11. Land Contamination

11.1 Background

11.1.1.1 The objectives of this section are to summarise the findings of the land contamination assessment which includes a desktop review of the existing information related to the development, findings of the site investigation (SI) works, interpretation of the extent of land contamination based on the findings, recommendation of any necessary remediation action and the way forward on detailed site investigations to ascertain the extent of land contamination. Section 3.4.5 of the EIA Study Brief No: ESB-188/2008 specified that a land contamination assessment shall be undertaken and that a Contamination Assessment Plan (CAP), Contamination Assessment Report (CAR) and Remediation Action Plan (RAP) (if confirmed necessary) shall be endorsed by the EPD. These documents, including a Supplementary CAP addressing the potential land contamination issues due to the addition of works sites and works areas for the KTE project, are included in Appendices 11.1 and 11.2 of this EIA report.

11.2 Environmental Standards and Criteria

11.2.1.1 Relevant legislation to the land contamination issues as a result of handling, treatment and disposal of contaminated materials are as follows:

· Environmental Impact Assessment Ordinance (Cap 499);

· Waste Disposal Ordinance (Cap 354);

· Waste Disposal (Chemical Waste) (General) Regulation (Cap 354C); and

· Code of Practice of the Packaging, Labelling and Storage of Chemical Waste, EPD (1992).

11.2.1.2 The following EPD publications also provide guidance on the land contamination assessment relevant to this study:

· Guidance Note for Contaminated Land Assessment and Remediation;

· Guidance Manual for Use of Risk-Based Remediation Goals (RBRGs) for Contaminated Land Management; and

· Guidance Notes for Investigation Remediation of Contaminated Sites of Petrol Filling Stations, Boatyards, and Car Repair/Dismantling Workshops.

11.3 Assessment Methodology

11.3.1.1 The contaminated land assessment methodology comprises the following key survey tasks in order to identify and evaluate the potential of land contamination within the study area:

(a) A desktop review to appraise the current and historical land uses within the study area in connection with land uses and potential activities leading to land contamination with the aid of aerial photographs, survey maps and the geological map as have been addressed in the endorsed CAP and supplementary CAP;

(b) A site reconnaissance to identify any visual contamination hotspots, as have been addressed in the endorsed CAP and supplementary CAP;

(c) Definition of field sampling and laboratory testing regimes and supervision of the field and laboratory testing works based on the Risk-Based Remediation Goals (RBRGs) promulgated since August 2007 in Hong Kong, if contaminated land hotspots were identified;

(d) Interpretation and assessment of the findings of the site investigation (if required) for soil and groundwater samples following the philosophy of the RBRGs which estimate the extent of remediation required to the level of risk under certain land uses for the protection of human health; and

(e) Recommendation of any necessary contamination remediation works for the future KTE operation based on the conclusion of the land contamination assessment.

11.3.1.2 The proposed construction scheme for the tunnel from YMT to WHA comprises the construction of access shafts followed by drill-and-blast and mechanical breaking along the alignment, and excavated materials will be mucked out at designated locations near the potentially contaminated sites. As such, excavation workers at these locations would be potentially prone to the risk of land contamination impact.

11.3.1.3 Soil bore logs with the description of sub-soil strata were prepared for all sampling locations. All sampling equipment and apparatus were thoroughly cleaned and decontaminated before and after drilling and sampling at each sampling location. All necessary measures will be provided to comply with statutory requirements in respect of environmental, health and safety aspects.

11.3.1.4 Details of the methodology for the field sampling and laboratory analyses in the SI are provided in the endorsed CAP in Appendix 11.1. The results of the laboratory analyses were interpreted in accordance with the Guidance Note for Contaminated Land Assessment and Remediation, and Guidance Manual for Use of Risk-Based Remediation Goals for Contaminated Land Management. Reference was made to the RBRG criteria for assessing the degree of land contamination in the site based on the proposed future land use as tabulated in Tables 11.1 and 11.2.

