cd)pyrene |
(£gg/kg) |
55 |
<5 |
16 |
22 |
<5 |
8 |
Fluorene |
(£gg/kg) |
15 |
<10 |
10 |
11 |
<10 |
10 |
Fluoranthene |
(£gg/kg) |
90 |
<5 |
24 |
35 |
<5 |
12 |
Electrochemical Potential (mV) |
|
42 |
-603 |
-175 |
58 |
-762 |
-146 |
Dry Wet Ratio |
|
1 |
0 |
0 |
1 |
0 |
0 |
Dibenzo(ah)anthracene |
(£gg/kg) |
12 |
<5 |
5 |
6 |
<5 |
5 |
Copper |
(mg/kg) |
280 |
<1 |
62 |
140 |
17 |
39 |
Chrysene |
(£gg/kg) |
48 |
<5 |
12 |
17 |
<5 |
7 |
Chromium |
(mg/kg) |
84 |
13 |
40 |
59 |
23 |
38 |
Chemical Oxygen Demand |
(mg/kg) |
21000 |
190 |
14758 |
21000 |
3900 |
13795 |
Cadmium |
(mg/kg) |
9 |
<0.1 |
0 |
9 |
<0 |
0 |
Boron |
(mg/kg) |
47 |
<1 |
26 |
49 |
11 |
29 |
Benzo(k)fluoranthene |
(£gg/kg) |
33 |
2 |
10 |
14 |
2 |
5 |
Benzo(ghi)perylene |
(£gg/kg) |
55 |
2 |
18 |
23 |
2 |
10 |
Benzo(b)fluoranthene |
(£gg/kg) |
63 |
2 |
19 |
25 |
1 |
10 |
Benzo(a)pyrene |
(£gg/kg) |
74 |
2 |
19 |
26 |
2 |
9 |
Benzo(a)anthracene |
(£gg/kg) |
55 |
<3 |
13 |
21 |
<3 |
6 |
Barium |
(mg/kg) |
58 |
15 |
35 |
56 |
25 |
38 |
Arsenic |
(mg/kg) |
14 |
2 |
9 |
17 |
1 |
9 |
Anthracene |
(£gg/kg) |
5 |
<5 |
5 |
5 |
<5 |
5 |
Ammonia Nitrogen |
(mg/kg) |
38 |
0 |
10 |
35 |
<0.05 |
6 |
Aluminium |
(mg/kg) |
45000 |
1400 |
27100 |
45000 |
18000 |
30309 |
Acenaphthylene |
(£gg/kg) |
250 |
<50 |
65 |
250 |
<50 |
65 |
Acenaphthene |
(£gg/kg) |
100 |
<50 |
54 |
100 |
<50 |
54 |
Note:
[1] Both WS1 and WS2
monitoring data started from 1988.
Table 5.10 Summary of EPD¡¦s routine beach water quality in Tuen Mun from 1997 to 2014
E. coli counts per 100ml (annual geometric mean) |
||||||||||||||||||
Beach |
1997 |
1998 |
1999 |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
2007 |
2008 |
2009 |
2010 |
2011 |
2012 |
2013 |
2014 |
Butterfly |
259 |
121 |
44 |
61 |
74 |
60 |
74 |
55 |
55 |
94 |
84 |
56 |
49 |
30 |
41 |
42 |
71 |
38 |
Cafeteria New |
309 |
100 |
60 |
51 |
104 |
62 |
80 |
54 |
70 |
120 |
68 |
48 |
38 |
31 |
27 |
47 |
50 |
31 |
Cafeteria Old |
435 |
138 |
58 |
57 |
125 |
74 |
76 |
61 |
81 |
150 |
67 |
45 |
46 |
34 |
29 |
48 |
39 |
45 |
Castle Peak |
332* |
199* |
57* |
58* |
105* |
58* |
64* |
80* |
90 |
139 |
64 |
47 |
35 |
63 |
49 |
48 |
78 |
91 |
Golden |
352 |
98 |
44 |
50 |
87 |
66 |
84 |
46 |
62 |
117 |
87 |
63 |
42 |
37 |
26 |
62 |
45 |
39 |
Kadoorie |
290 |
130 |
109 |
68 |
120 |
114 |
160 |
98 |
117 |
118 |
101 |
87 |
48 |
45 |
37 |
40 |
52 |
37 |
Source:
EPD Beach
Water Quality in Hong Kong 2014
Note:
*The beach was closed in the selected years
Table 5.11 Summary of EPD¡¦s routine beach water quality
in Tsuen Wan from 1997 to 2014
E. coli counts per 100ml (annual geometric mean) |
||||||||||||||||||
Beach |
1997 |
1998 |
1999 |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
2007 |
2008 |
2009 |
2010 |
2011 |
2012 |
2013 |
2014 |
Anglers¡¦ |
691* |
502* |
442* |
326* |
621* |
1169* |
693* |
619* |
895* |
772* |
496* |
510* |
276* |
134* |
27* |
69* |
133 |
130 |
Approach |
1009* |
435* |
387* |
316* |
411* |
696* |
762* |
470* |
663* |
599* |
352* |
251* |
208* |
124* |
59 |
83 |
106 |
121 |
Casam |
609 |
239 |
231 |
209 |
233 |
741 |
702* |
594* |
716* |
426* |
305* |
289* |
144* |
102* |
21 |
50 |
71 |
63 |
Gemini |
458 |
399 |
350 |
258 |
323 |
1155 |
875* |
1102* |
1042* |
853* |
566* |
481* |
410* |
137* |
19* |
40* |
135* |
110* |
Hoi Mei Wan |
471 |
280 |
109 |
177 |
199 |
547 |
442* |
287* |
641* |
308* |
286* |
271* |
130* |
87* |
23 |
51 |
86 |
58 |
Lido |
600 |
262 |
231 |
181 |
269 |
683 |
734* |
523* |
782* |
459* |
280* |
296* |
178* |
87* |
21 |
32 |
53 |
57 |
Ma Wan Tung Wan |
110 |
92 |
51 |
39 |
133 |
201 |
159 |
101 |
132 |
171 |
78 |
53 |
60 |
17 |
10 |
24 |
41 |
31 |
Source:
EPD Beach
Water Quality in Hong Kong 2014
Note:
*The beach
was closed in the selected years
Table 5.12 Pore water results from present study
Sampling Location |
Metals (£gg/L) |
Metalloid (£gg/L) |
TKN (mg/L) |
NH3-N (mg/L) |
NO3-N (mg/L) |
NO2-N (mg/L) |
TIN [1] (mg/L) |
UIA [2] (mg/L) |
Total P (mg/L) |
Ortho-P (mg/L) |
|||||||
Ni |
Hg |
Cd |
Ag |
Cr |
Cu |
Pb |
Zn |
As |
|||||||||
Criteria / Baseline |
8.2 |
0.05 |
3.1 |
1.9 |
15 |
5 |
0.5 |
0.021 |
25 |
- |
- |
- |
- |
0.5 |
0.021 |
- |
- |
VB1 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
2.0 |
0.08 |
<10 |
2 |
1.95 |
<0.01 |
<0.01 |
1.97 |
0.08 |
0.1 |
0.07 |
VB2 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
3.1 |
0.12 |
<10 |
3.4 |
3.03 |
<0.01 |
<0.01 |
3.05 |
0.12 |
0.2 |
0.22 |
VB3 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
2.8 |
0.11 |
<10 |
3 |
2.77 |
<0.01 |
<0.01 |
2.79 |
0.11 |
0.4 |
0.47 |
VB4 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
4.0 |
0.16 |
<10 |
4.1 |
4 |
<0.01 |
<0.01 |
4.02 |
0.16 |
0.4 |
0.33 |
VB5 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
12.8 |
0.50 |
28 |
12.8 |
12.8 |
<0.01 |
<0.01 |
12.82 |
0.50 |
1.9 |
1.7 |
VB6 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
2.5 |
0.10 |
<10 |
3.1 |
2.48 |
<0.01 |
<0.01 |
2.50 |
0.10 |
0.2 |
0.14 |
VB7 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.3 |
0.05 |
<10 |
2.5 |
1.32 |
<0.01 |
<0.01 |
1.34 |
0.05 |
0.5 |
0.02 |
VB8 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.2 |
0.04 |
<10 |
1.8 |
1.12 |
0.03 |
<0.01 |
1.16 |
0.04 |
0.1 |
0.06 |
VB9 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
4.1 |
0.16 |
<10 |
4.1 |
4.07 |
<0.01 |
<0.01 |
4.09 |
0.16 |
0.2 |
0.3 |
VB10 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
5.2 |
0.20 |
<10 |
10.2 |
5.18 |
<0.01 |
0.02 |
5.21 |
0.20 |
1.2 |
0.03 |
VB11 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.1 |
0.04 |
<10 |
1.8 |
1.12 |
<0.01 |
<0.01 |
1.14 |
0.04 |
0.2 |
0.07 |
VB12 |
<1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.1 |
0.04 |
<10 |
1.5 |
1.09 |
<0.01 |
<0.01 |
1.11 |
0.04 |
0.1 |
0.09 |
VB13 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
0.9 |
0.04 |
<10 |
1.4 |
0.9 |
0.02 |
<0.01 |
0.93 |
0.04 |
0.1 |
0.04 |
VB14 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.3 |
0.05 |
<10 |
1.8 |
1.3 |
0.02 |
0.02 |
1.34 |
0.05 |
0.2 |
0.07 |
VB15 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
0.8 |
0.03 |
<10 |
2.1 |
0.74 |
<0.01 |
<0.01 |
0.76 |
0.03 |
0.2 |
0.01 |
VB16 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
1 |
1.1 |
0.04 |
<10 |
2.1 |
1.04 |
<0.01 |
<0.01 |
1.06 |
0.04 |
0.2 |
0.02 |
VB17 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
4.4 |
0.17 |
<10 |
5.6 |
4.37 |
<0.01 |
<0.01 |
4.39 |
0.17 |
0.2 |
0.22 |
VB18 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
3.6 |
0.14 |
<10 |
3.6 |
3.55 |
<0.01 |
<0.01 |
3.57 |
0.14 |
0.1 |
0.08 |
VB19 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
6.4 |
0.25 |
<10 |
7 |
6.35 |
<0.01 |
<0.01 |
6.37 |
0.25 |
0.2 |
0.09 |
VB20 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
2 |
1.1 |
0.04 |
<10 |
1.9 |
1.09 |
<0.01 |
<0.01 |
1.11 |
0.04 |
0.2 |
0.02 |
VB21 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.0 |
0.04 |
<10 |
2 |
0.99 |
<0.01 |
0.01 |
1.01 |
0.04 |
0.2 |
0.06 |
VB22 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.0 |
0.04 |
<10 |
1.9 |
0.99 |
<0.01 |
<0.01 |
1.01 |
0.04 |
0.1 |
0.01 |
VB23 |
1 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.4 |
0.06 |
<10 |
2.3 |
1.4 |
<0.01 |
<0.01 |
1.42 |
0.06 |
0.2 |
0.02 |
VB24 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
0.9 |
0.03 |
<10 |
0.9 |
0.84 |
<0.01 |
<0.01 |
0.86 |
0.03 |
<0.1 |
0.03 |
VB25 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.0 |
0.04 |
<10 |
3 |
0.95 |
<0.01 |
<0.01 |
0.97 |
0.04 |
0.2 |
0.01 |
VB26 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
0.9 |
0.04 |
<10 |
1.2 |
0.91 |
<0.01 |
<0.01 |
0.93 |
0.04 |
0.1 |
0.04 |
VB27 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.2 |
0.05 |
<10 |
1.9 |
1.16 |
0.02 |
<0.01 |
1.19 |
0.05 |
0.1 |
0.06 |
VB28 |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
<1 |
1.4 |
0.05 |
<10 |
1.8 |
1.28 |
0.06 |
0.02 |
1.36 |
0.05 |
0.1 |
0.05 |
Maximum |
2 |
<0.05 |
<0.2 |
<1 |
<1 |
2 |
12.8 |
0.50 |
28 |
12.8 |
12.8 |
0.06 |
0.02 |
12.82 |
0.50 |
1.9 |
1.7 |
Notes:
[1] TIN
is calculated by summation of NO2-N, NO3-N and NH3-N
[2] UIA
is estimated by multiplying a percentage factor to NH3-N. This
factor depends on temp and pH. The average temp and
pH from EPD water quality monitoring stations in North Western WCZ are 23.6 degC and 7.9 respectively. According to the ¡§Aqueous
Ammonia Equilibrium- Tabulation of Percent Unionized Ammonia¡¨ from USEPA, the
conversion factor is 3.93%.
Table
5.13: Summary of water
quality parameters recorded from November 2002 to January 2011 for HKIA
Averaging Period |
Area |
Surface Temp. |
Mid-Depth Temp. |
Surface Salinity |
DO |
Turbidity |
SS |
BOD5 |
TKN |
TIN |
TRC |
Unit |
|
ºC |
ºC |
ppt |
mg/L |
NTU |
mg/L |
mg/L |
mg/L |
mg/L |
mg/L |
WQO |
|
<¡Ó2ºC |
<¡Ó2ºC |
<¡Ó10% |
> 4 mg/L |
- |
<+30% |
- |
- |
< 0.5 mg/L |
- |
Nov 2002 |
Impact |
23.6 |
23.5 |
31.4 |
6.2 |
339.3 |
10.4 |
<2 |
0.4 |
N/A |
N/A |
Control |
23.6 |
23.5 |
31.4 |
6.2 |
390.3 |
23.0 |
<2 |
0.6 |
N/A |
N/A |
|
Jan 2003 |
Impact |
17.8 |
17.8 |
28.9 |
9.2 |
7.3 |
13.4 |
2.0 |
0.5 |
N/A |
N/A |
Control |
17.6 |
17.5 |
28.8 |
9.5 |
5.3 |
12.5 |
2.0 |
0.5 |
N/A |
N/A |
|
Mar 2003 |
Impact |
21.2 |
21.0 |
31.8 |
7.0 |
12.4 |
13.6 |
<2 |
0.6 |
N/A |
N/A |
Control |
20.9 |
20.1 |
31.0 |
7.0 |
12.0 |
15.5 |
<2 |
0.6 |
N/A |
N/A |
|
May 2003 |
Impact |
26.3 |
26.0 |
24.8 |
8.5 |
8.0 |
6.2 |
<2 |
0.1 |
N/A |
N/A |
Control |
26.5 |
25.8 |
25.7 |
6.7 |
-16.6 |
10.5 |
<2 |
0.2 |
N/A |
N/A |
|
Jun 2003 |
Impact |
27.4 |
27.3 |
14.9 |
5.3 |
15.7 |
14.2 |
<2 |
0.1 |
N/A |
N/A |
Control |
27.5 |
27.4 |
13.2 |
5.4 |
20.0 |
13.0 |
<2 |
0.2 |
N/A |
N/A |
|
Jul 2003 |
Impact |
30.5 |
30.3 |
16.0 |
6.0 |
24.3 |
10.4 |
<2 |
0.1 |
N/A |
N/A |
Control |
29.6 |
29.0 |
16.5 |
4.6 |
47.7 |
13.0 |
<2 |
0.2 |
N/A |
N/A |
|
Aug 2003 |
Impact |
30.3 |
30.1 |
20.7 |
5.8 |
21.1 |
19.8 |
<2 |
0.1 |
N/A |
N/A |
Control |
30.4 |
29.4 |
18.7 |
4.9 |
17.5 |
11.0 |
<2 |
0.1 |
N/A |
N/A |
|
Oct 2003 |
Impact |
26.4 |
26.4 |
32.0 |
9.5 |
9.8 |
5.8 |
<2 |
0.2 |
N/A |
N/A |
Control |
26.2 |
26.1 |
32.0 |
8.2 |
12.4 |
9.5 |
<2 |
0.4 |
N/A |
N/A |
|
Dec 2005 |
Impact |
17.9 |
17.8 |
32.7 |
8.1 |
5.0 |
5.8 |
<2 |
0.8 |
0.1 |
<0.2 |
Control |
17.9 |
17.3 |
32.7 |
8.7 |
7.8 |
8.0 |
<2 |
0.8 |
0.1 |
<0.2 |
|
Feb 2006 |
Impact |
17.7 |
17.8 |
30.2 |
7.1 |
6.7 |
7.2 |
<2 |
0.3 |
0.3 |
<0.2 |
Control |
17.8 |
17.8 |
30.6 |
7.1 |
6.8 |
7.0 |
<2 |
0.3 |
0.3 |
<0.2 |
|
Apr 2006 |
Impact |
22.4 |
22.2 |
26.5 |
6.6 |
8.0 |
8.0 |
<2 |
0.4 |
0.8 |
<0.2 |
Control |
21.9 |
21.5 |
28.0 |
6.4 |
7.1 |
12.5 |
<2 |
0.4 |
0.5 |
<0.2 |
|
Jun 2006 |
Impact |
26.2 |
26.3 |
8.8 |
7.0 |
6.2 |
3.6 |
<2 |
0.3 |
1.5 |
<0.2 |
Control |
26.3 |
26.3 |
8.6 |
6.5 |
5.3 |
4.0 |
<2 |
0.3 |
1.5 |
<0.2 |
|
Aug 2006 |
Impact |
29.8 |
29.8 |
11.6 |
6.5 |
7.2 |
6.0 |
<2 |
0.1 |
1.1 |
<0.2 |
Control |
29.9 |
29.8 |
10.5 |
6.3 |
7.2 |
5.5 |
<2 |
0.3 |
1.2 |
<0.2 |
|
Oct 2006 |
Impact |
28.1 |
28.0 |
28.4 |
5.2 |
8.0 |
9.4 |
<2 |
0.5 |
0.6 |
<0.2 |
Control |
28.0 |
27.6 |
26.9 |
5.0 |
5.5 |
6.0 |
<2 |
0.5 |
0.5 |
<0.2 |
|
Mar 2010 |
Impact |
20.5 |
20.5 |
29.2 |
7.1 |
11.6 |
9.2 |
<2 |
0.2 |
0.6 |
<0.2 |
Control |
19.8 |
20 |
29.1 |
7.4 |
14.2 |
11.5 |
<2 |
0.3 |
0.6 |
<0.2 |
|
May 2010 |
Impact |
26.6 |
26.4 |
18.2 |
5.5 |
7 |
7.2 |
<2 |
0.4 |
1.1 |
<0.2 |
Control |
25.7 |
25.1 |
20.7 |
5.4 |
8.8 |
9 |
<2 |
0.4 |
0.8 |
<0.2 |
|
Jul 2010 |
Impact |
29.2 |
29.1 |
9.7 |
10.8 |
12.2 |
12.8 |
2 |
0.4 |
1.1 |
<0.2 |
Control |
29.1 |
29 |
8.6 |
9.6 |
9.7 |
10 |
2.5 |
0.5 |
1.2 |
<0.2 |
|
Sep 2010 |
Impact |
28.3 |
27.7 |
21.7 |
4.4 |
12.1 |
12.4 |
<2 |
0.3 |
1.1 |
<0.2 |
Control |
27.9 |
26.4 |
21.8 |
3.4 |
17.4 |
18 |
<2 |
0.3 |
0.9 |
<0.2 |
|
Nov 2010 |
Impact |
23.2 |
23 |
30.6 |
6.7 |
14.7 |
15.2 |
<2 |
0.2 |
0.3 |
<0.2 |
Control |
23.3 |
23 |
30.3 |
6.3 |
11.7 |
20 |
<2 |
0.3 |
0.3 |
<0.2 |
|
Jan 2011 |
Impact |
16.8 |
16.8 |
32.6 |
8.6 |
18.6 |
25.4 |
<2 |
0.2 |
0.2 |
<0.2 |
Control |
17.1 |
17.1 |
32.6 |
8.1 |
29.8 |
19 |
<2 |
0.2 |
0.2 |
<0.2 |
|
Average |
Impact |
24.5 |
24.4 |
24.0 |
7.1 |
27.8 |
10.8 |
<2 |
0.3 |
0.7 |
<0.2 |
|
Control |
24.3 |
24.0 |
23.9 |
6.6 |
31.0 |
11.9 |
<2 |
0.4 |
0.7 |
<0.2 |
Source:
Approved EIA (EIA 223/2014) for Expansion of Hong Kong Airport into a
Three-Runway System
Note:
¡± All data
are mid-depth average value unless stated otherwise.
¡± Shaded cell
represents the value exceeded the relevant WQOs.
Table 5.14 Routine water quality monitoring results from Aug 2006 to May 2013 for new CMPs at East of Sha Chau
SS |
Turbidity |
DO |
Cr |
Cu |
Pb |
Zn |
|
(mg/L) |
(NTU) |
(mg/L) |
(£gg/L) |
(£gg/L) |
(£gg/L) |
(£gg/L) |
|
Reference
Station |
11.21 |
7.33 |
6.7 |
0.63 |
4.55 |
1.15 |
8.93 |
Mid-field |
11.45 |
7.26 |
6.65 |
0.62 |
4.21 |
1.27 |
7.32 |
Impact
Station |
11.39 |
6.93 |
6.63 |
0.6 |
5.07 |
1.08 |
8.78 |
Source: CEDD
Routine Water Quality Monitoring at Airport East / East Sha
Chau
Table 5.15 Water quality
monitoring results from Aug 2006 to May 2013 for new CMPs at East of Sha Chau
Parameter |
Near Field Stations |
Results (average) |
Salinity (ppt) |
DS1(Down Stream Station) |
24.68 |
DS2(Down Stream Station) |
24.5 |
|
DS3(Down Stream Station) |
24.62 |
|
DS4(Down Stream Station) |
24.59 |
|
DS5(Down Stream Station) |
24.28 |
|
MW1(Ma Wan Station) |
27.69 |
|
US1(Upstream Station) |
24.69 |
|
US2(Upstream Station) |
24.94 |
|
Dissolved Oxygen (mg/L) |
DS1(Down Stream Station) |
7.13 |
DS2(Down Stream Station) |
7.15 |
|
DS3(Down Stream Station) |
7.07 |
|
DS4(Down Stream Station) |
7.07 |
|
DS5(Down Stream Station) |
7.11 |
|
MW1(Ma Wan Station) |
6.72 |
|
US1(Upstream Station) |
7.17 |
|
US2(Upstream Station) |
7.14 |
|
Turbidity (NTU) |
DS1(Down Stream Station) |
12.95 |
DS2(Down Stream Station) |
11.14 |
|
DS3(Down Stream Station) |
10.81 |
|
DS4(Down Stream Station) |
9.54 |
|
DS5(Down Stream Station) |
8.95 |
|
MW1(Ma Wan Station) |
5.86 |
|
US1(Upstream Station) |
10.94 |
|
US2(Upstream Station) |
11.04 |
|
pH |
DS1(Down Stream Station) |
7.8 |
DS2(Down Stream Station) |
7.8 |
|
DS3(Down Stream Station) |
7.79 |
|
DS4(Down Stream Station) |
7.79 |
|
DS5(Down Stream Station) |
7.78 |
|
MW1(Ma Wan Station) |
7.77 |
|
US1(Upstream Station) |
7.79 |
|
US2(Upstream Station) |
7.79 |
|
Suspended Solids (mg/L) |
DS1(Down Stream Station) |
17.41 |
DS2(Down Stream Station) |
14.45 |
|
DS3(Down Stream Station) |
14.11 |
|
DS4(Down Stream Station) |
12.42 |
|
DS5(Down Stream Station) |
11.37 |
|
MW1(Ma Wan) |
8.52 |
|
US1(Upstream Station) |
14.5 |
|
US2(Upstream Station) |
14.35 |
Source:
ERM (2009). Environmental Monitoring and Audit for Contaminated Mud Pit at Sha Chau (2009-2013) ¡V EM&A
Impact Results (http://www.cmp-monitoring.com.hk/EM&A%20Data.html).
5.3
Indication
Point and Methodology of Quantitative Modelling
5.3.1
General Description
5.3.1.1
As discussed in Section 2.3, the project has been proactively designed to reduce
both the ecological and water quality impacts by avoiding any reclamation in
TCW. On comparing to the original scheme with 50ha reclamation (see Section 2), the current
scheme with the removal of TCW reclamation, would further improve the ecology
and water quality condition on TCW. However, there would still be a need
for a reclamation of 129.1 ha for TCE and Road P1
(Tung Chung ¡V Tai Ho Section). In order to
minimize the potential impacts caused by the reclamation, a number of
alternative construction methodologies has been
critically examined. After considering all the options such as fully
dredged, partially dredged and non-dredged methods for seawall construction and
reclamation, non-dredged method for both the seawall construction and
reclamation are recommended so as to minimize the generation of dredged
sediment. Nevertheless, the construction work would still require filling
work which would still inevitably generate suspended solids. Besides, the
filling process would also generate pore water from the sediment. Hence,
a quantitative water quality modelling would be required to assess the impacts
during the seawall construction and the reclamation process.
5.3.1.2
During the operational phase, the proposed TCE
reclamation would have potential impacts on the hydrodynamic conditions and the
water quality. This would need to be quantitatively assessed. It is
noted that all the sewage generated from the additional population and
employment would be conveyed to Siu Ho Wan Sewage Treatment Works for treatment before discharge.
However, the surface run-off would still be discharged into the
neighbouring water. The water quality model would therefore need to
evaluate the impacts from surface runoff.
5.3.1.3
Irrespective of the construction and
operational impacts, the cumulative impacts caused by concurrent projects would
need to be considered. The potential concurrent projects include 3RS, HZMB-HKBCF,
HZMB-HKLR, TM-CLKL, etc, which are discussed in the
following sections.
5.3.2
Selection of Representative Water Sensitive
Receivers
5.3.2.1
Indicator points were selected in the water
quality model to provide hydrodynamic and water quality outputs to evaluate
water quality impact. The selected indicator points include water quality
sensitive receivers (WSRs) and EPD marine water sampling stations.
5.3.2.2
The WSRs in the vicinity of the project area
including ecological sensitive area with conservation importance, commercial
fishing resources, areas of direct human contact, e.g. bathing beaches, and
seawater extraction points are shown in Table
5.16a.
5.3.2.3
In addition to the WSRs, a number of locations
of interest within the study area are included as observation points in the
assessment as shown in Table 5.16b.
