Table 3.1 Hong Kong Air Quality Objectives
Pollutant |
Maximum Concentration (µg m-3) (1) |
|||
Averaging Time |
||||
1 hour (2) |
8 hour (3) |
24 hour (3) |
Annual (4) |
|
- |
- |
260 |
80 |
|
Respirable
Suspended Particulates (RSP) (5) |
- |
- |
180 |
55 |
Sulphur Dioxide
(SO2) |
800 |
- |
350 |
80 |
Nitrogen
Dioxide (NO2) |
300 |
- |
150 |
80 |
Carbon Monoxide
(CO) |
30,000 |
10,000 |
- |
- |
Photochemical
Oxidants (as Ozone, O3)
(6) |
240 |
- |
- |
- |
Note:
(1)
Measured at 298 K and 101.325 kPa.
(2)
Not to be exceeded more than three times per year.
(3)
Not to be exceeded more than once per year.
(4)
Arithmetic mean.
(5)
Suspended particulates in air with a nominal aerodynamic diameter of 10
mm or smaller.
(6)
Photochemical oxidants are determined by measurement of ozone only.
Table 3.2 Tunnel Air Quality Guidelines (TAQG)
Air Pollutant |
Averaging Time |
Maximum Concentration |
|
(mg/m3) (1) |
ppm |
||
Carbon Monoxide (CO) |
5 minutes |
115, 000 |
100 |
Nitrogen Dioxide (NO2) |
5 minutes |
1,800 |
1 |
Sulphur Dioxide (SO2) |
5 minutes |
1,000 |
0.4 |
Note: (1) Expressed at reference conditions of
298K and 101.325kPa.
Table 3.3 EPD Air Quality Monitoring Data at Kwun Tong Station in 2001
Pollutant |
Annual Average Concentration (μg/m3) |
SO2 |
15 |
NO2 |
75 |
Ozone |
25 |
TSP |
79 |
RSP |
56 |
ID No. |
Location |
Use |
Distance between ASR and work
boundary(m) |
OP1 |
Residential |
252 |
|
V1 |
Village Houses
in vicinity of Eastern Portal of WCR |
Residential |
74 |
OSC2 |
Ocean Shore |
Residential |
32 |
H3 |
Private
Residential Development at the north of WCR (Planned) |
Residential |
30 |
H11 |
Private
Residential Development at the north of WCR (Planned) |
Residential |
12 |
T1 |
Tin Hau Temple,
south of KMS Development |
Temple |
25 |
PW |
Ping Tin Estate |
Residential |
96 |
CP |
Chung Pak
House, Hong Pak Court |
Residential |
42 |
EHC1 |
Residential
Development near Eastern Harbour Crossing (Under Construction) |
Residential |
8 |
Table 3.5 Representative Air Sensitive Receivers in the vicinity of Kowloon Section of WCR during Operation Phase
ID No. |
Location |
Use |
Distance between ASR and emission
sources (m) |
LC1 |
Residential |
20 |
|
CKL1 |
Existing
Residential Development along Cha Kwo Ling Road – Cha Kwo Ling Building |
Residential |
2 |
CKL2 |
Existing
Residential Development along Cha Kwo Ling Road – Hoi Chu Building |
Residential |
2 |
HS1 |
School Village
of Kaolin Mine Site |
Educational Institute |
80 |
HS4 |
School Village
of Kaolin Mine Site |
Educational Institute |
26 |
H1 |
Private
Residential Development at the north of WCR (Planned) |
Residential |
55 |
H3 |
Private
Residential Development at the north of WCR (Planned) |
Residential |
46 |
H11 |
KMS Housing
Development at the South of WCR (Planned) |
Residential |
22 |
H12 |
KMS Housing
Development at the South of WCR (Planned) |
Residential |
46 |
H15 |
KMS Housing
Development at the South of WCR (Planned) |
Residential |
44 |
H17 |
KMS Housing
Development at the South of WCR (Planned) |
Residential |
44 |
H20 |
KMS Housing
Development at the South of WCR (Planned) |
Residential |
22 |
T1 |
Tin Hau Temple,
south of KMS Development |
Temple |
30 |
S1 |
CCC Kei Fat
Primary School (Under Construction) |
Educational Institute |
13 |
SG1 |
Block 9,
Sceneway Garden |
Residential |
28 |
KH |
SKH Kei Hau
Secondary School |
Educational Institute |
20 |
PW |
Ping Tin Estate |
Residential |
80 |
CP |
Chung Pak
