Project Profile
|
Rev |
Date |
Originator |
Checker |
Approver |
Description |
|
A |
9/07/03 |
Env Team |
AWZ |
- |
Draft |
|
|
|
|
|
|
|
Project Profile
Mott Connell Ltd
40th floor, Hopewell Centre
183 Queen’s Road East
Wanchai
Hong Kong
Tel: 852 2828 5757
Fax: 852 2828 1823
awatker@mottconnell.com.hk
Project Profile
|
Rev |
Date |
Originator |
Checker |
Approver |
Description |
|
A |
9/07/03 |
Env Team |
AWZ |
- |
Draft |
|
|
|
|
|
|
|
E.1 Background
The Diversion of the Ngong Ping Stream, referred to
as the Project, has been identified in the developed design stage, subsequent
to the issue of the Environmental Impact Assessment (EIA) (Study Brief No.
ESB-068/2001) for the Tung Chung Cable Car Project. The Project comprises the
diversion, around the proposed Ngong Ping Cable Car Terminal and Theme Village,
of a section of the existing Ngong Ping Stream (which drains into the Water
Gathering Ground and collects septic tank overflow from the nearby houses) and
a tributary. This constitutes the diversion of approximately 390m of the
existing stream channel, and approximately 80m of the tributary ditch. The
location of the Ngong Ping Stream is shown in Figure 1.1.
Prior to identifying the need for the Project,
serious consideration was given to the alternative of retaining the stream in
its existing location, as this could have been, in the right circumstances, a
feature within the developed site. However a range of engineering statutory and
environmental health issues conspire, in the actual circumstances of the site,
to make this infeasible. The Project is therefore concluded to be necessary to
address the various issues and to provide the space necessary to accommodate
the architectural, planning and engineering features required for a world class
and commercially viable tourist attraction. The Project will also alleviate
potential flooding and water quality issues at Ngong Ping.
The Cable Car Terminal site has previously been
subject to an EIA under Section 5(7) of the Environmental Impact Assessment
Ordinance (EIAO) while an Environmental Assessment has been prepared for the
Theme Village under Section 16 of the Town Planning Ordinance (Cap. 131). The
Project is a Designated Project under the EIAO and is subject to a direct
application for an Environmental Permit.
It is proposed that the stream at Ngong Ping will
be diverted upstream of the Theme Village.
The proposed diverted stream is parallel to the northern boundary of the
site and rejoins the existing watercourse immediately downstream of the
proposed Terminal within the Country Park.
The length of the proposed stream is shorter than the section of
existing stream to be replaced (305m compared to approximately 390m). The
proposed ditch to the west of the site is approximately 80m and replaces an
existing ditch of approximately the same length. The location of the proposed
stream diversion is shown in Figure 1.3.
The design proposal includes localised meanders
within the channels through incorporation of riffles and boulders to create a
meandering low flow channel, within the main channel. The boulders will be set on alternate sides of the channel and
will serve as current deflectors which will allow gravel and sediment to
re-establish within the channel and provides habitat for fauna and flora, while
allowing efficient maintenance of the reserve.
Compensation measures and fauna relocations are also proposed along the
cable car alignment.
The proposed stream sections are designed to merge
into the existing stream course and environment with minimal visual and
environmental impacts. Where possible, excavated rock shall be used to form the
rip-rap and gabions to minimise the extent of materials required and disposed
of and to maintain the natural geological environment. Similarly, it is
proposed that the rocks lining the existing stream will be re-utilized. A
gabion channel is proposed to encourage vegetation growth for blending into the
existing rural/ natural area.
E.3 Community Consultation
The Project has been developed through consultation
with stakeholders including the Green Groups (who have been consulted regularly
since before the start of the EIA process) and local community and through
Value Engineering. Various design methods used overseas have been considered,
however the particular circumstances of Hong Kong have required special
consideration within the design. This proposed construction is subject to
detailed design and will need to be approved by Drainage Services Department. The land take will need to be agreed with
the relevant Government Departments and Country and Marine Parks Board before
the construction details can finally be confirmed.
Further consultation with Green Groups is
anticipated. A specific feature of this consultation will be to identify
measures for detailing the diversion in order to enhance its ecological
attractiveness.
Various diversion schemes were assessed and
compared. Engineering and architectural evaluation has been undertaken and the
options were selected based on engineering feasibility, land take and
environmental impact. The following
three options were considered in detail:
Option 1: Maintain
a Route through the Theme Village Complex;
Option
2: Divert the Stream around the
Northern Boundary of the Theme Village Complex; and
Option 3: Divert
the Stream across the Theme Village Complex and PTI.
Taking account of restrictions given in the Outline
Zoning Plan which dictate specific use of particular areas within the Theme
Village as well as requirements from Drainage Services Department to prevent
flooding and those from Water Supplies Department to prevent pollution into the
Water Gathering Ground, Option 1 is not feasible. Option 3 is also not feasible
as this option would not intercept all the local tributaries and ditches, and
had potential to disturb graves in the vicinity.
Consequently, Option 2 was selected, as it is
considered to provide the best solution in overall terms.
The works will be undertaken in three sections from
west to east over a three-month period at the outset of the works at Ngong Ping
so as to minimise the number of construction vehicles and traffic affecting the
surrounding areas.
E.6 Conclusions of the Assessments
Assessments have been carried out to determine the
environmental impacts associated with the Project. The works would generate short term impacts in terms of noise,
ecology, and visual and landscape during construction. These impacts can be
controlled to acceptable levels. Once completed there are significant benefits
to be accrued from the Project including the enhancement of water quality,
reduction in the potential for flooding and enhancement in terms of ecological
and habitat resources.
Air Quality
: Construction works have been assessed, and the short term impacts associated
with fugitive dusts will easily comply with the Air Quality Objectives even
without mitigation measures being applied.
Noise :
Noise assessments concluded that due to the need for rock breaking in some
sections where the rockhead is close to the surface, some sensitive receivers
may experience noise levels in excess of the acceptable day time criteria of
75dB(A) in situation where no mitigation measures are applied. The application
of standard mitigation measures, such as quiet plant and the use of a mobile
noise barrier, will ensure the noise levels are reduced to acceptable levels.
Waste
:Reduction of waste and the re-use of materials in-situ is the design
requirement to minimise the need for off-site disposal of material as far as
practical.
Water :
During construction some potential water quality impacts could arise. These
will be controlled and are considered to be acceptable on the basis of the
extension of the Environmental Code of Practice for the Tung Chung Cable Car
Project to encompass this project. Once operational the water quality benefits
include the enhancement of flows, reduction in stagnation and the added benefit
of the elimination of pollution load from the septic tank overflow once the DSD
Ngong Ping Sewage Treatment Plant and Sewerage Scheme is fully implemented.
Ecology
: The realignment of the stream course will result in the loss of natural
topography, flora and fauna during construction. Compensatory planting and
fauna relocation are required to mitigate these impacts. Once operational the
benefits to be accrued are the enhancement of the local habitats due to the
incorporation of gabions, riffles and rip-rap allowing areas for colonisation
of a range of species.
Landscape and Visual :
Changes to the topography will create some visual intrusion unless the design
is sensitively carried out. The stream course design therefore focuses upon the
maximisation of plant and wildlife re-colonisation and the creation of a
landscape feature which is an extension and integral part of the Theme Village
rather than a separate item.
Cultural Heritage :
Three shrines are located in the vicinity of the works. Two shrines shall
require relocation. Village and monastery representatives have given
preliminary agreement. The third shrines may be retained.
Summary : The impacts
associated with the construction and operation of the stream course diversion
are acceptable and in overall terms will provide benefits to the area.
The Diversion
of the Ngong Ping Stream, referred to as the Project, has been identified in
the developed design stage, subsequent to the issue of the Environmental Impact
Assessment (EIA) (Study Brief No. ESB-068/2001) for the Tung Chung Cable Car
Project. The Project comprises the diversion, around the proposed Ngong Ping
Cable Car Terminal and Theme Village, of a section of the existing Ngong Ping
Stream (which drains into the Water Gathering Ground and collects septic tank
overflow from the nearby houses) and a tributary around the proposed Ngong Ping
Cable Car Terminal and Theme Village. This constitutes the diversion of
approximately 390m of the existing stream channel, and approximately 80m of the
tributary ditch. The location of the Ngong Ping Stream is shown in Figure 1.1.
Prior to identifying the need for the Project,
serious consideration was given to the alternative of retaining the stream in
its existing location, as this could have been, in the right circumstances, a
feature within the developed site. However a range of engineering statutory and
environmental health issues conspire, in the actual circumstances of the site,
to make this infeasible. The Project is therefore concluded to be necessary to
address the various issues and to provide the space necessary to accommodate
the architectural, planning and engineering features required for a world class
and commercially viable tourist attraction. The Project will also alleviate
potential flooding, water quality and environmental health issues in local
villages and in the vicinity of the proposed Cable Car developments at Ngong
Ping.
The Cable Car
Terminal site has previously been subject to an EIA under Section 5(7) of the
Environmental Impact Assessment Ordinance (EIAO) while an Environmental
Assessment has been prepared for the Theme Village under Section 16 of the Town
Planning Ordinance (Cap. 131).
E.2 Scale
of the Project
It is proposed
that the stream at Ngong Ping will be diverted upstream of the Theme
Village. The proposed diverted stream
is parallel to the northern site boundary of the site and rejoins the existing
watercourse immediately downstream of the proposed Terminal within the Country
Park. The length of the proposed stream
is shorter than the section of existing stream to be replaced (305m compared to
approximately 390m). The proposed ditch to the west of the site is
approximately 80m and replaces an existing ditch of approximately the same
length. The location of the proposed stream diversion is shown in Figure 1.3.
The design proposal includes localised meanders
within the channels through incorporation of riffles and boulders to create a
meandering low flow channel, within the main channel. The boulders will be set on alternate sides of the channel and
will serve as current deflectors which will allow gravel and sediment to
re-establish within the channel and provides habitat for fauna and flora, while
allowing efficient maintenance of the reserve.
Compensation measures and fauna relocations are also proposed along the
Cable Car alignment. The design of the stream will be subject to approval by
Drainage Services Department.
The proposed
stream sections are designed to merge into the existing stream course and
environment with minimal visual and environmental impacts. Where possible,
excavated rock shall be used to form the rip-rap and gabions to minimise the
extent of materials required and disposed of and to maintain the natural
geological environment. Similarly, it is proposed that the rocks lining the
existing stream will be re-utilized. A gabion channel is proposed to encourage
vegetation growth for blending into the existing rural/ natural area.
E.3 Community Consultation
The Project has
been developed through consultation with stakeholders including the Green
Groups (who have been consulted regularly since before the start of the EIA
process) and local community and through Value Engineering. Various design
methods used overseas have been considered, however the particular
circumstances of Hong Kong have required special consideration within the
design. This proposed construction is subject to detailed design and will need
to be approved by DSD. The land take
will need to be agreed with the relevant Government Departments and Country and
Marine Parks Board before the construction details can finally be confirmed.
Further consultation with Green Groups is
anticipated. A specific feature of this consultation will be to identify
measures for detailing the diversion in order to enhance its ecological
attractiveness.
E.4 Options
Considered
Various
diversion schemes were assessed and compared. Engineering and architectural
evaluation has been undertaken and the options were selected based on
engineering feasibility, land take and environmental impact. The following three options were considered
in detail:
Option 1: Maintain a Route through the Theme Village
Complex;
Option 2: Divert the Stream around the Northern Boundary
of the Theme Village Complex; and
Option 3: Divert the Stream across the Theme Village
Complex and PTI.
The Cable Car
Theme Village Complex is subject to a number of design restrictions. The
Outline Zoning Plan gives specific planning and uses restrictions for
particular areas within the Theme Village Complex, and thereby dictates the
organisation and positioning of the buildings.
Drainage Services Department requires the stream capacity to accommodate
storm events to prevent flooding. The
Water Supplies Department
requires prevention of pollution from the Theme Village into the watercourse
and the Water Gathering Grounds. Other requirements relate to visual amenity
and environmental health concerns over poor water quality prevalent during the
dry season.
Option 2 was
selected, as it is considered to provide the best solution in overall terms.
E.5 Implementation
Strategy
The works will
be undertaken in three sections from west to east over a three-month period at
the outset of the works at Ngong Ping so as to minimise the number of
construction vehicles and traffic affecting the surrounding areas.
E.6 Conclusions of the Assessments
Assessments
have been carried out to determine the environmental impacts associated with
the Project. The works would generate short-term impacts in
terms of noise, ecology, and visual and landscape during construction. These
impacts can be controlled to acceptable levels. Once completed there are
significant benefits to be accrued from the Project including the enhancement
of water quality, reduction in the potential for flooding and enhancement in
terms of ecological and habitat resources.
Air Quality : Construction works have been assessed, and the
short term impacts associated with fugitive dusts will easily comply with the
Air Quality Objectives even without mitigation measures being applied.
Noise : Noise assessments concluded that due to the need
for rock breaking in some sections where the rockhead is close to the surface,
some sensitive receivers may experience noise levels in excess of the
acceptable day time criteria of 75dB(A) in situation where no mitigation
measures are applied. The application of standard mitigation measures, such as
quiet plant and the use of a mobile noise barrier, will ensure the noise levels
are reduced to acceptable levels.
Waste : Reduction of waste and the re-use of materials
in-situ is the design requirement to minimise the need for off-site disposal of
material as far as practical.
Water : During construction some potential water quality
impacts could arise. These will be controlled and are considered to be
acceptable on the basis of the extension of the Environmental Code of Practice
for the Tung Chung Cable Car Project to encompass this project. Once
operational the water quality benefits include the enhancement of flows,
reduction in stagnation and the added benefit of the elimination of pollution
load from the septic tank overflow once the DSD Ngong Ping Sewage Treatment
Plant and Sewerage Scheme is fully implemented.
Ecology : The realignment of the stream course will result
in the loss of natural topography, flora and fauna during construction.
Compensatory planting and fauna relocation are required to mitigate these
impacts. Once operational the benefits to be accrued are the enhancement of the
local habitats due to the incorporation of gabions, riffles and rip-rap
allowing areas for colonisation of a range of species.
Landscape and Visual : Changes to the topography will create some
visual intrusion unless the design is sensitively carried out. The stream
course design therefore focuses upon the maximisation of plant and wildlife
re-colonisation and the creation of a landscape feature which is an extension
and integral part of the Theme Village rather than a separate item.
Cultural Heritage : Three shrines are located in the vicinity of the
works. Two shrines shall require relocation. Village and Monastery
Representatives have given preliminary agreement. The third shrine may be
retained.
Summary : The impacts associated with the construction and
operation of the stream course diversion are acceptable and in overall terms
will provide benefits to the area.
List
of Contents Page
Chapters
1.1 Project Title 1
1.2 Purpose and Nature of the Project 1
1.3 Name of Project Proponent 1
1.4 Contact Persons 1
1.5 Location of the Project 1
1.6 Scale of the Project 12
1.7 Site History and Existing Condition 3
1.7.1 Stream Formation 3
1.7.2 Water Quality 34
1.7.3 Flooding 34
1.7.4 Environmental 45
1.8 Options Considered 45
1.8.1 Option 1 - Maintain a Route through the
Theme Village 45
1.8.2 Option 2 - Divert the Stream around the
Northern Boundary of the Theme Village 68
1.8.3 Option 3 - Divert the Stream across the
Theme Village and Proposed PTI 79
1.8.4 Conclusion 79
1.9 Number and Types of Designated Projects
to be Covered by the Project Profile 79
2 OUTLINE
OF PLANNING AND IMPLEMENTATION PROGRAMME 810
2.1 Planning 810
2.2 Implementation Strategy 810
2.3 Materials Strategy 810
2.4 Public Relations Strategy 810
2.5 Project Interfaces 811
3 MAJOR
ELEMENTS OF THE SURROUNDING ENVIRONMENT 1012
3.1 Air 1012
3.1.1 Existing Environment 1012
3.1.2 Sensitive Receivers 1012
3.2 Noise 1012
3.2.1 Existing Environment 1012
3.2.2 Sensitive Receivers 1012
3.3 Water 1012
3.3.1 Existing Environment 1012
3.3.2 Sensitive Receivers 1013
3.4 Ecology 1013
3.4.1 Existing Environment 1113
3.4.2 Sensitive Receivers 1620
3.5 Landscape and Visual 1620
3.5.1 Existing Resources 1621
3.5.2 Sensitive Receivers 1721
3.6 Cultural Heritage 1722
3.6.1 Existing Environment 1722
3.6.2 Sensitive Receivers 1822
3.7 Hazard to Life 1823
4 POTENTIAL ENVIRONMENTAL IMPACTS 1924
4.1 Introduction 1924
4.2 Air Quality 1924
4.2.1 Introduction 1924
4.2.2 Potential Sources of Impact 1924
4.2.3 Prediction of Potential Impacts 2025
4.2.4 Evaluation of Impacts 2026
4.2.5 Cumulative Impacts 2126
4.3 Noise 2126
4.3.1 Introduction 2126
4.3.2 Potential Sources of Impact 2127
4.3.3 Prediction of Potential Impacts 2228
4.3.4 Evaluation of Impacts 2228
4.4 Waste 2228
4.4.1 Introduction 2228
4.4.2 Potential Sources of Impact 2229
4.4.3 Prediction of Potential Impacts 2430
4.4.4 Evaluation of Impacts 2430
4.5 Water 2532
4.5.1 Introduction 2532
4.5.2 Potential Sources of Impact 2532
4.5.3 Evaluation of Impacts 2532
4.6 Ecology 2633
4.6.1 Introduction 2633
4.6.2 Potential Sources of Impact 2633
4.6.3 Evaluation of Impacts 2633
4.7 Landscape and Visual 2836
4.7.1 Introduction 2836
4.7.2 Potential Sources of Impact 2836
4.7.3 Prediction of Impacts 2836
4.7.4 Evaluation of Impacts 2938
4.8 Archaeology and Cultural Heritage 3039
4.8.1 Introduction 3039
4.8.2 Potential Sources of Impact 3039
4.8.3 Prediction of Potential Impacts 3140
4.8.4 Evaluation of Impacts 3140
5.1 Air 3241
5.1.1 Recommended Mitigation Measures during
Construction 3241
5.1.2 Residual Impacts 3241
5.1.3 Conclusions 3241
5.2 Noise 3242
5.2.1 Recommended Noise Mitigation Measures
during Construction 3242
5.2.2 Assessment of Mitigated Impacts 3444
5.2.3 Residual Impacts 3444
5.2.4 Conclusions 3544
5.3 Waste Management Systems and Practices 3645
5.3.1 Recommended Waste Management Systems and
Practices 3645
5.3.2 Control/Mitigation Measures 3645
5.4 Water 3747
5.4.1 Recommended Mitigation Measures during
Construction / Operation 3747
5.4.2 Residual Impacts 4050
5.4.3 Conclusions 4050
5.5 Ecology 4051
5.5.1 Recommended Mitigation Measures during
Construction / Operation 4051
5.5.2 Residual Impacts 4252
5.5.3 Compensation 4253
5.5.4 Conclusions 4253
5.6 Landscape and Visual 4253
5.6.1 Recommended Mitigation Measures during
Construction / Operation 4253
5.6.2 Stream Landscape Design 4354
5.6.3 Conclusion 4657
5.7 Cultural Heritage 4657
5.7.1 Recommended Mitigation Measures during
Construction / Operation 4657
5.7.2 Residual Impacts 4657
5.7.3 Conclusions 4657
5.8 Community Consultation 4657
6 ENVIRONMENTAL MONITORING AND AUDIT 4859
6.1 Introduction 4859
6.2 Waste 4859
6.3 Water Quality 4859
6.4 Ecology 4859
6.5 Landscape and Visual 4859
7 PREVIOUSLY APPROVED EIA REPORTS 4960
8 CONCULSIONS 5061
8.1 Air 5061
8.2 Noise 5061
8.3 Water 5061
8.4 Ecology 5061
8.5 Landscape and Visual 5062
8.6 Cultural Heritage 5162
9 REFERENCES 5263
1 BASIC
INFORMATION 710
1.1 Project
Title 710
1.2 Purpose
and Nature of the Project 710
1.3 Name
of Project Proponent 710
1.4 Contact
Persons 710
1.5 Location
of the Project 710
1.6 Scale
of the Project 711
1.7 Site
History and Existing Condition 912
