7                                            Waste Management Assessment

7.1                                      Introduction

This section identifies the potential wastes arising from the construction and operation of the Project.  The potential environmental impacts associated with the handling and disposal of waste arising from the Project are assessed in accordance with the criteria presented in Annexes 7 and 15 of the EIAO-TM, which are summarised as follows:

·           Evaluate opportunities for reduce, reuse and recycle of waste;

·           Estimation of the types and quantities of the wastes to be generated; and

·           Assessment of the secondary environmental impacts due to the management of waste with respect to potential hazards, air and odour emissions, noise, wastewater discharges and traffic.

7.2                                      Legislation Requirement and Evaluation Criteria

The following discussion on legislative requirements and evaluation criteria applies to both the construction and operational phases of the Project.  The following legislation covers, or has some bearing upon, the handling, treatment and disposal of wastes in Hong Kong, and will also be considered in the assessment.

 

·      Waste Disposal Ordinance (Cap 354);

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

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

·      Public Health and Municipal Services Ordinance (Cap 132) - Public Cleansing and Prevention of Nuisances Regulation.

7.2.1                                Waste Disposal Ordinance (Cap 354)

The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes, with waste defined as any substance or article, which is abandoned.  Under the WDO, wastes can only be disposed of at a licensed site.  A breach of these regulations can lead to the imposition of a fine and/or a prison sentence.  The WDO also provides for the issuing of licences for the collection and transport of wastes.  Licences are not, however, currently issued for the collection and transport of construction waste or trade waste.

The Waste Disposal (Charges for Disposal of Construction Waste) Regulation defined construction waste as any substance, matters or things that is generated from construction work and abandoned, whether or not it has been processed or stockpiled before being abandoned, but does not include any sludge, screening or matter removed in or generated from any desludging, desilting or dredging works. 

The Construction Waste Disposal Charging Scheme will come into operation on 1 December 2005.  Processing of account applications by the EPD will start on the same day.  Starting from 1 December 2005, main contractor who undertakes construction work under a contract with value of $1 million or above is required to open a billing account solely for the contract.  Application shall be made within 21 days after the contract is awarded.  Failing this will be an offence under the law.

For construction work under a contract with value less than $1 million, such as minor construction or renovation work, any person such as the owner of the premises where the construction work takes place or his/her contractor can open a billing account; the account can also be used for contracts each with value less than $1 million.  The premises owner concerned may also engage a contractor with a valid billing account to make arrangement for disposal of construction waste.

Charging for disposal of construction waste will start on 20 January 2006 and from this day, any person before using waste disposal facilities for disposal of construction waste needs to open an account.

Construction work contracts awarded or tenders of which closed before 1 December 2005 are eligible for exemption from charges. Application for exemption account must be made on or before 22 December 2005.  Depending on the percentage of inert materials in the construction waste, construction waste can be disposed at public fill, sorting facilities, landfills and outlying islands transfer facilities where different disposal cost would be applied.  The scheme encourages reduce, reuse and sorting of construction waste such that the waste producer can minimise their disposal fee.  Table 7.1 summarises the government construction waste disposal facilities, types of waste accepted and disposal cost. 

Table 7.1        Government Waste Disposal Facilities for Construction Waste

Government Waste Disposal Facilities

Type of Construction Waste Accepted

Charge Per Tonne

Public fill reception facilities

Consisting entirely of inert construction waste

$27

Sorting facilities

Containing more than 50% by weight of inert construction waste

$100

Landfills

Containing not more than 50% by weight of inert construction waste

$125

Outlying Islands Transfer Facilities

Containing any percentage of inert construction waste

$125

 

7.2.2                                Waste Disposal (Chemical Waste) (General) Regulation

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 Regulation, if such a substance or chemical occurs in such a form, quantity or concentration so as to cause pollution or constitute a danger to health or risk of pollution to the environment.

A person should not produce, or cause to be produced, chemical wastes unless he is registered with the EPD.  Any person who contravenes this requirement commits an offence and is liable to a fine and imprisonment.  Producers of chemical wastes must treat their wastes, utilising on-site plant licensed by the EPD or have a licensed collector take the wastes to a licensed facility.  For each consignment of wastes, the waste producer, collector and disposer of the wastes must sign all relevant parts of a computerised trip ticket.  The system is designed to allow the transfer of wastes to be traced from cradle-to-grave.

