Air Quality Impact (Construction)

3.6.1.1 2.1 General Dust Control Measures The following dust suppression measures should be implemented:

Frequent water spraying for active construction areas (4 times per day for active areas in Po Kak Tsai and 8 times per day for all other active areas), including areas with heavy construction and slope cutting activities
80% of stockpile areas should be covered by impervious sheets
Speed of trucks within the site should be controlled to about 10 km/hr
All haul roads within the site should be paved to avoid dust emission due to vehicular movement
To minimize Contractor Construction During EIA Recommendation
adverse dust Works Sites Construction and Air Pollution
emission generated Control (Construction
from various Dust) Regulation
construction
activities of the
works sites
3.6.1.2 2.1 Best Practice for Dust Control

The relevant best practices for dust control as stipulated in the Air Pollution Control (Construction Dust) Regulation should be adopted to further reduce the construction dust impacts of the Project. These best practices include:

Good site management

The Contractor should maintain high standard of housekeeping to prevent emission of fugitive dust.
Loading, unloading, handling and storage of raw materials, wastes or by-products should be carried out in a manner so as to minimize the release of visible dust emission.
Any piles of materials accumulated on or around the work areas should be cleaned up regularly.
Cleaning, repair and maintenance of all plant facilities within the work areas should be carried out in a manner minimizing generation of fugitive dust emissions.
The material should be handled properly to prevent fugitive dust emission before cleaning.

Disturbed Parts of the Roads

Each and every main temporary access should be paved with
concrete, bituminous hardcore materials or metal plates and kept clear of dusty materials; or
Unpaved parts of the road should be sprayed with water or a dust suppression chemical so as to keep the entire road surface wet.
To minimize Contractor Construction During EIA Recommendation
adverse dust Works Sites Construction and Air Pollution
emission generated Control (Construction
from various Dust) Regulation
construction
activities of the
works sites

Exposed Earth

Exposed earth should be properly treated by compaction, hydroseeding, vegetation planting or seating with latex, vinyl, bitumen within six months after the last construction activity on the site or part of the site where the exposed earth lies.

Loading, Unloading or Transfer of Dusty Materials

All dusty materials should be sprayed with water immediately prior to any loading or transfer operation so as to keep the dusty material wet.

Debris Handling

Any debris should be covered entirely by impervious sheeting or stored in a debris collection area sheltered on the top and the three sides.
Before debris is dumped into a chute, water should be sprayed so that it remains wet when it is dumped.

Transport of Dusty Materials

Vehicle used for transporting dusty materials/spoils should be covered with tarpaulin or similar material. The cover should extend over the edges of the sides and tailboards.

Wheel washing

Vehicle wheel washing facilities should be provided at each construction site exit. Immediately before leaving the construction site, every vehicle should be washed to remove any dusty materials from its body and wheels.

Use of vehicles

Immediately before leaving the construction site, every vehicle should be washed to remove any dusty materials from its body and wheels.
Where a vehicle leaving the construction site is carrying a load of dusty materials, the load should be covered entirely by clean impervious sheeting to ensure that the dusty materials do not leak from the vehicle.

Site hoarding

Where a site boundary adjoins a road, street, service lane or other area accessible to the public, hoarding of not less than 2.4m high from ground level should be provided along the entire length of that portion of the site boundary except for a site entrance or exit.

Blasting

The areas within 30m from the blasting area should be wetted with water prior to blasting.

Air Quality Impact (Operation)

3.5.2.2 2.2 The following odour containment and control measures will be provided for the proposed sewage treatment work at the BCP site:

The treatment work will be totally enclosed. Negative pressure ventilation will be provided within the enclosure to avoid any fugitive odorous emission from the treatment work.
Further odour containment will be achieved by covering or confining the sewage channels, sewage tanks, and equipment with potential odour emission.
Proper mixing will be provided at the equalization and sludge holding tanks to prevent sewage septicity.
Chemical or biological deodorisation facilities with a minimum odour removal efficiency of 90% will be provided to treat potential odorous emissions from the treatment plant including sewage channels / tanks, filter press and screening facilities so as to minimize any potential odour impact to the nearby ASRs.

