7.1.1
This section presents the appraisal of the baseline situation for the
land lots within the Study Area due to their past or present land uses history,
which could be a potential of contaminated land issue, and the assessment on
the implications of land contamination associated with both the upgrading of
the Cheung Chau STW and Pak She SPS and the sewers works of the Project.
7.1.2
This assessment has based on the guidelines for evaluation and
assessment of potential contaminated land as stated in Section 3.1 of Annex 19
of the EIAO-TM and has covered the scope outlined in Sections 3.4.5.3 and
3.4.5.4 of the EIA Study Brief.
7.2.1
According to Annex 19 of the EIAO-TM, if a site with historical land
uses which have the potential to cause or have caused land contamination, a
Contamination Assessment Plan (CAP) has to be submitted as part of the EIA
Report to the EPD for endorsement prior to conducting a contamination
assessment of the site. The land
contamination assessment results should be documented in a Contamination
Assessment Report (CAR). If land
contamination is confirmed, a Remediation Action Plan (RAP) should be prepared
and submitted with the CAR as a combined report for EPD approval. Upon the approval of the CAR/RAP, the site
shall be cleaned up the contamination according to the approved RAP prior to
any development or redevelopment of the site.
The preparation of CAP, CAR and RAP shall be prepared in accordance with
the relevant standards and guidelines issued by EPD.
7.2.2
EPD has issued three publications in relation to the land contamination
assessment. They are:
Ÿ
Guidance Note for Contaminated Land Assessment
and Remediation (Guidance Note);
Ÿ
Guidance Manual for use of Risk-based
Remediation Goals (RBRGs) for Contamination Land Management (Guidance Manual);
and
Ÿ
Practice Guide for Investigation and Remediation
of Contaminated Land (Practice Guide).
7.2.3
The Guidance Note for Contaminated Land Assessment and Remediation set
out the requirements for proper assessment and management of potentially
contaminated sites, provide guidelines on how site assessment should be
conducted and suggest practical remedial measures that can be adopted for the
clean-up of a contaminated site.
7.2.4
The Guidance Manual provides the background of the use of RBRGs and
presents instructions for comparison of soil and groundwater data to the
RBRGs.
7.2.5
The Practice Guide outlines the process for conducting land
contamination assessment and remediation in Hong Kong and presents the standard
investigation methods and remediation strategies for the range of potential
contaminated sites and contaminants typically encountered in Hong Kong.
7.3.1
In order to identify land lots / sites within the Study Area that are
potential contaminated sites and evaluate the land contamination impacts, the
following approach was adopted for the land contamination assessment:
Ÿ
Desktop study to review the current and
historical land uses and identify any potential contaminative land uses within
the Study Area; and
Ÿ
Site reconnaissance to identify the existing
land uses and confirm the general environmental conditions associated with each
of the identified sites.
7.3.2
In addition, the following sources of information have been collected
and reviewed:
Ÿ
Aerial photographs from Lands Department taken
between 1924 - 2011;
Ÿ
Acquisition of information related to potential
land contamination from the Environmental Compliance Division of EPD, Fire
Services Department (FSD) and Lands Department (LD); and
Ÿ
Records and photographs from site
reconnaissance.
7.3.3
Potential contaminants and their associated potential hazardous risks
to the land users and surrounding environment would be evaluated with reference
to the EPD’s Guidance Note, Guidance Manual and Practice Guide.
7.4.1
As described in Section 2, the Project includes the upgrading the existing sewers construction
of new sewers for some of village houses, upgrading the existing Pak She SPS
and Cheung Chau STW. The Study Areas
cover Tai Kwai San Tsuen, Cheung Kwai Estate, Round Table 2nd and 3rd Villages,
Lutheran Village, Pak She San Tsuen, Nam She Tong, Fa Peng, Lung Tsai Tsuen, Ko
Shan Tsuen and Tai Shek Hau in Cheung Chau.
These areas are composed of low-rise residential buildings, recreation
facilities and vegetated areas. The
present land uses that give rise to potential concerns for land contamination
include a scrap recycling workshop, shipyards and machinery repairing workshops
for ships along Ping Chong Road and Pak She Praya Road. Figure 7.1 shows the locations of these
potential contaminated sites.