Table 11.1: Risk-Based Remediation Goals for Soil and Soil Saturation Limit

Chemical	Risk-Based Remediation Goals for Soil			Soil Saturation Limit (Csat) (mg/kg)
Chemical	Urban Residential (mg/kg)	Industrial (mg/kg)	Public Parks (mg/kg)	Soil Saturation Limit (Csat) (mg/kg)
VOCs
Benzene	7.04E-01	3.21E+00	4.22E+01	3.36E+02
Ethylbenzene	7.09E+02	8.24E+03	1.00E+04*	1.38E+02
Toluene	1.44E+03	1.00E+04*	1.00E+04*	2.35E+02
Xylenes (Total)	9.50E+01	1.23E+03	1.00E+04*	1.50E+02
SVOCs
Acenaphthene	3.51E+03	1.00E+04*	1.00E+04*	6.02E+01
Acenaphthylene	2.34E+03	1.00E+04*	1.00E+04*	1.98E+01
Anthracene	1.00E+04*	1.00E+04*	1.00E+04*	2.56E+00
Benzo(a)anthracene	1.20E+01	9.18E+01	3.83E+01	-
Benzo(a)pyrene	1.20E+00	9.18E+00	3.83E+00	-
Benzo(b)fluoranthene	9.88E+00	1.78E+01	2.04E+01	-
Benzo(g,h,i)perylene	1.80E+03	1.00E+04*	5.74E+03	-
Benzo(k)fluoranthene	1.20E+02	9.18E+02	3.83E+02	-
Chrysene	8.71E+02	1.14E+03	1.54E+03	-
Dibenzo(a,h)anthracene	1.20E+00	9.18E+00	3.83E+00	-
Fluoranthene	2.40E+03	1.00E+04*	7.62E+03	-
Fluorene	2.38E+03	1.00E+04*	7.45E+03	5.47E+01
Indeno(1,2,3-cd)pyrene	1.20E+01	9.18E+01	3.83E+01	-
Naphthalene	1.82E+02	4.53E+02	9.14E+02	1.25E+02
Phenanthrene	1.00E+04*	1.00E+04*	1.00E+04*	2.80E+01
Pyrene	1.80E+03	1.00E+04*	5.72E+03	-
Metals
Antimony	2.95E+01	2.61E+02	9.79E+01	-
Arsenic	2.21E+01	1.96E+02	7.35E+01	-
Barium	1.00E+04*	1.00E+04*	1.00E+04*	-
Cadmium	7.38E+01	6.53E+02	2.45E+02	-
Chromium III	1.00E+04*	1.00E+04*	1.00E+04*	-
Chromium VI	2.21E+02	2.18E+02	7.35E+02	-
Cobalt	1.48E+03	1.00E+04*	4.90E+03	-
Copper	2.95E+03	1.00E+04*	9.79E+03	-
Lead	2.58E+02	2.29E+03	8.57E+02	-
Manganese	1.00E+04*	1.00E+04*	1.00E+04*	-
Mercury	1.10E+01	3.84E+01	4.56E+01	-
Molybdenum	3.69E+02	3.26E+03	1.22E+03	-
Nickel	1.48E+03	1.00E+04*	4.90E+03	-
Tin	1.00E+04*	1.00E+04*	1.00E+04*	-
Zinc	1.00E+04*	1.00E+04*	1.00E+04*	-
Dioxins/PCBs
PCBs	2.36E-01	7.48E-01	7.56E-01	-
Petroleum Carbon Ranges
C6 - C8	1.41E+03	1.00E+04*	1.00E+04*	1.00E+03
C9 - C16	2.24E+03	1.00E+04*	1.00E+04*	3.00E+03
C17 - C35	1.00E+04*	1.00E+04*	1.00E+04*	5.00E+03
Other Inorganic Compounds
Cyanide, free	1.48E+03	1.00E+04*	4.90E+03	-
Organometallics
TBTO	2.21E+01	1.96E+02	7.35E+01	-

Soil saturation limits for petroleum carbon ranges taken from the Canada-Wide Standards for Petroleum Hydrocarbons in Soil, CCME 2000; * denotes a ‘ceiling limit’ concentration.