1.7.1 Stream
Formation 912
1.7.2 Water
Quality 1013
1.7.3 Flooding 1013
1.7.4 Environmental 1114
1.8 Options
Considered 1114
1.8.1 Option
1 - Maintain a Route through the Theme Village 1114
1.8.2 Option
2 - Divert the Stream around the Northern Boundary of the Theme Village 1417
1.8.3 Option
3 - Divert the Stream across the Theme Village and Proposed PTI 1518
1.8.4 Conclusion 1518
1.9 Number
and Types of Designated Projects to be Covered by the Project Profile 1518
2 OUTLINE
OF PLANNING AND IMPLEMENTATION PROGRAMME 1619
2.2 Implementation
Strategy 1619
2.3 Materials
Strategy 1619
2.4 Public
Relations Strategy 1619
2.5 Project
Interfaces 1720
3 MAJOR
ELEMENTS OF THE SURROUNDING ENVIRONMENT 1821
3.1 Air 1821
3.1.1 Existing
Environment 1821
3.1.2 Sensitive
Receivers 1821
3.2 Noise 1821
3.2.1 Existing
Environment 1821
3.2.2 Sensitive
Receivers 1821
3.3 Water 1821
3.3.1 Existing
Environment 1821
3.3.2 Sensitive
Receivers 1922
3.4 Ecology 1922
3.4.1 Existing
Environment 1922
3.4.2 Sensitive
Receivers 2629
3.5 Landscape
and Visual 2630
3.5.1 Existing
Resources 2730
3.5.2 Sensitive
Receivers 2730
3.6 Cultural
Heritage 2831
3.6.1 Existing
Environment 2831
3.6.2 Sensitive
Receivers 2832
3.7 Hazard
to Life 2932
4 POTENTIAL
ENVIRONMENTAL IMPACTS 3033
4.1 Introduction 3033
4.2 Air
Quality 3033
4.2.1 Introduction 3033
4.2.2 Potential
Sources of Impact 3033
4.2.3 Prediction
of Potential Impacts 3134
4.2.4 Evaluation
of Impacts 3235
4.2.5 Cumulative
Impacts 3235
4.3 Noise 3235
4.3.1 Introduction 3235
4.3.2 Potential
Sources of Impact 3335
4.3.3 Prediction
of Potential Impacts 3437
4.3.4 Evaluation
of Impacts 3437
4.4 Waste 3437
4.4.1 Introduction 3437
4.4.2 Potential
Sources of Impact 3537
4.4.3 Prediction
of Potential Impacts 3639
4.4.4 Evaluation
of Impacts 3639
4.5 Water 3840
4.5.1 Introduction 3840
4.5.2 Potential
Sources of Impact 3841
4.5.3 Evaluation
of Impacts 3841
4.6 Ecology 3941
4.6.1 Introduction 3941
4.6.2 Potential
Sources of Impact 3942
4.6.3 Evaluation
of Impacts 3942
4.7 Landscape
and Visual 4245
4.7.1 Introduction 4245
4.7.2 Potential
Sources of Impact 4245
4.7.3 Prediction
of Impacts 4245
4.7.4 Evaluation
of Impacts 4446
4.8 Archaeology
and Cultural Heritage 4548
4.8.1 Introduction 4548
4.8.2 Potential
Sources of Impact 4548
4.8.3 Prediction
of Potential Impacts 4548
4.8.4 Evaluation
of Impacts 4649
5 ENVIRONMENTAL
PROTECTION MEASURES TO BE INCORPORATED IN THE DESIGN AND ANY FURTHER
ENVIRONMENTAL IMPLICATIONS 4750
5.1 Air 4750
5.1.1 Recommended
Mitigation Measures during Construction 4750
5.1.2 Residual
Impacts 4750
5.1.3 Conclusions 4750
5.2 Noise 4851
5.2.1 Recommended
Noise Mitigation Measures during Construction 4851
5.2.2 Assessment
of Mitigated Impacts 5053
5.2.3 Residual
Impacts 5053
5.2.4 Conclusions 5053
5.3 Waste
Management Systems and Practices 5154
5.3.1 Recommended
Waste Management Systems and Practices 5154
5.3.2 Control/Mitigation
Measures 5154
5.4 Water 5356
5.4.1 Recommended
Mitigation Measures during Construction / Operation 5356
5.4.2 Residual
Impacts 5659
5.4.3 Conclusions 5659
5.5 Ecology 5760
5.5.1 Recommended
Mitigation Measures during Construction / Operation 5760
5.5.2 Residual
Impacts 5861
5.5.3 Compensation 5962
5.5.4 Conclusions 5962
5.6 Landscape
and Visual 5962
5.6.1 Recommended
Mitigation Measures during Construction / Operation 5962
5.6.2 Stream
Landscape Design 6063
5.6.3 Conclusion 6367
5.7 Cultural
Heritage 6367
5.7.1 Recommended
Mitigation Measures during Construction / Operation 6367
5.7.2 Residual
Impacts 6367
5.7.3 Conclusions 6367
5.8 Community
Consultation 6367
6 ENVIRONMENTAL
MONITORING AND AUDIT 6569
6.1 Introduction 6569
6.2 Waste 6569
6.3 Water
Quality 6569
6.4 Ecology 6569
6.5 Landscape
and Visual 6569
7 PREVIOUSLY
APPROVED EIA REPORTS 6670
Appendices
Appendix A Plates
Appendix B Detailed Calculation of Construction Dust Emission Factors
Appendix C Construction Noise Calculations
Appendix D Flora Lists
Appendix E Fauna List
Appendix F Butterfly Food Synergies
Appendix G Flora Compensation Plan
Appendix H Fauna Translocation and Compensation Plan
Appendix I Implementation
Schedule
List of Tables
Table 3.1 Emission Factors for Various Construction
Activities
Table 3.2 Predicted Hourly and Daily TSP Levels
Table 3.3a Plant Inventory (no mitigation measures) with
Rock Breaker
Table 3.3b Plant Inventory (no mitigation measures) without
Rock Breaker
Table 3.4 Noise Impacts at Receiver (no mitigation
measures) Leq30mindB(A)
Table 3.5 Summary of Landscape Impacts (without
mitigation)
Table 3.6 Summary of Visual Impacts
Table
4.1 Location of Representative Air and
Noise Sensitive Receivers
Table
4.2 Number of Trees Transplanted,
Retained and Felled for the Stream Diversion
Table
4.3 Ecology Evaluation of Ngong Ping
Stream to be diverted
Table
4.4 Amphibian Species Recorded at Ngong
Ping Plateau
Table
4.5 Reptile Species Recorded at Ngong
Ping Plateau
Table
4.6 Previous records of mammal species
recorded within/near the Study Area
Table
4.7 Ecologically Sensitive Receivers
Table
5.1 Sound Power Levels for Specific
Silenced PME
Table 5.2a Plant Inventory (using quiet plant) with Rock Breaker
Table 5.2b Plant Inventory (using quiet plant) without
Rock Breaker
Table 5.3a Plant Inventory (Using moveable noise barrier)
with Rock Breaker
Table
5.3b Plant Inventory (Using moveable
noise barrier) without Rock Breaker
Table
5.4 Noise Impact at Receiver (using quiet
plant and noise barrier)
Table
5.5 Indicative Compensatory Plant List
Table
5.6 Summary of Residual Landscape and
Visual Impacts
Table 3.1: Locations of Air and Noise SRs 10121218
Table
3.2: Summary of Ecological Surveys
undertaken by BMT (2002) and Mott Connell (2002 and 2003) of the Study Area 11141420
Table
3.3: Number
of Trees Transplanted, Retained and Felled for the Stream Diversion 13151521
Table
3.4: Evaluation of Plantation at
Ngong Ping 13161622
Table
3.5: Evaluation of Shrubland
Habitat at Ngong Ping 14171723
Table
3.6 Evaluation of Cultivation/
Abandoned Cultivation at Ngong Ping 14171723
Table
3.7 Ecology Evaluation of Ngong
Ping Stream Habitat 15181824
Table
4.1: Major Potential Impacts
during Construction and Operation Associated with the Stream Diversion 19242430
Table
4.2: Emission Factors for Various
Construction Activities 20252531
Table
4.3: Predicted Hourly and Daily
TSP Levels ( mgm-3)
(1) at 1.5m above local ground level 20262632
Table
4.4: Plant Inventory
(No Mitigation Measures) [with Rock Breaker] 21272733
Table
4.5: Plant Inventory (No Mitigation
Measures) [without Rock Breaker] 22272733
Table
4.6: Noise Impacts at Receiver (No
mitigation Measures) - (Leq.30min dB(A)) 22282834
Table
4.7: Ecologically Sensitive
Receivers and Evaluation of Impacts 27343440
Table
4.8: Summary of Landscape Impacts
(without mitigation) 29373743
Table
4.9: Summary of Visual Impacts 29373743
Table
5.1: Sound Power Levels for
Specific Silenced PME 33424248
Table
5.2: Plant Inventory (Using Quiet
Plant) [with Rock Breaker] 33424248
Table
5.3: Plant Inventory (Using Quiet Plant) [without Rock Breaker] 33434349
Table 5.4: Plant
Inventory (Using Movable Noise Barrier)[with Rock Breaker] 34434349
Table
5.5: Plant Inventory (Using Movable Noise
Barrier)[without Rock Breaker] 34444450
Table
5.6: Noise Impacts at Receiver
(Using Quiet Plant and Noise Barriers) - (Leq.30min dB(A)) 34444450
Table
5.7: Summary of Residual Landscape
and Visual Impacts 45555561
Figure 1.1 Location Plan
Figure 1.2 Existing Stream Course
Alignment
Figure 1.3 Proposed Stream Works
Figure 1.4 Ngong
Ping Stream Diversion Cross SectionProposed Stream Cross Sections
Figure 1.5 Ngong Ping Outline Zoning PlanNgong Ping
Stream Diversion Option 1
Figure 1.6 Ngong Ping Stream Diversion Option 3
Figure 34.1 Location of Representative Sensitive
Receivers
Figure 34.2 Habitat
Map of the Ngong Ping Study Area
Figure 4.2 Location for Compensatory Planting: Option 1
Figure 4.3 Location for Compensatory Planting: Option 2
Figure 4.4 Location for Compensatory Planting: Option 3
Figure 5.1 Landscape and Visual Assessment and Mitigation
ProposalsFigure
3.3 Cultural Heritage Sensitive
Receivers
Figure 5.1 Location for Compensatory Planting: Option 1
Figure 5.2 Location for Compensatory Planting: Option 2
Figure 5.3 Location for Compensatory Planting: Option 3
Figure 55.24 Proposed
Landscape Treatment to Stream Course
Figure 5.5 Landscape and Visual
Assessment and Mitigation Proposals
Tung Chung Cable Car Project – Diversion of the Ngong Ping Stream.
The
Project comprises the diversion of a section of the existing Ngong Ping Stream
and a tributary around the proposed Ngong Ping Cable Car Terminal and Theme
Village. This work involves the diversion of approximately 390m of the existing
stream channel, and approximately 680m of a ditch whichditch, which forms a
tributary to the Ngong Ping Stream. The
proposed construction generally comprises a mix of rip-rap and gabions.
The
existing stream drains the surrounding Ngong Ping Catchment and takes septic
tank overflow from nearby houses. The
stream drains into which lies within the Water Gathering Ground drains into the Lantau North Country
Park.
The diversion of the Ngong Ping Stream will provide the space necessary to accommodate the architectural, planning and engineering features required for a world class, and commercially viable, tourist village and attraction. In fact, serious consideration has been given to the alternative of retaining the existing stream, which in other circumstances could have been an attraction within the proposed Theme Village. However, there are a range of issues which have conspired to make this infeasible and lead to the conclusion that diversion of the stream is an essential aspect of the project. The diversion will also alleviate potential flooding, water quality and environmental health issues in the vicinity of the proposed Tung Chung Cable Car Theme Village and Terminal Sites.
MTR Corporation Limited
Dr Glenn H. Frommer
MTR Corporation Limited
MTR Tower Telford Plaza
Kowloon Bay, Hong Kong
Telephone: (852) 2993 2111
Direct Line: (852) 2993 3543
Facsimile: (852) 2993 7743
E-mail: gfrommer@mtr.com.hk
The works are located to the north and west of the proposed Ngong Ping Cable Car Terminal and Theme Village. The location of the Ngong Ping Stream is shown in Figure 1.1. The existing stream, along with its tributaries, passes through the centre of the proposed Tung Chung Cable Car Theme Village and Terminal Site. Figure 1.2 shows the existing stream course alignment and Figure 1.3 shows the proposed stream diversion.
The Cable Car Terminal site has previously been subject to an Environmental Impact Assessment (EIA) under Section 5(7) of the Environmental Impact Assessment Ordinance (EIAO) (Study Brief No. ESB-068/2001) while an Environmental Assessment has been prepared for the Theme Village under Section 16 of the Town Planning Ordinance (cap. 131).
It is proposed that the stream at Ngong Ping will be diverted upstream of the Theme Village Complex. The proposed diverted stream is parallel to the northern site boundary of the site and rejoins the existing watercourse immediately downstream of the proposed Terminal within the Country Park. The length of the proposed stream is shorter than the section of existing stream to be replaced (305m compared to approximately 390m) and has fewer meanders. The proposed ditch to the west of the site is approximately 80m and replaces an existing ditch of approximately the same length. The design proposal includes localised meanders within the channels through incorporation of riffles and boulders to create a meandering low flow channel, within the main channel. The boulders will be set on alternate sides of the channel and will serve as current deflectors which will allow gravel and sediment to re-establish within the channel, and provide a habitat for fauna and flora while allowing efficient maintenance of the reserve. Compensation measures are also proposed along the Cable Car alignment. The design of the stream will be subject to approval by DSD (the authority who will take up the maintenance responsibilities).
The proposed stream sections are designed to merge into the existing stream course and environment with minimal visual and environmental impacts. The proposed construction of the main stream and drainage ditch to the west side is illustrated in Figure 1.4 and comprise:
· A gabion lined stream channel on the upstream and downstream reaches of the main stream comprising berms and riffles to encourage vegetation.
· Gabion mattresses and rip rap or the natural rock will be used to line the stream in the central section according the geological conditions where the natural ground level is higher and deeper cutting is required. Bank support will be provided by gabion baskets.
· Berms and planting reserves have been introduced to assist the establishment of a vegetated environment.
· Rip rap is proposed on the drainage ditch to the west side of the site. The proposed drainage ditch is a diversion of an existing ditch that merges into the main stream, and primarily intercepts the natural runoff to the south-west of the proposed site preventing runoff from entering the Theme Village Complex.
Where suitable, excavated rock shall be used to form the rip-rap and gabions to minimise the extent of materials required and disposed of and to maintain the natural geological conditions. To reduce waste and maintain the natural geology, it is proposed that the rocks lining the existing stream will be utilized. A gabion channel is proposed to encourage vegetation growth for blending into the existing rural/ natural area.
Based on the available site investigation information it is estimated that between chainages 125 and 255m rock will be encountered. Where sound rock is found, the need for erosion and scour protection is considered not to be necessary. It is feasible to use the natural geological conditions to form the stream course, however such an approach would have significant ecological impact.
The proposed construction has been developed through consultation with stakeholders including the Green Groups and through Value Engineering. The current proposals replace the original concepts that comprised a box culvert through the central section of the site and masonry lined channel on the upstream reaches. The box culvert was proposed since it would impact least on the local topography and land take.
Various design methods used overseas have been considered, however the particular circumstances of Hong Kong have required special consideration within the design. These include the prevalence of Dengue fever and hence the aim to avoid stagnant water; the seasonal nature of flows ranging from virtually nothing to high flash floods; and the local environment.
This proposed construction is subject to detailed design and will need to be approved by DSD. The land take will be need to be agreed with the relevant Government Departments and Country and Marine Parks Board before the construction details can finally be confirmed.
The following constraints and considerations have been incorporated into the stream diversion design:
· upstream and downstream invert levels must tie in with existing stream bed levels;
· the western bridge to the columbarium needs to be low enough to provide minimum clearance beneath the cable cars;
· the extent of land affected;
· a consideration in the design of the stream diversion has been the loss of stream length through diversion. In order to minimise this impact, riffles comprising boulders set into the bed of the river will be introduced in order to create a low flow channel with a meander inside the main stream. Whilst additional meanders would be desirable it should be noted that further land-take and maintenance would be required;
· the existing stream lies within a water gathering ground, and therefore one of the catchment management considerations is to ensure that ‘run-off’ to the stream is not reduced. Hydrological calculations estimating the rainfall run-off both before and after construction of the proposed works show this criteria is satisfied;
· the design of the stream must be approved by DSD who will eventually maintain the stream. It is therefore necessary to comply with the well established criteria set down by Government to provide a design that is acceptable for maintenance and access, and that has an acceptable flooding risk; and
· the Outline Zoning Plan requirements for the design of the Terminal and Theme Village need to be observed and any works affecting the stream course must be compatible with these requirements.
The Ngong Ping Stream within the site is shallow and narrow, relative to its upstream catchment size. The existing ground to the side of the stream is natural and serves as a flood path under heavy rainfall conditions.
The stream runs though a steep natural mountainous area downstream of the site. The stream flow is eventually either captured by the Water Supplies Department’s catch waters that drain into Shek Pik Reservoir or conveyed through rural hinterland and discharged to the sea at Sham Wat Wan.
Upstream
of the Project Site, the Ngong Ping Stream runs between the scattered village
buildings, has smoother and more regular surfacing and thus has a relatively
higher drainage capacity. The channelized portion of the upstream section has
smooth surfacing and is slightly steeper. This further increases the drainage
capacity for flood protection in the upstream developments. The drainage capacity of the watercourse is
however limited, as the stream is narrow and the gradient shallow. The existing
flood risks are described below in Section
1.7.23.
The stream at Ngong Ping is seasonal has generally poor water quality, particularly in the dry season (between October and March). The stream has very little flow during the dry season, reducing the potential of using the Ngong Ping Stream as a feature. In addition, the overflow of existing village septic tanks discharge into the stream causing conspicuous pollution and odours during low flow conditions.
DSD plans to construct a Sewage Treatment Plant (STP) to the South West of the site to improve the current conditions at Ngong Ping, which is programmed for completion in time for the commencement of the Cable Car operations. DSD are also undertaking a phased programme of sewer construction to provide connections to the STP. DSD’s Project was subject to an EIA made under Study Brief No. (ESB-074/2001) and the findings have been used in the cumulative impact assessment of the developments at Ngong Ping. In the first phase, the mains sewers will be constructed and it is understood that connections will be provided for the monastery, the public toilets, the new development and some village houses.
In the second phase, which has a current target completion date of 2007, the remaining village connections will be made. It is anticipated that the diverted stream will continue to convey overflow from septic tanks for approximately two years following the commencement of Cable Car operations in 2005. The presence of poor water quality and the odours from the stream is considered unacceptable for a tourist attraction.
As a consequence of the proposed stream diversion, it has provisionally been agreed that DSD will connect sewerage from the dwellings to the north of the stream diversion (refer to Figure 1.3 approximate Chainage 150) into the Theme Village sewerage system in order to advance the sewerage connection programme.
The possibility of using the tertiary treated effluent from the STP to supplement the stream flow during periods of low flow, has been investigated. However any water released from the STP needs to be treated to drinking water standards since the stream is located within a Water Gathering Ground (WGG). Although the study of the re-use of treated effluent is continuing, this option does not appear to be economically viable.
The topography of the land and hydraulic analyses indicate that there is a significant amount of run-off during storm conditions from the contributing rainwater catchment. During a high intensity rainfall event, the stream is not able to drain adequately, and minor flooding occurs along the banks. The drainage capacity of the watercourse is limited, as the stream is generally narrow and has a shallow gradient. Hydraulic analysis of the stream indicates flooding is expected under a 1-in-2 years rainfall event, and that this situation is made worse by the existing small culverts and stream crossings which are easily blocked. DSD requirements dictate that the stream must be designed to capacity for a 1-in-50 year rainfall event.
Local residents, who were interviewed regarding existing flooding conditions, reported that flooding occurs at the rural area downstream of the village, approximately at the location of the proposed site. The locals also reported occurrences of flooding of approximately 100mm water depth in the upstream area including the existing public transport inter-change. The Terminal and Theme Village includes environmental education centres, a theatre, landscape features, a Buddhist information centre, teahouses and restaurants. As the architectural and construction requirements for the whole facility uses the entire site to the boundary, this does not permit the Ngong Ping stream to be maintained along its current route as the proposed development would be impacted significantly upon by flooding in this situation, and is considered unacceptable.
The habitat type surrounding the existing and proposed streams at Ngong Ping is a mixture of village houses (developed area), plantation woodland, shrubland habitat and active/abandoned agricultural land. Most of the existing trees are young with age less than 30 years and were planted by villagers or self seeded from abandoned cultivation. No rare or significant trees within the proposed site of the stream diversion have been recorded. A number of reptile and amphibian species have been recorded in the vicinity of the Ngong Ping Stream although few mammal species have been recorded. The stream at Ngong Ping is assessed as low/moderate ecological value, however further downstream (and upstream) the value for foraging or dispersal for animals of other habitats is high.
Various diversion schemes were assessed and compared. Engineering and architectural evaluation has been undertaken and the options were selected based on engineering feasibility, land take and environmental impact. The following three options were considered in detail:
Option 1: Maintain a Route through the Theme Village Complex;
Option 2: Divert the Stream around the Northern Boundary of the Theme Village Complex; and
Option 3: Divert the Stream across the Theme Village Complex and PTI.
