6 WASTE MANAGEMENT

6.1 Introduction

6.1.1 This section includes the discussion of the following issues in relation to waste management:

• identifies the type of wastes that would be generated during construction and operation phase of the Project;

• assesses the potential environmental impacts that are associated with the handling and disposal of these wastes.

• mitigation measures and good site practice, including waste handling, storage and disposal, were recommended with reference to the applicable legislation and guidelines.

6.1.2 The operation phase of the improved TMRTCS would generate wastes from roadside littering and road maintenance activities. The amount would however be very minimal. The potential environmental impacts arising from the handling and disposal of the small quantity of waste is negligible and therefore would not be evaluated in this report.

6.2 Environmental Legislation, Policies, Plans and Standards

6.2.1 The criteria and guidelines for assessing waste management implications are set out in 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 has been used in assessing potential environmental impacts:

Ÿ Waste Disposal Ordinance (Cap. 354)

Ÿ Waste Disposal (Chemical Waste) (General) Regulation (Cap. 354)

Ÿ Land (Miscellaneous Provisions) Ordinance (Cap. 28)

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

Waste Management

6.2.3 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.

6.2.4 Under the WDO, the Chemical Waste (General) Regulation 1992 provides regulations for chemical waste control, and administers the possession, storage, collection, transport and disposal of chemical wastes. The Environmental Protection Department (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.

6.2.5 The Public Cleansing and Prevention of Nuisances Regulation provides control on illegal tipping of wastes on unauthorised (unlicensed) sites.

Construction and Demolition (C&D) Material

6.2.6 The current policy related to the disposal of C&D material is documented in the Works Branch Technical Circular No. 2/93, ‘Public Dumps’. 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 be obtained by individuals or companies who deliver public fill to public filling areas. The Civil Engineering & Development Department (CEDD) issues the licences under delegated powers from the Director of Lands.

6.2.7 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.

6.2.8 Measures have been introduced under Environment, Transport and Works Bureau (ETWB) TCW No. 33/2002, “Management of Construction and Demolition Material Including Rock” to enhance the management of construction and demolition material, and to minimize its generation at source. The enhancement measures include: (i) drawing up a Construction and Demolition Material Management Plan (C&DMMP) at the feasibility study or preliminary design stage to minimize C&D material generation and encourage proper management of such material; (ii) vetting of the C&DMMP prior to upgrading of the project to Category A in the Public Works Programme; and (iii) providing the contractor with information from the C&DMMP in order to facilitate him in the preparation of the Waste Management Plan (WMP) and to minimize C&D material generation during construction. Projects generating C&D material less than 50,000m³or importing fill material less than 50,000m³ are exempt from the C&DMMP. The new ETWB TCW No. 19/2005 “Environmental Management on Construction Sites” includes procedures on waste management requiring contractors to reduce the C&D material to be disposed of during the course of construction. Under ETWB TCW No. 19/2005, the Contractor is required to prepare and implement an Environmental Management Plan (EMP) and the WMP becomes part of the EMP.

6.2.9 The C&D material generated from the Project would be less than 50,000m³ and no importing of fill material would be required. As such, the Project is exempted from preparation of the C&DMMP.

Chemical Waste

6.2.10 Under the Waste Disposal (Chemical Waste) (General) Regulations, all producers of chemical waste must register with 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.

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:

Ÿ Identification of the quantity, quality and timing of the wastes generated;

Ÿ assessment of potential impacts from the management of wastes with respect to potential hazards, air and odour emissions, noise, wastewater discharges and public transport; and

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

6.4 Identification of Potential Sources of Impact

6.4.1 The construction activities to be carried out for the proposed Project will result in the generation of a variety of wastes which can be divided into distinct categories based on their composition and ultimate method of disposal. The identified waste types include:

Ÿ site clearance waste;

Ÿ construction and demolition (C&D) materials;

Ÿ chemical wastes; and

Ÿ general refuse.

6.5 Prediction and Evaluation of Environmental Impacts

6.5.1 The nature of each type of waste arising is described in the following section, together with an evaluation of the potential environmental impacts associated with the waste.