The Regulation prescribes the storage facilities to be provided on site including labelling and warning signs.  To minimise the risks of pollution and danger to human health or life, the waste producer is required to prepare and make available written procedures to be observed in the case of emergencies due to spillage, leakage or accidents arising from the storage of chemical wastes.  He/she must also provide employees with training in such procedures.

7.2.3                                Land (Miscellaneous Provisions) Ordinance (Cap 28)

The inert portion of C&D materials ([1]) (also called public fill) may be taken to public filling areas.  Public filling areas usually form part of land reclamation schemes and are operated by the Civil Engineering and Development Department (CEDD) and others.  The Land (Miscellaneous Provisions) Ordinance requires that individuals or companies who deliver public fill to the public filling areas obtain Dumping Licences.  The licences are issued by the CEDD under delegated authority from the Director of Lands.

Individual licences and windscreen stickers are issued for each vehicle involved.  Under the licence conditions, public filling areas will accept only inert building debris, soil, rock and broken concrete.  There is no size limit on rock and broken concrete, and a small amount of timber mixed with inert material is permissible.  The material should, however, be free from marine mud, household refuse, plastic, metal, industrial and chemical wastes, animal and vegetable matter and any other materials considered unsuitable by the public filling supervisor.

7.2.4                                Public Cleansing and Prevention of Nuisances Regulation

This Regulation provides a further control on the illegal dumping of wastes on unauthorised (unlicensed) sites.  The illegal dumping of wastes can lead to a fine and imprisonment.

7.2.5                                Other Relevant Guidelines

Other 'guideline' documents, which detail how the Contractor should comply with the regulations are as follows:

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

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

·      New Disposal Arrangements for Construction Waste (1992), EPD & CED, Hong Kong Government;

·      Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), EPD, Hong Kong Government;

·      Works Branch Technical Circular (WBTC) No. 32/92, The Use of Tropical Hard Wood on Construction Site; Works Branch, Hong Kong Government;

·      WBTC No. 2/93, Public Dumps. Works Branch, Hong Kong Government;

·      WBTC No. 2/93B, Public Filling Facilities, Works Branch, Hong Kong Government;

·      Waste Reduction Framework Plan, 1998 to 2007, Planning, Environment and Lands Bureau, Government Secretariat, 5 November 1998;

·      WBTC Nos. 25/99, 25/99A and 25/99C, Incorporation of Information on Construction and Demolition Material Management in Public Works Sub-committee Papers; Works Bureau, Hong Kong SAR Government;

·      WBTC No. 12/2000, Fill Management; Works Bureau, Hong Kong SAR Government;

·      ETWBTC No. 33/2002, Management of Construction and Demolition Material Including Rock; Environment, Transport and Works Bureau, Hong Kong SAR Government;

·      ETWBTC No. 15/2003, Waste Management on Construction Sites; Environment, Transport and Works Bureau, Hong Kong SAR Government; and

·      ETWBTC No. 31/2004, Trip Ticket System for Disposal of Construction & Demolition Materials, Environment, Transport and Works Bureau, Hong Kong SAR Government.

 

7.3                                      Expected Waste Arisings

7.3.1                                Construction Phase

During the construction phase, the main activities, which will potentially result in the generation of waste, include site clearance, excavation, track paving, and renovation of the existing vacant village house for office use.  The typical waste types associated with these activities include:

·      Construction and Demolition Materials (C&DM);

·      Chemical waste;

·      Sewage; and

·      General refuse.

7.3.2                                Operational Phase

The following wastes will be generated from the operation of the karting track:

·      Chemical waste;

·      Sewage; and

·      General refuse.

7.4                                      Waste Impact Assessment

7.4.1                                Construction Phase

C&D Materials

The proposed development site is currently dominated by wasteland (see Figure 7.1).  Site clearance will be required before track paving, but no excavation or slope cutting will be involved.  Site clearance waste, which mainly comprised vegetation, will be produced.  The maximum quantity to be generated is expected to be less than 10m3 which should be disposal of to WENT Landfill.  About 20m3 of inert construction materials, including concrete, brick, rubble, sand etc., are currently dumped on site (see Figure 7.2).  These materials will be reused on-site.

