7 land contamination

7.1 Introduction

7.1.1 This section reviews the potential environmental issues associated with land contamination and assesses the implications of land contamination for the proposed land uses at the site in accordance with the EIA Study Brief Clause 6.5.11.

7.2 Environmental Legislation, Policies, Plans, Standards and Criteria

7.2.1 The Practice Note for Professional Persons ProPECC PN3/94 “Contaminated Land Assessment and Remediation” and “Guidance Notes for Investigation and Remediation of Contaminated Sites of: Petrol Filling Stations, Boatyards, and Car Repair / Dismantling Workshops” issued by the Environmental Protection Department (EPD) provide guidance on land contamination assessment. This note makes reference to criteria developed in the Netherlands, which are most comprehensive and widely used for contaminated site assessment. There are currently no standards for the clean-up of contaminated soil and groundwater in Hong Kong. However, the Dutch guidelines are generally referenced as the criteria for assessing soil and groundwater contamination.

7.2.2 Provisions for consideration of contamination issues are given in the Section 3 “Potential Contaminated Land Issues” of Annex 19 “Guidelines for Assessment of Impact on Sites of Cultural Heritage and Other Impacts” of the Technical Memorandum on Environmental Impact Assessment Process (EIAO-TM).

7.3 Existing Land Contamination Condition

7.3.1 Preliminary information reveals that there are several potential contaminating land uses within the Study Area:

· A King Marine, an existing shipyard, is located at the eastern part of the development area;

· Royal Hong Kong Yacht Club (RHKYC) is located at the central part of the development area;

· Wan Chai West Preliminary Treatment Works (PTW), a preliminary sewage treatment works, is located at Lung King Street;

· Wan Chai East PTW, a preliminary sewage treatment works, is located between Hung Hing Road and Wan Shing Street; and

· some car repairing workshops are located along the segment between Luard Road and Fleming Road of Jaffe Road.

7.3.2 It is anticipated that only limited chemicals are used at these preliminary sewage treatment works and any chemical waste generated would be handled and disposed of properly by Government officials. In addition, the car workshops are located more than 100 m away from the site boundary of WDII. However, the proposed construction works for the elevated section of the trunk road would be carried out to the southern part of the RHKYC. As such, the concern of the land contamination assessment would be on A King Marine and the RHKYC.

7.4 Identification of Sensitive Receivers

7.4.1 Compared to the future users of the land within the Study Area, construction workers are more likely to be exposed to any potential contaminated material during excavation and preparation of foundation works. Depending on the nature of the contaminants, hazard during preparation of foundations and subsurface services may be significant. The principal exposure routes for workers include:

· direct ingestion of contaminated soils through eating, drinking or smoking on site; and

· dermal contact with contaminated spoil.

7.4.2 Groundwater contamination, if severe, can be regarded as a source of marine water pollution in coastal areas as a result of percolation and infiltration.

7.5 Description of the Environment

A King Marine

7.5.1 The following background information has been reviewed for the environmental setting and historical uses of the subject shipyard:

· Aerial photographs from Causeway Bay (1968, 32259 of 5.11.80, A20665 of 19.3.90, A36934 of 5.12.93, CN12608 of 7.12.95, and A50906 of 3.2.00); and

· Sheet 11 of the Geotechnical Control Office Series HGM 20, Solid and Superficial Geology Map (Edition 1, 1986).

7.5.2 The review of relevant historical aerial photographs indicated that full-scale shipyard operation has been commenced before 1968. However, the scale of operation has been gradually diminished and eventually business operation at the east portion of the site ceased in 1994 for the provision of fire station.

7.5.3 The review of the Solid and Superficial Geology Map indicates that the land within the subject shipyard is comprised of marine sand overlain by fill and sanitary fill.

The Royal Hong Kong Yacht Club

7.5.4 The following background information has been reviewed for the environmental setting and historical uses of the subject yacht club:

· Aerial photographs from Causeway Bay (7222 of 1963, 2381 of 1969, 29775 of 1980, A20669 of 1990 and CN26290 of 2000); and

· Sheet 11 of the Geotechnical Control Office Series HGM 20, Solid and Superficial Geology Map (Edition 1, 1986).

7.5.5 The review of relevant historical aerial photographs indicated that full-scale yacht club has been commenced before 1963. With the construction of Cross Harbour Tunnel at the 1969, the waterfront was shaped to the recent landscape. After the construction of the breakwater at the northern side of Kellett Island and the swimming pool of the yacht club (completed at 1990), no further change is found afterwards.

7.5.6 The review of the Solid and Superficial Geology Map indicates that the land within the subject yacht club is comprised of marine sand overlain by fill and sanitary fill.