Table 5.16a Summary of the Representative Water
Sensitive Receivers
ID |
Description |
Impact |
WSR 01 |
Yat Tung East Channel |
Construction and Operation |
WSR 02 |
Yat Tung West Channel |
Construction and Operation |
WSR 03 |
Estuary of
Tung Chung Stream |
Construction and Operation |
WSR 04 |
Marine
Park at Brothers Islands and Tai Mo To (Dolphin Habitat) |
Construction and Operation |
WSR 05a-b |
River
Trade Terminal |
Construction and Operation |
WSR 06 |
Coral
Communities at The Brothers Islands |
Construction and Operation |
WSR 07 |
Black
Point Power Station Cooling Water Intake |
Construction and Operation |
WSR 08 |
Lung Kwu Sheung Tan (non-gazetted
beach) |
Construction |
WSR 10 |
Sha Chau and Lung Kwu
Chau Marine Park |
Construction and Operation |
WSR 11 |
Castle
Peak Power Station Cooling Water Intake |
Construction and Operation |
WSR 12 |
Butterfly
Beach |
Construction and Operation |
WSR 13 |
WSD Tuen Mun Salt Water Pumping
Station with Salt Water Intake |
Construction and Operation |
WSR 14 |
Tuen Mun Typhoon
Shelter |
Construction and Operation |
WSR 15 |
Gazetted
Beaches at Tuen Mun |
Construction and Operation |
WSR 16 |
Gold Coast
Marina |
Construction and Operation |
WSR 17 |
WSD Lok On Pai Salt Water Pumping
Station with Salt Water Intake |
Construction and Operation |
WSR 18 |
Gazetted
beaches along Castle Peak Road |
Construction and Operation |
WSR 19 |
Gazetted
beaches at Ma Wan |
Construction and Operation |
WSR 20 |
Ma Wan
Fish Culture Zone |
Construction and Operation |
WSR 21 |
WSD Sunny
Bay Salt Water Pumping Station with Salt Water Intake |
Construction and Operation |
WSR 22a |
Tai Ho Wan Inlet (inside) |
Construction and Operation |
WSR 22b |
Tai Ho Bay (inner), Near Tai Ho
Stream SSSI |
Construction and Operation |
WSR 22c |
Tai Ho Wan Inlet (outside) |
Construction and Operation |
WSR 23 |
Future
Seawater Intake for LLP (Flushing) |
Operation |
WSR 25 |
Cooling
water intake at Hong Kong International Airport (North) |
Construction and Operation |
WSR 26 |
Future
Cooling Seawater Intake at Hong Kong International Airport (East) |
Construction and Operation |
WSR 27 |
San Tau
Beach SSSI |
Construction and Operation |
WSR 28 |
Cooling
Water Intake at Hong Kong International Airport (South) |
Construction and Operation |
WSR 29 |
Hau Hok Wan (Horseshoe Crab Habitat) |
Construction and Operation |
WSR 30 |
Sha Lo Wan (Horseshoe Crab Habitat) |
Construction and Operation |
WSR 31 |
Sham Wat Wan (Mangrove and Horseshoe Crab Habitat) |
Construction and Operation |
WSR 32 |
Tai O
(Mangrove Habitat) |
Construction and Operation |
WSR 33 |
Tai O Bay |
Construction and Operation |
WSR 34 |
Yi O
(Mangrove and Horseshoe Crab Habitat) |
Construction and Operation |
WSR 35 |
Potential
marine park / marine reserve for SW Lantau |
Operation |
WSR 41 |
Artificial
Reef at Northeast Airport |
Construction and Operation |
WSR 42 |
Artificial
Reef and coral communities at Sha Chau |
Construction and Operation |
WSR 43 |
Proposed
Seawater intake for Tung Chung (Flushing) |
Operation |
WSR 44 |
Future
HKBCF Intake (Flushing) |
Construction and Operation |
WSR 45 |
Sham Shui Kok (Dolphin Habitat) |
Construction and Operation |
WSR 46 |
Proposed
Marina at Tung Chung East Reclamation |
Operation |
Table 5.16b Summary of the Observation Points
ID |
Description |
M1-M5 |
Five corners of Brothers Islands Marine Park |
M6-M10 |
Four corners and southern boundary mid-point of Sha
Chau and Lung Kwu Chau Marine Park |
5.3.2.4
Figure 5.1 shows the locations of these WSRs. The locations
of EPD marine water sampling stations at North Western Water Quality Zone (NM1,
NM2, NM3, NM5, NM6, NM8, WM4, TC1, TC2 and TC3) are also shown in the figure
for reference.
5.3.2.5
According to the
latest design, there would be no seawater cooling discharge from Tung Chung New
Town development. In case, there is a need to re-consider the seawater cooling
facilities, a separate study shall be conducted by the operator.
5.3.3
Proposed Suspended Solids
Criteria for Indicator Points
5.3.3.1
According to WQO, the criteria for SS is defined as ¡§waste discharge not to raise
the natural ambient level by 30% nor cause the accumulation of SS which may
adversely affect aquatic communities¡¨. It is expected that the North Western
WCZ will be affected from the construction works. In order to determine the
ambient SS concentrations in the waters likely to be affected by the
construction works, water quality monitoring data from NM1, NM2, NM3, NM5, NM6,
NM8 and WM4 in the WCZ have been analyzed.
5.3.3.2
EPD marine water
quality data in sea surface, mid-depth and the bottom are presented in Table 5.17. The sampling in wet season was
taken from April until the end of September in each year.
Table 5.17 SS
concentrations from EPD Routine Monitoring Programme (2005-2014)
Station |
SS
Concentrations (mg/L) |
|||||||
Surface |
Middle |
Bottom |
Depth
Averaged |
|||||
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
|
NM1 |
6.0 |
4.7 |
8.0 |
6.3 |
9.6 |
11.7 |
7.9 |
7.6 |
(1.4-22) |
(0.9-20) |
(0.8-22) |
(0.8-27) |
(0.9-40) |
(1.2-55) |
(1.4-27) |
(1.1-26) |
|
NM2 |
5.6 |
4.5 |
6.9 |
4.8 |
9.8 |
6.1 |
7.4 |
5.2 |
(1.3-19) |
(1.4-15) |
(1.2-28) |
(1-17) |
(1.5-40) |
(1-24) |
(1.6-26) |
(1.5-15) |
|
NM3 |
6.2 |
5.1 |
8.1 |
6.3 |
11.3 |
9.7 |
8.5 |
7.0 |
(1.3-18) |
(1.2-15) |
(1.4-35) |
(1.3-22) |
(1.5-46) |
(1.5-27) |
(1.8-31) |
(2.1-17) |
|
NM5 |
7.9 |
5.8 |
10.5 |
7.3 |
16.3 |
18.9 |
11.6 |
10.7 |
(1.6-23) |
(1.2-19) |
(1.6-29) |
(2-22) |
(2.6-61) |
(2.4-150) |
(2-33) |
(2.6-54) |
|
NM6 |
10.6 |
7.1 |
11.5 |
11.5 |
14.6 |
6.5 |
12.2 |
8.4 |
(2.2-40) |
(1.6-22) |
(2.5-45) |
(2-36) |
(2.4-52) |
(1.6-84) |
(2.5-44) |
(2.6-34) |
|
NM8 |
11.9 |
5.6 |
14.3 |
7.6 |
20.7 |
15.1 |
15.6 |
9.4 |
(1.7-50) |
(1.3-18) |
(2.6-63) |
(1.3-30) |
(3.8-73) |
(2.2-45) |
(2.7-59) |
(1.9-26) |
|
WM4 |
4.5 |
3.8 |
6.6 |
5.1 |
9.0 |
9.3 |
6.7 |
6.1 |
(0.9-15) |
(0.8-12) |
(0.8-23) |
(1.1-14) |
(2.1-36) |
(2.2-20) |
(1.4-20) |
(2.1-14) |
Note:
The data are
presented as the arithmetic mean and range (max ¡V min) of the SS concentrations
at each station at the three monitoring levels and as the depth averaged
concentrations.
5.3.3.3
The 90 percentiles for each station summarized in Table 5.18.
Table 5.18 90th Percentile SS from EPD Routine Monitoring Programme (2005-2014)
Station |
90th
Percentile Suspended Solids Concentrations (mg/L) |
|||||||
|
Surface |
Middle |
Bottom |
Depth
Averaged |
||||
Dry Season |
Wet Season |
Dry Season |
Wet Season |
Dry Season |
Wet Season |
Dry Season |
Wet Season |
|
NM1 |
11.0 |
6.7 |
16.1 |
11.0 |
17.1 |
19.2 |
14.7 |
12.0 |
NM2 |
9.2 |
8.1 |
10.1 |
8.5 |
18.4 |
9.6 |
13.0 |
8.2 |
NM3 |
11.0 |
8.1 |
13.0 |
10.0 |
21.1 |
17.1 |
14.3 |
11.5 |
NM5 |
14.0 |
9.7 |
19.1 |
13.2 |
32.2 |
36.2 |
20.7 |
20.2 |
NM6 |
21.4 |
8.9 |
25.2 |
11.0 |
32.0 |
23.0 |
26.2 |
14.6 |
NM8 |
23.1 |
10.0 |
26.2 |
16.3 |
42.4 |
31.4 |
30.0 |
18.7 |
WM4 |
8.0 |
5.8 |
11.1 |
9.0 |
17.2 |
17.0 |
12.2 |
9.6 |
5.3.3.4
The SS criteria were derived from 30% of the
90th Percentile SS concentration measurement at the corresponding EPD¡¦s
Monitoring Stations (Table 5.18) and
are summarized in Table 5.19. The SS
criteria are the allowable elevation of SS.
Table 5.19 Suspended solids criteria (mg/L)
for the construction phase impacts
Station |
Suspended
Solids Criteria (mg/L) |
|||||||
Surface |
Middle |
Bottom |
Depth
Averaged |
|||||
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
Dry
Season |
Wet
Season |
|
NM1 |
3.3 |
2.0 |
4.8 |
3.3 |
5.1 |
5.8 |
4.4 |
3.6 |
NM2 |
2.8 |
2.4 |
3.0 |
2.6 |
5.5 |
2.9 |
3.9 |
2.5 |
NM3 |
3.3 |
2.4 |
3.9 |
3.0 |
6.3 |
5.1 |
4.3 |
3.5 |
NM5 |
4.2 |
2.9 |
5.7 |
4.0 |
9.7 |
10.9 |
6.2 |
6.1 |
NM6 |
6.4 |
2.7 |
7.6 |
3.3 |
9.6 |
6.9 |
7.9 |
4.4 |
NM8 |
6.9 |
3.0 |
7.9 |
4.9 |
12.7 |
9.4 |
9.0 |
5.6 |
WM4 |
2.4 |
1.7 |
3.3 |
2.7 |
5.2 |
5.1 |
3.7 |
2.9 |
5.3.3.5
The corresponding SS criterion for each WSR is
presented in Table 5.20.
Table 5.20 Suspended solids criteria (mg/L)
for the construction phase impacts at the water sensitive receivers
WSR |
Corresponding EPD¡¦s
Stations |
Cooling/
Flushing Seawater Intake |
Suspended
Solids Criteria (mg/L) |
|||||||
Dry
Season |
Wet
Season |
|||||||||
S |
M |
B |
DA |
S |
M |
B |
DA |
|||
WSR 01 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 02 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 03 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 04 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 05a-b |
NM3 |
- |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
WSR 06 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 07 [1] |
- |
Cooling |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
WSR 08 |
NM5 |
- |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
WSR 10 |
NM5 |
- |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
WSR 11 [1] |
- |
Cooling |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
WSR 12 |
NM3 |
- |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
WSR 13 [2] |
- |
Flushing |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
WSR 14 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 15 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 16 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 17 [2] |
- |
Flushing |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
WSR 18 |
NM1 |
- |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
WSR 19 |
WM4 |
- |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
WSR 20 |
WM4 |
- |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
WSR 21 [2] |
- |
Flushing |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
WSR 22a |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 22b |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 22c |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 23 [2] |
- |
Flushing |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
WSR 25 |
NM3 |
Cooling |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
WSR 26 |
NM3 |
Cooling |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
WSR 27 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 28 |
NM8 |
Cooling |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 29 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 30 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 31 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 32 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 33 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 34 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 35 |
NM8 |
- |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
WSR 41 |
NM5 |
- |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
WSR 42 |
NM5 |
- |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
WSR 44 [2] |
- |
Flushing |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
WSR 45 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
WSR 46 |
NM2 |
- |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Notes:
[1] This is a specific requirement for the
Castle Peak Power Station intake and the SS elevation should be maintained at
below 700 mg/L
[2] WSD¡¦s Water Quality Criteria for Flushing
Water at Sea Water Intakes has been adopted for seawater intake for flushing.
Values present in the table represent absolute values.
5.3.4
Hydrodynamic Modelling
Grid Refinement
5.3.4.1
The model adopted in the
previous approved HZMB BCF EIA has been reviewed and refined to simulate the
hydrodynamic and water quality impact for the construction and operational
phases in this study. The Delft3D-FLOW module was used for hydrodynamic
simulations. The grid layout is shown in Appendix 5.2a. Bathymetry data from electronic navigational
charts in 2011 from Marine Department was used to update the bathymetry in the
study area.
Modeling Parameter
5.3.4.2
The reference level of
the refined model is the principle Datum Hong Kong and the depth data is relative
to this datum.
5.3.4.3
The simulation period,
meteorological conditions, initial conditions and boundary conditions in the approved
Regional Update Model was adopted for the refined model. The typical simulation
was carried out for wet and dry seasons over a 15-day spring-neap tidal cycle with
spin-up period of at least 15 days.
5.3.4.4
The time step in
hydrodynamic model was set to 1 minute and the adequacy of adopted time step
could be verified from the stable results.
Model Validation
5.3.4.5
The grid properties of
the refined model are presented in Appendix 5.2a.
5.3.4.6
A validation process
has been conducted by checking the following parameters in the selected observation
points and main cross sections channels between the refined model and that Regional
Update Model.
Table
5.21 Validation
Matrix for Refined Model
Items
|
Parameters
|
Locations
(Appendix 5.2b) |
Cross-sections |
Accumulated Flow Salinity Flux |
Airport North |
Airport Channel |
||
BCF South |
||
Ma Wan |
||
Observation Points |
Current Velocity Current Direction |
WSR 22c - Tai Ho Wan Inlet
(outside) |
WSR 27 - San Tau Beach SSSI |
||
WSR 41 - Artificial Reef at NE Airport |
||
WSR 06 - Coral Communities at The Brothers Islands |
||
Map Results |
Velocity Vectors |
- |
5.3.4.7
The validation model result of the refined model
is shown in Appendix 5.2b. Modeling results indicate that the refined model generally
match with Regional Update Model. This further confirms that the refinement of
the model grid did not affect the model.
Model Scenarios
5.3.4.8
Table
5.22 summarizes the scenarios adopted for hydrodynamic modelling in this
study.
Table
5.22 Scenarios for Hydrodynamic Modeling for Construction and Operational
Phases
Scenario |
Hydrodynamic Regime |
Coastline / Bathymetry |
Purpose |
Sceanrio RUM ¡V Reference |
Reference Scenario |
•
Existing coastline |
For calibration |
Scenario H0 ¡V Base case |
Base scenario using refined model |
•
Existing coastline |
For calibration |
Scenario H1 ¡V Do-nothing |
Without project scenario in ultimate coastline
configuration using refined model |
•
Existing coastline plus HZMB HKBCF[3],
HZMB-HKLR[3], TM-CLKL[3], LLP (Siu
Ho Wan)[1], Sunny Bay Lung Kwu Tan and 3RS[2] ; •
Existing bathymetery plus KTCB[4]
and MDF[5]. |
For operational phase assessment without project
scenario |
Scenario H2 ¡V Operation Phase |
With project scenario in ultimate coastline
configuration using refined model |
•
TCE and Seafront for Road P1 Reclamation; •
Existing coastline plus, HZMB HKBCF[3],
HZMB-HKLR[3], TM-CLKL[3], LLP
(Siu Ho Wan)[1], Sunny Bay, Lung Kwu Tan and 3RS[2]; •
Existing bathymetery plus KTCB[4]
and MDF[5]. |
For operational phase assessment with project
scenario |
Scenario H3a-c
¡V Construction Phase - 3RS Implementation Schedule in their Approved
EIA |
With project scenario in different reclamation phases
and ultimate coastline configuration using refined model |
•
TCE and Seafront for Road P1 Reclamation
in construction month no. 15, 21 and 31 respectively plus existing coastline,
HZMB HKBCF[3],
HZMB-HKLR[3], TM-CLKL[3] and 3RS[2]; •
Existing bathymetery plus KTCB[4]
and MDF[5]. |
For construction phase assessment in construction
month no. 15, 21 and 31 respectively with 3RS implementation schedule in
their approved EIA (see Section 5.5.3) |
Scenario H3e-f
¡V Construction Phase Sensitivity Scenario for Possible Programme Slippage of 3RS |
With project scenario in different reclamation phases
and ultimate coastline configuration except 3RS reclamation using refined
model |
•
TCE and Seafront for Road P1 Reclamation
in construction month no. 15, 21 and 31 respectively plus existing coastline,
HKBCF[3], HKLR[3] and TMCLKL[3] ; •
Existing bathymetery plus KTCB[4]
and MDF[5]. |
For construction phase assessment in construction
month no. 15, 21 and 31 respectively for possible programme slippage of 3RS (see Section 5.5.3) |
Notes:
[1] LLP refers to Possible Lantau
Logistic Park. The project proponent of LLP has confirmed that there would be
no implementation schedule of LLP at this stage. Hence, the construction of LLP
has been excluded in the construction phase assessment. For conservative
assessment purpose, the LLP reclamation layout has been included in operation
phase. Since the reclamation layout of LLP is larger than the Siu Ho Wan reclamation layout
under the Study for Cumulative Environmental Impact
Assessment Study for the Three Potential Nearshore
Reclamation Sites in the Western Waters of Hong Kong, LLP layout has adopted.
[2] Layout of 3RS refers to EIA Report Expansion
of Hong Kong International Airport into a Three-Runway System (AEIAR-185/2014)
[3] Approved EIAs for HZMB HKBCF, HZMB HKLR and TM-CLKL
[4] Providing Sufficient Water Depth at Kwai Tsing Container Basin and
its Approach Channel (KTCB)
[5] Proposed
New Contaminated Mud Marine Disposal Facility at Airport East / East Sha Chau Area (MDF)
5.3.5
Water Quality Modeling
Modeling Parameters
5.3.5.1
The Delft3D-WAQ module was adopted for construction
and operational phase water quality modeling. The
hydrodynamic outputs from the model were coupled into the water quality module
for water quality simulation. The hydrodynamic forcing including averaged fresh
water flow, wind, initial conditions and boundary conditions for the dry and
wet seasons were applied separately in the corresponding hydrodynamic
simulation. Similarly, the pollution loads were applied in the corresponding
dry and wet season water quality simulations.
5.3.5.2
The modelling parameters adopted from the approved EIA for HZMB for
sedimentation and erosion of SS in construction phase are summarized in Table 5.23
Table
5.23 Parameters
for Water Quality Modeling in construction phase
Parameters |
Value |
Settling velocity |
0.5mm/s |
Critical stress for deposition |
0.2N/m2 |
Critical stress for erosion |
0.3N/m2 |
Minimum depth in which deposition can take
place. |
0.2m |
Model Scenarios
5.3.5.3
Table
5.24 summarizes the scenarios for water quality modeling.
Table
5.24 Scenarios for Water Quality Modeling
Scenario |
Description |
Hydrodynamic conditions |
Purpose |
Scenario 01 ¡V Do-nothing |
¡P
Water quality regime without the
project in place in ultimate coastline configuration ¡P
Corresponding to Scenario H1 in
hydrodynamics |
Scenario H1 |
Operational phase assessment without project scenario |
Scenario 02 ¡V Operational Phase |
¡P
Water quality regime with
project in place ¡P
Corresponding to Scenario H2 in
hydrodynamics |
Scenario H2 |
Operational phase assessment with project scenario |
Scenario 03a-c ¡V Construction Phase- 3RS Implementation Schedule in
their Approved EIA |
¡P
Water quality impact during
construction phase respectively with 3RS implementation schedule in their
approved EIA ¡P
Corresponding to Scenario H3a-c
in hydrodynamics |
Scenario H3 a-c |
Construction phase assessment in construction month no. 15, 21 and 31
respectively with 3RS implementation schedule in their approved EIA |
Construction Phase Sensitivity Scenario for Possible Programme Slippage of 3RS |
¡P
Water quality impact during
construction phase for possible programme slippage of 3RS ¡P
Corresponding to Scenario
H3e-f in hydrodynamics |
Scenario H3e-f |
Construction phase assessment for possible programme slippage of 3RS in
construction month no. 15, 21 and 31 |
5.4
Construction
Phase Assessment ¡V Land-based Works
5.4.1
Identification of Pollution Sources
5.4.1.1
Pollution sources from land-based construction
are summarized as follows:
¡P
General Construction Activities;
¡P
Sewage from Workforce;
¡P
Construction Works near Tung Chung Stream (including earthworks within CA
and CPA zonings);
¡P
Bridge Works at Tung Chung Stream;
¡P
Construction Work of Sewage Pumping Stations;
¡P
Construction Work of Fresh Water and Salt Water Reservoirs;
¡P
Construction of Storm water Management Facilities and Polder Scheme;
¡P
Groundwater and Runoff for Tunnel Works.
5.4.2
Prediction and Evaluation of Environmental
Impacts
5.4.2.1
Construction site runoff would come from all
over the works site. The surface runoff might be polluted by:
¡P
Runoff and erosion from site surfaces, earth working
areas and stockpiles;
¡P
Wash water from dust suppression sprays and
wheel washing facilities;
¡P
Chemicals spillage such as fuel, oil, solvents
and lubricants from maintenance of construction machinery and equipment; and
¡P Bentonite Slurries
5.4.2.2
Construction runoff may cause physical, biological and chemical effects.
The physical effects include potential blockage of drainage channels and
increase of suspended solid levels in the nearby WSRs. Runoff containing
significant amounts of concrete and cement-derived material may cause primary
chemical effects such as increasing turbidity and discoloration, elevation in
pH, and accretion of solids. A number of secondary effects may also result in
toxic effects to water biota due to elevated pH values, and reduced decay rates
of faecal micro-organisms and photosynthetic rate due
to the decreased light penetration.
5.4.2.3
Sewage effluents will be arisen from the
sanitary facilities provided for the on-site construction workforce. According
to Table T-2 of Guidelines for Estimating Sewage Flows for Sewage
Infrastructure Planning, the unit flow is 0.23 m3/day/employed population. The sewage is characterized by high levels of
BOD5, Ammonia and E. coli
counts.
5.4.3
Mitigation Measures
General Construction Activities
5.4.3.1
During the construction phase, a temporary
drainage system would be implemented to ensure that the surface run-off with
high concentration of suspended solid (SS) would not be discharged to Tung
Chung Stream. Runoff would need to pass through sedimentation tanks to reduce
the concentration of SS.
5.4.3.2
In accordance with the Professional Persons Environmental Consultative
Committee Practice Notes on Construction Site Drainage (ProPECC
PN 1/94), Environmental Protection Department, 1994, best management practices should
be implemented on site as far as practicable. The best practices are detailed below:
¡P
At the start of site establishment, perimeter
cut-off drains to direct off-site water around the site should be constructed
with internal drainage works. Channels, earth bunds or sand bag barriers should
be provided on site to direct stormwater to silt removal
facilities.
¡P
Diversion of natural stormwater
should be provided as far as possible. The design of temporary on-site drainage
should prevent runoff going through site surface, construction machinery and
equipment in order to avoid or minimize polluted runoff. Sedimentation tanks
with sufficient capacity, constructed from pre-formed individual cells of
approximately 6 to 8 m3 capacities, are recommended as a general
mitigation measure which can be used for settling surface runoff prior to
disposal. The system capacity shall be flexible and able to handle multiple
inputs from a variety of sources and suited to applications where the influent
is pumped.
¡P
The dikes or embankments for flood protection
should be implemented around the boundaries of earthwork areas. Temporary
ditches should be provided to facilitate the runoff discharge into an
appropriate watercourse, through a silt/sediment trap. The silt/sediment traps
should be incorporated in the permanent drainage channels to enhance deposition
rates.
¡P
The design of efficient silt removal
facilities should be based on the guidelines in Appendix A1 of ProPECC PN 1/94. The detailed design of the sand/silt traps
should be undertaken by the contractor prior to the commencement of
construction.
¡P
Construction works should be programmed to
minimize surface excavation works during the rainy seasons (April to
September). All exposed earth areas
should be completed and vegetated as soon as possible after earthworks have
been completed. If excavation of
soil cannot be avoided during the rainy season, or at any time of year when
rainstorms are likely, exposed slope surfaces should be covered by tarpaulin or
other means.
¡P
All drainage facilities and erosion and
sediment control structures should be regularly inspected and maintained to
ensure proper and efficient operation at all times and particularly following
rainstorms. Deposited silt and grit
should be removed regularly and disposed of by spreading evenly over stable,
vegetated areas.
¡P
If the excavation of trenches in wet periods
is necessary, it should be dug and backfilled in short sections wherever
practicable. Water pumped out from trenches or foundation excavations should be
discharged into storm drains via silt removal facilities.
¡P
All open stockpiles of construction materials
(for example, aggregates, sand and fill material) should be covered with
tarpaulin or similar fabric during rainstorms. Measures should be taken to
prevent the washing away of construction materials, soil, silt or debris into
any drainage system.
¡P
Manholes (including newly constructed ones)
should always be adequately covered and temporarily sealed so as to prevent
silt, construction materials or debris being washed into the drainage system
and storm runoff being directed into foul sewers.
¡P
Precautions to be taken at any time of year
when rainstorms are likely, actions to be taken when a rainstorm is imminent or
forecasted, and actions to be taken during or after rainstorms are summarized
in Appendix A2 of ProPECC PN 1/94. Particular
attention should be paid to the control of silty
surface runoff during storm events.
¡P
All vehicles and plant should be cleaned
before leaving a construction site to ensure no earth, mud, debris and the like
is deposited by them on roads. An
adequately designed and sited wheel washing facilities should be provided at
every construction site exit where practicable. Wash-water should have sand and silt
settled out and removed at least on a weekly basis to ensure the continued efficiency
of the process. The section of access
road leading to, and exiting from, the wheel-wash bay to the public road should
be paved with sufficient backfall toward the
wheel-wash bay to prevent vehicle tracking of soil and silty
water to public roads and drains.
¡P
Oil interceptors should be provided in the
drainage system downstream of any oil/fuel pollution sources. The oil
interceptors should be emptied and cleaned regularly to prevent the release of
oil and grease into the storm water drainage system after accidental spillage.
A bypass should be provided for the oil interceptors to prevent flushing during
heavy rain.
¡P
Construction solid waste, debris and rubbish
on site should be collected, handled and disposed of properly to avoid water
quality impacts.
¡P
All fuel tanks and storage areas should be
provided with locks and sited on sealed areas, within bunds of a capacity equal
to 110% of the storage capacity of the largest tank to prevent spilled fuel
oils from reaching water sensitive receivers nearby.
¡P
Regular environmental audit on the construction
site should be carried out in order to prevent any malpractices. Notices should be posted at conspicuous
locations to remind the workers not to discharge any sewage or wastewater into
the water bodies, mangroves and open sea.
Sewage from Workforce
5.4.3.3
Portable chemical toilets and sewage holding
tanks should be provided for handling the construction sewage generated by the
workforce. A licensed contractor should be employed to provide appropriate and
adequate portable toilets to cater for 0.23 m3/day/employed population and be responsible for appropriate disposal and
maintenance. Since
temporary sanitary facilities e.g. portable chemical toilets, and sewage
holding tank will be provided, no adverse water quality impact is anticipated.
5.4.3.4
Notices should be posted at conspicuous
locations to remind the workers not to discharge any sewage or wastewater into
the nearby environment during the construction phase of the Project. Regular
environmental audit on the construction site should be conducted in order to provide
an effective control of any malpractices and achieve continual improvement of
environmental performance on site. It is anticipated that sewage generation
during the construction phase of the Project would not cause water quality
impact after undertaking all required measures.
5.4.3.5
By adopting the best management practices, it
is anticipated that the impacts from land-based construction will be reduced to
satisfactory levels before discharges. The details of best management practices
will be highly dependent to actual site condition and Contractor shall apply
for a discharge license under WPCO.