House, Hong Pak Court |
Residential |
120 |
EHC1 |
Residential
Development near Eastern Harbour Crossing (Under Construction) |
Residential |
13 |
EHC2 |
Residential
Development near Eastern Harbour Crossing (Under Construction) |
Residential |
13 |
EHC5 |
Residential
Development near Eastern Harbour Crossing (Under Construction) |
Residential |
13 |
STA |
St. Antonius
Primary School and Kindergarten |
Educational Institutes |
33 |
AMB |
Lam Tin
Ambulance Depot |
Clinic |
24 |
Table 3.6 Representative Air Sensitive Receivers in the vicinity of TKO Town Centre South during Operation Phase
ID No. |
Location |
Use |
Distance between ASR and emission
sources (m) |
73Bb |
Residential |
37 |
|
73Bd |
Area 73B –
Planned residential Area (R1) |
Residential |
7 |
OSC2 |
Residential |
36 |
|
OSC5 |
Area 72 – Ocean
Shores |
Residential |
127 |
OSC8 |
Area 72 – Ocean
Shores |
Residential |
5 |
TKC2 |
Area 57 – Park
Central |
Residential |
42 |
TKC6 |
Area 57 – Park
Central |
Residential |
36 |
TKC12 |
Area 57 – Park
Central |
Residential |
27 |
TKC13 |
Area 57 – Park
Central |
Residential |
38 |
TKP2 |
Area 55 – Site
55A – Tseung Kwan O Plaza |
Residential |
38 |
TKP5 |
Area 55 – Site
55A – Tseung Kwan O Plaza |
Residential |
19 |
BaG1 |
Area 65 – Site
65A – Bauhinia Garden |
Residential |
39 |
BaG3 |
Area 65 – Site
65A – Bauhinia Garden |
Residential |
39 |
BaG11 |
Area 65 – Site
65A – Bauhinia Garden |
Residential |
12 |
V1 |
Residential |
102 |
|
74S4 |
Area 74S –
Planned School Area |
Educational Institutes |
23 |
74S5 |
Area 74S –
Planned School Area |
Educational Institutes |
37 |
74S6 |
Area 74S –
Planned School Area |
Educational Institutes |
56 |
73B1 |
Area 73B –
Planned School Area |
Educational Institutes |
45 |
73B2 |
Area 73B –
Planned School Area |
Educational Institutes |
8 |
73B3 |
Area 73B –
Planned Residential Area (R1) |
Residential |
9 |
73B4 |
Area 73B –
Planned Residential Area (R1) |
Residential |
10 |
73B5 |
Area 73B –
Planned Residential Area (R1) |
Residential |
19 |
SAPS |
At. Andrew’s
Catholic Primary School |
Educational Institutes |
2 |
67S1 |
Area 67 –
Planned School Area |
Educational Institutes |
29 |
67S2 |
Area 67 –
Planned School Area |
Educational Institutes |
18 |
67S4 |
Area 67 –
Planned School Area |
Educational Institutes |
24 |
67S6 |
Area 67 –
Planned School Area |
Educational Institutes |
22 |
66A2 |
Area 66 – Site
66A – Planned Residential Area (R1) (with 3 storeys commercial development at
lower levels) |
Residential |
12 |
66A3 |
Residential |
21 |
|
66B1 |
Residential |
9 |
|
66B3 |
Area 66 – Site
66B – Planned Residential Area (R1) (with 3 storeys commercial development at
lower levels) |
Residential |
16 |
66B5 |
Area 66 – Site
66B – Planned Residential Area (R1) (with 3 storeys commercial development at
lower levels) |
Residential |
9 |
55B1 |
Area 55 – Site
55B – Tseung Kwan O Plaza (Phase2) |
Residential |
43 |
65B1 |
Area 65 – Site
65B – Planned Residential Area (R2) |
Residential |
65 |
65B2 |
Area 65 – Site
65B – Planned Residential Area (R2) |
Residential |
15 |
65B3 |
Area 65 – Site
65B – Planned Residential Area (R2) |
Residential |
14 |
65C1 |
Area 65 – Site
65C – Planned School Area |
Educational Institutes |
11 |
65C2 |
Area 65 – Site
65C – Planned School Area |
Educational Institutes |
12 |
66C1 |
Area 66C –
Planned Other Specified Uses Area including Residential Uses |
OU |
24 |
66C2 |
Area 66C –
Planned Other Specified Uses Area including Residential Uses |
