Table 3.1 Hong Kong Air Quality Objectives
Parameter |
Maximum Average Concentration (µgm-3)1 |
||
|
1-Hour2 |
24-Hour3 |
Annual4 |
NO2 |
300 |
150 |
80 |
RSP |
----- |
180 |
55 |
TSP |
----- |
260 |
80 |
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.
Table 3.2 Tunnel Air Quality Criteria
Parameter |
Maximum Concentration1, 2 |
|
CO |
115,000 µgm-3 |
100 ppm |
NO2 |
1,800 µgm-3 |
1 ppm |
SO2 |
1,000 µgm-3 |
0.4ppm |
1 Averaging time is 5 minutes
2 Measured at 298 K and 101.325 kPa.
Baseline Condition
Table 3.3 Maximum Predicted SO2, NO2 and TSP Concentrations from the Separate EA Study for Area 86
Pollutants |
Modelled Concentration (with background), mgm-3 |
Assessment Criteria, mgm-3 |
|
SO2 |
Highest 1-hr |
345.7 at southeast of
Area 86 |
800 |
NO2 |
Highest 1-hr |
52.5 at north of Area
86 |
300 |
TSP |
Daily |
184 at east of Area 86 |
260 |
Table 3.4 Air Pollutant Levels Recorded at EPD Air Quality Monitoring Stations
Pollutants |
Annual Average
Concentrations (mgm-3) |
||
|
TKO (1993) |
Tai Po (1997) |
Tai Po (2000) |
NO2 |
21 |
50 |
47 |
RSP |
39 |
55 |
48 |
TSP |
77 |
80 |
63 |
Air sensitive receivers
Construction
Phase
·
Road
D1 (2003-2006)
·
Road
D8 (2003-2006)
·
Town
Centre Link, Road D10 (2003-2007)
·
Minor
road junction improvement works at road junction of Road D10 / Wan Po Road, and
road junctions along Roads D1 and D8 (2002-2009)
·
Extended
Road P2 (2003-2010)
·
Cross
Bay Link, Road D9 (2003-2011)
·
Road
D6 (2003-2008)
·
Minor
road junction improvement works at road junctions of Road D9 / Wan Po Road,
Road D6 / Wan Po Road, and road junctions along D4 and P2 (2002-2009)
·
Water
Supply Infrastructure (2003-2007/08)
·
Area
86 (2000-2010)
·
Area
65D and 67 (indicative and may be completed before 2007)
·
Site
formation work for the possible future development of Pak Shing Kok (Area 78)
(2003-2008)
·
Possible
future development to the south of Road D1 and the associated roads and drains
in the development (indicative and may be constructed in 2005-2013)
Table 3.5 Description of Air Sensitive Receivers (ASRs) during Construction Phase in Year 2005
ASR ID |
Description |
Area No. |
Population Intake |
Contributions
among D1, D8, D10 and extended P2 |
A21 |
Planned
Residential, R2 |
72 |
2000-2004 |
D1, D8 |
A24 |
Planned
Residential, R2 |
72 |
2000-2004 |
D8 |
A25 |
Planned
School |
72 |
2000-2004* |
D8 |
A26 |
Planned
School |
72 |
2000-2004* |
Extended P2 |
A29 |
Planned
Residential |
65B |
2005 |
D1 |
A30 |
Planned
School |
65C |
2006* |
D1, D10 |
A31 |
Planned
Residential, R1 |
51 |
2000 |
D1 |
A37 |
Planned
Residential |
85 |
2005-2006* |
D10 |
A39 |
Planned
Film Studio |
106 |
2003* |
D10 |
A43 |
Planned
Residential |
73 |
2002 |
D8 |
A44 |
Planned
Residential |
74 |
2006 |
D8 |
A45 |
Planned
Residential |
55A |
2002 |
D1 |
A46 |
Existing
Soccer Pitch |
77 |
- |
D10 |
A48 |
Planned
Residential |
74 |
2006 |
Extended P2 |
A49 |
Planned
Residential |
57B |
2002 |
Extended P2 |
* Represents the commissioning date
Operation
Phase
Table 3.6 Description of Air Sensitive Receivers
(ASRs) during Operation Phase
ASR ID |
Description |
Area No. |
Population Intake |
Horizontal
distance from the kerb of its closest road (m) |
Assess-ment
1 |
Assess-ment
2 |
A07 |
Possible
future development to the south of Road D1 |
N/A |
N/A |
97 |
Ö |
´ |
A10 |
35 |
Ö |
´ |
|||
A11 |
23 |
Ö |
´ |
|||
A12 |
70 |
Ö |
´ |
|||
A13 |
167 |
Ö |
´ |
|||
A14 |
53 |
Ö |
´ |
|||
A21 |
Planned
Residential, R2 |
72 |
2000-2004 |
20 |
Ö |
Ö |
A22 |
Planned
Residential, R1 |
67B |
2007 |
23 |
Ö |
Ö |
