8.             Implementation Schedule and Recommended Mitigation Measures

Table 8.1           Implementation schedule of Recommended Mitigation Measures

EIA Ref.

Recommended Mitigation Measures

Objectives of the Recommended Measures & Main Concern to Address

Who to implement the measures?

Location of the measure

When to implement the measures?

What requirements or standards for the measure to achieve?

Water Quality Impact (Construction Phase)

 

 

 

 

 

S3.142

Dredging should be carried out by closed grab dredger.

To minimize release of sediment and contaminants during dredging.

Contractor

Dredging works areas in Causeway Bay Typhoon Shelter (CBTS)

Construction Phase

EIAO-TM, WPCO

S3.142

All temporary reclamation works should adopt an approach where temporary seawalls will first be formed to enclose each phase of the temporary reclamation.  Installation of diaphragm wall on temporary reclamation as well as any bulk filling will proceed behind the completed seawall.  Any gaps that may need to be provided for marine access should be shielded by silt curtains to control sediment plume dispersion away from the site.  Demolition of temporary reclamation including the demolition of the diaphragm wall and dredging to the existing seabed levels should be carried out behind the temporary seawall.  Temporary seawall should be removed after completion of all excavation and dredging works for demolition of the temporary reclamation.

To minimize loss of fines and contaminants during temporary reclamations

Contractor

Temporary reclamation works areas in CBTS

Construction Phase

EIAO-TM, WPCO

S3.142

During construction of the temporary reclamation, temporary seawall should be partially constructed to protect the nearby seawater intakes from further dredging activities.  For example, the seawalls along the southeast and northeast boundaries of PW1.1 should be constructed first (above high water mark) so that the seawater intake at the inner water would be protected from the impacts from the remaining dredging activities along the northwest boundary.

To minimize water quality impact upon the cooling water intakes in CBTS from temporary reclamation works

Contractor

Temporary reclamation works areas in CBTS

Construction Phase

EIAO-TM, WPCO

S3.142

Silt curtains should be deployed to fully enclose the closed grab dredger during any dredging operation within the CBTS.

 

To minimize loss of fines and contaminants during dredging in CBTS

Contractor

Dredging works areas in CBTS

Construction Phase

EIAO-TM, WPCO

S3.142

Silt screens will be installed at all the cooling water intakes within the CBTS during temporary reclamation and dredging within the typhoon shelter.

 

To minimize water quality impact upon the cooling water intakes in CBTS from marine construction activities

Contractor

Cooling water intakes inside CBTS

Construction Phase

EIAO-TM, WPCO

S3.143

No more than two closed grab dredgers should be operated for dredging within the CBTS at any time.  Moreover, the combined production rate of all concurrent dredging works to be undertaken within the CBTS shall not exceed 6,000 m3 per day at all times throughout the entire construction period.

To minimize loss of fines and contaminants during dredging in CBTS

Contractor

Temporary reclamation and dredging works areas in CBTS

Construction Phase

EIAO-TM, WPCO

S3.145

The following good site practices should be undertaken during sand filling, public filling and dredging:

Ÿ mechanical grabs, if used, should be designed and maintained to avoid spillage and sealed tightly while being lifted.  For dredging of any contaminated mud, closed watertight grabs must be used;

Ÿ all vessels should be sized so that adequate clearance is maintained between vessels and the seabed in all tide conditions, to ensure that undue turbidity is not generated by turbulence from vessel movement or propeller wash;

Ÿ all hopper barges and dredgers should be fitted with tight fitting seals to their bottom openings to prevent leakage of material;

Ÿ construction activities should not cause foam, oil, grease, scum, litter or other objectionable matter to be present on the water within the site or dumping grounds; and

Ÿ loading of barges and hoppers should be controlled to prevent splashing of dredged material into the surrounding water.  Barges or hoppers should not be filled to a level that will cause the overflow of materials or polluted water during loading or transportation.

