APPENDIX A - IMPLEMENTATION SCHEDULE OF THE PROPOSED MITIGATION MEASURES

 

Table A.1        Implementation Schedule for Water Quality Control

EIA Ref #

Environmental Protection Measures / Mitigation Measures

Location / Timing

Implementation Agent

Implementation Stages*

Relevant Legislation and Guidelines

Des

C

O

Dec

S3.60

Measures to be implemented during dredging:

·      Use of a closed grab dredger with a maximum daily production rate of 500 m3/day;

·      Deployment of silt curtain to enclose the grab while dredging works are in progress.  This layer of silt curtain shall be a frame type silt curtain and designed to enclose local pollution caused by the grab dredging.  It shall consist of floats, curtain and ballast at the bottom.  Mid-ballast may be added as necessary.  The Contractor shall install the silt curtain prior to dredging and shall remove it upon completion of dredging. In case the baseline water quality monitoring data indicates low ambient suspended solids concentrations of less than 12.5mg/l, a second silt curtain shall be deployed around the project site (i.e. hanging type silt curtain) and the dredging rate lowered to 250 m3/day.  The second layer of silt curtain shall be formed from tough, abrasion-resistant permeable membranes, supported on floated booms in such a way as to ensure that egress of turbid waters from the enclosed dredging area shall be restricted; and

·      Use of small sized hopper barge and dredger for dredging works.  The maximum draft of the dredger and hopper barge, when fully loaded, shall not exceed 2m.  The hopper barge shall make more frequent trips to transport the dredged material to the allocated marine disposal ground, instead of remaining at Lung Kwu Chau until it is fully loaded, in order to avoid grounding of the barge during low tide.

 

Work site / During the construction period & maintenance dredging

Contractor

 

Ö

Ö

 

EIAO-TM, WPCO

S3.61

Good site practices to be undertaken during marine works:

·      Mechanical grabs shall be designed and maintained to avoid spillage and sealed tightly while being lifted;

·      All vessels shall be sized such that adequate clearance (i.e. minimum clearance of 0.6m) is maintained between vessels and the seabed in all tide conditions, to ensure that undue turbidity is not generated by turbulence from vessel movement or propeller wash;

·      All pipe leakages shall be repaired promptly and plant shall not be operated with leaking pipes;

·      The decks of all vessels shall be kept tidy and free of oil or other substances that might be accidentally or otherwise washed overboard. Litter and loose objects, e.g. tools, shall not be left lying around.  Wires and ropes shall be coiled and secured, so as to cause least obstruction. Cylindrical shape items (such as pipes), heavy objects/equipment and stagings/scaffoldings on deck shall be lashed securely against the rolling movement of vessels.  Doors shall be properly secured to open or closed position to prevent swinging as the vessel rolls;

·      Adequate freeboard (i.e. minimum of 200mm) shall be maintained on barges to ensure that decks are not washed by wave action;

·      All hopper barges and dredgers shall be fitted with tight fitting seals to their bottom openings to prevent leakage of material;

·      Construction activities shall not cause foam, oil, grease, scum, litter or other objectionable matter to be present on the water within the site or dumping grounds; and

·      Loading of barges and hopper barges shall be controlled to prevent splashing of material into the surrounding water.  Barges or hopper barges shall not be filled to a level that will cause the overflow of materials or sediment laden water during loading or transportation.

 

Work site / During the construction period & maintenance dredging

Contractor

 

Ö

Ö

 

 

S3.62

Demolition and removal works of the submerged portion of the existing jetty shall be carried out around low tide to minimize the duration of works taking place within the marine waters.

Work site / During the construction period

Contractor

 

Ö

 

 

 

# All recommendations and requirements resulted during the course of EIA/EA Process, including ACE and/or accepted public comment to the proposed project.

* Des - Design, C - Construction, O – Operation, and Dec - Decommissioning

Table A.2        Implementation Schedule for Ecological Requirements

EIA Ref #

Environmental Protection Measures/Mitigation Measures

Location/ Timing

Implementation Agent

Implementation Stages*

Relevant Legislation and Guidelines

Des

C

O

Dec

S4.31

Mitigation for terrestrial ecology

 

·      Reinstate temporary work sites/disturbed areas immediately after completion of the construction.

 

·      Check the work site boundaries regularly to ensure they are not exceeded and that no damage occurs to surrounding natural habitats.

 

·      Prohibit and prevent open fires within the work site boundary during construction and provide temporary fire fighting equipment in the work areas.

 

Work site / During the construction period

Contractor

 

Ö

 

 

EIAO-TM

S4.88

General mitigation for Chinese White Dolphin

 

·      The use of high-speed vessels in the construction or operation of the jetty shall be avoided where possible.  If high-speed vessels must be used, they shall be required to slow to under 10 knots which is the speed restriction for all marine traffic inside the Marine Park Boundary. Furthermore, marine traffic entering the Marine Park to the proposed jetty area shall follow a regular and predictable route.

 

·      All vessel operators working on the project shall be given a briefing, alerting them to the conservation significance of the Marine Park and the presence of dolphins in the area, and setting out guidelines for safe vessel operations around cetaceans. 

 

·      A policy of no dumping of rubbish, food, oil, or chemicals shall be strictly enforced.  This shall also be covered in the contractor briefing.

 

·      Every attempt shall be made to minimize the effects of construction and operation of the jetty on the water quality of the area. Dredging works for the approach channel shall be scheduled outside the period of late spring to summer (i.e. May-August), when dolphins are at their peak abundance in North Lantau waters.

 

·      Before dredging, an exclusion zone of 500m radius shall be scanned around the work area for at least 30 minutes prior to the start of dredging.  If dolphins are observed in the exclusion zone, marine works shall be delayed until they have left the area. Furthermore, if dolphins enter the exclusion zone after dredging has commenced, marine works shall cease until they have left the area.

 

·      Staff shall monitor for the presence of dolphins within the exclusion zone by scanning the sea both with and without binoculars whilst positioned at vantage point near the summit of the hill behind the jetty location. The vantage point shall enable an extensive view of the 500m exclusion zone in all directions around the jetty. Staff shall communicate with the Engineer via a dedicated telecommunications device (e.g. mobile phone or ‘walkie-talkie’).

 

Work site / During the construction and operation periods

Contractor

 

Ö

Ö

 

 

S4.88

Mitigation for minimising possible noise impacts on dolphins

 

·      Other measures recommended to mitigate noise impact on dolphins by allowing their acclimatization to noise disturbance are to, as far as practicable:

 

-        The dredging works for the approach channel shall avoid the period of late spring to summer (i.e. May-August).

 

-        The number of work vessels and small craft shall be minimised during the construction phase.

 

-        Dredging and jetty construction activities shall be continuous without short breaks or unpredictable noise outbursts at random intervals.

 

-        Events shall be scheduled on a regular basis with similar activities planned for similar time period each day.

 

-        Furthermore, the Contractor shall use quiet or ‘silenced’ plant equipment.  All site plant equipment shall be well maintained.

 

·   Removal of the existing jetty structure shall be done in a way that minimise noise impact on dolphins by following the above recommended measures. Blasting shall not be permitted. Silenced breakers shall be used and demolition and removal works of the submerged portion of the jetty shall be carried out around low tide to minimise transmittance of noise into the water.  In addition, demolition of the jetty structure shall be planned so that, as far as practicable, the structure is ‘cut’ into large manageable sections to minimise the amount of time breakers are used.

 

·   During the operational phase, vessels moored at the jetty for extended periods shall, as far as practicable, turn off their engines to minimise unnecessary underwater noise.

 

Work site / During the construction and operation period

Contractor

 

Ö

Ö

 

 

# All recommendations and requirements resulted during the course of EIA Process, including ACE and / or accepted public comment to the proposed project.

* Des - Design, C - Construction, O - Operation and Dec - Decommissioning

Table A.3        Implementation Schedule for Waste Management

EIA Ref #

Environmental Protection Measures / Mitigation Measures

Location / Timing

Implementation Agent

Implementation Stages*

Relevant Legislation and Guidelines

Des

C

O

Dec

S7.26 – S7.27

Marine Sediment

 

In accordance with the WBTC No.3/2000, the material must be dredged, transported and disposed of in a manner which  minimizes the loss of contaminants either into solution or by resuspension.

During transportation and disposal of the dredged marine sediments, the following measures shall be taken to minimise potential impacts on water quality.

 

·         Bottom opening of barges shall be fitted with tight fitting seals to prevent leakage of material.  Excess material shall be cleaned from the decks and exposed fittings of barges and hopper dredgers before the vessel is moved.

·         Monitoring of the barge loading shall be conducted to ensure that loss of material does not take place during transportation.  Transport barges or vessels shall be equipped with automatic self-monitoring devices as specified by the Director of Environmental Protection.

 

Work site / During the construction period & maintenance dredging

Contractor

 

Ö

Ö

 

WBTC No.3/2000

S7.29

Good Site Practices and Waste Reduction Measures

 

Good site practices during the construction activities include:

 

·         Nomination of an approved personnel, 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;

·         Training of site personnel in proper waste management procedures;

·         High standards of waste management shall be observed on the works vessels and barges to ensure that no waste arisings or fuel/diesel oils are disposed to the surrounding marine waters;

·         Careful control shall be exercised during the demolition works and strict waste management procedures will be required to ensure that no C&D materials and machinery fuels enter the marine waters at the site;No stockpiles of construction material shall be permitted on Lung Kwu Chau Island;

·         All wastes, unused construction materials and construction equipment shall be removed from Lung Kwu Chau Island after the works are completed;

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

·         In order to monitor the disposal of C&D materials at public filling areas, and to control fly-tipping, a trip-ticket system shall be included as one of the contractual requirements. One may make reference to WBTC No. 5/99 for details; and

·         A Waste Management Plan shall be prepared and this WMP shall be submitted to the Engineer for approval. One may make reference to WBTC No. 29/2000 for details

 

Work site / During the construction period

Contractor

 

Ö

 

 

Waste Disposal Ordinance (Cap.54)

WBTC No.5/99, 29/2000

S7.30

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:

·         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;

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

·         Plan use of construction materials carefully to minimise amount of waste generated and avoid unnecessary generation of waste.

 

Work site / During planning & design stage, and construction stage

Contractor

Ö

Ö

 

 

WBTC No.4/98, 5/98

# All recommendations and requirements resulted during the course of EIA/EA Process, including ACE and / or accepted public comment to the proposed project.

* Des - Design, C - Construction, O – Operation, and Dec - Decommissioning

Table A.4        Implementation Schedule for Landscape and Visual

EIA Ref #

Environmental Protection Measures / Mitigation Measures

Location / Timing

Implementation Agent

Implementation Stages*

Relevant Legislation and Guidelines

Des

C

O

Dec

S8.70

·         Sympathetic design to minimise visual impact including rounded jetty cope line and irregular armour rocks on catwalk.

·         Compatible design and construction materials and finishes e.g. granite stone facing, visually recessive colours or finishes of “jetty furniture”.

·         Avoidance of light glare impact to Lung Kwu Tan villagers to be taken into account during design of lighting system for jetty and catwalk by EMSD.

 

Work site / During planning & design stage

CED/EMSD

 

Ö

 

 

 

 

 

S8.70

 

·         Reinstatement of disturbed land.

 

Work site / During construction stage

Contractor

 

Ö

 

 

 

# All recommendations and requirements resulted during the course of EIA/EA Process, including ACE and / or accepted public comment to the proposed project.

* Des - Design, C - Construction, O – Operation, and Dec - Decommissioning