1. Introduction
1.1
At
present aviation fuel is delivered to the Hong Kong International Airport via
an existing temporary Aviation Fuel Receiving Facility sited off Sha Chau. This
facility is located within the Lung Kwu Chau and Sha Chau Marine Park. The facility does not have the capacity
to meet the forecast demand for aviation fuel during the operational lifetime
of the airport. In addition, the
Airport Authority Hong Kong has a commitment to have a permanent facility, whereupon the existing facility would
cease to be used routinely and would be kept for emergency back-up only.
1.2
A
preferred location for the strategically important permanent facility has been
identified on existing reclaimed land at Tuen Mun Area 38, see Figure 1.
1.3
The
project is deemed to be a designated project under the terms of the
Environmental Impact Assessment Ordinance and, as such, an Environmental Impact
Assessment has been undertaken to support an application for an Environmental
Permit. The key issues, findings and conclusions are presented in this
Executive Summary.
2. Site
Selection and Comparison of Alternatives
2.1
The
search for a suitable site for the permanent facility and related comparative
assessment has taken place over a
10 year period in full consultation with the regulatory authorities.
2.2 A
number of potential sites including Sham Shui Kok, Sham Wat, Bluff Point, Kau
Yi Chau, East of Sokos, Tsing Yi and those near the airport and in the Tuen Mun
area, have been considered. The
proposed location at Tuen Mun Area 38 is considered to be the environmentally
most preferred of all these sites.
This site is in a heavily industrialised setting, adjacent to Castle
Peak Power Station and Shui Wing Steel Mill. It compares favourably with the
above sites, most of which are more ecologically sensitive because of the
associated required reclamation. Siting the facility in Tuen Mun Area 38 avoids
the need for land reclamation.
2.3 Aviation
fuel would be transported from the proposed jetty via a tank farm at Tuen Mun
Area 38 to the airport by means of twin subsea pipelines. Alternative routings
for this pipeline have been compared.
The options include one in which construction of a pipeline ties into
the Aviation Fuel Receiving Facility at Sha Chau, in order to make use of the
existing twin subsea pipelines from Sha Chau to the airport. Another option comprises a longer route
involving a completely new pipeline running directly between Tuen Mun Area 38
and the airport. The
environmentally preferred choice has been determined to be that which ties into
the facility at Sha Chau.
2.4
The
requirements for dredging and pipelaying are substantially reduced if continued
use is made of the existing pipelines, whose lifespan is sufficient to meet the
need for the airport’s anticipated operational life. Disturbance to dolphins during construction would also be
lessened and there are benefits for operational aspects. Usage of this pipeline will eliminate
the need for routine offloading of aviation fuel at the back up facility at Sha
Chau (to flush the pipeline and maintain the aviation fuel in an acceptable
state). However, about 400m
of twin pipelines will need to be constructed within the Marine Park.
3.
Description of the Project
3.1
The
permanent facility at Tuen Mun Area 38 will consist of the following major
elements:
¨
a jetty
to accommodate aviation fuel tankers;
¨
a tank
farm for storage of aviation fuel;
¨
on-site
operational facilities including offices;
¨
twin
sub-sea pipelines to transfer the aviation fuel to the airport.
3.2
The planning,
design and construction of the project is programmed to take about 4 years,
with the commissioning date targetted for the end of 2005. The PAFF and its
surrounding area is shown in Figure 2.
3.3
Approximately
6.7 ha of land are required to house the aviation fuel tank farm and associated
facilities taking up a small part of Tuen Mun Area 38. The proposed site is zoned for
industrial use. The closest residential development Lung Kwu Tan is located
approximately 2 km away, and comprises low-rise village type housing. The nearest major population centre is
the Melody Garden Estate in Tuen Mun, some 3 kilometres distant.
3.4
The tank
farm will initially house four storage tanks each providing a storage capacity
of 35,000m3. Thereafter additional tanks would need to be
constructed to provide an ultimate design capacity of about 400,000m3. The tank farm will be provided with
bundwalls and contained drainage.
3.5
Other
tank farm facilities include an office building for administrative and security
control, leak detection instrumentation, fire fighting and emergency spill
equipment, workshops and basic infrastructure including roads,
telecommunications, drains, power supply and lighting.
3.6
Aviation
fuel will be offloaded at a twin berth jetty sited approximately 200m offshore
in about 17m of water. The jetty will be constructed on tubular piles. Tankers with capacity ranging from
10,000 to 80,000 dwt are expected to berth at the jetty typically twice per
week initially, rising to three to four times per week over the life of the
facility. Aviation fuel will run to shore through submarine pipes protected by
sand fill and rock armour which would not protrude above the existing seabed.