Table 11.2: Risk-Based Remediation Goals for Groundwater and Solubility Limit

Chemical	Risk-Based Remediation Goals for Groundwater:		Solubility Limit (mg/L)
Chemical	Urban Residential (mg/L)	Industrial (mg/L)	Solubility Limit (mg/L)
VOCs
Benzene	3.86E+00	5.40E+01	1.75E+03
Ethylbenzene	1.02E+03	1.00E+04*	1.69E+02
Toluene	5.11E+03	1.00E+04*	5.26E+02
Xylenes (Total)	1.12E+02	1.57E+03	1.75E+02
SVOCs
Acenaphthene	1.00E+04*	1.00E+04*	4.24E+00
Acenaphthylene	1.41E+03	1.00E+04*	3.93E+00
Anthracene	1.00E+04*	1.00E+04*	4.34E-02
Benzo(a)anthracene	-	-	-
Benzo(a)pyrene	-	-	-
Benzo(b)fluoranthene	5.39E-01	7.53E+00	1.50E-03
Benzo(g,h,i)perylene	-	-	-
Benzo(k)fluoranthene	-	-	-
Chrysene	5.81E+01	8.12E+02	1.60E-03
Dibenzo(a,h)anthracene	-	-	-
Fluoranthene	1.00E+04*	1.00E+04*	2.06E-01
Fluorene	1.00E+04*	1.00E+04*	1.98E+00
Indeno(1,2,3-cd)pyrene	-	-	-
Naphthalene	6.17E+01	8.62E+02	3.10E+01
Phenanthrene	1.00E+04*	1.00E+04*	1.00E+00
Pyrene	1.00E+04*	1.00E+04*	1.35E-01
Metals
Antimony	-	-	-
Arsenic	-	-	-
Barium	-	-	-
Cadmium	-	-	-
Chromium III	-	-	-
Chromium VI	-	-	-
Cobalt	-	-	-
Copper	-	-	-
Lead	-	-	-
Manganese	-	-	-
Mercury	4.86E-01	6.79E+00	-
Molybdenum	-	-	-
Nickel	-	-	-
Tin	-	-	-
Zinc	-	-	-
Dioxins/PCBs
PCBs	4.33E-01	5.11E+00	3.10E-02
Petroleum Carbon Ranges
C6 - C8	8.22E+01	1.15E+03	5.23E+00
C9 - C16	7.14E+02	9.98E+03	2.80E+00
C17 - C35	1.28E+01	1.78E+02	2.80E+00
Other Inorganic Compounds
Cyanide, free	-	-	-
Organometallics
TBTO	-	-	-

- denotes that RBRG could not be calculated because the toxicity or physical/chemical values were unavailable, or the condition of Henry’s Law Constant>1.00E-05 was not met for the inhalation pathway;

* denotes a ‘ceiling limit’ concentration;

Water solubilities for Petroleum Carbon Range aliphatic C9-C16 and greater than C16 generally are considered to be effectively zero and therefore the aromatic solubility for C9-C16 is used.

11.4 Identification of Potential Impacts

11.4.1 Identification of Contamination Sources

11.4.1.1 Based on the initial site appraisal, reconnaissance site visit, review of previous SI and other relevant information as summarised in the endorsed CAP (Appendix 11.1), the potential sources of land contamination relevant to the KTE development have been identified. The contaminants of concern (COCs) for the site have been selected based on the historical land use information collected during the above initial site appraisal with reference to the Guidance Note for Contaminated Land Assessment and Remediation, Guidance Manual for Use of Risk-Based Remediation Goals for Contaminated Land Management. With respect to the historic land use information, the broad groups of selected COCs for this investigation include volatile organic compounds (BTEX: Benzene, Toluene, Ethylbenzene, Xylene), semi-volatile organic compounds (PAHs: Polycyclic Aromatic Hydrocarbons), metals, petroleum hydrocarbon, PCBs, cyanide, and organometallic compound (TBTO: Tributyltin Oxide).