Site Clearance Waste

6.5.2 The majority of the road improvement works is widening of the existing TMRTCS. The need for site clearance would be limited and consist of wood, small amounts of low graded vegetation such as grass and small portion of topsoil.

6.5.3 It is considered that the handling and disposal of site clearance waste would not be a key issue and the potential environmental impact arising from handling and disposal of such waste would be negligible.

Construction and Demolition (C&D) Materials

6.5.4 C&D materials contain a mixture of inert and non-inert materials. The inert portion, such as soil, rock, concrete, brick and asphalt and etc., is the “public fill” and the non-inert portion, including metal, timber, paper, glass and general garbage is the “C&D waste”. The C&D materials will mainly arise from the road improvement works, demolition of existing footbridges, construction of flyover and noise barriers and re-provision of new footbridges. C&D materials comprise unwanted materials generated during construction, including rejected structures and materials, materials which have been over-ordered and materials which have been used and discarded. C&D waste may include:

Ÿ wood from tree felling, formwork and falsework;

Ÿ material and equipment wrapping;

Ÿ concrete rubble, metal and plastics from demolition of existing footbridges;

Ÿ unusable/surplus concrete/grouting mixes; and

Ÿ damaged/ surplus construction materials.

6.5.5 The Contractor is responsible for transfer of C&D materials to public fill reception facilities or landfills, depending on the type of material and the percentage of inert material. The public fill should be reused on site or disposed of to public fill reception facilities for beneficial uses. The non-inert portion of the C&D materials should be reused or recycled and, disposal of at landfills as the last resort.

6.5.6 The estimated volume of the C&D materials was estimated to be approximately 13,850m³, comprising of inert C&D material (public fill) and non-inert C&D material (C&D waste). The inert C&D material should be reused on-site as far as possible to minimise the net amount of C&D material generated from the Project. It is expected that 3,000m³ of the inert C&D materials would be reused on site and 5,850m³ of the surplus inert C&D materials would be disposed to public fill reception facilities for other beneficial uses. It is estimated that about 5,000m³ of C&D waste would be generated from general site clearance works, tree felling, piling works and formwork for viaduct and other highway structures. The C&D waste would require to be disposed of at the designated landfill. A breakdown of the estimated quantities of wastes from the different work areas of the Project is given in Table 6.1 below.

Table 6.1 Summary of Estimated Quantities of C&D Materials and Disposal Routes

Waste Type	Generated from Works Item	Total Quantity Generated	Handling	Quantity to be disposal off-site / reused
C&D Materials	Widening road works, demolition of existing footbridges, construction of flyover and noise barriers, re-provision of new footbridges, site clearance works, tree felling, piling works and formwork for viaduct and other highway structure	13,850 m³	Sort on-site into : · Inert C&D material (public fill) · C&D waste	Ø 5,850 m³ of inert C&D material (public fill) to be disposed to public fill reception facilities for other beneficial uses Ø 3,000 m³ of inert C&D material to be reused on-site Ø 5,000 m³of C&D waste to be disposed of at the designated landfill site
Chemical Wastes	Cleansing fluids, solvent, lubrication oil and fuel from construction plant and equipment	Few cubic metres per month (preliminary estimate)	Recycle on-site or by licensed companies Stored on-site within suitably designed containers	Chemical Waste Treatment Centre or other licensed facility
General Refuse	Waste paper, discarded containers, etc. generated from workforce	approx. 13 kg per day (preliminary estimate based on workforce of 20)	Provide on-site refuse collection points	Refuse station for compaction and containerisation and then to landfill

6.5.7 The main sources of excavated materials will be generated from the foundation construction along the alignment. Excavated materials are usually inert such as soil and rock which can normally be reused on site or in public fill reception facilities. The final destinations of the excavated materials to be disposed off-site for beneficial uses will be determined, subject to the availability of public fill reception facilities, by the Waste Management Plan to be submitted by the Contractors and agreed with CEDD.

