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Contents |
Chapter Title
Tables
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Table 7.1:__ Summary of Waste Arising during Construction Phase Table 7.2:__ Estimation of General Refuse Generation during Operation Phase
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7
Waste
Management Implications
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This section identifies the potential waste arising from the construction and operation activities of the Project and evaluates the potential environmental impacts that may result from waste generated. Mitigation measures and good site practices, including waste handling, storage and disposal, are recommended with reference to applicable waste legislation and management guidelines to minimise potential waste management impacts.
The criteria and guidelines for assessing waste management implications are outlined respectively in Annexes 7 and 15 of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM).
The following legislation relates to the handling, treatment and disposal of wastes in Hong Kong and has been used in assessing potential impacts:
¡ Waste Disposal Ordinance (Cap. 354)
¡ Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354C)
¡ Waste Disposal (Charges for Disposal of Construction Waste) Regulation (Cap. 354N)
¡ Public Health and Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention of Nuisances Regulation
¡ Land (Miscellaneous Provisions) Ordinance (Cap. 28)
The Waste Disposal Ordinance (WDO) prohibits the unauthorised disposal of wastes. Construction waste is defined as any substance, matter or thing 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, screenings or matter removed in or generated from any desludging, desilting or dredging works. Under the WDO, wastes can be disposed of only at designated waste disposal facilities.
Under the WDO, the Chemical Waste (General) Regulation provides regulations for chemical waste control, and administers the possession, storage, collection, transport and disposal of chemical wastes.
According to the Waste Disposal (Chemical Waste) (General) Regulation, all producers of chemical waste must register with Environmental Protection Department (EPD) and treat their wastes, either utilising on-site plant licensed by 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.
The EPD has also issued a ‘guideline’ document, the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes (1992), which details how the Contractor should comply with the regulations on chemical wastes.
Under the Waste Disposal (Charges for Disposal of Construction Waste) Regulation, enacted in January 2006, construction waste delivered to a landfill for disposal must not contain more than 50% by weight of inert material. Construction waste delivered to a sorting facility for disposal must contain more than 50% by weight of inert material, and construction waste delivered to a public fill reception facility for disposal must consist entirely of inert material.
The Public Cleansing and Prevention of Nuisances Regulation provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.
The Land (Miscellaneous Provisions) Ordinance requires that dumping licenses be obtained by individuals or companies who deliver public fill to public filling areas. The CEDD issues the licences under delegated powers from the Director of Lands. The current policy related to dumping of C&D materials is documented in the Works Branch Technical Circular No. 2/93 – Public Dumps. C&D materials that are wholly inert, namely public fill, should not be disposed of to landfill, but taken to fill banks or public filling areas.
Individual licences and windscreen stickers are issued for each vehicle involved. Under the licence conditions, public fill reception facilities will only accept soil, sand, rubble, brick, tile, rock, boulder, concrete, asphalt, masonry or used bentonite. In addition, in accordance with paragraph 12 of the Development Bureau (DEVB) Technical Circular (Works) TC(W) No.6/2010, Public Fill Committee (PFC) will advise on the acceptance criteria. The material will, 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 fill reception facility supervisor.
The criteria for assessing waste management implications are outlined in Annex 7 of the EIAO-TM. The methods for assessing potential waste management impacts during construction and operation phases of the Project follow those presented in Annex 15 of the EIAO-TM and include the following:
¡ Identify the quantity, quality and timing of waste arising as a result of the construction and operation activities of the Project;
¡ Adopt appropriate design, general layout, construction methods and programme to minimise the generation of inert C&D materials and maximise the use of inert C&D materials for other construction works.
¡ Prior to considering the disposal options for various types of wastes, opportunities for reducing waste generation, on-site or off-site reuse and recycling should be fully evaluated.
¡ Estimate the types and quantities of the wastes required to be disposed of.
¡ Identify the disposal methods / options for each type of waste.
¡ Identify the transportation routings and the frequency of the trucks / vessels involved.
¡ Assess the potential impacts from the management of solid waste with respect to potential hazards, air and odour emissions, noise, wastewater discharges, ecology and public transport.
The activities to be carried out for construction of the Project would generate a variety of wastes that can be divided into different key categories based on their composition and ultimate method of disposal. The identified waste types include:
¡ Construction and demolition (C&D) materials;
¡ Chemical waste; and
¡ General refuse.