OU |
14 |
66C3 |
Area 66C –
Planned Other Specified Uses Area including Residential Uses |
OU |
12 |
68A1 |
OU |
38 |
|
78B1 |
Area 78 –
Planned Residential Area (R3) (Site 78C) |
Residential |
25 |
78B2 |
Area 78 –
Planned Residential Area (R3) (Site 78A) |
Residential |
15 |
78E1 |
Area 78 –
Planned Residential Area (R3) (Site 78E) |
Residential |
79 |
78E3 |
Area 78 –
Planned Residential Area (R3) (Site 78E) |
Residential |
37 |
78E5 |
Residential |
16 |
|
78E6 |
Area 78 –
Planned Residential Area (R3) (Site 78E) |
Residential |
15 |
S1 |
Area 78 –
Planned School |
Educational Institute |
48 |
S2 |
Area 78 –
Planned School |
Educational Institute |
43 |
N4 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
15 |
N10 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
20 |
N14 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
12 |
N16 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
2 |
N19 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
24 |
N22 |
Area 86 – MTRC
Area 86 Development (Under Construction) |
Residential |
6 |
MTR |
MTR Tseung Kwan
O Extension - Tiu Keng Leng Station |
OU |
8 |
·
Package 1: TCS, Tiu Keng Leng (TKL) and PSK & Tseung Kwan O Stage I Landfill (TKOL-1) Development:
- TCS comprise the
newly reclaimed land south of Po Yap Road, Eastern Drainage Channel and the toe
along TKOL-1;
- TKL comprise the
newly reclaimed land on the east of Ocean Shores (South of Chui Ling Road);
- PSK comprise the
three large terraces on the east of TKOL-1 and Wan Po Road;
·
Package 2: Western Coast Road including reclamation & toll plaza
& at-grade road at TKO, tunnel, Kowloon viaduct and road;
·
Package 3: Cross Bay Link;
·
Package 4: Road P2 & Road D4 Flyover.
Case 1 - O Pui Village houses (ASR OP1) due to site
formation at Pak Shing Kwok;
Case 2 - Villages houses (V1) in vicinity of Eastern
Portal of the WCR due to Reclamation Work Phase 2;
Case 3 - Ocean
Shores (ASR OSC2) due to Reclamation Work Phase 3; and
Case 4 - ASRs
(ASR H3, H11 and T1) at Kaolin Mine Development and ASRs (ASR PW, CP and EHC1)
in vicinity of Western Portal of the WCR at Kowloon side due to construction of
WCR and Western Portal of WCR.
(A) Kowloon
Area (Kowloon section of WCR)
·
Vehicular emissions from road networks.
·
Portal emissions from the proposed WCR, the existing EHC, deck-over of
Sceneway Garden and the Lei Yue Mun Road underpass (planned).
·
Emissions from idling traffic at the toll plaza section of EHC.
·
Emissions from the EHC exhaust ventilation building.
·
Vehicular emissions inside tunnel of WCR and the proposed full
enclosure.
·
Flaring plant located at the Sai Tso Wan Landfill.
·
Industrial emissions from factories in Kwun Tong and Yau Tong.
(B) TKO
Area (including TKO section of WCR, TKO TCS, CBL & PSK)
·
Vehicular emissions from road networks.
·
Portal emissions from the WCR Tunnel, underpass section of link roads
at WCR/CBL/Road P2 interchange and depressed Road P2.
·
Emissions from idling traffic at the toll plaza of eastern portal of WCR.
·
Emissions from the Mid-Ventilation Building.
·
Flaring emissions from TKO Stage I and Stage II/III Landfills.
Case 1 Pak Shing Kok Site Formation
(levelling and filing)
-
sand
filling activities
-
truck movement
on unpaved haul road within the construction site
-
wind
erosion of open site
Pak Shing Kok Fresh Water Service Reservoir
-
soil
excavation activities
-
transportation
/ handling of spoil
-
wind
erosion of open site.
