EXECUTIVE SUMMARY
The Project “Landslide Preventive Works at Po Shan,
Mid-levels – Design and Construction (Natural Terrain Risk Mitigation Works)”
(hereafter called “the Project”) includes the installation of about 700 numbers
of soil nails and about 60 numbers of raking drains on the natural terrain
within the concerned area.
China State – China Railway Joint Venture (CCJV) was
commissioned as the Contractor of the Project. ENSR Asia (HK) Ltd. was employed
by CCJV as the Environmental Team to carry out the EM&A programme.
The impact environmental monitoring and audit for the
Project includes the air quality, noise, ecology, landscape and visual
monitoring. The construction of the Project and the EM&A programme
commenced on 1 April 2008.
This report documented the findings of EM&A works
conducted in the period from July 2008 to September 2008. As informed by
the Contractor, construction activities carried out in the reporting quarter
were:
-
Installation
of Soil Nail at Portion A1, Portion A2 and Portion B1;
-
Erection of scaffolded
platform at Portion A2 and B1;
-
Soil nail head preparatory
works at Portion A1; and
-
Erection of working platform
for soil nail installation at Portion C.
Environmental
Monitoring Works
EM&A
Programme
A
summary of monitoring and audit activities conducted in the reporting quarter
is listed below:
|
24-hour TSP monitoring
|
15
|
sessions
|
|
1-hour TSP monitoring
|
48
|
sessions
|
|
Daytime Noise monitoring
|
13
|
sessions
|
|
Ecology monitoring
|
6
|
sessions
|
|
Landscape and Visual Audit
|
7
|
sessions
|
|
Environmental Site Inspection
|
14
|
sessions
|
|
|
|
|
Breaches of Action and Limit
Levels
There was no action / limit level exceedance recorded
for 1-hour and 24-hour TSP monitoring.
In the reporting quarter, all noise level recorded
complied with the limit level.
Complaint, Notification of
Summons and Successful Prosecution
There was no complaint, notification of summons and
successful prosecution received in the reporting quarter.
.
1.
INTRODUCTION
Scope of Report
1.1
This is the second Quarterly Environmental
Monitoring and Audit (EM&A) Summary Report under the Contract CE 28/2004
(GE) – Landslide Preventive Works at Po Shan Road, Mid-Levels – Design and
Construction (Natural Terrain Risk Mitigation Works). This report presented a
summary of the environmental monitoring and audit works, and list of activities
carried out by the ET for the Project for the period from July 2008 to
September 2008.
Project
Organization and Contacts of Key Management
1.2
The project organization is shown in Appendix A.
The key personnel contact names and numbers are summarised in Table 1.1
Table 1.1 Contact Information of Key Personnel
|
Party
|
Position
|
Name
|
Telephone
|
Fax
|
|
CEDD
|
Senior Engineer
|
H. W. Sun
|
2762 5375
|
2714 0247
|
|
ER (MGS)
|
Resident Engineer
|
Andrew J. Westmoreland
|
3188 0400
|
3188 0775
|
|
Assistant Resident Engineer
|
S. F. Chau
|
3188 0400
|
3188 0775
|
|
IEC
(ENVIRON)
|
Independent
Environmental Checker
|
David
Yeung
|
3743
0788
|
3548
6988
|
|
Contractor
(CCJV)
|
Project
Manager
|
Eddie
Tang
|
3188
0538
|
3188
1710
|
|
Safety
and Environmental Officer
|
Ken
Fong
|
3188
0538
|
3188
1710
|
|
ET
(ENSR)
|
ET
Leader
|
Edith
Ng
|
3105
8525
|
2891
0305
|
Summary
of Construction Works
1.3
The Contactor has carried
out major activities in the reporting quarter. Details of the works undertaken
in this reporting period are listed below:
-
Installation
of Soil Nail at Portion A1, Portion A2 and Portion B1;
-
Erection of scaffolded
platform at Portion A2 and B1;
-
Soil nail head preparatory
works at Portion A1; and
-
Erection of working platform
for soil nail installation at Portion C.
1.4
The general layout plan of
the Project site showing the contract area is shown in Figure 1.1.
1.5
The construction programme
is provided in Appendix B.
1.6
The mitigation measures
implementation schedule are presented in Appendix C.
2. ENVIRONMENTAL MONITORING AND AUDIT REQUIREMENTS
Monitoring Parameters
2.1
The
EM&A Manual designated two monitoring stations to monitor environmental
impacts on air quality and noise due to the Project. The monitoring locations
are depicted in Figure 2.1.
