No adverse air quality impact is
anticipated during the construction phase with the implementation of good site
practices and appropriate mitigation measures. The EIA Report has identified that
construction dust is the only concern as the construction scale is relatively
small, and dust emission from the site could be audited during the regular site
inspection.
In order to ensure no adverse air quality
impact will arise from the construction of the Project, it is necessary to
undertake regular environmental audits and site inspections to ensure those
recommended mitigation measures were properly implemented. The requirements of the environmental
audit programme were set out in Section 8
of the Manual.
The audit programme will verify the
implementation status and evaluate the effectiveness and stability of the
mitigation measures.
The EIA Report has recommended dust
control and mitigation measures.
The Contractor should be responsible for the design and implementation
of these measures.
The dust control measures stipulated in
the Air Pollution Control (Construction
Dust) Regulation should be incorporated in the contract specifications. These should be implemented during
construction in order to reduce dust impact produced by the site activities. Typical control measures are:
• skip hoist for material transport should be
totally enclosed by impervious sheeting;
• every vehicle should be washed to remove any dusty
materials from its body and wheels before leaving the construction site;
• the area where vehicle washing takes place and the
section of the road between the washing facilities and the exit point should be
paved with concrete, bituminous materials or hardcores;
• where a site boundary adjoins a road, streets or
other accesses to the public, hoarding of not less than 2.4 m high from ground
level should be provided along the entire length except for a site entrance or
exit;
• every stock of more than 20 bags of cement should
be covered entirely by impervious sheeting placed it an area sheltered on the
top and the 3 sides;
• all dusty materials should be sprayed with water
prior to any loading, unloading or transfer operation so as to maintain the
dusty materials wet;
• all stockpiles of aggregate or spoil should be
covered and water applied;
• the height from which excavated materials are
dropped should be controlled to a minimum practical height to limit fugitive
dust generation from unloading; and
• the load of dusty materials carried by vehicle
leaving a construction site should be covered entirely by clean impervious
sheeting to ensure dust materials do not leak from the vehicle.
The air quality mitigation measures
recommended in the EIA Study are outlined in the Environmental Mitigation
Implementation Schedule (EMIS) (Annex B).
In the event of complaints, or
non-compliance / area of improvement is observed, the ET and the Contractor
should be responsible for reviewing the effectiveness of these mitigation
measures and for proposing to ER for approval, designing and implementing
alternative or additional mitigation measures as appropriate.