6.0....... WASTE MANAGEMENT IMPLICATION ASSESSMENT
6.1 Introduction
6.2
Environmental Legislation, Standards and
Guidelines
6.3
Description of the Environment
6.4 Assessment Methodologies. 6-2
6.5
Identification of Potential Impacts
6.6
Mitigation of Adverse Environmental
Impacts
6.7
Evaluation of Residual Impacts
6.8
Environmental Monitoring and Audit
6.9
Conclusion
This
section identifies the types of waste which are likely to be generated during
the construction and operation phases of the Project, and evaluates the
potential environmental impacts that may be resulted from the waste generation.
Mitigation measures and good site practices,
including waste handling, storage and disposal, have been recommended with
reference to relevant waste legislation and management guidelines.
The criteria and
guidelines for accessing waste management implications are outlined in Annexes
7 and 15, respectively, of the Technical Memorandum on Environmental Impact
Assessment Process (EIAO-TM).
The following legislation, which has been used
in assessing potential impacts, relates to the handling, treatment and disposal
of wastes in the Hong Kong SAR:
•
Waste Disposal
Ordinance (Cap. 354);
•
Waste Disposal
(Chemical Waste) (General) Regulation (Cap. 354C);
•
Waste Disposal
(Charges for Disposal of Construction Waste) Regulation (Cap. 354N);
•
Land (Miscellaneous
Provisions) Ordinance (Cap. 28);
•
Public Health and
Municipal Services Ordinance (Cap. 132) - Public Cleansing and Prevention of
Nuisances Regulation (Cap 132BK); and
Other relevant
documents and guidelines are also applicable to waste management and disposal
in Hong Kong:
•
WBTC No. 2/93 Public
Dumps;
•
WBTC No. 2/93B Public
Filling Facilities;
•
WBTC No. 12/2000 Fill
Management;
•
ETWB TCW 19/2005
Environmental Management on Construction Sites;
•
DEVB TCW No. 06/2010
Trip Ticket System for Disposal of Construction and Demolition Materials;
•
DEVB TCW No. 08/2010
Enhanced Specification for Site Cleanliness and Tidiness;
•
DEVB TCW No. 09/2011
Enhanced Control Measures for Management of Public Fill;
•
Hong Kong Planning
Standards and Guidelines Planning, 2016 (PlanD)
•
Code of Practice on
the Packaging, Labelling and Storage of Chemical Wastes (EPD);
•
A Guide to the
Chemical Waste Control Scheme (EPD); and
•
Section 4.1.3 of
Chapter 4 of the Project Administration Handbook (PAH) for Civil Engineering
Works, Management of Construction/Demolition Materials including Rocks.
The Project is located at Kam Tin Road section
between Tung Wui Road and Lam Kam Road; and Lam Kam Road section between Kam
Tin Road and Kadoorie Farm. Land use in the vicinity of the Project includes
residential use, open storage, Government, Institution or Community facilities
and commercial use.
The
assessment of the environmental impacts arising from the handling, storage,
collection, transportation and disposal of waste material generated by the
Project is undertaken in accordance with Annexes 7 and 15 of the EIAO-TM. The
potential waste management implications of the Project have been assessed by:
•
Estimation on types and quantities of waste generated;
•
Determination of potential impacts arising from waste management in
terms of potential hazards, air and odour emissions, noise, wastewater
discharge and emission due to public transport;
•
Examination of the opportunities of reducing waste generation;
•
Identification of disposal options for each type of waste; and
Prior to considering the disposal options for various types of waste,
opportunities for reducing waste generation, on-site or off-site reuse and
recycling have been evaluated. Practices to promote segregation of waste
materials are also considered to enhance the efficiency of waste management.
