6.1             Introduction

6.1.1   This section identifies the types of wastes that are likely to be generated during the construction phase of the CWB & IECL and evaluates the potential environmental impacts that may result from these waste arisings.  Mitigation measures and good site practice, including waste handling, storage and disposal, will be recommended with reference to the applicable waste legislation and guidelines.

6.2             Environmental Legislation, Policies, Plans, Standards and Criteria

6.2.1       The criteria and guidelines for assessing waste management implications are outlined in the Annex 7 and Annex 15 of the Technical Memorandum on Environmental Impact Assessment Ordinance (EIAO-TM), respectively.

6.2.2       The following legislation relates to the handling, treatment and disposal of wastes in the Hong Kong SAR and will be used in assessing potential impacts:

·          Waste Disposal Ordinance (Cap. 354);

·          Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354);

·          Land (Miscellaneous Provisions) Ordinance (Cap. 28);

·          Dumping at Sea Ordinance (Cap. 466); and

·          Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention of Nuisances (Urban Council) and (Regional Council) By-laws.

6.2.3       The following documents, circulars and guidelines which relate to waste management and disposal in Hong Kong SAR will also be referred to during this study:

·          Waste Disposal Plan for Hong Kong (December 1989), Planning, Environment and Lands Branch, Hong Kong Government Secretariat;

·          Environmental Guidelines for Planning in Hong Kong (1990), Hong Kong Planning and Standards Guidelines, Hong Kong Government;

·          New Disposal Arrangements for Construction Waste (1992), Environmental Protection Department and Civil Engineering Department;

·          Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), Environmental Protection Department;

·          Waste Reduction Framework Plan, 1998-2007 (1998), Planning, Environment and Lands Branch, Hong Kong Government Secretariat;

·          Works Branch Technical Circular No. 2/93, Public Dumps;

·          Works Bureau Technical Circular No. 2/93B, Public Filling Facilities;

·          Works Branch Technical Circular No. 16/96, Wet Soil in Public Dumps;

·          Works Bureau Technical Circular No. 4/98 & 4/98A, Use of Public Fill in Reclamation and Earth Filling Projects;

·          Works Bureau Technical Circular No. 5/98, On Site Sorting of Construction Waste on Demolition Sites;

·          Works Bureau Technical Circular No. 5/99 & 5/99A, Trip-ticket System for Disposal of Construction and Demolition Material;

·          Works Bureau Technical Circular No. 19/99, Metallic Site Hoardings and Signboards;

·          Works Bureau Technical Circular No. 25/99, 25/99A & 25/99B, Incorporation of Information on Construction and Demolition Material Management in Public Works Sub-committee Papers;

·          Works Bureau Technical Circular No. 3/2000, Management of Dredged / Excavated Sediment;

·          Works Bureau Technical Circular No. 12/2000, Fill Management; and.

·          Works Bureau Technical Circular No. 29/2000, Waste Management Plan.

Waste Management

6.2.4       The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes.  Construction waste is not directly defined in the WDO but is considered to fall within the category of “trade waste”.  Trade waste is defined as waste from any trade, manufacturer or business, or any waste building, or civil engineering materials, but does not include animal waste.  Under the WDO, wastes can be disposed of at sites licensed by the EPD.

6.2.5       The Public Cleansing and Prevention of Nuisance By-Laws provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.

Chemical Waste

6.2.6       Under the Waste Disposal (Chemical Waste) (General) Regulations all producers of chemical waste must register with the EPD and treat their wastes, either utilising on-site plant licensed by the EPD, or arranging for a licensed collector to transport the wastes to a licensed facility.  The regulation also prescribes the storage facilities to be provided on site, including labelling and warning signs, and requires the preparation of written procedures and training to deal with emergencies such as spillages, leakages or accidents arising from the storage of chemical wastes.

