TABLE OF CONTENTS

 

 

5                                                                                                                                                                                                                                                                                     WASTE MANAGEMENT IMPLICATIONS                                                                                                                                                                                                                                                                                     5-1

5.1                                                                                                                                                                                                                                                                                     Introduction                                                                                                                                                                                                                                                                                     5-1

5.2                                                                                                                                                                                                                                                                                     Waste Control and Mitigation Measures                                                                                                                                                                                                                                                                                     5-1

 

 

List of Tables

 

 

List of Figures

 

 

Appendices

 

 

 


5                        WASTE MANAGEMENT IMPLICATIONS 

5.1                  Introduction

5.1.1           Waste management would be the contractor’s responsibility to ensure that all wastes produced during the construction phase for the drainage improvement works are handled, stored and disposed of in accordance with good waste management practices and EPD’s regulations and requirements. 

5.1.2           Waste materials generated during construction activities, such as construction and demolition (C&D) material, chemical wastes and general refuse, are recommended to be audited at regular intervals (at least quarterly) to ensure that proper storage, transportation and disposal practices are being implemented. The Contractor would be responsible for the implementation of any mitigation measures to minimise waste or redress problems arising from the waste materials.

 

5.2                 Waste Control and Mitigation Measures

5.2.1           Mitigation measures for waste management are summarised below. With the appropriate handling, storage and removal of waste arisings during the construction works as defined below, the potential to cause adverse environmental impacts would be minimised. The implementation schedule of the recommended mitigation measures is presented in Appendix A. During the site inspections, the ET should pay special attention to the issues relating to waste management and check whether the Contractor has implemented the recommended good site practices and other mitigation measures.

 

Good Site Practices

5.2.2           Appropriate waste handling, transportation and disposal methods for all waste arisings generated during the construction works should be implemented to ensure that construction wastes do not enter the river and stream channels, and that no waste, spoil and/or excavated materials will be dumped/stockpiled in the adjacent ecological habitats such as marsh, agricultural land, woodland, shrubland, plantation area and fishpond.

5.2.3           It is expected that adverse impacts from waste management would not arise, provided that good site practices are strictly followed.  Recommendations for good site practices during construction include:

·        nomination of approved personnel, such as a site manager, to be responsible for good site practices, and making arrangements for collection of all wastes generated at the site and effective disposal to an appropriate facility;

·        training of site personnel in proper waste management and chemical waste handling procedures;

·        provision of sufficient waste disposal points and regular collection for disposal;

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

·        regular cleaning and maintenance programme for drainage systems, sumps and oil interceptors;

·        a recording system for the amount of wastes generated, recycled and disposed (including the disposal sites) should be proposed; and

·        a Waste Management Plan should be prepared and submitted to the Engineer for approval.  One may make reference to ETWB TCW No. 15/2003 for details.

5.2.4           In order to monitor the disposal of C&D material at landfills and public filling areas, as appropriate, and to control fly tipping, a trip-ticket system should be included as one of the contractual requirements to be implemented by an Environmental Team undertaking the Environmental Monitoring and Audit work.  One may make reference to WBTC No. 21/2002 for details.

 

Waste Reduction Measures

5.2.5           Good management and control can prevent the generation of significant amounts 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: 

·        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;

·        separate labelled bins should be provided to segregate aluminium cans from other general refuse generated by the workforce, and to encourage collection of by individual collectors;

·        any unused chemicals or those with remaining functional capacity should be recycled;

·        maximising the use of reusable steel formwork to reduce the amount of C&D material;

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

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

·        plan and stock construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste; and

·        minimize over ordering of concrete, mortars and cement grout by doing careful check before ordering.

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

 

Construction and Demolition Material

5.2.7           The C&D material generated from the river improvement works would comprise public fill, being excavated soil, gravel and boulders.  To minimise off-site disposal of public fill, the excavated material with suitable characteristics/size should be reused on-site as fill material as far as practicable, such as for backfilling of box culverts and drainage pipes, and small cobbles and rocks should be used in the construction of the recreated channel bed. 

5.2.8           When disposing C&D material at a public filling area, it should be noted that the material should only consist of soil, rock, concrete, brick, cement plaster/mortar, inert building debris, aggregates and asphalt.  The material should 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. 

5.2.9           The C&D material generated from demolition of existing structures and river crossings should be sorted on-site into inert C&D material (that is, public fill) and C&D waste.  Suitable areas should be designated within the works site boundaries for temporary stockpiling of C&D material.  Within stockpile areas, the following measures should be taken to control potential environmental impacts or nuisance:

 

·        covering material during heavy rainfall;

·        locating stockpiles to minimize potential visual impacts; and

·        minimizing land intake of stockpile areas as far as possible.

 

Excavated Riverbed Material

5.2.10       It is anticipated that the excavated riverbed material may need to be temporarily stockpiled on-site prior to disposal off-site.  Details of environmental control measures to be taken at the stockpiling area to prevent water pollution are discussed in Section 5.  Use of water-tight trucks would be required for the transportation of excavated riverbed material to the designated barging point for disposal at the designated public filling area, or transported directly to the public filling area. 

 

Chemical Wastes

5.2.11       If chemical wastes are produced at the construction site, the Contractor would be required to register with the EPD as a Chemical Waste Producer and to follow the guidelines stated in the Code of Practice on the Packaging, Labelling and Storage of Chemical Wastes. Good quality containers compatible with the chemical wastes should be used, and incompatible chemicals should be stored separately.  Appropriate labels should be securely attached on each chemical waste container indicating the corresponding chemical characteristics of the chemical waste, such as explosives, flammable, oxidizing, irritant, toxic, harmful, corrosive, etc.  The Contractor should use a licensed collector to transport and dispose of the chemical wastes generated at the Chemical Waste Treatment Centre at Tsing Yi, or other licenced facility, in accordance with the Waste Disposal (Chemical Waste) (General) Regulation.

 

General Refuse

5.2.12       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.