7.6 Assessment Methodology

7.6.1 The assessment methodology was developed in accordance with the Practice Note ProPECC PN3/94 “Contaminated Land Assessment and Remediation” and “Guidance Notes for Investigation and Remediation of Contamination Sites of: Petrol Filling Stations, Boatyards, and Car Repair / Dismantling Workshops” issued by EPD.

Environmental Information Review

7.6.2 Specific information, that is, historical records of chemical spillage and any violations of environmental regulations, have been requested from the Fire Services Department (FSD) and the Local Control Office (LCO) of Environmental Protection Department (EPD).

7.6.3 Response from the LCO (Territory South) has been received. There is no record of chemical spillage and conviction in the study area in connection with land contamination.

Land Contamination Assessment

7.6.4 A Contamination Assessment Plan (CAP) has been prepared, as a separate document, for this Project. The CAP is contained in Appendix 7.1 of this report. This plan outlines the sampling locations, sampling and testing schedule for investigation works at A King Marine and the RHKYC. The approximate area of the subject shipyard and the yacht club are 2,504 m² and 19,068 m² respectively. According to EPD’s “Guidance Notes for Investigation and Remediation of Contamination Sites of: Petrol Filling Stations, Boatyards, and Car Repair / Dismantling Workshops”, eight and twenty eight sampling points would be sufficient for the A King Marine and the RHKYC, respectively. Sampling plans for the A King Marine and RHKYC sites are presented in Figures 7.1 and 7.2 respectively.

7.6.5 Since the study team could not gain access to the subject shipyard and the yacht club, the proposed sampling locations and number of sampling holes contained in the CAP are subject to review prior to site investigation works when access to the site becomes available.

7.6.6 A Contamination Assessment Report (CAR) shall be compiled after completing the site investigation works and obtaining results from laboratory. This report shall include comparison of findings with standards and interpretation. The laboratory testing results should be interpreted in accordance with the ProPECC Note No. 3/94. The contamination levels should be compared with Dutch guidelines or other international practices as appropriate.

7.6.7 Remediation Action Plan (RAP) should be prepared in accordance with EPD’s requirements if necessary and submitted to EPD for approval.

7.7 Identification of Potential Environmental Impacts

Potential Sources of Impact

A King Marine

7.7.1 As site inspection at A King Marine was not possible due to refusal from shipyard operators. Therefore, only a visual inspection was conducted outside the shipyard in May 2000.

7.7.2 Based on the preliminary site observations and our experience with shipyard operations, the following “hotspot” areas in light of land contamination were identified:

· Winch;

· Slipway;

· Storage Tank;

· Workshop;

· Chemical / Dangerous Goods Storage Area; and

· Waste Disposal Area.

7.7.3 Table 7.1 presents the potential contaminants that are likely to be found in the above-mentioned “hotspots”.

Table 7.1 Potential Contaminants Associated with Historical Shipyard Operations

Areas	Potential Contaminants
Winch	Lube oil
Slipway	Lube oil residue, anti-fouling agent, paint stripping
Storage tank	Petroleum product
Chemical storage area	Paint, chlorinated solvent, petroleum product
Waste disposal pit	Paint, chlorinated solvent, petroleum product, acid, Lube Oil, anti-fouling agent
Workshop	Paint, chlorinated solvent, lube oil, hydraulic oil

The Royal Hong Kong Yacht Club

7.7.4 Site inspection at the RHKYC was also not possible and only a visual inspection was conducted outside the club in May 2000.

7.7.5 Based on the preliminary site observations, the following “hotspot” areas in light of land contamination were identified:

· Workshop;

· Hoist;

· Boat Storage Area; and

· Car park.

7.7.6 Table 7.2 presents the potential contaminants that are likely to be found in the above-mentioned “hotspots”.

Table 7.2 Potential Contaminants to be found on The Royal Hong Kong Yacht Club

Areas	Potential Contaminants
Workshop	Lube oil, hydraulic oil
Hoist	Lube oil residue, anti-fouling agent, paint stripping
Boat Storage	Petroleum product
Car park	Petroleum product

Potential Impacts

7.7.7 The implications of potential land contamination for development at A King Marine and the RHKYC relate to the following:

· There may be potentially adverse effects on the health and safety of workers during site clearance / construction on site due to their potential exposure to hazardous or flammable materials in soil.

· Disposal of potentially contaminated spoil that will arise during site clearance / construction works.