Construction and Demolition (C&D) Materials

6.2.7       The current policy related to the dumping of construction and demolition (C&D) material is documented in the Works Branch Technical Circular No. 2/93, ‘Public Dump’. Construction and demolition materials that are wholly inert, namely public fill, should not be disposed of to landfill, but taken to public filling areas which usually form part of reclamation schemes.  The Land (Miscellaneous Provisions) Ordinance requires that dumping licences are obtained by individual or companies who deliver public fill to public filling areas.  The licences are issued by the Civil Engineering Department (CED) under delegated powers from the Director of Lands.

6.2.8       In addition to the Works Branch Technical Circular, EPD and CED have produced a leaflet titled ‘New Disposal Arrangements for Construction Waste’ (1992) which states that C&D material with less than 30% by weight of inert material (that is, public fill) will be accepted at landfill.  If the material contains more than 30% inert material, the waste must be sorted with suitable material and sent to public filling area and the non-inert material (that is, C&D waste) sent to landfill for final disposal.

6.3             Assessment Methodology

6.3.1       The criteria for evaluating the potential construction waste management implications are set out in Annex 7 of the EIAO-TM.  The methods for assessing potential waste management impacts during construction follow those presented in Annex 15 of the EIAO-TM and include the following:

·        estimation of the types and quantities of the wastes generated, and timing of these waste arisings;

·        assessment of potential impacts from the management of solid waste with respect to potential hazards, air and odour emissions, noise, wastewater discharges and transport;

·        measures for reducing waste generation;

·        possibility of on-site and off-site reuse;

·        adequate area on-site for waste segregation and storage;

·        quantities of wastes to be disposed of off-site;

·        possible disposal options; and

·        impacts on the capacity of waste collection, transfer and disposal facilities.

6.4             Identification of Environmental Impacts

6.4.1       Activities during the construction phase of the CWB & IECL will result in the generation of a variety of wastes that can be divided into distinct categories based on their nature and the options for their disposal.  These include:

·        construction and demolition material (including excavated material);

·        excavated sediment;

·        chemical waste; and

·        general refuse.

6.4.2       The definitions for each of these categories and the nature of their arisings and potential impacts are discussed below.

6.5             Prediction and Evaluation of Environmental Impacts

Construction and Demolition (C&D) Material

Excavated Material from Works managed by Highways Department

6.5.1       Excavated material will comprise primarily public fill and marine sand that has been used as reclamation fill in the CRIII and WDII.  From the Central Reclamation Phase I (CRI) area, excavated material will be mainly marine sand. The estimates on the volume of excavated material to be generated from tunnel works, road formation and foundation earthworks are summarised in Table 6.1.

Table 6.1        Excavated Material from works managed by Highways Department



Volume of Excavated Material (m3)

Excavated Material to be Reused (m3)

Excavated Material to be Disposed Off-site (m3)



Central Interchange

Tunnel Works:

·         Eastbound Tunnel

·         Westbound Tunnel

·         Tunnel modification

Road Formation



























Dec 2005 – Jul 2006

Jul 2006 – Apr 2007


Feb 2007 – Feb 2008


Mar 2007 – Aug 2008







·         East Portal Area

·         IECL Foundation Earthworks











May 2008 – Aug 2010

May 2008 – Aug 2010






West Ventilation Building




Jun 2009 – Oct 2010

Central Ventilation Building




Jun 2009 – Oct 2010

East Ventilation and Administration Building




Jun 2009 – Oct 2010






6.5.1       The estimated total quantity of excavated material from the Central Interchange, IECL and tunnel buildings is 259,200m3 and out of which 35,130m3 will be reused on-site and 224,070m3 will be required to be disposed off-site. As the construction works for the CWB & IECL project mainly comprise highway structural works for the trunk road tunnel and  bridges and at grade slip roads the capacity to receive excavated material on site is limited and only about 14% can be reused as the backfill material for the foundation, tunnel, road formation and landscaping works.

6.5.2       It should be noted that according to current planning the WDII reclamation works will still be in progress at the time the surplus material from Central Interchange will need to be disposed off-site. As such, it may be possible that the surplus material from the Central Interchange identified to be disposed off-site could be used as fill material in WDII, depending on the programme of works that will actually take place at that time.  Given the likely inert nature of this material, reuse on-­site or in other reclamation works is not likely to have any unacceptable environmental impact.  Potential impacts associated with the excavated material are related to air quality and dust generation during excavation, stockpiling and transportation, which have been discussed in Section 3.


