Appendix 8.2 - Contamination Assessment Plan for Government Sites

						Document Verification Page 1 of 1
Job title		Agreement No. CE61/2007(CE) North East New Territories New Development Areas Planning and Engineering Study - Investigation						Job number
								25278
Document title		Contamination Assessment Plan for Government Site						File reference
								8.34
Document ref		042-03
Revision	Date	Filename	G:\env\project\25278\reports\land contamination\Submission to CEDD (revised on 2009-09-02 Gov Site only)\037-00_Draft CAP fro Gov Site_Rev1.doc
Draft 1	03/09/09	Description	First draft
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Draft 2	28/02/13	Filename	G:\env\project\25278\reports\land contamination\Submission to CEDD (revised on 2009-09-24 Gov Site only)\042-00_Final CAP fro Gov Site_Rev1.doc
		Description	Update in accordance with EPD’s comment on 22 September 2009 and latest RODP
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		Description	Update in accordance with comments of various departments from 13 March to 10 April 2013 and revised RODP
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		Description	Update in accordance with comments of various departments from 10 May 2013 to 5 June 2013
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1 Introduction

1.1 Overview

The Planning and Development Study on North East New Territories (NENT Study, CE64/96) commenced in 1998 had identified areas in Kwu Tung North (KTN), Fanling North (FLN) and Ping Che/Ta Kwu Ling (PC/TKL) to be suitable for New Development Areas (NDAs). The NENT Study also confirmed the feasibility of NDAs based on the findings and recommendations from the technical assessments on various aspects including planning, environmental and engineering. In 2003, having regard to the housing demand at the time, the Government decided to shelve the NDAs proposal in the interim pending a comprehensive review of Hong Kong’s overall planning under the Study on Hong Kong 2030: Planning Vision and Strategy (HK2030 Study).

The HK2030 Study carried out by the Planning Department (PlanD) completed in 2007 was a comprehensive review of Hong Kong’s territorial development strategy for formulating a broad planning framework to guide the future development of Hong Kong up to 2030. It recommended proceeding with KTN, FLN and PC/TKL NDAs (i.e. NENT NDAs) as well as Hung Shui Kui NDA to address long-term housing demand and to provide job opportunities. NENT NDAs and Hung Shui Kui NDA were included as one of ten major infrastructure projects in the 2007-08 Policy Address. .

Further to the recommendations for NDAs in HK2030 Study, the Civil Engineering and Development Department (CEDD) and PlanD jointly commissioned the North East New Territories New Development Areas Planning and Engineering Study - Investigation (the Project) to formulate updated development proposals for NENT NDAs. The Project aims to review and update the findings and recommendations of the NENT Study, and to formulate revised proposals for NENT NDAs.

Section 3.4.9.4 of the EIA Study Brief No.: ESB-176/2008 for the NENT NDAs project dated January 2008 issued by the EPD specified that a land contamination assessment shall be undertaken and that a Contamination Assessment Plan (CAP) shall be submitted to the EPD for endorsement prior to conducting the assessment.

This CAP is prepared only for 4 identified government sites with potential land contamination issue where access for site investigation is available. A full CAP covering entire NENT NDAs project area will be prepared and submitted to EPD for approval separately.

1.2 Study Area

The NENT NDAs under this Study including Kwu Tung North (KTN) NDA, and Fanling North (FLN) NDA covering a total area of about 612ha as shown in Figure 1.1.

It should be noted that the development boundaries of the NDAs have been readjusted and fine-tuned during the planning stage. The Study Area outlined in Figure 1.1 is reference to the revised Recommended Outline Development Plan (RODP) of NENT NDAs study.

1.2.1 Kwu Tung North (KTN) NDA

The KTN NDA covers an area of about 450 ha. It is located to the west and northwest respectively of the proposed FLN NDA and the existing Fanling/Sheung Shui New Town. It is generally bounded by the Shek Sheung River in the east, Castle Peak Road and the Fanling Highway in the south, Tit Hang in the west and Tai Shek Mo (Crest Hill) in the north.