6.5.8 C&D materials should be sorted on-site and separated public fill (inert portion) from C&D waste (non-inert portion). Due to the inert nature of most of the C&D materials generated, disposal would be unlikely to raise long-term environmental concerns. However, as some locations of the construction works areas would be in close proximity to roads and residential dwellings, improper management of waste may cause severe nuisance to local residents. Recommendations for the proper management of C&D materials are given in Section 6.6.

6.5.9 The generation of C&D materials is considered to be small and is not envisaged to have any adverse impact on the capacity of landfills and public fill reception facilities.

Chemical Wastes

6.5.10 The Waste Disposal (Chemical Waste) (General) Regulation defines chemical waste as any substance being scrap material or unwanted substances specified in its Schedule 1 and provides a complete list of such substances. However, substances likely to be generated by construction activities would mainly arise from the maintenance of equipment. These may include, but not be limited to, the following:-

Ÿ Scrap batteries or spent acid/alkali;

Ÿ Used engine oils, hydraulic fluids and waste fuel;

Ÿ Spent mineral oils/cleaning fluids from mechanical machinery; and

Ÿ Spent solvents/solutions, some of which may be halogenated, from equipment cleaning activities.

6.5.11 It is difficult to quantify the amount of chemical waste that will be generated 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 lubricating oil and solvent produced from plant maintenance, would be nominal and in the order of a few cubic metres per month. The amount of chemical waste to be generated will be quantified in the site Waste Management Plan to be prepared by the Contractor.

6.5.12 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:

Ÿ Toxic effects to workers;

Ÿ Adverse impacts on water quality from spills;

Ÿ Fire hazards; and

Ÿ Disruption of sewage treatment works where the chemical waste is allowed to enter sewerage system.

6.5.13 Materials classified as chemical wastes will require special handling and storage arrangements before removal for appropriate treatment at the Chemical Waste Treatment Centre (CWTC) or other licensed facility. Wherever possible opportunities should be taken to reuse and recycle materials. Mitigation and control requirements for chemical wastes are detailed in Section 6.6. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts would be negligible.

General Refuse

6.5.14 Throughout construction, the workforce would generate general refuse comprising food scraps, waste paper, empty containers, etc. Release of general refuse into the roadside gully/surface channel should not be permitted as introduction of these wastes is likely to have detrimental effects on water quality in the area. Rapid and effective collection of site wastes would be required to prevent waste materials being blown around by wind, flushed or leached into the aquatic environment, and odour nuisance. The work sites may also attract pests and vermin if the waste storage area is not well maintained and cleaned regularly. Disposal of refuse at sites other than approved waste transfer or disposal facilities can also result in similar impacts.

6.5.15 With the implementation of the recommended waste management practices at the site, adverse environmental impacts arising from the storage, handling and transportation of refuse would not be expected.

6.6 Mitigation Measures

Good Site Practices

6.6.1 It is not anticipated that adverse waste management related impacts would be arisen, provided that good site practices are adhered to. Recommendations for good site practices during the construction activities include:

Ÿ 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;

Ÿ Training of site personnel in proper waste management and chemical waste handling procedures;

Ÿ Provision of sufficient waste disposal points and regular collection for disposal;

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

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

Ÿ A recording system for the amount of wastes generated, recycled and disposed of (including the disposal sites).

Waste Reduction Measures

6.6.2 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:

Ÿ Segregation and storage of different types of waste in different containers, skips or stockpiles to enhance reuse or recycling of materials and their proper disposal;

Ÿ Encourage collection of aluminium cans, PET bottles and paper by providing separate labelled bins to enable these wastes to be segregated from other general refuse generated by the work force;

Ÿ Any unused chemicals or those with remaining functional capacity shall be recycled;

Ÿ Use of reusable non-timber formwork to reduce the amount of C&D material;

Ÿ 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;

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

Ÿ Plan and stock construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste.

6.6.3 In addition to the above measures, specific mitigation measures are recommended below for the identified waste arisings to minimise environmental impacts during handling, transportation and disposal of these wastes.