A23 |
Planned
Residential, R1 |
65D |
2008 |
16 |
Ö |
Ö |
A24 |
Planned
Residential, R2 |
72 |
2000-2004 |
60 |
Ö |
Ö |
A25 |
Planned
School |
72 |
2000-2004* |
15 |
Ö |
Ö |
A26 |
Planned
School |
72 |
2000-2004* |
23 |
Ö |
Ö |
A29 |
Planned
Residential |
65B |
2005 |
53 |
Ö |
Ö |
A30 |
Planned School |
65C |
2006* |
11 |
Ö |
Ö |
A31 |
Planned
Residential, R1 |
51 |
2000 |
180 |
Ö |
Ö |
A37 |
Planned
Residential |
85 |
2005-2006* |
23 |
Ö |
Ö |
A39 |
Planned
Film Studio |
106 |
2003* |
71 |
Ö |
Ö |
A42 |
Planned
Residential |
86 |
2004-2012 |
4 |
Ö |
Ö |
A43 |
Planned
Residential |
73 |
2002 |
14 |
Ö |
Ö |
A44 |
Planned
Residential |
74 |
2006 |
23 |
Ö |
Ö |
A45 |
Planned
Residential |
55A |
2002 |
15 |
Ö |
Ö |
A46 |
Existing
Soccer Pitch |
77 |
- |
56 |
Ö |
Ö |
A47 |
Planned
School |
67 |
2007 |
26 |
Ö |
Ö |
A48 |
Planned
Residential |
74 |
2006 |
32 |
Ö |
Ö |
A49 |
Planned
Residential |
57B |
2002 |
60 |
Ö |
Ö |
* Represents the
commissioning date
Construction Phase
·
Roadworks
for Road D1
·
Roadworks
for Road D8
·
Roadworks
and bridge foundations for Town Centre Link (Road D10)
·
Roadworks
for extended Road P2
·
Construction
activities for Cross Bay Link (Road D9)
·
Site
formation work for possible future development of Pak Shing Kok (Area 78)
·
Possible
future development to the south of Road D1 and the associated roads and drains
in the development
·
Water
supply infrastructure
·
Construction
activities for Area 86
·
Construction
activities in Area 65D and Area 67
·
Minor
road junction improvement works at the junctions of Road D9 / Wan Po Road, Road
D10 / Wan Po Road, Road D6 / Wan Po Road, and road junctions along D1, D4, D8
and P2
Table 3.7 Dust Emission Factors used in this Assessment
Activities |
References (AP-42, 5th Edition) |
General construction activities |
2,690
kg/hectare/month (Section 13.2.3) |
Wind erosion of open site |
850
kg/hectare/year (Table 11.9.4) |
Operation Phase
Vehicle Emissions
·
Roads
D1, D4, D6, D8, D9 and D10
·
Roads
P1, P2, Wan Po Road, Chiu Shun Road, Po Ning Road and Hang Hau Road
·
Local
roads in and around Areas 55, 56, 57, 65, 66, 67, 72 and 74
·
Local
roads in possible further development to the south of Road D1
Table 3.8 Emission Factors for Year 2011 for Different Vehicle Category
Pollutant |
Emission Factors (gm/km) |
||||
|
Bus |
HGV |
LGV |
Private Car |
Taxi |
NOx |
6.80 |
3.84 |
1.23 |
0.71 |
0.73 |
RSP |
0.69 |
0.53 |
0.11 |
0.03 |
0.01 |
·
Wind
speed : 1 m/s
·
Wind
direction : worst case
·
Wind
variability : 18° (day time) or 6° (night time)
·
Stability
class : D (day time) or F (night time)
·
Surface
roughness : 1 m
·
Mixing
height : 500 m
Air Quality
inside Deckovers of Road D1 for Assessment 1
Construction phase
Table 3.9 Predicted Cumulative TSP Concentrations at the Representative ASRs in Year 2005 (Unmitigated)
|
TSP Concentration (mgm-3)* |
|||
ASRs |
Receiver height = 1.5m |
Receiver height = 10m |
||
|
1-hr Average |
24-hr Average |
1-hr Average |
24-hr Average |
A21 |
1230 |
583 |
688 |
333 |
A24 |
890 |
399 |
698 |
331 |
A25 |
930 |
421 |
753 |
358 |
A26 |
1508 |
696 |
769 |
397 |
A29 |
640 |
286 |
557 |
276 |
A30 |
1192 |
564 |
737 |
412 |
A31 |
751 |
293 |
635 |
274 |
A37 |
1028 |
420 |
476 |
293 |
A39 |
760 |
342 |
501 |
287 |
A43 |
806 |
385 |
702 |
330 |
A44 |
822 |
379 |
706 |
336 |
A45 |
527 |
243 |
479 |
241 |
A46 |
885 |
327 |
589 |
263 |
A48 |
1168 |
503 |
747 |
377 |
A49 |
1178 |
480 |
684 |
350 |
Value in bold type indicates
that the TSP concentration exceeds the HKAQO or the guideline level of 500 mgm-3.