3.7
Defensive
fenders will be provided on the shore side of the jetty to protect against
possible collision from small craft straying into the area. Coupling points on the vessels would be
provided with slop trays to catch minor spills of aviation fuel during coupling
and de-coupling.
3.8
Aviation
fuel will be delivered to the airport site by means of buried 500mm diameter
twin sub-sea pipelines which will connect to the existing facility at Sha
Chau. The length of the twin
subsea pipelines will be about 4.8km. The pipelines will be installed in a dredged trench
and protected with sandfill and rock armour not protruding above the existing
seabed.
4. Key
Issues
4.1
There are
a number of important environmental issues associated with the project. These have all been thoroughly
addressed in this EIA and those that require special mitigation measures and
controls are highlighted below.
4.2
The
proposed pipeline requires dredging and other marine works, a very small
portion of which will be within the marine park. Sediment released to the water column could have an adverse
impact on the natural marine ecology, fisheries and other users of the sea
including leisure and industrial activities. Ecological receivers of particular concern include fish,
dolphins and sensitive flora such as corals.
4.3
Some
aspects of the marine construction works, most notably percussive piling work
for the jetty, may affect marine mammals which are known to be sensitive to
such noise.
4.4
The
proposed pipeline crosses a seabed which may have a rich maritime history. Care is required to avoid works
encroachment on any hitherto unidentified historical relics of cultural
heritage value.
4.5
It has
been identified in this EIA that routine operations at the facility will not
pose particular concern. With
careful design and management, no significant adverse impacts are expected. Nevertheless, handling bulk quantities
of aviation fuel presents concerns associated with any accident or incident
which could have an impact including that on human life. Hazard to life and the possible impact
of aviation fuel spills on the marine environment were therefore identified as
some of the most important issues considered in this EIA.
5. Approach
to Assessment
5.1
The study
scope and assessment requirements were defined in detail in the study brief
issued by EPD under the Environmental Impact Assessment Ordinance. In addition, the assessment has
followed the guidelines issued by EPD within the EIAO Technical Memorandum.
5.2
The
assessment approach was based on the following process:
¨
scoping
key environmental media that could potentially be affected by the project;
¨
identifying
regulatory requirements
¨
characterising
the existing environment;
¨
identifying
sensitive receivers and key environmental issues;
¨
assessment
of the likely extent of adverse impacts;
¨
identification
of mitigation and monitoring measures; and
¨
conclusions
on acceptability of any residual impacts.
5.3
Assessments
of the extent of adverse impacts of particular concern have been addressed
quantitatively as far as practicable.
These calculations have been undertaken by means of mathematical modelling
for air quality, odour, water quality, oil spill dispersion and fire heat flux,
using methodologies agreed with EPD.
6. EIA Findings
6.1
With the
implementation of standard good working site practices to control dust
emissions, no adverse impacts on air quality are expected during
construction. There will be low
level fugitive emissions of aviation fuel vapours during operations.
Concentrations of vapour reaching open air will be low and projections show
that they will be unlikely to impact on air quality. Odours from aviation fuel
vapours would be barely detectable at the site boundary and would not
significantly affect the surrounding environment.
6.2
There are
no airborne noise sensitive receivers in the vicinity of the site which is in a
heavy industrial setting and thus airborne noise is not identified as a key
issue for this project.
Nevertheless, good practice mitigation measures have been recommended to
keep noise levels to a practical minimum.
Water
Quality, Marine Ecology and Fisheries
6.3
The
project will involve dredging, pipelaying and backfilling in open waters. The dredged sediment is not expected to
be contaminated and thus leaching of potentially toxic substances is not an
issue. Similarly dredging would not result in appreciable nutrient enrichment
of marine waters. Sediment plume
modelling demonstrates that sediment released to the water column is likely to
settle rapidly and is unlikely to affect compliance with the statutory Water
Quality Objectives for key water quality parameters such as suspended sediment
and dissolved oxygen. With the
implementation of a range of recommended mitigation measures no sensitive flora
and fauna are expected to be impacted as of result of disturbances to water
quality or deposition of suspended sediment.
6.4
Site
works will be controlled to prevent erosive losses during ground works and
discharge of polluted effluents such that no adverse impact of water quality
would be expected.
6.5
Construction
of the pipeline would result in temporary loss of seabed habitat. However this is essentially
insignificant within the context of the large amount of adjacent heterogeneous
benthic habitat. Recolonisation is
expected to be reasonably rapid thereby returning the habitat and prey items
important for fish. Fish of the
type found in the study area are tolerant to temporary elevations of suspended
sediment concentrations and overall it is considered that the impact of the
project on fisheries resources is likely to be insignificant.