Each type of the above waste arising is described below, together with an evaluation of the potential environmental impacts associated with the waste generation, handling, storage, transport and disposal.
Key Sources of C&D Materials
It is anticipated that the majority of C&D materials will be generated from the following key construction activities:
¡ Site clearance;
¡ Site formation works;
¡ Foundation works;
¡ Retaining walls and slope works;
¡ Building construction and superstructure works; and
¡ Improvement of existing Kong Nga Po Road.
The excavation, foundation, site clearance and site formation works will be the major source of C&D materials generated by the Project. It is estimated that the total amount of C&D materials to be generated would be approximately 603,000 m3, in which about 120,000 m3 would be rock, and about 480,000 m3 would be soil and the remaining 3,000 m3 would be non-inert C&D materials. The C&D materials is mainly generated from excavation, foundation, site clearance and site formation in year 2018 to 2022.
On-site Reuse of Inert C&D Materials as Fill Materials
The inert materials should be segregated from the C&D materials on-site for reuse as far as practicable. In order to minimise the impact resulting from collection and transportation of C&D materials for off-site disposal, the inert C&D materials that could be reused on-site as fill materials as far as practicable. It is estimated that the Project would require a total of 219,000 m3 of fill materials for construction phase.
Off-site Reuse or Disposal of Surplus C&D Materials
The surplus inert C&D materials generated will be about 381,000 m3, which could be reused by other projects in Hong Kong. During the detailed design stage, further alternative disposal arrangement (e.g. other potential projects that could receive inert C&D materials from the Project) shall be continuously explored and identified. If no potential projects could receive the surplus inert C&D materials, the remaining inert C&D materials could be disposed of at the Government's Public Fill Reception Facilities (PFRFs) for beneficial use by any other projects in Hong Kong. Liaison with the CEDD Public Fill Committee (PFC) on the management of inert C&D materials will be required before the commencement of construction work. According to the Project Administration Handbook for Civil Engineering Works (2014 Edition) - Chapter 4, Section 4.1.3, the project office is required to draw up a Construction and Demolition Material Management Plan (C&DMMP) at the feasibility study or preliminary design stage to PFC for approval for each project, which generates more than 50,000 m3 of C&D material including rock or that requiring imported fill in excess of 50,000 m3. No construction work is allowed to proceed until all issues on management of C&D materials have been resolved and all relevant arrangements have been endorsed by the relevant authorities including PFC and EPD.
It is estimated that around 125 vehicle-trips per day would be needed for off-site delivery of the surplus inert C&D materials by dump trucks (each with a minimum loading capacity of about 6 m3) via Kong Nga Po Road.
The Contractor should separate the non-inert C&D materials from the inert C&D materials on-site. Any recyclable materials (e.g., metal) should be segregated from the non-inert C&D materials for collection by reputable licensed recyclers. The remaining non-recyclable waste materials will be disposed of at designated landfill sites by a reputable licensed waste collector.
The non-inert C&D materials (with the recyclable materials segregated for recycling) will be delivered to designated landfill sites by dump trucks via Kong Nga Po Road. With a loading capacity of about 6 m3 per dump truck, it can be estimated that up to about 5 vehicle-trips per day would be required for delivery of the non-inert C&D materials, which would not impose significant traffic loading on Kong Nga Po Road. The storage, handling, transport and disposal of non-inert C&D materials, if not managed properly, would have the potential to create visual, dust and water quality impacts.
With careful planning for reuse of C&D materials on-site and proper implementation of good construction site practice and mitigation measures recommended, potential dust, noise and water quality impacts associated with on-site handling and transportation of C&D materials are not anticipated.
Chemical wastes arising during the construction phase may pose environmental, health and safety hazards if not stored and disposed of in an appropriate manner as stipulated in the Waste Disposal (Chemical Waste) (General) Regulations. The potential hazards include:
¡ Toxic effects to workers;
¡ Adverse impacts on water quality from spills; and
¡ Fire hazards.
The maintenance and servicing of construction plant and equipment may generate some chemical wastes such as used solvents, contaminated rags and waste lubricating oil. It is difficult to quantify the amount of chemical waste that will arise from the construction activities since it will be dependent on the Contractor’s on-site maintenance requirements and the amount of plant utilised. However, it is anticipated that the quantity of chemical waste, such as waste lubricating oil and solvents produced from plant maintenance, will be small and in the order of few hundred litres per month. The amount of chemical waste to be generated will be quantified in the Waste Management Plan to be prepared by the Contractor for the site.
