This Section presents a summary of the key potential environmental outcomes associated with the construction and operation of the Project.
Unmitigated construction activities associated with the Project will not cause adverse noise impact to the nearby NSRs as the predicted construction noise levels are in the range of 46 – 61 dB(A), which comply with the stipulated noise criterion. The mitigation measure of adopting good site practice is proposed to further minimise the construction noise impact to the environment. Regular site audits will be conducted during construction to ensure the plant inventory used on site is consistent with the assumptions in the EIA report.
With the adoption of a maximum sound power level of 100 dB(A) and a pure tone free wind turbine , the predicted facade noise levels will comply with the night-time noise criterion at all NSRs. It is proposed that the allowable maximum sound power level shall be included in the tender specification of wind turbine. Noise monitoring during the operational phase is recommended so as to ensure the compliance with the stipulated noise criterion at the nearby NSRs. To ensure the operational noise level complies with the noise standard, the supplier shall guarantee the wind turbine with allowable maximum noise level of 100 dB(A) and pure tone free, by providing certificate of measurement and verify the overall noise level during commissioning and testing in accordance with international standard procedures such as IEC 61400-11.
The ecological resources recorded within the Study Area included secondary woodland, shrubland, shrubby grassland, stream and village/ developed areas, as well as associated wildlife. Of these habitats, secondary woodland and the middle course of a stream near to Lo Tik Wan (Stream S4) have moderate to high and high ecological value respectively. The remaining habitats are of low or low to moderate ecological value. A total of 14 species of conservation interest were recorded within the Study Area, including five bird species (Black Kite, Greater Coucal, Lesser Coucal, Emerald Dove and White-bellied Sea Eagle), eight uncommon butterfly species (Red Lacewing, Bush Hopper, Common Duffer, White-edged Blue Baron, Tree Flitter, Yellow Orange Tip, Swallowtail and Small Cabbage White) and one amphibian (Romer’s Tree Frog). Three calling male Romer’s Tree Frog were recorded within and adjacent to the Project Area during the surveys. A total of 17 bird species were observed during the vantage point surveys, with a total of 1,290 flight attempts in the Study Area. The flight attempts of most of the recorded species were generally flying < 10 m above the ground level near the Project Area. Only Black Kite (144 attempts, the maximum number of individuals recorded was 23 during the surveys), Barn Swallow (3 attempts) and Little Swift (2 attempts) were recorded flying over and crossing the location of the proposed wind turbine at a height > 10 m and <100 m above the ground level during the surveys.
In conclusion, the direct ecological impact due to the construction of the wind turbine is expected to be low, and will not contribute to any potential cumulative impact. In view of the generally poor vegetation cover and the dryness of the upland areas, it is believed that the Project Area and areas in the vicinity do not provide optimal habitats for the Romer’s Tree Frog. The impacts on the Romer’s Tree Frog are expected to be low given that pre-construction translocation of Romer’s Tree Frogs (adult and tadpoles, if any) present at the site will be conducted.
Bird collisions are the
main concern of the operational impacts of any wind turbine development. Barn Swallow,
Little Swift and Black Kite, recorded as utilising the Project Area in this
study, are the confirmed potential
species that may be affected by the wind turbine during operation. Site selection is crucial
to minimizing wind turbine bird collision. Since the wind turbine site is not
considered to be either within important bird habitat or on the flight path of
migratory birds, the impacts due to bird collision are of low magnitude and
therefore not considered to be unacceptable.
No adverse residual impact is expected after the implementation of
the recommended mitigation measures.
One year bird monitoring
will be undertaken to demonstrate that the wind turbine is having low magnitude
of and not having an unacceptable impact on bird species.
The whole Study
Area is considered to be covered under one single Landscape Character Area, LCA
1 - North Lamma Coastal Uplands. Landscape Resources found within the Study Area include LR1 - secondary woodland, LR2 - shrubland, LR3 - shrubby grassland, LR4 - streams and
LR5 -village/developed area.
The following table gives the
quantification, disturbance and net loss of these LCA and LRs.
Table 10.1 Summary of Net Loss to LCA1 and Various Landscape Resources
|
LCA/LR |
Type of Landscape
Resources Present in the LCA/LR |
Quantification of
Landscape Resources within the LCA/LR |
Area in conflict with
the proposed works |
Net Loss in Area |
|
LCA1 |
North Lamma Coastal Uplands |
Approx. 79.4 ha |
Approx. 3,100 m2 |
Approx. 1,700 m2 |
|
LR1 |
Secondary
Woodland |
20.5 ha |
0m2 |
0m2 |
|
LR2 |
Shrubland |
49.4 ha |
0m2 |
0m2 |
|
LR3 |
Shrubby
Grassland |
5.7 ha |
Approx. 3,100 m2 |
Approx. 1,700 m2 |
|
LR4 |
Stream |
Total 1.1 km |
0 km |
0 km |
|
LR5 |
Village/Developed
Area |
3.8 ha |
0m2 |
0m2 |
Specific mitigation measures have been proposed to minimize
identified impacts, including MM1 - reinstatement of disturbed areas (approx. 1,400 sq.m.), MM2- compensatory planting (approx. 1,400 sq.m.) and MM4 - soil conservation.