Excavated Material from Works entrusted to Territory Development Department

6.5.3       The section of tunnel box structure through CRIII and WDII areas will be constructed under entrustment to Territory Development Department in these two respective projects. The estimated quantities of excavated material are given in Table 6.2. 

Table 6.2        Excavated Material from Work Entrusted to Territory Development Department


Volume of Excavated Material (m3)

Volume of Excavated Material to be  Disposed Off-site (m3)

Central Reclamation Phase III



Excavated reclamation fill material from tunnel box construction

439,000 (1)

50,000 (1)

Wan Chai Development Phase II



Excavated reclamation fill material from tunnel box construction



Excavated ground fill material from tunnel construction




(1)    Atkins China Ltd. (May 2001).  Central Reclamation Phase III Comprehensive Feasibility Study for Minimum Option, Draft Final EIA Report Revision 03.

(2) Maunsell Consultants Asia Ltd. (May 2001).  Wan Chai Development Phase II Comprehensive Feasibility Study, EIA Report, Advance Final Version Revision B.


6.5.4       With reference to the CRIII EIA Report, the volume of excavated material from the entrusted tunnel works is about 439,000m3 and out of which 50,000m3 will be required to be disposed off-site. Most of the excavated material will be reused within the CRIII reclamation.  However, the 50,000m3 excavated material from the last portion of the tunnel works will need to be disposed off-site because most of the reclamation works within the CRIII areas will have been completed by that time.  It should be noted that according to the current planning the WDII reclamation works will still be in progress at the time the surplus excavated material from the CRIII project will need to be disposed off site.  As such, it may be possible that the surplus excavated material from the CRIII project identified to be disposed off site could be used as fill material in WDII, depending on the programme of works that will actually take place at that time.

6.5.1       The quantity of excavated material requiring off-site disposal arising from the CWB entrusted tunnel works within the WDII area is about 170,000m3 as indicated in the WDII EIA Report. This quantity was estimated with a view to maximizing the reuse of excavated material as reclamation fill for the WDII project.

6.5.2       The excavated material requiring off-site disposal will be generated from the tunnel sections at reclamation near Wan Chai waterfront, according to various programme constraints arising from the reprovisioning requirements of existing waterfront facilities. Upon completion of land formation, diaphragm wall construction will commence and be followed by excavation for tunnel construction.

6.5.3       According to the construction programme for the WDII project, all the reclamation filling will have been completed when the excavation for the last tunnel sections commences. Therefore, the quantity of excavated material after deducting those for backfilling for the proposed ground level roads will need to be disposed off-site.

C&D Material from New Building construction

6.5.4       Construction and demolition (C&D) material will be generated from new building construction and will comprise unwanted material generated during construction.  C&D material may include:

·        wood from formwork;

·        material and equipment wrappings;

·        unusable cement / grouting mixes; and

·        damaged or contaminated construction material.

6.5.5       The total quantity of C&D material generated during the construction phase will be dependent on the construction methods and site practices adopted, and hence it is difficult to quantify at this stage.  The amount of C&D material expected to be generated will be quantified in the Waste Management Plan to be prepared by the Contractor.  An estimate of the C&D material likely to be generated from new building construction has been made based on the gross floor area (GFA) of the buildings to be constructed (Table 6.3).  The proposed ventilation buildings will be small structures and the volume of C&D material to be generated is likely to be small.

Table 6.3      Estimated Quantities of C&D Material from New Building Construction

Tunnel Building

GFA (m2)

C&D Material (m3)

C&D Material for Off-site Disposal  *

Public Fill (m3)

C&D Waste (m3)

West Ventilation Building





Central Ventilation Building





East Ventilation and Administration Building










Note:   * Forecast ratio for C&D waste : public fill is 2 : 8 (Source : Monitoring of Solid Waste in Hong Kong 1997).