7.5.1
Historical aerial photographs (as listed in Table 7.1) available in the Survey and Mapping Office at Lands Department were reviewed
to identify the potential contaminated sites.
Table 7.1 :
Historical Aerial Photos Reviewed for Cheung Chau
|
Year
|
Height (Feet)
|
Photograph Reference
No.
|
|
1924
|
NA
|
16
|
|
1945
|
2000
|
4161
|
|
1956
|
16700
|
0187
|
|
1963
|
3900
|
4171,
4180
|
|
1968
|
NA
|
953
|
|
1973
|
6000
|
3755
|
|
1977
|
4000
|
18327
|
|
1980
|
5000
|
29188
|
|
1982
|
4000
|
45916
|
|
1984
|
5200
|
57247
|
|
1986
|
2000
|
A04100,
A04101
|
|
1988
|
1000
|
A12493
|
|
1990
|
1000
|
A20328,
A20330
|
|
|
2000
|
A20681
|
|
1992
|
3500
|
A33458,
A33464, A33480
|
|
1996
|
3500
|
A43432
|
|
1998
|
4000
|
A47752
|
|
2000
|
4000
|
A50738
|
|
2002
|
4000
|
CW39820
|
|
2006
|
4000
|
CW72380,
CW73717
|
|
2007
|
6000
|
CS06215,
CS06270
|
|
2008
|
6000
|
CS12301,
CS12495
|
|
2009
|
6000
|
CS26911,
CS27087
|
|
2010
|
6000
|
RS01455,
RS05125
|
|
2011
|
3000
|
CW89340,
CW89559
|
7.5.2
The review of available historical aerial photographs indicates that
Cheung Chau consists of mainly village houses and vegetation areas. The oldest aerial photograph for Cheung Chau
was taken in 1924. It shows that there
were residential houses along the areas of Tung Wan and Cheung Chau Wan. The present area of Cheung Kwai Estate
located north of Cheung Chau Wan was green land in the 1924 aerial
photograph. The existing machinery
repairing workshops for ships, shipyards, scrap recycling workshop and Cheung
Chau STW sites were not reclaimed at the time.
Since 1970’s, village houses began to increase on the island. In the 1980’s, reclamation works began at the
exiting machinery repairing workshops area and along the southern coastline of
Cheung Chau Wan. Cheung Kwai Estate and
a few shipyards along Ping Chong Road were found in the 1984 aerial
photograph. In the 1990 aerial
photograph, it was found that there were more shipyards and machinery repairing
workshops for ships along Ping Chong Road.
The scrap recycling workshop along Ping Chong Road was also observed in
the 1990 aerial photograph. Figures 7.2 to 7.8 show the aerial photographs of 1924,
1977, 1980, 1984, 1990, 1996 and 2011 for Cheung Chau.
7.6.1
Information regarding historical records of chemical spillage,
violations of environmental regulations and licences / permits was requested
from the FSD and the Regional Office (South) of EPD for a review. The correspondences are provided in Appendix 7.1.
7.6.2
Table
7.2 lists the chemical waste producers registered under the Waste Disposal
(Chemical Waste) (General) Regulation within the vicinity of the Project.
Table
7.2 :
Records of Registration of Chemical Waste Producer
|
Name
of Registered Waste Producers
|
Address
|
Business
Type
|
|
Chung
Shak Hei (C.C) Home for the Aged Ltd.
|
Pak
She, Cheung Chau, HK
|
Elderly
Service
|
|
Cheung
Chau Government Secondary School
|
5B
School Road, Outlying Island, NT
|
Education
|
|
Hop Lee Construction Company
- Kam Kong Primary School
|
Cheung Chau Church Kam
Kong Primary School, 1 Peak Road West, Outlying Island, N.T.
|
Construction
|
|
ST John Hospital -
Dispensary/Pathology Laboratory/ X-Ray Department
|
Hospital Road, Cheung
Chau, NT
|
Hospital
|
|
Fire Services
Department
|
Cheung Chau Fire
Station, 1 Ping Chong Road, Cheung Chau
|
Fire Station
|
|
Water Supplies
Department
|
Tai Kwai Wan San Tsuen,
N.T.
|
Provision of water
supplies and attendant services
|
|
Buddhist Wai Yan
Memorial College
|
Buddhist Wai Yan
Memorial College, 25 Tai Hing Tai Road, Outlying Island, NT
|
Education
|
7.6.3
According to the information provided by EPD, there is no record of
chemical spillage in the past within the Study Area.