An existing vacant village house within the site boundary will be renovated and used as the office of the karting track without any modification of the structure (see Figure 7.3).  A small amount of construction waste (expected to be less than one truck load, ie < 7 m3) consisting of packing materials, plastics, metal, concrete, wood etc will be produced which should be sorted on-site for recycling or disposal of at landfill.  The kart maintenance yard/store rooms are to be built by ISO containers.  No demolition of existing buildings or new building construction works will be required and hence construction waste generation will be minimal.

Figure 7.1       Current Site Condition

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 7.2       Construction Material Dumped Onsite

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 7.3       Existing Vacant Village House

 

 

 

 

 

 

 

 

 

The 900 m long and 8 m wide karting track will be paved by asphaltic concrete and an area of 3,500 m2 of the site will be paved by concrete.  It is estimated that not more than 20m3 of inert construction waste (or public fill) will be generated.  The public fill should be transported to public filling facilities (ie the Tuen Mun Area 38 Public Fill) for reuse. 

In view of the relative small scale of the Project and the nature of construction activities, potential environmental (ie noise, dust, and water quality) and traffic impacts arising from handling and disposal of the C&D materials will be minimal provided that good construction site practices and mitigation measures recommended in Section 7.5 are properly implemented. 

Chemical Wastes

Chemical waste, as defined under the Waste Disposal (Chemical Waste) (General) Regulation, includes any unwanted substances specified under Schedule 1 of the Regulation.  Substances likely to be generated from the construction of the karting track may include:

 

·      Residual paint from building renovation; and

·      Used lubricant oil from construction plants.

Chemical wastes may pose environmental, health and safety hazards if not stored and disposed of in an appropriate manner as outlined in the Waste Disposal (Chemical Waste) (General) Regulation and the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes.  These hazards may include:

·      Toxic effects to workers;

·      Adverse effects on air, water and land from spills; and

·      Fire hazards.

It is not possible to quantify the amount of chemical waste which will arise from the construction activities since it will be highly dependent on the Contractor’s on-site operation and maintenance requirements.  In the view of the small scale of the Project, it is expected that the amount of chemical waste (eg left over paints and used lubricant oil) to be generated will be in the order of a few litres.  With the incorporation of suitable arrangements for the storage, handling, transportation and disposal of chemical wastes under the requirements stated in the Code of Practice on the Packaging, Labelling and Storage of Chemical Waste, no adverse environmental and health impacts will result from the handling, transportation and disposal of a small quantity of chemical waste arising from the Project.

Sewage

Sewage will arise from the construction workforce and night soil from chemical toilets.  If not properly managed, these materials could cause odour and potential health risks to the workforce by attracting pests and other disease vectors.

An adequate number of portable toilets will be provided at the site to ensure that sewage from site staff is properly collected.  No adverse environmental impacts are envisaged provided that the portable toilets are properly maintained by a licensed contractor and the collected sewage is disposed at the designated Sewage Treatment Works (eg Pillar Point Sewage Treatment Works).

General Refuse

The presence of a construction site with workers and associated site office will result in the generation of a variety of general refuse requiring disposal.  General refuse will mainly consist of food waste, aluminium cans and waste paper.

The storage of general refuse has the potential to give rise to adverse environmental impacts.  These include odour if the waste is not collected frequently (for example, daily), windblown litter, water quality impacts if waste enters water bodies, and visual impact.  The site may also attract pests, vermin, and other disease vectors if the waste storage areas are not well maintained and cleaned regularly.  In addition, disposal of wastes at sites other than licensed landfills, can also lead to similar adverse impacts at those sites.

It is estimated that a maximum of about 30 workers will be working at the site at any one time.  The amount of general refuse to be generated will be about 19.2 kg per day.  Recyclable materials (ie paper, plastic bottle and aluminium can) should be separated and disposed of at the recycling bins (ie the Government 3 bins recycling programme) in order to minimise the amount of general refuse to be disposed of at landfill.  Provided that the mitigation measures recommended in Section 7.5.4 are adopted, the environmental impacts caused by the storage, handling, transport and disposal of general refuse are expected to be negligible. 