Option
2 was selected: ‘Diversion of the Stream around the
Eastern Boundary of the Theme Village Complex’.
To provide an attractive and environmentally friendly channel design (i.e. with sloping or landscaped sides) and an adequate stream capacity, a relatively wide channel is required. The architectural requirements for the design of the Village are discussed below:
The Ngong Ping OZP has placed stringent restrictions on the site planning of the Ngong Ping Theme Village and Terminal that dictate the organisation and positioning of the buildings and the specific use of particular areas. It should be noted that the design of the Ngong Ping Village respects the importance of water to the tourist experience and that strategically placed water features will enhance the village while maintaining safe passage of pedestrians. Figure 1.5 illustrates the OZP areas within the site described below:
1. The OZP at the Ngong Ping Terminal site restricts the terminal to a maximum height of 12m and only allows for a small non-domestic area (retail or Food outlets). The technical and operational requirements of the terminal impose great difficulty in fitting the terminal onto the restricted area whilst maintaining the height limit. While this has been achieved, the resultant proposal does not allow for any flexibility in the repositioning or relocating of the terminal.
2. The area adjacent to the Terminal, OZP area-(A), is designated a food outlet and commercial area and is restricted to 8m in height. To optimise the spatial arrangement of the very difficult, long, linear site shape, the food outlets are located at the closest end to the terminal, where area-(A) is at its widest, as the majority of visitors will congregate outside food outlets (where it is hoped, cultural performances will also take place). The food outlet buildings have been pushed to the perimeter of the site boundary to allow the maximum available area for the visitors to the Theme Village. At area-(A), the Buddhist interpretative centre and complimentary high-tech cinema are positioned at the other end. This area is the only remaining area that can fit the buildings required for the organisation of the centre and cinema. In addition, the centre and cinema can only be placed at this location due to operational requirements as they will require the full 8m height limit.
3. The next area-(B1) leading down to Ngong Ping Road, allows for only commercial facilities and is restricted to a very low height limit of 5m. This is also a very narrow part of the site and the majority of retail will be located here.
4. The last area-(B2) provides a buffer between the commercial activities and the religious core. No commercial facilities can be positioned here and it is intended to use landscaping to create a peaceful passive recreational park.
It is important to note other specific requirements of the plan, such as the Outline Zoning Plan (OZP) which requires a minimum 6m wide continuous Tourist Corridor through the whole length of the site.
The volume of projected passengers who will experience the Theme Village emphasises the importance of designing a world quality tourist experience with a clear and smooth route through the village.
The difficult site configuration has presented a challenge for the disposition of the village components which have been, where possible, positioned on the perimeter of the long, linear site to maximise the remaining area for the anticipated volume of passengers. In particular areas of the village the positioning of the buildings restricts the route 6m wide. This highlights how essential it has been (from a safety perspective) to keep the pedestrian areas as free from restrictions and obstructions as possible.
The current positioning of all the buildings through the site has been optimised with respect to the site geometry and the restrictions of the OZP. To maintain the stream as it meanders through the site will create organisational difficulties and will diminish the overall experience of the stream in its existing position. Due to the stream crossing the site at restricted locations, it would require solid decks to be constructed over particular portions of the existing stream to allow pedestrian flow over them. In addition, where it is unavoidable to have the stream flowing under buildings, (at the cinema and Buddhist interpretative centre), these will have to be elevated on columns which will take the buildings above the (already restrictive) OZP height limit. Little of the existing stream would be visible beneath the solid decking. Again, due to the limited site, it will also be difficult to maintain a significant portion of the adjacent stream banks which further diminishes the quality of the tourist experience.
The Ngong Ping Stream is classed as a main rural drainage channel, and under the recommended DSD design standards any construction affecting the stream capacity should be designed to accommodate 1 in 50 years storm event. If the existing stream course is maintained within the site, a channel approximately 6 to 7m wide at the open channel sections will be required according to the location. This would comprise the existing stream bed which ranges from approximately 2 to 5m in width and some embankment. Where the channel passes underneath buildings box culverts would need to be provided. In addition to providing this main channel it would also be necessary to maintain connections from the existing tributaries to the main watercourse.
Under the normal DSD requirements it is necessary to provide maintenance and access to the full length of the stream. Where the stream is below ground or covered-over a drainage reserve is normally designated which would prevent the construction of buildings over the stream. This directly conflicts with any proposals to maintain the stream within the village, and safety and maintenance issues must take precedence.
It is noted that the limited space available and the requirements for crossings and culverts would significantly diminish the value of the ecology that would remain adjacent to the stream.
Whilst providing architectural challenges the difficult site configuration also provides challenges in the accommodation of the utilities necessary to serve the Theme Village and Terminal.
To maintain the existing stream course the utilities will need to pass under or across the stream to connect both sides of the site. The numerous below ground utilities required include power, water mains, local site drainage, gravity sewerage and a foul water pumping main.
There are two significant issues with regard to the water quality within the stream for the adoption of Option 1 that relate to the requirements associated with Water Gathering Grounds and value of the stream as a tourist attraction.
The first is the poor water quality that is prevalent during the dry season, as described in Section 1.7.2 above. Whilst the planned STP and Sewerage works will improve the situation, some septic tank effluent will continue to reach the watercourse until the sewerage programme is completed in 2007. A polluted stream in the middle of the site is not desirable for a world class tourist attraction.
The second issue is the prevention of pollution from the Theme Village into the watercourse as it passes through the centre of the village. To prevent pollution, cut off drains will need to be provided either side of the stream course to intercept run-off within the site to enable removal of pollution by silt traps. In addition it would be necessary to install hand rails set back from the stream to prevent pollution from tourists and staff. Whilst these would prevent pollution to a degree, it would not be possible to guarantee the prevention of pollution from human activity within the site.
An important concern for any work affecting the stream course is ensuring that the potential for mosquito breeding and hence for Dengue Fever are not made worse. With this in mind it is noted that creation of further pools or the allowance of flooding and ponding under buildings which cannot be easily reached is inadvisable from an environmental health perspective.
This option is the proposed works as described above in Section 1.6. The option retains the stream course along its existing route (as far as possible) and then diverts to the site boundary (refer to Figure 1.3). As the property boundary changes directions, bends and meanders are introduced into the proposed diversion. At the upstream end of the proposed stream, it connects to a natural section of the downstream section of the channelised portion of the existing stream which connects to the steep rocky section of the existing stream (upstream of the columbarium). The proposed stream is shorter than the replaced section of existing stream as it has fewer meanders and will have a steeper gradient which will also increase the drainage capacity.
Other surface runoff from the Theme Village Complex and Cable Car Terminal will be collected by an internal drainage system within the site, which will convey flows to peripheral trunk pipes.
The main advantage of this option over Option 3 is that where the existing stream crosses outside the boundary of the site the existing course is picked up, the stream also re-joins the existing water course at the northern portion of the site. The route also allows local water courses to be intercepted as they drain towards the Theme Village.
Following design review and consultations a combination of gabion channel, rip-rap and natural rock is proposed for both the up and downstream reaches of the stream, in preference to masonry or box culvert construction. The gabion construction will incorporate berms to encourage vegetation growth and blending with the existing environment. This type of construction has been selected as the design can both satisfy the requirements for maintenance whilst minimising the visual and environmental impacts. Where scour protection is required a rock filled gabion mattress is also proposed for the streambed to encourage vegetation growth. Ecological design and mitigation measures such as the use of boulders, meanders etc. have been used in the past on Lantau and in Hong Kong Country Parks and have been previously accepted by Government and community groups. These would be implemented in this section of the diversion.
The initial proposal for the central section was for a box culvert, since this would impact least on the local topography and land take. However this proposal received strong opposition at the consultation phase because of the environmental loss. An alternative design for the open culvert is currently under review. The revised proposal for the central section comprises open channel constructed from either gabion construction or an alternative trapezoidal channel as illustrated in the indicative cross sections given in Figure 1.4. This alternative will need to be agreed by Drainage Services Department, and the additional land-take will also need to be confirmed by CPMB before the design can be confirmed.
The proposed drainage ditch (to the west of the site) is a diversion of an existing ditch that merges into the main stream, and primarily intercepts the natural runoff to the south west of the proposed site and prevents runoff from entering the Theme Village. Rip-rap is proposed to blend in with the rocky section downstream, and to minimise the amount of construction works as local rocks and stones can be utilised. The use of the existing gully lined with boulders will provide ecological habitat, create a scenic environment and prevent erosion.
The design proposals described above have been made with reference to the EPD booklet “Examples of Environmentally Friendly Drainage Channel Designs Arising From Environmental Impact Assessments” and notably the following design measures have been adopted:
· use of varied bank materials other than concrete.
· replanting along the new channel banks.
· creation of meanders within the proposed channel.
It is proposed that the form of the proposed design be further reviewed by the Green Groups and EPD before it is finalised and approved by DSD.
This option comprises constructing a new channel across the narrowest section of the Theme Village Complex (refer to Figure 1.6). This option does not intercept all the existing stream tributaries and ditches, and an additional drainage system consisting of U-channels or a new ditch would still be required along the route proposed in Option 2 to intercept local tributaries. In addition the possible stream routes around the west of the Theme Village had potential to disturb graves in the vicinity. This option would provide a barrier for the provision of services to the Terminal and would require a land take, which is currently unavailable and has cultural heritage implications (i.e. the close proximity of graves).
To date no option for maintaining a route through the village has be able to address all the requirements and concerns of the design as discussed in Section 1.8.1. Furthermore a primary objective for maintaining the stream within the Theme Village is the maintenance of the natural aquatic ecology. It is clear that the negative impacts of constructing box culverts beneath buildings, providing only a limited stream width and bank, and provision of numerous crossings would effectively diminish the existing stream course to the extent that it has a very low ecological value.
For the reasons given in the foregoing sections it was concluded that Option 2 is the preferred option.
The diverted stream will fall within the Lantau North Country Park and will discharge into an area that is less than 300m from the nearest boundary of an existing Conservation Area. The proposed stream diversion is a designated project (DP) under the Environmental Impact Assessment Ordinance (EIAO) (Cap. 499) under Schedule 2 Part I Item I.1 or Q.1 of the EIAO. The stream is to be diverted out of the Ngong Ping Cable Car terminal site, which is a Designated Project. The EIA for the Tung Chung Cable Car is currently included on the Register (Application no. EIA-090/2003).
The stream diversion is being planned and designed by MTR and their appointed Consultants. This work commenced with the project conception at the start of 2003 and is due for completion in September 2003.
The works will be implemented by MTR’s appointed Contractor, the anticipated date for award of the Construction Contract is the start of September. It is proposed that the works will be undertaken in the dry season, between October 2003 and January 2004.
The works will be sequenced (in three sections) so as to minimise the number of construction vehicles and traffic affecting the surrounding areas.
1. The works will commence on the west side of the site in order to
divert the existing ditch away from the Ngong Ping Terminal area. The work will be undertaken utilising one
excavator. The second section of works to be commenced will be the north-west
downstream reach of the proposed main stream alignment between the downstream
connection point and the bisection with the existing stream course (approximate
chainages 235 to 304m).
The section will be undertaken utilising one excavator. The existing stream will then be diverted
into the new alignment.
2. After the diversion of the downstream reaches the northern section of the main stream will commence. Within this section two excavators will be deployed, one starting at the west end of the channel and moving east, with the other starting at the mid-point and also moving east. The distance between the two will be in the region of 50 metres (as minimum distance). Within this section a higher hoarding will be erected to offer greater protection to the existing residences along this alignment. Where these act as noise barriers they will consist of a 3 metre high, 20mm thick wood/ply hoarding.
3. Once the second section has been completed the stream to the north-east will be realigned. The final section of the proposed stream in the eastern section will be constructed utilising one excavator allowing the full diversion of the stream to be completed.
As
far as possible the excavated material will be reintroduced into the works.
This will not only reduce, or eliminate, materials being sent to landfill
sites, but it will also limit the amount of construction traffic accessing the
existing road infrastructure. Sections 34.4 and 5.3 describe the potential waste
impacts in detail.
From the outset of the Tung Chung Cable Car Project, MTR has consulted with the stakeholders, and it is their intention to continue with this practice during Construction.
Due to the close proximity of residential property, it will be just as important that the contractor operates an effective public relations strategy during the construction phase. This will involve the use of leaflets or notices either posted to the individual residences or posted on the site advising the programme of the works, and the scope of those works, with particular attention given to undertaking noisy works. This will be especially important during the excavation of rock. Details given will also include a contact number should any of the residents wish to raise a complaint. This strategy will also be extended further to cover regular liaison meetings with the site staff.
The Stream Diversion Works will interface with following projects:
1. Tung Chung Cable Car Project (TCCCP) - The Stream Diversion Works form an addition to this project and to minimise the impacts it is proposed that the same contractor undertakes both sections of the work. Under the tentative programme of works the only activity under TCCCP to be carried during the Stream Diversion Works will be site clearance and formation. This is likely to involve the use of excavators and site lorries. A minimum working distance of 50m shall be maintained at all times for safety reasons and to minimise accumulated impacts. It is noted that the piling works for the Cable Car Terminal are programmed to be undertaken after the Stream Diversion Works.
2. The proposed Transport Department PTI at Ngong Ping – It is understood that TD will entrust the construction of the PTI to MTR, the anticipated agreement date is August 2003.
3. Outlying Islands Sewerage Stage 1 Phase 1, Ngong Ping Sewage Treatment Works and Sewerage Design and Construction. DSD Agreement CE 29/2001. Design Liaison is ongoing between MTR’s design team and DSD throughout the design process for the Cable Car and Stream Diversion Projects.
4. The proposed Territory Development Department Piazza at Ngong Ping – At present the programme for the Pizza has not been determined although it is anticipated that the Piazza will be completed within the Cable Car Project timeframe. The Piazza is upstream of the project and will not directly impact upon the stream diversion works. The drainage impact from Piazza has been accounted for in the hydraulic design.
The local traffic such from Ngong Ping Road and other local roads is considered to be the dominant source affecting the ambient air quality in Ngong Ping and its environs. No industrial uses are located within the area.
Representative Air Sensitive
Receivers (SRs) within 500m of the Project limit have been identified according
to the criteria set out in the TMEIA and through site inspections and a review
of land use plans. At this site the Sensitive Receivers are the same for noise
and air and their horizontal distances to the nearest emission source have been
identified and are summarized in the Table
43.1 below. Locations of the SRs are shown in Figure 43.1.
Table 333333.111111: Locations
of Air and Noise SRs
|
SRs |
Receiver
Description |
Usage |
Distance to
the nearest Emission Source |
|
SR1 |
Village House |
Residential |
28 |
|
SR2 |
Village House |
Residential |
12 |
|
SR3 |
Village House |
Residential |
6 |
Ngong Ping Road and other local roads and occasionally smoke from residences are the dominant air pollution sources at the Study Site.
Representative Noise
Sensitive Receivers (SRs) within 300m of the project limit have been identified
according to the criteria set out in the TM-EIA and NCO, through site
inspections and a review of land use plans. At this site the Sensitive
Receivers are the same for noise and air and their horizontal distances to the
nearest emission source have been identified and are summarized in Table 43.1 above. Locations of the SRs are shown in Figure 43.1.
The Ngong Ping Stream flows
through the site boundary at the Cable Car Terminal and Theme Village Complex.
While there are no records of the water quality in this stream, observations
between 2002 and 2003 (Mott Connell) indicate that the water course is stressed
through the effects of pollution primarily from domestic sources. Existing
pollution sources generally related to the domestic effluents generated by the
Ngong Ping community. Plates taken
in June 2003 (refer to Appendix
A) show the low flow and visible poor water quality of the
stream. Figure A.1 shows the
locations of where the photographs were taken.
Plans to construct the Ngong Ping Sewage Treatment Plant and sewerage scheme will remove this source of pollution away from this stream in 2007 when all village houses are connected to the STP and water quality is expected to improve greatly. Although some water quality improvement will occur after 2005, it is anticipated to remain poor in the diverted stream until full connection of the Ngong Ping Village sewerage by 2007.
The Ngong Ping Stream is a sensitive receiver as well as the WGG in which the stream is located.
The
stream at Ngong Ping has been comprehensively investigated component of the Project through
a series of field surveys and literature reviews for this study as well as the
Ecological Baseline Study (BMT, 2002) which provided the basis for the approved
Tung Chung Cable Car EIA (Mott Connell, 2003) (approved by Government) and the
approved Ngong Ping Sewage Treatment Works EIA (Ove Arup and Partners Hong
Kong, 2002). These approved reports and
further ecological surveys provide the ecological basis for the stream
diversion report. Some ecological
literature used are:
1. Agreement No. HKI 1/2002 Tung Chung Cable Car Project: Ecological Baseline Survey. (BMT, 2002).
A detailed ecological baseline survey, based on the final proposed alignment (and associated infrastructure). This report presents the findings of a literature review and focused field surveys that were undertaken within the Study Area from May 2002 to January 2003. BMT Asia Pacific Limited (BMT) were commissioned by the Territory Development Department (TDD) to undertake an Ecological Baseline Survey on the 9th May 2002 for the proposed Project. The report was the basis the Tung Chung Cable Car EIA.
2. Agreement No. CE 29/2001 Outlying Islands Sewerage Stage 1 Phase 1 Ngong Ping Sewage Treatment Works and Sewerage Investigation, Design and Construction: Final Environmental Impact Assessment Report (Ove Arup and Partners, 2002).
An EIA conducted adjacent to the stream diversion location which has. The EIA’s Study Area encompassed the location of the proposed stream location. The study evaluated environmental impacts including cumulative impacts associated with the Tung Chung Cable Car Project.
3. Agreement No. CE 1/97 Remaining Development in Tung Chung and Tai Ho Comprehensive Feasibility Study Working Paper No. WP10, Review of Cable Car Proposal (Mott Connell Ltd, 1998).
A preliminary ecological assessment which highlighted the ecological concerns of the Project including implications for the Country Park and ecological impacts during construction and operation for proposed alignment options. This Study evaluated impacts associated with each of six alignment options and Project alternatives.
4. Consultancy Agreement NEX/034 Tung Chung Cable Car Feasibility Study: Final EIA Report (Mott Connell Ltd, 1999).
A detailed ecological assessment, which discusses the ecological implication of constructing and operating a Cable Car route between Tung Chung and Ngong Ping. Based on field surveys conducted from July to October 1999 and a literature review, existing baseline ecological conditions of the site are described and the key ecological resources of the area highlighted. Potential ecological impacts arising from the proposed cable car are identified and their significance evaluated.
5. Other relevant literature such as Porcupine! (a newsletter of the Department of Ecology and Biodiversity, the University of Hong Kong); Memoirs of the Hong Kong Natural History Society.
The
ecological field survey conducted in the EIA was undertaken according to Table 34.23.
In addition to the baseline literature (primarily from the EIA), Mott Connell
conducted additional ecological surveys to verify baseline data and literature.
Table 333333.222222: Summary
of Ecological Surveys undertaken by BMT (2002) and Mott Connell (2002 and 2003) of the Study Area
|
Type of Survey |
Source |
Date Undertaken |
Brief Methodology |
|
Vegetation |
BMT |
September 2002 October 2002 |
A site walkover and vegetation plot at the Ngong Ping terminal was undertaken. Parameters recorded included species richness and abundance. Plants encountered were identified and their conservation status reported according to Zing et al. (2000). |
|
|
Mott Connell |
19 December 2002 06 June 2003 12 July 2003 13 July 2003 |
Site inspection which included site walkover through the major habitat types adjacent to the stream alignment and proposed stream diversion. |
|
Tree |
Mott Connell |
January 2003 February 2003 March 2003 April 2003 |
All tree species systematically recorded (location), marked (numbered) and identified for a tree felling application. |
|
Mammal |
BMT |
19 May 2002 6 June 2002 26 June 2002 3 August 2002 10 September 2002 October 2002 17 December 2002 |
Direct and indirect observation (scats, tracks, tree markings etc.) of mammals in the Study Area. Observation were made through a combination of day time and night time survey. |
|
|
Mott Connell |
06 June 2003 12 July 2003 13 July 2003 |
Direct and indirect observations (scats, tracks, tree markings etc.) of mammals within the vicinity of the stream course and proposed stream diversion. |
|
Herpetofauna |
BMT |
19 May 2002 6 June 2002 26 June 2002 31 July 2002 3 August 2002 21 September 2002 25 September 2002 5 October 2002 17 December 2002 |
Herpetofauna were determined by direct and indirect observations. Suitable habitats in close proximity of the Study Area were examined. The presence of species were investigated during day time and night-time. A net was used to catch amphibians where visual observations were not sufficient for identification. |
|
|
Mott Connell |
06 June 2003 12 July 2003 13 July 2003 |
Direct observations (calls, sightings) of herpetofauna within the vicinity of the stream course and proposed stream diversion. |
|
Insect |
BMT |
6 June 2002 26 June 2002 3 August 2002 24 August 2002 10 September 2002 25 September 2002 5 October 2002 27 October 2002 28 November 2002 14 December 2002 17 December 2002 |
Species of butterfly and dragon fly in the Study area were determined by direct observations. All butterflies and dragonflies were identified to species level, and their status noted according to Wilson (1997) for dragon flies and Chung (2001) for butterflies. Vegetation for butterflies of conservation significance was noted. |
|
Avifauna |
BMT |
28 May 2002 15 August 2002 14 October 2002 27 November 2002 14 December 2002 11 January 2002 |
Line transects of major habitat types were selected and surveyed. Bird surveys commenced close to dawn to coincide with peak activity of most bird species. |
|
|
Mott Connell |
06 June 2003 12 July 2003 13 July 2003 |
1 hours bird survey commenced close to dawn to coincide with peak activity of most bird species was undertaken. Incidental observations were also recorded. |
|
Stream |
BMT |
6 June 2002 24 August 2002 25 September 2002 28 November 2002 14 December 2002 |
Stream survey primarily involved investigation of freshwater fish and macroinvertbrates. Observations of infauna were generally made in-situ, underneath stones on stream banks and pools. |
Note: BMT
(2002) surveys were for the EIA Study Area which contains the Stream Diversion
Site.