To minimize DSD BCP Operation EIA recommendation potential odour Phase impact from operation of the proposed sewage treatment work at BCP The use of movable barrier for certain PME can further alleviate the construction noise impacts. In general, a 5 dB(A) reduction for movable PME and 10 dB(A) for stationary PME can be achieved depending on the actual design of the movable noise barrier. The Contractor shall be responsible for design of the movable noise barrier with due consideration given to the size of the PME and the requirement for intercepting the line of sight between the NSRs and PME. Barrier material with surface mass in excess of 7 kg/m2 is recommended to achieve the predicted screening effect.

Noise Impact (Construction)
4.4.1.4 3.1 Adoption of Quieter PME To minimize the Contractors Construction During EIA recommendation,
Use of the recommended quieter PME such as those given in the BS5228: Part 1:2009 and presented in Table 4.14, which can be found in Hong Kong. construction airborne noise impact Work Sites Construction EIAO and Noise Control Ordinance (NCO)
To minimize the Contractors Construction During EIA recommendation,
construction air- Work Sites Construction EIAO and NCO
borne noise impact

4.4.1.4 3.1 Use of Noise Enclosure/ Acoustic Shed To minimize the Contractors Construction During EIA recommendation, construction air-Work Sites Construction EIAO and NCO

The use of noise enclosure or acoustic shed is to cover stationary PME borne noise impact

such as air compressor and concrete pump. With the adoption of the noise enclosure, the PME could be completely screened, and noise reduction of 15 dB(A) can be achieved according to the GW-TM.

4.4.1.4 3.1 Use of Noise Insulating Fabric To minimize the Contractors Construction During EIA recommendation, construction air-Work Sites Construction EIAO and NCO

Noise insulating fabric can be adopted for certain PME (e.g. drill rig, borne noise impact

pilling auger etc). The insulating fabric should be lapped such that there are no openings or gaps on the joints. Technical data from manufacturers state that by using the Fabric, a noise reduction of over 10 dB(A) can be achieved on noise level.

The good site practices listed below should be followed during each phase of construction:

To minimize the Contractors Construction During EIA recommendation,
construction air- Work Sites Construction EIAO and NCO
borne noise impact
Noise Impact (Operation) Road Traffic Noise
Table 4.42 and Figure 4.20.1 to 4.20.4 3.2 Erection of noise barrier/ enclosure along the viaduct section. To minimize the road traffic noise along the connecting road of BCP Contractor Loi Tung and Fanling Highway Interchange Before Operation EIAO and NCO
Fixed Plant Noise
Table 4.46 3.2 Specification of the maximum allowable sound power levels of the proposed fixed plants during daytime and night-time. To minimize the fixed plant noise impact Managing Authority of the buildings / Contractor BCP, Administration Building and all ventilation buildings Before Operation EIA recommendation, EIAO and NCO

4.5.2.4 3.2 The following noise reduction measures shall be considered as far as practicable during operation:

To minimize the Managing BCP, Before EIAO and NCO
fixed plant noise Authority of Administration Operation
impact the buildings / Building and all
Contractor ventilation
buildings

Water Quality Impact (Construction)

5.6.1.1 4.1 Construction site runoff and drainage

The site practices outlined in ProPECC Note PN 1/94 should be followed as far as practicable in order to minimise surface runoff and the chance of erosion. The following measures are recommended to protect water quality and when properly implemented should be sufficient to adequately control site discharges so as to avoid water quality impacts:

At the start of site establishment, perimeter cut-off drains to direct off-site water around the site should be constructed with internal drainage works and erosion and sedimentation control facilities implemented. Channels (both temporary and permanent drainage pipes and culverts), earth bunds or sand bag barriers should be provided on site to direct stormwater to silt removal facilities. The design of the temporary on-site drainage system should be undertaken by the Contractor prior to the commencement of construction.
The dikes or embankments for flood protection should be implemented around the boundaries of earthwork areas.
To control site Contractor Construction Construction Practice Note for
runoff and Works Sites Phase Professional Persons
drainage; prevent on Construction Site
high sediment Drainage (ProPECC
loading from Note PN 1/94)
reaching the
nearby
watercourses

Temporary ditches should be provided to facilitate the runoff discharge into stormwater drainage system through a sediment/silt trap. The sediment/silt traps should be incorporated in the permanent drainage channels to enhance deposition rates, if practical.