The potential traffic associated with the off-site disposal of construction waste, chemical waste, sewage and general refuse will be less than 4 vehicles per day.  It is not anticipated that it will cause adverse traffic impact to the local road network.

7.4.2                                Operational Phase

Chemical Waste

No major maintenance works will be conducted on-site.  Karts operation will be the primary source of chemical waste which may include lubricants, chain oil, and brake cleaner.  From the past experience of HKKC and the number of karts operated on-site, the quantity of chemical waste to be generated will be in the order of 3 m3 per month.   Provided that the handling, storage and disposal of chemical wastes are in accordance with the Code of Practice on the Packaging, Labelling and Storage of Chemical Waste, adverse environmental impacts would not be expected.  Detailed mitigation and control requirements are listed in Section 7.5. 

Sewage

Sewage will arise from the operation staff and visitors.  4 mobile toilets would be provided for the use of staff and visitors to ensure that all sewage are properly collected.  It is anticipated that about 20 of staff and maximum 200 visitors will use the site per day.  The maximum quantity of sewage to be generated will be about 6.2 m3 per day.  No adverse environmental impacts are envisaged provided that the portable toilets are properly maintained by a licensed contractor and the collected sewage is disposed at the designated Sewage Treatment Works.

General Refuse

General refuse will arise from the operation staff and visitors.  General refuse may consist of food waste, plastic, aluminium can and waste paper.  Based on the number of staff and visitor using the site, it is estimated that maximum 140 kg of general refuse will be generated per day.  Recyclable materials (ie paper, plastic bottle and aluminium can) should be separated and disposed of at the recycling bins (ie the Government 3 bins recycling programme) in order to minimise the amount of general refuse to be disposed of at landfill.   The non-recyclable general refuse should be disposed of at the nearest refuse collection point on a daily basis.  With respect to the small quantity of general refuse to be disposed of, no adverse environmental impact associated with the handling and disposal of the refuse is anticipated. 

The potential traffic associated with the off-site disposal of chemical waste, sewage and general refuse will be less than 3 vehicles per day.  It is not anticipated that it will cause adverse traffic impact to the local road network.

7.5                                      Mitigation Measures

This section recommends the mitigation measures or good practices to avoid or minimize potential adverse environmental impacts associated with handling, collection and disposal of waste arising from the construction and operation of the proposed karting track.     

It is the Contractor’s responsibility to ensure that only reputable licensed waste collectors are used and that appropriate measures to minimize adverse impacts, including windblown litter and dust from the transportation of these wastes, are employed.  In addition, the Contractor must ensure that all the necessary waste disposal permits are obtained for the construction and operational phases.

7.5.1                                C&D Materials

Wherever practicable, inert materials should be segregated from other wastes to avoid contamination thereby ensuring acceptability at public filling areas and avoiding the need for disposal at landfill.

Measures taken in the Planning Design Stages to Reduce the Generation of C&DM

The various waste management options can be categorized in terms of preference from an environmental viewpoint.  The options considered to be more preferable have the least impacts and are more sustainable in the long term.  Hence, the waste management hierarchy is as follows:

·      Avoidance and minimization, that is, reduction of waste generation through changing or improving practices and design;

·      Reuse of materials, thus avoiding disposal (generally with only limited reprocessing);

·      Recovery and recycling, thus avoiding disposal (although reprocessing may be required); and

·      Treatment and disposal, according to relevant law, regulations, guidelines and good practice.

This hierarchy should be used to evaluate the waste management options, thus allowing maximum waste reduction and often reduced disposal costs.  Records of quantities of wastes generated, recycled and disposed (locations) shall be kept.

Recommended Construction Phase Measures for the Reduction of C&DM Generation

The Contractor should recycle as much of the C&DM as possible on-site.  Public fill and construction waste should be segregated and stored in different containers or skips to facilitate reuse or recycling of materials and their proper disposal.  Surplus public fill should be delivered to the adjacent Tuen Mun Area 38 Fill Bank or Tuen Mun Area 38 Temporary Construction Waste Sorting Facility for proper reuse while the construction waste should be delivered to the WENT Landfill.    