To minimize loss of fines and contaminants from dredging / filling

Contractor

Temporary reclamation and dredging works areas in CBTS

Construction Phase

EIAO-TM, WPCO

S3.146

The following mitigation measures are proposed to minimize the potential water quality impacts from the construction works at or close to the seafront:

Ÿ Temporary storage of construction materials (e.g. equipment, filling materials, chemicals and fuel) and temporary stockpile of construction and demolition materials should be located well away from the seawater front and storm drainage during carrying out of the works.

Ÿ Stockpiling of construction and demolition materials and dusty materials should be covered and located away from the seawater front and storm drainage.

Ÿ Construction debris and spoil should be covered up and/or disposed of as soon as possible to avoid being washed into the nearby receiving waters.

To minimize release of construction wastes from construction works at or close to the seafront

Contractor

Construction works at or close to the seafront

Construction Phase

EIAO-TM, WPCO

S3.147

Silt curtains should be installed around the working area for the marine piling works for construction of the temporary jetty as necessary to minimize the release of sediment and construction wastes. All wastewater generated from the piling activities should be collected by a derrick lighter or other collection system and be treated before controlled discharge. Spoil from the piling activities should be collected by sealed hopper barges for proper disposal.

To minimize water quality impacts from piling works for construction of the temporary jetty

Contractor

Piling area at the piling location

Construction Phase

EIAO-TM, WPCO

S3.148

Regular maintenance and refuse collection should be performed at the silt screens deployed at the seawater intakes at regular intervals on a daily basis.  The Contractor should be responsible for keeping the water behind the silt screen free from floating rubbish and debris during the impact monitoring period.

To avoid the pollutant and refuse entrapment problems at the silt screens to be installed at the water intakes

Contractor

Proposed silt screens at cooling water intakes inside CBTS

Construction Phase

EIAO-TM, WPCO

S3.149

Collection and removal of floating refuse should be performed within the marine construction areas at regular intervals on a daily basis.  The Contractor should be responsible for keeping the water within the site boundary and the neighbouring water free from rubbish during the dredging works.

To minimize water quality impacts from illegal dumping and littering from marine vessels and runoff from the coastal areas

Contractor

All marine works areas

Construction Phase

EIAO-TM, WPCO, WDO

S3.150 to 3.169

The site practices outlined in ProPECC PN 1/94 “Construction Site Drainage” should be followed where practicable. 

To minimize water quality impacts from construction site runoff and general construction activities

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS, WDO, ProPECC PN 1/94

S3.170

There is a need to apply to EPD for a discharge licence for discharge of effluent from the construction site under the WPCO.  The discharge quality must meet the requirements specified in the discharge licence.  All the runoff and wastewater generated from the works areas should be treated so that it satisfies all the standards listed in the TM-DSS.  Minimum distances of 100 m should be maintained between the discharge points of construction site effluent and the existing seawater intakes.  The beneficial uses of the treated effluent for other on-site activities such as dust suppression, wheel washing and general cleaning etc., can minimise water consumption and reduce the effluent discharge volume.  If monitoring of the treated effluent quality from the works areas is required during the construction phase of the Project, the monitoring should be carried out in accordance with the WPCO license which is under the ambit of Regional Office (RO) of EPD.

To minimize water quality impact from effluent discharges from construction sites

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS

S3.171 & 3.172

Construction work force sewage discharges on site are expected to be connected to the existing trunk sewer or sewage treatment facilities.  If disposal of sewage to public sewerage system is not feasible, appropriate numbers of portable toilets shall be provided by a licensed contractor to serve the construction workers over the construction site to prevent direct disposal of sewage into the water environment.  The Contractor shall also be responsible for waste disposal and maintenance practices.

Notices should be posted at conspicuous locations to remind the workers not to discharge any sewage or wastewater into the nearby environment. 

To minimize water quality impacts due to sewage generated from construction workforce

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS, WDO

S3.173

Contractor must register as a chemical waste producer if chemical wastes would be produced from the construction activities.  The Waste Disposal Ordinance (Cap 354) and its subsidiary regulations in particular the Waste Disposal (Chemical Waste) (General) Regulation should be observed and complied with for control of chemical wastes.

