11.1
With the
construction and operation of the proposed concrete batching plant, air quality,
noise nuisance, water quality and visual impact induced by the barges
transportation can be minimized. All sensitive receivers around the Cyberport
and along the marine transport route would benefit from the reduction.
11.2
In order to
further reduce the environmental impact, apart from the requirements stipulated
in Best Practicable Means Requirement for Cement Works (Concrete Batching
Plant) and Air Pollution Control (Construction Dust) Regulation, the concrete
batching plant will incorporate the following design and practices:
·
Dust collectors
will be sized to exceed the requirement of the Specified Processes Regulation.
·
For Stage 1, the
cement tankers will be working inside enclosure with cladding to reduce noise.
·
For stage 2,
Cement will be transferred directly from barges to the plant. There is no need
for cement tankers for intermediate transfer.
·
All mixing will be
in the enclosed electric motor driven plant mixer, NOT in trucks.
·
Truck loaded with
concrete will be in wet form.
·
All washing water
used by the plant and stormwater will be collected and stored within the plant
and recycled for re-use in the plant.
·
No water will be
discharged outside the plant boundary.
·
Concrete recycling
machine used to recycle waste material to slurry water and aggregates for
reuse.
11.3
While the
Cyberport can continue to be constructed using concrete delivered by barges to
the site from an off-site concrete batching plant, there are obviously overall
environmental benefits of setting up an on-site concrete batching plant. The
additional environmental benefits with the concrete batching plant on site and
the key environmental problems avoided will include:
·
The number of
barges for delivery can be much reduced. These will reduce the noise, air
quality and water quality and marine traffic impact.
·
Any mitigation
measures can be easily incorporated into the stationary concrete batching plant
on site. However, it is difficult to apply on the moving barges.
·
It is much easier
to control the delivery time. This will avoid concreting in the restricted
hours caused, otherwise, by the delay of barges.
·
With an existing
earth mound and future commercial buildings in between the sensitive receivers
and the proposed plant location, the visual impact of the concrete batching
plant can be much reduced. However, this cannot be done on the large number of
barges.
11.4
A summary of the
key findings is given in Table 11.1. Based on this, it can be concluded that
the construction of the proposed on-site concrete batching plant is unlikely to
cause adverse impacts on air quality, noise, water quality and visual at
Telegraph Bay. Besides, the on-site concrete batching plant can further reduce
the environmental and traffic nuisances caused by the barges. From the
environmental point of view, the on-site concrete batching plant will have
significant benefits to the local sensitive receivers.
Table 11.1 Summary of Environmental Impact
Assessment Findings
|
Environmental Aspect |
Key Impacts (without mitigation measures) |
Proposed Mitigation Measures |
Residual Impacts (after mitigation) |
|
Construction Phase |
|||
|
Air Quality |
Short term elevated dust levels |
Watering of road surfaces at every 2 hours, on-site vehicle
speed control, covering/dampening of stockpiles in dry/windy conditions |
Acceptable |
|
Noise |
Short-term elevated construction noise levels |
Adoption of quiet powered mechanical equipment; use of acoustic
barrier, use of semi-enclosure |
Acceptable |
|
Water Quality |
Limited discharge of sediment-laden wastewater |
Site management. Treatment of effluent prior to discharge. |
Acceptable |
|
Wastes |
Limited spoil and construction wastes |
Site management, segregation of waste, and waste minimisation |
Acceptable |
|
Landscape & Visual |
Change in visual character |
Use of earth mound to screen the powered mechanical equipment |
Acceptable |
|
Operation Phase |
|||
|
Air Quality |
Limited dust emissions |
Implementation of Best Practical Means for concrete batching
plant |
Acceptable |
|
Noise |
Limited noise emissions |
Use of quieter powered mechanical plant and full enclosure for
the noisy component of the plant; all concrete mixing done inside plant |
Acceptable |
|
Water Quality |
Discharge of wash water |
Use of treatment plant to treat and recycle all wash water; no
water will be discharged from the plant |
Acceptable |
|
Waste |
Limited concrete and aggregate wastes |
Use of concrete recycling machine to recycle waste material for
reuse |
Acceptable |
|
Visual Impact |
Change in visual Character |
Use of earth mound in the short-term and the use of newly
completed buildings afterwards to screen the plant |
Acceptable |
11.5 It has been estimated that about eleven tower blocks with an estimated population of 1,300 at Lower Baguio Villas and six buildings with an estimated population of 300 along Sassoon Road would be protected by the above mitigation measures.