13.1.1
This
section further elaborates the requirements of environmental monitoring and
audit (EM&A) for the construction and operation phases of the Project,
based on the assessment results of the various environmental issues. The objectives of carrying out EM&A for
the Project include the following:
·
Provide a database against which any short or long
term environmental impacts of the Project can be determined;
·
Provide an early indication should any of the environmental
control measures or practices fail to achieve the acceptable standards;
·
Monitor the performance of the Project and the
effectiveness of mitigation measures;
·
Verify the environmental impacts predicted in the EIA
study;
·
Determine project compliance with regulatory
requirements, standards and government policies;
·
Take remedial action if unexpected problems or
unacceptable impacts arise; and
·
Provide data to enable an environmental audit.
13.1.2
The
following sections summarise the recommended EM&A requirements for the
Project. Details of the specific
requirements are provided in a stand-alone EM&A Manual.
Construction Phase
13.2.1
With
the implementation of the dust suppression measures stipulated in the Air
Pollution Control (Construction Dust) Regulation, good site practices and
proposed mitigation measures on the work sites and barging points, no adverse
dust impact would be expected at the ASRs in the vicinity of the construction
sites. Dust monitoring and site audit
requirement during construction phase of the Project have been recommended in
the EM&A Manual to ensure that the mitigation measures are to be properly
implemented.
Operational Phase
13.2.2
Since no adverse operation air quality impact would be expected, hence
no monitoring and audit is required during operation phase.
Construction Phase
13.3.1
An
EM&A programme is recommended to be established
according to the expected occurrence of noisy activities. All the recommended mitigation measures for
daytime normal working activities should be incorporated into the EM&A
programme for implementation during construction. Details of the EM&A requirements are
provided in the EM&A Manual.
Operation Phase
13.3.2
The
assessment has indicated that the noise from ventilation buildings and pumping
station would comply with the EIAO-TM standards. Having said
that, monitoring of operation noise from the proposed ventilation buildings and
pumping station during the testing and commissioning stage would be recommended
to verify the compliance of the EIAO-TM criteria.
13.3.3
Road
traffic noise monitoring should be carried out during the first year and after
road opening at representative NSRs located in the vicinity of the recommended
direct mitigation measures. Details of
the programme are provided in the EM&A Manual.
Operational
Phase
13.4.1
As
adverse water quality impact will not be generated from the operation of the
TKO-LT Tunnel Project (Section 5.10), operational water quality monitoring and
audit is not considered necessary. However,
a four-week post-construction water quality monitoring will be carried out on
completion of marine works. Details of
the monitoring programme are provided in the EM&A Manual.
13.4.2 After completion of the tunnel construction, a 1-year post-monitoring on the groundwater levels (piezometer monitoring) above the tunnel will need to be carried out by contractor responsible for tunnel construction. The frequency of groundwater level monitoring should be proposed by the Engineer and agreed with the EPD.
Construction Phase
13.4.3
A
water quality monitoring and audit programme will be conducted before and
during filling operations to verify whether or not impact predictions are
representative, and to ensure that the filling operations do not result in
unacceptable impacts. When monitoring
shows unacceptable water quality impact, appropriate mitigation measures, such
as re-scheduling of construction programmes might need to be considered to slow
down construction activities (e.g. to reduce the number of plant) to minimise the
impacts.
13.4.4
Details
of the EM&A programme will be presented in the standalone EM&A
Manual. Water quality monitoring will be
carried out at selected potentially affected sensitive receivers. The Manual includes site-specific monitoring
and auditing protocols for baseline and impact monitoring. Such protocols include but are not limited to
the locations of monitoring stations, parameters and frequencies for
monitoring, monitoring equipment, data management procedures, and reporting of
monitoring results.
13.4.5
Environmental
audit specifications will be developed for all phases of the works, including
procedures to ensure compliance with mitigation measures, environmental quality
performance limits, and procedures for reviewing results and auditing
compliance with specified performance limits.
13.4.6 Environmental controls on groundwater during the tunneling contract would consist of 3 periods of monitoring: Baseline, Construction and Post-Construction (as stated in Section 13.4.2) piezometer monitoring to control the work:
Baseline
13.4.7
Baseline controls each year, or as directed by the Engineer – a full
suite of hourly monitoring for a 26 hour period, wet and dry season, spring and
neap tides. Concurrently, tidal
reference shall also be taken hourly from the tide gauge measurement at Quarry
Bay for each of the four monitoring periods.
On the basis of the four sets of results the Engineer will define an
acceptable baseline groundwater envelope for the tunnel section of TKO-LT
Tunnel project, for the two seasons and two tides.