Considering all the opportunities for reducing waste generation and
maximizing reuse, the types and quantities of the waste required to be disposed
of have been estimated and the disposal options for each type of waste have
been described. The disposal method recommended for each type of waste has
taken into account the result of the assessment. The impacts caused by handling
(including stockpiling, labelling, packaging and storage), collection and reuse
/ disposal of waste have been addressed and appropriate mitigation measures
have been proposed.
Construction
Phase
The main construction activities which will potentially result in the
generation of wastes in this Project include:
(i)
Site Clearance & Utility Diversion;
(ii)
Road Upgrading Works (Backfill and reinstatement works);
(iii) Street Furniture
& Soft Landscape Works;
(iv) Excavation and
Lateral Support (ELS) Works (Sheet piling and excavation works);
(v) Foundation and
Substructure Works (Rebar fixing and concreting works);
(vi) Geotechnical Works
(Construction of retaining structures and slope upgrading works); and
(vii) Construction of
Superstructure Works (Noise mitigation works), if necessary.
The construction activities to be carried out for 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 types of waste
generated include:
•
Construction and demolition (C&D) materials;
• Chemical waste; and
• General refuse
No dredged sediment or excavated mud will be generated from the
Project.
C&D Materials
C&D materials would be generated from the construction
activities of the Project during the course of the works between Year 2021 and
2025. The construction programme is subject
to review depending on the progress of the Project. It is estimated that the total volume of the C&D
materials generated from the Project would be approximately 42,320m3.
All C&D materials generated shall be sorted on
site into inert portion “inert C&D materials” including soil, building
debris, broken rock, concrete, etc., and the non-inert portion is the
"C&D wastes" comprising timber, paper, plastics, general refuse
etc. The inert C&D materials, the reusable and/or recyclable materials
shall be recovered before disposal of the waste portion off site as a last
resort. The surplus portion
of the inert C&D materials may be transported to the public fill reception
facility at Tuen Mun Area 38 for beneficial reuse, and the C&D wastes at
North East New Territories (NENT) Landfill in Ta Kwu Ling. It is estimated that 32,970m3
of inert C&D material (public fill) to be disposed of at public fill
reception facility at Tuen Mun Area 38 for other beneficial uses, 2,690m3
of inert C&D material to be reused on-site, and 6,660m3 of
non-inert C&D waste to disposed of at NENT landfill.
Different kinds of wooden materials are essential to
the construction project. All wooden materials used on site should be kept
separated from other wastes. Wooden boards will be reused on site several times
until the quality of the boards is no longer suitable for re-use. On completion
of construction project, remaining reusable wooden material will be sorted and
used at other construction sites by the contractor.
Reusable steel and concrete panels shall be used as a
preferred alternative to wooden formwork, falsework, and site fencing.
Methods to minimise the generation of C&D materials
will be addressed during detail design and in planning of the construction
works. A Waste Management System will be incorporated into the Waste Management
Plan (WMP) to effectively manage and avoid/reduce/minimise the generation of
C&D material during construction.
To prevent fly-tipping of C&D materials, a Trip
Ticket System will be implemented to monitor C&D wastes from the Project, a
truck carrying debris should first obtain a ticket on leaving the construction
site, then dump the debris at the designated location and finally have the
ticket stamped and returned to the construction site.
Chemical Waste
Construction plant and vehicle maintenance may
generate a small amount of chemical wastes during construction works, such as
cleaning fluids, solvents, lubrication oil and fuel.
The volume of chemical waste is difficult to quantify
since it will depend upon the maintenance requirements and total number of
plant utilised on site. However, the potential volume of chemical waste would
be limited and anticipated in few cubic metres per month. The amount of
chemical waste to be generated will be quantified in the site WMP to be
prepared by the contractor.
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 facilities.
Wherever possible opportunities should be taken to reuse and recycle materials.
Storage, handling, transport and disposal of chemical
waste should be arranged in accordance with the Code of Practice on the
Packaging, Labelling and Storage of Chemical Waste published by the EPD. Provided that chemical waste is disposed
of at a licensed chemical waste treatment and disposal facility, the potential
environmental impacts arising from the storage, handling and disposal of a
small amount of chemical waste generated from the construction activities will
be negligible.