2.2
The
EM&A Manual also required ecology monitoring, bi-weekly landscape and
visual audits, and environmental site inspections for air quality, noise, water
quality, chemical, waste management, ecology and landscape and visual.
Environmental Quality Performance Limits (Action/Limit Levels)
2.3
The
environmental quality performance limits (i.e. Action/Limit Levels) were
derived from the baseline air quality monitoring results of Access road to Po Shan Mansions (CA1) and Podium of Hamilton Court (CA2)
and / or as defined in the EM&A Manual (CN1 & CN2), and are given in Appendix D.
Environmental Mitigation Measures
2.4
Relevant
environmental mitigation measures were stipulated in the Particular
Specification and EP (No.: EP-235/2005/B) for the
Contractor to adopt. A list of mitigation measures and their implementation
statuses are given in Appendix C.
3.
MONITORING RESULTS
Air
Quality
3.1
Air quality monitoring,
including 1-hr and 24-hr TSP, was conducted at least 3 times every 7 days and at
least once every 7 days respectively at the 2 monitoring stations (CA1 and
CA2), in accordance with the EM&A Manual. Forty-eight 1-hr TSP and fifteen
24-hr TSP monitoring events were carried out in this reporting quarter.
3.2
The weather was either sunny or
rainy in the reporting quarter. The trend of air quality for the reporting
quarter are given in Appendix E. Major dust source of the construction works
area included soil
nail installation activities from the Project, construction activities of
another project under the same contract (concurrent project) carried out in the
vicinity and nearby traffic emissions.
3.3
There was no Action and Limit
Level exceedance recorded for both 1-hr and 24-hr TSP in the reporting quarter.
3.4
Table 3.1 presents the number of
exceedances recorded in each month of the reporting quarter. The number of
monitoring events included regular monitoring events and additional ones, if
any.
Table 3.1 Summary of Number of Exceedances for 1-hr & 24-hr TSP
Concentration
|
Monitoring Parameter
|
Location
|
Level of Exceedance
|
Month
|
|
Jul 08
|
Aug 08
|
Sep 08
|
|
1-hr TSP
|
CA1
|
No. of monitoring events
|
18
|
15
|
15
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
CA2
|
No. of monitoring events
|
18
|
15
|
15
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
|
Total
|
0
|
0
|
0
|
|
24-hr TSP
|
CA1
|
No. of monitoring events
|
5
|
5
|
5
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
CA2
|
No. of monitoring events
|
5
|
5
|
5
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
|
Total
|
0
|
0
|
0
|
Construction Noise
3.5
Noise monitoring was conducted
at the 2 monitoring stations (CN1 and CN2) for at least once per week during
0700 – 1900 of the reporting quarter. Thirteen noise monitoring events were
conducted in the reporting quarter.
3.6
As no noise complaint was
received in the reporting quarter, no Action Level exceedance was recorded. All
measured noise levels were below the Limit Level and the graphical plots of
trends of the monitoring results are provided in Appendix F.
3.7
Table 3.2 presents the number
of exceedances recorded in each month of the reporting quarter. The number of
monitoring events included regular monitoring events and additional ones, if
any.
Table 3.2 Summary of Number of Exceedances for Daytime Noise
|
Monitoring Parameter
|
Location
|
Level of Exceedance
|
Month
|
|
Jul 08
|
Aug 08
|
Sep 08
|
|
Daytime Noise
|
CN1
|
No. of monitoring events
|
5
|
4
|
4
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
|
Total
|
0
|
0
|
0
|
|
CN2
|
No. of monitoring events
|
5
|
4
|
4
|
|
Action
|
0
|
0
|
0
|
|
Limit
|
0
|
0
|
0
|
|
|
Total
|
0
|
0
|
0
|
3.8
Major noise sources during the noise monitoring included the
construction activities from the Project and another project under the same
contract (concurrent project) carried out in the vicinity and nearby traffic
noise.
Ecology
3.9
Ecological monitoring was
carried out twice a month by a suitably qualified local ecologist to check on
the health and condition of the plant species of conservation interest. Six
ecological monitoring were conducted in the reporting quarter.
3.10
A total of 13 plant species of
conservation interest (i.e. V001 to V013) were identified within the area
during an earlier Detailed Vegetation Survey conducted under this Project. V001 to V013 were found to be in good
condition during the monitoring visits in the reporting period.