Construction Monitoring
13.4.8
Daily piezometer monitoring, at a time of day
to be agreed with the Engineer, will be required throughout the whole period
when any tunnel construction activities are carried out within +/- 50m of the piezometer gate in plan.
13.4.9
The frequency of monitoring may be increased, as directed by the
Engineer, should the monitored groundwater levels step outside the defined
acceptable groundwater envelope for the particular gate, season and tide.
13.4.10
Additional ad hoc piezometer monitoring may be
ordered by the Engineer, if any form of recharge is required to restore the
local groundwater to the acceptable envelope or that any part of the Action
Plan (as defined in the EIA Table 5.18) has to be invoked as a consequence of
the passage of the tunnel drive.
13.4.11
Water quality monitoring should also be conducted at the four streams
within the assessment area as identified in Section 6 (locations refer to Figure
6.3, Stream 1 to 4) to prevent drying out of streams and any contamination
to the groundwater due to tunnel construction.
Water quality parameters including DO, pH, temperature, turbidity, SS, BOD5, TOC Total Nitrogen,
Ammonia-N and Total Phosphate are recommended.
Terrestrial Ecology
13.5.1
As
only minor impacts on terrestrial ecology are identified, no monitoring
programme specific for terrestrial ecology is required. However, the implementation of all mitigation
measures for terrestrial ecological impact described in Section 6.8 should be subject to regular
audit.
Marine Ecology
13.5.2
Water
quality monitoring and audit designed to detect and mitigate any unacceptable
impact on water quality will also serve to proactively protect marine
ecological resource against water quality deterioration. Regular site audits should be carried out to
ensure the effective implementation of mitigation measure stated in Section 6.8.
13.5.3
To
avoid and minimize potential loss of small and sparsely distributed coral
colonies found within the directly impacted area as well as to minimize the
shading effect, it is recommended to translocate the directly impacted corals
except Oulastrea crispata
attached on the movable (< 50 cm in diameter) boulders / rocks within
the proposed reclamation area and bridge footprint, as far as practicable, to a
nearby suitable recipient site where similar hydrographic
condition and healthy coral communities of the same coral species were
recorded. Coral translocation should be
carried out during the winter season (November-March) in order to avoid
disturbance to the transplanted colonies during the spawning period (i.e. July
to October). A detailed translocation
plan with brief description on pre-translocation coral survey, translocation
methodology, identification of coral recipient site and post-translocation
monitoring methodology should be prepared during the detailed design stage of
the Project. Pre-translocation survey on
coral within the reclamation area would be focused on identifying and mapping
the coral colonies that would be directly impacted by the proposed marine works
and investigating the translocation feasibility of these coral colonies (e.g.
health status of coral colony and nature of the attaching susbtrata). The detailed translocation plan and marine
ecologists involved in coral translocation should be approved by relevant
authorities (e.g. EPD & AFCD) prior to commencement of the translocation
exercises.
13.5.4
Information
gathered during each post-translocation monitoring survey should include
observations on the presence, survival, health condition and growth of the translocated coral colonies. These parameters should then be compared with
the baseline results collected from the pre-translocation survey.
13.5.5
The
untranslocable coral colonies of low coverage (<
1%) would be loss, while those that are unaffected by the direct loss would
potentially be impacted by the indirect water quality change arising from the
reclamation works. It is therefore
recommended to monitor these nearby coral communities along with the water
quality monitoring programme during the construction phase with a view to
protect the natural coral communities in vicinity of the proposed marine works
areas.
13.6.1
No
unacceptable fisheries impact is expected from the project. No monitoring program specified for fisheries
is required.
13.7
Waste
Management Implications
13.7.1
Waste
management will be the contractor’s responsibility to ensure that all wastes
produced during the construction of the Project are handled, stored and
disposed of in accordance with the recommended good waste management practices
and EPD’s regulations and requirements.
The mitigation measures recommended in Section 8 should form the basis of the site
Waste Management Plan to be developed by the Contractor at the construction
stage.
13.7.2
It
is recommended that the waste arisings generated
during the construction activities should be audited periodically to determine
if wastes are being managed in accordance with approved procedures and the site
Waste Management Plan. The audits should
look at all aspects of waste management including waste generation, storage,
recycling, transport and disposal. An
appropriate audit programme would be to undertake a first audit near the
commencement of the construction works, and then to audit on a quarterly basis
thereafter. In addition, the routine
site inspections should check the implementation of the recommended good site
practices and other waste management mitigation measures.