Ngong Ping SSSI was designated in May 1999 as its seasonal wooded streams provided habitat for the endemic and rare Romer’s Tree Frog Philautus romeri. This SSSI is in an area located outside the Country Park. It was a former tea plantation area and is of special scientific interest due to the presence and the confirmed breeding of the locally rare Romer's Tree Frog (Philautus romeri). The Ngong Ping valley was confirmed to support the largest population of the endemic Romer's Tree Frog.
The
habitat type surrounding the stream at Ngong Ping is mixture of village houses
(developed area), plantation woodland, shrub habitat, active/abandoned
agricultural land. The major vegetation types at
the Ngong Ping are shown in Appendix A. A
map showing the approximate locations of these vegetation types is shown in Figure 3.2.
An
approximate total of 250 trees are located within the Stream Diversion works
site. Approximately Table
3.3 shows the number of trees affected by the stream
diversion.
Table 333333.333333: Number
of Trees Transplanted, Retained and Felled for the Stream Diversion
|
Action |
Number
of Trees (approx.) |
Reason
for Felling |
|
|
Existing
Stream |
Diverted
Stream |
||
|
Transplantation |
2 |
1 |
- |
|
Retained |
6 |
80 |
- |
|
Fell |
42 |
120 |
Within development footprint |
|
Approximate
Total |
50 |
201 |
|
An
approximate total of 250 trees are located within the Stream Diversion works
site of which approximately 160 will require felling. The number of trees included a 5m construction buffer surrounding
the stream and proposed diversion.. The
majority of tree species which require felling (in order of abundance) are: Acacia confusa, Machilus chekiangensis,
Mallotus paniculatus, Symplocos lancifolia, Casuarina equisetifolia,
Ligustrum sinense, Schefflera octophylla and Dimocarpus longan.
The majority of the plantation species comprise common exotic species, in particular Acacia confusa, which is planted throughout Hong Kong. Other common local species recorded include: Gordonia axillaris, Machilus chekiangensis, Mallotus paniculatus, Schefflera octophylla, Symplocos lancifolia and Syzygium jambos.
Most of the existing trees are young with age less than 30 years and were planted by villagers or self seeded from abandoned cultivation. No rare or significant trees within the proposed site of the stream diversion have been recorded. Most trees at Ngong Ping area are generally small or medium in size. Both sites comprise a mix of ornamental exotic and native species of trees, shrubs and herbs. Table 3.4 evaluates plantation within the Study Area using the Criteria listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 333333.444444: Evaluation
of Plantation at Ngong Ping
|
Criteria |
Remarks |
|
Naturalness |
These plantations were established by man and are artificial. However, some of the plantations at Ngong Ping are becoming more natural over time. There are generally dominated by planted exotic species. |
|
Size |
The plantation areas within the Study Area are relatively restricted |
|
Diversity |
Species diversity is low. |
|
Rarity |
Widespread throughout the SAR. |
|
Re-creatability |
Plantation habitats could easily be created but would need about 20 years to mature to the current stage. |
|
Fragmentation |
The plantation habitats are relatively small and fragmented by paths and houses. |
|
Ecological linkage |
The plantation link areas of natural habitats are probably of medium value for foraging or dispersal for animals of other habitats. |
|
Potential value |
Low but increasing as more native species become established. The monoculture areas dominated by Aciacia confusa are considered to be of low potential value. |
|
Nursery/ breeding ground |
The plantation habitats are not expected to provide anything more than breeding sites for birds. |
|
Age |
Young, relatively recent and regularly re-created as the result of hill fires. The plantations are about 25-30 years old. |
|
Abundance/ richness of wildlife |
Low, these
plantation habitats do not contain high species richness for wildlife. However, a |
|
Summary |
The plantations within the Study Area are generally evaluated as of moderate ecological value but they may support a number of breeding birds on the Ngong Ping plateau and provide a surrounding habitat for the Romer’s Tree Frog. |
Note: Evaluated using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
The number of species in shrubland habitat were recorded, these include: Blechnum orientale, Aster baccharoides, Cibotium barometz, Breynia fruticosa, Altingia chinensis, Archidendron clypearia, Archidendron lucidum, Acacia auricumormis, Ardisia crenata, Ardisia quinquegona, Baeckea frutescens, Adina pilulifera and Camellia euryoides. Shrub habitat appears to have resulted from fire and to an extent a change in land use (abandonment of cultivated land). The shrub habitat varies in age throughout the Study Area, but generally appears to be about 5-10 years old. Table 3.5 evaluates shrubland within the Study Area using the Criteria listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 333333.555555: Evaluation
of Shrubland Habitat at
Ngong Pingwithin the Study Area
|
Criteria |
Remarks |
|
Naturalness |
The shrubland habitats are natural but modified and maintained as shrub generally by thin/infertile soils, erosion, and/or irregular hill fires. They are dominated by native species. |
|
Size |
The shrubland areas within the Study Area are of moderate size. |
|
Diversity |
Species diversity is typical for shrubland in the area and considered low to medium. |
|
Rarity |
Shrubland is widespread on Lantau and in the SAR. |
|
Re-creatability |
Shrublands are at the early stage of the vegetation succession and are relatively easily re-created. |
|
Fragmentation |
This shrubland is relatively continuous. |
|
Ecological linkage |
This shrubland is probably of low to medium value for foraging or dispersal for animals of other habitats. |
|
Potential value |
In the absence of hill fires and with improved soil conditions and less soil erosion the hillside Low shrublands could develop over time into tall shrubland and then woodlands which would be of greater ecological value. |
|
Nursery/ breeding ground |
Low. |
|
Age |
Relatively young. |
|
Abundance/ richness of wildlife |
Low. |
|
Summary |
The low shrub habitats within the study are generally evaluated as of low to moderate ecological value. |
Note: Evaluated using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
Cultivation (orchid) and abandoned cultivation include: Citrus reticulata, Dimocarpus longnan and Psiudium guajava. No rare or protected trees were noted to date. Table 3.6 evaluates cultivation/ abandoned cultivation within the Study Area using the Criteria listed in Table 2 of Annex 8 of the Technical Memorandum.
Table 333333.666666 Evaluation
of Cultivation/ Abandoned Cultivation at Ngong Ping
|
Criteria |
Remarks |
|
Naturalness |
The cultivation land is man-made and not considered natural. Abandoned cultivation is progressing towards a natural environment. |
|
Size |
The cultivated areas are restricted to small areas adjacent to the stream. |
|
Diversity |
Species diversity is low to moderate for cultivation due to the nature of the species planting. |
|
Rarity |
Cultivation is not restricted on Lantau or the HKSAR. |
|
Re-creatability |
Easily re-created. |
|
Fragmentation |
This cultivation is fragmented. |
|
Ecological linkage |
These cultivated
habitats are of value to some bird species providing nesting habitat. However in general (i.e. for mammals) it
likely to be of limited value for foraging or dispersal for animals of other
habitats. |
|
Potential value |
These cultivated
lands could scrub up and could develop over time |
|
Nursery/ breeding ground |
Low. |
|
Age |
Varying ages, some cultivation is young (i.e. a few years) to older abandoned cultivation may be over 15 years old. |
|
Abundance/ richness of wildlife |
Moderate
abundance, in particular the stream banks of cultivation and abandoned
cultivation provide habitat for amphibians. Bird species were observed in
abandoned cultivation. |
|
Summary |
The cultivation
within the Study Area is generally evaluated as of low ecological value. |
Note: Evaluated using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
From
the dark appearance of the water and the fine sediment character and odour from
disturbed sediment, it is likely that the stream receives waste discharge from
the nearby Village areas. This observation is supported by discharge from
broken sewerage near the Stream and the infauna that characterises this stream
(BMT, 2002). Table 4.3 evaluates the
ecological value of Ngong Ping Stream. The EIA conducted by Mott Connell (2003) (BMT, 2002) reported
that both the freshwater snail Physa
acuta and larvae of Chironomus/
Polypedilum spp. were dominant in the snail being an indicator of organic
pollution and the Dipteria larvae indicators of low oxygen environments.
Table 3.7
evaluates stream
habitat within the
Study Area using the Criteria listed in Table 2 of Annex 8 of the Technical
Memorandum.
Table 333333.777777 Ecology
Evaluation of Ngong Ping Stream Habitat
|
Criteria |
Remarks |
|
Naturalness |
The watercourse contains modified (upstream section)/ semi-natural (downstream section) and is dominated by a mixture of introduced and native species. |
|
Size |
The watercourse within the Study Site is linear in nature and connects to the Sham Wat Stream. |
|
Diversity |
Species diversity is moderate. |
|
Rarity |
Modified watercourses are common although natural watercourses with clear water are very restricted. |
|
Re-creatability |
Modified watercourses are easily created although natural watercourses are not easily re-created. |
|
Fragmentation |
These watercourses are linear and continuous; they flow from mountain to sea. |
|
Ecological linkage |
The stream at Ngong Ping moderate ecological value however further downstream (and upstream) the value for foraging or dispersal for animals of other habitats is high. |
|
Potential value |
High. |
|
Nursery/ breeding ground |
The natural watercourses provide important breeding grounds for amphibians, fish and invertebrates particularly at and further downstream at the Sham Wat Stream where species of conservation interest have been recorded. |
|
Age |
Not applicable. |
|
Abundance/ richness of wildlife |
Moderate for a variety of different taxa including plants, invertebrates, amphibians and reptiles. |
|
Summary |
The watercourses within the Study Site are generally evaluated as of moderate ecological value due to human disturbance. |
Note: Evaluated using the Criteria Listed in Table 2 of Annex 8 of the Technical Memorandum
Although the Ngong Ping Stream has relatively poor water quality (i.e. visible hydrocarbon sheen on the surface and sedimentation) (Mott Connell, 2003), the stream habitat has a high potential ecological value (particularly upstream and downstream of the Project Site), although the current condition is generally moderate (and low in some areas). A number of species of conservation interest have been recorded near the Ngong Ping Stream. Tadpoles of Romer’s Tree Frog Philautus romeri were found in seasonal streams at the stream of Ngong Ping in the SSSI, however these locations (or stream sections) are not in close vicinity of the Ngong Ping Terminal site (BMT, 2002). Appendix E lists the amphibian records and survey results at Ngong Ping Plateau.
During surveys by Ove Arup and Partners (2002) a number of tadpoles of Romer’s Tree Frog Philautus romeri were found in seasonal streams at the stream of Ngong Ping in the SSSI, however these locations (or stream sections) are not in close vicinity (i.e. within 500m) of the Ngong Ping Terminal site. In terms of habitat type, P. romeri generally prefers low shrub and grass in well-vegetated flat areas where it predates on spiders and small insects such as termites and crickets (Karsen et al., 1998). The preferred habitat is commonly near a stream course or another source of water that is convenient for breeding (as noted by Lynch, 2001). Given its small size and predation pressure faced by larger amphibians, this species is of limited mobility and so is very sensitive to habitat fragmentation. Romer’s Tree Frogs are mostly found within the plantation woodland and tall shrub habitat in the Ngong Ping SSSI (Ove Arup and Partners, 2002). This species is protected under the Wild Animals Protection Ordinance, Cap. 170. The same survey also recorded the restricted Megophrys branchykolos, possibly another endemic species.
Amphibian
species of ecological interest, the Leaf Litter Toad Leptolalax pelodytoides, recorded close to the Study Area. The Leaf Litter Toad is a fairly restricted
and uncommon species in Hong Kong and has been reported in the hill streams
near Ngong Ping (Lau and Dudgeon 1999).
The other seven species of frog and toad (Asian common Toad Bufo melanostictus, Gunther's Frog Rana guentheri, Green Cascade Frog Rana livida, Three-striped Grass Frog Rana macrodactyla, Brown Tree Frog Polypedates megacephalus, Asiatic Pained
Frog Kaloula pulchra and Ornate Pigmy
Frog Microhyla ornata are common to
abundant and are widespread locally at Ngong Ping (Karsen et al. 1998).
Mott Connell surveys (refer to Appendix E) confirmed the presence of some of the species at the Ngong Ping Stream. A large number (approximately 75+ individuals) of Brown Tree Frogs were observed in cultivation/ abandoned cultivation and heard from riparian vegetation along the existing stream. Large numbers of Brown Tree Frogs were also located in the drains throughout Ngong Ping Village.
Table 4.5Appendix E summarises details from various sources of reptile records made
around Ngong Ping. Amongst these, the terrapin Chinemys reevesii, found in seasonal streams at Ngong Ping, is
listed as “endangered” in the IUCN Red List. Of the snakes, Achalinus rufescens is
rare; Amphiesma stolatum and Oligodon cinereus are uncommon/
restricted; and Elaphe radiata is
listed as “endangered” in the China Red Data Book (Zhao, 1998 in Ove Arup and Partners, 2002).
A
number of restricted and/or uncommon reptiles have also been recorded in the
Study Area Rufous Burrowing Snake Achalinus
rufescens, found in the plantation, tall shrubland and forest at Ngong
Ping; Buff-striped Keelback Amphiesma
stolatum, found in a stream at Ngong Ping (Kolby and Lazell, 2001).
Records
from the Hong Kong Lepidopterists’ Society (HKLS) include ‘several’ Troides aeacus on the path from Ngong
Ping to Tung Chung (outside the Study Site) in September 1999 (Wong, 1999) and
in September 2000 (Wong, 2000). During the 1999 visit it was noted that Zanthoxylum nitidium flowering along the
path attracted the species. Butterfly
records are provided in Appendix E. In addition the Butterfly Food Synergies are provided in Appendix F. Lantana camara is recorded throughout Ngong
Ping Terminal and adjacent to the existing stream (a foodplant for Troides Helena). However, no historical or current record of Troides helena at this location has have been recorded.
Field survey undertaken for the Cable Car EIA (Mott Connell, 2003) indicated that the odonate community along the Cable Car alignment was rather less diverse than that of the butterflies. Of particular note was 2-5 individuals of Orthetrum pruinosum (abundant species) in the middle of the Ngong Ping Stream (outside the stream diversion construction area).
The
birds recorded in the habitats near Ngong Ping Terminal, are generally common
and widespread species that are typical in disturbed areas with a human
presence and a partly built environment. Appendix
E lists the avifauna records and survey results . Abandoned cultivation and plantation have been
identified as suitable habitat for some common bird species.
Notable records from Ngong Ping cited in Ove Arup and Partners (2002) include the Brown Thrush Turdus chrysolaus, Mountain Bush Warbler Cettia fortipes, Mugimaki Flycatcher Ficedula mugimaki, and Tristam’s Bunting Emberiza tristrami. All these species are rare or uncommon migrants that can be found in tall shrub, woodland and/ or plantation (Viney et al, 1994). The bird survey undertaken by Ove Arup and Partners (2002) also recorded two rare species: the Chestnut Bulbul Hemixos castanonotus in plantation and woodland and White’s Thrush Zoothera dauma in woodland. The precise location of these observations is unknown, although as wooded habitat is present throughout the general surroundings there is potential for activity by these species within the Study Area.
There
are few records of terrestrial mammals from the Study Area. Ryukyus Mouse Mus caroli, a locally restricted
species, has been recorded in the grassland at Ngong Ping. Appendix E lists the amphibian mammal records and survey results at Ngong
Ping Plateau. About 30 domestic dogs
were observed during a survey near the existing stream. Impacts from dogs on other species (mammals)
is a possible explanation for the low number of mammal records. Cattle were also obverted near the existing
stream.
The Ngong Ping Stream is potentially a sensitive receiver and has been considered in the assessment as well as the Water Gathering Grounds.
Ngong Ping area consists of distinct landscape character units (LCU) and can be readily differentiated from neighbouring areas. The landscape units identified at Ngong Ping are:
· Monastery and Village Settlement;
· Buddha Statue;
· Ngong Ping Road; and
· Transport Terminus and Burial Areas.
The proposed stream diversion site is located within the burial area LCU. The centre of the site is relatively level ground surrounded by a series of small rocky knolls with mainly hillside scrub and grass vegetation cover. A small stream meanders across the site. There is a belt of amenity tree planting by the side of the access road. The existing and proposed stream is located within this LCU and although it does not impact directly on the graves it will result in the permanent loss of mainly scrub and grass vegetation and require re-channelling of the stream course. The impacts are discussed more fully below.
In typical visual impact assessments, the VSR group represented by tourists and pedestrians would generally be considered of low sensitivity due to the transitory nature of the visual impacts. However, for this study, worshippers and tourists visiting the Buddha and Po Lin Monastery are considered to be of high sensitivity. Visitors travelling to Ngong Ping come primarily to worship and enjoy the peaceful ambience of the Buddha and Monastery in a dramatic mountain setting.
The monastery buildings and adjacent village settlements within Ngong Ping are low-rise and set amongst relatively dense and mature copses of plantations. As a result the proposed stream will be screened from street level including the Di Tan ceremonial platform and temple buildings within Po Lin Monastery.
The
location of the existing stream and key areas of landscape plantation are shown on Figure 35.21 with the anticipated development
‘footprint’ and stream realignment to indicate the scale and extent of the
impact. The typical landscape character of the site, i.e., a stream meandering
gently through areas of shrubland or abandoned farmland, re-colonised in most
cases by grass and shrub vegetation.
Copses of semi-mature and mature trees are located along portions of the
banks usually in association with adjoining roadside amenity planting or small
orchards. The majority of the amenity
planting comprises common exotic species such as Acacia confusa, used throughout Hong Kong. Other common local species noted include; Gordonia axillaris, Machilus chekiangensis,
Mallotus paniculatus, Schefflera octophylla, Symplocos lancifolia and Syzygium jambos. The orchard fruit trees are mainly; Citrus reticulata, Dimocarpus longnan and Psiudium guajava. No rare or protected trees were noted to
date.
The area proposed to accommodate the realigned stream is broadly similar in landscape character, that is; scattered copses of plantation with a mix of low shrub and grass under storey on the periphery of the Ngong Ping Village area.
The main VSR group affected by the new stream alignment will be Village residents and to some extent visitors exploring the are causing the local lanes and paths. This group of VSRs will be closest to the stream diversion located along the north and west perimeter of the Cable Car Terminal and Theme Village Complex. The number of VSRs in this group is difficult to estimate but will include a relatively small number of residents and visitors to the adjacent Village houses, visitors en route to the columbarium and adventurous tourists.
The second main group of VSRs affected will be the Cable Car passengers who will look down on the stream course as the gondolas pass over. The number of VSRs will be very large.
The stream diversion works will be located in an area of former fields; existing impacts in the area include paths, residential and religious buildings. At the end of the cable car the Ngong Ping Monastery is located on alluvial deposits.
No archaeological sites have been recorded in the area that will be directly impacted by the proposed project.
Three shrines have been recorded within the works area, two will be directly impacted and one will be indirectly affected due to its’ close proximity.
There is no record of habitation at Ngong Ping prior to the construction of the first buildings associated with the Po Lin Monastery. However, there are references to cultivation of tea on the southern slopes of Lantau Peak in the late 1880s and 1890s. Hayes records an interview with a Tung Chung woman born in 1879 who picked tea at plantations in that area as a child. The plantations were apparently run by Chinese from outside the island (Hase, Hayes and Lu 1986).
The
Po Lin or ‘precious lotus’ monastery was founded in 1905 by three monks. Prior
to this the area was uninhabited. The monastery was officially inaugurated in
1928 (Rodwell). Original buildings associated with the monastery were simple hermitages
built between 1909 and the 1930s; they were later replaced by new buildings
including the Po Lin Monastery which opened in 1970. Today the monastery
complex contains numerous religious buildings, residential units and associated
shops and restaurants.