11.4.2 Identification of Sensitive Receivers

11.4.2.1 Construction workers would be prone to exposure to any potential contaminated materials during the construction phase during excavation of the identified contaminated sites. The principle exposure routes would include:

· Direct ingestion of contaminated materials through eating or drinking on-site; and

· Dermal contact with contaminated materials.

11.4.2.2 There would be no sensitive receivers during the operational phase of the KTE project provided that remediation action and measures have been fully implemented. Potential environmental impacts could, also, arise from any remediation works, if required (e.g. air emissions and water discharges, etc), that may affect the surrounding sensitive receivers e.g. human receivers and water bodies. Proper mitigation measures should, therefore, be implemented as necessary.

11.4.3 Conceptual Site Model and Site Investigation

11.4.3.1 The conceptual site model is summarised in Table 11.3 below and based on this, the sampling locations were devised as shown in Table 11.4 and Figures 11.1 and 11.2.

11.4.3.2 As stated in the endorsed CAP, the historic and existing landuse and geological information suggest that the operation of Concord kerosene store would be a potential hotspot of land contamination, as its location would interface with the footprint of the mucking out point of HOM Station and the future entrance at Chung Hau Street. As there are 3 underground kerosene tanks within these premises, it is recommended that when the permission for access is granted at the time when the land is resumed, a reconnaissance site visit should be carried out and a review undertaken of whether further SI would be required. In accordance with Clause 3.4.5.6 of the EIA Study Brief, if there is potential contaminated site which is inaccessible for preparing sampling and analysis during the course of the EIA study, e.g. due to site access problem, the information summarised in Table 11.5 were provided.

11.5 Prediction of Environmental Impacts

11.5.1 Potential Soil Contamination

11.5.1.1 A total of 19 soil samples were collected from 4 boreholes at BH1, BH2, BH3 and BH4 and 1 trial pit at TP1, as shown in Figures 11.1 and 11.2.

11.5.1.2 A summary of laboratory testing results and the laboratory reports are included in the CAR in Appendix 11.2. For the soil samples collected, antimony, cadmium, chromium VI and mercury were mostly determined to be below the reporting limits of the laboratory, whilst arsenic, chromium III, copper, molybdenum, nickel, tin and zinc also exhibited low levels. Although the concentrations of barium, cobalt, lead and manganese for soil samples collected at 1.5m and 3.0m at TP1 showed elevated levels, all of them comply with the RBRGs for “Industrial” landuse where the railway inside HOM and WHA Stations would be located. The concentrations of petroleum hydrocarbon, VOCs, SVOC, PCBs, cyanide and TBTO were all below the reporting limits of the laboratory. There were no exceedances of the RBRGs determined for all the soil samples collected in the SI.