13.8
Impact
on Cultural Heritage
13.8.1
To
ensure no damage to the Cha Kwo Ling Tin Hau Temple,
monitoring of the indirect impact such as monitoring of vibration should be
conducted during the construction phase.
13.9
Landscape
and Visual Impact
Construction Phase
13.9.1
It
is recommended that professionally qualified Resident Site Landscape Architect
supervise and monitor the implementation of construction phase landscape and
visual mitigation measures. This is necessary to ensure the minimisation of the
works footprint, to ensure that topsoil is saved for re-use, to ensure that
those existing trees earmarked for retention on site or transplanting are
protected and to monitor advance screen planting works and the effectiveness of
temporary screen hoardings and all the recommended landscape and visual
mitigation measures under Chapter 10 of the EIA. Regular site inspections
should be undertaken to closely monitor all these aspects of the work.
Operational Phase
13.9.2
During
the Operational Phase, landscape and visual mitigation measures should be
monitored during the first 10 years to check that the intended mitigation
effects are realised. Regular monitoring should be undertaken to ensure that
the landscape and visual mitigation measures have been implemented, are
effective and are being managed and maintained. The compensatory tree planting
required to offset the loss of existing trees, and the
additional planting works for screening, slope stabilisation and amenity
purposes should be checked. Planting must be established and become sustainable
to provide long term landscape and visual mitigation. Hardworks
elements that have been provided as part of the new works or as the
reinstatement of impacted works should also be monitored and checked that they
are being maintained and are achieving their mitigation function.
13.10
Landfill Gas Hazard Assessment
13.10.1
A
landfill restoration monitoring programme, conducted on a monthly basis, is
part of the Urban Landfills Restoration Contract on the Sai Tso Wan Landfill.
However, landfill gas monitoring is still considered necessary during the
construction and operational phase in order to identify any migration between
the landfill and the Project sites and to ensure the safety of the Contractor’s
personnel.
Construction Phase
13.10.2
During
construction activities within 250m Consultation Zones of Sai Tso Wan Landfill,
a Safety Officer, trained in the use of gas detection equipment and landfill
gas-related hazards, should be present on site throughout the groundworks phase. The Safety Officer should be provided
with an intrinsically safe portable instrument, which is appropriately
calibrated and able to measure methane, carbon dioxide and oxygen.
13.10.3
Routine
monitoring should be carried out in all excavations, manholes, chambers,
relocation of monitoring wells and any other confined spaces that may have been
created. All measurements in excavations
should be made with the extended monitoring tube located not more than 10 mm
from the exposed ground surface.
Monitoring should be performed properly to make sure that the area is
free of landfill gas before any man enters into the area.
13.10.4
For
excavations deeper than 1m, measurements should be carried out:
·
at the ground surface before
excavation commences;
·
immediately before any worker enters the
excavation;
·
at the beginning of each working day
for the entire period the excavation remains open; and
·
periodically throughout the working day whilst
workers are in the excavation.
13.10.5
For
excavations between 300mm and 1m deep, measurements should be carried
out:
·
directly after the excavation has been
completed; and
·
periodically whilst the excavation remains
open.
13.10.6 For excavations less than 300mm
deep, monitoring may be omitted, at the discretion of the Safety Officer or
other appropriately qualified person.
13.10.7 The exact frequency of monitoring
should be determined prior to the commencement of works, but should be at least
once per day, and be carried out by a suitably qualified or qualified person
before starting the work of the day.
Measurements shall be recorded and kept as a record of safe working
conditions with copies of the site diary and submitted to the Engineer for
approval.
Operational Phase
13.10.8 During operation, regular
monitoring of methane, carbon dioxide and oxygen should be done at the tunnel,
subway, and any other underground structures within the landfill consultation
zone a precautionary measure.
13.10.9 Inspection and LFG monitoring should
be carried out at buildings and enclosures (e.g. administration building,
ventilation building, workshop, tunnel etc) prior to the operation as
preventive measures. The monitoring
should be continued through the operation of the Project. In particular for the first year of
operation, monthly monitoring is recommended.
Should the monitoring reveal the presence of landfill gas within the
tunnel, buildings or other confined area, the seal of the joints shall be inspected
and consideration shall be given to seal the cracks.
13.10.10 In addition, if any construction
is required for the maintenance work during operational stage, the responsible
party should follow the monitoring works as recommend in Clauses 13.10.02 to
13.10.7 of this section and Clauses 11.5.26 to 11.5.31 of this
report.
13.10.11
The
monitoring programme and detailed actions should be submitted to EPD for
approval in the detailed design stage.