Construction Works
near Tung Chung Stream
5.4.3.6
There will be development near Tung Chung
Stream. According to the RODP, a 30m buffer zone for
the natural sections of Tung Chung Stream and a 20m buffer zone for the major
tributary near Ngau Au will be zoned as ¡§CA¡¨, ¡§CPA¡¨,
or ¡§OU¡¨ (for polders and the future River Park), except the road crossing
locations. Precast structures or other similar approaches
will be used to minimize the pollution from construction works to Tung Chung
Stream. Some earthworks would also be required within the CA and CPA zonings. Good
site management as stipulated in ProPECC PN1/94 will
be fully implemented so that the treated runoff will be discharged to public
drainage system in compliance with the WPCO. Adverse impact on Tung Chung
Stream is not anticipated.
Bridge Works at Tung
Chung Stream
5.4.3.7
The local distributors will be extended to
connect to existing villages like Ngau Au, Lam Che, Nim Yuen and Mok Ka. Although a few sections
of these local distributors (in a form of bridge deck) will have to span over
the Tung Chung Stream and its tributaries, only the footings of the bridge
deck, which are considerably smaller in size, will be located within the area
above high water mark of the buffer zone. Considered that there is only
relatively limited works for the footing construction and the area affected
would likely be the area above high water mark with relatively less disturbance
on ecological habitat. Good site management as stipulated in ProPECC PN1/94 will be fully implemented so that the
treated runoff will be discharged to public drainage system in compliance with
the WPCO. Adverse impact on Tung Chung Stream is not anticipated.
Construction Work of
Sewage Pumping Stations
5.4.3.8
Five new sewage pumping stations (SPSs) and one
upgraded SPS are proposed for this project as shown in Figure 2.2 and Figure 2.3.
Two proposed SPSs are located in Tung Chung East. Three proposed SPSs and one
upgraded SPS are located in Tung Chung West and Tung Chung Valley. A 30m buffer zone for the natural sections of Tung Chung Stream and
a 20m buffer zone for the major tributary near Ngau
Au will be zoned as ¡§CA¡¨, ¡§CPA¡¨, or ¡§OU¡¨ (for polders and the future River
Park), except the road crossing locations to prevent any
construction works near river and thus to avoid any direct water quality impact
to Tung Chung Stream. Good site management as stipulated in ProPECC
PN1/94 will be fully implemented so that the treated runoff will be discharged
to public drainage system in compliance with the WPCO. Adverse water quality
impact is not anticipated.
Construction Work of Fresh Water and Salt Water
Reservoirs
5.4.3.9
Although part of the site had
been formed decades ago, construction work for the fresh water and salt water
reservoirs would still cause certain water quality impacts. The major
construction works will include typical earthwork, concrete works for service reservoir
structures, pipeworks and modification work to
existing access road. Both cut-and-fill slopes
shall be formed for the formation of platform for the service reservoirs
construction and for the modification work to existing access road. Good
site management as stipulated in ProPECC PN1/94 will
be fully implemented so that the treated runoff will be discharged to public
drainage system in compliance with the WPCO. Adverse water quality impact is
not anticipated.
Construction of Storm
Water Management Facilities and Polder Scheme
5.4.3.10 The
polder scheme proposed in Tung Chung West as part of the flood protection
measures will be generally in form of an earth bund less than approximate 1.5m
in height while the stormwater
attenuation and treatment ponds will be in form of normal water pond with
various depth and planting for sedimentation and water treatment purpose. The
works involve earthwork, laying of lining and some
water pipe laying works. Suitable landscaping works would also be implemented
for the polders and stormwater
attenuation and treatment ponds. Good site management as stipulated in ProPECC PN1/94 will be fully implemented so that the
treated runoff will be discharged to public drainage system in compliance with
the WPCO. Adverse water quality impact is not anticipated.
Groundwater and Runoff
for Tunnel Works
5.4.3.11
As discussed in Chapter 2,
the proposed railway alignment and new stations are separate projects to be
implemented by the future rail operator. However, this EIA has also considered their
cumulative impacts based on reasonable assumptions. Tunnel Boring Method (TBM)
is considered for the construction of part of the railway tunnel to pass
underneath the existing Man Wan Chung bay area and also underneath the hill
crests to the northeast of Ma Wan Chung. Ground treatment
such as grouting will be carried out prior to bored tunnelling. The intrusion of groundwater during bored tunnelling would therefore be insignificant.
5.4.3.12
Cut-and-Cover method would be adopted for the
underpass at Road D1 in Tung Chung East, which involving trench-excavation
(i.e. open-cut) followed by in-situ construction of the tunnel structures. Construction
methodology using diaphragm wall techniques can minimise
the intrusion of groundwater during excavation. It involves excavation of a
narrow trench that is kept full of slurry, which exerts hydraulic pressure
against the trench walls and acts as a shoring to prevent collapse. Slurry trench excavations can be
performed in all types of soil, even below the ground water table.
5.4.3.13 During tunnelling work, rainfall, surface runoff and groundwater seepage pumped out from the tunnel would have high SS content. The situation would be worse during wet seasons. Surface runoff may also be contaminated by bentonite and grouting chemicals that would be required for the tunneling works and diaphragm walls for cut-and-cover tunnel sections. In addition, wastewater from tunnelling works will also contain a high concentration of SS. Good site management as stipulated in ProPECC PN1/94 will be fully implemented by the rail operator so that the treated runoff will be discharged to public drainage system in compliance with the WPCO. Adverse water quality impact is not anticipated.
5.4.4
Residual Impacts
5.4.4.1
No residual land-based water quality impacts
are anticipated during construction with the above mitigation measure
implemented.
5.5
Construction
Phase Assessment ¡V Marine-based Works
5.5.1
Summary of Construction Methodology for Marine
Works
Reclamation
5.5.1.1
As discussed in
Section 2.7, non-dredged
approach for the reclamation in TCE, has been
recommended to minimise environmental impacts. However, while dredging work has
been preferably avoided, filling work would be inevitable. The actual
construction sequences and processes of main reclamation filling shall be
further developed by the contractor but the envisaged construction processes of
the adopted drained reclamation are summarised below:
1.
Installation of the silt curtain;
2.
Laying of geotextile and sand blanket over the marine deposit (i.e. over
the existing seabed) prior to reclamation filling;
3.
Installation of band drains by marine based method to accelerate the
consolidation of marine sediment;
4.
Construction of seawall to allow at least 200m leading edge before
reclamation filling;
5.
Underwater filling from sand blanket to +2.50mPD;
6.
Land filling from +2.50mPD to formation level; and
7.
Surcharging (including construction and removal)
Seawall Construction
5.5.1.2
The details of construction sequences and
processes for seawalls shall be further developed by the contractor but the
envisaged construction processes of the adopted seawall options are summarized
below.
5.5.1.3
The envisaged construction processes for pipe
pile type non-dredged seawall supported by stone column are listed as follows.
To minimize the water quality impact during the seawall construction, the
reclamation work would normally be commenced after the adjacent seawalls (~200m
in length) are completed.
1.
Installation of the silt curtain;
2.
Lay geotextile and deposit rock fill (gravel) blanket;
3.
Install stone columns by marine based plant;
4.
Install pipe pile structures;
5.
Fill inside pipe pile structures;
6.
Install corrosion protection system (if necessary) and construct capping
beam;
7.
Construct sloping berm in front of pipe pile structure (as necessarily).
5.5.2
Identification of Pollution Sources
Stone Column
Installation
5.5.2.1
Stone columns will be installed prior to
seawall construction and to accelerate the settlement and improve the strength
of marine deposits and foundation of temporary reclamation. The stone columns
will be installed under seabed levels both inside and outside the seawall and a
geotextile layer will be installed to cover the seabed to prevent re-suspension
and seabed disturbance. A silt curtain will be deployed to surround the stone
column working vessels during installation. In addition to the perimeter silt
curtain to the entire marine works area, minor disturbance to water column is
anticipated during installation/removal of jet. Good site practice such as
regular inspections is considered adequate to minimize the water quality
impact.
5.5.2.2
According to the EM&A reports (Mar 2012 to
Jun 2014) under the HZMB project, satisfactory performance in terms of water
quality was observed during stone column installations. Similar operation will
be adopted for this study and adverse water quality impact is therefore not
anticipated.
Deep Cement Mixing
5.5.2.3
For ground improvement, a combination of
methods including prefabricated vertical drains (PVD), deep cement mixing
(DCM), stone columns, steel cells, vertical sand drains and sand compaction
piles may be adopted at different locations depending on geotechnical as well
as environmental constraints. According to 3RS EIA, overseas application and
the local site trial of DCM held in February 2012 has demonstrated that there is
no adverse water quality impact associated with this construction method. The
findings of the DCM trial concluded that the DCM installation works did not
result in any deterioration in marine water quality,
and no leakage of contaminants during the course of the DCM trial.
Construction Work of
Proposed Marina
5.5.2.4
A marina with an accommodation of 95 berths is
proposed at the northern tip of TCE along the waterfront promenade. The worst
scenario of SS impact from marine-based construction work which has a much
higher SS release rate in filling activities has been considered in Table 5.27d. Floating silt curtain
shall be deployed for all marine works to minimize the SS impact to the marine
water. Adverse water quality impact is not anticipated.
Marine Traffic
5.5.2.5 During construction phase, marine traffic for the transportation of construction materials for reclamation is anticipated to increase. The induced number of marine vessels during construction phase may impact the marine water quality. The potential water quality impacts include sewage generated by the workers and accidental spillage of chemicals / chemicals waste into the marine environment. The potential impact associated with sewage generated by the workforce can be readily controlled by the provision of adequate sanitary facilities such as portable chemical toilets on the marine vessels. The storage and disposal of chemical waste should follow the guidelines stipulated in the Waste Disposal (Chemical Waste) (General) Regulations. Water quality impacts due to the increase in marine traffic is not anticipated. Besides, overflow of filling materials in the barges or hoppers can cause water pollution during loading or transportation. Good management practice such as limiting the capacity of a barge such that no overflow of filling material can minimise the potential water quality impact.
Reclamation Works of Tung Chung East and Seafront
Works for Road P1
5.5.2.6
According to the
construction programme, reclamation work of TCE and
seafront works for Road P1 will start from 2018 Q1 to 2021 Q4. The reclamation
work of Road P1 includes a narrow strip of reclamation of approximately 30m
wide for the section connecting TCE to Siu Ho Wan.
Construction Sequence
5.5.2.7
The schematic diagram
of key construction phases are presented in Appendix 5.4a. As
shown in the diagram, leading seawall of 200m would be formed in advance of reclamation filling.
5.5.2.8 The seawall option mentioned in Section 5.5.1.2 mainly consists of a pipe-pile structure with a sloping berm. Public fill is proposed to be used inside the pipe-pile structures and hence, the filling works is expected to be confined within the pipe-pile structures and adverse water quality impact is not anticipated. The pipe-piles will be interlocking to each other for structural stability. No release of sediment in between the pipe-piles during land reclamation is anticipated. The sediment reduction rate by the pipe-pile seawall would be similar to that by the conventional seawall structure.
5.5.2.9
For the sloping berm in front of the pipe-pile structure, a layer of
rock blanket will be placed followed by stone column as the foundation of the
berm. The core of the sloping berm will be formed by rock fill. Underlayer in the form of relatively larger grading of rock
fill will be placed on top of core as the protection of the core and interface
material between the core and the covering rock armour. The sloping berm will
be covered up by rock armour as a protection against the wave action and
erosion. Since no fine content in the rock fill is expected, SS impact is not
anticipated from rock fill.
5.5.2.10
The construction materials proposed for the underwater filling includes
a 2m thick sand blanket using sand fill which is followed by public fill up to
+2.5mPD. According to the latest construction methodology, the
filling rates for public fill and sand blanket for reclamation works are assumed
in Table 5.25. The proportion of sand fill and
public fill in different construction stage is presented in Appendix
5.4a.
An example of calculation of SS release from sand fill and public fill is also
given. The working hours for filling activities is assumed from 8:00 to 18:00.
Table
5.25 Estimated
filling rates for public fill and sand blanket
Filling Material |
Estimated filling volume per quarter of a year |
Estimated filling rate m3 per day[1] |
Public Fill |
1,040,000 |
16,000 |
Sand blanket |
409,370 |
6,200 |
Note:
[1] The estimated filling
rate is calculated based on 22 working days per month, however 7 working days
per week is assumed in the modelling for conservative assessment.
Sediment Loss
5.5.2.11
Table
5.26 summarizes the fine contents and bulk density of filling materials,
sand and public fill. The sediment loss rate for public fill and sand blanket
is assumed to be 5% of fine content percentage in filling materials (< 63µm)
and sediment reduction due to leading seawall is assumed to be 45% from HZMB
EIA.
Table
5.26 Filling
Material Properties
Filling Material |
Fine Contents |
Bulk Density |
Sand |
5% |
1,680 kg/m3 |
Public Fill |
25% |
1,900 kg/m3 |
Source: EIA ¡V HZMB HKLR
5.5.3
Consideration of Concurrent Projects in
Construction Phase
5.5.3.1
The assessment years for the
construction phase of Tung Chung Reclamation is from Yr
2018 to Yr 2021. The concurrent projects considered
in the construction phase are summarized in Table 5.27a. As most of the marine works for HZMB HKBCF, HZMB HKLR
and TM-CLKL will be completed by 2016, the land boundary was included in this
study. The bathymetry for KTCB and MDF was included in this study. The sediment
release rates for 3RS, Contaminated Mud Pit at East Sha
Chau (ESC) CMPs and Tung Chung reclamation (TCE and
Road P1) are shown in Appendix 5.4a for comparison. Table 5.27b summarizes the findings. Based on the filling
programme, the sediment release rate during construction is shown in Appendix 5.4a. As
shown in the appendix, there is no overlapping with the 3RS marine construction
activities. However, overlapping with CMP activities is identified. The
cumulative impact from CMP has been incorporated in the construction phase
assessment.
Table 5.27a Summary of concurrent projects in construction phase
Proposed/Planned Project in the Vicinity |
Tentative Implementation Programme |
Status & Consideration in This Study |
Hong Kong - Zhuhai -
Macao Bridge Hong Kong Boundary Crossing Facilities (HZMB HKBCF, being
constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. |
Tuen Mun
- Chek Lap Kok Link
(TM-CLKL, being constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. |
Hong Kong - Zhuhai -
Macao Bridge Hong Kong Link Road (HZMB HKLR, being constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. |
Expansion of Hong Kong
International Airport into a Three-Runway System (3RS) |
Construction in marine
works for 2015 Q2 to 2017 Q3 To be commissioned by
2023 |
(i) 3RS in the
original EIA programme: Land boundary was
included in the study. No SS release from
3RS. (ii) Possible
programme slippage of 3RS: SS release from 3RS
reclamation was included. No land formed in the
3RS area. |
Providing Sufficient
Water Depth at Kwai Tsing
Container Basin and its Approach Channel (KTCB) |
To be commissioned by
2016 |
EP (EP-426/2011/A) was issued. The bathymetry was included in this study. |
Proposed New
Contaminated Mud Marine Disposal Facility at HKIA East/East Sha Chau Area (MDF) |
To be commissioned by
2016 |
EP (EP-427/2011/A and EP-312/2008/A) was issued. The SS release and bathymetry was included
in this study. |
5.5.3.2 According to the latest EM&A schedule of ESC CMPs (Aug 2015) in Appendix 5.4a, there is either backfilling or capping work in ESC CMPs from Yr 2016. The SS release rate in East Sha Chau (ESC) CMPs is therefore calculated based on a dredging/disposal rate of 600 tonne/day. Based on the information from the project proponent of CMPs, capping in South Brothers (SB) CMPs will be completed in Yr 2017 and forecast of works in East Sha Chau (ESC) CMPs are summarized in Table 5.27c. The total SS release rate estimated for ESC CMPs is about 158 tonne/day, taking into account of dredging, backfilling and capping activities, which is smaller than 600 tonne/day adopted in the assessment. The above modelling assumption is on conservative side for prudent sake. In the real situation, the rate of backfilling and capping depends on the other project proponents for dumping of contaminated and clean mud. The modelled worst case cumulative impact is thus very unlikely to be representative of the average daily disposal rates.
Table
5.27b Sediment release rates of public fill and sand fill with concurrent projects
Projects |
Duration |
Estimated sediment release rate (tonne/day) |
Tung Chung Reclamation (TCE and Road P1) |
2018 Q1 to 2021 Q4 |
206 [1] |
Contaminated Mud Pit at East Sha Chau (CMP) |
From 2016 to 2023 |
600 |
3RS |
2015 Q2 to 2017 Q4 |
4349[2] |
Notes:
[1] For unmitigated scenario, detailed calculation
of sediment release rate is presented in Appendix 5.4a.
[2] Based on the Scenario Yr 2017 in Appendix 8.6
of 3RS EIA.
Table
5.27c Estimated SS release rate (tonne/day) for ESC
CMPs *
|
2018 |
2019
Q1 |
2019
Q2-Q4 |
2020 |
2021 |
Dredging |
|
121 |
|
|
|
Backfilling |
37 |
18 |
18 |
18 |
18 |
Capping |
37 |
18 |
18 |
12 |
12 |
Total |
74 |
158 |
37 |
31 |
31 |
Note:
* The estimated SS
release rate (tonne/day) for ESC CMP is dervided from CEDD information and
presented in Appendix 5.4a.
5.5.3.3
According to the sediment release rate diagram
in Appendix 5.4a. Table 5.27d summarizes the key
construction months selected for water quality modelling.
Table
5.27d Description of selected construction months
Months |
Description |
15 |
Commencement of construction. Sediment release rate is highest between
2018 Q3 ¡V Q4. Construction of western seawall is partially completed, which
may affect the hydrodynamics in the vicinity. |
21 |
Construction of western seawall is completed and east seawall is
partially completed, which may affect the hydrodynamics in the vicinity. |
31 |
Construction of eastern seawall is completed. Sediment release rate is
highest between 2020 Q1 ¡V 2021 Q2 |
5.5.4
Water Quality Modelling Scenarios of SS Impact
in Construction Phase
5.5.4.1
The water quality modelling scenarios of SS
Impact in Construction Phase are summarized below:
¡P
Scenario 03a ¡V Unmitigated Scenario: SS impacts from reclamation work of TCE and seafront works for Road
P1 only without mitigation measure.
¡P
Scenario 03b ¡V Mitigated Scenario: SS impacts from reclamation work of TCE and seafront works for Road
P1 only with mitigation measure.
¡P Scenario 03c - Cumulative SS impacts from Mitigated Scenario of Tung Chung project and concurrent projects if 3RS Implementation Schedule in their Approved EIA.
¡P
Scenario 03c +3RS ¡V Sensitivity Scenario
for possible programme slippage of 3RS.
5.5.5
Modelling Results of Unmitigated Scenario
5.5.5.1 For Scenario 03a, the predicted maximum elevations in SS at all of the observation points are summarised in Tables 5.28a - Tables 5.28c for construction month numbers 15, 21 and 31. The predicted SS extents are shown in Appendix 5.4b. According to the modelling results of Scenario 03a, it is observed that the plume due to construction is localised and constrained by part of the western seawall and the SS plume would be extended to the eastern side. Exceedance of SS criteria is observed at WSR 22c (Tai Ho Wan Inlet (outside)) in the bottom layer in construction month 15 during wet season. The highest SS elevation (i.e. 4.50 mg/L) is predicted at WSR 22c (Tai Ho Wan Inlet (outside)) in the bottom layer.
5.5.6
Modelling Results of Mitigated Scenario
5.5.6.1 As exceedance of SS levels is observed at WSR 22c (Tai Ho Wan Inlet (outside)) for the unmitigated Scenario 03a, silt curtain is proposed to contain the sediment (i.e. Scenario 03b). The removal efficiency of single floating silt curtain is taken as 45% in accordance with HZMB EIA. The predicted maximum elevations in SS with mitigation measures at observation points are summarised in Tables 5.29a - Tables 5.29c for construction month number 15, 21 and 31 respectively.
5.5.6.2 The predicted SS extents are shown in Appendix 5.4b. Full compliance with SS criteria at identified WSRs has been predicted and adverse water quality impact is therefore not anticipated. Similar to the Scenario 03a result, the highest SS elevation (i.e. 2.48 mg/L) occurs at WSR 22c (Tai Ho Wan Inlet (outside)) in the bottom layer in construction month 15 of wet season. With the implementation of mitigation measures, the SS elevation is within its corresponding criteria level of 2.9 mg/L.
5.5.7
Modelling Results of Mitigated Scenario with Concurrent
Projects
3RS Implementation
Schedule in their Approved EIA
5.5.7.1
For Scenario 03c, the
predicted cumulative maximum elevations in SS at selected observation points due
to concurrent projects, including New Contaminated Mud Marine Disposal Facility
at Airport East / East Sha Chau
Area, are summarised in Tables 5.30a -
Tables 5.30c for construction month number 15, 21 and 31 respectively. The
predicted SS plume extent is shown in Appendix 5.4b. Exceedance
is observed at the following WSRs.
WSR |
Season |
Layers |
Month |
WSR04 (Marine Parks at Brothers Islands and
Tai Mo To (Dolphin Habitat)) |
Dry |
surface, middle, bottom, depth-averaged |
15,21 and 31 |
Wet |
surface, middle, bottom, depth-averaged |
15,21 and 31 |
|
WSR 06 (Coral Communities at The Brothers
Islands) |
Dry |
surface, middle, bottom, depth-averaged |
15,21 and 31 |
Wet |
surface, middle, bottom, depth-averaged |
15,21 and 31 |
5.5.7.2 On comparing Scenario 03b (Table 5.29a-c) with Scenario 03c (Table 5.30a-c), the exceedance is dominated by the sediment released from CMP, but not from the proposed project. It should however be noted that the maximum disposal rate in the EP of the CMP either backfilling or capping work have been adopted in this cumulative assessment in order to introduce conservative assumptions in the assessment. Based on the information from the project proponent of CMPs, the estimated total SS release rate estimated for ESC CMPs is about 158 tonne/day (Table 5.27c), taking into account of dredging, backfilling and capping activities, which is smaller than 600 tonne/day adopted in the assessment. According to the conservative assessment, the results reveal that the project contribution would be the highest in Month 31. At WSR 06 (Coral Communities at The Brothers Islands) in Month 31, the cumulative SS concentration is 7.39 mg/L and 4.38 mg/L in dry and wet season, which exceeds the depth-averaged criteria 3.9 mg/L and 2.5 mg/L by 13% and 75% respectively. However, the SS contribution from the present project is 0.00 mg/L and 0.09 mg/L in dry and wet season, which accounts for 0.00% and around 2% of the cumulative contribution respectively. Further analysis has been conducted for the observation point M2, which is at the west boundary of Brothers Islands Marine Park and nearest to ESC CMPs. Results reveal that in Month 31 the cumulative SS concentration is 12.9 mg/L and 6.40 mg/L in dry and wet season respectively, which is higher than that at WSR 06, as it is closer to the ESC CMPs. The SS contribution from the present project is 0.00 mg/L and 0.02 mg/L in dry and wet season at M2, which accounts for 0.00% and 0.3% of the cumulative contribution respectively.
5.5.7.3 In the real situation, the progress of the disposal and capping activities depend on the disposal demand from various marine works projects in Hong Kong. The estimated total SS release rate 158 tonne/day is much lower than the modelled worst case, i.e. 600 tonne/day (26,700 m3/day). The exceedance at WSR04 (Marine Parks at Brothers and Tai Mo To (Dolphin Habitat)) and WSR 06 (Coral Communities at The Brothers Islands) in the modelled worst case cumulative impact is thus very unlikely. However, the CMP construction schedule will be kept review.
Sensitivity
Scenario for Possible Programme Slippage of 3RS
5.5.7.4 As shown in Table 5.27b and Appendix 5.4a, programme of the marine work for Tung Chung project and 3RS will not be overlapped based on the approved 3RS EIA. However, given the current circumstance; the 3RS implementation and there may be potential slippage of their construction programme. In order to consider the potential slippage of construction programme of 3RS, a sensitivity scenario was carried out to predict the cumulative SS elevation.
5.5.7.5 According to the 3RS EIA, two construction stages Year 2016 Scenario and Year 2017 Scenario were modeled. Although the sediment release rate in Year 2017 Scenario is higher than that in Year 2016 Scenario, the SS dispersion extent in Year 2016 Scenario is closer to the Project. Hence, the 3RS configuration in Year 2016 Scenario is adopted, which there would be no land formed in the 3RS area.
5.5.7.6 Besides, under 2016 scenario of 3RS construction, sand blanket and ground improvement for reclamation, water jetting and dredging for diversion of 11kv submarine cable were considered. According to the 3RS EIA, the SS release rates are summarized in Table 5.27e.
Table
5.27e Summary of SS
release rates of 3RS construction
Scenario
Type |
Work
Type |
Sediment
release rate (kg/s) |
Reclamation
in 2016 |
sand
blanket |
0.995 |
ground
improvement |
1.06 |
|
Diversion
of 11kv submarine cable |
water
jetting |
2.813 |
dredging |
0.167 |
5.5.7.7
The predicted SS elevation
is summarised in Tables 5.30d - Tables
5.30e for construction month number 15, 21 and 31 respectively. The
predicted SS plume extent is shown in Appendix 5.4b. Exceedance
is observed at the following WSRs.
WSR |
Season |
Layers |
Month |
WSR06 (Coral
Communities at The Brothers Islands) |
Dry |
middle, bottom,
depth-averaged |
15,21 and 31 |
Wet |
middle, bottom,
depth-averaged |
15 and 21 |
|
surface, middle,
bottom, depth-averaged |
31 |
||
WSR 25 (Cooling
water intake at Hong Kong International Airport (North)) |
Dry |
middle, bottom |
15,21 and 31 |
Wet |
middle, bottom,
depth-averaged |
15,21 and 31 |
5.5.7.8 At WSR04 (Marine Parks at Brothers and Tai Mo To (Dolphin Habitat)), exceeedance is observed in Scenario 03c (Table 5.30a-c), but not in the Scenario 03c with 3RS (Table 5.30d-f). This is because the hydrodynamics is changed under the landform in 3RS reclamation. The extent of SS plumes released from ESC CMPs towards the Brothers Islands are changed. The SS level at WSR04 does not exceed in the sensitivity scenario. This is corresponding to the result that no exceedance in principal criteria (depth-averaged) in 3RS EIA at WSR named E4.
5.5.7.9 While the exceedance at WSR06 (Coral Communities at The Brothers Islands) is due to CMP project, exceedance at WSR 25 (Cooling water intake at Hong Kong International Airport (North)) is contributed by 3RS construction. In the real situation, the rate of backfilling and capping depends on the other project proponents for dumping contaminated mud in backfilling or clean mud in capping, the CMP construction schedule will be kept review.
5.5.7.10 Exccedance at cooling water intake at Hong Kong International Airport (North) (named C7a in 3RS EIA) was also predicted in 3RS EIA. As stated in 3RS EIA, additional mitigation measures such as double silt curtains by 3RS Project Proponent and/or silt screens around the intakes were recommended. With the adoption of these additional mitigation measures, cumulative SS levels due to 3RS construction will be reduced to acceptable levels.
5.5.7.11 The SS conc at the observation point M6 and M10 near the southwest boundary of Sha Chau and Lung Kwu Chau Marine Park (SC & LKC MP) would increase due to the 3RS construction. At the southeast boundary of SC & LKC MP, the SS level at observation point M9 is lower than that of Scenario 03c (i.e. cumulative impact of ESC CMPs if 3RS implementation schedule). This is because the hydrodynamics is changed under the landform in 3RS reclamation and the extent of SS plumes released from ESC CMPs will divert towards the observation point M9. However, the cumulative SS conc at WSR 10 (Sha Chau and Lung Kwu Chau Marine Park) and WSR 42 (Artificial Reef and coral communities at Sha Chau) would comply with the SS criteria.