General Refuses
The workforce would generate refuse comprising food
scraps, waste paper, empty containers, etc. Such refuse will be properly collected
on-site and transfer to the nearby refuse collection point. Disposal of refuse at sites other than
approved waste transfer or disposal facilities will be prohibited. Effective collection of site wastes will
prevent waste materials being blown around by wind, or creating an odour
nuisance or pest and vermin problem.
Waste storage areas will be well maintained and cleaned regularly.
The maximum number of construction workers to be
employed is estimated to be about 80 workers. Based on a generation rate of 0.65 kg
per worker per day, the maximum daily arising of general refuse during the
construction period would be approximately 52 kg and this waste can be
effectively controlled by normal measures.
With the implementation of good waste management practices at the site,
adverse environmental impacts are not expected to arise from the storage,
handling and transportation of workforce wastes.
Based on the assessment above, Table 6.1 presents the
estimated volume of waste generation.
In general, the inert portion of C&D materials should be disposed of
at public fill reception facilities while the non-inert portion should be sent
to landfill for disposal. Any potential for reuse of materials on site should
be explored prior to disposal.
Table 6.1 Summary of Waste Generation during Construction
Phase
|
Material Type |
Source(s) |
Quantity |
Handling |
Disposal/Treatment |
|
C&D Materials |
Excavation, minor modification of slope and road
works |
Total = 42,320 m3 |
Sort on-site into inert C&D material (public
fill) and non-inert C&D waste 2,690 m3 of inert C&D material
reused on-site |
32,970 m3 of inert C&D material
(public fill) to be disposed of at public fill reception facility at Tuen Mun
Area 38 for other beneficial uses 6,660 m3 of non-inert C&D waste to
NENT landfill |
|
Wooden Material (reusable as lower grade shuttering
or fencing on-site or other sites) |
Final disposal to NENT Landfill |
|||
|
Scrap metals (Reusable steel panels shall be used
as site fencing) |
To NENT Landfill if rejected by recycling companies |
|||
|
Chemical Waste |
Cleansing fluids, solvent, lubrication oil and fuel
from construction plant and equipment |
A few cubic metres per month (preliminary estimate) |
Reuse on-site or recycle by licensed companies and
stored on-site in the suitable containers |
To Chemical Waste Treatment Centre or other
licensed facility |
|
General Refuse |
Waste paper, discarded containers, etc. generated
from workforce |
Approximate 52 kg per day (preliminary estimate
based on workforce of 80) |
Provide on-site refuse collection points |
To NENT landfill |
Disposal
Routes for C&D Materials in Construction Phase
Non-inert C&D waste will be transported to NENT Landfill for
disposal via Lam Kam Road, Fanling Highway, Sha Tau Kok Road and Wo Keng Shan
Road. The number of vehicle trips is estimated to be very low, only one or two
trips per day, as the quantity of C&D waste and general refuse to be
disposed of is very low.
There will be no stockpiling area. Inert C&D material will be
transported to the public fill reception facility at Tuen Mun Area 38 via Kam
Tin Bypass, Castle Peak Road and Lung Mun Road. Throughout the construction and
demolition period this will average at three to four vehicle trip per day.
Operation
Phase
Upon Project operation, it is anticipated that major source of wastes
would only be from roadside littering. Types of waste to be generated include:
•
General refuse
General Refuses
Road side litters include food
scraps, waste paper, empty containers, etc. Sufficient rubbish bins/recycling bins
will be provided. Such refuse will
be collected by Food and Environmental Hygiene Department or relevant
departments for disposal.
Significant impacts from waste
are not predicted, nonetheless, mitigation measures are required to ensure that
proper handling, storage, transportation and disposal of material are
undertaken. Measures will also be required to ensure that the generation of
waste is avoided and minimised where possible and that waste materials are
recycled and treated as far as practicable. Recommended mitigation measures for
different categories of waste are detailed below.