7.5.2                                Chemical Waste

The Contractor for the construction works and the operator of the karting track should be registered with the EPD.  Chemical waste should be handled in accordance with the Code of Practice on the Packaging, Handling and Storage of Chemical Wastes as follows.  Containers used for storage of chemical wastes should:

·     be suitable for the substance they are holding, resistant to corrosion, maintained in a good condition, and securely closed;

·     have a capacity of less than 450 L unless the specifications have been approved by the EPD; and

·     display a label in English and Chinese in accordance with instructions prescribed in Schedule 2 of the Regulations.

The storage area for chemical wastes should:

·     be clearly labelled and used solely for the storage of chemical waste;

·     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 entering (water collected within the bund must be tested and disposed of as chemical waste, if necessary); and

·     be arranged so that incompatible materials are appropriately separated.

Disposal of chemical waste should be:

·     via a licensed waste collector; and

·     to a facility licensed to receive chemical waste, such as the Chemical Waste Treatment Facility which also offers a chemical waste collection service and can supply the necessary storage containers.

7.5.3                                Sewage

An adequate number of portable toilets should be provided for the on-site construction workforce.  4 mobile toilets would be provided for the use of visitors during operational phase.  All portable toilets should be maintained in a state that will not deter the users from using them.  Night soil should be regularly collected by a licensed collector for disposal at the Pillar Point Sewage Treatment Works.

7.5.4                                General Refuse

General refuse should be stored in enclosed bins separately from construction and chemical wastes.  Recyclables (ie paper and aluminium can and plastic bottles) should be stored separately to facilitate subsequent recycling.  A reputable waste collector should be employed by the Contractor to remove general refuse from the site, separately from construction and chemical wastes, on a daily basis to minimise odour, pest and litter impacts.  The burning of refuse on construction sites is prohibited by law.

7.5.5                                Management of Waste Disposal

The contractor should open a billing account with EPD in accordance with the Waste Disposal (Charges for Disposal of Construction Waste) Regulation for the payment of disposal charges.  Every waste load transferred to government waste disposal facilities such as public fill, sorting facilities, landfills or transfer station would required a valid “chit” which contain the information of the account holder to facilitate waste transaction recording and billing to the waste producer.  A trip-ticket system should also be established in accordance with Works Bureau Technical Circular No.31/2004 to monitor the disposal of solid wastes at transfer station/landfills, and to control fly-tipping.  The billing “chit” and trip-ticket system will be included as one of the contractual requirements and implemented by the contractor.

A recording system for the amount of waste generated, recycled and disposed of (including the disposal sites) should be established during the construction stage.

7.5.6                                Staff Training

Training should be provided to workers on the concepts of site cleanliness and on appropriate waste management procedures, including waste reduction, reuse and recycling at the beginning of the Contract.

7.6                                      Residual Environmental Impacts

With the implementation of the recommended mitigation measures, minimal residual impacts are anticipated from the construction and operation of the karting track.

7.7                                      Conclusions

The anticipated quantities of C&D materials to be generated from site clearance and building renovation, and chemical wastes, sewage and general refuse to be generated during both the construction and operational phases will be minimal.  With the implementation of the recommendations in Section 7.5, the storage, handling, collection, transport and disposal of C&D materials, chemical waste, sewage and general refuse will not cause adverse environmental impact with respect to the criteria specified in the EIAO-TM and traffic impact to local road network.

 


([1])           “C&D materials” refers to materials arising from any land excavation or formation, civil/building construction, road works, building renovation or demolition activities.  It includes various types of reusable materials, building debris, rubble, earth, concrete, timber and mixed site clearance materials. When sorted properly, materials suitable for land reclamation and site formation (known as public fill) should be reused at public filling area.  The rock and concrete can be crushed and processed to produce aggregates for various civil and building engineering applications.  The remaining C&D waste (comprising timber, paper, plastics, general refuse) are to be disposed of at landfills.