The field survey confirmed that the only heritage resources within 200 metres of the project boundary were indeed those associated with the Po Lin Monastery and structures in Ngong Ping. At this distance, there will be no direct impacts to any of the structures and any adverse indirect impacts will be minimal, hence, the resources were recorded collectively and will be assessed as such. The Po Lin Monastery consists of a large number of religious buildings. There are also shops and restaurants spread around the area. The settlement of Ngong Ping is not a traditional village and grew up as a result of the establishment of the nearby monastery. The structures include a number of religious and residential buildings of various dates and styles.
The three shrines are potential The Ngong Ping Stream is a sensitive
receivers as well as the WGG in which for the stream worksis located. The location of the graves and shrines in
the vicinity of the works are shown in Figure
43.6.
The
Tung Chung Cable Car EIA reported the findings of a hazard assessment for the
Tung Chung Cable Car System. The EIA Study Brief (No. ESB-068/2001) required
the assessment of risk to passengers and workers of the Cable Car due to the
fuel storage at Hong Kong International Airport tank farm. No source of hazard to life .has
been identified as part of the stream
course works.
The
impacts associated with the stream diversion are assessed according to the
criteria listed in Annexes of the Technical Memorandum on Environmental Impact
Assessment (TMEIA). The major potential
impacts during construction and operation associated with the stream diversion
are show below in Table
34.1.
Table 444444.111111: Major
Potential Impacts during Construction and Operation Associated with the Stream
Diversion
|
Potential Impacts |
Phase |
||
|
Construction |
Operation |
||
|
Air quality |
Dust pollution |
ü |
û |
|
|
Odour pollution |
û |
û |
|
|
Exhaust emissions |
û |
û |
|
|
|
|
|
|
Noise |
Machinery |
ü |
û |
|
|
|
|
|
|
Waste generation |
Disposal of spoil |
ü |
û |
|
|
|
|
|
|
Water quality |
Effluents |
ü |
û |
|
|
Erosion and sedimentation |
ü |
ü |
|
|
|
|
|
|
Ecology |
Impacts on fauna |
ü |
ü |
|
|
Impacts to flora |
ü |
û |
|
|
|
|
|
|
Landscape and visual amenity |
Unsightly visual amenity |
ü |
û |
|
|
Landscape amenity |
ü |
û |
|
|
|
|
|
|
Archaeology/ cultural heritage |
Disruption to Buddhist activities |
ü |
û |
|
|
Excavation of graves |
û |
û |
|
|
Re-location of shrines |
ü |
û |
|
|
|
|
|
|
Risk |
Accidents leading to pollution |
ü |
û |
|
Hazard to life |
|
û |
û |
Notes: ü= Possible; û = Not anticipated
It should be noted that the potential impacts during the operation phases are sedimentation and fauna. For all other environmental aspects the focus of attention has concentrated on the construction phase.
This section outlines the potential air quality impacts arising from the construction of the proposed stream diversion at Ngong Ping. An air quality assessment has been undertaken to define the nature and scale of potential environmental impacts, specifically in terms of the effects in the vicinity of sensitive receivers. Construction phase impacts have been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels.
Construction activities that may generate air quality impacts include:
· dust generated from site clearance of the proposed stream alignment;
· dust generated from rock-breaking in the proposed stream bed;
· dust generated from excavation of the proposed stream bed;
· dust generated by vehicle movement; and
· exhaust emissions of SO2 and NO2 from the diesel-powered mechanical equipment.
Ready mix or in-situ concrete/grouting will be used. This means that there will be no need for a concrete batching plant to be established on-site.
The extent of impacts depends on the distances between the work sites and the identified Sensitive Receivers (SRs), the construction methods employed and the number of plant used and vehicle movements.
The extent of dust impacts arising from the construction of Cable Car Project have been predicted using the USEPA approved model Fugitive Dust Model (FDM) in conjunction with the construction programme. The Compilation of Air Pollutant Emission Factors, 5th Edition, US Environmental Protection Agency, 1996, (AP-42) was used to determine the various fugitive dust sources.
Emission factors, for various fugitive dust sources have been determined based on the USEPA Compilation of Air Pollution Emission Factors, 5th Edition (AP-42). Detailed calculations of the emission factors are given in Appendix B.
The
dust emission from construction is associated with site clearance,
rock-breaking, excavation and vehicle movement on unpaved road. The emission factor for general construction
is illustrated in Table 34.2.
Table 444444.222222: Emission
Factors for Various Construction Activities
|
Activities |
Emission
Factors |
Remarks |
|
Material Handling |
4.39 x 10-3 g s-1 |
Based on USEPA AP-42 Vol. 1 5th Edition, Section 13.2.4.3 |
|
Rock Breaking |
1.37 x 10-5 g s-1 |
Based on USEPA AP-42 Vol. 1 5th Edition, Table 11.9-4, Equation (1) |
|
Excavation |
0.0158 g s-1 |
Based on USEPA AP-42 Vol. 1 5th Edition, Section 13.2.4.3 |
|
Vehicle Movements on Unpaved Site Roads |
0.096 g s-1 |
Based on USEPA AP-42 Vol. 1 5th Edition, Section 13.2.2 |
|
Wind Erosion |
2.695 x 10-6 g s-1 m-2 |
Based on USEPA AP-42 Vol. 1 5th Edition, Table 11.9-4 |
It
was assumed that construction would take place over ten hours per day. The corresponding meteorological data has
thus been used as input to the FDM. The highest predicted TSP levels were
obtained and compared with the recommended 1-hour limit of 500 mgm-3.
The 24-hour TSP level was estimated by taking the average of 10 hours with worst-case daytime 1-hour average concentration and 14 hours with worst-case night time 1-hour average concentration. The predicted 24-hour TSP levels and the background daily TSP level were added together and compared with the AQO of 260 mgm-3.
Construction
dust impacts were modelled using the Fugitive Dust Model (FDM) with worst case
assumptions as input data and at ground level.
Predicted net and cumulative hourly and daily TSP levels at 1.5m above
local ground level at the identified SRs are shown in Table 34.3 below.
Table 444444.333333: Predicted
Hourly and Daily TSP Levels ( mgm-3) (1) at 1.5m above
local ground level
|
SRs |
Area |
Location |
Net Dust Impacts |
|
|
Maximum Hourly Average TSP Level |
Maximum Daily Average TSP Level |
|||
|
SR1 |
|
Village House |
355 |
94 |
|
SR2 |
Ngong Ping |
Village House |
310 |
107 |
|
SR3 |
|
Village House |
391 |
92 |
|
|
|
Dust
Criteria |
500 |
260 |
|
Notes: (2) Background TSP levels included in the results of daily average TSP (3)
Bold figure exceeds dust criteria |
||||
As
indicated in Table 34.2, all the predicted
24-hour TSP levels at the SRs will comply with the AQO criteria of 260 mgm-3 during
construction. However, in order to
minimise emissions from the site, further good site practice and appropriate
measures, such as those described in Section
5.1.1, could be implemented if needed. Construction is expected to be
completed within about 3 months. Only
short-term dust impact would result.
Since only a small number of items of construction equipment will be used, the overall exhaust emissions of SO2 and NO2 from the diesel-powered mechanical equipment of these plants are expected to be minimal.
No operation impacts are anticipate as a result of the stream diversion.
The only works programmed to be undertaken concurrently with the Stream Diversion Works is the site clearance and formation for the Cable Car and Theme Village.
The construction of the proposed Sewage Treatment Works and Sewerage at Ngong Ping will take place after the stream diversion.
This section outlines the potential noise impacts arising from the construction of the proposed stream diversion at Ngong Ping. A noise assessment has been undertaken to define the nature and scale of potential environmental impacts, specifically in terms of the effects in the vicinity of sensitive receivers. Construction phase impacts has been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels. No impacts are anticipated to occur during operation.
Construction activities that may generate noise impacts include:
· site clearance of the proposed stream alignment;
· rock-breaking in the proposed stream bed necessary in sections of the stream (as some of the rock head is close to the surface); and
· excavation of the proposed stream bed.
Ready mix or in-situ concrete/grouting will be used. This means that there will be no need for a concrete batching plant to be established on-site.
The extent of impacts depends on the distances between the work sites and the identified SRs, the construction methods employed and the number of plant used and vehicle movements.
The
main construction activities comprise construction of site clearance and
excavation of the diverted stream bed.
Construction activities for the Cable Car project are expected to be
undertaken during normal daytime working hours (i.e. 07:00 to 19:00 hours on
any day not being a Sunday or public holiday).
As described in Section 2 the
three phases of construction will not
overlap with each others, but will be
conducted sequentially. No rock
breaking is required between chainage 0 to 125, 260 to 300 or in the Phase I
construction (i.e. west side of proposed stream diversion). Rock breaking process is required between
chainage 125 to 260 due to the shallow rock head. Due to this project nature, two plant inventory lists i.e. with
and without Rock Breaker, have been established. The details are contained in Tables 34.4a and 34.4b5.
Table 444444.444444: Plant
Inventory (No Mitigation Measures)
[with Rock Breaker]
|
|
PME (Powered Mechanical Equipment) |
TM Ref. |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Breaker, excavator mounted (hydraulic) (1) |
CNP 028 |
1 |
122 |
122 |
|
|
|
|
Total SWL |
122 |
|
|
Excavator (Bucket Only) |
CNP 081 |
1 |
112 |
112 |
|
|
|
|
|
Total SWL |
112 |
|
|
Lorry |
CNP 141 |
1 |
112 |
112 |
|
|
|
|
|
Total SWL |
112 |
|
|
Concreting |
Crane, mobile |
CNP 048 |
1 |
112 |
112 |
|
|
|
|
Total SWL |
112 |
|
|
Concrete lorry mixer |
CNP 044 |
1 |
109 |
109 |
|
|
|
|
|
Total SWL |
109 |
|
|
Compactor, vibratory |
CNP 050 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
Notes:
1. Although two excavators will be used, the separation between
two will be always in the region of 50 metres.
Hence, when one of excavator is assessed against the noise criteria with
respect to the nearest receiver, the noise contribution from the other one will
be insignificant (less than 1dB(A)) and therefore only one number is assessed
above.
Table 444444.555555: Plant Inventory
(No Mitigation Measures) [without Rock Breaker]
|
|
PME (Powered Mechanical Equipment) |
TM Ref. |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Excavator |
CNP 081 |
1 |
112 |
112 |
|
|
|
|
Total SWL |
112 |
|
|
Lorry |
CNP 141 |
1 |
112 |
112 |
|
|
|
|
|
Total SWL |
112 |
|
|
Concreting |
Crane, mobile |
CNP 048 |
1 |
112 |
112 |
|
|
|
|
Total SWL |
112 |
|
|
Concrete lorry mixer |
CNP 044 |
1 |
109 |
109 |
|
|
|
|
|
Total SWL |
109 |
|
|
Compactor, vibratory |
CNP 050 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
Potential
noise impacts are predicted in Table 34.5 6 for the Sensitive Receivers shown in Figure 4.3.1.
Table 444444.666666: Noise
Impacts at Receiver (No mitigation Measures) - (Leq.30min dB(A))
|
SRs |
Area |
Receiver Description |
Noise Impacts from Stream Diversion
/dB(A) |
|
SR1* |
Ngong Ping |
Village house |
88 |
|
SR2 |
Village house |
85 |
|
|
SR3 |
Village house |
91 |
|
|
|
|
Noise Criteria |
75 |
Notes:
1. ‘*’ Receiver affected by Rock Breaking Plant
2. Bold figure exceeds noise criteria
3.
Façade effect is considered for all SRs
As
indicated in Table 34.4, the predicted
noise levels /dB(A) at the SRs will exceed the acceptable criteria of 75 dB(A)
during construction due to the close proximity of the works site, especially to
SR3. Noise mitigation measures are
therefore recommended (refer to Section
5.2.1) to reduce
noise impacts which will ensure the criteria will not be exceeded. Construction is expected to be completed within
about 3 months.
The construction task which generates the greatest impact is the ground excavation works. Once the trench has been excavated this will form a natural barrier and will protect the nearby residents from noise impacts.
This section outlines the potential waste impacts arising from the construction and operation of the proposed stream diversion at Ngong Ping and recommends an appropriate disposal strategy to alleviate the identified potential impacts. The recommended disposal strategy is based upon the waste management principle to reduce the amount of waste for disposal through the development of plans for waste avoidance, material re-use and recycling.
Mitigation measures are proposed to alleviate the impacts caused by the excavated materials and residual wastes during their handling, temporary storage on site, transportation and final disposal. The key task of the waste management assessment is to determine the material types, and, where possible, estimate the quantities of all solid waste arising during the construction for determining the most appropriate methods of treatment, handling and disposal. During the operational phase maintenance issues include the infrequent removal of silt from the stream bed.
Wastes which are likely to be generated during the construction of the stream course diversion include the following:
· vegetation and topsoil removed from site clearance around the course of the stream diversion although wherever possible this will be re-used on-site;
· Construction and Demolition (C&D) material;
· excavated materials; and
· municipal wastes.
During the construction phase, waste containers will be situated at a temporary storage area on site for general refuse. The material generated will be transported by truck to the official waste depot.
It is anticipated that the vegetation cleared will not require disposal off-site as it is made up of grassland and low shrub communities which are expected to generate very low amounts of vegetation and are anticipated to be fully utilised for landscaping purposes on site.
The construction of the stream diversion at Ngong Ping will require some breaking up of hard paving of roads which will result in approximately 20m3 of C&D material (only the wastes generated from the section of road that is directly over the proposed stream diversion is attributable to this project).
Construction and demolition materials arising from the construction, are expected to be minimal but may include:
· waste timber formwork;
· spent concrete and cement screening; and
· material and equipment wrappings.
It is anticipated that approximately 11,800m3 of excavated material will be removed for the proposed stream diversion, of which 8,100m3 will be soil, and 3,700m3 will be rock material.
It is the intention to reuse as much of the material as possible on site, and it is predicted that only a negligible quantity of unsuitable material (material which is waterlogged or not of a suitable grade) will have to be transported off-site to a public fill facility (public fill is the inert portion of C & D material, it includes debris, rubble, earth and concrete which is suitable for land reclamation and site formation). Approximately 1,650m3 of fill material is required on site (800m3 of rock for the gabion baskets, and 850m3 soil for general fill). Therefore there is expected to be about 7,200m3 of surplus material, and the intention is that this material is separately stockpiled on the adjacent proposed Ngong Ping Theme Village and Terminal Site for use during the Ngong Ping Theme Village and Terminal development.
Plant and vehicle servicing will likely be the primary source of chemical wastes during the construction period. The majority of chemical waste produced is therefore expected to consist of waste oils and solvents. However, since so few plant/vehicles shall be used (i.e. two excavators and one lorry), the volumes of chemical waste will be minimal. These will nonetheless be collected by a licensed waste haulier and sent to the Chemical Waste Treatment Centre at Tsing Yi.
Workers will generate municipal wastes such as food wastes, packaging and wastepaper. For estimating the quantity of municipal wastes, EPD’s average value 1.07kg/employee/day has been adopted (Monitoring of Municipal Solid Waste 1996, EPD (1997) Hong Kong Government).
The total volume of waste generated depends on the number of workers to be employed on site. It is anticipated that the number of workers and site staff to be employed at peak times is less than 10. Considering 6 working days per week, the amount of municipal waste generated will be around 65kg/week (maximum). Disposal will be the responsibility of the Contractor who shall, in accordance with general avoidance of nuisances measures (required under the Contract), remove material at such a frequency to avoid nuisance.
The estimated sewage arising from the workforce during the construction phase is estimated to be 6.0m3/day according to the Sewerage Manual (Part 1), DSD, 1995. Facilities such as mulching or chemical toilets (disposal off-site) shall be provided especially to ensure that no sewage is discharged directly into receiving environment. With the provision of such sanitary facilities and implementation of proper management and cleaning procedure, no adverse impact is anticipated on receiving environment.
Waste materials have the potential to cause adverse environmental impacts during generation, storage, transport and disposal. The following specific measures should be adopted during the construction stage of the project to minimise waste generation:
· segregate waste materials according to types to facilitate re-use and recycling;
· separate inert construction and demolition materials for dumping into public filling area or landfill site;
· Segregate different materials at source as far as practical;
· co-ordinate material deliveries to minimise storage times on site to avoid damage and producing waste material; and
· provide training to site staff in waste minimisation practices as part of the environmental management systems training (as part of the Code of Practice).
Wastes generated from site clearance shall be sorted and excavated topsoil segregated from roots for re-use in landscaping works, thus eliminating the need for off-site disposal.
The volume of material generated from the demolition will be minimal. A small section of road in the path of the proposed stream course diversion shall be demolished, and it is anticipated that this material be re-used on site in the gabion baskets, or stockpiled for use during the construction of the proposed Ngong Ping Terminal.
Excavated material shall be sorted on site, soil shall be used for landscaping, and rocks shall be reused on site in the gabion baskets that will line the bed of the diverted stream. It is anticipated that the majority of excavated material shall be reused on site or stockpiled for use during the construction of the proposed Ngong Ping Terminal. Should there however be any surplus excavated material that requires disposal at public filling areas, two possible locations have been identified. These are the public filling area in Tung Chung Development Phase 3A and the public fill stockpiling area at Mui Wo. Both were identified by the Secretary, Public Filling Committee (PFC) as possible locations available for dumping in accordance with the works programme.
Chemical waste, as defined in the Waste Disposal (Chemical Waste) (General) Regulation, will require appropriate and approved disposal scheme to eliminate the potential hazards as a result of inappropriate handling of these materials
Chemical wastes should be stored in a locked, fully bunded area which is impermeable to both water and the waste being stored. The waste storage area should also be covered to prevent rainfall from accumulating within the bunded areas. The bunded area must have a volume of either 110% of the largest container or 20% by volume of the chemical waste stored in that area. Appropriate spill absorption material should be stored near the storage area in order to clean up any minor spill events.
An appropriate disposal facility is the Chemical Waste Treatment Centre (CWTC) at Tsing Yi. If chemical wastes are to be generated, the contractor will need to register with EPD as a chemical waste producer and observe the requirements for chemical waste storage, labelling, transportation and disposal. The contractor will also need to consider the guidance in "A Guide to Chemical Waste Control Scheme: A Guide to the Registration of Chemical Waste Producers" and the "Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes". All chemical wastes should be collected from site by a licensed chemical waste collector.
If not appropriately managed, municipal wastes generated by site workers have a potential to cause impacts in terms of nuisance, insects and vermin. This may give rise to adverse environmental impacts for both site workers and site neighbours
A temporary refuse collection facilities should be set-up by the contractor and wastes should be stored in appropriate containers prior to collection and disposal. The temporary storage locations could be located at Ngong Ping.
Domestic effluent generated by the workforce will be directed to foul sewer or chemical toilets if foul sewers are not available.
The only waste expected to be generated during the operational phase is silt that could be deposited on the stream bed. This shall be removed by DSD staff during routine (albeit infrequent) maintenance works.
This section outlines the potential water quality impacts arising from the construction and operation of the proposed stream diversion at Ngong Ping. A water quality assessment has been undertaken to define the nature and scale of potential environmental impacts, specifically in terms of the effects in the vicinity of sensitive receivers. Both construction and operational phase impacts have been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels.
Existing pollution sources within the Study Site are generally related to the domestic effluents generated by the Ngong Ping community and associated village houses. Stream diversion requires various activities which could potentially affect the water quality and impact on the water sensitive receivers. These are primarily:
· the excavation works that may lead to sedimentation and reduced water quality (higher amount of suspended solids);
· wastewater generated by workforce during construction;
· the construction works which have the potential to cause spillages into the receiving waters (such as fuels and chemicals) during construction; and
· maintenance issues including disposal of silt from the streambed.
Potential water quality impacts primarily relate to the un-controlled discharge of sediments/ silts during the improvement works. The works are expected to be undertaken during the dry season i.e. during a period of low flow, and as such any sediments/ silts would unlikely to be conveyed from their source. This minimises the pollution potential and in addition there will be the same level of pollution control exerted for the stream course construction works as for all other aspects of the Cable Car Project.
As the generation of waste-water is anticipated to be minimal and controlled (i.e. toilets provided for workforce, pollution control measures in place to avoid off-site run-off etc.) during construction, impacts are thus considered to be minor.
Operational activities from maintenance of the water course have the potential to affect the stream environment. It is anticipated that these activities will fairly infrequent. Silt would be removed as required by DSD’s maintenance requirements.
It should be stressed that rather than the stream diversion works having a negative impact on the water an improvement in water quality is anticipated. The profile of the stream course will include gentle sloping sides and meanders to avoid stagnation, encourage flow and to create areas of habitat interest. The water quality of the stream course will also be greatly improved due to the reduction in point and non-point source pollution loads under the auspices of the Ngong Ping STP in 2007. MTR proposes to facilitate advance connection of the septic tank overflows from the village houses located directly adjacent to the proposed stream diversion to expedite improvement to water quality.