6.5.6       The quantity of C&D material to be produced from the construction of the tunnel buildings has been estimated based on a C&D material generation rate of 0.1 m3 per 1 m2 of GFA constructed ([1]).  A breakdown of the estimated quantities of public fill and C&D waste is also given in Table 6.3.  The C&D material generated from the construction of the tunnel buildings will require off-site disposal.

C&D Material from Demolition Works

6.5.7       Demolition waste will arise from the site clearance of the existing Island Eastern Corridor, the Rumsey Street Flyover downramp and the Hing Fat Street Flyover.  The volume of waste is not expected to be significant and will comprise primarily concrete.  The demolition wastes will be taken either to landfill or, where inert and free from contamination, be reused within the project as far as possible.  The breakdown of the estimated quantities of demolition material is given in Table 6.4.  It is assumed that approximately 95% of the C&D material will be public fill and the other will be C&D waste.

Table 6.4        Estimated Quantities of Demolition Material


Quantity (m3)

Estimated breakdown (m3)

Public Fill

C&D Waste  for Off-site Disposal

Off-site Disposal

Reuse On-site

Existing Island Eastern Corridor





Existing Rumsey Street Flyover





Hing Fat Street Flyover










Note:  The above quantities include superstructures, substructures (exclude piles) and filling materials for abutments.

6.5.8       C&D material should be sorted on-site into public fill (that is, the inert portion), which should be reused on-site wherever possible, and C&D waste (that is, the non-inert portion) which may need to be disposed of to landfill.  As the majority of demolition material will comprise concrete, however, it is anticipated that this public fill material may not be possible for reuse on-site and will require off-site disposal to public filling areas.  The tunnel excavation works undertaken prior to the demolition works will provide large amounts of C&D material which can be reused on-site and thus the surplus demolition material will require off-site disposal due to the limited capacity of the CWB & IECL project to receive material during the late stage of construction works.  It is estimated that around 5% of the public fill will be suitable for reuse on-site; a volume of approximately 1,268 m3, and should be broken down to 250 mm in size.  The surplus public fill with an estimated volume of approximately 24,097 m3 will require off-site disposal.

6.5.9       If surplus public fill is to be transported off-site for disposal in public filling areas, the project initiating office should contact the Secretariat of the Public Fill Committee (Chief Engineer / Port Works, CED) at the detailed design stage to check the availability of such sites.

6.5.10    If construction wastes are generated in large quantities they may hinder building operations and present a safety hazard if not removed, in addition to causing potential water quality impacts, as discussed in Section 5.  The storage and disposal of C&D materials have the potential to create similar visual, dust and associated traffic impacts as the storage and disposal of excavated material.

6.5.11    A summary of the estimated quantity of the C&D material requiring disposal off-site for the whole CWB & IECL project is shown in Table 6.5.

Table 6.5        Summary of the C&D Material requiring disposal off-site arising from the CWB & IECL Project


Construction and Demolition Material

Requiring Disposal Off-site


Type of Fill (m3)

Public Fill

Sand Fill

Excavated Material from

works entrusted  to TDD’s CRIII Project




Excavated Material from

works entrusted to TDD’s WDII Project




Excavated Material from works for

Central Interchange


Tunnel Buildings














C&D Material from

Tunnel Building Construction

Demolition of Existing Structures










Sub total









1.      The quantities and types of excavated material are estimated and based on the current reclamation fill proposals and construction programmes of CRIII, WDII and CWB & IECL Projects.  The actual quantities and types may vary subject to the implementation programmes adopted by contractors during construction.

2.      Part of public fill material from WDII will be excavated from the existing Wanchai Public Cargo Working Area.

3.      Public fill material from the Central Interchange will be excavated from the area between the existing ground level (approx. +5.0mPD) to a level of   +2.6mPD based on the as built drawing of CRI project.

4.      The reuse of surplus material from the Central Interchange and CRIII will be maximised in the WDII Reclamation, however the quantities of these transferred materials should depend on the detailed programme of works that will actually be taken place during construction period.