Table
5.28a Predicted
Maximum Suspended Solids (mg/L) Elevations (Unmitigated, Scenario 03a) at
Construction Month 15
WSR
|
Modeling Result
|
Suspended
Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.55 |
0.70 |
0.75 |
0.68 |
0.01 |
0.01 |
0.03 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.29 |
0.38 |
0.41 |
0.37 |
0.00 |
0.00 |
0.01 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
0.09 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
0.04 |
0.04 |
0.04 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.02 |
0.02 |
0.03 |
0.02 |
0.01 |
0.02 |
0.09 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.24 |
0.38 |
1.13 |
0.41 |
0.28 |
1.78 |
4.50 |
2.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR25 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.02 |
0.02 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.02 |
0.02 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.03 |
0.03 |
0.03 |
0.03 |
0.00 |
0.00 |
0.01 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.06 |
0.07 |
0.08 |
0.07 |
0.01 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.03 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.00 |
0.00 |
0.01 |
0.00 |
0.03 |
0.05 |
0.07 |
0.05 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.00-0.01
mg/L for dry season and 0.01-0.04 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be around 0.00 mg/L for both dry season and wet season. The
details are presented in Appendix 5.4b.
Table
5.28b Predicted
Maximum Suspended Solids (mg/L) Elevations (Unmitigated, Scenario 03a) at
Construction Month 21
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.02 |
0.03 |
0.03 |
0.03 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.02 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
0.09 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.03 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
0.02 |
0.09 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
0.00 |
0.01 |
0.01 |
0.01 |
0.02 |
0.03 |
0.05 |
0.03 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.00 |
0.01 |
0.01 |
0.00 |
0.02 |
0.03 |
0.04 |
0.03 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.00 |
0.01 |
0.02 |
0.01 |
0.01 |
0.03 |
0.07 |
0.03 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.00 |
0.01 |
0.02 |
0.01 |
0.01 |
0.02 |
0.02 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.00-0.04
mg/L for dry season and 0.00-0.24 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be around 0.00 mg/L for both dry season and wet season. The
details are presented in Appendix 5.4b.
Table
5.28c Predicted Maximum
Suspended Solids (mg/L) Elevations (Unmitigated, Scenario 03a) at Construction
Month 31
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.04 |
0.04 |
0.05 |
0.04 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.02 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.01 |
0.01 |
0.02 |
0.01 |
0.05 |
0.39 |
0.83 |
0.42 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.01 |
0.01 |
0.00 |
0.02 |
0.08 |
0.57 |
0.17 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.00 |
0.01 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.01 |
0.02 |
0.03 |
0.02 |
0.14 |
0.16 |
0.18 |
0.16 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.07 |
0.25 |
0.10 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
0.02 |
0.12 |
0.17 |
0.10 |
0.25 |
0.47 |
0.65 |
0.37 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.03 |
0.06 |
0.10 |
0.06 |
0.24 |
0.43 |
0.48 |
0.37 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.03 |
0.14 |
0.26 |
0.13 |
0.10 |
0.33 |
1.02 |
0.40 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.05 |
0.09 |
0.14 |
0.10 |
0.01 |
0.02 |
0.10 |
0.03 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.02 |
0.05 |
0.09 |
0.05 |
0.14 |
0.23 |
0.27 |
0.21 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.00-0.77
mg/L for dry season and 0.04-3.09 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 0.00-0.01 mg/L for dry season and 0.00-0.01 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.29a Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated, Scenario 03b) at
Construction Month 15
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.30 |
0.38 |
0.41 |
0.37 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.16 |
0.21 |
0.23 |
0.20 |
0.00 |
0.00 |
0.01 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.05 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
0.02 |
0.02 |
0.02 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.01 |
0.01 |
0.02 |
0.01 |
0.00 |
0.01 |
0.05 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.13 |
0.21 |
0.62 |
0.23 |
0.16 |
0.98 |
2.48 |
1.11 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.02 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.03 |
0.04 |
0.04 |
0.04 |
0.00 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.00 |
0.00 |
0.01 |
0.00 |
0.02 |
0.03 |
0.04 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the predicted
maximum suspended solids elevations in depth averaged would be 0.00-0.01 mg/L
for dry season and 0.00-0.02 mg/L for wet season. The details are presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be around 0.00 mg/L for both dry season and wet season. The
details are presented in Appendix 5.4b.
Table
5.29b Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated, Scenario 03b) at
Construction Month 21
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.01 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.05 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.05 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
0.00 |
0.01 |
0.01 |
0.00 |
0.01 |
0.02 |
0.03 |
0.02 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.02 |
0.01 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.00 |
0.01 |
0.01 |
0.01 |
0.00 |
0.02 |
0.04 |
0.02 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Notes
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.00-0.02
mg/L for dry season and 0.00-0.13 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be around 0.00 mg/L for both dry season and wet season. The
details are presented in Appendix 5.4b.
Table
5.29c Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated, Scenario 03b) at
Construction Month 31
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.02 |
0.02 |
0.03 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
0.00 |
0.01 |
0.01 |
0.01 |
0.03 |
0.22 |
0.45 |
0.23 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.04 |
0.31 |
0.09 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
0.01 |
0.01 |
0.01 |
0.01 |
0.08 |
0.09 |
0.10 |
0.09 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.04 |
0.14 |
0.05 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
0.01 |
0.07 |
0.09 |
0.05 |
0.14 |
0.26 |
0.36 |
0.20 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
0.02 |
0.03 |
0.05 |
0.03 |
0.13 |
0.24 |
0.27 |
0.20 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
0.02 |
0.08 |
0.14 |
0.07 |
0.05 |
0.18 |
0.55 |
0.22 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.03 |
0.05 |
0.08 |
0.05 |
0.01 |
0.01 |
0.05 |
0.02 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
0.01 |
0.03 |
0.05 |
0.03 |
0.08 |
0.13 |
0.15 |
0.12 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Notes:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.00-0.43
mg/L for dry season and 0.02-1.70 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be around 0.00 mg/L for dry season and 0.00-0.01 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30a Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project, Scenario
03c) at Construction Month 15
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.30 |
0.39 |
0.41 |
0.37 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.16 |
0.21 |
0.23 |
0.20 |
0.00 |
0.00 |
0.01 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
3.05 |
6.30 |
7.22 |
5.74 |
2.71 |
3.54 |
3.58 |
2.82 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR05a |
0.92 |
1.40 |
1.42 |
1.19 |
0.68 |
0.84 |
1.29 |
0.82 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.26 |
0.60 |
0.29 |
0.44 |
0.68 |
0.89 |
0.64 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
3.69 |
8.31 |
10.54 |
7.35 |
3.09 |
4.67 |
6.07 |
4.38 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.70 |
1.04 |
1.41 |
0.94 |
0.52 |
0.83 |
1.12 |
0.83 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.66 |
1.26 |
1.41 |
1.15 |
0.41 |
0.90 |
1.19 |
0.77 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.61 |
2.59 |
4.35 |
2.20 |
0.17 |
1.36 |
3.34 |
1.51 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.76 |
1.24 |
1.48 |
1.15 |
0.81 |
1.17 |
1.41 |
1.04 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.19 |
0.34 |
0.51 |
0.32 |
0.27 |
0.62 |
0.73 |
0.56 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.47 |
0.66 |
0.80 |
0.60 |
0.26 |
0.62 |
0.85 |
0.58 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.01 |
0.00 |
0.01 |
0.01 |
0.03 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.08 |
0.20 |
0.24 |
0.16 |
0.04 |
0.11 |
0.21 |
0.11 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.02 |
0.11 |
0.04 |
0.02 |
0.02 |
0.08 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.96 |
1.17 |
1.34 |
1.07 |
0.50 |
0.75 |
1.05 |
0.67 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.95 |
1.32 |
1.40 |
1.19 |
0.79 |
0.94 |
1.07 |
0.86 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.22 |
0.38 |
0.46 |
0.35 |
0.29 |
0.41 |
0.42 |
0.38 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.46 |
1.59 |
1.61 |
1.56 |
1.24 |
1.39 |
1.41 |
1.33 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.34 |
2.20 |
2.48 |
2.03 |
1.40 |
1.48 |
2.15 |
1.48 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.02 |
0.04 |
0.05 |
0.03 |
0.10 |
0.22 |
0.21 |
0.17 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.13 |
0.21 |
0.62 |
0.23 |
0.17 |
0.99 |
2.51 |
1.13 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
1.40 |
1.90 |
2.12 |
1.59 |
1.84 |
2.26 |
3.13 |
2.18 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
1.27 |
2.70 |
6.14 |
2.96 |
2.01 |
2.53 |
2.64 |
2.44 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.02 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.03 |
0.04 |
0.04 |
0.04 |
0.00 |
0.01 |
0.01 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.01 |
0.01 |
0.01 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.54 |
3.71 |
4.00 |
3.13 |
1.96 |
3.45 |
6.17 |
2.17 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.72 |
0.82 |
0.91 |
0.82 |
0.19 |
0.34 |
0.78 |
0.32 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.65 |
0.91 |
0.94 |
0.72 |
0.77 |
0.87 |
1.63 |
0.83 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.64 |
2.25 |
2.65 |
2.09 |
1.60 |
1.53 |
2.16 |
1.43 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Notes:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be
1.34-12.95 mg/L for dry season and 1.38-6.40 mg/L for wet season. The details
are presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 0.67-4.92 mg/L for dry season and 0.26-3.42 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30b Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project, Scenario
03c) at Construction Month 21
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.01 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
3.03 |
6.22 |
7.24 |
5.70 |
2.75 |
3.36 |
3.27 |
2.64 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR05a |
0.93 |
1.43 |
1.42 |
1.20 |
0.72 |
0.83 |
1.28 |
0.82 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.25 |
0.57 |
0.28 |
0.43 |
0.67 |
0.89 |
0.64 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
3.85 |
8.41 |
10.69 |
7.48 |
3.17 |
4.29 |
5.36 |
4.08 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.71 |
1.03 |
1.44 |
0.94 |
0.52 |
0.83 |
1.11 |
0.83 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.66 |
1.27 |
1.43 |
1.17 |
0.40 |
0.88 |
1.23 |
0.76 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.61 |
2.59 |
4.27 |
2.20 |
0.18 |
1.44 |
3.20 |
1.48 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.78 |
1.26 |
1.50 |
1.17 |
0.78 |
1.19 |
1.38 |
1.04 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.19 |
0.34 |
0.51 |
0.31 |
0.26 |
0.61 |
0.74 |
0.55 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.48 |
0.66 |
0.80 |
0.60 |
0.26 |
0.61 |
0.84 |
0.57 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.01 |
0.00 |
0.01 |
0.01 |
0.03 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.08 |
0.19 |
0.24 |
0.16 |
0.04 |
0.11 |
0.21 |
0.11 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.02 |
0.11 |
0.04 |
0.02 |
0.02 |
0.08 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.96 |
1.17 |
1.34 |
1.07 |
0.52 |
0.73 |
1.06 |
0.67 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.95 |
1.32 |
1.40 |
1.19 |
0.79 |
0.96 |
1.09 |
0.88 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.22 |
0.37 |
0.46 |
0.35 |
0.28 |
0.41 |
0.42 |
0.37 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.47 |
1.59 |
1.62 |
1.56 |
1.23 |
1.37 |
1.40 |
1.32 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.37 |
2.20 |
2.50 |
2.04 |
1.40 |
1.48 |
2.19 |
1.48 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.01 |
0.01 |
0.01 |
0.04 |
0.07 |
0.07 |
0.06 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.02 |
0.03 |
0.03 |
0.03 |
0.14 |
0.57 |
0.61 |
0.46 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
1.42 |
1.72 |
1.94 |
1.43 |
1.77 |
2.26 |
3.20 |
2.16 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
1.27 |
2.51 |
6.03 |
2.87 |
1.97 |
2.47 |
2.58 |
2.38 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.01 |
0.01 |
0.01 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.57 |
3.66 |
3.95 |
3.09 |
1.97 |
3.75 |
5.95 |
2.11 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.72 |
0.83 |
0.92 |
0.83 |
0.19 |
0.34 |
0.82 |
0.31 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.63 |
0.88 |
0.91 |
0.69 |
0.77 |
0.86 |
1.65 |
0.82 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.66 |
2.26 |
2.66 |
2.10 |
1.58 |
1.45 |
2.19 |
1.43 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 1.33-13.16
mg/L for dry season and 1.43-6.33 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 0.66-4.94 mg/L for dry season and 0.25-3.46 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30c Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project, Scenario
03c) at Construction Month 31
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.02 |
0.02 |
0.03 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.01 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
3.20 |
6.26 |
7.20 |
5.77 |
2.79 |
3.46 |
3.25 |
2.74 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR05a |
0.92 |
1.42 |
1.41 |
1.20 |
0.74 |
0.84 |
1.28 |
0.84 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.26 |
0.59 |
0.29 |
0.43 |
0.67 |
0.90 |
0.65 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
3.74 |
8.36 |
10.53 |
7.39 |
3.19 |
4.69 |
6.15 |
4.38 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.70 |
1.03 |
1.44 |
0.94 |
0.51 |
0.81 |
1.12 |
0.82 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.66 |
1.26 |
1.42 |
1.16 |
0.40 |
0.87 |
1.19 |
0.75 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
0.62 |
2.58 |
4.39 |
2.19 |
0.18 |
1.40 |
3.21 |
1.46 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.76 |
1.24 |
1.48 |
1.15 |
0.77 |
1.18 |
1.38 |
1.04 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.19 |
0.34 |
0.50 |
0.32 |
0.26 |
0.61 |
0.74 |
0.54 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.47 |
0.65 |
0.80 |
0.59 |
0.26 |
0.61 |
0.85 |
0.57 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.01 |
0.00 |
0.01 |
0.01 |
0.03 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.08 |
0.20 |
0.24 |
0.16 |
0.04 |
0.12 |
0.21 |
0.11 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.02 |
0.11 |
0.04 |
0.02 |
0.02 |
0.09 |
0.02 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
0.95 |
1.17 |
1.34 |
1.06 |
0.53 |
0.75 |
1.04 |
0.67 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
0.95 |
1.32 |
1.41 |
1.19 |
0.79 |
0.95 |
1.08 |
0.87 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.22 |
0.38 |
0.46 |
0.35 |
0.29 |
0.41 |
0.42 |
0.38 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.47 |
1.59 |
1.62 |
1.56 |
1.24 |
1.39 |
1.40 |
1.33 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.38 |
2.20 |
2.49 |
2.04 |
1.41 |
1.49 |
2.17 |
1.49 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.01 |
0.01 |
0.00 |
0.03 |
0.06 |
0.05 |
0.05 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.02 |
0.03 |
0.03 |
0.03 |
0.14 |
0.51 |
0.56 |
0.43 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
1.44 |
1.79 |
1.99 |
1.50 |
1.86 |
2.45 |
3.11 |
2.23 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR26 |
1.27 |
2.65 |
6.13 |
2.95 |
2.25 |
2.71 |
2.84 |
2.61 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.00 |
0.01 |
0.01 |
0.01 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.56 |
3.54 |
3.82 |
2.99 |
1.98 |
3.55 |
5.93 |
2.19 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
0.72 |
0.83 |
0.92 |
0.82 |
0.20 |
0.34 |
0.86 |
0.32 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
0.65 |
0.89 |
0.86 |
0.66 |
0.74 |
0.83 |
1.72 |
0.78 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.67 |
2.26 |
2.65 |
2.10 |
1.58 |
1.52 |
2.21 |
1.43 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be
1.36-12.94 mg/L for dry season and 1.42-6.40 mg/L for wet season. The details
are presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 0.66-4.93 mg/L for dry season and 0.25-3.44 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30d Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project,
Scenario 03c and 3RS) at Construction Month 15
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.45 |
0.57 |
0.61 |
0.55 |
0.00 |
0.02 |
0.04 |
0.02 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.25 |
0.32 |
0.35 |
0.31 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.01 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
1.99 |
2.59 |
2.70 |
2.29 |
1.78 |
2.34 |
2.29 |
1.90 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
1.04 |
1.45 |
1.51 |
1.25 |
0.67 |
1.06 |
1.61 |
0.99 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.22 |
0.54 |
0.24 |
0.54 |
0.85 |
1.09 |
0.81 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
2.08 |
6.04 |
7.76 |
5.41 |
2.17 |
4.20 |
4.65 |
3.67 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.80 |
1.14 |
1.53 |
1.03 |
0.57 |
0.93 |
1.32 |
0.94 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.73 |
1.47 |
1.62 |
1.32 |
0.33 |
0.92 |
1.37 |
0.82 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
1.34 |
3.80 |
5.45 |
3.09 |
0.59 |
2.48 |
6.08 |
2.92 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.86 |
1.35 |
1.65 |
1.25 |
0.88 |
1.52 |
1.69 |
1.31 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.20 |
0.40 |
0.53 |
0.32 |
0.34 |
0.80 |
0.94 |
0.72 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.53 |
0.70 |
0.85 |
0.65 |
0.28 |
0.77 |
1.07 |
0.74 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.04 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.09 |
0.24 |
0.28 |
0.18 |
0.07 |
0.13 |
0.25 |
0.12 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.03 |
0.13 |
0.05 |
0.03 |
0.03 |
0.11 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
1.04 |
1.24 |
1.42 |
1.17 |
0.69 |
0.95 |
1.32 |
0.86 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
1.01 |
1.32 |
1.41 |
1.21 |
0.97 |
1.09 |
1.25 |
1.02 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.30 |
0.43 |
0.52 |
0.41 |
0.30 |
0.43 |
0.45 |
0.40 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.61 |
1.72 |
1.74 |
1.69 |
0.98 |
1.20 |
1.26 |
1.13 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.24 |
1.81 |
2.05 |
1.63 |
0.71 |
1.17 |
1.85 |
1.12 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.01 |
0.02 |
0.03 |
0.02 |
0.08 |
0.16 |
0.20 |
0.11 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.12 |
0.19 |
0.40 |
0.23 |
0.14 |
0.64 |
1.59 |
0.75 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
2.35 |
4.77 |
7.51 |
4.17 |
1.86 |
4.02 |
10.20 |
3.94 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
No |
WSR27 |
0.04 |
0.05 |
0.05 |
0.05 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.11 |
0.14 |
0.15 |
0.14 |
0.02 |
0.05 |
0.08 |
0.04 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
0.04 |
0.04 |
0.03 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.01 |
0.03 |
0.04 |
0.02 |
0.08 |
0.18 |
0.37 |
0.19 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.06 |
0.10 |
0.10 |
0.09 |
0.18 |
0.38 |
0.68 |
0.31 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.07 |
0.10 |
0.11 |
0.09 |
0.24 |
0.28 |
0.26 |
0.27 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.01 |
0.01 |
0.01 |
0.03 |
0.05 |
0.04 |
0.04 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.06 |
0.06 |
0.06 |
0.06 |
0.06 |
0.07 |
0.06 |
0.06 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.25 |
2.29 |
3.44 |
2.09 |
2.05 |
2.35 |
4.02 |
2.07 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
2.39 |
2.81 |
3.19 |
2.81 |
1.09 |
2.66 |
3.44 |
2.23 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
2.02 |
2.52 |
2.49 |
2.40 |
1.39 |
1.66 |
1.87 |
1.65 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.13 |
1.92 |
2.18 |
1.76 |
0.89 |
1.18 |
1.75 |
1.08 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.75-13.15
mg/L for dry season and 0.96-7.08 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 2.03-4.86 mg/L for dry season and 1.26-3.02- mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30e Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project,
Scenario 03c and 3RS) at Construction Month 21
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.02 |
0.03 |
0.03 |
0.03 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.01 |
0.02 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
1.94 |
2.54 |
2.64 |
2.25 |
1.84 |
2.24 |
2.12 |
1.83 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
1.03 |
1.47 |
1.51 |
1.26 |
0.68 |
1.11 |
1.58 |
0.98 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.22 |
0.54 |
0.24 |
0.53 |
0.85 |
1.08 |
0.81 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
2.09 |
6.02 |
7.78 |
5.40 |
2.29 |
4.04 |
4.85 |
3.73 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.79 |
1.13 |
1.56 |
1.02 |
0.58 |
0.91 |
1.29 |
0.92 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.74 |
1.49 |
1.65 |
1.34 |
0.35 |
0.92 |
1.40 |
0.81 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
1.33 |
3.74 |
5.38 |
3.05 |
0.54 |
2.51 |
6.28 |
2.93 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.85 |
1.34 |
1.65 |
1.24 |
0.86 |
1.48 |
1.69 |
1.29 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.21 |
0.40 |
0.54 |
0.33 |
0.32 |
0.78 |
0.92 |
0.70 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.54 |
0.71 |
0.86 |
0.66 |
0.27 |
0.75 |
1.05 |
0.71 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.04 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.09 |
0.23 |
0.28 |
0.18 |
0.06 |
0.14 |
0.25 |
0.13 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.03 |
0.13 |
0.05 |
0.03 |
0.03 |
0.11 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
1.05 |
1.24 |
1.42 |
1.18 |
0.69 |
0.94 |
1.32 |
0.85 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
1.01 |
1.32 |
1.40 |
1.21 |
0.97 |
1.09 |
1.25 |
1.02 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.30 |
0.43 |
0.52 |
0.41 |
0.30 |
0.44 |
0.45 |
0.40 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.60 |
1.71 |
1.73 |
1.68 |
0.98 |
1.21 |
1.27 |
1.13 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.25 |
1.81 |
2.07 |
1.63 |
0.70 |
1.16 |
1.85 |
1.12 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
0.06 |
0.10 |
0.05 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.01 |
0.01 |
0.01 |
0.01 |
0.10 |
0.39 |
0.44 |
0.32 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
2.36 |
4.77 |
7.46 |
4.16 |
1.91 |
3.95 |
10.79 |
3.71 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
No |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.01 |
0.01 |
0.00 |
0.02 |
0.04 |
0.06 |
0.03 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.03 |
0.03 |
0.03 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.01 |
0.03 |
0.03 |
0.02 |
0.09 |
0.18 |
0.36 |
0.18 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.06 |
0.10 |
0.10 |
0.09 |
0.18 |
0.38 |
0.66 |
0.31 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.07 |
0.10 |
0.11 |
0.09 |
0.24 |
0.29 |
0.27 |
0.27 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.01 |
0.01 |
0.01 |
0.03 |
0.05 |
0.04 |
0.04 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.05 |
0.06 |
0.06 |
0.06 |
0.06 |
0.07 |
0.06 |
0.06 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.24 |
2.33 |
3.41 |
2.10 |
2.14 |
2.41 |
4.63 |
2.11 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
2.35 |
2.76 |
3.14 |
2.76 |
0.99 |
2.69 |
3.51 |
2.27 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
2.05 |
2.57 |
2.58 |
2.45 |
1.37 |
1.65 |
1.87 |
1.64 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.13 |
1.93 |
2.17 |
1.77 |
0.84 |
1.20 |
1.72 |
1.07 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.72-12.98
mg/L for dry season and 1.00-7.08 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 1.99-4.88 mg/L for dry season and 1.26-2.97 mg/L for wet
season. The details are presented in Appendix 5.4b.
Table
5.30f Predicted
Maximum Suspended Solids (mg/L) Elevations (Mitigated and Concurrent Project,
Scenario 03c and 3RS) at Construction Month 31
WSR
|
Modeling Result
|
Suspended Solids Criteria (mg/L)
|
|
||||||||||||||
Dry Season
|
Wet Season
|
Dry Season
|
Wet Season
|
Compliance to Suspended Solids
Criteria (mg/L)
|
|||||||||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
||
WSR01 |
0.03 |
0.03 |
0.04 |
0.03 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR02 |
0.01 |
0.02 |
0.02 |
0.02 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR03 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR04 |
1.95 |
2.53 |
2.66 |
2.24 |
1.77 |
2.17 |
2.14 |
1.79 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR05a |
1.03 |
1.46 |
1.50 |
1.26 |
0.67 |
1.05 |
1.62 |
1.00 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR05b |
0.22 |
0.22 |
0.54 |
0.24 |
0.54 |
0.86 |
1.09 |
0.82 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR06 |
2.09 |
6.09 |
7.78 |
5.43 |
2.42 |
3.96 |
5.45 |
3.80 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
No |
WSR07 |
0.79 |
1.13 |
1.55 |
1.02 |
0.58 |
0.90 |
1.32 |
0.92 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR08 |
0.73 |
1.47 |
1.62 |
1.32 |
0.33 |
0.92 |
1.31 |
0.83 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR10 |
1.33 |
3.89 |
5.41 |
3.16 |
0.52 |
2.47 |
6.25 |
2.88 |
4.2 |
5.7 |
9.7 |
6.2 |
2.9 |
4 |
10.9 |
6.1 |
Yes |
WSR11 |
0.86 |
1.35 |
1.65 |
1.25 |
0.87 |
1.50 |
1.69 |
1.30 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
700 |
Yes |
WSR12 |
0.20 |
0.40 |
0.53 |
0.32 |
0.32 |
0.80 |
0.93 |
0.71 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
Yes |
WSR13 |
0.53 |
0.71 |
0.87 |
0.66 |
0.28 |
0.77 |
1.05 |
0.71 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.04 |
0.01 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR15 |
0.09 |
0.23 |
0.28 |
0.18 |
0.06 |
0.14 |
0.25 |
0.13 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR16 |
0.01 |
0.03 |
0.13 |
0.05 |
0.03 |
0.03 |
0.11 |
0.03 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR17 |
1.05 |
1.23 |
1.41 |
1.18 |
0.69 |
0.91 |
1.34 |
0.84 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR18 |
1.00 |
1.31 |
1.40 |
1.20 |
0.97 |
1.09 |
1.26 |
1.02 |
3.3 |
4.8 |
5.1 |
4.4 |
2 |
3.3 |
5.8 |
3.6 |
Yes |
WSR19 |
0.30 |
0.43 |
0.52 |
0.41 |
0.30 |
0.44 |
0.45 |
0.40 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR20 |
1.60 |
1.71 |
1.73 |
1.68 |
0.98 |
1.22 |
1.26 |
1.14 |
2.4 |
3.3 |
5.2 |
3.7 |
1.7 |
2.7 |
5.1 |
2.9 |
Yes |
WSR21 |
1.25 |
1.81 |
2.07 |
1.64 |
0.74 |
1.18 |
1.86 |
1.13 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR22a |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
0.05 |
0.08 |
0.04 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR22c |
0.01 |
0.01 |
0.01 |
0.01 |
0.09 |
0.37 |
0.41 |
0.30 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
WSR25 |
2.37 |
4.84 |
7.77 |
4.26 |
1.90 |
3.99 |
11.34 |
3.67 |
3.3 |
3.9 |
6.3 |
4.3 |
2.4 |
3 |
5.1 |
3.5 |
No |
WSR27 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR28 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.03 |
0.05 |
0.02 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR29 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.03 |
0.02 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR30 |
0.01 |
0.02 |
0.03 |
0.02 |
0.09 |
0.18 |
0.37 |
0.18 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR31 |
0.06 |
0.10 |
0.10 |
0.08 |
0.18 |
0.38 |
0.69 |
0.32 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
0.02 |
0.01 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR33 |
0.07 |
0.10 |
0.10 |
0.09 |
0.24 |
0.30 |
0.27 |
0.28 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR34 |
0.00 |
0.01 |
0.01 |
0.01 |
0.03 |
0.05 |
0.04 |
0.04 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR35 |
0.05 |
0.06 |
0.06 |
0.06 |
0.06 |
0.07 |
0.06 |
0.06 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR41 |
2.28 |
2.23 |
3.27 |
1.99 |
2.15 |
2.37 |
4.68 |
2.12 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR42 |
2.39 |
2.80 |
3.18 |
2.80 |
1.12 |
2.64 |
3.46 |
2.24 |
6.9 |
7.9 |
12.7 |
9 |
3 |
4.9 |
9.4 |
5.6 |
Yes |
WSR44 |
2.03 |
2.56 |
2.53 |
2.42 |
1.39 |
1.70 |
1.88 |
1.67 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
10 |
Yes |
WSR45 |
1.13 |
1.93 |
2.18 |
1.76 |
0.88 |
1.24 |
1.76 |
1.10 |
2.8 |
3 |
5.5 |
3.9 |
2.4 |
2.6 |
2.9 |
2.5 |
Yes |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged;
[2] For
the observation points around Brothers Islands Marine Park (M1-M5), the
predicted maximum suspended solids elevations in depth averaged would be 0.74-13.19
mg/L for dry season and 1.17-7.12 mg/L for wet season. The details are
presented in Appendix 5.4b.