* Background TSP
concentration of 80 mgm-3
is included.
operation phase
Assessment 1
– Worst case situation (with possible further development)
Vehicle Emissions
Table 3.10 Predicted 1-hour Average NO2,
24-hour average NO2 and 24-hour Average RSP Concentrations at the
Representative ASRs (Assessment 1)
|
1-hour Average |
24-hour Average |
24-hour Average |
|
|||||||
ASRs |
NO2 Concentration (mgm-3)* |
NO2 Concentration (mgm-3)* |
RSP Concentration (mgm-3)* |
|
|||||||
|
|
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
||||
|
|
= 1.5m |
= 10m |
= 1.5m |
= 10m |
= 1.5m |
= 10m |
||||
|
A07 |
113 |
108 |
75 |
73 |
68 |
66 |
||||
|
A10 |
194 |
128 |
108 |
81 |
83 |
69 |
||||
|
A11 |
130 |
118 |
82 |
77 |
71 |
68 |
||||
|
A12 |
111 |
97 |
74 |
69 |
67 |
64 |
||||
|
A13 |
93 |
87 |
67 |
65 |
64 |
62 |
||||
|
A14 |
112 |
105 |
75 |
72 |
67 |
66 |
||||
|
A21 |
170 |
149 |
98 |
90 |
79 |
74 |
||||
|
A22 |
124 |
115 |
80 |
76 |
70 |
67 |
||||
|
A23 |
157 |
124 |
93 |
80 |
76 |
69 |
||||
|
A24 |
124 |
119 |
80 |
78 |
70 |
68 |
||||
|
A25 |
109 |
104 |
73 |
72 |
67 |
66 |
||||
|
A26 |
143 |
138 |
87 |
85 |
74 |
73 |
||||
|
A29 |
147 |
127 |
89 |
81 |
74 |
70 |
||||
|
A30 |
105 |
92 |
72 |
67 |
65 |
63 |
||||
|
A31 |
84 |
83 |
64 |
63 |
62 |
62 |
||||
|
A37 |
107 |
97 |
73 |
69 |
67 |
65 |
||||
|
A39 |
80 |
79 |
62 |
62 |
62 |
61 |
||||
|
A42 |
96 |
82 |
68 |
63 |
64 |
61 |
||||
|
A43 |
147 |
120 |
89 |
78 |
74 |
68 |
||||
|
A44 |
111 |
103 |
74 |
71 |
67 |
66 |
||||
|
A45 |
153 |
102 |
91 |
71 |
75 |
65 |
||||
|
A46 |
88 |
81 |
65 |
62 |
62 |
61 |
||||
|
A47 |
156 |
143 |
92 |
87 |
77 |
74 |
||||
|
A48 |
152 |
126 |
91 |
80 |
75 |
70 |
||||
|
A49 |
164 |
144 |
96 |
88 |
77 |
73 |
||||
* Background NO2 concentration of 50 mgm-3 and RSP
concentration of 55 mgm-3
are included.
Air Quality inside Deckover
Table 3.11 Predicted Maximum NO2 Concentrations inside the Two Sections of the Deckover
Deckover |
Maximum NO2
Concentration (mgm-3)* |
|
|
Normal Condition |
Worst Condition |
Section of 190m |
430 |
477 |
Section of 115m |
295 |
325 |
* Background concentration is
included.