Table 11.3: Conceptual Site Model of KTE Project

Potential Sources of Contamination	Potential Human Receptors	Potential Pathways	Preliminary Appraisal of Potential Impact
*Tunnels from YMT to HOM*
Esso filling station and LPG store at Princess Margaret Road, Ho Man Tin next to the Society for the Prevention of Cruelty to Animals, and possible spillage and/or leakage of fuel from underground storage tanks, past landuse and operation	Construction Phase: Construction workers inside the tunnels	The tunnels would be situated deep in rock with no major fault lines identified and physically separated from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
	Operational Phase: Passengers and staff of KTE project	The tunnels would be situated deep in rock with no major fault lines identified and physically separated from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
*HOM Station*
Concord kerosene store at No.33, Chung Hau Street, Ho Man Tin, and possible spillage and/or leakage of kerosene from past landuse and operation (from the identified decommissioned underground kerosene storage tank)	Construction Phase: Construction workers for construction of the station entrance at Chung Hau Street.	Rock nature of site geology and existence of concrete floor of the premises, but uncertain for any other pathways inside the premises leading to spillage and leakage, hence migration of contaminants uncertain, due to restriction of site access	Potential contamination anticipated. There are 3 kerosene storage tanks beneath the building of the kerosene store. Also, the owner would be unlikely to permit any proposed GI works to be undertaken within their premises, especially near or underneath the 3 kerosene tanks. Also, the inspection and identification of any hotspots at the kerosene filling area was not permitted by the owner. As such, a borehole was proposed on the existing slope adjacent to the storage tanks. It is suggested that a reconnaissance site visit should be carried out upon the resumption of the land area when the STT KX1484 land lease expired after 2010 to review whether further SI would be required (details refer to Table 11.5 below).
Concord kerosene store at No.33, Chung Hau Street, Ho Man Tin, and possible spillage and/or leakage of kerosene from past landuse and operation (from the identified decommissioned underground kerosene storage tank)	Operational Phase: Passengers and staff using the station Entrances B1 and B2 and adits	The above ground station entrance and adit would be physically separated from any potential underground contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
Esso filling station at No.157-171, Wuhu Street, Hung Hom (from the underground storage tanks), and the nearby vehicle repairing garages	Construction Phase: Workers for the construction of the access shaft at Wuhu Street Temporary Playground and HOM Station Entrance C2	The station entrance would be physically separated at long distance (>40m) from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Unlikely at the access shaft, as the potential pathway would be too long for the direct and indirect exposure of human receptors to the possible source of contaminants
	Operational Phase: Passengers and staff using the station Entrance C2	The station entrance would be physically separated at long distance (>40m) from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Unlikely at the access shaft, as the potential pathway would be too long for the direct and indirect exposure of human receptors to the possible source of contaminants
*Tunnels from HOM to WHA*
Esso filling station at No.157-171, Wuhu Street, Hung Hom (from the underground storage tanks), and the nearby vehicle repairing garages	Construction Phase: Construction workers inside the tunnels	The tunnels would be situated beneath the rock head with no major fault lines identified and physically separated from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
	Operational Phase: Passengers and staff of KTE project	The tunnels would be situated beneath the rock head with no major fault lines identified and physically separated from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
Historic operation of dockyards at the existing Tak On Street along the KTE alignment, and possible contamination due to previous landuse e.g. metal workshop, ship repairing, etc	Construction Phase: Construction workers inside the tunnels	The construction works would be physically separated at long distance (~100m) from any potential contamination sources, hence unlikely forming pathways for migration of contaminants	Unlikely, as the potential pathway would be too long for the direct and indirect exposure of human receptors to the possible source of contaminants
	Operational Phase: Passengers and staff of KTE project	The tunnels would be physically separated from any potential underground contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants
*WHA Station*
Historic operation of dockyards at the southern side of Tak On Street to the proposed WHA Station, and possible contamination due to previous landuse, e.g. metal workshop, ship repairing, etc	Construction Phase: Workers for the construction of station entrance and adits at the southern side of WHA Station to be built along Hung Hom Road and Shung King Street	Potential direct and indirect contacts with contaminants in soil and/or groundwater	Potential contamination anticipated, as direct and indirect pathways for the exposure of human receptors to the possible source of contaminants exist
	Operation Phase: Passengers and staff using the station entrance and adit to be built at that location	The above ground station entrance and underground adits would be physically separated from any potential underground contamination sources, hence unlikely forming pathways for migration of contaminants	Not anticipated, as no direct/indirect pathways for the exposure of human receptors to the possible source of contaminants

Table 11.4: Details of Sampling Locations

ID	Type of Investigation	Location	Characteristics
BH1	Borehole	Existing slope beneath Concord kerosene store at Chung Hau Street	Potential contamination of soil and groundwater due to the historic operation of the kerosene store
TP1	Trial Pit
BH2	Borehole	Existing pedestrian parts of Hung Hom Road at Whampoa Estate adjacent to Ka Fu Building.	Potential contamination of soil and groundwater due to the historic landuse, e.g. metal workshop, ship repairing, etc
BH3	Borehole	Existing pedestrian area at Shung King Street adjacent to The Whampoa (the ship).	Potential contamination of soil and groundwater due to the historic landuse, e.g. metal workshop, ship repairing, etc
BH4	Borehole	Existing pedestrian area at the junction of Tak On Street and Tak Ting Street at Whampoa Garden.	Potential contamination of soil and groundwater due to the historic landuse, e.g. metal workshop, ship repairing, etc

Table 11.5: Information for Contamination Assessment at Concord Kerosene Store at Chung Hau Street