The extent
and location these mitigation measures are shown on Figure 6.24. All proposed MMs would be managed and
maintained by the project proponent.
With the implementation of the mitigation measures proposed, the magnitude of change to LCA1 and LR3 are small. The residual impact significance threshold of LCA1 is moderate/ adverse for both years 1 & 10. Appropriate landscape planting including trees, shrubs and grasses will result in a net increase in the quantity of vegetation at the Project Site resulting in a significance threshold of the residual impact for LR3 to “slight/adverse” during Year 1 of operation and “slight/beneficial” during Year 10 of operation.
Visually,
the proposed wind turbine can be seen from some parts of Lamma Island and
Hong Kong Island South and a total of 16 VSRs are identified. These VSRs are
classified into 3 main groups:
·
Resident and people at work VSRs on Lamma Islands
where the proposed wind turbine would be visible
·
Resident and people at work VSRs on Hong Kong
Island south and Ap Lei Chau
·
Visitors and viewers
in transit such as those on hiking tracks on Lamma Island and along the ferry
routes as well as those in Ocean
Park
·
Visitors to the Tai Ling Pavilion and cable road
adjacent to the Project Site
Specific mitigation measures have been proposed to minimize
the visual impacts. These include MM1 - reinstatement of disturbed areas (approx. 1,400 sq.m.), MM2- compensatory planting (approx. 1,400 sq.m.),
MM3 - colour
scheme and MM5 - selection of low rotating speed machine. The extent and location these
mitigation measures are shown on Figure 6.24. All proposed MMs
would be managed and maintained by the project proponent.
With mitigation
measures, the proposed wind turbine would result in slight
to moderate/ adverse residual visual impact on views from the
first 3 groups of viewers during operation.
At Tai Ling Pavilion and the cable route adjacent to the site, the visual significant threshold would be significant as the wind turbine and built structures would be dominating. However, whether it is an adverse or beneficial impact would very much depend on the viewers acceptance towards the use of this kind of renewable energy as a substitute to coal burning.
One of the objectives of this project is to educate the public and in particular students, for promotion of green awareness. With the gain in knowledge of the benefits of renewable energy such as the improvement of air quality, the likelihood of acceptance of the visual impact would be increased.
The overall residual impacts on landscape and visual aspects are considered to be acceptable with mitigation measures.
Dust
nuisance is the only potential air quality impacts during the construction of
the Project. Site formation,
foundation construction, cable laying, wind turbine erection and landscaping
works are the main construction activities. Wind erosion, materials handling, on-site stockpiling and vehicles
movements are the major dusty activities.
Since the site area is small, construction period is short with minimal
construction activities and the distance from the ASRs is more than 185 m away,
therefore, with the implementation of dust suppression measures, the potential
for causing dust impact is very low.
However, to protect the ASRs, regular site auditing is recommended to
ensure the recommended mitigation measures are properly
implemented.
No air quality impact would be envisaged during
the operation of the wind turbine.
The wind turbine will displace emissions of greenhouse gases and other
emissions from conventional power generating plant. Estimates of the potential emission reductions have been
presented.
The EIA has dealt with the assessment of impacts on water quality from the construction and operation of the wind turbine on Lamma Island.
During the construction phase it was determined that minor impacts to water quality could arise directly from land-based construction works. These works relate to excavation and construction of the foundation for the wind turbine, and underground cable laying. No direct construction runoff is expected. However, stormwater runoff from the construction site could occur during rainstorms. Mitigation measures were described, which would provide a series of good site management options to minimise the impact of stormwater runoff.
No operational impacts to water quality are expected to occur. No mitigation measures are therefore necessary. Based on the impact assessment, no EM&A measures are required. The mitigation measures specified as well as good site management skills are considered sufficient to prevent impacts occurring.
The construction works will involve some site formation which will necessitate the removal of small quantities of spoil. The quantity of waste materials arising from the construction phase (approximately 1,300 m3 of excavated materials) is not expected to be high as most of the spoil (95% of the excavated materials) will be used as backfill, but practical measures will be taken to avoid, minimise and recycle wastes. The remaining portion will be transported by trucks to the HEC Power Station for offsite disposal. Good construction practices, including limiting activities within the site boundary and avoiding of filling and illegal dumping by site management and audit, are recommended to ensure that adverse environmental impacts are prevented.