3.11
Construction materials such as
planks, sand bags, metal rods were found to be placed over or near the lower
trunks of some trees in Row C, L, O and R.
It was recommended that these materials should be kept in proper place
to avoid damage to vegetation within works area.
3.12
Concrete was found to be
spilled over from the soil nailing works zones onto nearby areas. It was recommended that the concrete should
be removed from the soil surface. The
Contractor advised that the concrete will be removed and measures will be implemented
to avoid any further spillage.
3.13
The leaves, branches and trunk
of a tree (Machilus sp.) located in Row O was found to be covered with sand and
mud probably generated from nearby soil nailing works.
3.14
Two trees, Celtis sinensis and
Machilus sp., located near the conveyor belt and above Row Q were found to be
dead and in very poor condition respectively.
A dead tree (tree tag number T238) was collapsed within works area. It was recommended that all dead trees found
within the construction site should be recorded and reported to relevant
departments without delay.
3.15
Two main roots of a big tree
(Acacia confusa of tree tag number T247) were cut due to the construction of
soil nail number I6 (Figure 4.1).
3.16
The trunk of a tree (tree tag number
T344) located next to a soil nailing area in Row O was covered with concrete.
3.17
Site clearance, soil nailing
and scaffolding works were in progress during the monitoring visits. V042, V043, V048 to 51 and V057 to 59 were
identified with the above works area.
All of them has been fenced off and were in good condition.
3.18
One of the main branches of a
plant (Glochidion wrightii) on Soil Nailing Row X was cut to give way to
machinery. The Contractor was advised
that trimming of plant within works area is not allowed.
3.19
A proper handrail for site
access to the south of Row AF should be set up instead of tying ropes on trees
as support.
3.20
Tree No. T611 (Schefflera
heptaphylla) on Row R was found to be in very poor condition. A recently dead tree on Row AF was tipped to
one side.
3.21
The lower trunk of Tree No.
T5955 adjacent to soil nailing position on Row AF was covered with grout.
3.22
Vegetation located between Row
AO to AU was excessively removed during site clearance. The plant debris was dumped in the adjacent
woodland habitat outside the works area.
Landscape and Visual
3.23
Bi-weekly landscape and visual
audit was conducted by a Registered Landscape Architect (RLA) to monitor the
implementation of landscape and visual mitigation measures. Seven landscape and
visual audits were conducted in the reporting quarter.
3.24
It was still noted that no tree
protection with wooden slats was made for trees enclosed within the drilling
platforms. The Contractor was reminded to
provide adequate tree protection works near the trees in order to prevent
accidentally damaging the trees.
3.25
Construction equipments, metal
pipes / steel bars were observed being placed against the tree trunks of
existing trees at several locations on site.
The Contractor was requested to clear the equipment and construction
materials and not to place them against trees in future in order to prevent
damage to the trees.
3.26
Soil bags were observed placed
on slopes and rested at the base of the tree trunks. The Contractor was requested to clear the
soil bags away from the base of the tree as soon as possible.
3.27
Construction waste pile was
observed on the slope. The Contractor
was requested to clear it away as soon as possible.
3.28
Sealing of the root wounds for tree
T247 was still outstanding. The
Contractor was reminded to apply protective sealant to prevent the roots from
rotting as soon as possible.
3.29
Construction waste was observed
placed at the base of several trees. The
Contractor was requested to clear it away as soon as possible.
3.30
A number of minor tree branches
were observed damaged by typhoon. The Contractor was requested to prune the
broken tree branches back to living tissues as soon as possible.
3.31
A couple of dead trees, including
a tree with rotten trunk at the base were observed near existing tree T534. The
Contractor was recommended to remove all the dead and dying trees away from the
footpath area for the safety of workers.
3.32
Many of the trees numbers were obscured
by recently wrapped hessian tree protection.
The Contractor was requested to re-instate the tree numbers on existing
trees for ease of identification.
3.33
The leaves of existing tree
T611 were wilted due to dry soil condition.
The Contractor was recommended to water the tree on a daily basis and to
monitor the condition of the tree.
3.34
It was observed that the
Contractor had stacked pipe sleeves near the base of the existing tree. The Contractor was requested to remove the pipes
away from the tree as soon as possible.
3.35
It was still observed that the
Contractor had not removed the dead trees, including a tree with rotten trunk
at the base located near existing tree T534.
The Contractor was recommended to remove all the dead and rotten trees
away from the footpath area for safety.