Case 2 Reclamation Works at TKO (Phase
II)
-
backfilling
-
transportation
/ handling of spoil
-
truck
movement on unpaved haul road within the construction site
-
wind
erosion of open site
Case 3 Reclamation Works at TKO
(Phase III)
-
backfilling
-
transportation
/ handling of spoil
-
truck
movement on unpaved haul road within the construction site
-
wind
erosion of open site
Case 4 Construction works of WCR
& Western Portal of WCR
-
cut
& cover tunnel (near Kaolin Site) & aggregate handling
-
soil
excavation
-
transportation
/ handling of spoil
-
truck
movement on unpaved haul road within the construction site
-
wind
erosion of open site
Table 3.7 Emission Factors for Dusty Construction Activities
Scenario |
Activity |
|
Emission Rate |
Remarks |
Case 1 |
Pak Shing Kok Site Formation (levelling and filling) |
Material Handling |
E = 0.1083
g/Mg =1.706 x 10-3
g/s |
·
Volume of material:
567 m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
Unpaved Haul Road |
E=344.7 g/VKT =2.394 x 10-3
g/m/s |
·
Silt content: 10% ·
Moisture content: 10% ·
Vehicle speed: 10 kph ·
No. of vehicle: 50
trips/hr ·
50% reduction by water
suppression. ·
AP42, Section 13.2.2 |
||
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x 10-6
g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
||
Pak Shing Kok
Fresh Water Service Reservoir |
Material
Handling |
E = 0.1083
g/Mg =8.424 x 10-5
g/s |
·
Volume of material: 28
m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
|
Wet drilling |
E = 8.4 x
10-5 kg/Mg =6.533 x 10-5
g/s |
·
Volume of material: 28
m3/day ·
50% reduction by water suppression. ·
AP42, Section 11.19.2 |
||
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x 10-6
g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
||
Case 2 Reclamation Works at TKO |
Phase II |
Material Handling |
E = 0.1083
g/Mg = 1.805 x
10-2 g/s |
·
Volume of material:
6000 m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
Phase II |
Unpaved Haul Road |
E=344.7 g/VKT =2.394 x 10-3
g/m/s |
·
Silt content: 10% ·
Moisture content: 10% ·
Vehicle speed: 10 kph ·
No. of vehicle: 50
trips/hr ·
50% reduction by water
suppression. ·
AP42, Section 13.2.2 |
|
Phase II |
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x
10-6 g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
|
Case 3 Reclamation
Works at TKO |
Phase III |
Material
Handling |
E = 0.1083
g/Mg = 9.025 x 10-3
g/s |
·
Volume of material:
3000 m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
Phase III |
Unpaved Haul
Road |
E=344.7 g/VKT =2.394 x 10-3
g/m/s |
·
Silt content: 10% ·
Moisture content: 10% ·
Vehicle speed: 10 kph ·
No. of vehicle: 50
trips/hr ·
50% reduction by water
suppression. ·
AP42, Section 13.2.2 |
|
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x 10-6
g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
||
Case 4 Construction
works of WCR and Western Portal of WCR |
Cut & Cover
Tunnel (near Cha Kwo Ling Kaolin Mine Site) |
Material
Handling |
E = 0.1083
g/Mg = 8.273 x 10-4
g/s |
·
Volume of material:
275 m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
Cut & Cover
Tunnel (near Cha Kwo Ling Kaolin Mine Site) |
Wet Drilling |
E = 8.4 x 10-5
kg/Mg = 6.417 x 10-4
g/s |
·
Volume of material:
275 m3/day ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 11.19.2 |
|
Cut & Cover
Tunnel (near Cha Kwo Ling Kaolin Mine Site) |
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x 10-6
g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
|
Construction of
WCR |
Material Handling |
E = 0.1083
g/Mg =8.123 x 10-4
g/s |
·
Volume of material:
270 m3/day ·
Moisture content: 10 % ·
Average wind speed:
1.98 m/s ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 13.2.4 |
|
Construction of
WCR |
Wet drilling |
E = 8.4 x 10-5
kg/Mg = 6.3 x 10-4
g/s |
·
Volume of material:
270 m3/day ·
Density of spoil: 2
Mg/m3 ·
50% reduction by water suppression. ·
AP42, Section 11.19.2 |
|
Construction of
WCR |
Unpaved Haul
Road |
E=344.7 g/VKT =1.436 x 10-3
g/m/s |
·
Silt content: 10% ·
Moisture content: 10% ·
Vehicle speed: 10 kph ·
No. of vehicle: 30
trips/hr ·
50% reduction by water
suppression. ·
AP42, Section 13.2.2 |
|
Construction of
WCR |
Wind Erosion |
E = 0.85
Mg/hectare/year = 1.348 x 10-6
g/m2/s |
·
50% reduction by water
suppression. ·
AP42, Section 11.9.4 |
Daily TSP concentration = (working hour)/24 ´ (1-hour average maximum TSP
concentration during working hours) + (non-working hour)/24 ´ (1-hour average maximum TSP
concentration during non-working hours) + Background
Table 3.8 Queuing Forecast at EHC Toll Plaza
EHC Toll Plaza |
Maximum Steady Queue (No. of vehicles) |
Eastbound |
80 |
Westbound |
80 |
Table 3.9 Queuing Forecast at WCR Toll Plaza
WCR Toll Plaza |
Maximum Steady
Queue (No. of vehicles) |
Eastbound |
80 |
Westbound |
93 |
Table 3.10 Vehicle Idling Emission Factors
Vehicle Type |
Idling Emission
Factor (g/min/veh) |
|
NOx |
RSP |
|
Public Light Bus, Light Goods Vehicles |
0.5 |
0.043 |
Bus, Medium Goods Vehicles and Heavy Goods
Vehicles |
2.0 |
0.043 |
Taxi |
0.5 |
0.043 |
Private Car |
0.2 |
Negligible |
Table 3.11 Pollutant Emission Limits and Operational Parameters of Sai Tso Wan Landfill Flare
Parameters |
|
Emission Limit of NOx (mg/m3) |
400 |
Emission Limit of RSP (mg/m3) |
50 |
Exhaust Volume Flow Rate (m3/hr) |
19,110 |
Flare Stack Height (m) |
6 |
Flare Stack Diameter (m) |
1 |
Exit Temperature (°C) |
900 |
Remark: Reference from Final Report of
Feasibility Study for Developments at Cha Kwo Ling Kaolin Mine Site.
·
Wind direction: 360 wind direction
·
Surface roughness: 1m
Table 3.12 Background Air Pollutant Concentration for Urban Development
Parameters |
Concentration (mg/m3) |
Sulphur Dioxide |
19 |
Nitrogen Dioxide |
64 |
Ozone |
27 |
TSP |
77 |
RSP |
51 |
Table 3.13 Predicted TSP Concentrations at Representative Air Sensitive Receivers
Scenarios |
ASRs ID |
TSP Concentration (mg/m3) |
|
1 – hour Average |
24 – hour Average |
||
Case 1 |
OP1 |
499 |
277 |
Case 2 |
V1 |
519 |
319 |
Case 3 |
OSC2 |
995 |
551 |
Case 4 |
H3 |
366 |
217 |
H11 |
366 |
219 |
|
T1 |
285 |
195 |
|
PW |
206 |
145 |
|
CP |
278 |
195 |
|
EHC1 |
456 |
269 |
Remark: Background TSP concentration of 77 mg/m3 is included.
·
Open road sections.
·
WCR tunnel portals.
·
Recommended noise enclosures on WCR.
·
Existing roads including EHC, Lei Yue Mun Road underpass (planned) and
the deck-over of Sceneway Garden; idling emissions from EHC toll plaza;
emissions from EHC vent shafts.
·
Chimney emissions in the Yau Tong industrial area.
·
Landfill gas flaring plant emissions.
·
Open road sections
·
WCR tunnel portals
·
Mid-Ventilation Building of WCR Tunnel
·
Decked sections of Road P2
·
Tunnel sections of link roads of WCR/ CBL Road P2 interchange
·
Idling vehicles queuing at the WCR toll plaza
·
Flaring emissions from TKO Stage I and Stage II/III Landfills
·
Use
of regular watering, with complete coverage, to reduce dust emissions from
exposed site surfaces and unpaved roads, particularly during dry weather.
·
Use
of frequent watering for particularly dusty construction areas and areas close
to ASRs.
·
Side
enclosure and covering of any aggregate or dusty material storage piles to
reduce emissions. Where this is not
practicable owing to frequent usage, watering shall be applied to aggregate
fines.
·
Open
stockpiles shall be avoided or covered.
Where possible, prevent placing dusty material storage piles near ASRs.
·
Tarpaulin
covering of all dusty vehicle loads transported to, from and between site
locations.
·
Establishment
and use of vehicle wheel and body washing facilities at the exit points of the
site.