Stage	Details
1.Review of Available Information	Historic and existing landuse and geological information reviewed in the endorsed CAP suggest that the operation of the Concord kerosene store would be a potential hotspot of land contamination. The kerosene store is under a Short Term Tenancy land lease (STT KX1484) which will be expired in 2010. According to a representative of Concord Oil (Hong Kong) Limited, there are 3 underground kerosene tanks in the premises for supplying kerosene to their domestic and industrial customers. The tanks, enclosed in concrete walls, were installed in series on a rock platform adjacent to the slope and at the basement of the building structure inside the kerosene store (2 floors beneath the ground level from Chung Hau Street). There was continuous operation of these kerosene supply, but the last refilling occurred in around end of 2008 to early 2009 and no further refilling of the tanks has been made since then. However, the representative of Concord Oil (Hong Kong) Limited advised that, due to their safety concern including their vicinity to the slope along Chung Hau Street and the structural stability of their building, they would not permit any proposed GI works within their premises to be undertaken, especially near or underneath the 3 underground kerosene tanks.
2.Initial Contamination Evaluation and Possible Remediation Method	According to the Fire Services Department (refer to Appendix 5.4 of the endorsed CAP), there was no record of spillage incidents reported at this kerosene store. A sampling point at BH1, which was carried out in accordance to the endorsed CAP, has also revealed that there was no contamination and hence any potential migration of contaminant would be unlikely. Nevertheless, as stated in the endorsed CAP, the historic and existing landuse and geological information reviewed suggest that the operation of Concord kerosene store would be a potential hotspot of land contamination.
3.Confirmation of whether the contamination problem at this site would be surmountable	Based on the available information in the desktop review of the existing Concord kerosene store, if land contamination were discovered, it would be unlikely that the contamination would be insurmountable and that the methods for the remediation of oil contaminated sites as recommended in the above Guidance Notes for Investigation and Remediation of Contaminated Sites of Petrol Filling Stations, Boat Yards, and Car Repair/Dismantling Workshops would be applicable, e.g. biopiling, etc. It is recommended that when the permission for access is granted when the land is resumed, a reconnaissance site visit should be carried out to review whether contamination hotspots could be identified in the premises and hence whether further SI would be required.
4.Sampling and Analysis Proposal	Upon the completion of the reconnaissance site visit, if further SI would be required, the approach to sampling and analysis would follow the requirements of the EPD’s Guidance Notes for Investigation Remediation of Contaminated Sites of Petrol Filling Stations, Boatyards, and Car Repair/Dismantling Workshops.
5.Schedule of Submissions	If further land contamination SI would be required, the following schedule of submissions to the EPD for endorsement is anticipated: · Supplementary CAP – approximately 1 month upon the completion of the reconnaissance site visit; · Supplementary CAR (and RAP if contamination is confirmed) – approximately 6 months upon endorsement of the supplementary CAP by the EPD as well as successful granting of site access for the land contamination SI; and · Remediation Report – to be confirmed in the Supplementary CAR.

11.5.2 Potential Groundwater Contamination

11.5.2.1 One groundwater sample was collected at each of BH2 and BH3. A summary of laboratory testing results and the laboratory reports are included in the CAR in Appendix 11.2. It should be noted that no groundwater was encountered at BH1, TP1 and BH4. All of the tested COCs in the groundwater sample were below the reporting limits of the laboratory or at very low levels, and there was no exceedance of the RBRGs.

11.6 Conclusions

11.6.1.1 There were no exceedances of the RBRGs determined for any of the soil and groundwater samples collected in the SI.

11.6.1.2 In addition, as the operation of Concord kerosene store would be a potential hotspot of land contamination, it is recommended that when the permission for access is granted at the time when the land is resumed, a reconnaissance site visit should be carried out to review whether further SI would be required. In accordance with Clause 3.4.5.6 of the EIA Study Brief, if there is potential contaminated site which is inaccessible for preparing sampling and analysis during the course of the EIA study, e.g. due to site access problem, the information summarised in Table 11.5 were provided.