Best Management Practice
The proposed mitigation measures are as below:
•
An on-site environmental co-ordinator should be identified at the
outset of the works. The
co-ordinator shall prepare an Environmental Management Plan (EMP) incorporating
waste management in accordance with the requirements set out in the ETWB TCW
No. 19/2005, Environmental Management on Construction Sites. The EMP shall
include monthly and yearly Waste Flow Tables (WFT) that indicate the amounts of
waste generated, recycled and disposed of (including final disposal site), and
which should be regularly updated. WFT will be provided in the WMP which will
form part of the EMP in accordance with ETWB TCW No.19/2005;
•
The reuse/ recycling of all materials on site shall be investigated
prior to treatment/ disposal off- site;
•
Good site practices shall be adopted from the commencement of works to
avoid the generation of waste, reduce cross contamination of waste and to
promote waste minimisation;
•
All waste materials shall be sorted on-site into inert and non-inert
C&D materials, and where the materials can be recycled or reused, they
shall be further segregated. Inert
material, or public fill will comprise stone, rock, masonry, brick, concrete
and soil which is suitable for land reclamation and site formation whilst
non-inert materials include all other wastes generated from the construction
process such as plastic packaging and vegetation (from site clearance);
•
The contractor shall be responsible for identifying what materials can
be recycled/ reused, whether on-site or off-site. In the event of the latter,
the contractor shall make arrangements for the collection of the recyclable
materials. Any remaining non-inert
waste shall be collected and disposed of to the landfills whilst any inert
C&D materials shall be re-used on site as far as possible. Alternatively,
if inert materials cannot be reused on-site, the materials would be delivered
to public fill reception facilities for beneficial reuse after obtaining the
appropriate licence;
•
With reference to DEVB TCW No.6/2010, Trip-ticket System for Disposal
of Construction and Demolition Material, a trip ticket system should be
established at the outset of the construction to monitor the disposal of
C&D and solid wastes from the site to public filling facilities and
landfills;
•
Under the Waste Disposal (Chemical Waste) (General) Regulation, the
Contractor shall register as a Chemical Waste Producer if chemical wastes such
as spent lubricants and paints are generated on site. Only licensed chemical
waste collectors shall be employed to collect any chemical waste generated at
site. The handling, storage, transportation and disposal of chemical wastes
shall be conducted in accordance with the Code of Practice on the Packaging,
Labelling and Storage of Chemical Wastes and A Guide to the Chemical Waste
Control Scheme both published by EPD;
•
A sufficient number of covered bins shall be provided on site for the
containment of general refuse to prevent visual impacts and nuisance to the
sensitive surroundings. These bins
shall be cleared daily and the collected waste disposed of to the refuse
transfer station. Further to the issue of DEVB TCW No. 8/2010, Enhanced
Specification for Site Cleanliness and Tidiness, the contractor is required to
maintain a clean and hygienic site throughout the Project works;
•
All chemical toilets, if any, shall be regularly cleaned and the
night-soil collected and transported by a licensed contractor to a Government
Sewage Treatment Works facility for disposal;
•
Tool-box talks should be provided to workers about the concepts of site
cleanliness and appropriate waste management procedures, including waste
reduction, reuse and recycling; and
•
The contractor shall comply with all relevant statutory requirements
and guidelines and their updated versions that may be issued during the course
of Project construction.
Storage, Collection and Transportation of Waste
C&D materials
In order to monitor, document and verify the disposal
of C&D materials at landfills and public fill reception facilities, as
appropriate, and to control fly tipping, a trip-ticket system in accordance
with DEVB TC(W) No. 6/2010 Trip Ticket System for Disposal of Construction and
Demolition Materials should be implemented.