This section outlines the potential ecological impacts arising from the construction and operation of the proposed stream diversion at Ngong Ping. An ecological assessment has been undertaken to define the nature and scale of potential environmental impacts, specifically in terms of the effects on sensitive receivers. Both construction and operational phase impacts have been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels.
The potential terrestrial ecological impacts
arising from the construction activities may include direct impacts due to
habitat loss (i.e. loss of woodland plantation and shrubland vegetation)
and indirect impacts due to construction activities such as increased human
activities or disturbance (including noise, air quality, water quality impacts,
increased risk of hill fires etc). Potential construction phase impacts may
arise from:
·
site clearance resulting in habitat loss;
·
site clearance resulting in fragmentation of habitat;
·
construction resulting in wastes, pollutants and excavated material that
may impacts on stream habitats by pollution, erosion and/ or sedimentation; and
·
disturbance to flora and fauna from human activities including
construction machinery, air quality from machinery and water quality from
run-off of exposed soil.
The impacts resulting from the construction and operation of the Stream Diversion Works include:
· habitat loss;
· fragmentation of habitat; and
· disturbance from construction activities.
Clearance of vegetation will be required for construction of the proposed stream. No rare tree species were identified from an ecological investigation and Tree Survey. The length of stream habitat disturbed will be approximately be 390m and the proposed stream diversion will see the creation of approximately 305m of stream in plantation, abandoned cultivated land and shrubland habitat. Approximately 250 trees will be cleared from the existing and diverted stream alignments.
Riparian vegetation surrounding the existing stream at Ngong Ping including plantation, shrubland, cultivation (including abandoned cultivation) and grasses. The length of riparian habitat disturbed will be a linear band approximately be 390m in length and 15m width (approximately 0.6ha). No rare flora species are recorded in the Study Area.
The
loss of natural stream habitat will impact fauna species. In particular populations of amphibians (e.g. Bbrown tTree fFrog, Asiatic painted frog)
will have loss of stream habitat which is likely to reduce the number of frog
species in the Ngong Ping area. Impacts
resulting from habitat loss on these species and habitats (diverted and existing streams) are
anticipated to be moderate to
high if mitigation measures are not implemented.
No known food plants are known to be located in the construction area for rare or endangered fauna species.
Minor fragmentation impacts are anticipated during construction. The proposed diverted stream will allow fauna movement down/up stream.
Disturbance
is an unavoidable impact of the construction process. Disturbance will
generally have insignificant impacts on mobile taxa, or taxa which do not have
highly specific habitat requirements, such as some birds, large mammals,
reptiles, and butterfly and dragonfly adults.). Disturbance to less mobile species including some amphibian
species (e.g.., Brown Tree Frog) are anticipated to be high if
mitigation measures are not implemented.
The
exposure of soil surfaces during construction will create the potential for
soil erosion and subsequent water quality and sedimentation impacts on stream
habitats. The receiving environments
are sensitive to water quality and sedimentation impacts particularly stream
habitats and associated flora and fauna species; particularly amphibian species such as the
Short-legged Toad Megophrys
brachykolos.
Table 34.6 7 indicates
the impacts to potential ecologically sensitive species and provides an
evaluation of impacts.
Table 444444.777777: Ecologically Sensitive Receivers
and Evaluation of Impacts
|
Species |
Record/ Location |
Habitat Requirement |
Predicted Impacts |
|
Turdus chrysolaus (Brown Thrush) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Centropus sinensis (Greater Coucal) |
Plantation in Ngong Ping |
Widespread in Hong Kong |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Cettia fortipes (Mountain Bush Warbler) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (noise) due to the mobility of the species. |
|
Ficedula ugimaki (Mugimaki Flycatcher) |
Observed at Ngong Ping (OAP, 2002). |
They can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Emberiza tristrami (Tristram’s Bunting) |
Observed at Ngong Ping (OAP, 2002). |
Can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Zoothera daunma (Whites’ Thrush) |
Observed in woodland, Ngong Ping (OAP, 2002). |
White’s Thrush can be found in many types of terrestrial habitats (Carey et al., 2001). |
Insignificant impacts are predicted as no nesting trees will require removal. The cable car structures are unlikely to cause disturbance (i.e. noise) due to the mobility of the species. |
|
Brown Tree Frog (Polypedates megacephalus) |
Present in the Ngong Ping Stream and adjacent habitats (Mott Connell, 2003) |
Common and abundant in many places. An extremely hardy species (Karson et al., 1998). |
Although hardy, |
|
Megophrys brachykolos (Short-legged Toad) |
Tadpoles were found in seasonal streams at Ngong Ping (OAP, 2002) and SWS feeder stream 4. |
Narrow habitat tolerance. Low to moderate mobility. |
Insignificant impacts are anticipated as the species is located outside the construction area. |
|
Philautus romeri (Romer’s Tree Frog) |
Tadpoles were found in seasonal streams at Ngong Ping SSSI. (OAP, 2002). |
Fairly narrow habitat tolerance. Low to moderate mobility. |
Insignificant impacts are anticipated as the species is located outside the construction area. |
|
Rana exilispinosa (Lesser Spiny Frog) |
Ngong Ping Stream ( |
Narrow habitat tolerance. Low to moderate mobility. |
The species has not been located in the vicinity of the stream diversion. Insignificant impacts are anticipated resulting from construction near the Ngong Ping stream and subsequent disturbance (sedimentation and pollutants). |
|
Chinemys reevesii (Reeves’ Terrapin) |
Observed in stream habitat, Ngong Ping (OAP, 2002). |
Fairly narrow habitat tolerance. Low to moderate mobility. |
Potential impacts may result from construction and subsequent disturbance (sedimentation and pollutants) without mitigation measures. |
|
Elaphe radiata (Copperhead Racer) |
Observed in grassland, Ngong Ping (OAP, 2002). |
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. Reptile species of relatively high mobility which can relocate to other areas. Feeding habitat will be disturbed. |
|
Achalinus rufescens (Rufous Burrowing Snake) |
Observed in plantation, woodland and shrubland, Ngong Ping (OAP, 2002) |
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. Reptile species of relatively high mobility which can relocate to other areas. Feeding habitat will be disturbed. |
|
Amphiesma stolatum (Buff Striped Keelback) |
Observed in stream habitat, Ngong Ping (OAP, 2002). |
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. Reptile species of relatively high mobility which can relocate to other areas. Feeding habitat will be disturbed. |
|
Oligodon cinereus (Golden Kuri Snake) |
Observed in grassland, Ngong Ping (OAP, 2002). |
Can be found in many types of terrestrial habitats. |
Insignificant impacts associated with construction. Reptile species of relatively high mobility which can relocate to other areas. Feeding habitat will be disturbed. |
The stream course which traverses the site of the Ngong Ping Terminal and Theme Village site is an ecologically sensitive receiver which will be potentially affected by operational activities. However, the operational impacts are not significant and will be positive in the long term providing that stream mitigation measures, rehabilitation and landscaping are undertaken.
Disturbance impacts incurred during the operational phase are associated with increased interaction human activities resulting in elevated noise levels and increased lighting. These impacts however are considered low considering the operation hours of the Cable Car System and opening times of the Theme Village, which will provide opportunities for nocturnal fauna breeding and feeding periods.
This section outlines the potential landscape and visual impacts arising from the construction and operation of the proposed stream diversion at Ngong Ping. An assessment has been undertaken to define the nature and scale of potential environmental impacts, specifically in terms of the effects on sensitive receivers. Both construction and operational phase impacts have been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels.
The particular landscape impacts arising from the selected stream realignment are predicted to include temporary and permanent landscape impacts during construction and from the permanent structure of the stream.
Temporary landscape impacts during construction, e.g. false work for structural elements and excavation of the new channel and culvert will require approximately 120 trees to be felled. Upon completion, all temporary works areas would be fully reinstated initially by grassing and subsequent through the planting of trees and shrubs.
The permanent structure of the stream will result in loss of plantation woodland and areas of low shrub encountered along the new alignment. The man-made appearance of the stream will potentially intrude visually on the surrounding landscape unless sensitively designed. Therefore, to help mitigate these impacts, it is proposed that the stream course will incorporate a planting reserve along the embankment and public footpath to permit compensatory tree planting. In addition, wherever possible, materials specified for the banks and bed of the stream, such as gabion mattresses, will accommodate soiling and grass planting to permit colonisation by grasses, herbs and shrubs.
Landscape and visual impacts from the stream diversion are provided in Table 4.8 and 4.9 respectively. The noted Landscape Character Units (LCU 12 and LCU 15) are those through which the stream course flows (the unit numbering is consistent and sequential to the Cable Car EIA LCU numbering).
Table 444444.888888: Summary
of Landscape Impacts (without mitigation)
|
Unit (LCU) |
Description |
Quality/ Sensitivity |
Magnitude of Change |
Impact |
Impact Significance |
|
LCU 12 |
Monastery and Village settlement with patchwork of orchards, vegetable plots, untended land and storage areas |
3 |
2 |
The existing stream course will be realigned. The main impacts will be loss of vegetation, wildlife habitats and potential visual intrusion of the artificial channel |
Moderate |
|
LCU 15 |
Relatively level area surrounded by small rocky knolls with numerous graves amidst mainly scrub and grass vegetation with some amenity roadside planting |
2 |
3 |
The existing meandering stream course will be realigned. The main impacts will be loss of vegetation, wildlife habitats and potential visual intrusion of the artificial channel. |
Moderate |
|
Note (0)
Nil (1)
Small (2)
Intermediate (3) Large |
|
||||
Table 444444.999999: Summary
of Visual Impacts
|
Visually Sensitive Receivers (VSRs) |
Typical Viewpoint |
Quality/ Sensitivity |
Magnitude of Change |
Impact |
Impact Significance |
|
Residential |
|
|
|
|
|
|
Ngong Ping Village houses |
Views from within the Village areas or monasteries are generally short due to the settlement being low lying and the screening effect of mature trees throughout the Ngong Ping plateau. |
3 |
0 |
Apart from a few Village houses on the western fringe of Ngong Ping, residents will not see the stream course. |
Negligible |
|
Po Lin Monastery |
3 |
0 |
Nil |
||
|
Lin Chi Temple |
3 |
0 |
Nil |
||
|
Public Areas |
|
|
|
|
|
|
Buddha Statue |
Clear panoramic views
over Ngong Ping plateau |
3 |
0 |
Stream will not be
visible due to buildings and trees. |
Nil |
|
Di Tan Platform |
Low lying relatively enclosed views |
3 |
0 |
Stream will not be visible due to buildings and trees. |
Nil |
|
Cable Car Passengers |
Panoramic views in all directions |
1 |
1 |
Momentary glimpse of stream only |
Slight |
|
Users of Lantau
Trail, Village footpaths, roads |
Generally short, low-level views |
3 |
3 |
Prolonged short range view for pedestrians |
Moderate |
|
Note (0)
Nil (1)
Small (2)
Intermediate (3) Large |
|
||||
The majority of the Ngong Ping Stream is relatively unobtrusive amongst the undergrowth in the more remote, undeveloped areas downstream and in the vicinity of the proposed Terminal and Theme Village development. It is most noticeable at junctions with local access roads and when it is channelled close to the main Ngong Ping development. The new alignment will follow the northern boundary of the Theme Village and will comprise sections of open channel.
A VSR group will include the local residents living nearby who are familiar with the existing stream and associated landscape, frequenting the lanes and tracks that cross the stream. Also a VSR group will be the tourists arriving by the Cable Car System during operation. The diverted stream will be clearly visible from the Cable Car gondolas as they cross over it just before arriving at the Ngong Ping Terminal. The man-made outline of the stream will be potentially visually obtrusive unless mitigation measures are implemented.
The construction works will require approximately 0.6ha. of vegetation to be removed from the existing stream and 0.4ha for the diverted stream. The impact of the construction and operation will be mitigated by the irregular design of the stream design since it is not a straight line.
The stream diversion will be a permanent feature in the western fringe of the Ngong Ping plateau with a net loss of vegetation within the stream ‘footprint’. The design of the proposed stream is intended to complement the surrounding environment. By so doing, the landscape impact of introducing the stream diversion into the relatively undeveloped village hinterland will be reduced and is considered to be small to moderate.
The main VSR group affected by the new stream alignment will be village residents and to some extent visitors exploring the area using the local lanes and paths. This group of VSRs will be closest to the stream diversion located along the north and west perimeter of the Cable Car Terminal and Theme Village Complex. The number of VSRs in this group is difficult to estimate but will include a relatively small number of residents and visitors to the adjacent village houses, visitors en route to the columbarium and adventurous tourists. The visual intrusion of a stream diversion into this traditional settlement pattern has the potential to create a visual impact for this VSR group. The stream diversion is not generally visible to the residents in Ngong Ping due to the low-lying topography, low-rise buildings and extensive intervening woodland.
The second main group of VSRs affected will be the Cable Car passengers who will look down on the stream course as the gondolas pass over. The number of VSRs will be very large. However, it is likely that the passengers will be distracted by other more interesting views upon arrival and departure at Ngong Ping. Nevertheless, it is important that the man-made elements of the stream are sensitively detailed to create a more natural appearance to the structure and avoid becoming the focus of viewers’ attention.
Hill walkers in the hills surrounding Ngong Ping cannot be readily quantified but should be noted as they have the clearest views of the stream diversion within the context of Ngong Ping plateau as well as within the more remote and visually sensitive mid-section of the route.
The large number of annual visitors to the Buddha and Po Lin Monastery cannot be readily quantified but should nevertheless be noted as the cable car terminal can be seen from the elevation of the Buddha statue platform.
The stream will be relatively low-lying, situated behind the Ngong Ping Theme Village and a belt of mature trees and offset from the key visual axis of the Monastery and Buddha. The site topography, proposed Theme Village and vegetation will generally screen the stream from most views within the heart of Ngong Ping.
The stream diversion location has been selected to one side of the settlement in a relatively unobtrusive location. With sensitive design it will not detract from the special landscape character and ambience of the Buddha and Monastery.
This section outlines the potential impacts to cultural heritage and archaeology arising from the construction and operation of the proposed stream diversion at Ngong Ping. A cultural heritage and archaeological assessment has been undertaken to define the nature and scale of potential impacts, specifically in terms of the effects in the vicinity of sensitive receivers. Both construction and operational phase impacts have been assessed and mitigation measures have been identified to determine whether residual impacts can be reduced to acceptable levels.
The Stream diversion requires various activities which could potentially affect archaeology and built heritage. These are primarily:
· excavation works that may lead to direct subsurface impacts on areas of archaeological potential;
· direct impacts on heritage resources: buildings, structures or and/or graves during the construction stage;
· indirect impacts on built heritage during construction; i.e. vibration damage;
· indirect visual and aesthetic impacts on heritage resources; and
· restriction of access to temples and shrines and potential interference with cultural activities at Po Lin Monastery.
·
Requirements for relocation of shrines.
There is no record of habitation at Ngong Ping prior to the construction of the first buildings associated with the Po Lin Monastery. The Po Lin or ‘precious lotus’ monastery was founded in 1905 by three monks. Prior to this the area was uninhabited. The monastery was officially inaugurated in 1928 (Rodwell). Original buildings associated with the monastery were simple hermitages built between 1909 and the 1930s; they were later replaced by new buildings including the Po Lin Monastery which opened in 1970. Today the monastery complex contains numerous religious buildings, residential units and associated shops and restaurants. However, there are references to cultivation of tea on the southern slopes of Lantau Peak in the late 1880s and 1890s. Hayes records an interview with a Tung Chung woman born in 1879 who picked tea at plantations in that area as a child. The plantations were apparently run by Chinese from outside the island (Hase, Hayes and Lu 1986)[1].
The following potential impacts are noted:
· paths providing access to the Columbarium may be disrupted;
· two shrines are located on the course of the proposed diversion which will require relocation; and
· there will be no direct impacts on any areas with archaeological potential.
The only potential impact to built heritage associated with either the construction or operational phase of the Project is the required relocation of two shrines located within the permanent works site boundary. There will be no other direct impact to built heritage as there were no recorded resources in the vicinity of the existing or proposed stream locations. Indirect impacts (above) have the potential to occur for both the construction and operational phases for Po Lin and Ngong Ping.
There will be no direct impacts on any areas with archaeological potential. However, there will be direct impacts on two shrines, which shall require relocation (under the supervision of a qualified Archaeologist/ Cultural Heritage specialist).
No adverse vibration impacts associated with the proposed Project are anticipated as all works areas are located at a sufficient distance from the monastery and associated structures.
There will be no adverse visual or aesthetic impacts to the built heritage associated with the proposed project as all works areas are located at a sufficient distance from the monastery and associated structures and are separated from them by wooded areas.
There will no permanent adverse access and usage impacts associated with the proposed project as all works areas are located at a sufficient distance from the monastery and associated structures. Footpath diversions shall be required to maintain access to the columbarium at all times, permanent diversions are included in the proposal and therefore no permanent access impacts are anticipated.
Village and Monastery representatives have
advised that there are no issues regarding the relocation of shrines 1B and 2C since they contain no ashes and are for
worshipping the Land God. It is
therefore not considered necessary to de-consecrate the site.
It is expected that dust levels will not exceed the specified criteria under the published Air Quality Objectives (EPD). However, as good site practice the following dust control measures are proposed to reduce dust impacts to even further . Dust control measures for construction activities associated with the earthworks for Stream Diversion Works are outlined below.
The recommended mitigation measures to reduce air quality impacts relating to the handling of materials during construction are:
· the height from which materials are dropped should be controlled to a minimum practical height to limit fugitive dust generation from unloading;
· any stockpiles of aggregate or spoil should be covered and water applied as determined by the Environmental Team Leader;
· water spray should be used during the handling of excavated material where dust is likely to be created; and
· limit number of operating plant to the minimum necessary to undertake the works.
The recommended mitigation measures to reduce air quality impacts relating to vehicle movements on unpaved site roads during construction are:
· every vehicle should be washed to remove any dusty materials from its body and wheels before leaving a construction site;
· the load on the vehicles should be covered entirely by clean impervious sheeting to ensure that the dusty materials do not leak from the vehicle; and
· vehicle speeds limited to 20 kph to reduce the traffic induced dust dispersion and re-suspension within the site
The recommended mitigation measures to reduce air quality impact relating to earthworks during construction are:
· the amount of exposed soil should be kept in minimal by re-vegetation of completed earthworks.
No adverse residual impacts are predicted for the diversion of the stream at Ngong Ping, and by adopting the above recommendations the cumulative air quality impacts of the works are considered to be negligible.
Air quality impacts resulting from the stream diversion are predicted not to exceed air quality criteria or impact on sensitive receivers (residences) without mitigation measures. Nonetheless the above measures are good site practice and will further improve air quality.
Good site practice and noise management can significantly reduce the impact of construction site activities on nearby SRs. The following package of measures should be followed during of construction:
· only well-maintained plant should be operated on-site and plant should be serviced regularly during the construction works;
· machines and plant that may be in intermittent use should be shut down between work periods or should be throttled down to a minimum;
· plant known to emit noise strongly in one direction, should, where possible, be orientated to direct noise away from the SRs;
· mobile plant should be sited as far away from SRs as possible; and
· material stockpiles and other structures should be effectively utilised, where practicable, to screen noise from on-site construction activities.
The Contractor may be able to obtain particular models of plant that are quieter than standards given in GW-TM. Benefits which can be achieved through this approach will depend on the details of the Contractor chosen methods of working. As it is considered too restrictive to define specific items of plant for the construction operations, it is more practical to specify an overall plant noise performance specification to apply to the total SWL of all plant on the site so that the Contractor is allowed some flexibility to select plant to suit his needs.
Quiet
plant is defined as PME whose actual SWL is less than the value specified in
GW-TM for the same piece of equipment.
Examples of SWLs for specific silenced PME taken from a British
Standard, namely Noise Control on Construction and Open Sites, BS 5228 : Part 1
: 1997, which are known to be used are given in Table 5.1. The noise
screening benefit for each item of plant considered in this assessment is
provided in Tables 5.2a 2 and
5.2b3.