3.36
It was still observed that
rectification of many of the tree identification numbers for the existing
retained trees were outstanding. The Contractor
was reminded to re-instate the tree numbers on existing trees for ease of
reference as soon as possible.
3.37
The leaves of previously wilted
tree T611 had dried out and dying.
3.38
It was observed that the Contractor
had tied the toe board onto the existing tree trunk. The Contractor was requested to remove it as
soon as possible.
Environmental Site Inspection
3.39
There were 14 site inspections
conducted in the reporting quarter to monitor the implementation of proper
environmental pollution control and mitigation measures for the Project. The
major concerns for the Project are air quality, noise, water quality, waste
management, ecology and landscape and visual. Observations recorded are
described below. All the observations were rectified
by the Contractor within the agreed time frame.
Air Quality
3.40
No adverse observation was
identified in the reporting quarter.
Noise
3.41
No adverse observation was
identified in the reporting quarter.
Water Quality
3.42
Debris and leaves were observed
inside the u-channel at Row D and near Row R and Row S. The Contractor was
reminded to clear the u-channel more frequently.
3.43 Minor muddy water was observed running down the u-channel near Row K
and Row M. The Contractor was reminded to clear the exposed earth at all
working platforms and properly maintain the desilting tank next to Row D.
3.44
Exposed earth was observed
around the area of soil nail installation at Row Y and Row AF and on the slope at
Row Y and Row Z. The Contractor was advised to clean up the earth as soon as
the operation was completed.
3.45
Deposited silt was observed
accumulated inside the u-channel at Row R and Row V. The Contractor was
reminded to clear the u-channel more frequently.
3.46
Sand bags at Row R and Row V
were found damaged. The Contractor was advised to replace the sand bags.
Chemical and Waste Management
3.47
Oil drums and soil nail installation controller were found placed on
ground without drip tray at Row C, Row Q, Row R, Row S, Row Y, Row V, Row Z, Row AA
and Row AF. The Contractor was reminded to
provide drip trays to the chemical containers and all plants on site.
3.48
Small amount of cement slurry was
found run off into the u-channel at Row R. The Contractor was reminded to clean
up the slurry inside the u-channel and prevent further runoff.
Ecology
3.49
Sand bags and C&D materials
were observed placed against the trees at Row C, Row D, Row E and Row R. The
Contractor was reminded to keep the C&D materials away from the trees.
3.50
Construction materials placed
near tree trunks and spillage of concrete near soil nailing areas were
observed. Some of the plants were not properly
protected during soil nailing works and serious damages to root systems were
recorded. One recently dead tree was
found within the works area.
3.51
Pruning of tree was observed in
Row X.
3.52
Vegetation located between Row AO
to AU was excessively removed during site clearance.
3.53
The plant debris from site
clearance was dumped in the adjacent woodland habitat outside works area.
Landscape and Visual
3.54
The Contractor was recommended to
provide more protection to existing trees which are surrounded by drilling
platforms and avoid stockpiling of any construction materials / equipments /
sand bags against or near existing trees.
3.55
The Contractor was recommended
to apply root protective sealant to the wounded roots. The Contractor was recommended to seek the
Engineer’s agreement for excavation works near existing tree roots in order to
minimize damage to the tree root system.
If root pruning is required, prior approval from Engineer is required.
3.56
The Contractor was recommended
to clean the material fines off the tree trunks and to provide tree protection
in future when carried out drilling works.
3.57
The Contractor was recommended to
provide treatment to the damaged tree roots to prevent further damage to the
roots.
3.58
The Contractor was recommended
to keep all construction waste and soil bags away from existing trees and to
keep the site clean and tidy.
3.59
The Contractor was recommended to
re-instate all missing tree numbers for existing trees on site for easy
identification.
3.60
The Contractor was recommended
to clear away all dead trees as found on site, including the rotten tree for
safety consideration. The Contractor was
also reminded to record and report all dead trees as found on site to the
Engineer for record.
3.61
The Contractor was recommended
to provide moist hessian wrapping to the exposed cut roots to prevent the roots
from drying out.
3.62
The Contractor was recommended to
clear away all construction materials away from existing trees and not to place
it against or near the trees in future.
3.63
The Contractor was recommended
to remove dead / rotten trees from site for safety.
3.64
The Contractor was recommended to
water the existing tree T611 to help improve the stressed condition of the
tree, and to monitor the tree daily.
3.65
The Contractor was requested to
remove the toe board away from existing tree and not to use tree for anchorage.