6.6
The study
area is frequented by marine mammals, particularly the Chinese White
Dolphin. This species is very
mobile and would be likely to avoid areas subjected to general water quality
and marine traffic disturbance during activities such as dredging and
pipelaying. The project necessitates percussive piling during construction of
the jetty. This could generate
intense noise which, if unmitigated, could potentially harm dolphins
approaching within 500m of the percussive piling.
6.7
For this
reason, a comprehensive set of mitigation measures have been identified to keep
noise to levels that would not
harm dolphins. These levels are
specified within this EIA.
Mitigation measures identified for the purpose of achieving these levels
include use of a jacket around the pile through the entire depth of the water
column and a noise attenuating bubble curtain within the jacket. The percussive
piling system itself will be designed and operated so as to minimise
disturbance and will be acoustically decoupled from the piling barge, as far as
this is practicable. Piling will
not be permitted during the peak calving season to protect young calves which
may be particularly vulnerable. A
dolphin exclusion zone will be established within a 500m radius of the piling
works. This zone will be monitored during piling by a trained observer. Piling will only proceed when the area
is clear of dolphins.
6.8
Additionally,
spot acoustic monitoring will be undertaken to identify submerged dolphins and
verify the efficacy of the surface surveillance work. Piling intensity will be gradually ramped up over a period
of 2–3 minutes of initially light hammer taps of increasing intensity and
piling events will be scheduled for specific daily time windows. These measures will alert dolphins to
the commencement of piling activities and allow them to safely vacate the area
before the full hammer force is used. With these measures in place it is
considered that although the dolphins would experience some nuisance and may
temporarily vacate the works site no harmful impacts on dolphins health are
expected.
6.9
In
addition to these measures during piling, an exclusion zone will be implemented
during dredging activities in the Marine Park and pre and post construction
phase dolphin abundance monitoring will be undertaken.
6.10
Routine
operations at the site would not result in discharge of polluting
effluents. The potential for minor
losses and spills will be mitigated through design of plant and provision of
containment facilities such that no residual impacts on water quality or biota
are expected.
6.11
The
likelihood of a large oil spill as a result of events such as tanker collision
or grounding, failure of supply pipeline or jetty based equipment is quantified
as being very low and within acceptable bounds. Nevertheless the consequences of such an event, however
unlikely, are potentially severe.
These have therefore been evaluated by means of mathematical
hydrodynamic and water quality models to assess the likely spread of a series
of credible worst case spill incidents.
6.12
Aviation
fuel is relatively volatile and subject to decay through a number of natural
processes including evaporation, emulsification, sedimentation and
biodegradation. The modelling
studies indicate that slicks, from events including grounding of the largest
tankers expected to use the facility, would dissipate before reaching any
sensitive receivers of concern such as beaches, vulnerable habitat or other
sites of ecological concern.
Nevertheless, comprehensive contingency plans will be drawn up to
specify the method by which to contain and remediate any spilled oil and
provide quick and effective response in the event of an emergency.
6.13
A
consequential risk analysis has been carried out to assess quantitatively
societal risks and individual risks to life associated with predicted worst
case events at the tank farm, jetty and
marine approach and in case of rupture of the submarine pipeline. The risk from hazards at the tank farm,
including catastrophic tank failure and fire, are calculated to lie within the
recognised acceptable range as defined in the EIAO Technical Memorandum
(EIAO-TM). Risks from the submarine pipeline are extremely low mainly because
the risk of rupture is extremely low and because emulsification would occur as
aviation fuel surfaces. The latter
would render ignition extremely difficult.
6.14
Hazards
such as groundings and strikings at the jetty or involving approaching aviation
fuel tankers have also been examined. Aviation fuel on the sea surface would
have a relatively high flashpoint and probably be difficult to ignite. Nevertheless worst case modelling,
assuming surface fires, has been undertaken. The maximum individual risk is
also deemed to be acceptable using EIAO Technical Memorandum criteria. Further,
the societal risk lies in the acceptable region of Annex 4 of the EIAO –
TM. Neverthless, the design
of the facility will meet best practice and, as such, a number of operational
measures will be incorporated.
Landscape,
Visual and Cultural Heritage
6.15
The
project site is located in a heavily industrialised neighbourhood and the
proposed facility is thus compatible with adjacent land uses. There would be
some minor impacts within this local context during the early phases of
construction. This would subsequently be compensated such that the net result
may even be considered beneficial. A number of mitigation measures are
identified to facilitate sympathetic design and landscaping.
6.16
The high
quality landscape of the natural setting of Castle Peak behind the site would
remain unaffected. The development
will not significantly impact on the local landscape or important view
sightlines. However, a
comprehensive range of planting proposals including the use of the 1.5m
perimeter landscaped bund and a 4m landscaped mound in future tank expansion
areas will ensure that the tanks are screened from key visual receivers.