[3] For
the observation points around Sha Chau
and Lung Kwu Chau Marine
Park (M6-M10), the predicted maximum suspended solids elevations in depth
averaged would be 2.00-4.85 mg/L for dry season and 1.28-3.17 mg/L for wet
season. The details are presented in Appendix 5.4b.
Sedimentation Rate
5.5.7.12 The predicted maximum daily sedimentation rates at all the sensitive receivers are summarised in Table 5.31a-c. The predicted maximum daily sedimentation rates at the affected WSRs with 3RS are summarised in Table 5.31d. According to the modelling results, it is clear that the predicted daily sedimentation rates due to construction under the unmitigated scenario (Scenario 03a), mitigated scenario (Scenario 03b), cumulative impact scenario (Scenario 03c) and sensitivity scenario with 3RS at all WSRs are well within the criterion of 200 g/m2/day. At observation point M2, which would be nearest to ESC CMPs, the predicted maximum daily sedimentation rates in the cumulative impact scenario (Scenario 03c) and sensitivity scenario with 3RS are 112 and 107 g/m2/day respectively, which are within the criterion of 200 g/m2/day. Hence, adverse water quality impact due to sedimentation is not anticipated.
Table
5.31a Predicted Maximum Sedimentation Rates (Unmitigated, Scenario 03a)
Water Sensitive Receivers
|
Predicted
Maximum Sedimentation Rates (g/m2/day)
|
|||||
Dry
Season
|
Wet
Season
|
|||||
M15
|
M21
|
M31
|
M15
|
M21
|
M31
|
|
WSR01 |
6.48 |
0.26 |
0.41 |
0.24 |
0.01 |
0.01 |
WSR02 |
3.56 |
0.13 |
0.20 |
0.10 |
0.00 |
0.00 |
WSR03 |
0.11 |
0.00 |
0.00 |
0.02 |
0.00 |
0.00 |
WSR04 |
0.00 |
0.00 |
0.20 |
0.48 |
0.65 |
6.70 |
WSR05a |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.06 |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR06 |
0.00 |
0.01 |
0.03 |
0.12 |
0.23 |
4.95 |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR10 |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
0.08 |
WSR11 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
0.08 |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR17 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
0.02 |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR20 |
0.00 |
0.00 |
0.01 |
0.02 |
0.01 |
0.04 |
WSR21 |
0.02 |
0.02 |
0.11 |
0.19 |
0.09 |
1.08 |
WSR22a |
0.27 |
0.02 |
0.05 |
0.80 |
0.02 |
0.09 |
WSR22b |
0.02 |
0.00 |
0.00 |
0.01 |
0.00 |
0.01 |
WSR22c |
7.43 |
0.07 |
0.07 |
32.35 |
0.78 |
2.10 |
WSR25 |
0.01 |
0.09 |
1.06 |
0.12 |
0.26 |
3.88 |
WSR26 |
0.01 |
0.06 |
0.74 |
0.13 |
0.23 |
2.92 |
WSR27 |
0.27 |
0.01 |
0.01 |
0.06 |
0.00 |
0.00 |
WSR28 |
0.67 |
0.01 |
0.02 |
0.10 |
0.00 |
0.00 |
WSR29 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR41 |
0.01 |
0.11 |
1.33 |
0.18 |
0.38 |
5.31 |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR44 |
0.01 |
0.02 |
1.18 |
0.07 |
0.06 |
0.78 |
WSR45 |
0.04 |
0.04 |
0.22 |
0.16 |
0.10 |
1.10 |
[1] For the observation points around Brothers
Islands Marine Park (M1-M5), the predicted maximum sedimentation rates would be
0.00-10.98 mg/L for dry season and 0.02-27.14 mg/L for wet season. The details
are presented in Appendix 5.4b.
[2] For the observation points around Sha Chau and Lung Kwu Chau Marine Park (M6-M10),
the predicted maximum suspended solids elevations in depth averaged would be
0.00-0.07 mg/L for dry season and 0.00-0.32 mg/L for wet season. The details
are presented in Appendix 5.4b.
Table 5.31b Predicted Maximum Sedimentation Rates (Mitigated, Scenario 03b)
Water Sensitive Receivers
|
Predicted
Maximum Sedimentation Rates (g/m2/day)
|
|||||
Dry
Season
|
Wet
Season
|
|||||
M15
|
M21
|
M31
|
M15
|
M21
|
M31
|
|
WSR01 |
3.53 |
0.14 |
0.23 |
0.13 |
0.00 |
0.00 |
WSR02 |
1.97 |
0.07 |
0.11 |
0.05 |
0.00 |
0.00 |
WSR03 |
0.06 |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
WSR04 |
0.00 |
0.00 |
0.11 |
0.25 |
0.35 |
3.70 |
WSR05a |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.03 |
WSR05b |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
WSR06 |
0.00 |
0.00 |
0.01 |
0.07 |
0.13 |
2.64 |
WSR07 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
WSR08 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
WSR10 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.04 |
WSR11 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
0.04 |
WSR12 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
WSR13 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.02 |
WSR14 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR15 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR16 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR17 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR18 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR19 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR20 |
0.00 |
0.00 |
0.00 |
0.01 |
0.00 |
0.02 |
WSR21 |
0.01 |
0.01 |
0.06 |
0.10 |
0.05 |
0.59 |
WSR22a |
0.15 |
0.01 |
0.02 |
0.43 |
0.01 |
0.05 |
WSR22b |
0.01 |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
WSR22c |
4.10 |
0.04 |
0.04 |
17.79 |
0.43 |
1.17 |
WSR25 |
0.00 |
0.05 |
0.60 |
0.06 |
0.13 |
2.03 |
WSR26 |
0.00 |
0.03 |
0.40 |
0.07 |
0.12 |
1.60 |
WSR27 |
0.15 |
0.00 |
0.01 |
0.03 |
0.00 |
0.00 |
WSR28 |
0.37 |
0.01 |
0.01 |
0.06 |
0.00 |
0.00 |
WSR29 |
0.01 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR30 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR31 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR32 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR33 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR34 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR35 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
WSR41 |
0.01 |
0.06 |
0.73 |
0.10 |
0.21 |
2.97 |
WSR42 |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
0.01 |
WSR44 |
0.00 |
0.01 |
0.65 |
0.04 |
0.03 |
0.43 |
WSR45 |
0.03 |
0.02 |
0.12 |
0.09 |
0.06 |
0.61 |
[1] For the observation points around Brothers
Islands Marine Park (M1-M5), the predicted maximum sedimentation rates would be
0.00-5.96 mg/L for dry season and 0.01-15.00 mg/L for wet season. The details
are presented in Appendix 5.4b.
[2] For the observation points around Sha Chau and Lung Kwu Chau Marine Park (M6-M10),
the predicted maximum suspended solids elevations in depth averaged would be
0.00-0.04 mg/L for dry season and 0.00-0.18 mg/L for wet season. The details
are presented in Appendix 5.4b.
Table 5.31c Predicted Maximum Sedimentation Rates (Mitigated and Concurrent Project,
Scenario 03c)
Water Sensitive Receivers
|
Predicted
Maximum Sedimentation Rates (g/m2/day)
|
|||||
Dry
Season
|
Wet
Season
|
|||||
M15
|
M21
|
M31
|
M15
|
M21
|
M31
|
|
WSR01 |
3.53 |
0.14 |
0.23 |
0.13 |
0.00 |
0.00 |
WSR02 |
1.96 |
0.07 |
0.11 |
0.05 |
0.00 |
0.00 |
WSR03 |
0.06 |
0.00 |
0.00 |
0.01 |
0.00 |
0.00 |
WSR04 |
55.44 |
55.07 |
55.73 |
20.75 |
20.33 |
20.03 |
WSR05a |
12.05 |
12.07 |
12.01 |
10.11 |
10.02 |
9.87 |
WSR05b |
5.00 |
4.75 |
4.95 |
7.36 |
7.26 |
7.42 |
WSR06 |
77.84 |
79.92 |
79.31 |
45.25 |
41.96 |
45.64 |
WSR07 |
9.69 |
9.73 |
9.63 |
7.19 |
7.27 |
7.27 |
WSR08 |
11.12 |
11.22 |
11.16 |
10.28 |
10.49 |
10.09 |
WSR10 |
34.24 |
33.50 |
34.30 |
22.78 |
22.49 |
21.41 |
WSR11 |
12.71 |
12.87 |
12.71 |
11.96 |
11.74 |
11.71 |
WSR12 |
4.13 |
4.13 |
4.13 |
6.16 |
6.10 |
6.09 |
WSR13 |
6.12 |
6.14 |
6.05 |
5.16 |
5.10 |
5.32 |
WSR14 |
0.06 |
0.06 |
0.06 |
0.23 |
0.21 |
0.22 |
WSR15 |
1.88 |
1.86 |
1.88 |
1.69 |
1.68 |
1.68 |
WSR16 |
0.92 |
0.92 |
0.91 |
0.71 |
0.70 |
0.73 |
WSR17 |
10.48 |
10.60 |
10.50 |
8.37 |
8.57 |
8.61 |
WSR18 |
6.94 |
6.83 |
6.92 |
5.65 |
5.71 |
5.63 |
WSR19 |
3.26 |
3.25 |
3.29 |
3.44 |
3.42 |
3.44 |
WSR20 |
12.42 |
12.30 |
12.32 |
11.89 |
11.90 |
11.89 |
WSR21 |
13.48 |
13.86 |
13.73 |
13.71 |
13.64 |
13.58 |
WSR22a |
0.41 |
0.08 |
0.06 |
1.79 |
0.61 |
0.44 |
WSR22b |
0.01 |
0.00 |
0.00 |
0.08 |
0.03 |
0.02 |
WSR22c |
4.10 |
0.29 |
0.25 |
17.22 |
5.18 |
4.76 |
WSR25 |
18.26 |
16.44 |
17.10 |
24.71 |
25.31 |
24.52 |
WSR26 |
51.08 |
50.14 |
50.85 |
21.51 |
21.23 |
22.93 |
WSR27 |
0.15 |
0.00 |
0.01 |
0.03 |
0.00 |
0.00 |
WSR28 |
0.37 |
0.01 |
0.01 |
0.06 |
0.01 |
0.01 |
WSR29 |
0.01 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
WSR30 |
0.02 |
0.02 |
0.01 |
0.07 |
0.08 |
0.08 |
WSR31 |
0.05 |
0.04 |
0.05 |
0.19 |
0.19 |
0.19 |
WSR32 |
0.00 |
0.00 |
0.00 |
0.01 |
0.01 |
0.01 |
WSR33 |
0.02 |
0.02 |
0.02 |
0.06 |
0.06 |
0.06 |
WSR34 |
0.00 |
0.00 |
0.00 |
0.02 |
0.02 |
0.02 |
WSR35 |
0.02 |
0.02 |
0.02 |
0.03 |
0.03 |
0.03 |
WSR41 |
21.50 |
20.14 |
21.27 |
51.53 |
49.69 |
49.43 |
WSR42 |
5.62 |
5.40 |
5.56 |
6.00 |
6.32 |
6.59 |
WSR44 |
7.64 |
7.40 |
6.96 |
8.48 |
9.05 |
8.78 |
WSR45 |
13.16 |
13.29 |
13.26 |
14.11 |
13.93 |
14.17 |
[1] For the observation points around Brothers
Islands Marine Park (M1-M5), the predicted maximum sedimentation rates would be
11.94-111.74 mg/L for dry season and 13.16-73.91 mg/L for wet season. The
details are presented in Appendix 5.4b.
[2] For the observation points around Sha Chau and Lung Kwu Chau Marine Park (M6-M10),
the predicted maximum suspended solids elevations in depth averaged would be
4.76-51.93 mg/L for dry season and 1.99-44.46 mg/L for wet season. The details
are presented in Appendix 5.4b.
Table 5.31d Predicted Maximum Sedimentation Rates (Mitigated and Concurrent Project,
Scenario 03c and 3RS)
Water Sensitive Receivers
|
Predicted
Maximum Sedimentation Rates (g/m2/day)
|
|||||
Dry
Season
|
Wet
Season
|
|||||
M15
|
M21
|
M31
|
M15
|
M21
|
M31
|
|
WSR01 |
5.17 |
0.25 |
0.31 |
0.35 |
0.01 |
0.01 |
WSR02 |
2.99 |
0.13 |
0.16 |
0.19 |
0.01 |
0.01 |
WSR03 |
0.15 |
0.00 |
0.00 |
0.03 |
0.00 |
0.00 |
WSR04 |
17.49 |
17.24 |
17.84 |
12.24 |
12.83 |
12.96 |
WSR05a |
12.82 |
12.82 |
12.76 |
13.15 |
12.77 |
13.16 |
WSR05b |
4.53 |
4.58 |
4.53 |
9.06 |
8.97 |
9.17 |
WSR06 |
51.36 |
54.69 |
50.30 |
34.72 |
38.11 |
39.05 |
WSR07 |
10.60 |
10.57 |
10.53 |
7.65 |
7.53 |
7.44 |
WSR08 |
12.93 |
13.13 |
12.97 |
11.30 |
11.47 |
10.70 |
WSR10 |
35.12 |
34.94 |
34.54 |
34.50 |
34.83 |
33.85 |
WSR11 |
13.98 |
13.96 |
14.01 |
13.93 |
13.76 |
13.89 |
WSR12 |
4.38 |
4.46 |
4.43 |
7.70 |
7.59 |
7.67 |
WSR13 |
6.29 |
6.28 |
6.25 |
6.33 |
6.25 |
6.35 |
WSR14 |
0.04 |
0.04 |
0.04 |
0.37 |
0.37 |
0.36 |
WSR15 |
2.23 |
2.21 |
2.20 |
2.13 |
2.03 |
2.14 |
WSR16 |
1.08 |
1.10 |
1.09 |
0.90 |
0.90 |
0.92 |
WSR17 |
11.63 |
11.69 |
11.63 |
10.31 |
10.77 |
10.83 |
WSR18 |
7.11 |
7.04 |
6.97 |
7.38 |
7.25 |
7.25 |
WSR19 |
3.60 |
3.60 |
3.59 |
3.58 |
3.59 |
3.61 |
WSR20 |
13.25 |
13.06 |
13.09 |
10.70 |
10.77 |
10.71 |
WSR21 |
12.46 |
12.68 |
12.70 |
12.88 |
12.46 |
12.58 |
WSR22a |
0.22 |
0.03 |
0.03 |
1.68 |
0.88 |
0.72 |
WSR22b |
0.01 |
0.00 |
0.00 |
0.06 |
0.02 |
0.01 |
WSR22c |
2.85 |
0.09 |
0.08 |
11.11 |
3.66 |
3.41 |
WSR25 |
48.88 |
50.04 |
50.12 |
85.90 |
92.87 |
96.07 |
WSR27 |
0.41 |
0.01 |
0.02 |
0.04 |
0.00 |
0.00 |
WSR28 |
1.28 |
0.06 |
0.04 |
0.55 |
0.47 |
0.39 |
WSR29 |
0.03 |
0.00 |
0.00 |
0.37 |
0.29 |
0.22 |
WSR30 |
0.28 |
0.25 |
0.22 |
2.56 |
2.65 |
2.75 |
WSR31 |
0.83 |
0.83 |
0.81 |
5.00 |
4.88 |
5.05 |
WSR32 |
0.02 |
0.02 |
0.01 |
0.13 |
0.13 |
0.14 |
WSR33 |
0.59 |
0.59 |
0.57 |
2.05 |
2.00 |
2.04 |
WSR34 |
0.05 |
0.04 |
0.04 |
0.35 |
0.35 |
0.34 |
WSR35 |
0.46 |
0.42 |
0.44 |
0.43 |
0.43 |
0.43 |
WSR41 |
22.85 |
24.41 |
22.34 |
33.90 |
39.09 |
38.68 |
WSR42 |
13.93 |
14.90 |
14.19 |
20.92 |
21.60 |
22.34 |
WSR44 |
21.17 |
21.19 |
21.09 |
12.94 |
12.42 |
13.27 |
WSR45 |
13.28 |
13.19 |
13.27 |
12.36 |
11.89 |
11.90 |
[1] For the observation points around Brothers
Islands Marine Park (M1-M5), the predicted maximum sedimentation rates would be
9.01-107.4 mg/L for dry season and 8.94-80.27 mg/L for wet season. The details
are presented in Appendix 5.4b.
[2] For the observation points around Sha Chau and Lung Kwu Chau Marine Park (M6-M10),
the predicted maximum suspended solids elevations in depth averaged would be
13.38-48.99 mg/L for dry season and 19.98-43.58 mg/L for wet season. The
details are presented in Appendix 5.4b.
Dissolved
Oxygen Depletion
5.5.7.13
The degree of oxygen depletion exerted by a
sediment plume is a function of the sediment oxygen demand of the sediment, the
concentration in the water column and the rate of oxygen replenishment. In this assessment, the impact of
sediment oxygen demand on dissolved oxygen concentrations has been calculated
based on the following equation:
DODep = C
* COD * K * 0.001
where,
DODep = Dissolved Oxygen depletion
(mg/l)
C =
SS concentration (kg/m3)
COD =
Chemical Oxygen Demand
K =
Daily oxygen uptake factor (set at 1.0 for worse case estimate)
5.5.7.14
COD was assumed as 11,600 mg/kg, which is the COD
measured in the sediment samples at EPD routine monitoring station NS2 in Year
2014. The above equation does not allow for re-aeration which would tend to
reduce any impact of the suspended sediment on the water column DO
concentrations. Hence, the analysis
is on the conservative side so as not to underestimate the extent of DO
depletion. Furthermore, it should
be noted that, for sediment in suspension to exert any oxygen demand on the
water column will take time and at that time, the sediment will be transported
and mixed with oxygenated water. As
a result, the oxygen demand and the impact on dissolved oxygen concentrations
will diminish as the suspended sediment concentrations decrease.
5.5.7.15
Oxygen depletion is not instantaneous. Previous
studies have assumed that the impact of suspended sediment on dissolved oxygen
will depend on tidally averaged suspended sediment concentrations. In this
study, increase in suspended sediment has been used as the basis for the
calculation in order to identify the hypothetical worst case. As such, the daily uptake factor, K, in
the equation above is set to 1.0 as that in the HZMB EIAs studies (AEIAR-145/2009, AEIAR-144/2009). This represents
instantaneous oxidation of the sediment oxygen demand. It also represents the worst
case to ensure oxidation rates are not underestimated. The resulting calculated
dissolved oxygen deficit, therefore, is expected to be much larger than that would
be experienced in reality.
5.5.7.16 The oxygen depletion exerted by the max SS elevation from month 15, 21 and 31 is calculated in Table 5.32a-c below. The oxygen depletion exerted by the max SS elevation from month 15, 21 and 31 at the affected WSRs under sensitivity scenario with 3RS are summarised in Table 5.32d. It is anticipated that the oxygen depletion at representative WSR will be less than the detection limit of 0.1mg/L. Thus the DO depletion at all sensitive receivers will be insignificant.
Table 5.32a Predicted Maximum Oxygen Depletion (mg/L) for Scenario
03a
WSR
|
Dry Season
|
Wet Season
|
||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
|
WSR01 |
6.42E-03 |
8.13E-03 |
8.71E-03 |
7.87E-03 |
8.42E-05 |
1.41E-04 |
3.32E-04 |
1.63E-04 |
WSR02 |
3.39E-03 |
4.42E-03 |
4.79E-03 |
4.26E-03 |
3.71E-05 |
4.48E-05 |
1.34E-04 |
4.69E-05 |
WSR03 |
1.17E-04 |
1.43E-04 |
1.49E-04 |
1.38E-04 |
9.00E-06 |
1.03E-05 |
2.64E-05 |
1.43E-05 |
WSR04 |
6.70E-05 |
1.13E-04 |
2.73E-04 |
1.14E-04 |
5.92E-04 |
4.58E-03 |
9.61E-03 |
4.85E-03 |
WSR05a |
4.91E-06 |
6.98E-06 |
8.02E-06 |
6.71E-06 |
5.15E-05 |
6.35E-05 |
9.10E-05 |
6.36E-05 |
WSR05b |
4.73E-07 |
1.07E-06 |
3.32E-06 |
1.51E-06 |
2.38E-05 |
3.29E-05 |
3.99E-05 |
3.19E-05 |
WSR06 |
5.11E-05 |
5.81E-05 |
6.38E-05 |
5.78E-05 |
2.90E-04 |
9.17E-04 |
6.66E-03 |
2.00E-03 |
WSR07 |
1.77E-06 |
2.86E-06 |
3.40E-06 |
2.57E-06 |
1.54E-05 |
3.83E-05 |
5.52E-05 |
3.72E-05 |
WSR08 |
1.72E-06 |
3.61E-06 |
4.28E-06 |
3.37E-06 |
1.16E-05 |
3.27E-05 |
4.92E-05 |
2.89E-05 |
WSR10 |
1.11E-06 |
8.26E-06 |
1.14E-05 |
7.08E-06 |
4.52E-06 |
6.84E-05 |
1.31E-04 |
6.45E-05 |
WSR11 |
4.46E-06 |
7.86E-06 |
1.00E-05 |
7.19E-06 |
4.23E-05 |
8.74E-05 |
1.04E-04 |
7.62E-05 |
WSR12 |
5.15E-07 |
1.76E-06 |
2.65E-06 |
1.68E-06 |
1.83E-05 |
3.87E-05 |
4.58E-05 |
3.52E-05 |
WSR13 |
1.16E-06 |
2.47E-06 |
3.27E-06 |
2.10E-06 |
2.04E-05 |
4.74E-05 |
5.56E-05 |
4.34E-05 |
WSR14 |
4.29E-09 |
8.24E-09 |
1.44E-08 |
8.79E-09 |
1.02E-07 |
1.04E-07 |
1.82E-06 |
4.84E-07 |
WSR15 |
1.63E-07 |
4.34E-07 |
7.11E-07 |
3.91E-07 |
2.33E-06 |
8.60E-06 |
1.60E-05 |
7.98E-06 |
WSR16 |
3.40E-08 |
6.78E-08 |
4.18E-07 |
1.39E-07 |
3.60E-07 |
4.03E-07 |
6.57E-06 |
1.47E-06 |
WSR17 |
3.66E-06 |
4.43E-06 |
4.97E-06 |
4.06E-06 |
2.31E-05 |
2.68E-05 |
4.11E-05 |
2.70E-05 |
WSR18 |
4.60E-06 |
6.29E-06 |
6.51E-06 |
5.23E-06 |
2.64E-05 |
2.59E-05 |
2.71E-05 |
2.34E-05 |
WSR19 |
1.13E-06 |
1.98E-06 |
2.46E-06 |
1.85E-06 |
8.82E-06 |
1.24E-05 |
1.26E-05 |
1.16E-05 |
WSR20 |
8.16E-06 |
8.69E-06 |
8.77E-06 |
8.41E-06 |
7.92E-05 |
7.83E-05 |
5.65E-05 |
6.96E-05 |
WSR21 |
1.36E-04 |
2.36E-04 |
2.91E-04 |
2.14E-04 |
1.60E-03 |
1.88E-03 |
2.10E-03 |
1.86E-03 |
WSR22a |
1.90E-04 |
2.89E-04 |
3.70E-04 |
2.86E-04 |
6.98E-05 |
2.50E-04 |
1.10E-03 |
3.91E-04 |
WSR22b |
1.13E-05 |
1.97E-05 |
2.95E-05 |
2.00E-05 |
2.47E-06 |
5.17E-06 |
1.29E-05 |
6.33E-06 |
WSR22c |
2.79E-03 |
4.46E-03 |
1.31E-02 |
4.79E-03 |
3.29E-03 |
2.06E-02 |
5.23E-02 |
2.35E-02 |
WSR25 |
2.49E-04 |
1.43E-03 |
1.95E-03 |
1.11E-03 |
2.91E-03 |
5.50E-03 |
7.59E-03 |
4.28E-03 |
WSR26 |
3.34E-04 |
7.39E-04 |
1.11E-03 |
6.67E-04 |
2.76E-03 |
4.97E-03 |
5.58E-03 |
4.29E-03 |
WSR27 |
3.23E-04 |
3.73E-04 |
3.64E-04 |
3.59E-04 |
1.11E-05 |
2.15E-05 |
8.53E-05 |
3.31E-05 |
WSR28 |
7.06E-04 |
8.55E-04 |
9.03E-04 |
8.32E-04 |
6.13E-05 |
1.14E-04 |
1.43E-04 |
1.05E-04 |
WSR29 |
1.20E-05 |
1.39E-05 |
1.40E-05 |
1.33E-05 |
3.98E-07 |
1.44E-06 |
2.48E-06 |
1.35E-06 |
WSR30 |
1.73E-06 |
2.06E-06 |
2.10E-06 |
1.99E-06 |
4.85E-07 |
9.52E-07 |
1.34E-06 |
7.92E-07 |
WSR31 |
1.44E-08 |
2.43E-08 |
2.07E-08 |
2.01E-08 |
6.35E-08 |
2.78E-07 |
5.63E-07 |
2.97E-07 |
WSR32 |
2.00E-10 |
1.03E-09 |
2.62E-09 |
1.26E-09 |
3.95E-09 |
1.29E-08 |
3.08E-08 |
1.25E-08 |
WSR33 |
1.49E-08 |
2.28E-08 |
2.91E-08 |
1.81E-08 |
1.79E-07 |
2.44E-07 |
2.25E-07 |
1.96E-07 |
WSR34 |
1.74E-09 |
3.38E-09 |
3.24E-09 |
2.87E-09 |
3.32E-08 |
5.05E-08 |
6.59E-08 |
4.00E-08 |
WSR35 |
3.52E-08 |
4.97E-08 |
5.68E-08 |
4.24E-08 |
6.42E-08 |
7.62E-08 |
8.31E-08 |
6.10E-08 |
WSR41 |
4.04E-04 |
1.62E-03 |
3.05E-03 |
1.53E-03 |
1.12E-03 |
3.79E-03 |
1.18E-02 |
4.65E-03 |
WSR42 |
1.21E-06 |
1.51E-06 |
1.94E-06 |
1.50E-06 |
5.52E-06 |
9.74E-06 |
1.62E-05 |
8.89E-06 |
WSR44 |
6.15E-04 |
1.10E-03 |
1.63E-03 |
1.10E-03 |
1.69E-04 |
2.71E-04 |
1.14E-03 |
3.84E-04 |
WSR45 |
2.50E-04 |
5.82E-04 |
1.02E-03 |
5.57E-04 |
1.67E-03 |
2.63E-03 |
3.15E-03 |
2.46E-03 |
Note:
(1) S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged.