· Based on the consultants’ experience in land contamination assessment for the same shipyard for Architectural Services Department (ASD) in 1994, contaminants were primarily due to the heavier fractions of petroleum hydrocarbons and heavy metals. These contaminants were relatively immobile and contamination was found to be localised and limited to the groundwater table. No off-site migration was detected.

7.7.8 It is currently proposed to reserve the site at A King Marine for an entertainment centre, with uses such as an indoor interactive theme park, game stalls, restaurants, shops and car parking. The estimated site area of the proposed complex is 7,736 m².

7.8 Prediction and Evaluation of Environmental Impacts

7.8.1 The study team could not gain access to A King Marine and the RHKYC to conduct any site investigation works. Therefore, we propose that the land contamination assessment or other relevant site investigation works should be conducted prior to the commencement of site clearance / construction works. A CAR should then be compiled to delineate the extent of land contamination and assess the associated environmental impacts. If land contamination is confirmed, a RAP should be devised and submitted to the EPD for approval. The CAR/CAP should be submitted to EPD for approval prior to the commencement of the site clearance / construction works.

7.8.2 Due to the above reasons, it is suggested that investigation works specified in the CAP or any subsequent additional investigation in relation to land contamination assessment should be conducted as part of the Implementation Schedule of the proposed mitigation measures in the decommissioning stage of the sites.

7.8.3 A land contamination survey was undertaken in 1994 at the area of A King Shipyard before that area was resumed for Causeway Bay Fire Station^([1]). The site investigation results (involved 6 trial pits) did not indicate any soil and groundwater contamination that warranted remediation. Based on the findings and recommendations of that Study, there is likely no insurmountable land contamination impact at the existing A King Shipyard.

7.8.4 According to the land use plan of the WDII Development, about half of the existing RHKYC area will be resumed for the development. However, most of the area to be resumed is carpark area and only a relatively small area, approximately 1,175 m², is used for the existing maintenance works area. As this area is protected by concrete paving and the scale of maintenance works at the RHKYC is smaller than that of the A King Shipyard, it is anticipated that potential land contamination at the maintenance area of the RHKYC will not be insurmountable.

7.9 Mitigation Measures for Land Contamination

7.9.1 Four possible options are proposed as follows depending on the extent of land contamination:

· if the contamination level is low, and risk assessment indicates that there are no significant risks, then leaving the contaminant in place in conjunction with capping / stabilisation may be appropriate;

· if the contamination level is high but the volume of contaminated soil is limited, the contaminated soil can be excavated and disposed of to landfill, subject to EPD’s agreement;

· if the contamination level is high and the volume of contaminated soil is significant, stabilisation may be necessary to treat the contaminated soil to levels suitable for leaving in-situ as far as possible;

· if floating oil exists on the water table, then free product recovery by pumps and bailing may be required.

7.9.2 Subject to sampling results, any contaminated land treatments are subjected to EPD’s requirements on handling, treatment and disposal. Where effluent stream is to be discharged from site, the discharge should comply with the WPCO and any EPD’s special requirements.

7.10 Mitigation Measures for Workers’ Health and Safety

7.10.1 The following precautionary measures should be implemented to minimise exposure hazards to workers during site clearance / construction works:

· site workers should wear appropriate personal protective equipment (that is, gloves, masks) when exposed to potential contaminated soil and groundwater;

· avoid stockpiling of spoils as far as possible;

· avoid using contaminated soil for landscaping;

· adequate washing facilities should be provided on site; and

· engage licensed collectors to collect any contaminated materials in accordance with the Waste Disposal Ordinance, Waste Disposal (Chemical Waste) (General) Regulation.

7.11 Environmental Monitoring and Audit Requirements

7.11.1 The requirements for environmental monitoring and audit (EM&A) with respect to land contamination, if necessary, should be determined upon completion of all relevant site investigation works.

7.12 Conclusion

7.12.1 This land contamination assessment includes a review of site history and environmental information, and a preliminary site inspection (outside the shipyard and the yacht club). Based on the available information, the potential for land contamination at the study area is considered not insurmountable. Potential contaminants arising from shipyard operations and the yacht club have been identified in Section 7.7.

7.12.2 The study team could not gain access to the subject shipyard and the yacht club for intrusive site investigation works at this stage. It is proposed that site investigation works should be conducted prior to the commencement of site clearance / construction works. Furthermore, the proposed sampling locations, sampling and testing schedule specified in the contamination assessment plan should be subject to review prior to the site investigation works. The CAP will be revised and submitted to EPD for approval prior to the commencement of the land contamination assessment work on site.

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([1]) CES (Asia) Ltd. (1994). Causeway Bay Divisional Fire Station Land Contamination Survey, Final Report.