·
Provision
of wind shield and dust extraction units or similar dust mitigation measures at
the loading points, and use of water sprinklers at the loading area where dust
generation is likely during the loading process of loose material, particularly
in dry seasons/ periods.
·
Imposition
of speed controls for vehicles on unpaved site roads. Ten kilometers per hour is the recommended limit.
·
Where
possible, routing of vehicles and positioning of construction plant should be
at the maximum possible distance from ASRs.
·
Instigation
of an environmental monitoring and auditing program to monitor the construction
process in order to enforce controls and modify method of work if dusty
conditions arise.
For PSK site formation (levelling & filling) and Construction of WCR
·
Strictly
limit the truck speed on site not more than 10 km per hour and watering the
haul roads at least 4 times a day to reduce the dust generation by 75%, with
reference to Control Techniques for Particulate Emissions from Stationary
Sources, Volume 2, US Environmental Protection Agency 1982..
For WCR reclamation works phase 2 & 3
·
Strictly
limit the truck speed on site not more than 10 km per hour and water spraying
to keep the haul roads in wet condition.
This will reduce the dust generation by about 90%, in accordance with Control
Techniques for Particulate Emissions from Stationary Sources, Volume 2, US
Environmental Protection Agency 1982.
Table 3.14 Emission Factors for Dusty Construction Activities (With Mitigation Measures)
Scenario |
Activity |
Emission Rate |
|
Case 1 Pak Shing Kok Site Formation (levelling and
filling) |
Site formation |
Unpaved Haul Road Wind Erosion |
E = 1.197 x 10-3 g/m/s E=6.738 x 10-7 g/m2/s |
Cases 2 & 3 Reclamation Works at TKO |
Phases II & III |
Unpaved Haul Road Wind Erosion |
E = 4.787 x 10-4 g/m/s E=2.695 x 10-7 g/m2/s |
Case 4 Construction works of WCR and Western Portal of WCR |
Construction of WCR |
Unpaved Haul Road Wind Erosion |
E = 7.181 x 10-4 g/m/s E= 6.738x 10-7 g/m2/s |
Table 3.15 Predicted TSP Concentrations at Representative Air Sensitive Receivers (Mitigated)
Scenarios |
ASRs ID |
TSP Concentration (mg/m3) |
|
1 – hour Average |
24 – hour Average |
||
Case 1 |
OP1 |
303 |
195 |
Case 2 |
V1 |
220 |
169 |
Case 3 |
OSC2 |
298 |
203 |
Case 4 |
EHC1 |
281 |
196 |
Remark: Background TSP concentration of 77 mg/m3 is included.
· Provision of a ventilation building at the eastern portal of WCR (Eastern Portal Ventilation Building) and it should be designed to extract 70% of the tunnel emission from the eastbound carriageway of the WCR tunnel. Then 30% of the tunnel emission from eastbound carriageway would be discharged through the WCR portal at the TKO area. The exhaust vent shaft of the ventilation building are proposed to be designed to exhaust in upward direction and the exhaust height should be at least 25m above ground level to prevent adverse air quality impact on the nearby ASRs (e.g. ASR V1).
· The Mid-ventilation building should be relocated from Tiu Keng Leng to the proposed reclamation area near CBL/WCR/Road P2 Interchange. The mid-ventilation building on the reclamation area should be at least 350 m to south of Ocean Shores. There would be two exhaust vent pipes discharge the in-tunnel air to the exhaust vent shaft. The exhaust vent shaft of the ventilation building would be upward direction with the exit velocity of 16 m/s, and release height would be 6 m above ground.
· The preliminary design of the ventilation buildings (including exit height, exhaust directions, exit velocity, design airflow rate and the exhaust diameter of the ventilation building) is summarized in Table 3.16.
Table 3.16 Design of Ventilation Building at the eastern portal of WCR and Mid-Ventilation building
|
Design Airflow
Rate (m3/s) |
Exit Velocity
(m/s) |
Exit Height (m) |
Exhaust
Diameter (m) |
Exhaust
Direction |
|
Ventilation Building at eastern portal |
321 |
16 |
25 |
5.1 |
Upward |
|
Mid-Ventilation Building |
Vent 1 |
228 |
16 |
6 |
4.3 |
Upward |
Vent 2 |
210 |
16 |
6 |
4.1 |
Upward |