Materials classified as chemical wastes will require special handling and storage arrangements before removal for off-site disposal at the approved Chemical Waste Treatment Facility or recycling by licensed facilities. Mitigation and control requirements for chemical wastes are detailed in Section 7.5.1.4. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts are not expected.
The construction workforce will generate refuse comprising food scraps, waste paper and empty containers etc. Such refuse will be properly managed so that intentional or accidental release to the surrounding environment will be avoided. Disposal of refuse at sites other than approved waste transfer or disposal facilities will be prohibited. Effective collection of site wastes will be required to prevent waste materials being blown around by wind, flushed or leached into the marine environment, or creating an odour nuisance or pest/ vermin problem. Waste storage areas will be well maintained and cleaned regularly. The daily arising of general refuse from the construction workforce can be estimated based on a generation rate of 0.65kg per worker per day.
The maximum number of construction workers to be employed will be 400 workers per day. Based on a generation rate of 0.65kg per worker per day, the maximum daily arising of general refuse during the construction period would be approximately 260kg and this waste can be effectively controlled by normal measures. Corresponding to this maximum daily volume, up to around 1 vehicle-trip per day would be needed for delivery of the general refuse by dump trucks (each with a loading capacity of about 6 m3) to the designated landfill sites via Kong Nga Po Road. Given this small daily number of vehicle-trips, the extra traffic loading on Kong Nga Po Road would be negligible.
With the implementation of good waste management practices at the site as detailed in Section 7.5.1.5, adverse environmental impacts are not expected to arise from the storage, handling and transportation of the general refuse from construction workforce.
Table 7.1 presents a summary of all key types of waste arising during the construction phase of the Project.
Table 7.1: Summary of Waste Arising during Construction Phase
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Waste Type |
Key Sources of Waste Generation |
Timing of Waste Generation |
Estimated Quantity of Waste Generation |
Waste Reuse or Disposal |
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Inert C&D Materials |
Site clearance; site formation; foundation; retaining walls and slope works; building construction and superstructure works; road improvement works |
Tentatively from 2018 to 2022 |
About 600,000 m3 in total |
About 219,000 m3 of the inert C&D materials generated would be reused on-site as fill materials. The remaining 381,000 m3 would be delivered off-site to any identified projects that would need fill materials and/or to the government’s PFRF for beneficial use by other projects in Hong Kong |
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Non-inert C&D Materials |
Site clearance; site formation; foundation; retaining walls and slope works; building construction and superstructure works; road improvement works |
Tentatively from 2018 to 2022 |
About 3,000 m3 in total |
The non-inert C&D materials will be disposal of at landfills after on-site sorting and segregation of recyclable materials |
|
General Refuse |
Food scarps, waste paper, empty containers, etc. generated from the site workforce |
Tentatively from 2018 to 2022 |
0.65kg per worker per day, the maximum daily arising of general refuse during the construction period would be approximately 260kg
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Encourage segregation of recyclable materials (e.g., paper, tin-cans, etc.) for collection by outside recyclers Refuse station for compaction and containerisation and then to landfill for disposal |
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Chemical Waste |
Used cleansing fluids, solvents, lubricating oil, waste fuel, etc., from maintenance and servicing of construction plant and equipment |
Tentatively from 2018 to 2022 |
Anticipated as small quantity and in the order of few hundred litres per month To be quantified in the site Waste Management Plan to be prepared by the Contractor |
Disposal at the Chemical Waste Treatment Centre or other licensed recycling facilities |
The Project is anticipated to involve the following waste generating activities during operation phase:
¡ Firing training activities;
¡ Weapons training activities; and
¡ Driving training activities.
The following types of wastes would be generated from abovementioned activities:
¡ General refuse;
¡ Chemical waste; and
¡ Cartridge casings
Each type of the above waste arising is discussed below:
General refuse (such as food scraps, waste paper, empty containers and packaging, etc.) from operation of the Project will mainly be generated from training activities and canteens within the Project site. Such refuse will be properly managed by suitable waste collectors so that intentional or accidental release to the surrounding environment will not occur.
The amounts of general refuse generation during the operation phase have been preliminarily estimated based on the population intake estimates prepared for the Development Plan of the Project, and are summarised in Table 7.2.