Assessment 2
– Committed development
Vehicle Emissions
Table 3.12 Predicted 1-hour Average NO2, 24-hour average NO2 and 24-hour Average RSP Concentrations at the Representative ASRs (Assessment 2)
|
1-hour Average |
24-hour Average |
24-hour Average |
|
|||||||
ASRs |
NO2 Concentration (mgm-3)* |
NO2 Concentration (mgm-3)* |
RSP Concentration (mgm-3)* |
|
|||||||
|
|
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
Receiver
height |
||||
|
|
= 1.5m |
= 10m |
= 1.5m |
= 10m |
= 1.5m |
= 10m |
||||
|
A21 |
164 |
142 |
95 |
87 |
78 |
73 |
||||
|
A22 |
154 |
117 |
92 |
77 |
76 |
68 |
||||
|
A23 |
134 |
106 |
84 |
73 |
72 |
66 |
||||
|
A24 |
119 |
114 |
78 |
76 |
69 |
68 |
||||
|
A25 |
109 |
104 |
73 |
72 |
67 |
66 |
||||
|
A26 |
137 |
132 |
85 |
83 |
73 |
72 |
||||
|
A29 |
147 |
127 |
89 |
81 |
74 |
70 |
||||
|
A30 |
105 |
92 |
72 |
67 |
65 |
63 |
||||
|
A31 |
84 |
83 |
64 |
63 |
62 |
62 |
||||
|
A37 |
107 |
97 |
73 |
69 |
67 |
65 |
||||
|
A39 |
80 |
79 |
62 |
62 |
62 |
61 |
||||
|
A42 |
89 |
90 |
66 |
66 |
63 |
63 |
||||
|
A43 |
144 |
118 |
88 |
77 |
73 |
68 |
||||
|
A44 |
111 |
103 |
74 |
71 |
67 |
66 |
||||
|
A45 |
153 |
102 |
91 |
71 |
75 |
65 |
||||
|
A46 |
88 |
81 |
65 |
62 |
62 |
61 |
||||
|
A47 |
144 |
132 |
88 |
83 |
74 |
72 |
||||
|
A48 |
150 |
122 |
90 |
79 |
75 |
70 |
||||
|
A49 |
163 |
142 |
95 |
87 |
77 |
73 |
||||
* Background NO2 concentration of 50 mgm-3 and RSP
concentration of 55 mgm-3
are included.
CONSTRUCTION PHASE
·
use
of regular watering to reduce dust emissions from exposed site surfaces and
unpaved roads, at least twice daily with complete coverage, particularly during
dry weather;
·
use
of frequent watering for particularly dusty static construction areas and areas
close to air quality sensitive receivers;
·
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 should shall be applied
to aggregate fines;
·
open
stockpiles shouldall be avoided or covered. Where possible, prevent placing dusty
material storage piles near air quality sensitive receivers;
·
provision
of barriers, which may be the temporary noise barrier, between the site and
nearby air quality sensitive receivers to act as dust barriers;
·
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, combined with cleaning of public roads where necessary;
·
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. Eight kilometres per hour is the recommended limit;
·
where
feasible, routing of vehicles and positioning of construction plant should
shall be
at the maximum possible distance from air quality sensitive receivers;
·
instigation
of an environmental monitoring and auditing program to monitor the construction
process in order to enforce controls and modify methods of work if dusty
conditions arise; and
·
good
site practices.
Table 3.13 Predicted TSP Concentrations at the Representative ASRs in Year 2005 (Mitigated)
|
TSP Concentration (mgm-3)* |
|||
ASRs |
Receiver height = 1.5m |
Receiver height = 10m |
||
|
1-hr Average |
24-hr Average |
1-hr Average |
24-hr Average |
A21 |
367 |
206 |
232 |
143 |
A24 |
282 |
160 |
235 |
143 |
A25 |
293 |
165 |
248 |
149 |
A26 |
437 |
234 |
252 |
159 |
A29 |
220 |
131 |
199 |
129 |
A30 |
358 |
201 |
244 |
163 |
A31 |
248 |
133 |
219 |
129 |
A37 |
317 |
165 |
179 |
133 |
A39 |
250 |
145 |
185 |
132 |
A43 |
262 |
156 |
235 |
143 |
A44 |
265 |
155 |
237 |
144 |
A45 |
192 |
121 |
180 |
120 |
A46 |
281 |
142 |
207 |
126 |
A48 |
352 |
186 |
247 |
154 |
A49 |
355 |
180 |
231 |
148 |
* Background TSP
concentration of 80 mgm-3
is included.
operation phase
Assessment 1
– Worst case situation (with possible further development)
Vehicle Emissions
Air Quality inside Deckover
Assessment 2
– Committed development
Vehicle Emissions
construction phase
Operation phase
[1] MTR Tseung Kwan O Line Tseung Kwan O Area 86 Comprehensive Development Area Submission under Section 16/4A Town Planning Ordinance Environmental Assessment, January 1999
[2] Ohashi H. and T. Koso, Longitudinal
Diffusion of Exhaust Pollutants in Two-way Automobile Tunnels, International
Symposium on the Aerodynamics & Ventilation of Vehicle Tunnels, 1995