Table
5.32b Predicted Maximum Oxygen Depletion (mg/L) for Scenario 03b
WSR
|
Dry Season
|
Wet Season
|
||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
|
WSR01 |
3.53E-03 |
4.47E-03 |
4.78E-03 |
4.32E-03 |
4.62E-05 |
7.77E-05 |
1.83E-04 |
8.94E-05 |
WSR02 |
1.86E-03 |
2.43E-03 |
2.64E-03 |
2.35E-03 |
2.04E-05 |
2.47E-05 |
7.37E-05 |
2.58E-05 |
WSR03 |
6.48E-05 |
7.87E-05 |
8.18E-05 |
7.61E-05 |
4.96E-06 |
5.65E-06 |
1.46E-05 |
7.89E-06 |
WSR04 |
3.74E-05 |
6.22E-05 |
1.51E-04 |
6.29E-05 |
3.25E-04 |
2.52E-03 |
5.23E-03 |
2.66E-03 |
WSR05a |
2.74E-06 |
3.89E-06 |
4.46E-06 |
3.74E-06 |
2.84E-05 |
3.46E-05 |
4.87E-05 |
3.51E-05 |
WSR05b |
2.67E-07 |
5.94E-07 |
1.85E-06 |
8.42E-07 |
1.30E-05 |
1.85E-05 |
2.27E-05 |
1.80E-05 |
WSR06 |
2.86E-05 |
3.22E-05 |
3.53E-05 |
3.21E-05 |
1.61E-04 |
5.14E-04 |
3.59E-03 |
1.08E-03 |
WSR07 |
9.65E-07 |
1.59E-06 |
1.94E-06 |
1.42E-06 |
8.56E-06 |
2.15E-05 |
3.16E-05 |
2.09E-05 |
WSR08 |
9.54E-07 |
2.00E-06 |
2.38E-06 |
1.87E-06 |
6.43E-06 |
1.81E-05 |
2.71E-05 |
1.58E-05 |
WSR10 |
6.18E-07 |
4.57E-06 |
6.30E-06 |
3.91E-06 |
2.52E-06 |
3.81E-05 |
7.29E-05 |
3.59E-05 |
WSR11 |
2.48E-06 |
4.38E-06 |
5.59E-06 |
4.01E-06 |
2.31E-05 |
4.84E-05 |
5.68E-05 |
4.22E-05 |
WSR12 |
2.84E-07 |
9.80E-07 |
1.48E-06 |
9.38E-07 |
9.92E-06 |
2.11E-05 |
2.51E-05 |
1.92E-05 |
WSR13 |
6.35E-07 |
1.38E-06 |
1.81E-06 |
1.17E-06 |
1.14E-05 |
2.60E-05 |
3.05E-05 |
2.38E-05 |
WSR14 |
2.40E-09 |
4.61E-09 |
7.98E-09 |
4.92E-09 |
5.54E-08 |
5.66E-08 |
9.88E-07 |
2.64E-07 |
WSR15 |
8.98E-08 |
2.41E-07 |
3.92E-07 |
2.15E-07 |
1.29E-06 |
4.66E-06 |
8.80E-06 |
4.34E-06 |
WSR16 |
1.87E-08 |
3.76E-08 |
2.33E-07 |
7.74E-08 |
1.98E-07 |
2.22E-07 |
3.55E-06 |
8.13E-07 |
WSR17 |
2.04E-06 |
2.44E-06 |
2.73E-06 |
2.26E-06 |
1.26E-05 |
1.48E-05 |
2.25E-05 |
1.47E-05 |
WSR18 |
2.56E-06 |
3.46E-06 |
3.66E-06 |
2.92E-06 |
1.45E-05 |
1.42E-05 |
1.50E-05 |
1.28E-05 |
WSR19 |
6.35E-07 |
1.11E-06 |
1.39E-06 |
1.04E-06 |
4.82E-06 |
6.79E-06 |
6.88E-06 |
6.34E-06 |
WSR20 |
4.53E-06 |
4.78E-06 |
4.83E-06 |
4.62E-06 |
4.31E-05 |
4.26E-05 |
3.08E-05 |
3.79E-05 |
WSR21 |
7.47E-05 |
1.29E-04 |
1.59E-04 |
1.17E-04 |
8.85E-04 |
1.04E-03 |
1.15E-03 |
1.03E-03 |
WSR22a |
1.06E-04 |
1.60E-04 |
2.05E-04 |
1.59E-04 |
3.84E-05 |
1.39E-04 |
6.05E-04 |
2.15E-04 |
WSR22b |
6.20E-06 |
1.08E-05 |
1.62E-05 |
1.09E-05 |
1.36E-06 |
2.84E-06 |
7.07E-06 |
3.47E-06 |
WSR22c |
1.53E-03 |
2.45E-03 |
7.21E-03 |
2.64E-03 |
1.81E-03 |
1.14E-02 |
2.87E-02 |
1.29E-02 |
WSR25 |
1.37E-04 |
7.84E-04 |
1.07E-03 |
6.09E-04 |
1.60E-03 |
3.02E-03 |
4.21E-03 |
2.37E-03 |
WSR26 |
1.85E-04 |
4.04E-04 |
6.05E-04 |
3.65E-04 |
1.50E-03 |
2.73E-03 |
3.09E-03 |
2.36E-03 |
WSR27 |
1.79E-04 |
2.06E-04 |
2.01E-04 |
1.98E-04 |
6.15E-06 |
1.19E-05 |
4.72E-05 |
1.83E-05 |
WSR28 |
3.91E-04 |
4.73E-04 |
5.00E-04 |
4.61E-04 |
3.37E-05 |
6.28E-05 |
8.00E-05 |
5.84E-05 |
WSR29 |
6.64E-06 |
7.60E-06 |
7.68E-06 |
7.31E-06 |
2.18E-07 |
7.89E-07 |
1.39E-06 |
7.40E-07 |
WSR30 |
9.67E-07 |
1.15E-06 |
1.17E-06 |
1.11E-06 |
2.16E-07 |
5.14E-07 |
7.24E-07 |
4.28E-07 |
WSR31 |
7.93E-09 |
1.33E-08 |
1.13E-08 |
1.10E-08 |
3.40E-08 |
1.51E-07 |
3.07E-07 |
1.61E-07 |
WSR32 |
1.47E-10 |
6.40E-10 |
1.85E-09 |
9.01E-10 |
2.11E-09 |
8.30E-09 |
1.66E-08 |
6.77E-09 |
WSR33 |
1.03E-08 |
1.15E-08 |
1.36E-08 |
9.45E-09 |
9.76E-08 |
1.31E-07 |
1.20E-07 |
1.06E-07 |
WSR34 |
6.18E-10 |
1.28E-09 |
2.04E-09 |
9.09E-10 |
1.72E-08 |
2.72E-08 |
3.58E-08 |
2.09E-08 |
WSR35 |
1.57E-08 |
3.14E-08 |
3.43E-08 |
2.81E-08 |
3.49E-08 |
4.15E-08 |
5.13E-08 |
3.32E-08 |
WSR41 |
2.24E-04 |
8.90E-04 |
1.68E-03 |
8.43E-04 |
6.22E-04 |
2.09E-03 |
6.42E-03 |
2.58E-03 |
WSR42 |
6.67E-07 |
8.32E-07 |
1.08E-06 |
8.24E-07 |
3.00E-06 |
5.43E-06 |
8.89E-06 |
4.95E-06 |
WSR44 |
3.41E-04 |
6.09E-04 |
8.99E-04 |
6.12E-04 |
9.28E-05 |
1.47E-04 |
6.32E-04 |
2.12E-04 |
WSR45 |
1.37E-04 |
3.19E-04 |
5.60E-04 |
3.05E-04 |
9.16E-04 |
1.46E-03 |
1.73E-03 |
1.36E-03 |
Note:
(1) S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged.
Table 5.32c Predicted Maximum Oxygen Depletion (mg/L) for Scenario
03c
WSR
|
Dry Season
|
Wet Season
|
||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
|
WSR01 |
3.53E-03 |
4.47E-03 |
4.79E-03 |
4.33E-03 |
4.64E-05 |
7.77E-05 |
1.83E-04 |
8.95E-05 |
WSR02 |
1.86E-03 |
2.43E-03 |
2.63E-03 |
2.34E-03 |
2.04E-05 |
2.47E-05 |
7.35E-05 |
2.58E-05 |
WSR03 |
6.46E-05 |
7.85E-05 |
8.14E-05 |
7.59E-05 |
4.95E-06 |
5.64E-06 |
1.45E-05 |
7.87E-06 |
WSR04 |
3.71E-02 |
7.31E-02 |
8.40E-02 |
6.69E-02 |
3.23E-02 |
4.11E-02 |
4.15E-02 |
3.27E-02 |
WSR05a |
1.08E-02 |
1.66E-02 |
1.65E-02 |
1.40E-02 |
8.56E-03 |
9.75E-03 |
1.50E-02 |
9.69E-03 |
WSR05b |
2.58E-03 |
3.02E-03 |
6.97E-03 |
3.36E-03 |
5.10E-03 |
7.90E-03 |
1.04E-02 |
7.56E-03 |
WSR06 |
4.47E-02 |
9.76E-02 |
1.24E-01 |
8.67E-02 |
3.71E-02 |
5.44E-02 |
7.14E-02 |
5.08E-02 |
WSR07 |
8.24E-03 |
1.20E-02 |
1.68E-02 |
1.09E-02 |
6.05E-03 |
9.68E-03 |
1.30E-02 |
9.64E-03 |
WSR08 |
7.68E-03 |
1.48E-02 |
1.66E-02 |
1.35E-02 |
4.80E-03 |
1.05E-02 |
1.42E-02 |
8.91E-03 |
WSR10 |
7.13E-03 |
3.01E-02 |
5.09E-02 |
2.56E-02 |
2.08E-03 |
1.67E-02 |
3.88E-02 |
1.75E-02 |
WSR11 |
9.07E-03 |
1.46E-02 |
1.74E-02 |
1.36E-02 |
9.38E-03 |
1.38E-02 |
1.64E-02 |
1.20E-02 |
WSR12 |
2.23E-03 |
3.99E-03 |
5.91E-03 |
3.70E-03 |
3.16E-03 |
7.24E-03 |
8.58E-03 |
6.46E-03 |
WSR13 |
5.54E-03 |
7.66E-03 |
9.25E-03 |
6.91E-03 |
3.07E-03 |
7.21E-03 |
9.85E-03 |
6.69E-03 |
WSR14 |
2.15E-05 |
4.11E-05 |
8.08E-05 |
4.43E-05 |
6.57E-05 |
6.75E-05 |
3.14E-04 |
8.22E-05 |
WSR15 |
8.99E-04 |
2.29E-03 |
2.79E-03 |
1.88E-03 |
5.16E-04 |
1.34E-03 |
2.42E-03 |
1.25E-03 |
WSR16 |
1.22E-04 |
2.13E-04 |
1.27E-03 |
4.30E-04 |
2.70E-04 |
2.40E-04 |
1.00E-03 |
2.33E-04 |
WSR17 |
1.12E-02 |
1.36E-02 |
1.55E-02 |
1.24E-02 |
6.12E-03 |
8.73E-03 |
1.23E-02 |
7.80E-03 |
WSR18 |
1.10E-02 |
1.54E-02 |
1.63E-02 |
1.38E-02 |
9.21E-03 |
1.11E-02 |
1.26E-02 |
1.02E-02 |
WSR19 |
2.55E-03 |
4.36E-03 |
5.39E-03 |
4.07E-03 |
3.38E-03 |
4.81E-03 |
4.88E-03 |
4.40E-03 |
WSR20 |
1.70E-02 |
1.85E-02 |
1.88E-02 |
1.81E-02 |
1.44E-02 |
1.61E-02 |
1.63E-02 |
1.54E-02 |
WSR21 |
1.60E-02 |
2.56E-02 |
2.90E-02 |
2.37E-02 |
1.63E-02 |
1.73E-02 |
2.54E-02 |
1.73E-02 |
WSR22a |
2.13E-04 |
4.23E-04 |
5.51E-04 |
3.93E-04 |
1.19E-03 |
2.55E-03 |
2.41E-03 |
1.92E-03 |
WSR22b |
6.37E-06 |
1.12E-05 |
1.75E-05 |
1.15E-05 |
1.32E-04 |
1.36E-04 |
1.03E-04 |
1.24E-04 |
WSR22c |
1.54E-03 |
2.45E-03 |
7.21E-03 |
2.64E-03 |
2.01E-03 |
1.15E-02 |
2.91E-02 |
1.31E-02 |
WSR25 |
1.67E-02 |
2.21E-02 |
2.46E-02 |
1.84E-02 |
2.16E-02 |
2.84E-02 |
3.71E-02 |
2.59E-02 |
WSR26 |
1.48E-02 |
3.13E-02 |
7.12E-02 |
3.44E-02 |
2.61E-02 |
3.14E-02 |
3.30E-02 |
3.03E-02 |
WSR27 |
1.78E-04 |
2.05E-04 |
2.00E-04 |
1.98E-04 |
6.16E-06 |
1.19E-05 |
4.69E-05 |
1.83E-05 |
WSR28 |
3.87E-04 |
4.69E-04 |
4.94E-04 |
4.56E-04 |
3.35E-05 |
6.21E-05 |
7.85E-05 |
5.76E-05 |
WSR29 |
6.60E-06 |
7.56E-06 |
7.64E-06 |
7.27E-06 |
9.02E-06 |
1.82E-05 |
1.59E-05 |
1.45E-05 |
WSR30 |
4.15E-06 |
2.41E-05 |
3.23E-05 |
1.90E-05 |
2.46E-05 |
7.08E-05 |
1.15E-04 |
6.52E-05 |
WSR31 |
4.80E-05 |
8.64E-05 |
6.49E-05 |
6.70E-05 |
4.05E-05 |
1.66E-04 |
2.78E-04 |
1.60E-04 |
WSR32 |
2.13E-07 |
7.14E-07 |
9.79E-07 |
5.29E-07 |
2.20E-06 |
5.50E-06 |
1.37E-05 |
5.65E-06 |
WSR33 |
3.07E-05 |
5.10E-05 |
5.24E-05 |
4.42E-05 |
1.03E-04 |
1.29E-04 |
9.60E-05 |
1.10E-04 |
WSR34 |
1.82E-06 |
2.94E-06 |
2.70E-06 |
2.52E-06 |
1.76E-05 |
2.17E-05 |
2.91E-05 |
1.87E-05 |
WSR35 |
2.27E-05 |
2.48E-05 |
2.62E-05 |
2.47E-05 |
2.86E-05 |
3.29E-05 |
3.61E-05 |
2.64E-05 |
WSR41 |
2.98E-02 |
4.31E-02 |
4.64E-02 |
3.63E-02 |
2.30E-02 |
4.35E-02 |
7.15E-02 |
2.54E-02 |
WSR42 |
8.41E-03 |
9.63E-03 |
1.07E-02 |
9.61E-03 |
2.31E-03 |
3.97E-03 |
1.00E-02 |
3.69E-03 |
WSR44 |
7.55E-03 |
1.05E-02 |
1.09E-02 |
8.35E-03 |
8.93E-03 |
1.01E-02 |
1.99E-02 |
9.57E-03 |
WSR45 |
1.94E-02 |
2.62E-02 |
3.09E-02 |
2.43E-02 |
1.86E-02 |
1.77E-02 |
2.57E-02 |
1.66E-02 |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged.
Table 5.32d Predicted Maximum Oxygen Depletion (mg/L) for
Scenario 03c and 3RS
WSR
|
Dry Season
|
Wet Season
|
||||||
S
|
M
|
B
|
DA
|
S
|
M
|
B
|
DA
|
|
WSR01 |
5.21E-03 |
6.56E-03 |
7.03E-03 |
6.36E-03 |
3.74E-05 |
2.58E-04 |
4.65E-04 |
2.23E-04 |
WSR02 |
2.88E-03 |
3.73E-03 |
4.05E-03 |
3.61E-03 |
1.73E-05 |
8.77E-05 |
2.65E-04 |
1.13E-04 |
WSR03 |
1.52E-04 |
1.88E-04 |
1.96E-04 |
1.81E-04 |
3.90E-06 |
2.37E-05 |
4.28E-05 |
2.06E-05 |
WSR04 |
2.31E-02 |
3.01E-02 |
3.13E-02 |
2.66E-02 |
2.14E-02 |
2.71E-02 |
2.66E-02 |
2.20E-02 |
WSR05a |
1.21E-02 |
1.70E-02 |
1.75E-02 |
1.46E-02 |
7.91E-03 |
1.29E-02 |
1.88E-02 |
1.16E-02 |
WSR05b |
2.60E-03 |
2.59E-03 |
6.25E-03 |
2.82E-03 |
6.27E-03 |
1.00E-02 |
1.26E-02 |
9.49E-03 |
WSR06 |
2.42E-02 |
7.06E-02 |
9.03E-02 |
6.30E-02 |
2.81E-02 |
4.87E-02 |
6.33E-02 |
4.41E-02 |
WSR07 |
9.24E-03 |
1.32E-02 |
1.80E-02 |
1.19E-02 |
6.73E-03 |
1.08E-02 |
1.53E-02 |
1.08E-02 |
WSR08 |
8.59E-03 |
1.73E-02 |
1.91E-02 |
1.55E-02 |
4.08E-03 |
1.07E-02 |
1.63E-02 |
9.68E-03 |
WSR10 |
1.55E-02 |
4.51E-02 |
6.32E-02 |
3.66E-02 |
6.80E-03 |
2.91E-02 |
7.29E-02 |
3.40E-02 |
WSR11 |
9.98E-03 |
1.56E-02 |
1.92E-02 |
1.45E-02 |
1.02E-02 |
1.76E-02 |
1.96E-02 |
1.52E-02 |
WSR12 |
2.39E-03 |
4.67E-03 |
6.32E-03 |
3.82E-03 |
3.89E-03 |
9.26E-03 |
1.09E-02 |
8.30E-03 |
WSR13 |
6.30E-03 |
8.22E-03 |
1.01E-02 |
7.64E-03 |
3.25E-03 |
8.92E-03 |
1.24E-02 |
8.62E-03 |
WSR14 |
1.43E-05 |
2.67E-05 |
4.89E-05 |
2.65E-05 |
8.57E-05 |
9.41E-05 |
5.04E-04 |
1.41E-04 |
WSR15 |
1.10E-03 |
2.73E-03 |
3.26E-03 |
2.09E-03 |
7.57E-04 |
1.59E-03 |
2.89E-03 |
1.47E-03 |
WSR16 |
9.18E-05 |
2.98E-04 |
1.50E-03 |
5.61E-04 |
3.47E-04 |
3.34E-04 |
1.25E-03 |
3.90E-04 |
WSR17 |
1.22E-02 |
1.44E-02 |
1.65E-02 |
1.37E-02 |
8.03E-03 |
1.10E-02 |
1.55E-02 |
9.93E-03 |
WSR18 |
1.17E-02 |
1.53E-02 |
1.63E-02 |
1.40E-02 |
1.12E-02 |
1.26E-02 |
1.46E-02 |
1.18E-02 |
WSR19 |
3.48E-03 |
4.94E-03 |
6.07E-03 |
4.75E-03 |
3.44E-03 |
5.09E-03 |
5.27E-03 |
4.68E-03 |
WSR20 |
1.86E-02 |
1.99E-02 |
2.02E-02 |
1.96E-02 |
1.14E-02 |
1.42E-02 |
1.47E-02 |
1.32E-02 |
WSR21 |
1.45E-02 |
2.10E-02 |
2.41E-02 |
1.90E-02 |
8.61E-03 |
1.37E-02 |
2.16E-02 |
1.31E-02 |
WSR22a |
1.22E-04 |
2.04E-04 |
3.00E-04 |
2.04E-04 |
9.03E-04 |
1.85E-03 |
2.26E-03 |
1.33E-03 |
WSR22b |
6.69E-06 |
1.16E-05 |
1.69E-05 |
1.17E-05 |
9.89E-05 |
1.00E-04 |
7.83E-05 |
8.81E-05 |
WSR22c |
1.44E-03 |
2.24E-03 |
4.62E-03 |
2.65E-03 |
1.68E-03 |
7.44E-03 |
1.84E-02 |
8.69E-03 |
WSR25 |
2.74E-02 |
5.61E-02 |
9.02E-02 |
4.95E-02 |
2.21E-02 |
4.67E-02 |
1.32E-01 |
4.57E-02 |
WSR27 |
4.65E-04 |
5.53E-04 |
5.56E-04 |
5.33E-04 |
3.56E-06 |
1.50E-05 |
5.61E-05 |
2.13E-05 |
WSR28 |
1.32E-03 |
1.63E-03 |
1.74E-03 |
1.58E-03 |
2.34E-04 |
5.49E-04 |
8.74E-04 |
4.71E-04 |
WSR29 |
4.94E-05 |
4.93E-05 |
4.62E-05 |
4.69E-05 |
2.11E-04 |
4.42E-04 |
5.03E-04 |
3.88E-04 |
WSR30 |
1.02E-04 |
3.37E-04 |
4.10E-04 |
2.59E-04 |
1.00E-03 |
2.13E-03 |
4.28E-03 |
2.20E-03 |
WSR31 |
6.95E-04 |
1.19E-03 |
1.13E-03 |
1.01E-03 |
2.09E-03 |
4.43E-03 |
8.00E-03 |
3.66E-03 |
WSR32 |
4.39E-06 |
1.45E-05 |
2.08E-05 |
1.08E-05 |
5.37E-05 |
1.65E-04 |
1.91E-04 |
1.19E-04 |
WSR33 |
8.03E-04 |
1.17E-03 |
1.24E-03 |
1.03E-03 |
2.82E-03 |
3.43E-03 |
3.14E-03 |
3.22E-03 |
WSR34 |
4.31E-05 |
7.13E-05 |
6.46E-05 |
6.07E-05 |
3.51E-04 |
5.31E-04 |
5.04E-04 |
4.49E-04 |
WSR35 |
6.51E-04 |
7.13E-04 |
7.46E-04 |
7.06E-04 |
7.23E-04 |
7.97E-04 |
7.42E-04 |
7.47E-04 |
WSR41 |
2.65E-02 |
2.70E-02 |
3.99E-02 |
2.43E-02 |
2.49E-02 |
2.79E-02 |
5.43E-02 |
2.46E-02 |
WSR42 |
2.78E-02 |
3.26E-02 |
3.70E-02 |
3.25E-02 |
1.30E-02 |
3.12E-02 |
4.08E-02 |
2.63E-02 |
WSR44 |
2.37E-02 |
2.98E-02 |
2.99E-02 |
2.84E-02 |
1.61E-02 |
1.97E-02 |
2.18E-02 |
1.94E-02 |
WSR45 |
1.31E-02 |
2.24E-02 |
2.53E-02 |
2.05E-02 |
1.03E-02 |
1.44E-02 |
2.05E-02 |
1.27E-02 |
Note:
[1] S
¡V Surface Layer, M ¡V Middle Layer; B ¡V Bottom Layer; DA ¡V Depth Averaged.
Contaminant
Release from Pore Water
5.5.7.17 Although non-dredged reclamation method will be adopted, contaminant releases from pore water are still anticipated during filling. The pore water analysis results at the sampling locations are shown in Table 5.33a.
Table 5.33a Pore Water Test Results (for those sampling points with exceedance only)
Sampling Location |
Metalloid (£gg/L) |
TIN (mg/L) |
UIA (mg/L) |
As |
|||
Criteria / Baseline |
10 |
0.5 |
0.021 |
VB1 |
<10 |
1.97 |
0.08 |
VB2 |
<10 |
3.05 |
0.12 |
VB3 |
<10 |
2.79 |
0.11 |
VB4 |
<10 |
4.02 |
0.16 |
VB5 |
28 |
12.82 |
0.50 |
VB6 |
<10 |
2.50 |
0.10 |
VB7 |
<10 |
1.34 |
0.05 |
VB8 |
<10 |
1.16 |
0.04 |
VB9 |
<10 |
4.09 |
0.16 |
VB10 |
<10 |
5.21 |
0.20 |
VB11 |
<10 |
1.14 |
0.04 |
VB12 |
<10 |
1.11 |
0.04 |
VB13 |
<10 |
0.93 |
0.04 |
VB14 |
<10 |
1.34 |
0.05 |
VB15 |
<10 |
0.76 |
0.03 |
VB16 |
<10 |
1.06 |
0.04 |
VB17 |
<10 |
4.39 |
0.17 |
VB18 |
<10 |
3.57 |
0.14 |
VB19 |
<10 |
6.37 |
0.25 |
VB20 |
<10 |
1.11 |
0.04 |
VB21 |
<10 |
1.01 |
0.04 |
VB22 |
<10 |
1.01 |
0.04 |
VB23 |
<10 |
1.42 |
0.06 |
VB24 |
<10 |
0.86 |
0.03 |
VB25 |
<10 |
0.97 |
0.04 |
VB26 |
<10 |
0.93 |
0.04 |
VB27 |
<10 |
1.19 |
0.05 |
VB28 |
<10 |
1.36 |
0.05 |
Maximum |
28 |
12.82 |
0.50 |
5.5.7.18 The concentration of contaminants release from reclamation site to WSRs can be estimated by first order equation[4]: C(x) = q/(Dx£s£k0.5). Similar approach has been adopted in previous approved EIA studies[5],[6],[7],[8]. The dilution factor is estimated by assuming the radius of initial release as 10m. The total concentrations of contaminants and nutrients due to construction at the representative ecological WSRs are presented in Table 5.33b. The predicted As and UIA concentrations at these WSRs comply with the proposed criteria. Exceedance of TIN under WQO is observed, the contribution is due to high TIN level in background from Pearl River estuary. There is potential impact by the increase in non-compliance of TIN on the water sensitive receivers taking into account background level and nutrient enrichment effect and potential eutrophication/red tide of the water body due to the increase in TIN non-compliance. According to the literature[9], the nitrogen and phosphorus (N:P) ratio for red tide growth is 16:1. The growth of most red tide causative species in Hong Kong coastal water has been reported to be optimized at a low N:P (atomic) ratio of between 6 and 15[10].The N:P ratio from the baseline data at the representative WSRs range from 20:1-26:1. Phosphorus would be the limiting nutrient for the algae growth. The N:P ratio for the prediction of nutrient release from pore water range from 19:1-25:1. Red tide bloom is still limited by the phosphorus level. Thus, drastic increase of red tide occurrence at WSRs is not anticipated.
