1. Fugitive Dust CONTROL MEASURES

1.1 Establishment Phase

1.1.1 The dust control measures required under the Air Pollution Control (Construction Dust) Regulation should be implemented. Working areas where excavation or earthmoving operation are taking place shall be sprayed with water or a dust suppression chemical. Any stockpiling of excavated material shall be covered by impervious sheeting or sprayed with water or a dust suppression chemical. The following site facilities shall also be provided as part of the establishment phase to prevent potential dust impact during the fill bank operation and decommissioning:

· Erect site hoarding of at least 2.4m high along the northern and eastern boundaries of the site except at the site entrance/ exit. Before occupation take place at the Recovery Park Phase I and II, site hoarding of at least 2.4m high should also be erected along the western boundary of the fill bank;

· Install/ refurnish vehicle wheel washing facilities including high pressure water jets provided at designated vehicle exit points;

· Pave/ refurnish designated main haul roads with concrete, bituminous materials, hardcores or metal plates;

· At the barging point, the drop height between the barge and dump trucks shall be minimized;

· Tipping halls provided for transfer of public fill from trucks to barges shall be top and 3-sides enclosed.

1.2 Operational Phase

1.2.1 Any works that involve the stockpiling of dusty materials are regulated under the Air Pollution Control (Construction Dust) Regulation as regulatory work. In accordance with the requirements of the Air Pollution Control (Construction Dust) Regulation, sufficient dust control/ mitigation measures shall be implemented to ensure full protection of the nearby Air Sensitive Receivers (ASRs). The dust control measures that are considered to be particularly relevant to the operation (and decommissioning) of the fill bank are summarised below.

Site Haul Road

1.2.2 Public fill delivery trucks entering or leaving the fill bank shall be required to follow the designated main haul route that is covered with concrete, bituminous materials, hardcores or metal plates. The main haul roads provided for regular transport of public fill from the barge handling area to the public fill stockpiling area shall also be constructed with similar materials to minimise dust emissions. The main haul roads for delivery of public fill by trucks shall be routed away from the eastern boundary of the fill bank. Water lorries and/or road sweepers shall be provided and used in dust suppression. The designated main haul roads shall be watered at approximately every 2 hours to ensure that the roads are kept sufficiently dampened. Truck speed shall be controlled to within 10 km/hr. Trucks using the fill bank should be checked to have valid dumping licence. The buffer distance between the designated haul roads and the nearby ASRs has been optimised based on the current design of the fill bank.

Loading/ unloading of Public Fill

1.2.3 All dusty fill material shall be sprayed with water or a dust suppression chemical prior to loading, unloading or transfer so as to maintain the fill material wet, except for situations where the moisture content of the dusty material is a matter of concern. Frequent water (at least three times per day) of the worksites with active dusty operations is recommended. The frequency shall be increased when the weather is dry.

1.2.4 Loading of public fill delivered by barges to the site shall be sprayed with water at the material landing point to minimize dust emission except when the materials are sufficiently dampened when landed. Any mist spraying applied should only dampen the dusty material and overwatering should be avoided.

Site Entrance/ Exit

1.2.5 Vehicle washing facilities including high pressure water jet installed at the existing exits shall be maintained and operated by designated staff to ensure that these dust control measures are being used. Before leaving the fill bank site, every vehicle shall be washed to remove any dusty materials from its body and wheels.

1.2.6 Trucks carrying dusty load entered to the site shall be sprayed with water once the impervious sheeting covering the load is removed.

Stockpiling of Public Fill

1.2.7 Based on the preliminary design of the fill bank with respect to the area allocated for stockpiling of public fill, a minimum buffer distance of 20 m shall always be maintained between the edge of the public fill stockpiling area of the fill bank and the nearest air sensitive receivers at the River Trade Terminal. Within the buffer zone, no dusty material shall be stockpiled and no loading/ unloading and similar activities should be allowed. As shown in Figure 7, an area of 100m x 100m in the north-eastern corner of the stockpiling area shall be managed by the contractor as a “truckload control zone”. Number of trucks travelling to the control zone shall be limited to a maximum of 64 vehicles per hour, and a daily maximum of 633 vehicles per day. Similarly, a minimum buffer zone of 20 m shall be maintained between the edge of the public fill stockpiling area and the nearest air sensitive land uses at Recovery Park Phase I and Phase II along the western boundary of the site.