Sand/silt removal facilities such as sand/silt traps and sediment basins should be provided to remove sand/silt particles from runoff to meet the requirements of the TM standards under the WPCO. The design of efficient silt removal facilities should be based on the guidelines in Appendix A1 of ProPECC Note PN 1/94. Sizes may vary depending upon the flow rate. The detailed design of the sand/silt traps should be undertaken by the Contractor prior to the commencement of construction.

All drainage facilities and erosion and sediment control structures should be regularly inspected and maintained to ensure proper and efficient operation at all times and particularly during rainstorms. Deposited silt and grit should be regularly removed, at the onset of and after each rainstorm to ensure that these facilities are functioning properly at all times.

Measures should be taken to minimize the ingress of site drainage into excavations. If excavation of trenches in wet periods is necessary, they should be dug and backfilled in short sections wherever practicable. Water pumped out from foundation excavations should be discharged into storm drains via silt removal facilities.

If surface excavation works cannot be avoided during the wet season (April to September), temporarily exposed slope/soil surfaces should be covered by tarpaulin or other means, as far as practicable, and temporary access roads should be protected by crushed stone or gravel, as excavation proceeds. Interception channels should be provided (e.g. along the crest/edge of the excavation) to prevent storm runoff from washing across exposed soil surfaces. Arrangements should always be in place to ensure that adequate surface protection measures can be safely carried out well before the arrival of a rainstorm. Other measures that need to be implemented before, during and after rainstorms are summarized in ProPECC Note PN 1/94.

The overall slope of the site should be kept to a minimum to reduce

the erosive potential of surface water flows.
All vehicles and plant should be cleaned before leaving a construction site to ensure no earth, mud, debris and the like is
deposited by them on roads. An adequately designed and sited wheel washing facility should be provided at construction site exit where practicable. Wash-water should have sand and silt settled out and removed regularly to ensure the continued efficiency of the process. The section of access road leading to, and exiting from, the wheel-wash bay to the public road should be paved with sufficient backfall toward the wheel-wash bay to prevent vehicle tracking of soil and silty water to public roads and drains.
Open stockpiles of construction materials or construction wastes on-site should be covered with tarpaulin or similar fabric during rainstorms. Measures should be taken to prevent the washing away of construction materials, soil, silt or debris into any drainage
system.
Manholes (including newly constructed ones) should be adequately covered and temporarily sealed so as to prevent silt, construction materials or debris being washed into the drainage system and stormwater runoff being directed into foul sewers.
Precautions should be taken at any time of the year when rainstorms are likely. Actions should be taken when a rainstorm is imminent or forecasted and actions to be taken during or after rainstorms are summarized in Appendix A2 of ProPECC Note PN 1/94. Particular attention should be paid to the control of silty surface runoff during storm events, especially for areas located near steep slopes.
Bentonite slurries used in piling or slurry walling should be reconditioned and reused wherever practicable. Temporary enclosed storage locations should be provided on-site for any unused bentonite that needs to be transported away after all the related construction activities are completed. The requirements in ProPECC Note PN 1/94 should be adhered to in the handling and disposal of bentonite slurries.
5.6.1.1 4.1 GoThca od site practices for works within water gathering grounds e following conditions should be complied, if there is any works to be rried out within the water gathering grounds: To minimize water quality impacts to the water gathering grounds Contractor Construction Works Sites within the water gathering Construction Phase ProPECC Note PN 1/94
Adequate measures should be implemented to ensure no pollution or siltation occurs to the catchwaters and catchments.
No earth, building materials, oil or fuel, soil, toxic materials or any materials that may possibly cause contamination to water gathering grounds are allowed to be stockpiled on site.
All surplus spoil should be removed from water gathering grounds as soon as possible.
Temporary drains with silt traps should be constructed at the site boundary before the commencement of any earthworks.
Regular cleaning of silt traps should be carried out to ensure proper operation at all time.
All excavated or filled surfaces which have the risk of erosion should always be protected form erosion.
Facilities for washing the wheels of vehicles before leaving the site should be provided.
Any construction plant which causes pollution to catchwaters or catchments due to the leakage of oil or fuel should be removed off site immediately.
No maintenance activities which may generate chemical wastes should be undertaken in the water gathering grounds. Vehicle maintenance should be confined to designated paved areas only and any spillages should be cleared up immediately using absorbents and waste oils should be collected in designated tanks prior to disposal off site. All storm water run-off from these areas should be discharged via oil/petrol separators and sand/silt removal traps.
Any soil contaminated with fuel leaked from plant should be removed off site and the voids arising from removal of contaminated soil should be replaced by suitable material approved by the Director of Water Supplies.
Provision of temporary toilet facilities and use of chemicals or insecticide of any kind are subject to the approval of the Director of Water Supplies.
Drainage plans should be submitted for approval by the Director of