Table 5.33b Concentration of contaminants and nutrients at representative ecological
WSRs from Pore Water Test with background
WSR |
Corresponding EPD¡¦s Stations |
Baseline Condition |
Dilution factor |
Metalloid (£gg/L) |
TKN (mg/L) |
NH3-N (mg/L) |
TIN (mg/L) |
UIA (mg/L) |
Total P (mg/L) |
Ortho-P (mg/L) |
|||||
TKN (mg/L) |
NH3-N (mg/L) |
TIN (mg/L) |
UIA (mg/L) |
Total P (mg/L) |
Ortho-P (mg/L) |
As |
|||||||||
Criteria / Baseline |
- |
- |
0.5 |
0.021 |
- |
- |
25 |
- |
- |
0.5 |
0.021 |
- |
- |
||
WSR01 |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
285 |
0.10 |
0.34 |
0.152 |
0.63 |
0.005 |
0.05 |
0.029 |
WSR04 |
NM3 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
375 |
0.07 |
0.33 |
0.141 |
0.61 |
0.004 |
0.05 |
0.028 |
WSR06 |
NM3 |
0.29 |
0.108 |
0.63 |
0.003 |
0.04 |
0.025 |
279 |
0.10 |
0.34 |
0.154 |
0.68 |
0.005 |
0.05 |
0.031 |
WSR20 |
NM1 |
0.27 |
0.093 |
0.42 |
0.003 |
0.04 |
0.021 |
1167 |
0.02 |
0.28 |
0.104 |
0.43 |
0.003 |
0.04 |
0.022 |
WSR22c |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
196 |
0.14 |
0.37 |
0.172 |
0.65 |
0.006 |
0.05 |
0.032 |
WSR23 |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
331 |
0.08 |
0.34 |
0.146 |
0.62 |
0.005 |
0.05 |
0.028 |
WSR27 |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
329 |
0.09 |
0.34 |
0.146 |
0.62 |
0.005 |
0.05 |
0.028 |
WSR35 |
NM8 |
0.20 |
0.041 |
0.47 |
0.002 |
0.03 |
0.018 |
1870 |
0.01 |
0.21 |
0.048 |
0.48 |
0.002 |
0.03 |
0.019 |
WSR41 |
NM3 |
0.29 |
0.108 |
0.63 |
0.003 |
0.04 |
0.025 |
310 |
0.09 |
0.33 |
0.149 |
0.67 |
0.005 |
0.05 |
0.030 |
WSR42 |
NM5 |
0.31 |
0.122 |
0.71 |
0.004 |
0.05 |
0.028 |
1025 |
0.03 |
0.32 |
0.134 |
0.72 |
0.004 |
0.05 |
0.030 |
WSR44 |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
364 |
0.08 |
0.34 |
0.142 |
0.62 |
0.004 |
0.05 |
0.028 |
WSR45 |
NM2 |
0.30 |
0.107 |
0.58 |
0.003 |
0.04 |
0.023 |
469 |
0.06 |
0.33 |
0.134 |
0.61 |
0.004 |
0.04 |
0.027 |
5.5.8
Mitigation Measures
5.5.8.1
The above construction phase water quality assessment has been based on
the following design measures:
Design of Construction Method
¡P
Based on the latest design, the use of
non-dredged reclamation method is adopted.
¡P
All reclamation filling works should be
conducted within a leading seawall of 200m in advance of reclamation filling.
Good Management Practice in Construction Phase
5.5.8.2
Apart from the design measures, following good site management practices
shall be adopted for the filling works:
¡P
Water quality monitoring shall be implemented
to ensure effective control of water pollution and recommend additional
mitigation measures required;
¡P
The decent speed of grabs shall be controlled
to minimize the seabed impact and to reduce the volume of over-dredging
according to the assumed filling rate in water quality assessment in Appendix 5.4a;
¡P
A perimeter silt curtain shall be installed
during the entire reclamation periods;
¡P
Barges or hoppers shall not be filled to a
level which will cause overflow of materials or pollution of water during
loading or transportation;
¡P
Excess materials shall be cleaned from the
decks and exposed fittings of barges before the vessels are moved;
¡P
Plants should not be operated with leaking
pipes and any pipe leakages shall be repaired quickly;
¡P
Adequate freeboard shall be maintained on
barges to reduce the likelihood of decks being washed by wave action;
¡P
All vessels should be sized so that adequate
clearance is maintained between vessels and the seabed in all tide conditions,
to ensure that undue turbidity is not generated by turbulence from vessel
movement or propeller wash; and
¡P
The works shall not cause foam, oil, grease,
litter or other objectionable matter to be present in the water within and
adjacent to the works site.
¡P
Mitigation of the pollution generated from
general construction activities and sewage from workforce should follow the
good practice in Section 5.4.3.
Reuse of C&D materials
from the Land-based Works for Filling
5.5.8.3
As
discussed in the Waste Management implication in Section 7, all C&D materials arising from the
construction would be sorted on-site to recover the inert C&D materials.
All sorted inert C&D materials would be reused on-site for the reclamation
works. The recovered C&D materials for filling would be ensured no floating
or non-inert material by visual inspection, quality assurance, etc.
5.5.9
Residual Impacts
5.5.9.1
With the above design measures and good
practices, adverse residual water quality impact is not anticipated. No
residual adverse water quality impacts are anticipated.
5.6
Operational Phase Assessment
5.6.1
Identification of Pollution Sources/ Impacts
5.6.1.1
The key pollution sources/ impacts in operational phase includes:
¡P
Drainage Discharge and Runoff (including the
possible discharge into CA and CPA zonings, and some minor maintenance works)
¡P
Sewerage / Sewage Discharge
¡P
Change in Hydrodynamic Regime due to
Reclamation of Tung Chung East and Road P1 Extension
¡P
Emergency Discharge from Proposed Sewage Pumping Stations
¡P
Maintenance Dredging and Wastewater &
Sewage generated at Proposed Marina
¡P
Potential Polluted Runoff from Sports Ground
Facility
¡P
Maintenance Flushing for Freshwater and
Saltwater Reservoirs
5.6.2
Determination of
Assessment Year and Concurrent Projects
5.6.2.1
For this Tung Chung project, the first
population intake would be in Yr 2024 and the full
operation year would be in Yr 2030.
5.6.2.2
The potential concurrent projects for the operational
phase are summarized in Table 5.34. Major
projects currently under construction, including the TM-CLKL, HKBCF, HKLR and
HATS 2A are expected to be completed and in operation before or by end of Year 2016.
For the Expansion of HKIA 3RS, it is anticipated to be commissioned by 2023. LLP
is a currently planned project and it does not yet have a confirmed completion
date. For a conservative assessment, it is assumed to be in operation by Year 2026.
5.6.2.3
The Cumulative Environmental Impact Assessment
Study for the Three Potential Nearshore Reclamation
Sites in the Western Waters of Hong Kong (CEIA) include
the three proposed nearshore
reclamation sites in Siu Ho
Wan, Lung Kwu Tan and Sunny Bay. The
reclamation sites for both Sunny Bay and Lung Kwu Tan are considered as concurrent projects in this
study. For Sunny Bay, the reclamation layout in the EIA Study Brief
(ESB-272/2014) of Sunny Bay Development was adopted as the best available
information. Similarly for the Lung Kwu
Tan reclamation, the reclamation layout in CEIA was adopted. For the
Siu Ho Wan reclamation, however,
the project proponent of LLP has confirmed LLP should still be considered and
hence the LLP reclamation layout was adopted. Since the reclamation layout of
LLP is larger than the Siu Ho
Wan reclamation layout, the incorporation of LLP layout has represented the
worst case scenario. Although no implementation programme for Siu Ho Wan, Sunny Bay and Lung Kwu Tan, these reclamations are included in the operational
phase assessment.
5.6.2.4
For the projects Providing Sufficient Water
Depth at Kwai Tsing
Container Basin and its Approach Channel (KTCB) and MDF (South of The Brothers),
these projects will not involve land formation, but change in bathymetry. These
projects are anticipated to be completed by end 2016.
5.6.2.5
Yr
2030 was adopted as the operational phase assessment year in this study due to
full population intake. Water quality modellings for
the ¡¥with¡¦ and ¡¥without project¡¦ operational phase scenario were conducted.
Table 5.34 Summary of concurrent projects in operation
phase
Proposed/Planned Project in the Vicinity |
Tentative Implementation Programme |
Status & Consideration in This Study |
Hong Kong - Zhuhai -
Macao Bridge Hong Kong Boundary Crossing Facilities (HZMB HKBCF, being constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. Pollution loading from
BCF STW was included |
Tuen Mun
- Chek Lap Kok Link
(TM-CLKL, being constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. |
Hong Kong - Zhuhai -
Macao Bridge Hong Kong Link Road (HZMB HKLR, being constructed) |
Most of the marine
works to be completed by 2016 |
Land boundary was
included in this study. |
Harbour Area Treatment
Scheme (HATS) Stage 2A |
To be commissioned by
2016 |
Pollution loading was
included |
Expansion of Hong Kong
International Airport into a Three-Runway System (3RS) |
To be commissioned by
2023 |
Land boundary was
included in the study. Pollution loading from
3RS was included |
Possible Lantau Logistics Park |
Not available, assumed
to be in operation by Yr 2026 for modelling purpose |
Project proponent of
LLP has confirmed LLP should still be considered and hence the indicative LLP reclamation layout was adopted. For conservative
assessment, pollution load from the proposed STW in Siu
Ho Wan reclamation from CEIA was included. |
Sunny Bay Development |
Not available, assumed
to be in operation by Yr 2030 for modelling purpose |
The indicative reclamation layout in the EIA Study Brief
(ESB-272/2014) of Sunny Bay Development was included. According to CEIA
report, the pollution load from the proposed STW for Sunny Bay Development
was included. |
Lung Kwu Tan reclamation |
Not available, assumed
to be in operation by Yr 2030 for modelling purpose |
The indicative reclamation layout in CEIA was
included. According to CEIA, the
pollution load from the proposed STW for Lung Kwu
Tan reclamation was included. |
Providing Sufficient
Water Depth at Kwai Tsing
Container Basin and its Approach Channel (KTCB) |
To be commissioned by
2016 |
EP (EP-426/2011/A) was issued. The bathymetry was included in this study. |
Proposed New
Contaminated Mud Marine Disposal Facility at HKIA East/East Sha Chau Area (MDF) |
To be commissioned by
2016 |
EP (EP-427/2011/A and EP-312/2008/A) was issued. The bathymetry was included in this study. |
5.6.3
Drainage Discharge and Runoff
Tung Chung West
5.6.3.1
The existing
conditions for TCW development is partially rural area. With the development of
the Project, there would be an increase in the total paved area. Such change of
pavement will reduce the infiltration rate in the catchment, consequently
resulting in a higher flood risk as extra stormwater
runoff may be generated during rain events. The flood risks will be assessed
and addressed separately in the Drainage Impact Assessment Report under this
study. It is recommended that the capacities of road drainage system shall
cater for the runoff for 50 year-return-period rainstorm events.
5.6.3.2
In terms of water
quality impact, there would be additional pollution loading due to the increase
of runoff, which is known as non-point source pollutions during operational
phase. Substances such as vehicle dust, tyre scraps
and oils deposited and accumulated on the road surfaces will be washed into
nearby drainage system or watercourses during rainfall events. Some minor maintenance works such as landscaping work at the polder
or inside River Park will be conducted during the operations of stormwater attenuation and treatment ponds, SUDS, River
Park and associated drainage facilities. The minor maintenance works would be
well controlled and managed by the relevant government departments so that the treated
surface runoff to Tung Chung Stream in the maintenance
period would comply with the WPCO.
5.6.3.3
The TCW development is
located within the catchment of Tung Chung Stream, which covers North
and South Lantau Country Park with total area of over 1100 ha. The change
of effective catchment area due to TCW development is around 35.6 ha,
accounting for less than 3% of the whole catchment which could be considered
negligible.
5.6.3.4
Given the high
ecological value in river mouth of Tung Chung Stream, the effective catchment
area will remain as current conditions. Extra runoff due to the additional
paved surface from the project will be attenuated and treated by a set of
regional stormwater attenuation
and treatment ponds. All runoff from within
the catchment will run via the new drainage system, treated and then
temporarily stored in the stormwater
attenuation and treatment ponds (see RODP at Figure 2.2). A discharge spillway will be installed at each
pond. When the water level reaches the top of the discharge spillway runoff
will be diverted back into Tung Chung Stream. To provide flood protection,
temporarily stored runoff within each pond will discharge slowly back to the
Stream. Thus the stormwater attenuation
and treatment ponds mitigate the extra
runoff by capturing and treating the first flush rainfall and attenuating large
flows. In the dry season, water quality deterioration due to stagnant situation in the stormwater attenuation and treatment ponds would be
avoided with the
implementation of suitable design measures, such as installation of subsurface
drainage to eliminate areas of standing water, implementation of maintenance
activities to remove any organic debris and to clear areas of stagnation etc., to
be determined during detailed design stage to ensure compliance with the WPCO
discharge standards. Therefore, change in hydrology and non-point source
loading regime at Tung Chung Stream catchment is not anticipated
5.6.3.5 The cumulative water quality impact due to non-point source loading without enhancement measures from TCW development was included in the hydrodynamic and water quality modelling as described in Section 5.3.4 and Section 5.3.5. Enhancement measures recommended include provision of stormwater attenuation and treatment ponds and dry weather flow interceptor at the existing villages as discussed in Section 5.6.8.
Tung
Chung East
5.6.3.6 TCE development will be a newly reclaimed land. Additional non-point source loading will be due to surface runoff from the reclamation land. In order to minimize the impact, silt traps and best management practices such as regular road cleaning shall be implemented. The cumulative water quality impact due to non-point source loading from TCE development are included in the hydrodynamic and water quality modelling as described in Section 5.3.4 and Section 5.3.5.
5.6.4
Sewerage / Sewage Discharge
5.6.4.1
During operational phase, sewage discharge
will be the major water pollution source. These include domestic sewage from
development for both TCE and TCW.
5.6.4.2
For individual commercial tenants, discharge
license under WPCO will be required individually and the discharge standards
according to TM-DSS to government foul sewers will be applied.
5.6.4.3
According to current design, all sewage
generated from the development will be diverted to Siu
Ho Wan STW. The sewage
treatment capacity reserved at the SHWSTW is adequate to cater for the
increased sewage arisen from this Project. Hence neither upgrading nor additional
mitigation measure for SHWSTW is required due to this project. However, fitting out works of SHWSTW will be carried out by DSD in a
timely manner to cater for the projected flows from
existing dischargers and committed projects within its catchment. Details of sewage and sewerage implication are presented in Section 6.
5.6.5
Emergency Discharge from Sewage Pumping Stations
5.6.5.1
Five new sewage pumping stations (SPSs) and
one upgraded SPS are proposed for this project. Their locations are shown in Figure 6.1-6.10. Two sewage
pumping stations, TCE East SPS and TCE West SPS, are located in southeast
corner and southwest development near MTR TCL for TCE. The Chung Man Road SPS (CMRSPS)
will be upgraded. Another three new SPSs, TCV East SPS, TCV North SPS and TCV
West SPS are proposed for Tung Chung West and Valley Development. The estimated
sewage flows for the proposed and upgraded sewage pumping stations are
presented in Table 5.35a -5.35c. The sewage pumping stations will
collect the sewage from the development and convey the sewage to the Siu Ho Wan Sewage Treatment
Works.
5.6.5.2
Given the sensitivity of Tung Chung Stream in
term of water quality and ecology and low flushing rate
in the semi-enclosed water body at the north of TCE, extensive
effort has been expedited to avoid the need for emergency discharges. In order to achieve this, the design of the SPSs
have been cautiously reviewed to include additional provisions including a)
100% standby pumping capacity plus spare pump with 50% pumping capacity, b)
twin rising mains; c) dual-feed power supply; d) emergency storage facilities up
to 6-hour ADWF capacity; e) emergency communication mechanism amongst relevant
government departments. (see Section 5.6.10.3 for more information). As discussed with DSD, with
these additional provisions, emergency discharge from TCV East SPS, TCV North
SPS, TCV West SPS and proposed upgrading of Chung Man Road SPS in TCW, TCE West
SPS and East SPS in TCE is not anticipated.
Table 5.35a Estimated Sewage Flows for
Proposed Sewage Pumping Stations to serve TCE Development
SPS |
Area
Served |
ADWF
(m3/day) |
Peaking
Factor |
Peak
Flow (l/s) |
TCE West SPS (Ultimate Stage) |
New development areas in the western portion of Tung Chung East and Area 56 |
12,891 |
3.00 |
448 |
TCE East SPS (Ultimate Stage) |
All new development areas in Tung
Chung East and Area 56 |
45,732 |
2.79 |
1,479 |
Table 5.35b Estimated
Sewage Flows for Upgraded Sewage Pumping Stations to serve TCW and Valley
Development
SPS |
Area Served |
ADWF (m3/day) |
Peaking
Factor |
Peak Flow (l/s) |
Upgraded CMRSPS |
New development areas
TCW-1, TCW-2, TCW-3, TCV-1, COM-1, COM-2, COM-3 and existing villages Ma Wan Chung and Wong Nai Uk |
3,119 |
3.50 |
126 |
Table 5.35c Estimated
Sewage Flows for Proposed Sewage Pumping Stations to serve TCW and Valley
Development
SPS |
Area Served |
ADWF
(m3/day) |
Peaking
Factor |
Peak Flow
(l/s) |
TCV West SPS |
New development areas TCV-3, TCV-4 and
existing villages Mok Ka,
Lam Che and Nim Yuen |
551 |
4.00 |
26 |
TCV North SPS |
New development area TCV-8
and existing village Ngau Au |
278 |
6.00 |
19 |
TCV East SPS |
All new development areas in TCW and existing
villages Mok Ka, Lam Che, Nim Yuen, Shek Mun Kap,
Ngau Au, Shek Lau Po, Ma
Wan Chung and Wong Nai Uk |
8,864 |
3.00 |
308 |
5.6.6
Water Quality for the Proposed Marina
Maintenance Dredging
5.6.6.1
Maintenance dredging will be carried out to
allow vessels to berth within the marina at low tide and to enhance
navigational safety. Maintenance dredging for the proposed marina usually to be
conducted for every 1-3 years. Derrick lighter with small grab capacity of
approximately 2 m3 will need to be employed due to the shallow water
depth and limited space inside the marina as well as the limitation on
anchorage length. Based on the area of marina of 42,000m2 and
sedimentation rate of 0.4mm per year predicted from the model (Drawing: Annual-Sed
in Appendix 5.7), the predicted
volume of dredged material would be relatively small as compared with the
construction phase impact. The maintenance dredging would be conducted in
scheduled manner with much slower rate within a semi-enclosed bay. Together
with the deployment of silt curtain, the dispersion of SS would be well controlled
and constrained locally. The SS impact for maintenance dredging to the WSRs is
not anticipated to be significant.
Wastewater
& Sewage
5.6.6.2
Subject to the detailed design by the future
operator, there may be boatyard, maintenance area and polder in the development
at the proposed marina. According to WPCO, discharge of the following matters
into coastal waters from any maintenance activities etc. are prohibited: PCB,
PAH, fumigant, pesticides, toxicant, chlorinated hydrocarbons, flammable or
toxic solvents, petroleum oil or tar, wastes liable to form scum, deposits or
discolouration, sludge or solid refuse of any kind under TM-DSS.
5.6.6.3
A sewerage system will be provided for the
boatyard and maintenance area in the proposed marina at the north of TCE. All
the sewage and wastewater generated from the operation of the maintenance
activities will be conveyed to Siu Ho Wan STW for treatment. The effluent will be treated to
meet the TM-DSS before discharging to the public sewerage. Hence, the operation
of the maintenance activities is not anticipated to cause unacceptable water
quality impact.
5.6.6.4
Besides, the current design has not allowed
any storm water outfalls to be discharged into the proposed marina. Similar to
the other marina, maintenance and clean-up would be conducted regularly by the
operator. Accumulation of pollutant e.g. fuel slick or other floating refuse in
the marina is not anticipated.
5.6.6.5
The proposed marina is a designated project
under O.2, Part I, Schedule 2 Designated Project requiring EPs. Hence, a
separate EIA study for proposed marina will be conducted by the future project
proponent. The EIA shall formulate a management plan to avoid adverse water
quality impact.
5.6.7
Potential Polluted Runoff from Sports Ground Facility
5.6.7.1
According to the TM-DSS, effluent discharge
into coastal water should meet the statutory standards. Prohibited substances
including PCB, PAH, fumigant, pesticide are not allowed
to discharge into coastal water. The design of the sports ground facility shall
implement all the necessary measures to ensure that the effluent discharged
into coastal water would meet the legislative requirement. For example, PCB,
PAH, fumigant, pesticides, toxicant, chlorinated hydrocarbons, flammable or
toxic solvents, petroleum oil or tar, wastes liable to form scum, deposits or
discolouration, sludge or solid refuse are prohibited to be discharged into
coastal water. The sports ground facility is a designated project under O.7,
Part I, Schedule 2 Designated Project requiring EPs. Hence, a separated EIA study
for sports ground facility will be conducted by its project proponent. The EIA shall
also formulate a management plan to avoid adverse water quality impact.
5.6.8
Maintenance Flushing for Freshwater and
Saltwater Reservoirs
5.6.8.1
As discussed in Section 2, the proposed
freshwater and saltwater reservoirs would be located near to the two existing
freshwater reservoirs up in the terrain west of Chek
Lap Kok New Village. Under normal situation, there is
no discharge from the service reservoir to the nearby water body. As part of
the necessary maintenance tasks, these reservoirs would need to be flushed for
cleaning but the frequency is not high. During flushing, the water would
be discharged via the washout pipes at a controlled manner. Similar
procedures are applicable for all services reservoirs. The current design
has allowed the flushing water to be discharged into the channelized section of
Wong Lung Hang which has limited ecological value. This discharged water
would follow the channelized section and reach the water body to the east of Sha Tsiu Tau, which is brackish
water with a varying salinity. Hence, given the amount of flushing water
to be discharged is not significant and the frequency of discharge is low, it
is considered that those flushing water would not cause significant changes to
the water quality in the vicinity of Sha Tsiu Tau.
Compliance with WPCO for discharge of wastewater will be ensured during
the operation of reservoir flushing.
5.6.9
Hydrodynamic and Water Quality Impact
Assessment
5.6.9.1
According to the current design, reclamation will
be required in TCE. It may affect the hydrodynamic regime in the area and cause
deterioration in the water quality. The design capacity of Siu
Ho Wan STW was checked and is able to cater for the
sewage generated by Tung Chung population.
Assessment Scenario
5.6.9.2
Hydrodynamic and water quality simulations for the following scenarios have
been conducted.
¡P
Do-nothing - Hydrodynamic and water quality (Scenario 01) simulation without the
project in place with ultimate coastline configuration)
¡P
Operation - Hydrodynamic and water quality (Scenario 02) simulation with the
project in place with ultimate coastline configuration)
Pollution
Load Inventory
5.6.9.3
The sewage generated from the project will be diverted to Siu Ho Wan STW. The design plant capacity of Siu
Ho Wan STW is 180,000m3/day. It is anticipated that the Siu Ho Wan STW is able to cater for the increased sewage generated from the project.
There is no additional sewage treatment works required under this project. However, fitting out works of
SHWSTW are to be completed by DSD in a timely manner to cater to the projected
flows within its catchment.
5.6.9.4
For the sake of modelling of operation phase, the effluent discharge from
major STWs, including Siu Ho Wan STW, Pillar Point
STW, Yuen Long STW, San Wai STW, Shatin
STW, Tai Po STW, Stonecutters Island STW, and Sham Tseng STW in the North
Western WCZ and Western Buffer WCZ. Victoria Harbour
WCZ and Deep Bay WCZ were updated according to the latest information on design
plant capacity and discharge license requirement for the pollution loads. The
pollution loading from major STWs were updated according to the design plant
capacity and discharge licenses. The loading from storm drain out of the project was adopted from the
Ultimate Year (Yr.2030) scenario under HATS Stage 2A EIA. The increase in storm drain loading due to the project is
calculated based on population intake of Tung Chung project. The methodology of calculation of storm drain loading is made
reference to HATS Stage 2A EIA Study.
5.6.9.5
The major pollution load due to the project will be the road runoff from
both TCE and TCW development. The non-point source
pollution loading due to Tung Chung project is presented in Appendix 5.5. The total loading of non-point source pollution due to the development
in terms of BOD5, TN and TP are 113 kg/day, 9 kg/day and 1 kg/day
respectively. The proposed SUDS was not taken into
account. These pollution loadings were incorporated into the water quality modelling in operational phase as a conservative scenario.
Hydrodynamic
Impact
5.6.9.6
The tidal flows simulations for Scenario H1 and H2 are presented in Appendix 5.6.
Channels
5.6.9.7
The accumulated flow, momentary flow and total
salinity flux at four major channels around the study site, namely, 1) Airport Channel, 2) BCF
South and 3) Airport North and 4) Ma Wan for both Scenario H1 and Scenario H2
are presented in Appendix 5.6. As shown in Appendix 5.6, there are insignificant changes in accumulated flow, momentary
flow and total salinity flux for Airport North and Ma Wan, as these two
channels are far away from the development. However, there are observable
changes for Airport Channel and BCF South due to the TCE reclamation. The
accumulated flow, momentary flow and total salinity flux are shown in Table 5.36a-c respectively.
Table 5.36a Comparison Results of
Accumulated Flow at Concerned Channels
Channels |
Seasons |
Accumulated Flow (m3) |
Difference (m3) |
|
Scenario H1 |
Scenario H2 |
|||
Airport Channel |
Dry |
-6.78E+07 |
-7.61E+07 |
-8.30E+06 |
Wet |
5.04E+07 |
3.31E+07 |
-1.73E+07 |
|
BCF South |
Dry |
-5.56E+07 |
-6.63E+07 |
-1.07E+07 |
Wet |
9.55E+07 |
6.64E+07 |
-2.91E+07 |
Table 5.36b Comparison Results of Momentary Flow at Concerned Channels
Channels |
Seasons |
Momentary Flow (m3/s) |
|
Scenario H1 |
Scenario H2 |
||
Airport Channel |
Dry |
-5.17E+02 ~ 4.82E+02 |
-5.00E+02 ~ 4.45E+02 |
Wet |
-4.39E+02 ~ 6.20E+02 |
-4.32E+02 ~ 5.59E+02 |
|
BCF South |
Dry |
-1.22E+03 ~ 1.33E+03 |
-1.12E+03 ~ 1.16E+03 |
Wet |
-1.14E+03 ~ 1.54E+03 |
-1.04E+03 ~ 1.34E+03 |
Table 5.36c Comparison results of total salinity flux at concerned channels
Channels |
Seasons |
Salinity Flux (kg/s) |
Difference
(kg/s) |
|
Scenario H1 |
Scenario H2 |
|||
Airport Channel |
Dry |
-2.01E+09 |
-2.25E+09 |
-2.40E+08 |
Wet |
8.17E+08 |
5.15E+08 |
-3.02E+08 |
|
BCF South |
Dry |
-1.64E+09 |
-1.96E+09 |
-3.20E+08 |
Wet |
1.76E+09 |
1.27E+09 |
-4.90E+08 |
5.6.9.8
The accumulated flow in Airport Channel
decreases in wet season and increases in dry season. Similarly,
the accumulated flow in BCF South decreases in wet season
and increases in dry season. The total salinity flux in Airport
Channel decreases in wet season and increases in dry season. Similarly,
the total salinity flux in BCF South decreases in wet season
and increases in dry season (Appendix 5.6). For
the predicted momentary flow across the Airport Channel and BCF
South, there is a very small decrease.
5.6.9.9
The change in accumulated flow
and total salinity flux does not however represent significant change
in flow discharge in absolute terms. The changes in momentary flow and
accumulated flow suggest that there may be change in flushing of the water
body. However, the water quality result does not show significant change in
this Airport Channel and BCF South despite the flow change (see Appendix 5.7 and Table
A.1-A.8). Therefore, it is not anticipated that the flow
change in Airport Channel and BCF South will affect the water quality in this
area.