7.6.4
Table
7.3 lists dangerous goods stores within the Study Area.
Table 7.3 :
Records of Registration of Dangerous Goods Stores
|
Location of Registrant
|
Type of Dangerous Goods
|
Method of Storage
|
|
Shek Kau Chau
|
Diesel
|
Licensed dangerous goods
Store on G/F
|
|
Cheung Chau Hospital Road
|
Oxygen cylinders
|
Licensed dangerous goods
store on G/F
|
7.6.5
According to the information provided by FSD, there is no record for
spillage or leakage of dangerous goods at the above listed dangerous good
stores.
7.7.1
Construction workers may be exposed to contaminated soils during the
construction stage. The main exposure
routes for construction workers are accidental direct ingestion of contaminated
soils through poor hygiene and eating, or through direct contact with
contaminants during excavation works.
7.7.2
During the operational phase of the Project, the maintenance workers
for the sewerage system are the sensitive receivers.
7.8.1
The site reconnaissance was undertaken on 28 October 2011. Based on site observations, the majority of the
proposed sewers works are along public and vehicular access roads. There were no potential contaminated sites
identified within the proposed construction areas of sewers and Cheung Chau
STW. However, there are machinery
repairing workshops for ships and scrap recycling workshop in the vicinity of
the Pak She SPS. Access to these
potential contaminated sites could not be granted and observations were made
outside the sites. It was found that the
potential contaminated sites are paved with concrete. Oil stains next to the oil drums were
observed at some of the potential contaminated sites. As the upgrading Pak She SPS would not
involve any excavation works within the contaminated sites, the construction
workers would not have a direct contact of the potential contaminated
soils. Therefore, no potential land
contamination impacts are anticipated and no further site investigation is
required.
7.8.2
Both Cheung Chau STW and Pak She SPS were built on a reclaimed land and
operation in the mid 1980’s (Figure 7.5). Power supplier has been provided for Cheung
Chau STW and Pak She SPS and no fuel, chemical or dangerous goods is used for
its operation. Therefore, no
contaminated soils underneath Cheung Chau STW and Pak She SPS sites are
anticipated.
7.8.3
The details of the current and historical land uses of the potential
contaminated areas are summarized in Table
7.4.
Table 7.4 :
Potentially Contaminated Sites Identified in the Vicinity of the Project Area
|
Location
|
Current Land Use
|
Historical Land Use
|
Potential Contamination Impact on the
Project Area
|
Need for Further Site Investigation
|
|
Pak She Praya Road and Ping Chong Road
|
Machinery repairing workshops and a
scrap recycling workshop
|
The site is a reclaimed land and
appears to be machinery repairing workshops and a scrap recycling workshop
since 1990.
|
Oil stains next to oil drums were
observed on the concrete paved area for some of the workshops.
The upgrading of Pak She SPS would not
involve excavation works within the contaminated site. Therefore, the construction workers would
not have direct contact with the potential contaminated soils.
|
No
|
7.8.4
The operation of the upgraded Cheung Chau STW, Pak She SPS and existing
sewers would not cause land contamination.
Therefore, there would be no land contamination impacts on the
maintenance workers for the sewerage system.
7.9.1
No potential land contamination sites are located within the
construction areas of the proposed upgrading works and sewer alignment, the
upgraded Cheung Chau STW and Pak She SPS.
No unacceptable residual impact is anticipated during the construction
and operation of the Project.
7.10.1
There are no EM&A requirements for land contamination.
7.11.1
The land contamination assessment was undertaken by reviewing
historical and current land uses and site reconnaissance. Based on the findings of the site appraisal,
there were potential contaminated sites at the Shipyard and the Machinery
Repairing and Recycling Workshops for Ship.
However, as there are no excavation works within the contaminated sites,
no potential contaminated soils would be disturbed. The unacceptable impacts of land
contamination are not expected during the construction phase of the
Project.
7.11.2
The operation of the Project is not potential contaminated land
use. No operational contamination
impacts are anticipated.