3.66
The Contractor was reminded to
rectify all ineligible tree identification numbers for all existing trees.
4.
Advice on Solid and liquid
Waste Mangement Status
4.1
The Contractor has registered as
a chemical waste producer for this Project. The Chemical Waste Storage Area
located at the Contractor’s site office area was properly maintained in the
reporting quarter.
4.2
As advised by the Contractor, 32.08 ton of inert
C&D waste was disposed offsite to Public Filling Barging Point at Quarry
Bay in September 2008. C&D waste generated was reused on site as much as
possible.
5.
Summary of Non-Compliance
(Exceedances) of environmental qualitY
Summary of Exceedances and Review of the Reasons for
non-compliance
5.1
There was no 1-hr TSP, 24-hr
TSP and noise exceedance recorded in the reporting quarter.
6.
Environmental complaints,
notification of summons and successful prosecutioN
6.1
No environmental complaints,
notification of summons and prosecution was received in the reporting quarter.
Table 6.1 summarized the complaint, summons and successful prosecution received
in the reporting period.
Table
6.1 Summary of Environmental Complaints
and Prosecutions
|
|
July 2008
|
August 2008
|
September 2008
|
Total
|
|
Complaint Logged
|
0
|
0
|
0
|
0
|
|
Summons
Served
|
0
|
0
|
0
|
0
|
|
Successful Prosecution
|
0
|
0
|
0
|
0
|
|
Total
|
0
|
0
|
0
|
0
|
7.
Comments, Recommendations and
Conclusions
Comments on Mitigation Measures
7.1
According to the environmental
site inspections performed in the reporting quarter, the following comments are
provided:
Air Quality
-
N/A
Noise
-
N/A
Water Quality
-
Debris, leaves and deposited
silt inside the u-channel should be cleared more frequently.
-
Exposed earth at all working
platforms should be cleared as soon as the soil nailing operation was
completed.
-
The
desilting tank next to Row D should be properly maintained.
-
Damaged sand bags on site
should be replaced.
Chemical and Waste Management
-
All plants and chemical
containers on site should be provided with drip tray.
-
Cement slurry during grouting
works should be prevented from running off into u-channel.
Ecology
-
Hessian sacking should be wrapped around the trunk
of vegetation to prevent damage during the transportation of construction
materials.
-
Pruning of tree branches
should be avoided.
-
Vegetation removal to a
minimum level and clearance should only be conducted in area where necessary.
-
The plant debris from site
clearance should be removed from works area in a timely manner.
-
The spilt grout should be removed
from the tree trunk / root immediately.
-
Proper handrail for site access should be set up
instead of using trees as support.
Landscape and Visual
-
Soil nails on site should
avoid tree trunks and tree roots.
-
More adequate protection should
be provided to existing trees in the work areas and during drilling works.
-
Stockpiling of any
construction materials / equipments / sand bags against or near existing tree
should be avoided.
-
All missing tree numbers
for existing trees on site should be re-instated.
-
All dead trees, including
rotten trees, found on site should be removed for safety concern.
-
Moist hessian wrapping should be provided to the
exposed cut roots to prevent the roots from drying out.
-
All construction materials should be kept away from
existing trees.
-
Trees should not be used to support or anchorage of
any construction material.
-
All ineligible tree identification numbers for all
existing trees should be rectified.
-
All dead trees found on site should be recorded and
reported to the Engineer for record.
Recommendations on EM&A Programme
7.2
The impact air quality and
noise monitoring programme ensured that any environmental impact to the
receivers would be readily detected and timely actions could be taken to
rectify any non-compliance. Assessment
and analysis of monitoring results collected demonstrated the environmental
acceptability of the Project. The ecological
monitoring, bi-weekly landscape and visual audit and weekly site inspection
ensured that all the environmental mitigation measures recommended in the EIA
report were effectively implemented.
7.3
The EM&A programme
effectively monitored the environmental impacts from the construction
activities and no particular recommendation was advised for the improvement of
the programme.
Conclusions
7.4
Air quality and noise
monitoring, ecological monitoring, bi-weekly landscape and visual audit and
weekly site inspection were carried out from July 2008 to September 2008, in
accordance with the EM&A Manual.
7.5
No Action and Limit Level
exceedance or non-compliance was recorded for the monitoring works in the
reporting quarter.
7.6
No environmental complaint, summons
or prosecution was made against the Project in the reporting quarter.