5.6.9.10
Table
5.37 shows the maximum velocity at the key WSRs in the
vicinity. As shown in Table 5.37,
there is no significant change in maximum velocity at WSR 04, WSR25, WSR30 and
WSR31, which is far away from the development during dry and wet seasons. At
Tai Ho Wan Inlet (Inside) (WSR 22b), there is no
change in the flow as it is controlled mainly by tidal flow. There is slight
decrease in flow magnitude of WSRs near the development such as Tai Ho Wan Inlet (Outside) (WSR 22c), San Tau Beach SSSI (WSR
27) and Hau Hok Wan (WSR
29) in wet season. However, the change of water quality due to project is small
as shown in Table A.1-A.8 of Appendix 5.7. For example, the percentage change of
salinity, depth averaged DO and SS at San Tau Beach SSSI (WSR 27) in wet season
are -0.1%, 3.5%, 1.4% respectively and at Hau Hok Wan (WSR 29) are 0.6%, 2.9%, 1.1% respectively.
5.6.9.11
The flow directions near the Project Site
during dry and wet seasons at both flood and ebb tides are shown in Drawings VE-Dry, VF-Dry, VE-Wet, VF-Wet of Appendix 5.6, which
indicates that change of flow directions are insignificant with the
reclamation.
Table 5.37 Comparison Results of Maximum Flow
Velocity at Concerned WSRs
Observation Points |
Seasons |
Maximum Velocity (m/s) |
Difference (m/s) |
|
Scenario H1 |
Scenario H2 |
|||
Proposed Marine Park at
Brothers (WSR 04) |
Dry |
0.6287 |
0.6331 |
0.0044 |
Wet |
0.6819 |
0.6877 |
0.0058 |
|
Tai Ho Wan Inlet (Inside)
(WSR 22b) |
Dry |
0.053 |
0.052 |
-0.001 |
Wet |
0.053 |
0.052 |
-0.001 |
|
Tai Ho Wan Inlet
(Outside) (WSR 22c) |
Dry |
0.2404 |
0.2109 |
-0.0295 |
Wet |
0.2824 |
0.2092 |
-0.0732 |
|
Cooling water Intake at
HKIA (WSR25) |
Dry |
0.0834 |
0.0832 |
-0.0002 |
Wet |
0.0775 |
0.0772 |
-0.0003 |
|
San Tau Beach SSSI (WSR 27) |
Dry |
0.100 |
0.098 |
-0.002 |
Wet |
0.142 |
0.121 |
-0.021 |
|
Airport Channel (Hau Hok
Wan) (WSR 29) |
Dry |
0.1321 |
0.1282 |
-0.0039 |
Wet |
0.2013 |
0.1752 |
-0.0261 |
|
Sha Lo Wan (WSR30) |
Dry |
0.1314 |
0.1293 |
-0.0021 |
Wet |
0.2072 |
0.2085 |
0.0013 |
|
Sham Wat Wan (WSR 31) |
Dry |
0.0611 |
0.0617 |
0.0006 |
Wet |
0.1105 |
0.1101 |
-0.0004 |
Water Quality Impact
5.6.9.12
The overall water quality is affected by the
pollution loads. The major pollution sources would be the runoff from Pearl
River and loading from Siu Ho
Wan STW and Pillar Point STW, San Wai STW, etc..
5.6.9.13
Additional discharge from induced pavement
runoff is anticipated. These loadings are considered to be minor on comparing to
the loading from Pearl River and STW discharges. The simulations of water
quality impact under Scenario 01 and 02 have been conducted and the water
quality modeling results are presented in Appendix 5.7.
5.6.9.14
Table
A.1-A.8 in Appendix 5.7 summarizes the comparison results of the following
parameters, salinity, DO, BOD5, SS, TIN, unionized ammonia (UIA), and
E.coli at WSRs
under Scenario 01 and Scenario 02.
Salinity
5.6.9.15
Table
A.1-A.8 in Appendix 5.7 compare the
annual depth- averaged salinity between Scenario 01 and Scenario 02 at WSRs. The
contours of salinity are presented in Appendix 5.7. Results
indicate that the difference in salinity are within 10%
of the base case at the representative WSRs, which comply with WQO criteria.
Dissolved Oxygen (DO)
5.6.9.16
Table
A.1-A.8 in Appendix 5.7 compares the annual depth-averaged DO levels
and the near-bottom DO levels between Scenario 01 and Scenario 02 at WSRs. The contours of DO are presented in Appendix 5.7. Results
indicate that the depth-averaged DO levels and the near-bottom DO levels at representative
WSRs would be within the WQO (i.e. Depth averaged DO > 4mg/L and bottom DO
> 2mg/L).
Biological Oxygen Demand
(BOD5)
5.6.9.17 Table A.1-A.8 in Appendix 5.7 compare the annual depth averaged
BOD5 between Scenario 01 and Scenario 02 at WSRs. The contours of
BOD5 are presented in Appendix 5.7. The only applicable
BOD5 criteria is for seawater intakes. For
seawater intakes WSR 23 (LLP), WSR 43 (Tung Chung) and WSR44 (BCF), the results
indicate that the BOD5 levels are in compliance with WSD criteria.
For the other WSRs, there is no WQO for BOD5. Inside the proposed
marina, the maximum BOD5 level increases slightly from 2.0mg/L to
2.5mg/L in wet season. However, the depth-averaged DO level inside the proposed
marina is about 7mg/L which is still above and comply with the WQO of 4mg/L.
Inside the Tung Chung Bay, there is a slight increase in BOD, which is due to
the increase in runoff and paved area in Tung Chung West. For the sake of conservation, the
water quality assessment has not included the effectiveness of the SUDS
proposed as enhancement measure in Section 5.6.11. In the real situation,
the SUDS will help improve the
water quality before discharging to Tung Chung Stream due to increased surface runoff.
Suspended
Solids (SS)
5.6.9.18
Table
A.1-A.8 in Appendix 5.7 compare the
annual depth-averaged SS between Scenario 01 and Scenario 02 at WSRs. The
contours of SS are presented in Appendix 5.7. Results indicate that the difference in
SS is within the WQO criteria of 30% increase at all WSRs, except seawater
intake. At the seawater intakes (e.g. WSR 23 at LLP, WSR 43 at Tung Chung and WSR44
at BCF), the predicted SS levels are within the WSD criteria (i.e. <10 mg/L)
for the project scenario.
Total
Inorganic Nitrogen (TIN)
5.6.9.19
Table
A.1-A.8 in Appendix 5.7 compares the annual TIN levels between Scenario
01 and Scenario 02 at WSRs. Most of the WSRs comply with the WQO in TIN criteria of 0.5mg/L. The WSRs in Tung Chung Bay (WSR
01-03), the TIN level increases slightly. For example the TIN level increases
from 0.25mg/ L to 0.28mg/L at WSR 01 (Yat Tung East
Channel). However the TIN level is still within the criteria of 0.5mg/L.
However, the annual TIN level is still within 0.5mg/L criteria. At WSR 10 (Sha Chau and Lung Kwu Chau Marine Park). exceedance of the annual mean depth-averaged
TIN criteria is observed under the project scenario, which is in 0.53 mg/L. For
the without project scenario, exceedance of the annual
mean depth-averaged TIN criteria is also observed at WSR 10 by the same
magnitude. This suggests that the Tung Chung reclamation will
have insignificant effect on the TIN. The high TIN level is due to the background
from Pearl River estuary.
UIA (Unionised Ammonia, NH3)
5.6.9.20
Table
A.1-A.8 in Appendix 5.7 compare the
annual UIA levels between Scenario 01 and Scenario 02 at WSRs. The contours of UIA are presented in Appendix 5.7. The results show that the
depth-averaged UIA at WSRs would be within the WQO.
Sedimentation
5.6.9.21
Appendix 5.7 shows the
predicted annual sedimentation rate (m/year) for Scenario 01 and Scenario 02 by
assuming sediment density of 750 kg/m3, a sedimentation rate in
units of m/year is derived. The findings show that majority of locations would
experience no appreciable change in sedimentation rates after implementation of
the project. The only notable differences occur at Tung Chung estuary and coast
of TCE reclamation, whereby sedimentation is predicted to increase by less than
<0.4 mm per year after implementation of the project. This difference is
considered to be insignificant and is unlikely to lead to any adverse impacts
on WSRs.
E. coli
5.6.9.22
Table
A.1-A.8 in Appendix 5.7 compares the annual E. coli levels between Scenario 01 and Scenario 02 at WSRs. The contours of E. coli are presented in Appendix 5.7. The E. coli levels are within the WQO criteria which is 20,000 count/100ml at seawater intakes WSR 23 (LLP), WSR 43 (Tung Chung) and WSR 44 (BCF), 610 count/100ml
at fish culture zone WSR 20 (Ma Wan), 610 count/100ml
at secondary contact recreation subzone such as WSR 16 (Gold Coast Marina),
180 count/100ml for bathing season at beaches such as WSR 15 (Gazetted Beaches at Tuen Mun), WSR 18 (Gazetted beaches along Castle
Peak Road) and WSR 19 (Gazetted beaches at Ma Wan). No adverse impacts are
anticipated due to the implementation of the project.
5.6.10
Mitigation Measures
Emergency
Discharge of Proposed TCV West SPS, TCV East SPS, TCV North SPS, Upgraded CMRSPS, Proposed TCE
West SPS and TCE East SPS
5.6.10.1
For the protection of ecological sensitive
receivers of Tung Chug River and Tai Ho Bay, the
following mitigation measures will be implemented to TCV East, North and West
SPS, upgraded CMRSPS, Proposed TCE West SPS and TCE
East SPS:
¡P 100% standby pumping capacity with spare pump up to 50% pumping capacity
¡P
Twin
rising mains
¡P
Dual-feed
power supply
¡P Emergency storage facilities up to 6-hours ADWF capacity;
¡P Emergency communication mechanism amongst relevant government departments
With the implemented mitigation measures, emergency
sewage overflow to the Tung Chung Stream from SPSs in TCV or to the sea at the north side of
TCE from SPSs in TCE is not anticipated.
Emergency Discharge due to
Pipe Bursting
5.6.10.2
In
order to reduce the impact of emergency discharge due to pipe bursting, it is
proposed to adopt high density polyethylene (HDPE) pipe for proposed gravity
sewers and rising mains. As gravity sewers will not be
pressurized, they carry no risk of bursting. Further protection on proposed
rising mains with concrete surround will be provided to mitigate the risk of
bursting. With the above measures, bursting discharge is not expected and thus
no adverse impact on water quality due to bursting discharge is anticipated.
Maintenance Dredging for
the Proposed Marina
5.6.10.3
The
volume of dredged material would be relatively small as compared with the
construction phase impact. As the SS release would be within a semi-enclosed
bay, the dispersion of SS would be constrained locally. The SS impact to the
closest waiter sensitive receiver WSR 43 future seawater intake for Tung Chung,
which is located 1.2km far away from the mouth of marina, is not anticipated. Silt
curtain should be deployed to reduce the sediment dispersion from the dredging
inside the marina.
Conventional Measures by
Silt Trap and Road Cleaning in TCE and TCW
5.6.11.1 Under normal condition, surface runoff will not be generated in low
rainfall intensity. However, the worst scenario to water quality will take
place during the first flush under heavy rainstorm events. Under conventional
measures, surface runoff can be controlled by proper drainage systems with silt traps and best management
practice. Runoff would be intercepted by properly designed and managed silt
traps at appropriate spacing so that common roadside debris, refuse and fallen
leaves etc. can be captured before discharge. The road/ open area cleaning at
the drainage outlets should also be properly managed prior to the occurrence of
a storm. Manual methods and mechanical means such as vacuum sweeper/truck
equipped with side broom to increase removal efficiency of pollutants are the
common practices. The collected debris would be tankered
away for off-site disposal at landfill sites. After the removal of the debris,
the pollution levels from stormwater would be much
reduced. With
the implementation of silt traps and road cleaning, the impact to Tung Chung
Stream due to surface runoff is insignificant.
Introducing Sustainable Urban Drainage System
(SUDS) in TCW for Tung Chung Stream
5.6.11.2
Though the impact to Tung Chung Stream
due to surface runoff would be insignificant with the implementation of silt
traps and road cleaning, Sustainable Urban
Drainage System is introduced to further enhance the protection of Tung
Chung Stream. The existing catchment at TCW has an area of about 11km2.
It includes the upstream vegetated catchment of the North and South Lantau Country Park with scattered villages and the
downstream urban catchment of the Tung Chung Town. Tung Chung Stream is the
main river network serving this catchment area and it discharges downstream to
Tung Chung Bay. According to the DSD¡¦s List of Flooding Blackspots
(http://www.dsd.gov.hk/EN/Flood_Prevention/Our_Flooding_Situation/Flooding_Blackspots/index.html),
there is no DSD flooding blackspot within the
vicinity of the Project.
5.6.11.3
Unlike the conventional drainage system in
which surface runoff would pass through gullies to filter off dirt and debris
and then discharged into the receiving water bodies, the proposed SUDS within
TCW includes a number of new and innovative features to address the high
ecological concern of Tung Chung Stream and the downstream estuary. (See Section 9 for
more details). According to the latest design, the new system would include the
provision of a series of regional stormwater
attenuation and treatment ponds. During rainfall events, flows will be
directed into the stormwater attenuation
and treatment ponds which are capable to manage peak flows and
remove pollutants. Runoff from the
proposed development areas will be directed toward onsite stormwater attenuation and treatment ponds and the
treated runoff will be diverted back into
Tung Chung Stream. The ponds will have a vegetated wetland zone and
permanent pool, which will create valuable open space amenity and increase
biodiversity. The capacity of those
stormwater attenuation
and treatment ponds would vary from 3,000 ¡V 5,000m3,
depending on the catchment served.
5.6.11.4
As shown in Appendix 5.8, the runoff
from roadways, parcels, and existing villages will be diverted via dedicated
¡§dirty¡¨ pipe network and discharged to a primary sedimentation zone or ¡§forebay.¡¨ Runoff will be slowed to allow sediment to settle
out. Retaining sediment at the forebay rather than in
the larger detention zone will allow for easier removal, thus minimize
maintenance costs.
5.6.11.5
At the opposite end of the forebay,
runoff will enter a wide and shallow biofiltration
wetland zone. Treatment action will occur as stormwater
travels slowly through dense, climate-appropriate landscaping, removing floating
debris and encouraging the uptake of nutrients by the plants. Following the biofiltration wetland zone, treated flows will be
discharged into the permanent pool or attenuation zone.
5.6.11.6
During large rainfall events, high flows will
bypass the forebay and biofiltration
wetland zone and be directed into the attenuation zone. This zone will contain
high- and low-flow weirs to mitigate peak flows due to the planned development,
keeping the rate of discharge to the Tung Chung Stream at or below the existing
condition. In occasional high storm events in which the water level in Tung
Chung Stream is higher than that of the attention ponds, a high flow pump will
be activated to pump the water from the attenuation zone to the Tung Chung
Stream.
5.6.11.7
The sediment and pollutants in the runoff are
designed to be trapped within 3-stages of treatment pond. It should be noted
that some overseas examples similar to the proposed SUDS for TCW have been
successfully implemented for some years. (e.g. treatment pond at Bay Meadows,
California USA, attenuation pond at Land Port of Entry, Maryland USA,
sedimentation pond at Yishun Pond, Singapore etc). According to the USA studies, the substantial
pollutant removal performance by SUDS and treatment ponds are summarized in Table 5.38. As shown in the table,
sediment, nutrients, metals and bacteria can be removed in the SUDS and
treatment ponds.
Table 5.38 Substantial Pollutant
Removal Performance by SUDS and Treatment Ponds
|
¡§Polluted¡¨ Runoff
Containment |
SUDS Removal |
Treatment Ponds Removal |
¡§Treated¡¨
Runoff Containment |
Sediment |
100% |
80% |
80% |
4% |
Nutrients |
100% |
60% |
50% |
20% |
Metals |
100% |
70% |
60% |
12% |
Bacteria |
100% |
40% |
70% |
18% |
5.6.11.8
Besides, green channel design, such as grasscrete and gabion embankments etc., would be considered
in the design of drainage system to improve aesthetic and biodiversity, which
in turn enhancing the greening within the Tung Chung Valley. With the
implementation of SUDS, the pollution load to Tung Chung Stream due to
increased surface runoff would be further reduced.
5.6.11.9
Source-control SUDS techniques are aimed at
preventing pollutants from entering the storm drainage network by diverting
them to a controlled location for easy and low-cost removal. Some suitable
examples under consideration at proposed developments and within adjacent
villages include:
1) Street Sweeping ¡V maintain cleanliness of
street surfaces by routinely sweeping with a vacuum truck to remove organic
debris, litter, and sediment.
2) Vehicle Washing Stations ¡V construct
protected areas within each village dedicated to the washing of vehicles and
prohibit washing in other areas. The paved washing station should be
self-contained with runoff being diverted to an adjacent filter system or sanitary
sewer drain.
3) Educational Signage ¡V install signage near
storm drain inlets and along the banks of local streams to prevent illegal
dumping of concentrated pollutants and debris.
4) Oil/Water Separators ¡V install mechanical
or sand filtration devices within paved areas at the opening of storm inlets or
prior to the discharge of concentrated flows into local streams.
5) Discouraging the Use of Toxic Fertilizers ¡V
plant fertilizers, herbicides and pesticides are often washed away during rain
events or via irrigation runoff. Instead, encourage the use of organic mulch
and non-toxic products.
5.6.11.10 Treatment-control
SUDS techniques are aimed at removing pollutants that have been washed up by
the ¡§first-flush¡¨ of each rainfall event. Some examples under consideration at
Tung Chung Valley roadways and development parcels include:
1) Rain Gardens ¡V shallow vegetated
impoundments used to store and infiltrate runoff. Treatment occurs by
infiltration through the soil matrix where pollutants are trapped in the soil.
Treated stormwater is infiltrated to the native soil
or discharged via perforated subdrain.
2) Infiltration Planters ¡V similar to rain
gardens except constructed within a walled container such as a raised planter
box or kerbed impoundment.
3) Permeable Pavements ¡V load-bearing surface
that allows runoff to infiltrate through the surface. Treatment occurs by
infiltration of runoff into the native soil or via perforated subdrain.
4) Green Roofs ¡V vegetated ¡§green¡¨ roofs can
provide sustainable synergies, including improved insulation, reduction in
surface runoff and increased biodiversity.
5) Rainwater Harvesting ¡V roof downspouts are
diverted toward a localized storage tank where rainwater is treated and reused
for non-potable uses like irrigation and toilet flushing.
Polder
Scheme/ Stormwater Attenuation and Treatment Ponds
5.6.11.11 Due
to the high ecological sensitivity of the Tung Chung Stream and the low-lying
ground level along the banks of the east and west streams, a polder scheme is
proposed to provide adequate flood protection to existing and proposed
developments. Each development parcel within the polder scheme will contain a stormwater
attenuation and treatment ponds to manage peak flows and remove pollutants. The
treated runoff will be diverted back into
Tung Chung Stream.The ponds will have a vegetated wetland zone and
permanent pool during the wet season, which will create valuable open space
amenity and increase biodiversity.
5.6.11.12 A diversion storage is proposed by installing several 1m
diameter pipes below the proposed roadways and polder levees to offset the loss
of flood storage volume at the Tung Chung Stream due to the proposed polder
scheme. The pipes will serve dual purpose as the main gravity conveyance
network during small rain events and as flood diversion storage from the east
and west stream during large rainfall events. In the dry season, water quality deterioration due to stagnant situation in the stormwater attenuation and treatment ponds would be
avoided with the implementation of suitable design
measures, such as installation of subsurface drainage to eliminate areas of
standing water, implementation of maintenance activities to remove any organic
debris and to clear areas of stagnation etc., to be determined during detailed
design stage to ensure compliance with the WPCO discharge standards. The
conceptual layout of polder scheme is presented in Appendix 5.8.
5.6.11.13 It
should be noted that for the sake of conservation, the water quality assessment
has not included the effectiveness of the SUDS. The assessment results show
that the water quality will still comply with WQO even for the worst case
scenario.
Dry
Weather Flow Interception (DWFI) at the Existing Villages
5.6.11.14 A
new public sewerage system will be provided to serve the TCW development as
well as to provide village sewers to the existing village areas (including Shek Mun Kap,
Mok Ka, Nim
Yuen, Lam Che, Ngau Au, Shek Lau Po, Ma Wan Chung and Wong Nai
Uk). New sewers will be laid
along existing and proposed roads, footways or drainage reserves.
5.6.11.15 According
to TM-DSS, the effluent should not be discharged into the storm water drain.
However, there may be illicit discharge to the drainage system from the village
and the water quality of stormwater
attenuation and treatment ponds in dry season would be deteriorated. In order
to mitigate the risk of illicit connections of sewage flow to the drainage
network, DWFI is proposed at the connection point of each village to the public
drainage network. The interceptor will contain a penstock to divert and retain
the very low flows to a nearby chamber for disposal to sewage treatment works
or other disposal facility, by tankering away or
other conveyance method approved by EPD.
5.6.12
Residual Impacts
5.6.12.1
No residual adverse water quality impact is
anticipated in operational phase.
Construction
Phase
5.7.1.1
While reclamation work in TCW has been removed
to avoid water quality impacts as much as practicable, reclamation works at TCE
is still required. Potential key sources of water quality impact during the
construction phase include land formation works in TCE and Road P1; land
improvement by deep cement mixing, construction of new seawall, stone column
installation. It should be noted that potential construction phase water
quality impacts associated with the proposed works have already been
substantially reduced by the adoption of non-dredged reclamation methods for
land formation and reclamation filling works within a leading seawall of about
200m. Other than reclamation works, the construction work in both TCE and TCW
would involve construction site runoff and drainage; sewage effluent from
construction workforce.
5.7.1.2
A quantitative assessment of potential water
quality impacts associated with marine construction works has also been
conducted, taking into account the critical periods for Suspended Sediment (SS)
release. Other activities that could affect water quality during construction
are primarily land-based and were assessed qualitatively.
5.7.1.3
Assessment results show that with the
application of about 200m leading edge of partially completed seawall prior to
marine filling activities and the implementation of mitigation measures (in the
form of silt curtains and silt screens where applicable), there will be no exceedance of the SS criteria at any WSR due to project
activities. However, when taking into account of the SS release from concurrent
projects, cumulative exceedance is predicted at few WSRs near the Brothers Islands. Nevertheless, the exceedances are primarily due to the conservative
assumptions for the concurrent projects rather than due to the contributions
from the Tung Chung project. Those conservative assumptions are based on the
maximum allowable SS release rates of the relevant concurrent project. However,
based on the available information, the actual SS release rates are much lower
than the maximum allowable release rates. Therefore, adverse residual water
quality impacts due to the project are not anticipated.
5.7.1.4
A sensitivity scenario has also been conducted
to address the potential shift in the implementation date of the 3RS. Results indicate that, given the
separation between the 3RS and the Tung Chung New Town Extension, even under
the worst case scenario, the construction of 3RS would not cause significant
cumulative impacts on the water sensitive receivers in Tung Chung Bay, and vice
versa, the construction activities in Tung Chung would also not cause
significant water quality impacts on the sensitive receivers near the 3RS. By comparsion of the concurrent scenario and the above
sensitivity scenario, exceedance at coral communities
at the Brothers Islands is due to the conservative SS release assumption in
concurrent projects. Non exceedance at Marine Parks
of Brothers Islands is due to the hydrodynamics
change without the landform of 3RS reclamation.
5.7.1.5
Other construction activities include bridge
works at Tung Chung Stream, construction work of sewage pumping stations, fresh
water and salt water reservoirs, water management facilities and polder scheme,
proposed marina and groundwater and runoff for tunnel works. With the
implementation of good site practices and the recommended mitigation measures
to minimise potential water quality impacts, these construction activities, as
well as general construction site drainage and sewage effluent from the
construction workforce, are not anticipated to result in significant water
quality impacts.
5.7.1.6
In view of the assessment findings, it is
concluded that no adverse residual water quality impacts are anticipated during
the construction phase of the project.
Operational Phase
5.7.1.7
The potential key sources of water quality
impact during the operational phase include changes in hydrodynamics as a
result of the reclaimed land in TCE and Road P1 and the increase of sewage
amount and increase of pollution load from surface runoff.
5.7.1.8
For the reclamation in TCE and Road P1, quantitative
assessments for ¡¥with project¡¦ and ¡¥without project¡¦ scenarios were undertaken
for the assessment year of Year 2030 which represents the worst case for
pollution loading, taking into account other planned and committed concurrent
projects in the study area. The
findings show that despite minor exceedances in total
inorganic nitrogen (TIN) at some WSRs, these were attributed from the
background concentration but not significantly attributed to the Project. On
comparing the without project case and the existing monitoring data (Section 5.2.3), the exceedance
is still exist. The predicted water quality in annual mean of depth averaged at
the representative WSRs is summarized in below table. Therefore, implementation
of the project would not result in adverse hydrodynamic and water quality
changes in the study area.
5.7.1.9
The assessment has also demonstrated that the
proposed reclamation works would not cause significant change in the water
quality at the water sensitive receivers including the estuary of Tung Chung
Stream and inside Tai O Bay.
5.7.1.10 In
order to protect the water quality of Tung Chung Stream, Tai Ho Wan and other neighbouring water body, all the sewage
pumping stations serving the TCE and TCW will be designed with appropriate
design to avoid the need for emergency discharge. For the surface runoff from
TCW, enhancement measures such as provision of stormwater
attenuation and treatment ponds, dry weather flow interception at the
existing villages have been recommended to protect the water quality in Tung
Chung Stream.
[1] Binnie Consultants Limited (1996). Fill Management Study - Phase IV Investigations and Development of Marine Borrow Areas: Coral Growth at High Island Dam. For The Civil Engineering Department, Hong Kong SAR Government.
[2] Meinhardt Infrastructure and Environment (2007). Contract P325 Environmental Assessment Services for Permanent Aviation Fuel Facility. Final Environmental Impact Assessment Report. Prepared for Airport Authority Hong Kong.
[3] Mouchel Asia Limited (2002). Environmental Assessment Study for Backfilling of Marine Borrow Pits at North of the Brothers (Agreement No Geo 01/2001) ¡V Environmental Assessment Report. For The Civil Engineering Department, Hong Kong SAR Government.
[4] Where C(x) = concentration at distance x from the source, q = sediment loss rate, D = water depth, x = distance from source, £s = diffusion velocity (=0.01 m/s).
[5] Hong Kong - Zhuhai - Macao Bridge Hong Kong Boundary Crossing Facilities (AEIAR-145/2009).
[6] Hong Kong - Zhuhai - Macao Bridge Hong Kong Link Road (AEIAR-144/2009).
[7] 132 KV Supply Circuit from Pui O via Chi Ma Wan Peninsula via Sea Crossing towards Cheung Chau (AEIAR-051/2002).
[8] Construction of an International Theme Park in Penny's Bay of North Lantau together with its Essential Associated Infrastructures - Environmental Impact Assessment (AEIAR-032/2000).
[9] Redfield A.C., On the proportions of organic derivations in seawater and their relation to the composition of plankton. In James Johnson Memorial Volume (ed. R.J. Daniel). University Press of Liverpool, pp.177-192, 1934.
[10] I. J. Hodgkiss & K. C. Ho (1997) Are changes in N:P ratios in coastal waters the key to increased red tide blooms? Hydrobiologia 352:141-147.