Long Valley is located at the south-eastern part of KTN NDA. The area comprises a mix of active and inactive wet and dry agricultural land, together with small areas of semi-natural freshwater marsh and areas formed as compensatory wetlands. River Beas (Sheung Yue River) runs in a southwest to northeast direction along the western side of the Long Valley. It joins Shek Sheung River at the northern tip of Long Valley. On both sides of River Beas are strips of low-lying land, and there are some ponds with flat lands used for agriculture.

The majority of KTN NDA lies on a relatively flat area within the central and southern parts where the main developed areas are located. They involve mixed land uses which comprise small residential developments, scattered villages, agricultural lands, rural areas and rural industries including vehicle repair, construction material storage, container storage etc. In particular, Yin Kong Tsuen and Ho Sheung Heung are the recognised villages within KTN NDA. They are located at the southern end of Long Valley and to the west of River Beas respectively. The reserved location for Kwu Tung Station of Lok Ma Chau Spur line of MTRC (formerly KCRC) is located to the south of Tung Fong and to the north of Dills Corner Garden.

Within the northern portion of KTN NDA, the elevation of the topography rises gradually as a series of east-west striking hills to Fung Kong Shan. A number of smaller valleys branch off through this high ground in a northeast to southwest orientation. The Lo Wu Classification Range is located near to the northern end of KTN NDA, and the Ma Tso Lung Restored Landfill is located at the north-western end of KTN NDA.

1.2.2 Fanling North (FLN) NDA

The FLN NDA covers an area of about 164 ha. It is located immediately to the north of the established Fanling/Sheung Shui New Town and to the southeast of the proposed KTN NDA. It is generally bounded by Wa Shan in the north, the Ma Wat River in the east, Ma Sik Road and Tin Ping Road in the south, Ng Tung River in the southwest and Sheung Yue River in the west.

The majority of FLN NDA lies on a relatively flat area with mixed land uses which comprise agricultural and rural areas with scattered villages, some small isolated buildings and residential developments. Rural industries including vehicle repair and material storage are concentrated on the two sides of Jockey Club Road with FLN NDA. There is no recognized village in FLN NDA.

Sheung Shui Slaughter House and Shek Wu Hui Sewage Treatment Works are located at the western end, and Sheung Shui Water Treatment Works is located immediately to the north of FLN NDA. San Wai Barracks and San Wai/Tai Ling Firing Range are located to the north-east of FLN NDA.

1.2.3 Ping Che / Ta Kwu Ling (PC/TKL) NDA

PC/TKL NDA, which is previously included as a part of the NDAs, would be subject to replanning and would be proceeded at a later stage. Thus, there will not be a revised RODP for PC/TKL NDA at this juncture and no EIA and contamination assessment would be required in this context.

1.3 Designated Project

The planning study for the NENT NDAs is a Designated Project (DP) under Item 1 of Schedule 3 of EIAO - Engineering feasibility study of urban development projects with a study area covering more than 20 ha or involving a total population of more than 100,000.

In addition, the following work components also fall under various Schedule 2 DP categories as summarized in Table 1.1a and Table 1.1b. The locations of the Schedule 2 Designated Projects are shown in Figures 1.2.1 – 1.2.3.