To minimize water quality impact from accidental spillage of chemical

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS, WDO

S3.174

Any service shop and maintenance facilities should be located on hard standings within a bunded area, and sumps and oil interceptors should be provided.  Maintenance of vehicles and equipment involving activities with potential for leakage and spillage should only be undertaken within the areas appropriately equipped to control these discharges.

To minimize water quality impact from accidental spillage of chemical

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS, WDO

S3.175

Disposal of chemical wastes should be carried out in compliance with the Waste Disposal Ordinance.  The “Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes” published under the Waste Disposal Ordinance details the requirements to deal with chemical wastes.  General requirements are given as follows:

Ÿ Suitable containers should be used to hold the chemical wastes to avoid leakage or spillage during storage, handling and transport.

Ÿ Chemical waste containers should be suitably labelled, to notify and warn the personnel who are handling the wastes, to avoid accidents.

Ÿ Storage area should be selected at a safe location on site and adequate space should be allocated to the storage area.

To minimize water quality impact from accidental spillage of chemical

Contractor

All construction works areas

Construction Phase

EIAO-TM, WPCO, TM-DSS, WDO

Noise Impact (Construction Phase)

 

 

 

 

 

S4. 30

The following good site practices should be implemented:

Ÿ Only well-maintained plant should be operated on-site and plant should be serviced regularly during the construction program

Ÿ Silencers or mufflers on construction equipment should be utilized and should be properly maintained during the construction program

Ÿ Mobile plant, if any, should be sited as far from NSRs as possible

Ÿ Machines and plant (such as trucks) that may be in intermittent use should be shut down between work periods or should be throttled down to a minimum

Ÿ Plant known to emit noise strongly in one direction should, wherever possible, be orientated so that the noise is directed away from the nearby NSRs

Ÿ Material stockpiles and other structures should be effectively utilized, wherever practicable, in screening noise from on-site construction activities.

To reduce construction noise

impact

 

Contractor

 

All works areas

 

Construction

phase

 

EIAO-TM,

NCO

 

S4.31 – S4.32 & Table 4.7

The following quiet PME are recommended for the construction activities:

·            Air Compressor  

·            Bulldozer  

·            Concrete Pump

·            Concrete Lorry Mixer  

·            Crane  

·            Dump Truck  

·            Excavator  

·            Generator  

·            Hand-held  Breaker  

·            Poker Vibrator  

·            Roller  

·            Trucks  

 

To reduce construction noise

impact

 

Contractor

 

All works areas

 

Construction

phase

 

EIAO-TM,

NCO

 

S4.33 – S4.35 & Table 4.8

Movable noise barrier should be used for the following PME:

·            Air Compressor

·            Bar Bender

·            Bentonite Plants

·            Concrete pump

·            Diaphragm Wall Rigs

·            Excavator

·            Poker Vibrator

 

To reduce construction noise

impact

 

Contractor

 

Affected works areas showing exceedance during un-mitigated scenario

 

Construction

phase

EIAO-TM,

NCO

 

Construction Dust Impact

 

 

 

 

 

S5.43

Watering once on construction areas for every working hour

To minimize dust impact

Contractor

Temporary reclamation area in CBTS

Construction phase

APCO

S5.43

Covering/paving the southwest retained area of temporary reclamation once filling is completed

 

To minimize dust impact

Contractor

southwest retained area of temporary reclamation

Construction phase

APCO

S5.44

Dust suppression measures stipulated in the Air Pollution Control (Construction Dust) Regulation and good site practices:

Ÿ Use of regular watering, with complete coverage, to reduce dust emissions from exposed site surfaces and unpaved roads, particularly during dry weather.

Ÿ Use of frequent watering for particularly dusty construction areas and areas close to ASRs.

Ÿ Side enclosure and covering of any aggregate or dusty material storage piles to reduce emissions.  Where this is not practicable owing to frequent usage, watering shall be applied to aggregate fines.

Ÿ Open stockpiles shall be avoided or covered.  Where possible, prevent placing dusty material storage piles near ASRs.

Ÿ Tarpaulin covering of all dusty vehicle loads transported to, from and between site locations.

Ÿ Establishment and use of vehicle wheel and body washing facilities at the exit points of the site.

Ÿ Provision of wind shield and dust extraction units or similar dust mitigation measures at the loading points, and use of water sprinklers at the loading area where dust generation is likely during the loading process of loose material, particularly in dry seasons/ periods.

Ÿ Provision of not less than 2.4m high hoarding from ground level along site boundary where adjoins a road, streets or other accessible to the public except for a site entrance or exit.

Ÿ Imposition of speed controls for vehicles on site haul roads.

Ÿ Where possible, routing of vehicles and positioning of construction plant should be at the maximum possible distance from ASRs.

Ÿ Every stock of more than 20 bags of cement or dry pulverised fuel ash (PFA) should be covered entirely by impervious sheeting or placed in an area sheltered on the top and the 3 sides.

Ÿ Instigation of an environmental monitoring and auditing program to monitor the construction process in order to enforce controls and modify method of work if dusty conditions arise.

To minimize dust impacts

Contractor

Temporary reclamation area in CBTS

Construction phase

APCO and Air Pollution Control (Construction Dust) Regulation

Waste Management Implications (Construction Phase)

 

 

 

 

 

6.62

Good Site Practices and Waste Reduction Measures

-       Prepare a Waste Management Plan approved by the Engineer/Supervising Officer of the Project based on current practices on construction sites;

-       Training of site personnel in, site cleanliness, proper waste management and chemical handling procedures;

-       Provision of sufficient waste disposal points and regular collection of waste;

-       Appropriate measures to minimize windblown litter and dust during transportation of waste by either covering trucks or by transporting wastes in enclosed containers;

-       Regular cleaning and maintenance programme for drainage systems, sumps and oil interceptors; and

-       Separation of chemical wastes for special handling and appropriate treatment.

To enhance water management practice and achieve waste reduction.

Contractor

All Work Sites

Construction Phase

Waste Disposal Ordinance (Cap. 354)

 

Land (Miscellaneous Provisions) Ordinance (Cap. 28)

 

ETWB TC(W) No.31/2004

6.63

Good Site Practices and Waste Reduction Measures (con’t)

-       Sorting of demolition debris and excavated materials from demolition works to recover reusable/ recyclable portions (i.e. soil, broken concrete, metal etc.);

-       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 aluminum cans by providing separate labeled bins to enable this waste to be segregated from other general refuse generated by the workforce;

-       Proper storage and site practices to minimize the potential for damage or contamination of construction materials;

-       Plan and stock construction materials carefully to minimize amount of waste generated and avoid unnecessary generation of waste; and

-       Training should be provided to workers about the concepts of site cleanliness and appropriate waste management procedures, including waste reduction, reuse and recycle.

To achieve waste reduction

Contractor

All Work Sites

Construction Phase

Waste Disposal Ordinance (Cap. 354)

 

Land (Miscellaneous Provisions) Ordinance (Cap. 28)

6.64

 Good Site Practices and Waste Reduction Measures (con’t)

-       The Contractor shall prepare and implement an EMP in accordance with ETWB TCW No. 19/2005.  Such management plan should incorporate site specific factors, such as the designation of areas for segregation and temporary storage of reusable and recyclable materials.  The EMP should be submitted to the Engineer for approval.  The Contractor should implement the waste management practices in the EMP throughout the construction stage of the Project.  The EMP should be reviewed regularly and updated by the Contractor, preferably in a monthly basis.

To enhance water management practice and achieve waste reduction.

Contractor

All Work Sites

Construction Phase

ETWB TCW No. 19/2005

6.66

Storage, Collection and Transportation of Waste

-       Waste, such as soil, should be handled and stored well to ensure secure containment, thus minimizing the potential of pollution;

-       Maintain and clean storage areas routinely;

-       Stockpiling area should be provided with covers and water spraying system to prevent materials from wind-blown or being washed away; and

-       Different locations should be designated to stockpile each material to enhance reuse.

To minimize potential adverse environmental impacts arising from waste storage

Contractor

Work Sites

Construction Phase

-

6.67

Storage, Collection and Transportation of Waste (con’t)

-       Waste haulier with appropriate permits should be employed by the Contractor for the collection and transportation of waste from works areas to respective disposal outlets. 

To minimize potential adverse environmental impacts arising from waste collection and disposal

Contractor

Waste storage area.

Construction Phase

-

6.68

Storage, Collection and Transportation of Waste (con’t)

-       Implementation of trip ticket system with reference to ETWB TC(W) No.31/2004 to monitor disposal of waste and to control fly-tipping at PFRFs or landfills.  A recording system for the amount of waste generated, recycled and disposed (including disposal sites) should be proposed.

To minimize potential adverse environmental impacts arising from waste collection and disposal

Contractor

Work Sites

Construction Phase

ETWB TC(W) No.31/2004

6.70 – 6.73

Sorting of C&D Materials

-       Sorting to be performed to recover the inert materials, reusable and recyclable materials before disposal off-site. 

-       Specific areas should be provided by the Contractors for sorting and to provide temporary storage areas for the sorted materials. 

-       The C&D materials should at least be segregated into inert and non-inert materials, in which the inert portion could be reused and recycled as far as practicable before delivery to PFRFs as mentioned for beneficial use in other projects.  While opportunities for reusing the non-inert portion should be investigated before disposal of at designated landfills.

-       Possibility of reusing the spoil in the Project will be continuously investigated in the construction stage.

To minimize potential adverse environmental impacts during the handling, transportation and disposal of C&D materials

Contractor

All work Sites

Construction Phase

ETWB TCW No. 31/2004

ETWB TCW No. 33/2002

ETWB TCW No. 19/2005

 

6.75

Sediments

-       The basic requirements and procedures for dredged sediment disposal specified under PNAP 252 shall be followed. MFC manages disposal facilities in Hong Kong for the dredged sediment, while EPD is the authority issuing marine dumping permits under the Dumping at Sea Ordinance.

 

To ensure the sediment to be disposed of in an authorized and least impacted way

Contractor

All works areas with sediments concern

Construction Phase

PNAP 252

6.76

Sediments (con’t)

-       The Project Proponent should agree in advance with MFC of CEDD on the site allocation by submitting a Construction & Demolition Material Management Plan. The contractor for the dredging works shall then apply for the site allocations of marine sediment disposal based on the prior agreement with MFC/CEDD. A request for reservation of sediment disposal space has been submitted to MFC for onward discussions of disposal approaches and feasible disposal sites. The Project Proponent is also responsible for application of all necessary permits from the relevant authorities, including the dumping permit as required under DASO from EPD, for the disposal of dredged sediment prior to the commencement of the dredging works.

To determine the best handling and disposal option of the sediments

MTR / Contractor

All works areas with sediments concern

Prior to the start of dredging works

PNAP 252;

Dumping at Sea Ordinance

6.77 – 6.81

Sediments (con’t)

-       Requirements of the Air Pollution Ordinance (Construction Dust) Regulation, where relevant, shall be adhered to during dredging, transportation and disposal of sediments.

-       Stockpiling of contaminated sediments should be avoided as far as possible. If temporary stockpiling of contaminated sediments is necessary, the dredged sediment should be covered by tarpaulin and the area should be placed within earth bunds or sand bags to prevent leachate from entering the ground, nearby drains and/or surrounding water bodies.  The stockpiling areas should be completely paved or covered by linings in order to avoid contamination to underlying soil or groundwater.  Separate and clearly defined areas should be provided for stockpiling of contaminated and uncontaminated materials.  Leachate, if any, should be collected and discharged according to the Water Pollution Control Ordinance (WPCO).

-       In order to minimise the potential odour / dust emissions during dredging and transportation of the sediment, the dredged sediments should be properly covered when placed on barges.  Loading of the dredged sediment to the barge should be controlled to avoid splashing and overflowing of the sediment slurry to the surrounding water.

-       The barge transporting the sediments to the designated disposal sites should be equipped with tight fitting seals to prevent leakage and should not be filled to a level that would cause overflow of materials or laden water during loading or transportation.  In addition, monitoring of the barge loading shall be conducted to ensure that loss of material does not take place during transportation. Transport barges or vessels shall be equipped with automatic self-monitoring devices as specified by the DEP.

-       In order to minimise the exposure to contaminated materials, workers should wear appropriate personal protective equipments (PPE) when handling contaminated sediments.  Adequate washing and cleaning facilities should also be provided on site.

To ensure handling  of sediments are in accordance to statutory requirements

Contractor

Work Sites, Sediment disposal sites

Construction Phase

PNAP 252

 

Dumping at Sea Ordinance

6.82

Sediments (con’t)

The dredging work and associate sediment handling under this Project will be undertaken together with the CWB project by Highways Department and geosynthetic containment will be adopted to handle Type 3 sediments.

To ensure handling  of sediments are in accordance to statutory requirements

Contractor

Work Sites, Sediment disposal sites

Construction Phase

PNAP 252

Dumping at Sea Ordinance

6.86

Containers for Storage of Chemical Waste

The Contractor should register with 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. Containers used for storage of chemical waste should:

-       Be compatible with the chemical wastes being stored, maintained in good condition and securely sealed;

-       Have a capacity of less than 450 litters unless the specifications have been approved by EPD; and

-       Display a label in English and Chinese in accordance with instructions prescribed in Schedule 2 of the Waste Disposal (Chemical Waste) (General) Regulation.

To register with EPD as a Chemical waste producer and store chemical waste in appropriate  containers

Contractor

Chemical waste storage area

Construction Phase

Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes

6.87

Chemical Waste Storage Area

-       Be clearly labeled to indicate corresponding chemical characteristics of the chemical waste and used for storage of chemical waste only;

-       Be enclosed on at least 3 sides;

-       Have an impermeable floor and bunding, of capacity to accommodate 110% of the volume of the largest container or 20% by volume of the chemical waste stored in that area, whichever is the greatest;

-       Have adequate ventilation;

-       Be covered to prevent rainfall from entering; and

-       Be properly arranged so that incompatible materials are adequately separated.

To prepare appropriate  storage areas for chemical waste at works areas

Contractor

Chemical waste storage area

Construction Phase

Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes

6.88

Labelling of Chemical Waste

-       Lubricants, waste oils and other chemical wastes would be generated during the maintenance of vehicles and mechanical equipments.  Used lubricants should be collected and stored in individual containers which are fully labeled in English and Chinese and stored in a designated secure place. 

To clearly label the chemical waste at works areas

Contractor

Chemical waste storage area

Construction Phase

Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes

6.89

Collection and Disposal of Chemical Waste

-       A trip-ticket system should be operated in accordance with the Waste Disposal (Chemical Waste) (General) Regulation to monitor all movements of chemical waste.  The Contractor shall employ a licensed collector to transport and dispose of the chemical wastes, to either the approved CWTC at Tsing Yi, or another licensed facility, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.

To monitor the generation, reuse and disposal of chemical waste

Contractor

Work Sites with chemical waste production

Construction Phase

Waste Disposal (Chemical Waste) (General) Regulation

6.90

General Refuse

-       General refuse should be stored in enclosed bins or compaction units separate from C&D materials and chemical waste.  A reputable waste collector should be employed by the contractor to remove general refuse from the site, separately from C&D materials and chemical wastes.  Preferably, an enclosed and covered area should be provided to reduce the occurrence of windblown light material.

To properly store and separate from other C&D materials for subsequent collection and disposal

Contractor

All Work Sites

Construction Phase

-

6.91

General Refuse (con’t)

-       The recyclable component of general refuse, such as aluminum cans, paper and cleansed plastic containers should be separated from other waste.  Provision and collection of recycling bins for different types of recyclable waste should be set up by the Contractor.  The Contractor should also be responsible for arranging recycling companies to collect these materials.

To facilitate recycling of recyclable portions of refuse

Contractor

All Work Sites

Construction Phase

-

6.92

General Refuse (con’t)

-       The Contractor should carry out an education programme for workers in avoiding, reducing, reusing and recycling of materials generation.  Posters and leaflets advising on the use of the bins should also be provided in the sites as reminders.

To raise workers’ awareness on recycling issue

Contractor

All Work Sites

Construction Phase

-