Table 7.2: Estimation of General Refuse Generation during Operation Phase
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Item |
Population intake estimate |
Waste classification(1) |
Per capita disposal rate(2) |
Estimated Waste Generation |
|
Total No. of Trainees |
344 |
Commercial waste |
0.35kg/ person/ day* |
120kg/day |
|
Total Employment Population |
192 |
Commercial waste |
0.35kg/ person/ day* |
67kg/day |
Source: (1) Appendix 1: Classification of Solid Waste and Monitoring Methodology, in Monitoring of Solid Waste in Hong Kong – Waste Statistic for 2014
(2) Plate 2.1 and Plate 2.7, in Monitoring of Solid Waste in Hong Kong – Waste Statistic for 2014
Note: *Calculated from percentage of commercial waste over total municipal solid waste, based on municipal solid waste disposal rate
Corresponding to this waste volume and with a loading capacity of about 12 tons per refuse collection vehicle (RCV), it can be estimated that up to around 1 vehicle-trip per day would be needed for delivery of the general refuse by RCV to the designated landfill sites, which will be via Kong Nga Po Road. Given this small daily number of vehicle-trips, the extra traffic loading on Kong Nga Po Road would be negligible.
Storage of general refuse would generate odour nuisance and visual impact if they are not managed in a proper manner. Vermin and pests may also be attracted if the waste containers are not cleaned or maintained properly and frequently. Therefore, the general refuse should be temporarily stored in proper containers with covers to avoid adverse impact to the surroundings. To reduce waste and improve recycling, it is expected that waste such as waste paper, plastics and aluminium can be segregated for off-site recycling. A reputable licensed waste collector should be employed to collect the general refuse daily for disposal at designated landfill sites. With proper implementation of waste management practices, the environmental impact from handling and disposal of general refuse would not be anticipated.
Chemical waste will be generated from maintenance activities for some firing range structures and petrol and diesel filling activities for the vehicle fleet at Police Driving and Traffic Training Facilities (PD&TTF). Chemical waste such as waste paint, used solvents and spent chemicals are expected to be generated from these activities. It is difficult to quantify the amount of chemical waste that will arise from those activities at this stage since it will be dependent on the equipment maintenance requirements and the amount of equipment utilised.
Mobile oil refuelling truck for refuelling of helicopters will be required under some specific operational need upon request. The truck will temporarily park near the helipad and wait for the helicopter to arrive. The refuelling operation will be carried out at the helipad. Given that the refuelling activities will only be required on an as-needed basis, generation of chemical waste during the refuelling activities would not be anticipated.
Chemical wastes arising during the operation phase may pose environmental, health and safety hazards if not stored and disposed of in an appropriate manner as stipulated in the Waste Disposal (Chemical Waste) (General) Regulations. The potential hazards include:
¡ Toxic effects to workers;
¡ Adverse impacts on water quality and wildlife from spills; and
¡ Fire hazards.
Chemical wastes will require special handling and storage arrangements in accordance with the relevant regulations before off-site disposal at the approved Chemical Waste Treatment Facility or recycling by licensed facilities. Mitigation and control requirements for chemical wastes are detailed in Section 7.5.2.2. Provided that the handling, storage and disposal of chemical wastes will be in accordance with these requirements, adverse environmental impacts will not be expected.
Cartridge casings and bullet heads will be generated from firing and training activities. It is estimated that approximately 7,000kg of cartridge casings and bullet heads will be generated per year. The cartridge casings and bullet heads will be kept in storeroom and collected by designated contractor. With proper implementation of waste management practices, the environmental impact from handling and disposal of cartridge casings and bullet heads would not be anticipated.
¡ Nomination of an approved person, such as a site manager, to be responsible for good site practices, arrangements for collection and effective disposal to an appropriate facility, of all wastes generated at the site
¡ Training of site personnel in proper waste management and chemical handling procedures
¡ Provision of sufficient waste disposal points and regular collection of waste
¡ Appropriate measures to minimise windblown litter and dust/odour during transportation of waste by either covering trucks or by transporting wastes in enclosed containers
¡ Stockpiles of C&D materials should be kept covered by impervious sheets to avoid wind-blown dust.