During construction of the Project, environmental monitoring will be necessary to assess the effectiveness of measures implemented to mitigate potential noise and ecological impacts. Regular environmental auditing is also recommended to ensure that potential impacts from other sources are adequately addressed through the implementation of the mitigation measures defined in this EIA Report.
During operation of the Project, the monitoring work is focussed on ecology, specifically operation phase impacts to birds and to a noise sensitive receiver. Details are presented in the EM&A Manual.
No unacceptable residual impacts are predicted for the construction and operation of the Project. This section presents the environmental outcome of the Project.
The wind turbine will be built in a grid connection scheme for supplying “green” electricity to HEC customers. The project will have the following environmental benefits:
· Demonstration of utilizing wind energy for power generation: The proposed wind turbine will be the first utility scale and grid-connected wind project in Hong Kong. Based on the wind potential on Lamma, the proposed wind turbine will harvest about 700 MWh of electricity per annum, helping to avoid the use of up to 240 tonnes of coal and reduce the associated emissions every year.
· Education purpose: Visitors’ facilities such as display boards and guided tour will be provided at the wind turbine site to explain the principle of power generation by wind and the benefits of renewable energy. The wind turbine project will serve as educational use for promotion of green awareness among the public, in particular with students.
· Wider application of renewable energy: The project will provide invaluable local experience on the design, construction, operation and maintenance of wind turbines. Future utilization of wind energy in Hong Kong can be explored based on the information collected and experience gained, keeping pace with Government's policy, and the publics expectation of the promotion of renewable energy and improvement in air quality.
The wind turbine has been based on an environmentally friendly design which is beneficial to the environment as it helps to reduce air pollutant emissions and greenhouse gas emissions. Environmental impacts have been largely avoided through a detailed and careful site selection exercise for the wind turbine.
Desktop screening and site surveys conducted to identify potential sites for a wind turbine of suitable size on Lamma and Po Toi Island based on the criteria recommended in the guidelines for wind energy development issued by reputable international organizations of wind energy. The site search was confined to Lamma and Po Toi where reliable wind data are available.
Po Toi Island is an ecologically sensitive area which has been identified as a potential Country Park and is a known location of the endemic Romer’s Tree Frog. As there is no vehicular access for sites of favourable wind potential on Po Toi the majority of the wind turbine equipment/materials would have to be delivered to site by helicopters. Construction of a new access road was not considered suitable due to the potential for adverse environmental impacts. Considering the limited payload of local helicopter services, the maximum capacity of a wind turbine on Po Toi would be restricted to about 50 kW. Any electricity generated on Po Toi would also be connected to the HEC grid. This could only be done through the use of submarine cables. Given that the marine waters between Po Toi, Hong Kong and Lamma Island are already quite congested with seabed utilities, finding an acceptable route for a cable may prove technically challenging. Although not expected to be unacceptable, the installation of a submarine cable would introduce additional environmental impacts.
In view of the accessibility considerations and absence of a power grid, Po Toi is considered neither technically feasible nor environmentally and economically attractive for a demonstration project with commercial scale wind turbine.
Once the above considerations had been accounted for, site selection was focussed on Lamma Island. The wind turbine site was then examined against engineering requirements and environmental concerns and further refined using the following site screening criteria:
· Wind potential;
· Site access;
· Height restriction;
· Electrical connection; and
· Area and land-use
Taking into account the above criteria, wind
turbine location was identified with the application of
constraint mapping techniques. The site is situated away
from the ecological sensitive areas, including SSSI and the potential Country
Park at South Lamma, and along the existing 275 kV Cable Routes which are the only
vehicular roads on Lamma island.
The EIA has critically assessed the overall acceptability of any environmental impacts likely to arise as a result of the construction and operation of the wind turbine on Lamma Island. Where necessary and practicable, the EIA has specified the conditions and requirements for the detailed design, construction and operation of the Project in order to mitigate environmental impacts to acceptable levels.
This EIA Study has predicted that the Project will comply with all environmental standards and legislation after the mitigation measures are implemented. The EIA has thus demonstrated the acceptability of any residual impacts from the Project and the protection of the population and environmentally sensitive resources. Where appropriate, EM&A mechanisms have been recommended before and during construction to verify the accuracy of the EIA predictions and the effectiveness of recommended mitigation measures. A post project monitoring exercise has been recommended to verify overall project performance.
The study concluded that there would be no adverse long term or cumulative effects/impacts on the environment.
In conclusion, it is considered that the EIA provides a suitable basis for the Director of Environmental Protection to consider granting the Environmental Permit to allow the construction and operation of the Project.