The C&D materials generated from excavation works
and construction works should be segregated from other waste to avoid
contamination and ensure acceptability at the public fill reception facilities
or suitable construction sites. They should be sorted on-site into inert
C&D materials (that is, public fill) and non-inert C&D waste. To
minimise the impact resulting from collection and transportation of C&D
materials as far as practicable, non-inert C&D waste, such as wood,
plastic, steel and other metals should be reused or recycled and, as a last
resort, disposed to landfill. The trucks for the transportation of waste will
be with covering for the open-box or with enclosed container to minimise dust
emission during transportation. A suitable area should be designated within the
site for temporary stockpiling of C&D materials and to facilitate the
sorting process. Within the stock pile areas, the following measures should be
taken to control potential environmental impacts or nuisance:
•
Waste such as soil should be handled and stored well to ensure secure
containment;
•
Covering materials during heavy rainfall;
•
Stockpiling area should be provided with covers and water spraying
system to prevent materials from wind-blown or being washed away;
•
Locating stockpiles to minimise potential visual impacts; and
•
Minimising land intake of stockpile area as far as possible.
The Contractor should be responsible for devising a
system to work for on-site sorting of C&D materials. It is recommended that
the system should include the identification of the source of generation,
estimated quantity of waste generated, arrangement for on-site sorting and / or
collection, designated stockpiling areas, frequency of collection by recycling
contractors and frequency of removal off-site.
All dusty materials should be sprayed with water
prior to any loading, unloading or transfer operation so as to maintain the
dusty materials wet.
Chemical Wastes
If chemical waste is produced at the construction
site, the Contractor will 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. Chemical waste should
be stored in appropriate containers and collected by a licensed chemical waste
collector. Chemical waste (e.g. spent lubricant oil) should be disposed of at
either the CWTC, or another licensed facility, in accordance with the Waste
Disposal (Chemical Waste) (General) Regulation.
General Refuses
General refuse should be stored in enclosed bins
separately from construction and chemical waste. Recycling bins should also be
placed to encourage recycling. Enclosed and covered areas should be provided
preferably for general refuse collection and routine cleaning for these areas
should also be implemented to keep areas clean. A reputable waste collector
should be employed to remove general refuse on a daily basis. It is expected
that such arrangements would minimise potential environmental impacts.
With the implementation of the recommended mitigation
measures for the handling, transportation and disposal of the identified waste
arising, adverse residual impact is not expected during the construction and
operation phases of the Project.
Construction Phase
It is 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 the recommended good waste management
practices and relevant legislation and waste management guidelines.
It is recommended that the waste arisings generated
during the construction activities should be audited regularly by the
Environmental Team (ET) to determine if wastes are being managed in accordance
with approved procedures. The audits should look at all aspects of on-site
waste management practices including waste generation, storage, recycling,
transport and disposal. Apart from site inspections, documents including licences,
permits, disposal and recycling records should be reviewed and audited for
compliance with the legislation and Contract requirements. In addition, the
routine site inspections should check the implementation of the recommended
good site practices and other waste management mitigation measures.
A WMP, as part of the EMP should be prepared in
accordance with ETWB TC(W) No. 19/2005 and submitted to the Engineer, i.e.
Resident Engineer appointed by the Employer to oversee the construction works
in accordance with the specification and contractual requirement for approval.
The recommended mitigation measures should form the basis of the WMP. The
monitoring and auditing requirement stated in ETWB TC(W) No. 19/2005 should be
followed with regard to the management of C&D materials.
Operation Phase
It is expected that there would be limited quantities
of waste to be generated from the operation of the Project and will be properly
handled by Food and Environmental Hygiene Department or relevant departments.
Waste monitoring and audit programme for the operation phase of the Project
would not be required.
With the implementation of the mitigation measures
during the construction and operation phases of the Project, no significant
waste management impacts are anticipated. The implementation of the
mitigation measures shall be included to the works contracts. Regular site
inspections are recommended during construction phase to ensure the measures
are implemented properly.