Table 555555.111111: Sound
Power Levels for Specific Silenced PME
|
PME |
BS
5228 Table
no |
Ref
no |
SWL dB(A)
max |
|
Excavator |
C.3 |
97 |
105 |
|
Breaker,
excavator mounted (hydraulic) |
C.8 |
13 |
110 |
|
Concrete
Lorry Mixer |
C.6 |
35 |
100 |
|
Lorry |
C.9 |
27 |
105 |
|
Crane,
mobile |
C.7 |
118 |
99 |
Table 555555.222222: Plant Inventory
(Using Quiet Plant) [with Rock Breaker]
|
|
PME |
TM Ref. /BS5228 |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Breaker, excavator mounted (hydraulic)* |
C.8-13 |
1 |
110 |
110 |
|
|
|
|
Total SWL |
110 |
|
|
Excavator (Bucket Only)* |
C.3-97 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
|
|
Lorry* |
C.9-27 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
|
|
Concreting |
Crane, mobile* |
C.7-118 |
1 |
99 |
99 |
|
|
|
|
Total SWL |
99 |
|
|
Concrete lorry mixer* |
C.6-35 |
1 |
100 |
100 |
|
|
|
|
|
Total SWL |
100 |
|
|
Compactor, vibratory |
CNP 050 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
Note(s):
1. '*' denotes quiet alternative is used in
accordance with BS5228, 1997
Table 555555.333333: Plant Inventory (Using Quiet Plant) [without Rock Breaker]
|
|
PME |
TM Ref. /BS5228 |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Excavator* |
C.3-97 |
1 |
105 |
105 |
|
|
|
|
Total SWL |
105 |
|
|
Lorry* |
C.9-27 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
|
|
Concreting |
Crane, mobile* |
C.7-118 |
1 |
99 |
99 |
|
|
|
|
Total SWL |
99 |
|
|
Concrete lorry mixer* |
C.6-35 |
1 |
100 |
100 |
|
|
|
|
|
Total SWL |
100 |
|
|
Compactor, vibratory |
CNP 050 |
1 |
105 |
105 |
|
|
|
|
|
Total SWL |
105 |
Note(s):
1. '*' denotes quiet alternative is used in
accordance with BS5228, 1997
Movable barriers, quieter plant and working methods are recommended to reduce noise to acceptable levels.
Movable
barriers, which may be made off-site, can be very effective in screening noise
from particular items of plant when constructing the stream diversion
work. Along the proposed stream
alignment from chainage 50 - 150 and at a section perpendicular to the stream
at chainage 0, it is recommended that a 3m high noise barrier with a materials’
sound reduction index of at least 20 dB(A) (e.g. 20mm Marine Plywood) is
erected. The proposed noise barriers shall be installed as close to the noise
generating component of a PME (say 2m between PME and Barrier). According to Figure D.3 of BS 5228 Part I:
1997, the proposed noise barriers can
reduce noise levels by at least 10 dB(A). The noise screening benefit for each
item of plant considered in this assessment is provided in Tables 5.43a
and 5.53b.
Table 555555.444444a: Plant Inventory (Using Movable Noise
Barrier)[with Rock Breaker]
|
|
PME |
TM Ref. /BS5228 |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Breaker, excavator mounted (hydraulic)*# |
C.8-13 |
1 |
100 |
100 |
|
|
|
|
Total SWL |
100 |
|
|
Excavator*# |
C.3-97 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
|
|
Lorry*# |
C.9-27 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
|
|
Concreting |
Crane, mobile* |
C.7-118 |
1 |
99 |
99 |
|
|
|
|
Total SWL |
99 |
|
|
Concrete lorry mixer* |
C.6-35 |
1 |
100 |
100 |
|
|
|
|
|
Total SWL |
100 |
|
|
Compactor, vibratory# |
CNP 050 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
Note(s):
1. '*' denotes quiet alternative is used in
accordance with BS5228, 1997
2. '#' denotes the movable noise barrier is used
Table 555555.555555: Plant Inventory (Using Movable Noise Barrier)[without Rock
Breaker]
Table 5.3b Plant Inventory
(Using Movable Noise Barrier)[without Rock Breaker]
|
|
PME |
TM Ref. /BS5228 |
No. |
SWL/Unit, dB(A) |
Sub-SWL, dB(A) |
|
Site Foundation and Excavation |
Excavator*# |
C.3-97 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
|
Lorry*# |
C.9-27 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
|
|
Concreting |
Crane, mobile*# |
C.7-118 |
1 |
89 |
89 |
|
|
|
|
Total SWL |
89 |
|
|
Concrete lorry mixer*# |
C.6-35 |
1 |
90 |
90 |
|
|
|
|
|
Total SWL |
90 |
|
|
Compactor, vibratory# |
CNP 050 |
1 |
95 |
95 |
|
|
|
|
|
Total SWL |
95 |
Note(s):
1. '*' denotes quiet alternative is used in
accordance with BS5228, 1997
2. '#' denotes the movable noise barrier is used
With
the incorporation of movable barriers and the use of quiet plant (as described
in Tables 5.2a 2, 5.3 and
b and 5.3a 4 and
b 5.5 above) the noise impact, would be reduced as
shown in Table 5.46. The detailed calculation sheets are
presented in Tables C1-3 of Appendix
C.
Table 555555.666666: Noise
Impacts at Receiver (Using Quiet Plant and Noise Barriers) - (Leq.30min dB(A))
|
SRs |
Area |
Receiver Description |
Noise Impacts from Stream Diversion
/dB(A) |
|
SR1* |
Ngong Ping |
Village house |
66 |
|
SR2 |
Village house |
68 |
|
|
SR3 |
Village house |
74 |
|
|
|
|||
Notes:
1. ‘*’ Receiver affected by Rock Breaking Plant
2 Bold figure exceeds noise criteria
3. Façade effect is considered for all SRs
The results indicate that with the incorporation of quiet plant and the use of movable noise barriers, the noise impact associated with the construction of stream course diversion would fully comply with the daytime construction noise criterion.
No adverse residual impacts are predicted for the diversion of the stream at Ngong Ping.
Noise resulting from the stream diversion is predicted to exceed noise criteria and impact on sensitive receivers (residences) without mitigation measures. After implementing mitigation such as the use of quiet plant and erection of movable noise barrier, the noise criteria for this project can be achieved and all 15 dwellings will be protected.
The various waste management options can be categorized in terms of preference from an environmental viewpoint. The options considered to be more preferable have the least impacts and are more sustainable in the longer term. Hence, the hierarchy is as follows:
· avoidance and minimization, i.e. not generating waste through changing or improving practices and design;
· reuse of materials, thus avoiding disposal (generally with only limited reprocessing);
· recovery and recycling, thus avoiding disposal (although reprocessing may be required); and
· treatment and disposal, according to relevant laws, guidelines and good practice.
· The Contractor should consult the EPD on the final disposal of wastes.
This hierarchy has been used to evaluate waste management options, thus allowing maximum waste reduction and often reducing costs. Waste reduction measures have been be introduced at the design stage and should be carried through the construction activities, wherever possible, reusing excavated rock in the gabion baskets, reuse of surplus excavated rock and soil (by stockpiling it for use during the construction of the proposed Ngong Ping Terminal) by careful purchasing control, reuse of formwork and good site management. By reducing or eliminating over‑ordering of construction materials, waste is avoided and costs are reduced both in terms of purchasing of raw materials and in disposing of wastes.
Section 34.4 sets out recycling, storage, transportation and disposal measures
which are recommended to avoid or minimize potential adverse impacts associated
with waste arising from the proposed Stream Diversion. MTR’s Contractor should
incorporate these recommendations and site specific factors into a
comprehensive on‑site Waste Management Plan. Such a management plan should incorporate site specific
factors. A Disposal Plan will also need
to be developed detailing disposal sites for waste that cannot be recycled
on-site and adopting a similar system to the trip-ticketing system, to monitor
disposal, and thus prevent illegal dumping.
Permitted waste hauliers shall be used to collect and transport wastes to the disposal points. The following measures to minimise adverse impacts shall be instigated:
· Handle and store wastes in a manner which ensures that they are held securely without loss or leakage, thereby minimising the potential for pollution;
· Use waste hauliers authorised or licensed to collect specific category of waste;
· Remove wastes in a timely manner;
· Maintain and clean waste storage areas regularly;
· Minimise windblown litter and dust during transportation by either covering trucks or transporting wastes in enclosed containers;
· Obtain the necessary waste disposal permits from the appropriate authorities, if they are required;
· Dispose of waste at licensed waste disposal facilities; and
· Maintain records of the quantities of waste generated, recycled and disposed.
· Wetting the surface of the stockpiled soil with water to keep the surface wet especially during the dry season;
· Covering the stockpiled soil with sheets; and enclosure of the stockpiling areas.
· Separating surface water drainage system for the stockpiling area;
· Installation of silt traps for the surface water drainage system; and
· Covering stockpiled material with tarpaulins during heavy rainstorm.
· The Contractor shall recycle C&D material on‑site. Proper segregation of wastes on site will increase the feasibility of certain components of the waste stream by the recycling contractors.
· The use of wooden hoardings shall not be allowed except where noise barriers are needed, and then these shall be of 20mm thick wood/ply. Elsewhere alternative materials, which can be reused or recycled, for example, metal (aluminium, alloy etc) shall be used.
· Different areas of the worksite shall be designated for such segregation and storage wherever site conditions permit.
· Trip-ticket system should be established to monitor the disposal of C&D material and solid wastes at public filling facilities and landfills, and to control fly-tipping.
Containers used for the storage of chemical wastes shall:
· be suitable for the substance they are holding, resistant to corrosion, maintained in a good condition, and securely closed;
· have a capacity of less than 450 litres unless the specifications have been approved by the EPD; and
· display a label in English and Chinese in accordance with instructions prescribed in Schedule 2 of the Regulations.
The storage area for chemical wastes shall:
· be clearly labelled and used solely for the storage of chemical waste;
· be enclosed on at least 3 sides;
· have an impermeable floor and bunding, of capacity to accommodate 110% of the volume of the largest container or 20% by volume of the chemical waste stored in that area, whichever is the greatest;
· have adequate ventilation;
· be covered to prevent rainfall entering (water collected within the bund must be tested and disposed as chemical waste if necessary); and
· be arranged so that incompatible materials are adequately separated.
Disposal of chemical waste shall:
· register as chemical waste producer;
· be via a licensed waste collector; and
· be to a facility licensed to receive chemical waste, such as the Chemical Waste Treatment Facility which also offers a chemical waste collection service and can supply the necessary storage containers; or
· be a reuser of the waste, under approval from the EPD.
· General refuse shall be stored in enclosed bins or compaction units separate from C&D and chemical wastes. Waste collector shall be employed by the contractor to remove general refuse from the site, separately from C&D and chemical wastes, on a daily or every second day basis to minimise odour, pest and litter impacts. Burning of refuse on construction sites is prohibited by law.
·
A coordinatorco-ordinator for the
management of waste should be identified who shall prepare a Waste Management
Plan.
Mitigation measures should be undertaken to reduce minor water quality impacts. The following sections provide a summary of the mitigation measures proposed to be implemented to minimise potential environmental impacts resulting from stream diversion works.
The diversion and restitution of the Ngong Ping Stream aims to enhance its potential ecological value, through improvements to the banks (soft engineering) is seen as a long-term benefit to the area and the downstream stream habitats.
The
detailed design of stream enhancement works in this small section will utilise
a number of channel designs features and will focus on a soft engineering. The
proposed indicative design of the stream diversion is illustrated in Figure 21.3.
All wastewater generated on the Study site shall be collected, removed from site via a suitable and properly designed temporary drainage system and disposed of at a location and in a manner that will cause neither pollution nor nuisance.
The Contractor should construct, maintain, remove and reinstate, as necessary, temporary drainage works and take all other precautions necessary for the avoidance of damage by flooding and silt washed down from the works. He shall also provide adequate precautions to ensure that no spoil or debris of any kind is allowed to be pushed, washed down, fall or be deposited.
The Contractor shall not permit any sewage, wastewater or other effluent containing sand, cement, silt or any other suspended or dissolved material to flow from the site onto any adjoining land or allow any solid waste to be deposited anywhere within the Site or onto any adjoining land and shall have all such materials removed from the site.
The Contractor shall be responsible for temporary drainage, diverting or conducting of open streams or drains intercepted by any works and for reinstating these to their original courses on completion of the works.
The Contractor shall at all times ensure that all existing stream courses and drains within, and adjacent to the Site are kept safe and free from any debris and any excavated materials arising from the Works. The Contractor shall ensure that chemicals and concrete agitator washings are not deposited in watercourses.
All Contractor’s Equipment shall be designed and maintained to minimise the risk of silt and other contaminants being released into the water column or deposited in other than designated locations.
To reduce water quality impacts from construction sites the Contractor will endeavour to:
· reduce the amount of water used to dampen any surfaces or stockpiles;
· any liquid generated on-site should be treated and disposed of in accordance with the provisions of the Technical Memorandum (TM) on Standards for Effluents Discharged into Drainage, Sewerage, Inland and Coastal Waters and shall be acceptable to (MTR/DSD/WSD/EPD);
· all domestic effluent arising from the construction work force, any work camps, or canteen facilities should also be collected, treated and disposed of according to the provisions of the TM; and
· any special works areas which may be provided for material storage or mixing, should be surrounded by bunds and have drainage collection systems to contain any spillages.
The following are conditions for working within Water Gathering Grounds as specified by Water Supplies Department. They will apply, through the permit process, in totality to the Cable Car project including the stream diversion works.
For all works within Water Gathering Ground (WGG), the Contractor will be required to comply with the following conditions:
(a) All practical measures shall be taken to ensure that no pollution or siltation occurs to the catchment.
(b) No earth, building materials, fuel, soil or toxic materials or any other materials which may cause contamination to the WGG are allowed to be stockpiled on site.
(c) No storage and discharge of flammable or toxic solvents, petroleum oil or tar and other toxic substances shall be allowed within the WGG.
(d) Any spoil shall be reused wherever practical, in-situ and where unavoidable surplus material shall be removed from the WGGs as soon as practicable.
(e) Temporary drains with silt/grease traps shall be constructed at the boundary of the site prior to the commencement of any earthworks. The effluent from the drain shall comply with the standards of Group A Inland Waters as stipulated in the Technical Memorandum prepared by EPD on “Standards for Effluents Discharged into Drainage and Sewerage Systems, Inland and Coastal Waters”. This will specifically apply at the Ngong Ping Terminal.
(f) Regular cleaning of the silt/grease traps shall be carried out to ensure that they function properly at all times.
(g) All excavated or filled surfaces which have the risk of erosion shall always be protected from erosion.
(h) Facilities for washing the wheels of vehicles before leaving the site shall be provided.
(i) Any construction plant which causes pollution to catchwaters or catchment due to leakage of oil or fuel shall be removed off site immediately.
(j) Any soil contaminated with fuel leaked from plant shall be removed off site and the voids arising from removal of contaminated soil shall be replaced by suitable material to the approval of the Director of Water Supplies.
(k) Provision of temporary toilet facilities shall be subject to the approval of the Director of Water Supplies. All waste shall be cleared away daily and disposed of outside WGG. The toilet facilities shall not be less than 30 m from any watercourse.
(l) All mud and debris shall be removed from any Waterworks access roads and associated drainage systems.
(m) Any chemicals to be used including fertilizers, disinfectants and deodorants within the WGG shall be subject to the approval of the Director of Water Supplies.
(n) For drainage and sewerage diversions within or affecting WGG, the agreement of the Director of Water Supplies is also required.
(o) Use of pesticides is not allowed within WGG, use of fertilizers within WGG subject to WSD’s approval.
Disposal of chemical wastes should be carried out in the compliance with the Waste Disposal Ordinance. The Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes published under the Waste Disposal Ordinance details the requirements to deal with chemical wastes. General requirements include:
· suitable containers should be used to hold the chemical wastes to avoid leakage or spillage during storage, handling and transport; and
· chemical waste containers should be suitably labelled to notify and warn the personnel who are handling the wastes to avoid accidents.
Storage area should be selected at a safe location on site and adequate space should be allocated to the storage area.
Emergency plans and clean up procedures will need to provided by the Contractor recognising his specific working methods and construction programme, activities and sequences. Agreement must be sought prior to commencement of the construction work but the following principles should be considered. The emergency plans should include the procedures for:
· spill prevention and precaution;
· response actions; and
· spill clean up and disposal.
Spill prevention and precaution embraces good site practice and covers:
· good housekeeping practices;
· chemical storage requirements; and
· chemical transfer and transport.
Detailed response actions should be clearly stated in the emergency plans and training to implement the responses should be provided to all staff. Emergency response plans should cover both construction and operational phases. Emergency response plans will contain procedures, telephone numbers and actions/responses to “prevent an accident becoming an emergency”. The Emergency Response Plan and clean up procedure outlined the Tung Chung Cable Car EIA shall be adopted. Detailed emergency plans and clean up procedures shall be agreed between MTR/EPD/WSD before the commencement of the construction work.
It is proposed that the following measures be implemented:
· the stream diversion to be constructed and completed prior to connection of up-stream water supply to reduce construction (in particular sedimentation) impacts;
· best practice construction methods and measures outlined in the Project Profile should be implemented; and
· ecologically friendly design should be undertaken.
The operational water quality of the stream course in Ngong Ping will be greatly improved with the completion of the planned Ngong Ping Sewage Treatment plant and sewerage works.
No residual adverse impacts are expected as a result of construction of the proposed stream at Ngong Ping. The current construction programme for the Ngong Ping Sewage Treatment Plant matches that of the Cable Car EIA and assuming that all mitigation measures and precautions are taken for the construction of both projects no residual impacts are anticipated.
The stream course diversion will be of benefit in terms of water quality (and ecology) and will provide additional enhancement to the environs at Ngong Ping.
By implementation of the mitigation measures and adherence to the practice notes and codes of practice for work within the Country Park and Water Gathering Grounds, the water quality impacts are deemed to be acceptable. Inspections of the work sites and the stream course as part of the routine auditing of the works would be expected to be adequate for the protection of the water resources. However in the event of spillage or accidental discharges the emergency control plan would need to be implemented (with the agreement of MTR/EPD/WSD/DSD) and checked for effectiveness.
The construction of the stream course is anticipated to have benefits to the stream from the removal of contaminated sediment, increased drainage capacity and avoidance of flooding which will improve the water quality of the stream course.
Accrued benefits associated with the stream diversion and Theme Village Complex include earlier sewerage connection for some residential dwelling immediately to the North of the Diversion.
Mitigation measures should be undertaken to reduce impacts. The following section provides a summary of the mitigation measures proposed to be implemented to minimise potential environmental impacts resulting from stream diversion works.
· The restitution of the stream should take into consideration the potential presence (downstream) of amphibian and fish species.
· Construction/ diversion works should be planned to take place in the dry season if possible.
· Riparian vegetation should also be planted and maintained.
· Consultation with relevant community groups and relevant Government departments to ensure that the stream restitution is effective.
· Incorporation of pools (deeper areas), boulders and natural materials to provide habitat for fauna species.
· The diverted stream to be designed to have the same velocity of water entering and exiting the stream under normal operation.
· Revegetate areas of temporary vegetation loss.
· Reconstruct and revegetate the stream at Ngong Ping (refer to Section 5.5.3), taking account of improved water quality in future. The restitution of the stream should take into consideration the potential presence (downstream) of protected and rare amphibian species.
· A Fauna Relocation Plan (Appendix H) is proposed to avoid and mitigate impacts caused by habitat and vegetation loss.
· Water for construction purposes should not be sourced from the Ngong Ping Stream (or any natural watercourses).
· During construction, a suitably trained person shall be present to relocate any terrestrial fauna located in the construction area (including those that are rare or protected). If any additional species listed as rare or protected are confirmed present, additional field surveys specific for the listed species should be conducted before the resumption of construction.
· Noise resulting from the preparation for construction shall remove most faunal presence from the vicinity until construction has ceased, however it is recommended that a tap/ knock of trees prior to clearing should be undertaken to reduce the chance of faunal injury. If any fauna species are injured during construction, the species should be promptly treated by the nearest fauna carer or vet.
· Where topsoil and vegetation is stripped during construction, wherever possible, topsoil and vegetative matter will be stockpiled. Stockpiled material will be stabilised to prevent sediment generation and re-spread as part of landscaping and rehabilitation of disturbed areas following construction. Exposed soil shall be covered or the run-off diverted away from stream habitats if possible. Temporary silt traps or sedimentation pools should be considered.
· Cleared vegetation to be ‘chipped’ (where appropriate) and stored for use as mulch during site landscaping works and/or in surrounded vegetated areas susceptible to erosion.
A Fauna Relocation Plan (Appendix H) is proposed to avoid and mitigate impacts caused by habitat and vegetation loss.
· Prior to works commencing on site, a complete photographic record shall be obtained of the site.
· Workers shall not leave any litter on site. Litter shall not be burned on site but shall be removed off site. All surplus construction materials brought onto site shall be removed from site and daily clearance of general litter shall be undertaken. Particular care shall be taken with bottles, wire, polystyrene lunch boxes, plastic wrapping, cans and non-degradable materials. Waste from portable toilets will be taken off-site.
· Animals shall not be fed and no food shall be left for any animals and no pets of any type shall be allowed on any site. Workers shall not disturb birds and other animals.
· Watercourses shall not be polluted with soaps, detergents or excretion.
· Access to work sites to be restricted and signed to prohibit unauthorised entry and the construction area should be fenced. This will minimise disturbance to vegetation, including unauthorised clearing. There shall be no work outside of the designated sites.
· Restrict the passage of machinery outside the designated construction areas and a minimum number of machinery parking areas should be used and clearly designated.
There shall be regular cleaning and frequent watering of the construction sites during dry periods to avoid dust (as determined by the engineer), but attention should be paid to prevent washing waste materials off site.
The contractor shall provide for all necessary materials on site for emergency spill measures and shall be trained in emergency spill response.
