3.1
Key findings of the assessment of potential environmental impacts associated
with the construction and operation phases of the proposed Project are
summarized below.
3.2
Construction noise impacts would be low due to the limited scale of
construction works and the NSRs are located far away from the works area. Implementation of good construction site
practices was recommended to minimize construction noise disturbance.
3.3
Potential helicopter noise impact from the Project is the key issue of
this EIA study. A detailed helicopter
noise impact assessment was carried out, covering coastal
areas within 300m of the project boundary and flight paths in the western
district. The assessment included existing helipad
operation alone and new helipad operation alone, as well as
cumulative impacts from the existing and
new helipads, based on conservative predictive modelling assumptions and worst
case scenarios.
3.4
The study area of the present MFT site is in an urban environment with
high noise background predominantly due to surrounding road traffic (noise
levels up to Leq (4 hour) 73 dB(A)), as well as occasional helicopter noise
from the current helipad operation (noise levels approximately Leq (4 hour) 65
- 69 dB(A)). It should be noted that
the existing MFT Helipad is an Exempted Designated Project and not governed by
the EIAO. For the purpose of this EIA
Study in accordance with the EIAO requirements, in
addition to the Lmax 85 dB(A) daytime (0700–1900) noise assessment criterion, evening time (1900-2300)
noise assessment criteria of Leq (4 hours) 65
dB(A) as well as Lmax 85 dB(A) were
also proposed for the assessment of the helicopter noise impacts
from the proposed new helipad.
3.5
All direct measures to mitigate potential noise impacts from the
operation of the Project were exhausted during the EIA study, taking into
account the specific site conditions and constraints. The current Project proposal has incorporated the maximum
practicable mitigation measures which includes (1) helicopter type control -
not to use the larger S92 helicopter type which would have larger noise
emissions, and to adopt the existing helicopter type of S76C+ or other
helicopter types with lower noise emission; and (2) flight frequency
arrangement control. This would ensure
that (1) the helicopter noise impacts arising from new helipad alone would
comply with the proposed stringent noise criteria; and (2) the cumulative noise
levels from the existing and new helipads at the representative NSRs would not
be worse than the existing allowable helipad operation conditions by 1.0 dB(A). Therefore the residual impact from the
Project is considered to be not significant and acceptable.
3.6
To ensure that the proposed new
helicopter flight frequency is acceptable in terms of noise impact
to the NSRs, any
future increase in helicopter movements would be incremental
and its noise impact would be closely monitored.
3.7
Dust nuisance during the construction phase would be expected to be
insignificant with the implementation of dust suppression measures stipulated
in Air Pollution Control (Construction Dust) Regulation. During operation of the Project, emissions
from proposed helipad to the surrounding environment would be limited.
3.8
The construction phase water quality impact would be temporary and
localised. No adverse residual water
quality impacts would be expected from the Project with proper implementation
of the recommended mitigation measures.
3.9
Wastes generated by the construction activities would include general
refuse from the workforce and chemical waste from any maintenance of
construction plant. Good site practices
for handling, transporting and disposed of these waste arisings would be
implemented.
3.10
Environmental monitoring was recommended for helicopter noise during the
operation of the Project.
Construction site audit was also recommended to check the implementation
of the noise, dust, water quality and waste management mitigation measures during
the construction phase. Details of the
programme are presented in a separate Environmental Monitoring and Audit
Manual.