Table 1.1a - Schedule 2 Designated Projects in KTN NDA

Item	Work Component	Schedule 2 DP Category
1	San Tin Highway and Fanling Highway Kwu Tung Section Widening (between San Tin Interchange and Po Shek Wu Interchange) (Major Improvement)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road
2	Castle Peak Road Diversion (Major Improvement)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road.
3	KTN NDA Road P1 and P2 (New Road) and associated new Kwu Tung Interchange (New Road) and Pak Shek Au Interchange Improvement (Major Improvement)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road.
4	KTN NDA Road D1 to D5 (New Road)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road.
5	New Sewage Pumping Stations (SPS) in KTN NDA	F3	A sewage pumping station---(b) with an installed capacity of more than 2000 m3 per day and a boundary of which is less than 150 m from an existing or planned residential area or educational institution.
6	Proposed railway station and associated facilities in KTN NDA (To be conducted under other separated studies).	A2	A railway and its associated stations.
7	Utilization of Treated Sewage Effluent	F4	An activity for the reuse of treated sewage effluent from a treatment plant

Table 1.1b - Schedule 2 Designated Projects in FLN NDA

Item	Work Component	Schedule 2 DP Category
7	Utilization of Treated Sewage Effluent	F4	An activity for the reuse of treated sewage effluent from a treatment plant
8	Po Shek Wu Interchange Improvement (Major Improvement)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road
9	Fanling Bypass Western Section (New Road)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road
10	Fanling Bypass Eastern Section (New Road)	A1	A road which is an expressway, trunk road, primary distributor road or district distributor road including new roads, and major extensions or improvements to existing road.
11	Shek Wu Hui Sewage Treatment Works - Further Expansion at FLN NDA	F1	Sewage treatment works with an installed capacity of more than 15,000 m³per day.
12	Reprovision of temporary wholesale market in FLN NDA.	N3	A wholesale market.
13	New Sewage Pumping Stations (SPSs) in FLN NDA	F3	A sewage pumping station---(b) with an installed capacity of more than 2000 m³per day and a boundary of which is less than 150 m from an existing or planned residential area or educational institution.

1.4 Objectives

The purpose of this Contamination Assessment Plan (CAP) for Government Sites is to provide information, guidance and instruction to characterise land contamination and identify where any contamination is or may be present during the construction and operation of 4 identified government sites in NDAs. The objectives of this CAP are:

· To provide an account of the land use within project site boundary and relevant past land use history in relation to possible land contamination;

· To identify areas of potential contamination and the associated impacts, risks or hazards; and

· To identify the contaminant of concern and scoping of requirements for sampling and laboratory testing of soil and groundwater sampling.

1.5 Statutory Legislation and Evaluation Criteria

This CAP is prepared in accordance with the following Technical Memorandum and Guidance Notes:

· Annex 19 of the TM-EIAO, Guidelines for Assessment of Impact On Sites of Cultural Heritage and Other Impacts (Section 3 : Potential Contaminated Land Issues), EPD, 1997;

· Guidance Notes for Investigation Remediation of Contaminated Sites of Petrol Filling Stations, Boatyards, and Car Repairing/Dismantling Workshops, EPD, 1999 (i.e. superseded in August 2011);

· Guidance Manual for Use of Risk-Based Remediation Goals (RBRGs) for Contaminated Land Management, EPD, 2007; and

· Guidance Notes for Contaminated Land Assessment and Remediation EPD, 2007.

In accordance with EPD’s Guidance Note for Contamination Land Assessment and Remediation, a contamination assessment evaluation should:

· provide a clear and detailed account of the present use of the land and the relevant past land history, in relation to possible land contamination;

· identify areas of potential contamination and associated impacts, risks or hazards; and

· submit a plan to evaluate the actual contamination conditions for soil and/or groundwater, if required.

The EPD’s Guidance Notes include a summary of the general steps of a detail contamination assessment study.

Under the Annex 19 of the TM-EIAO, consideration shall be given to a number of potentially contaminating historical land uses, including oil installations, gas works, metal workshops, car repair and dismantling workshops, as having the potential to cause or have caused land contamination. All of these land uses have been identified either adjacent to, or within the NDAs area and work area boundary. This CAP has been prepared to set out the requirements for a baseline contamination evaluation of the NDAs area and work areas. A Contamination Assessment Report (CAR) will be prepared following site investigation activities. If significant contamination is identified in the CAR, a Remediation Action Plan (RAP) will be developed to deal with these areas during excavation works for the Project. The RAP should follow the contents requirements as specified in the EPD’s Guidance Notes for Investigation and Remediation of Contaminated Sites. A remediation Report (RR) will be prepared to demonstrate adequate clean-up and submitted to EPD for endorsement prior to the commencement of any construction/ development works within the NDAs.