6.17
There are
no declared monuments in or close to the site and there will be no impacts on
any aspect of terrestrial cultural heritage. The archaeological status of the proposed pipeline routing
is not known. The rich maritime
history of the general study area suggests a high archaeological
potential. It is therefore recommended
that the exact pipeline route, which is still subject to detailed design within
the broadly identified route corridor, should be investigated by a qualified
marine archaeologist prior to commencement of construction works, to confirm
the absence of shipwrecks or other seabed historical artefacts. This should comprise a geophysical survey
supplemented by a dive survey, if necessary, to investigate any anomalous
findings.
6.18
Waste
management issues have been assessed in line with the principles of the waste
management hierarchy promoted by EPD.
In order of priority these involve :
¨
Avoidance;
¨
Minimisation;
¨
Reuse and
Recycling;
¨
Treatment;
and
¨
Disposal.
6.19
Numerous
recommendations on good practice and mitigation measures have been recommended
to put these principles into effect.
6.20
The
largest waste stream by volume will be dredged mud which will be disposed of
offshore at a disposal site administered by the Civil Engineering
Department. Review of
available sediment quality data gives reason to believe that the sediments are
not contaminated. Nevertheless, the sediments will be fully characterised in
line requirements of the Dumping at Sea Ordinance and EPD’s Sediment Quality
Assessment Framework in due course in support of applications for any necessary
Dumping Permits.
6.21
Construction
and demolition waste arising from excavation and site formation works will be
re-used on site to form a landscape mound for planting. Other waste streams are relatively low
in volume. Types and quantities of all residual wastes expected to arise during
construction and operation have been identified, quantified and suitable
disposal sites identified.
6.22
Measures
have been identified to ensure safe handling of chemicals used on site and to
minimise arisings of chemical waste.
Similarly measures are recommended to ensure safe handling and disposal
of all chemical wastes.
6.23
Measures
for safe disposal of sewage and other effluents including storm drainage in
both the construction and operational phases are recommended.
7. Mitigation
and Monitoring
7.1
The EIA
process has facilitated integration of environmental considerations into the
fundamental design process for the project. The principal mitigation measures identified are those
achieved through siting and plant design.
In addition, a number of specific construction and operational phase
measures have been identified to minimise potential adverse environmental
impacts. The most notable of these have been discussed above. A complete listing of all
recommendations and in-built mitigation measures are detailed in the form of an
Implementation Schedule. These measures will be implemented by AA (the project
proponent) through its Franchisee, and enforced by EPD by means of the
regulatory empowerment of the Environmental Impact Assessment Ordinance.
7.2 A monitoring and audit programme will be implemented by the proponent to confirm that all recommended mitigation measures have been implemented or amended, if subsequently found necessary. A design audit is recommended to identify measures which are to be integrated into the design. These items will include:
¨
land/marine
spill response plan;
¨
pipeline
leak detection and automatic shut-down system;
¨
pipeline
rock armour protection;
¨
tank
high level shut-down;
¨
tank
bunding;
¨
tank
leak drainage isolation and containment system;
¨
on-site
fire fighting equipment;
¨
jetty
protection;
¨
aviation
fuel delivery shut-down valves;
¨
dolphin
acoustic monitoring;
¨
dolphin
exclusion zones;
¨
dolphin
abundance monitoring;
¨
underwater
noise monitoring during piling;
¨
piling
acoustic decoupling methods;
¨
bubble
jacket design; and
¨
landscape
design drawings.
7.3
During
the construction phase, ambient water quality will be monitored when marine
construction works are taking place within 1000m of the Lung Kwu Chau and Sha
Chau Marine Park. Measurements of
suspended solids, turbidity and dissolved oxygen shall be taken on a routine
basis to enable any deteriorating water quality to be readily detected and
timely action to be taken to rectify the situation.
7.4
Regular
site audits will be carried out to confirm that good working practice is
adhered to at all times and the mitigation measures identified in the
Implementation Schedule are being followed.
8. Overall
Conclusions
8.1
The
proposed Permanent Aviation Fuel Facility site at Tuen Mun Area 38 and route
for the connecting pipeline to tie in with the existing twin subsea pipelines
from Sha Chau to HKIA represents the best available environmental option which
meets the fundamental requirements of the facility.
8.2
Implementation
of a comprehensive list of mitigation measures as specified in the Implementation
Schedule is recommended along with the environmental management regime detailed
in the Environmental Monitoring and Audit Manual.
8.3
With the
adoption of these mitigation measures, the project will not result in any
unacceptable residual environmental impacts. The project will fully comply with all environmental
regulations and standards prevailing in Hong Kong.