Excavated Sediment

6.5.12    The construction of the pier foundations for the elevated section of CWB & IECL over the western side of the Causeway Bay Typhoon Shelter will generate excavated marine sediment requiring off-site disposal.  Under the reclamation for Wan Chai Development Phase II sediment will be left in situ at the western corner of the Causeway Bay Typhoon Shelter and thus the piling works for the pier foundations will encounter marine sediment.  The estimated volume of excavated sediment is 730 m3.  The Phase II marine site investigation works for the Wan Chai Development Phase II Comprehensive Feasibility Study included sediment sampling within the western side of the typhoon shelter.  An indication of sediment quality may be made from the sediment testing results for vibrocore MV10 which show that the sediment is classified as Category H (one or more contaminant levels above the Upper Chemical Exceedance Level) in accordance with WBTC No. 3/2000.  The excavated sediment will therefore require confined marine disposal.   Requirements for the transportation and disposal of the excavated sediment are given in Section 6.6.

Chemical Waste

6.5.13    Chemical waste as defined under the Waste Disposal (Chemical Waste) (General) Regulation includes any substance being scrap material, or unwanted substances specified under Schedule 1 of the Regulations.  A complete list of such substances is provided under the Regulations.  Chemical wastes likely to be generated during the construction will for the most part arise from the maintenance of plant and equipment.  These may include, but need not be limited to the following:

·        spent filter cartridges containing heavy metals;

·        scrap batteries or spent acid / alkali from their maintenance;

·        brake clutch linings containing asbestos materials;

·        used hydraulic and lubricating oil;

·        spent mineral oils / cleaning fluids from mechanical machinery; and

·        spent solvents / solutions, which may be halogenated, from equipment cleaning activities.

6.5.14    Chemical wastes pose serious environmental and health and safety hazards if not stored and disposed of in an appropriate manner as outlined in the Chemical Waste Regulations.  These hazards include:

·        toxic effects to workers;

·        adverse impacts on water quality from spills and associated adverse impacts on water sensitive receivers; and

·        fire hazards.

6.5.15    If chemical wastes do arise during the construction, they should be stored, transported and disposed of in accordance with the guidelines detailed in Section 6.6.

General Refuse

6.5.16    The construction works will result in the generation of a variety of general refuse requiring disposal. These wastes may include food wastes and packaging, waste paper, and newspapers and will generally be disposed of to landfill.  Release of general refuse into marine waters should not be permitted as introduction of these wastes is likely to have detrimental effects on water sensitive receivers in the area.

6.5.17    The storage of general refuse has the potential to give rise to a variety of adverse environmental impacts.  These include odour if waste is not collected frequently, windblown litter, water quality impacts if waste enters water bodies, and visual impact.  The site may also attract pests and vermin if the waste storage area is not well maintained and cleaned regularly.  In addition, disposal of wastes, at sites other than approved landfills, can also lead to similar adverse impacts at those sites.

6.6             Recycling, Treatment, Storage and Disposal Options

6.6.1       This section discusses the options for waste management and highlights the methodologies available for waste minimisation.

Construction and Demolition Material

6.6.2       Given the likely inert nature of the excavated material, this material should be reused on‑site wherever possible for the CWB and IECL construction works.  However, although the subsequent construction works may take up part of the excavated material from CWB tunnel works during early stage of construction, the remaining surplus excavated material from site clearance of Island Eastern Corridor and demolition the Hing Fat Street Flyover and Rumsey Street Flyover downramp during the late stage of construction is unlikely to be reused on-site.  The surplus good quality excavated material may be used for other reclamation or development projects that have a material deficit.  The excavated material from reclaimed areas may require dewatering prior to disposal.  To enable excavated material to be used for reclamation purposes, it must be kept separate from other waste material such as wood.

6.6.3       The surplus material could be used at other development sites available for receiving fill materials.  The Marine Fill Committee (MFC) manages a “Fill Management Database” containing fill and surplus data for reclamation and earth-moving projects in Hong Kong.  The database is aimed to facilitate the use of surplus materials and to allow contacts amongst project offices for possible arrangement of delivery of materials.  The availability of the development sites for receiving fill materials is, however, determined by the officer responsible for the project.

