6 Waste Management

6.1 Introduction

6.1.1 This section identifies the type of wastes that would be likely to be generated during construction and operation phase of the Project and 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 widened TMR would generate wastes associated with roadside littering and road maintenance activities, and the amount would be expected to be minimal. The potential environmental impacts arising from the handling and disposal of the small quantity of waste are anticipated to be negligible and therefore have not been evaluated further 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 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 50,000m³ or 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.

Chemical Waste

6.2.9 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 estimation of the types and quantities 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 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 construction and demolition (C&D) material;

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 these waste arisings.

Construction and Demolition (C&D) Material

6.5.2 Construction and demolition (C&D) material would be generated from the road widening works, associated slope works and construction of noise barriers on Tuen Mun Road during the period March 2008 – October 2009. The types of C&D material during the construction works would be soil, fill and concrete. The estimated volume of the C&D material was estimated by the Project Engineer to be approximately 20,000m³, 1,500m³ of inert C&D material would be reused on site, 16,000m³ of inert C&D material would be disposed of to public fill reception facilities for other beneficial uses and 2,500m³ of C&D waste would be disposed of to designated landfills. A breakdown of the estimated quantities of C&D material 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 Material and Disposal Routes}

Waste Type	Generated from Works Item	Total Quantity Generated	Handling	Quantity to be re-used on-site	Quantity to be disposal off-site
C&D Material	Excavation, minor modification of slope and road works	20,000 m^3	Sort on-site into : · Inert C&D material (public fill) · C&D waste	1,500 m^3 of inert C&D material (public fill)	16,000 m^3 of inert C&D material (public fill) to be disposed of to public fill reception facilities for other beneficial uses 2,500 m^3 of C&D waste to landfill
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 Facility 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

General Refuse

6.5.3 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.

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

Chemical Wastes

6.5.5 The maintenance and servicing of construction plant and equipment may generate some chemical wastes such as cleaning fluids, solvents, lubrication oil and fuel. 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 lubricating oil and solvent produced from plant maintenance, would be limited 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.

6.5.6 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

6.5.7 Materials classified as chemical wastes will require special handling and storage arrangements before removal for appropriate treatment at the Chemical Waste Treatment Facility (CWTF) 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 6.7. Provided that the handling, storage and disposal of chemical wastes are in accordance with these requirements, adverse environmental impacts 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 arise, 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.

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.

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.

General Refuse

6.6.4 General refuse should be stored in enclosed bins or compaction units separate from C&D material. A reputable waste collector should be employed by the contractor to remove general refuse from the site, separately from C&D material. An enclosed and covered area is preferred to reduce the occurrence of 'wind blown' light material.

Chemical Wastes

6.6.5 After use, chemical wastes (for example, cleaning fluids, solvents, lubrication oil and fuel) should be handled according to the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes. Spent chemicals should be collected by a licensed collector for disposal at the CWTF or other licensed facility, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.

Construction and Demolition (C&D) Material

6.6.6 In order to minimise the impact resulting from collection and transportation of C&D material for off-site disposal, it is recommended that the excavated fill material shall be re-used on-site as backfill material as far as possible.

6.6.7 When disposing C&D material at a public fill reception facility, it shall be noted that the material shall only consist of earth, building debris and broken rock and concrete. The material shall be free from marine mud, household refuse, plastic, metals, industrial and chemical waste, animal and vegetable matter, and other material considered to be unsuitable by the Filling Supervisor.

6.7 Evaluation of Residual Impacts

6.7.1 With the implementation of the recommended mitigation measures for the handling, transportation and disposal of the identified waste arisings, no residual impact is expected to arise during the construction of the proposed Project.

6.8 Environmental Audit

6.8.1 Waste management will be the contractor’s responsibility to ensure that all wastes produced during the construction of the Project are handled, stored and disposed of in accordance with good waste management practices and EPD’s regulations and requirements. The mitigation measures recommended in Section 6.6 should form the basis of the site Waste Management Plan to be developed by the Contractor in the construction stage.

6.9 Conclusion

6.9.1 Wastes generated by the construction activities are likely to include C&D materials from the construction works, general refuse from the workforce and chemical waste from any maintenance of construction plant and equipment. Provided that these identified waste arisings are handled, transported and disposed of using approved methods and that the recommended good site practices are strictly followed, adverse environmental impacts would not be anticipated during the construction works.