grounds

Water Supplies.

An unimpeded access through the waterworks access road should always be maintained.
Earthworks near catchwaters or streamcourses should only be carried out in dry season between October and March,
Advance notice must be given before the commencement of works on site quoting WSD’s approval letter reference.
5.6.1.2 4.1 Good site practices of general construction activities

Construction solid waste, debris and refuse generated on-site should be collected, handled and disposed of properly to avoid entering any nearby stormwater drain. Stockpiles of cement and other construction materials should be kept covered when not being used.

Oils and fuels should only be stored in designated areas which have pollution prevention facilities. To prevent spillage of fuels and solvents to any nearby stormwater drain, all fuel tanks and storage areas should be provided with locks and be sited on sealed areas, within bunds of a capacity equal to 110% of the storage capacity of the largest tank. The bund should be drained of rainwater after a rain event.

To minimize water Contractor All construction Construction EIA Recommendation quality impacts works sites phase

5.6.1.3 4.1 Sewage effluent from construction workforce To minimize water Contractor All construction Construction EIA Recommendation quality impacts works sites with phase and Water Pollution

Temporary sanitary facilities, such as portable chemical toilets, should

on-site sanitary Control Ordinance be employed on-site where necessary to handle sewage from the

facilities (WPCO)

workforce. A licensed contractor should be employed to provide appropriate and adequate portable toilets and be responsible for appropriate disposal and maintenance.

5.6.1.4 4.1 Hydrogeological Impact To minimize water Contractor Construction Construction EIA Recommendation quality impacts works sites of phase and WPCO

Grout injection works would be conducted before blasting, for sealing a the drill and limited area around the tunnel with a grout of a suitable strength for blast tunnel

controlling the potential groundwater inflows. The pre-injection grouting method would be supplemented by post-injection grouting where necessary to further enhance the groundwater inflow control. On-site treatment for the groundwater ingress pumped out would be required to remove any contamination by grouting materials before discharge off-site.

Water Quality Impact (Operation)

No mitigation measure is required.

Sewage and Sewerage Treatment Impact (Construction)

6.7 5 The sewage generated by the on-site workforce should be collected in chemical toilets and disposed of off-site by a licensed waste collector. To minimize water quality impacts Contractor All construction works sites with on-site sanitary facilities Construction phase EIA recommendation and WPCO
Sewage and Sewerage Treatment Impact (Operation)
6.6.3 5 Sewage generated by the BCP and Chuk Yuen Village Resite will be collected and treated by the proposed on-site sewage treatment facility using Membrane Bioreactor treatment with a portion of the treated wastewater reused for irrigation and flushing within the BCP. To minimize water quality impacts DSD BCP Operation phase EIA recommendation and WPCO
6.5.3 5 Sewage generated from the Administration Building will be discharged to the existing local sewerage system. To minimize water quality impacts DSD Administration Building Operation phase EIA recommendation and WPCO
Waste Management Implication (Construction)
7.6.1.1 6 Good Site Practices To minimize Construction Construction EIA recommendation;
Adverse impacts related to waste management such as potential hazard, air, odour, noise, wastewater discharge and public transport as mentioned in section 3.4.7.2 (ii)(c) of the Study Brief are not expected to arise, provided that good site practices are strictly followed. Recommendations for good site practices during the construction activities include: Nomination of an approved person, such as a site manager, to be responsible for good site practices, arrangements for collection and effective disposal to an appropriate facility, of all wastes generated at the site adverse environmental impact works sites (general) Phase Waste Disposal Ordinance; Waste Disposal (Chemical Wastes) (General) Regulation; and ETWB TC(W) No. 19/2005, Environmental Management on Construction Site
Training of site personnel in proper waste management and chemical handling procedures
Provision of sufficient waste disposal points and regular collection of waste
Dust suppression measures as required under the Air Pollution Control (Construction Dust) Regulation should be followed as far as practicable. Appropriate measures to minimise windblown litter and dust/odour during transportation of waste by covering trucks or in enclosed containers
General refuse shall be removed away immediately for disposal. As