6.6.4       A number of measures can be introduced during the construction period relating to a high standard of design and management that will minimise the generation of C&D material.

6.6.5       The design could maximise the use of standard wooden panels in formwork so that the maximum reuse of panels can be achieved.  The need to cut panels could also be minimised.  Alternatives such as the use of steel formwork or plastic facing could be considered to increase the potential for reuse.  It is important that wood wastes are stored separately from other C&D wastes to minimise any contamination that would render the wastes unsuitable for disposal at public filling area.

6.6.6       Careful planning and good site management could be employed to minimise the over ordering or mixing of concrete, mortars and cement grouts.  In addition, proper storage and site practices will minimise the damage or contamination of construction materials.  Used bentonite slurries should be reused on-site as far as possible.  The amount of residual used bentonite slurry requiring disposal is estimated to be about 133,749 m3  (from the Central Interchange: 9,703m3, from the entrusted tunnel works in CRIII area:  48,327m3 and from the entrusted tunnel works in WDII area:  75,720 m3).  The residual bentonite slurry should be mixed with dry excavated material for disposal at the designated public filling facilities.  In accordance with WBTC No. 16/96, this ‘wet soil’ should be free from marine mud, household refuse, plastic, metal, industrial and chemical waste, animal and vegetable matter etc.  As a last resort, the residual bentonite slurry may be disposed of at a marine dumping ground subject to obtaining a marine dumping licence from EPD on a case-by-case basis.

6.6.7       It would be advantageous for the Contractor to recycle as much as possible of the construction waste on‑site in order to reduce the requirement to import additional materials. Recycling would also reduce the collection, transportation and disposal of construction waste and any associated charges by the waste haulier.

6.6.8       On-site measures may be implemented that promote the proper disposal of wastes once off site.  For example, having separate skips for inert (rubble, sand, stone, etc) and non‑inert (wood, organics, etc.) wastes would help ensure that the former are taken to public filling areas, while the latter are properly disposed of at controlled landfills.

6.6.9       In order to minimise the impacts of the demolition works, these wastes must be cleared as quickly as possible after demolition.  The demolition and clearance works should therefore be undertaken simultaneously.

6.6.10    A trip-ticket system should be implemented in contracts for the proper disposal of C&D material at public filling facilities or landfills.

Excavated Sediment

6.6.11    In order to determine the disposal requirements of the excavated sediments, sediment sampling and testing are required to be carried out at the design phase of the Project.  The basic requirements and procedures for sediment disposal are specified under the WBTC No. 3/2000.  The excavated sediments will be loaded onto barges and transported to designated disposal sites depending on their level of contaminants.  As discussed in Section 6.5.17, the marine sediment to be excavated is likely to be classified as Category H (but biological test not required).  In accordance with WBTC No. 3/2000, the contaminated sediment must be effectively isolated from the environment upon final disposal and shall be disposed of at the East Sha Chau Contaminated Mud Pits that is designated for the disposal of contaminated mud in Hong Kong.

Chemical Wastes

6.6.12    Chemical wastes will arise principally as a result of maintenance activities.  It is difficult to quantify the amount of chemical waste that will arise from the construction activities since it will be highly dependant on the Contractor's on‑site maintenance requirements and the number of plant and vehicles utilised.

6.6.13    If chemical wastes do arise from the construction works then appropriate methods should be employed for their storage, collection and disposal.  The Contractor should contact an approved operator to collect the wastes for disposal at the Chemical Waste Treatment Facility, or other licensed facility. 

6.6.14    The Chemical Waste Regulations governing the storage and disposal of chemical wastes must be followed, in order to ensure that there are no unacceptable impacts.  The volumes of chemical waste should be kept to a minimum by separation of waste streams and good management that reduce the potential for contamination.

6.6.15    Containers used for the storage of chemical wastes should be suitable for the substance they are holding, resistant to corrosion and maintained in a good condition.  The containers should be stored safely and securely closed.

6.6.16    Chemical wastes should not be stored in any container with a capacity exceeding 450 litres unless the specifications have been approved by the EPD.  Every container of chemical waste should display a label in English and Chinese in accordance with instructions prescribed in Schedule 2 of the Regulations.