1.2.8 Stockpiling activities at the fill bank shall be administrated by the contractor with care in proper manner to minimise dust emissions from loading/ unloading activities and wind erosion, and to avoid segregation, deterioration, erosion or instability of the stockpiled material.

1.2.9 The portions of site and stockpiling height allocated by the project engineers in the stockpiling of public fill shall be followed in the daily operation of the fill bank. Temporary slope surfaces shall be covered with tarpaulin sheets or other impermeable sheets, or sprayed with water or a dust suppression chemical, or protected by other methods approved by CED. The amount of mist spraying should be just enough to dampen the material surface without over-watering, which could otherwise result in unnecessary surface water runoff. Final slope surfaces shall be treated by compaction, followed by hydroseeding, vegetation planting or other suitable surface stabiliser approved by CED to prevent the washing away of stockpiled material.

Transfer of Material with Belt Conveyor System

1.2.10 Any belt conveyor systems used for transfer of dusty materials shall be enclosed on top and 2 sides. Every transfer point between two conveyors shall be totally enclosed. An effective belt scraper or equivalent device shall be installed at the head pulley of every belt conveyor to dislodge fine particles that may adhere to the belt surface, and to reduce carrying back of fine particles on the return belt. The belt conveyer shall be equipped with bottom plates or other similar means to prevent falling of material from the return belt. Every stockpiling belt conveyor shall be provided with a mechanism to adjust its level such that the vertical distance between the belt conveyor and the material landing point is maintained at no more than 1m. Dusty material loaded from a belt conveyor outlet to stockpiles, storage bins, trucks, barges and other open areas shall be sprayed with water or a dust suppression chemical.

General Site Management

1.2.11 Appropriate working methods should be devised and arranged to minimise dust emissions and to ensure any installed air pollution control system and measures are operated in accordance with their design merits. In the event of malfunctioning of any control system or equipment, the relevant dusty activities shall stop until the relevant control system or equipment are restored to proper functioning.

1.2.12 Frequent mist spraying should be applied on dusty areas. The frequency of spraying required will depend upon local meteorological conditions such as rainfall, temperature, wind speed and humidity. The amount of mist spraying should be just enough to dampen the material without over-watering.

1.3 Decommissioning Phase

1.3.1 The dust control measures recommended for the operational phase shall continue to be applicable during the decommissioning phase of the project. During loadout of material from the stockpiling area of the fill bank, the material handled shall also be sprayed with water or a dust suppression chemical before and after the transfer of material so as to maintain the entire surface of the material sufficiently dampened. At the 100m x 100m “control zone”, loadout of material shall be limited to a maximum of 64 truckloads per hour and 633 truckloads per day. The contractor shall implement these measures in accordance with the requirements of the Air Pollution Control (Construction Dust) Regulation. The vertical distance between barges and material unloading platform at the barging point shall be minimized in operation to reduce dust generation. The tipping hall at the barging point shall be enclosed on top and three sides. All public fill delivery trucks carrying dusty load leaving the fill bank shall be required to be covered entirely by clean impervious sheeting in prior to ensure that the dusty materials do not leak from the vehicles.

1.4 Environmental Monitoring and Audit

1.4.1 The implementation of the above dust control measures shall be checked by an Environmental Monitoring and Audit (EM&A) programme.

2. Noise Management

2.1.1 The following noise management measures are recommended to be implemented by the contractor as good site practices during the establishment, operation and decommissioning of the fill bank.

Construction Noise Management

· All construction works should be carried out during the non-restricted hours (i.e. 7:00 a.m. to 7:00 p.m. on weekdays other than General Holidays);

· Before the commencement of any work that may generate a significant noise impact, the Contractor should submit to the Engineer for approval the method of working, equipment and sound-reducing measures (e.g. use of silenced type of equipment) intended to be used

Operational/ Decommissioning Phase Noise Management

· The noise standards specified in the Technical Memorandum for the Assessment of Noise from Places Other Than Domestic Premises, Public Places or Construction Sites shall be met;

· The fill bank should not be in operation from 8:00 p.m. to 8:00 a.m. the next day;

3. Water Quality Control Measures

3.1.1 Potential water quality impact during the establishment, operation and decommissioning of the fill bank shall be controlled with the following as basic principles:

· Prevent or minimise the likelihood of the identified pollutants being in contact with rainfall or runoff; and

· Measures to abate pollutants in the stormwater runoff.

3.1.2 These principles shall be achieved through the implementation of adequately designed water quality control measures as Best Management Practices (BMPs). The guidelines for handling and disposal of construction site discharges as detailed in EPD’s ProPECC Note PN1/94 “Construction Site Drainage” should be followed.

Provision of Stormwater Interception Facilities and Buffer Zone

3.1.3 Trapezoidal surface channels should be constructed to intercept polluted surface runoff. These channels shall be equipped with sand/ de-silting traps such that the effluent discharged from the site during the establishment, operation and decommissioning phases will meet the discharge limits specified in the Technical Memorandum on Standards for Effluents Discharged into Drainage and Sewerage Systems, Inland and Coastal Waters. Annex IV shows the typical design of sand trap (CED Drawing No. GC 1034).

3.1.4 Before completion of the surface drainage channels at the commencement of the project, earth bunds and sand bag barriers shall be used at required locations to effectively divert stormwater to available drainage channels constructed under the reclamation works. The temporary drainage facilities provided shall allow polluted stormwater to be diverted to existing intercepting channels before stockpiling of public fill should begin. The intercepting channels shall be equipped with sand/ silt removal facilities to allow the stormwater to be treated before discharge at the designated outfalls. Effluent discharged shall meet the relevant discharge limits specified in the Technical Memorandum.

3.1.5 To minimise potential water quality impact associated with polluted surface water runoff, a minimum buffer distance of 50m will be provided between the edge of the stockpiling area of the fill bank and the seafront. Open channels and/or other effective drainage system shall be constructed at the perimeter of the site for intercepting and directing runoff to sand/ silt removal facilities prior to discharge. The unpaved area on the seaward side of the channels shall be covered with gravel and formed with slope so that polluted stormwater will be intercepted by the channels.

Excavated Material generated during Establishment

3.1.6 Any excavated material generated near the seafront (e.g. from the construction of the barging point) not required to be backfilled immediately should be transported away from the seafront to avoid potential water quality impact especially during the rainy season.

Sorted Public Fill

3.1.7 Public fill transported to the stockpiling area for storage should not contain unsuitable material such as peat, vegetation, timber, organic, soluble or perishable material, dangerous or toxic material, floatable materials (such as bottle, plastic bags, foam box), and materials susceptible to combustion.

Surface Protection Measures for Slope

3.1.8 Public fill at the stockpiling area should be handled with care in proper manner that will not result in segregation, deterioration, erosion or instability of the material. The designated positions for the unloading of fill material in the daily operation of the fill bank should be followed. Temporary slope surfaces shall be covered as far as practicable and as soon as possible with tarpaulin sheets or other impermeable sheets, or protected by other methods approved by CED when rainstorms are likely, especially when a rainstorm is imminent or forecast. Final slope surfaces shall be treated by compaction, followed by hydroseeding, vegetation planting or other suitable surface stabiliser approved by CED to prevent the washing away of stockpiled material.

Maintenance of Sand/ Silt Removal Facilities

3.1.9 Adequately designed and constructed catchpits, sand and silt removal facilities and intercepting channels should be maintained, and the deposited silt and grit should be removed weekly and on a need basis especially during the onset of and after each rainstorm to ensure that these facilities are functioning properly at all times during the establishment, operation and decommissioning phases.

Wheel Washing Facilities

3.1.10 All vehicles and plant bodies should be cleaned before they leave the fill bank site to ensure that no earth, mud or debris is deposited by them on roads. A wheel washing bay should be provided at the site exit and wash-water should have sand and silt settled out or removed before the water is being reused or discharged into storm drains. The section of construction road between the wheel washing bay and the public road should be paved with concrete, bituminous materials or hardcores to reduce vehicle tracking of soil and to prevent site run-off from entering public road drains.

Wastewater from Site Facilities

3.1.11 Sewage from toilets and similar facilities should be discharged into a foul sewer, or chemical toilets should be provided. Should the use of chemical toilets be necessary, these should be provided by a licensed contractor, who will be responsible for appropriate disposal and maintenance of these facilities. Wastewater collected from canteen kitchens, including that from basins, sinks and floor drains, should be discharged into foul sewers via grease traps. Drainage system provided at car parking areas shall be provided with oil interceptors in addition to sand/ silt removal facilities.

Use of Barges

3.1.12 All barges used in the transportation of fill material during the operation/ decommissioning stages should be properly licensed under the Shipping and Port Control Ordinance, and of appropriate size such that adequate clearance is maintained between the vessels and the sea bed at all states of the tide to ensure that undue turbidity is not generated by turbulence from vessel movement or propeller wash. All vessels used for transportation of fill material should have tight fitting seals to their bottom openings to prevent leakage of material during transport. For the transfer of public fill from the berthing barges to Tuen Mun Area 38, the following design measures shall be specified in the Technical Specification as environmental protection measures:

· When backhoe fixed on an appropriately design flat-top pontoon is in use, the reach of the backhoe shall be controlled to within the flat-top pontoon of sufficient length to avoid accidental dropping of public fill into the sea;

· When hopper barges with mobile crane is in use, guardrails or equivalent shall be fixed alongside the berthing faces to guide the movement of the crane to avoid accidental dropping of fill material into the sea;

· When derrick barges with built-in crane are in use, the reach of the jig shall be controlled to within the length of the barge to avoid accidental dropping of public fill into the sea

3.1.13 These recommended measures for transfer of public fill from barges to the fill bank are illustrated in Figure M1 through Figure M3. The design of the specific transfer methods shall be as such that the pathway of material delivery from barge to the waterfront will not be directly on top of the marine water to effectively prevent the dropping of material to the sea. Should other equivalent transfer methods and environmental protection measures are proposed by the future contractor, these shall be subject to approval of CED and DEP.

3.1.14 Barges should not be filled to a level which may cause overflow of material during loading or transportation. Barge effluents (e.g. muddy water) should be properly collected and treated prior to disposal. The work activities should not cause any visible foam, oil, grease, scum, litter or other objectionable matters to be present on the water in the vicinity of the barging point.

3.1.15 A waste collection vessel shall be deployed to remove floating refuse on the sea near the fill bank for proper disposal.

Construction Site Drainage Guidelines

3.1.16 Other best management practices to reduce stormwater and non-point source pollution recommended under ProPECC PN 1/94 on Construction Site Drainage should be properly followed.

3.1.17 The Contractor shall be responsible for the design and implementation of the water pollution control measures. If the above measures are not sufficient to restore any water quality impact monitored to acceptable levels, upon gaining advice through discussion with the Independent Environmental Checker (IEC) and Engineer’s Representative (ER) and the contractor, the Environmental Team (ET) shall propose some other mitigation measures for implementation by the Contractor. The ET shall carry out regular site audit to ensure timely implementation of the BMPs by the contractor.

Environmental Monitoring and Audit

3.1.18 The implementation of the above water pollution control measures shall be checked by an Environmental Monitoring and Audit (EM&A) programme.

4. Landfill Gas Migration Protection Measures

4.1.1 Main site offices of the fill bank shall be constructed within the site area lying outside the 250m consultation zone of the restored Siu Lang Shui landfill. The container office(s) to be set up at the site entrance/ exit which is situated within the consultation zone of the landfill shall be constructed on a raised hollow platform, or equivalent measure should be provided.

4.1.2 No underground structures such as drainage and sewage systems, underground pipelines and chambers shall be constructed at the site area lying within the consultation zone. Access to the fill bank by the general public shall be restricted.

4.1.3 During the establishment, operation and decommissioning phases of the fill bank, hazards may arise as a result of the flammability of landfill gas or its potentially asphyxiating properties. It is advisable to include appropriate specified clauses for incorporation in the contract documents for the project. In general, the contractor should be aware of, and should inform supervisor and workers of the following:

· Methane and carbon dioxide are always likely to be present in the soil voids;

· Physical and chemical nature of landfill gas;

· Methodologies for landfill gas detection;

· Fire and explosion hazards associated with landfill gas;

· Toxicity effects and health hazards associated with landfill gas;

· Potential health effects from direct contact with leachate/ groundwater contaminated by leachate; and

· Provide the contingency measures for leachate/ groundwater contamination

4.1.4 Precautions should be clearly laid down and rigidly adhered for activities such as excavation, trenching and creation of confined or semi-confined spaces, if any, carried out within the consultation zone of the restored landfill. In addition to normal site safety procedures, gas detection equipment and appropriate breathing apparatus should be available and used when entering confined spaces or trenches deeper than 2 metres.

4.1.5 Personnel entering the site shall be fully informed of the risk associated with potential landfill gas exposure.

4.1.6 Concentration of methane, carbon dioxide and oxygen within the manholes or the like shall also be checked in prior and confirmed to be within a safe level before any workers shall enter any enclosed space situated within the consultation zone of the restored landfill.

4.1.7 Safety measures including the following should be covered in the contract document:

· Proper warning of the potential hazards in the vicinity of excavation works at existing ground level;

· Appropriate training for workers who work in, or have responsibility for “at risk” areas;

· Preparation of an excavation procedure or code of practice for excavation works at existing ground level;

· Prohibition of smoke and naked flames within any ground level excavation or ground-level confined space;

· Proper control of welding, flame-cutting or other hot works from any trench, confined spaces or excavation area;

· Proper location for mobile offices, equipment stores, mess rooms, etc.;

· Provision of adequate fire extinguishing equipment, fire-resistant clothing and breathing apparatus;

· Preparation of a “method-of-working” statement covering all normal and emergency procedures before beginning of any required drilling operations.

4.1.8 On the unlikely events that any sign of leachate or leachate-contaminanted groundwater be encountered during the establishment, operation or decommissioning phases of the fill bank, the landfill operator should be informed so that this can be collected for proper treatment and disposal.

5. Landscape and Visual Control Measures

5.1.1 Hydroseeding or coloured geo-textile matting (dark green/ brown) shall be provided on the slopes of the fill bank along the eastern, northern and western sides of the fill bank as the slopes of each layer of platform are formed. A buffer tree planting strip should be provided along the northern perimeter of the site where space permits as shown in Figure 12. A row of approximately 3m high native evergreen tree species with a tall habit when fully grow (e.g. Casuarina equisetifolia) shall be planted at the early establishment/ operational phase of the project. To ensure the effective implementation of these measures, a Government approved landscape contractor will be hired to undertake and maintain the hydroseeding and tree planting works.

5.1.2 The design, colour and finish of structures at the fill bank should be such that they are visually recessive. Reflectivity should be reduced through selection of material or surface treatment. The surface colour selected should be of an earthy tone with strong natural qualities (e.g. green/ grey/ brown). Use of bold colour schemes should be avoided. The existing 2.4m high site hoarding located along Lung Mun Road should be maintained to help screening of the fill bank.

Figure M1

Figure M2

Figure M3