The
proposed stream diversion will result in a net loss of stream habitat (i.e.
0.6ha)(a total of about 1ha including the stream diversion) or approximately
and 250 individual trees (generally common planted species). Residual impacts will be the loss of habitat and
displacement of a number of amphibian and reptile species. The residual impacts are
considered moderate. Compensation for the net loss of trees and stream
habitat is required to offset the net loss of trees and stream habitat. The habitat
provides breeding areas for a number of amphibian and reptile species.
Abandoned cultivation and plantation trees provide nesting areas for bird
species.
It
is recommended that compensatory planting be undertaken at the Ngong Ping
Plateau to offset the net loss of trees cleared and the stream habitat
disturbed. A Compensatory Plannting Plan (Appendix G) has been developed to ensure that residual impacts are
fully compensated. Figures
5.1-5.3 show some of the proposed
locations for planting. The plan details objectives of planting, species
and locations for planting and recommended procedures for compensatory
planting. The Plan will be subject to the outcomes of consultation with
relevant community groups and relevant Government departments (AFCD). This
consultation would ensure that the planting is effective and that the diverted
stream planting is effective.
The species of conservation interest appear to be widely distributed in the wider survey area and do not appear confined to any single location. The exception to this is amphibians that have relative low mobilities and may be impacted upon by sedimentation and contamination. Although the stream at Ngong Ping appears to have poor water quality, particular care in the design and construction of the Ngong Ping Terminal is necessary.
Construction of the proposed Project must be conducted in an appropriately ecologically sensitive manner, with particular attention given to avoidance or minimisation of disturbance through appropriate works scheduling and responsible works area maintenance. Many streams and forest habitats in the Study Area are of particularly high ecological value due to a low level of anthropogenic disturbance, and it is crucial that impacts to these highly sensitive habitats are avoided or minimised wherever possible. The loss of ecologically valuable habitat should be mitigated to the fullest possible extent.
Providing that the stream is appropriately restored, and that mitigation and compensatory measures are implemented (including water quality mitigation measures to prevent sedimentation, erosion etc.), no significant impacts are anticipated.
Mitigation measures should be undertaken to reduce impacts. The following section provides a summary of the mitigation measures proposed to be implemented to minimise potential environmental impacts resulting from stream diversion works.
Any trees identified as affected by the works will be first considered for transplanting to nearby suitable sites. Felling will only be considered as a last resort. The feasibility of transplanting will depend on a number of factors such as size, health and species of the tree as well as the condition of the local terrain. Adequate time (a minimum of 4 months) should be allowed for preparing trees for transplanting.
Trees to be retained within or adjacent to works areas will be carefully protected by strong hoarding and if necessary additional protection to individual tree trunks to avoid damage by machinery. The hoarding will also prevent contractors compacting soil around tree roots or dumping materials.
The topsoil layer removed during construction of the stream course should be saved and carefully stored to one side of the works area for reuse upon completion to help backfill gabion mattresses and embankments.
The existing species mix colonising the existing stream banks have been recorded. Together with tree planting to the footpath to be formed alongside the new stream it is proposed that a complementary mix of indigenous shrub and herb species is specified for reinstating the embankments and colonising the gabion mattresses. In association with the proposed planting for the Cable Car Terminal and Theme Village in general it is intended to enrich the flora species diversity for the new stream. Species for compensatory planting works is provided in Appendix G which will be of value for birds, butterflies and bats. It is noted that native trees typically have a higher ecological value as food and shelter for animals, and will be preferred to exotic species when finalising the plant species mix.
The
new stream course will form a strategic ‘edge’ to the proposed Terminal and
Theme Village. This sensitive interface
between the existing Village landscape and the new development deserves careful
treatment. The primary function is to
provide a safe and effective means of diverting the existing stream and prevent
future flooding to surrounding areas. The landscape design principles for the
stream course are further discussed below and illustrated in Figure 55.24 and 5.5.
Trees with non-aggressive root systems will be used to avoid damage to the stream structure and where necessary root guards can be installed. The replanting of trees is an important landscape feature which will achieve a number of important objectives, namely:
· compensate for trees to be removed to construct the new stream course;
· provide welcome shade to the footpath;
· Enhance the overall landscape amenity of the footpath and perimeter of the Theme Village development; and
· Provide a strategic partial screen to the Theme Village for nearby Village houses.
It is recommended that informal planting be undertaken, consisting of irregularly spaced and positioned trees, shrubs and grasses, to blend in with the adjacent woodlands.
The overall form of the stream will be created by banks, a base of gabion mattress and some rip-rap. In order to create a more natural meandering outline to the stream and avoid an obviously engineered profile it is proposed that the gabions be staggered and interspersed with groups of natural boulders and riffles. After installation the gabions can be backfilled with soil and grassed to provide a stable base for re-colonisation by adjacent shrub, vines and herb species. Indicative design proposals are shown in the figures. These are subject to further design development which it is proposed will be undertaken with AFCD and the Green Groups but which will be subject to DSD’s approval.
The
anticipated residual landscape and visual impacts, i.e. impacts remaining after
the above mitigation measures have been implemented, are summarised in Table 5.67.
Table 555555.7777775.9: Summary
of Residual Landscape and Visual Impacts
|
Landscape Character Unit (LCU) Visually Sensitive Receivers (VSRs) |
Sources of Impact |
Magnitude of Change |
Landscape Quality/ Sensitivity Visual Quality/ Sensitivity |
Mitigation Measures |
Residual impact after Implementation of
Mitigation Measures |
|||
|
Construction (with mitigation) |
Operation (with mitigation) |
Construction |
Operation |
|||||
|
LCU 12 |
Loss of vegetation to
accommodate new alignment of stream |
Intermediate |
Small |
Medium |
Partial reinstatement
by compensatory tree, shrub and grass planting to embankment and use of
sensitive materials such as gabions to allow re-colonisation of water’s edge
by shrubs, vines and herbs. Use of
natural boulders to soften engineered stream profile. |
Moderate |
Slight / Moderate |
|
|
LCU 15 |
Loss of vegetation to
accommodate new alignment of stream |
Large |
Intermediate |
Low |
Partial reinstatement
by compensatory tree, shrub and grass planting to embankment and use of
sensitive materials such as gabions to allow re-colonisation of water’s edge
by shrubs, vines and herbs. Use of
natural boulders to soften engineered stream profile. |
Moderate |
Slight / Moderate |
|
|
Ngong Ping Residential Village houses Po Lin Monastery Lin Chi Temple Public Areas Buddha Statue Di Tan Platform Cable Car Passengers Users of Lantau
Trail, Village footpaths, roads |
The realigned stream
is in low-lying terrain not generally visible beyond immediate Village
houses. General loss of vegetation,
particularly removal of trees for construction along the proposed alignment
is potentially the most obvious visual impact. The visual intrusion of the man-made stream would be more
apparent at close range for local Villagers and pedestrians using the local
lanes and adjacent access roads. |
Negligible Nil Nil Nil Nil Not applicable Large |
Negligible Nil Nil Nil Nil Small Intermediate |
High High High High High Low Low |
Stream to be designed
using materials which will encourage recolonisation by plants. Associated footpath
to have irregular tree, shrub and grass planting to soften profile of
structure and elevation of Theme Village / Terminal building when viewed from
Village areas. Natural boulders to
be incorporated into stream bed and embankments to create more natural
appearance. |
Negligible Nil Nil Nil Nil Not applicable Moderate |
Negligible Nil Nil Nil Nil Slight Slight / Moderate |
|
The realignment of the stream course to accommodate the construction of the Cable Car Terminal and Theme Village Complex will result in loss of natural topography, flora and fauna associated with the meandering stream. The majority of the stream is located on the western fringe of the Ngong Ping development. Nevertheless, the new stream alignment will be a prominent landscape feature once the Cable Car is in operation. It is therefore important that the man-made stream is carefully and sensitively detailed to reduce the visual intrusion and maximise the opportunity for plant and wildlife re-colonisation. A number of practical measures are discussed and illustrated above which once in place should ensure the new stream course is an asset to the proposed development and will not detract from the surrounding environment.
Mitigation is
required for the shrines affected by the stream works. The shrines shall be relocated to a suitable
location in Ngong Ping. Discussion with
AMO and the concerned Ngong Ping residents will be undertaken to ensure that
impacts are minimisedSince the two shrines directly impacted shall be
relocated or rebuilt no mitigation measures shall be required. However discussion shall be undertaken with the shrine owners and concerned parties and agreement reached on the location and method of relocation or reconstruction of the shrines.
At shrine three the No other mmitigation shall comprise monitoring of the condition of the shrine and making good any
damage.is required as
there will be no impacts on areas of archaeological potential.
No residual adverse impacts are expected as a result of constructing or operating phase of the stream diversion.
No archaeological
sites have been recorded in areas, which will be directly impacted by the
proposed project. The stream diversion
is therefore not anticipated to impact on the archaeology at Ngong Ping.
The only built
heritage sites recorded in areas that will be directly impacted by the proposed
project are two shrines. The anticipated impact on the shrines is their
relocation and preliminary agreement has been given by village and monastery
representatives for relocation.. No
other impacts are anticipated.
As mentioned in the EIA for the
Tung Chung Cable Car Project, the overall development will offer a unique
opportunity to present the culture and history to both local and overseas
visitors. It should be emphasised that
the cable car project which the stream works will facilitate is will be
beneficial to the heritage of the area and that the majority of impacts can be
seen as positive.No archaeological sites have been recorded in areas
which will be directly impacted by the proposed project. The stream diversion
is therefore not anticipated to impact the archaeological at Ngong Ping.
The only built
heritage sites recorded in areas which will be directly impacted by the
proposed project are two shrines. The anticipated impact on the shrines is
their relocation. No other impacts are
anticipated.
As mentioned in
the EIA for the Tung Chung Cable Car Project, the overall development will
offer a unique opportunity to present the culture and history to both local and
overseas visitors. It should be
emphasised that the cable car project which the stream works will facilitate is
will be beneficial to the heritage of the area and that the majority of impacts
can be seen as positive
The overall objective of the Cable Car Project is to ensure the intertwined objectives of safety, engineering requirements, environmental management, sustainability and tourism are all met. In order to do this, the EIA and proposed Stream Diversion have taken into account views of concerned parties and discussions have been held with various entities such as the Green and Conservation Groups, operators of similar systems (e.g. Skyrail an Australian owned company who operate the Smithfield to Kuranda cableway and who are party to the MTRC franchise agreement with Government) as well as the suppliers of equipment and local Contractors who have provided solutions to working within the difficult and often hazardous terrain of the Lantau North Country Park. Discussions with the Green Groups (Conservancy Association, Green Lantau Association, Friends of the Earth, Kadoorie Farm and Worldwide Life Fund) have all reviewed and commented on Working Papers, the Draft EIA report and the stream diversion information, their feedback has resulted in a more robust Study.
The following consultation has been carried out as part of the design development for the Cable Car Project and the proposed stream diversion:
|
· Informal presentation on the Cable Car Project and discussion of the Project with Green and Conservation Groups. |
22nd August 2002 |
|
|
|
|
· Consultation with Green and Conservation Groups on the Draft EIA (Chapters 1 and 2). |
27th September 2002 |
|
|
|
|
· Circulation of Briefing Paper on Pylon Locations and Emergency Rescue Plan to Green and Conservation Groups. |
2nd December 2002 |
|
|
|
|
· Circulation of Draft EIA Report to Green and Conservation Groups. |
2nd January 2002 |
|
|
|
|
· EIA advertised for public consultation. |
29th March 2003 |
|
|
|
|
· Circulation of EIA Executive Summary (during public review period). |
2nd April 2003 |
|
|
|
|
· Discussion on stream diversion. |
2nd April 2003 |
|
|
|
|
· Project design development shows it is not possible to maintain the stream diversion. |
14th - 25th March 2003 |
|
|
|
|
· Issue of a draft stream diversion report to Report to Green and Conservation Groups. |
12th May 2003 |
|
|
|
|
· Issue of a revised stream diversion report to Report to Green and Conservation Groups. |
|
|
|
|
|
· Stream information and field walk with Green Lantau Association. |
22nd June |
This
section is complimentary to the “Code of Practice for the Works of Tung Chung
Cable Car Project” (October 2002), and the EM&A Manual prepared for the
Tung Chung Cable Car Project. With
regard to the proposed stream diversion works particular attention is drawn to
the waste, water, ecological, landscape and visual impacts for the proposed
stream diversion. Mitigation measures
for all environmental impacts are detailed in will follow those given in Section 14 of the Approved EIA for the Tung Cable Car EIA (Study Brief No. ESB-068/2001). the Implementation
Schedule attached as Appendix I
.
MTR’s Contractor is required to produce a comprehensive Waste Management Plan and a Waste Disposal Plan detailing recycling, storage, transportation and disposal. Waste shall be reused on site as far as practicable in order to minimise the impacts of waste disposal. It is anticipated that the majority of excavated material shall be reused on site or stockpiled for use during the construction of the proposed Ngong Ping Terminal. Excavated material shall be sorted on site, soil shall be used for landscaping, and rocks shall be reused on site for the gabion baskets and rip-rap. Detailed records shall be kept of waste produced in order to monitor disposal, and these records shall be audited. Regular site inspections shall be carried out to ensure implementation of the mitigation measures.
Sedimentation impacts are the main concern with regard to water quality, and these may occur during rainfall events, so the works should, if possible, take place during the dry season. MTR’s contractor shall implement the mitigation measures as detailed in the implementation schedule in order to minimise adverse impacts on water quality as a result of the proposed works.
Auditing shall be carried out, including inspections of stream courses and drains, to ensure successful implementation of mitigation measures during construction.
Construction of the proposed Project must be conducted in an appropriately ecologically sensitive manner, with particular attention given to avoidance or minimisation of disturbance through appropriate works scheduling and responsible works area maintenance.
Mitigation measures should be undertaken to reduce impacts or the proposed works. Careful monitoring of the proposed mitigation measures by an Environmental Specialist who is preferably be a member of the Hong Kong Institute of Environmental Impact Assessment with a minimum of 5 years experience of work in Hong Kong and preferably has a suitable background in natural history and a professional qualification in terrestrial ecology or botany, is required to assess the effectiveness of mitigation measures.
Mitigation measures detailed in the Implementation Schedule will be fully implemented. The compensatory planting and tree planting areas shall be visually inspected during the regular site audits to ensure survival and healthy growth of the vegetation.
This Project Profile utilised information from the following approved EIAs.
Applicant (MTR) was informed on 27 March 2003 of the suitability of the report for public inspection.
The Report is exhibited for public to comment from 29 March 2003 to 27 April.
Approved with conditions on 9 June 2003.
The Tung Chung Cable Car EIA Report provides key information on the existing environment at Ngong Ping including the identification of sensitive receivers and the assessment and evaluation of potential impacts.
The Ngong Ping stream is within the Study Area boundary of an Government approved Ecological Baseline Study (BMT, 2002) which provided the basis for the approved Tung Chung Cable Car EIA (Mott Connell, 2003). The ecology baseline study was undertaken for 9 months for both wet and dry season in 2002-2003.
This Project Profile utilises information from the approved EIA to provide baseline data and determine ecological impacts. Acceptable impacts on ecology were predicted from the construction of the Cable Car terminal at Ngong Ping.
Applicant was informed on 7 May 2002 of the suitability of the report for public inspection.
Report was exhibited for the public to comment from 14 May 2002 to 12 June 2002.
Approved with conditions on 4 July 2002
The Ngong Ping Sewage Treatment Works and Sewerage EIA was undertaken with an overlapping Study Area boundary which is located adjacent to the proposed stream diversion (and Cable Car Terminal and Theme Village). The report investigated the potential environmental impacts for the construction and operation of the Sewage Treatment Plant (STP). Environmental aspects including air quality noise, waste, water, landscape and visual, ecology, fisheries and cultural heritage were assessed in detail. In particular the existing environment at Ngong Ping (within the Study Area boundary) is the same and sensitive receivers are comparable.
Terrestrial
ecological surveys were carried out from July 2001 to mid-April 2002, covering
both dry and wet seasons, in accordance with the EIA Study Brief
ESB-074/2001. Limited impacts on
ecology were predicted from the construction of the sewage treatment works.
Provided that good practice for controlling surface runoff is employed and
enforced, and earthworks can be suspended for the section of sewer close the
stream where the Romer's Tree Frog was found during the breeding season of the
frog (March to September), no residual impacts are were anticipated.
Air quality impacts resulting
from the stream diversion are predicted not to exceed air quality criteria or
impact on sensitive receivers (residences) without mitigation measures.
Nonetheless the above measures are good site practice and will further improve
air quality.
Noise resulting from the stream
diversion is predicted to exceed noise criteria and impact on sensitive
receivers (residences) without mitigation measures. After implementing
mitigation such as the use of quiet plant and erection of movable noise
barrier, the noise criteria for this project can be achieved and all 15
dwellings will be protected.
The stream course diversion will
be of benefit in terms of water quality (and ecology) and will provide
additional enhancement to the environs at Ngong Ping.
By implementation of the
mitigation measures and adherence to the practice notes and codes of practice
for work within the Country Park and Water Gathering Grounds, the water quality
impacts are deemed to be acceptable. Inspections of the work sites and the
stream course as part of the routine auditing of the works would be expected to
be adequate for the protection of the water resources. However in the event of
spillage or accidental discharges the emergency control plan would need to be
implemented (with the agreement of MTR/EPD/WSD/DSD) and checked for
effectiveness.
The construction of the stream
course is anticipated to have benefits to the stream from the removal of
contaminated sediment, increased drainage capacity and avoidance of flooding
which will improve the water quality of the stream course.
Accrued benefits associated with
the stream diversion and Theme Village Complex include earlier sewerage
connection for some residential dwelling immediately to the North of the
Diversion.
The species of conservation
interest appear to be widely distributed in the wider survey area and do not
appear confined to any single location. The exception to this is amphibians
that have relative low mobilities and may be impacted upon by sedimentation and
contamination. Although the stream at Ngong
Ping appears to have poor water quality, particular care in the design and
construction of the Ngong Ping Terminal is necessary.
Construction of the proposed
Project must be conducted in an appropriately ecologically sensitive manner,
with particular attention given to avoidance or minimisation of disturbance
through appropriate works scheduling and responsible works area maintenance.
Many streams and forest habitats in the Study Area are of particularly high
ecological value due to a low level of anthropogenic disturbance, and it is
crucial that impacts to these highly sensitive habitats are avoided or
minimised wherever possible. The loss of ecologically valuable habitat should
be mitigated to the fullest possible extent.
Providing that the stream is
appropriately restored, and that mitigation and compensatory measures are
implemented (including water quality mitigation measures to prevent
sedimentation, erosion etc.), no significant impacts are anticipated.
The realignment of the stream
course to accommodate the construction of the Cable Car Terminal and Theme
Village Complex will result in loss of natural topography, flora and fauna
associated with the meandering stream.
The majority of the stream is located on the western fringe of the Ngong
Ping development. Nevertheless, the new stream alignment will be a prominent
landscape feature once the Cable Car is in operation. It is therefore important that the man-made stream is carefully
and sensitively detailed to reduce the visual intrusion and maximise the
opportunity for plant and wildlife re-colonisation. A number of practical measures are discussed and illustrated
above which once in place should ensure the new stream course is an asset to
the proposed development and will not detract from the surrounding environment.
No archaeological sites have been
recorded in areas,
which will be directly
impacted by the proposed project. The stream diversion is therefore
not anticipated to impact on the archaeologarchaeologyical at Ngong Ping.
The only built heritage sites
recorded in areas that
will be directly impacted by the proposed project are two shrines. The anticipated impact on the
shrines is their relocation and preliminary agreement has been given by village and monastery representatives for relocation.. No other
impacts are anticipated.
As mentioned in the EIA for the
Tung Chung Cable Car Project, the overall development will offer a unique
opportunity to present the culture and history to both local and overseas
visitors. It should be emphasised that
the cable car project which the stream works will facilitate is will be
beneficial to the heritage of the area and that the majority of impacts can be
seen as positive.
BMT (2002), Agreement No. HKI
1/2002 Tung Chung Cable Car Project:
Ecological Baseline Survey.
Green Lantau Association
(Unknown), A
Conservation Strategy For Lantau (Website accessed February
2003)
http://pangyiukai.net/devstrat1.htm
Hau, B.C.H. and So, K.K.Y (2002).
Forest Restoration for biodiversity
Conservation on degraded hillsides in Hong Kong, China. In Anon. 2002.
Abstracts of the Chinese Academy of Sciences Workshop on Ecosystem Succession
Theory and Practice of Ecological Restoration, 27-29 December 2002, Guangzhou,
China, South China Institute of Botany, CAS.
Hase P.H., Hayes J.W. and Lu K.C.
(1986), Traditional Tea Growing Areas in
the New Territories In RAS, Vol 24: 261-281.
Karsen, S.J. Lau, M.W.N. and
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