6.6.17    The storage area for any containers should not be used for any purpose except for the storage of chemical wastes and should be fully labelled in accordance with the Regulations.  Chemicals that are incompatible and could cause fire or explosion if they are mixed should be segregated in separate areas.  The storage area should be enclosed on at least three sides by a wall, partition or fence that is at least 2 m in height or the height of the tallest container, whichever is greater. Adequate ventilation and space for the handling of containers should be provided, with the area being kept clean and dry.

6.6.18    Liquid chemical wastes should be stored in an area which has an impermeable floor and retention structure with the 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. When calculating the available retaining capacity, the volume occupied by the containers being stored should be taken into consideration.  Bunded areas should be kept clean and dry, possibly by covering.  If water does collect within the bund, it must be tested before being disposed.  This requirement does not apply to large, approved below ground containers.

General Refuse

6.6.19    General refuse generated on‑site should be stored and collected separately from other construction and chemical wastes.  The Contractor may arrange for the collection and disposal of the refuse by a reputable waste haulier.  The removal of waste from the site should be arranged on a daily or at least on every second day by the Contractor to minimise any potential odour impacts, minimise the presence of pests, vermin and other scavengers and prevent unsightly accumulation of waste.

6.6.1       General refuse should be stored in enclosed bins or compaction units.  Recyclable refuse such as paper, cans and plastic bottles should be separately collected for recycling.  Compaction units assist in reducing the volumes of waste to be transported for disposal.  However, the relatively small volumes of wastes generated during the construction may be insufficient to justify the use of compaction units.  Provided appropriate handling, storage, and disposal procedures and facilities are employed during the construction stage, no unacceptable impacts resulting from waste generation are anticipated to occur.

6.7             Mitigation of Adverse Environmental Impacts

6.7.1       The potential environmental impacts associated with waste arisings from the construction of the CWB & IECL and the recommended handling, transportation and disposal options have been discussed in detail in Section 6.6.  This section outlines appropriate mitigation measures to minimise any impact from these construction waste arisings.  These measures should be incorporated into the contract specifications.

Segregation of Wastes

6.7.2       In order to ensure that all waste is disposed of in an appropriate manner, waste shall be separated by category on‑site by the Contractor.  It is recommended that the waste could be segregated into the following defined categories and shall then be disposed of as follows:

·             inert portion of C&D material, that is, public fill, deemed suitable for reclamation or land formation shall be re-used on site as far as possible and the surplus material disposed of at reclamation or public filling areas;

·             non-inert portion of C&D material, that is, C&D waste, deemed unsuitable for reclamation or land formation shall be disposed of at landfill;

·             chemical waste as defined by Schedule 1 of the Waste Regulations (Chemical) 1992, shall be stored in accordance with approved methods defined in the Regulations and the chemical waste disposed of at the Chemical Waste Treatment Centre located at Tsing Yi;

·             excavated sediment shall be disposed at the East Sha Chau contaminated mud pits in accordance with WBTC No. 3/2000; and

·             general refuse shall be disposed of at landfill.

Waste Minimisation

6.7.3       C&D materials should be recycled or reused wherever possible. The demolition material arising from the site clearance of existing Island Eastern Corridor, the Rumsey Street Flyover downramp and Hing Fat Street Flyover should be broken down to 250 mm in size in order to facilitate reuse and recycling.  Steel reinforcement should be removed from the demolition material prior to disposal and reused or recycled.   The waste management strategy to be employed shall be waste minimisation at source.  Where waste generation is unavoidable then the potential for recycling or reuse shall be explored and opportunities taken.  If wastes cannot be recycled, then the recommended disposal routes shall be followed.

6.7.4       Waste reduction measures shall be introduced at the design stage and carried through the construction activities, wherever possible, by careful purchasing control, reuse of formwork and good site management.

6.7.5       Training and instruction of construction staff shall be given at the site to increase awareness and draw attention to waste management issues and the need to minimise waste generation.  The training requirements shall be included in the site Waste Management Plan.