such odour is not anticipated to be an issue to distant sensitive

receivers

Provision of wheel washing facilities before the trucks leaving the works area so as to minimise dust introduction from public road
Covers and water spraying system should be provided for the stockpiled C&D material to prevent dust impact or being washed away
Designate different locations for storage of C&D material to enhance reuse
Well planned programme for transportation of C&D material to lessen the off-site traffic impact. Well planned delivery programme for offsite disposal and imported filling material such that adverse noise impact from transporting of C&D material is not anticipated
Site practices outlined in ProPECC PN 1/94 Construction Site Drainage should be adopted as far as practicable, such as cleaning and maintenance of drainage systems regularly
Provision of cover for the stockpile material, sand bag or earth bund as barrier to prevent material from washing away and entering the drains
7.6.1.2 6 Waste Reduction Measures To reduce the Contractor Construction Construction EIA recommendation
Good management and control can prevent the generation of a significant amount of waste. Waste reduction is best achieved at the quantity of wastes works sites (General) Phase and Waste Disposal Ordinance
planning and design stage, as well as by ensuring the implementation
of good site practices. Recommendations to achieve waste reduction
include:
Segregation and storage of different types of waste in different
containers, skips or stockpiles to enhance reuse or recycling of
materials and their proper disposal
Encourage collection of aluminium cans by providing separate
labelled bins to enable this waste to be segregated from other
general refuse generated by the work force
Proper storage and site practices to minimise the potential for
damage or contamination of construction materials
Plan and stock construction materials carefully to minimise amount
7.6.1.3 7.6.1.4 6 6 of waste generated and avoid unnecessary generation of waste In addition to the above measures, specific mitigation measures are recommended below for the identified waste arising to minimise environmental impacts during handling, transportation and disposal of these wastes. C&D Materials In order to minimise impacts resulting from collection and transportation of C&D material for off-site disposal, the excavated materials should be reused on-site as backfilling material as far as practicable. The surplus rock and other inert C&D material would be disposed of at the Government’s Public Fill Reception Facilities (PFRFs) at Tuen Mun Area 38 for beneficial use by other projects in the HKSAR as the last resort. C&D waste generated from general site clearance and tree felling works would require disposal to the designated landfill site. Other mitigation requirements are listed below: A Waste Management Plan should be prepared and implemented in accordance with ETWB TC(W) No. 19/2005 Environmental Management on Construction Site; and In order to monitor the disposal of C&D material and solid wastes at public filling facilities and landfills, and to control fly-tipping, a trip-ticket system (e.g. ETWB TCW No. 31/2004) should be included. General refuse General refuse should be stored in enclosed bins or compaction units separated from other C&D material. A reputable waste collector is to be employed by the Contractor to remove general refuse from the site separately. Preferably an enclosed and covered area should be provided to reduce the occurrence of 'wind blown' litter. To minimize impacts resulting from C&D material To minimize impacts resulting from collection and transportation of general refuse for off-site disposal Contractor Contractor Construction Works Sites (General) Construction works sites (General) Construction Phase Construction phase EIA recommendation; Waste Disposal Ordinance; and ETWB TCW No. 31/2004 Waste Disposal Ordinance and Public Health and Municipal Services Ordinance Public Cleansing and Prevention of Nuisances Regulation
7.6.1.5 6 Chemical waste If chemical wastes are produced at the construction site, the Contractor will be required to register with the EPD as a chemical waste producer and to follow the guidelines stated in the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes. Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately. Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical To minimize impacts resulting from collection and transportation of chemical waste for off-site disposal Contractor Construction works sites (General) Construction phase Waste Disposal (Chemical Waste) (General) Regulation and Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes