TABLE B1 IMPLEMENTATION
SCHEDULE
EIA Ref. |
EM&A Log Ref |
Environmental Protection Measures |
Location/Duration of Measures/Timing of Completion of Measures |
Implementation Agent |
Implementation Stage |
Relevant Legislation & Guidelines |
|||
Des |
C |
O |
Dec |
|
|||||
Mitigation Measures for both Grab Dredger and TSHD
Options |
|||||||||
3.11 |
A1 |
No dredging should be carried out at Working Zone BCs from February to April. |
Location: Working Zone BCs Timing/Duration: February to April |
HEC & Dredging Contractor |
|
a |
|
|
Wild Animals Protection Ordinance, Marine Parks Ordinance and Marine Parks Regulations, Animals and Plants Ordinance |
3.11 |
A2 |
Vessel route between the dredging site and the disposal sites should avoid the Finless Porpoise habitat area and be subject to a maximum speed limit of 10 knots in southern Lamma waters as indicated in Figure B3. |
Location: South Lamma Timing/Duration: During the Project period |
HEC & Dredging Contractor |
|
a |
|
|
Wild Animals Protection Ordinance, Marine Parks Ordinance and Marine Parks Regulations, Animals and Plants Ordinance |
5.2 |
A3 |
The number of dredgers and operation conditions specified in the applicable CNPs should be strictly followed. In applying for the CNPs, it should be ensured that the number of dredgers and operation conditions are compatible with the recommendations of this EIA. |
Location: The Project Area Timing/Duration: During restricted hours of the Project period |
HEC & Dredging Contractor |
|
a |
|
|
Noise Control Ordinance |
2.11.2 |
A4 |
The grab dredger option and TSHD option should not be operated concurrently. |
Location: The Project Area Timing/Duration: During the Project period |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO, Noise Control Ordinance |
EIA Ref. |
EM&A Log Ref |
Environmental Protection Measures |
Location/Duration of Measures/Timing of Completion of Measures |
Implementation Agent |
Implementation Stage |
Relevant Legislation & Guidelines |
||||
Des |
C |
O |
Dec |
|
||||||
Mitigation Measures for TSHD Option Only |
||||||||||
2.11.4 |
B1 |
Dredging works should be carried out in phases in accordance with the programme, number of dredgers and maximum dredging rates specified in Table B4. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO |
|
2.11 |
B2 |
There should not be more than one TSHD operating concurrently at any time. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO |
|
Mitigation Measures for Grab Dredger Option Only |
||||||||||
2.11.4 |
C1 |
Dredging works should be carried out in phases in
accordance with the programme, number of dredgers and maximum dredging rates
specified in Table B3. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO, Noise Control Ordinance |
|
2.8.12 |
C2 |
Each grab dredger to be deployed should have a grab
capacity of no less than 8 m3. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO |
|
2.12 |
C3 |
Cage-type silt curtains as illustrated in Figure B1 should be deployed for grab dredgers. The silt curtains should be properly maintained during the
dredging period. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO |
|
2.11 |
C4 |
There should be no more than 5 grab dredgers operating concurrently at any time. |
Location: The Project Area Timing/Duration: During dredging |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO, Noise Control Ordinance |
|
EIA Ref. |
EM&A Log Ref |
Environmental Protection Measures |
Location/Duration
of Measures/Timing of Completion of Measures |
Implementation
Agent |
Implementation
Stage |
Relevant
Legislation & Guidelines |
||||
Des |
C |
O |
Dec |
|||||||
Good Site Practice |
||||||||||
2.12 |
D1 |
Daily dredging volume should be spread as evenly as possible over the 24 hour period whenever practical. Special care should be taken during lowering and lifting grabs to minimize unnecessary disturbance to the seabed. |
Location: The Project Area, the disposal areas and on route between the dredging site and the disposal areas Timing/Duration: During dredging and disposal |
HEC & Dredging Contractor |
|
a |
|
|
WQOs for Southern and Western Buffer WCZs, WPCO |
|
|
|
Vessels used should have adequate clearance of the seabed. |
|
|
|
|
|
|
|
|
|
|
Barges should be fitted with tight fitting seals to their bottom openings to prevent leakage of material. |
|
|
|
|
|
|
|
|
|
|
Grabs should be tightly closed and hoist speed is suitably low. |
|
|
|
|
|
|
|
|
|
|
Barges should not be filled to a level which will cause overflow of materials during loading and transportation. |
|
|
|
|
|
|
|
|
|
|
Appropriate
monitoring of WQ in accordance with EM&A Manual during dredging works
should be undertaken to allow the implementation of appropriate Action Plans
to prevent any unacceptable WQ impacts. |
|
|
|
|
|
|
|
|
|
|
Large objects should be removed from the grab to avoid losses from partially closed grabs. |
|
|
|
|
|
|
|
|
EIA Ref. |
EM&A Log Ref |
Environmental Protection Measures |
Location/Duration of Measures/Timing of Completion of Measures |
Implementation Agent |
Implementation Stage |
Relevant
Legislation & Guidelines |
|||
Des |
C |
O |
Dec |
||||||
3.11 |
D2 |
The vessel operators should be fully briefed on the following: ·
Possible
presence of dolphins and porpoises in the vicinity of the Study Area and
along routes to the Project Area; ·
Rules for
safe vessel operation around cetaceans; · Slowing
to 10 knots in the presence of cetaceans within the area marked on Figure B3; and · The dumping of chemicals, rubbish, oils etc into the waters is strictly prohibited and enforced. |
Timing: In the event of spotting porpoises or dolphins |
Dredging Contractor |
|
a |
|
|
Wild Animals Protection Ordinance, Marine Parks Ordinance and Marine Parks Regulations, Animals and Plants Ordinance, Dumping at Sea Ordinance, Waste Disposal Ordinance |
Table B2 Recommended Maximum Daily/Hourly/Cycle Dredging Volume (in-situ Volume) for Working Zones
Season |
Wet Season (April to
September) |
Dry Season (October to March) |
|||||||
Working Zone |
ABn |
ABs |
BCn |
BCs |
ABn |
ABs |
BCn |
BCs |
|
Grab Dredger with
Silt Curtains (Grab Capacity ³ 8 m3) |
m3/day |
33,800 |
31,400 |
26,300 |
21,200 |
43,800 |
33,200 |
33,200 |
34,200 |
m3/hr |
1,549 |
1,439 |
1,205 |
972 |
2,008 |
1,522 |
1,522 |
1,568 |
|
TSHD |
m3/day |
12,500 |
11,300 |
8,300 |
5,300 |
39,500 |
34,300 |
27,000 |
19,700 |
m3/cycle |
1,432 |
1,295 |
951 |
607 |
4,526 |
3,930 |
3,094 |
2,257 |
Note:
(a) The recommended maximum dredging rate refers to the maximum dredging rates when all dredging activities taking place at one particular working zone. For the grab dredger option, dredging may be carried out concurrently at more than one working zones during some time periods. In this case, the combined dredging rates during those time periods should not exceed the lowest of the maximum rates recommended for the concerned working zones.
(b) The above maximum daily dredging rates are based on 24-hour operations. If the daily working hours are restricted, the maximum daily dredging rates should be reduced proportionally.
(c)
The
division of working zones are illustrated in Figure
B2.
(d)
For the grab dredger option, recommended maximum hourly dredging rate =
1.1 * recommended maximum daily dredging rate/24.
(e)
For the TSHD option, recommended maximum cycle dredging rate = 1.1 *
recommended maximum daily dredging rate/9.6 (where 9.6 is the number of
dredging cycle in a day assumed in water quality modelling).
Table B3 Proposed Working Schedule - Grab Dredger Option
Working Zone |
Construction Programme |
|||||||
May-03 |
Jun-03 |
Jul-03 |
Aug-03 |
Sep-03 |
Oct-03 |
Nov-03 |
Dec-03 |
|
ABn |
GD1 |
GD1 |
GD1 |
GD1 |
GD1 |
GD1 |
|
|
GD2 |
GD2 |
GD2 |
GD2 |
GD2 |
GD2 |
GD2 |
GD2 |
|
ABs |
GD3 |
GD3 |
GD3 |
GD3 |
GD3 |
GD3 |
GD3 |
GD3 |
GD4 |
GD4 |
GD4 |
GD4 |
GD4 |
|
|
|
|
BCn |
GD5 |
GD5 |
GD5 |
GD5 |
GD5 |
GD5 |
|
|
|
|
|
|
|
|
|
|
|
BCs |
|
|
|
|
|
GD4 |
GD4 |
GD4 |
|
|
|
|
|
|
GD5 |
GD5 |
|
|
|
|
|
|
|
GD1 |
GD1 |
|
Maximum dredging rate (m3/day) |
26,300 |
33,200 |
||||||
Maximum dredging rate (m3/hr) |
1,205 |
1,522 |
Note:
1.
GD1 denotes Grab Dredger No. 1.
2.
The above maximum daily dredging rates
are based on 24-hour operations. If the daily working hours are restricted, the
maximum daily dredging rates should be reduced proportionally.
Table B4 Proposed
Working Schedule - TSHD
Option
Working Zone |
Construction Programme |
|||||||
May-03 |
Jun-03 |
Jul-03 |
Aug-03 |
Sep-03 |
Oct-03 |
Nov-03 |
Dec-03 |
|
ABn |
TSHD |
|
|
|
||||
ABs |
|
|
|
|
|
|
TSHD |
|
BCn |
|
|
|
|
|
|
|
TSHD |
BCs |
|
|
|
|
|
TSHD |
|
|
Maximum dredging rate (m3/day) |
12,500 |
19,700 |
34,300 |
27,000 |
||||
Maximum dredging rate (m3/cycle) |
1,432 |
2,257 |
3,930 |
3,094 |
Note:
1.
TSHD denotes Trailer Suction Hopper Dredger
2.
The above maximum daily dredging rates
are based on 24-hour operations. If the daily working hours are restricted, the
maximum daily dredging rates should be reduced proportionally.