Storage, Collection and Transport of Waste

6.7.6       Reputable waste hauliers shall be used to collect and transport the wastes to the appropriate disposal points.  The necessary measures to minimise adverse impacts, such as windblown litter and dust from the transportation of these wastes, and impacts on water quality during the storage, handling and transportation of these wastes, shall also be instigated.

6.7.7       It is recommended that:

·        wastes shall be handled and stored in a manner which ensures that they are held securely without loss or leakage thereby minimising the potential for pollution.  Release of these potential pollutants into marine waters during storage and handling shall not be permitted as introduction of polluted waters is likely to have detrimental effects on water quality and water sensitive receivers;

·        only reputable waste hauliers authorised to collect the specific category of waste concerned should be employed;

·        removal of demolition material shall coincide with the demolition work;

·        prior to disposal of C&D waste, it is recommended that wood, steel and other metals shall be separated for re-use and / or recycling to minimise the quantity of waste to be disposed of to landfill;

·        appropriate measures shall be employed to minimise windblown litter and dust during transportation by either covering trucks or transporting wastes in enclosed containers;

·        the necessary waste disposal permits shall be obtained from the appropriate authorities, if they are required, in accordance with the Waste Disposal Ordinance (Cap. 354), Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354) and the Land Ordinance;

·        collection of general refuse shall be carried out frequently, preferably daily;

·        waste shall only be disposed of at licensed sites and the site staff and Contractor shall develop procedures to ensure that illegal disposal of wastes does not occur;

·        waste storage areas shall be well maintained and cleaned regularly;

·        a recording system for the amount of wastes generated, recycled and disposed of off-site during the implementation of the project; and

·        in order to monitor the disposal of public fill and C&D waste at public filling areas and landfills, and to control fly-tipping, a trip-ticket system shall be included as one of the contractual requirements and implemented by the Environmental Team.  An Independent Checker (Environment) should be responsible for auditing the results of the system.

6.7.1       It will be the responsibility of the Contractor to satisfy the appropriate authorities that the contamination levels of the marine sediment to be excavated have been analysed and recorded.  According to the WBTC No. 3/2000, this will involve the submission of a formal Sediment Quality Report to the DEP, at least 3 months prior to the construction contract being tendered. 

6.7.2       During transportation and disposal of the excavated marine sediments, the following measures should be taken to minimise potential impacts on water quality.

·        Bottom opening of barges shall be fitted with tight fitting seals to prevent leakage of material.  Excess material shall be cleaned from the decks and exposed fittings of barges and hopper dredgers before the vessel is moved.

·        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.

6.8             Evaluation of Residual Impacts

6.8.1       With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste arisings, minimal residual impacts are anticipated during the construction of the CWB & IECL.  

6.9             Environmental Audit

6.9.1       It is recommended that the waste arisings generated during the construction activities be audited periodically to determine if wastes are being managed in accordance with approved procedures and the site Waste Management Plan.  The Waste Management Plan prepared by the Contractor has to be submitted to the Engineer for approval on the advice of the EPD.  The audits should look at all aspects of waste management including waste generation, storage, recycling, transport and disposal.  An appropriate audit programme would be to undertake a first audit near the commencement of the construction works, and then to audit quarterly thereafter. 

6.10         Conclusion

6.10.1    Provided that waste arisings from the construction of the CWB & IECL are handled, transported and disposed of using approved methods as described above, and that no solid or liquid wastes enter nearby marine waters, no unacceptable environmental impacts are envisioned.  In most cases, the inert C&D material can be reused within the project or at reclamation or public filling areas, whilst the non-inert C&D material will be disposed of to landfill.

6.10.2    The mitigation measures recommended in this section should be incorporated into contract specifications to ensure that environmental nuisance does not arise from the storage, transport and disposal of various types of waste arisings from the construction of the CWB & IECL.  These recommendations should form the basis of the site Waste Management Plan to be developed by the Contractor at the detailed design stage.


([1])   Reduction of Construction Waste, Final Report (March 1993).  Hong Kong Polytechnic University.