¡ All dusty materials including C&D materials should be sprayed with water immediately prior to any loading transfer operation so as to keep the dusty material wet during material handling at the stockpile areas
¡ Provision of wheel washing facilities before the trucks leaving the works area so as to minimise dust introduction to public roads
¡ Well planned delivery programme for off-site disposal such that adverse environmental impact from transporting the inert or non-inert C&D materials is not anticipated
Good management and control can prevent the generation of a significant amount of waste. Waste reduction is best achieved at the planning and design stage, as well as by ensuring the implementation of good site practices. Recommendations to achieve waste reduction include:
¡ Sort non-inert C&D materials to recover any recyclable portions
¡ Segregation and storage of different types of waste in different containers or skips or stockpiles to enhance reuse or recycling of materials and their proper disposal
¡ Encourage collection of recyclable waste such as waste paper and aluminium cans by providing separate labelled bins to enable such waste to be segregated from other general refuse generated by the work force
¡ Proper site practices to minimise the potential for damage or contamination of inert C&D materials
¡ Plan the use of construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste
In addition to the above measures, specific mitigation measures are recommended below for the identified waste arising to minimise environmental impacts during handling, transportation and disposal of these wastes.
In order to minimise impacts resulting from collection and transportation of inert C&D materials for off-site disposal, the inert C&D materials should be reused on-site as fill material as far as practicable. In addition, inert C&D materials generated from excavation works could be reused as fill materials in local projects that require public fill for reclamation.
The surplus inert C&D materials will be disposed of at the Government’s PFRFs for beneficial use by other projects in Hong Kong.
The C&D materials generated from general site clearance should be sorted on site to segregate any inert materials for reuse or disposal at PFRFs whereas the non-inert materials will be disposed of at the designated landfill site.
In order to monitor the disposal of inert and non-inert C&D materials at respectively PFRFs and the designated landfill site, and to control fly-tipping, it is recommended that the Contractor should follow the DEVB Technical Circular (Works) No. 6/2010 for Trip Ticket System for Disposal of Construction & Demolition Materials issued by Development Bureau. In addition, it is also recommended that the Contractor should prepare and implement a Waste Management Plan detailing their various waste arising and waste management practices in accordance with the relevant requirements of the ETWB Technical Circular (Works) No. 19/2005 Environmental Management on Construction Site.
General refuse should be collected on a daily basis and delivered to the refuse collection point accordingly. A reputable waste collector should be employed to remove general refuse regularly to avoid odour nuisance or pest/vermin problem. Sufficient recycling containers are recommended to be provided at suitable locations of the Project to encourage recycling of waste such as aluminium cans, plastics and waste paper.
All cartridge casings and bullet heads should be collected from the firing range daily and kept in the storeroom for disposal. A designated waste contractor should be employed to remove cartridge casings and bullet heads regularly.
With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste arising, residual impacts are not anticipated during both construction and operation phases of the Project.
It would be the Contractor’s responsibility to ensure that all wastes produced during the construction phase of the Project are handled, stored and disposed of in accordance with good waste management practices and the relevant regulations and requirement. The recommended mitigation measures should form the basis of the Waste Management Plan (WMP) to be developed by the Contractor throughout the construction period. The WMP shall be prepared and implemented in accordance with ETWB TC (W) No. 19/2005 Environmental Management on Construction Site.
Throughout the construction phase of the Project, regular site inspections as part of the Environmental Monitoring and Audit (EM&A) procedures should be carried out to determine if wastes are being managed in accordance with approved procedures and the WMP. Different aspects of waste management including waste generation, storage, recycling, treatment, transport and disposal would be included in the programme.
With the implementation of the recommended mitigation measures for handling, transportation and disposal of the identified waste arisings, no adverse impacts are anticipated during operation phase of the Project. Therefore, no specific waste monitoring during operation phase is required.
The major waste types generated by the construction activities will include C&D materials from site clearance, site formation works, foundation works, retaining walls and slope works, building construction and superstructure works, and road improvement works; chemical waste from maintenance and servicing of construction plant and equipment and general refuse from the workforce. Provided that all these identified wastes are handled, transported and disposed of in strict accordance with the relevant legislative and recommended requirements and that the recommended good site practices and mitigation measures are properly implemented, no adverse environmental impact is expected during the construction phase.
During the operation phase, the key waste types generated will include general refuse from staff and trainees within Project; chemical waste from regular maintenance activities for some firing range structures and petrol and diesel filling activities for police vehicle fleet; as well as cartridge casings and bullet heads from firing and training activities. Provided that all these wastes are handled, transported and disposed of in strict accordance with the relevant legislative requirements and the recommended mitigation measures are properly implemented, no adverse environmental impact is expected during the operation phase.