2 Initial Site Appraisal

2.1 Desktop Review

A desktop study has been conducted to review past and present landuses and activities in the vicinity of these 4 government sites that may pose potential for land contamination. These 4 government sites include:

· KTN-23b,

· KTN-35a,

· KTN-77,78; and

· FLN-9a.

Locations of these 4 government sites are given in Figures 2.1.1 – 2.1.2.

Existing information from historical study report for areas located within the vicinity of these 4 government sites have been reviewed, including the following:

· Hong Kong Ordinance Survey Maps from various years;

· Relevant Outline Zoning Plans (OZPs) for Kwu Tung and Fanling;

· Hong Kong Geological Survey Maps (GSMs);

· Relevant aerial photos from 1963;

· Landuse information from the District Land Offices in Yuen Long (DLO Yuen Long) and Fanling (DLO North);

· “Mapping Hong Kong, A Historical Atlas”, Government Information Services, 1992; and

· “Environmental Impact Assessment Report for Planning and Development Study on North East New Territories”, CEDD and PlanD”, 2003.

The desktop review summary, including the historical aerial photos, has been provided in the full CAP to include desktop findings of all surveyed sites (i.e. approximately 300 sites have been surveyed). Nevertheless, the desktop review findings have no impact for deciding the detailed site investigation program of these 4 government sites.

The aerial photos of the 4 government sites were extracted and given in Appendix A.

2.2 Site Survey

Site surveys have been conducted in May and June 2009 to confirm findings of desktop study as well as to identify the hotspots for subsequent detail site investigation of these 4 government sites.

The existing land use and activities of these 4 government sites are summarized in Table 3.1.

2.3 Future Landuse and Activities

The RBRGs have developed four different post-restoration land uses, namely “Urban Residential”, “Rural Residential”, “Industrial” and “Public Parks”, to reflect the actual settings which people could be exposed to contaminted soil or groundwater. Definition of post-restoration land uses are given in EPD’s Guidance Note for Contaminated Land Assessment and Remediation and RBRGs Guidance Manual.

The revised RODP of NDAs is given in Figures 2.2.1 - 2.2.2, which consisted of different facilities, such as residential buildings, education institutions, outdoor sport facilities, commercial, mixed development, police facilities, primary and district distributors, sewage treatment works, sewage pumping stations, wholesale market, railway and monorail, pedestrian walkway, open space, car park and various of public utilities etc. The relevant RBRGs for the identified contaminated sites should be decided with reference to the revised RODP of NDAs. The most relevant RBRG corresponding to its future land use should be adopted in assessing its land contamination level.

Corresponding RBRGs landuse of the associated facilities are defined and given in Table 2.1.

Table 2.1 Post-restoration land use and RBRGs land use

Landuse	Corresponding RBRGs Landuse
Commercial / Residential · Urban High Rise · Low Rise in Rural Area	Urban Residential Rural Residential
Commercial / Business & Office	Urban Residential
School	Rural Residential
Public Park with Indoor Games Hall	Lower of Public Park or Urban Residential
Warehouse & Storage	Industrial
Government, Institution & Community Facilities	Urban Residential
Road including Pedestrian Walkway	Lower of Industrial or Public Park
Railway	Industrial
Open Space	Public Park
Public Utilities	Industrial

Nevertheless, if the future land uses is changed after the approval of this CAP or in doubt during the assessment (i.e. interpretation of the soil and groundwater testing results), the most stringent set of RBRGs should be adopted.

Site No.	Location	Current Land Use	Lot No.	Potentially Sources of Contamination	Approximate Area (m²)	Recommended No. of Boreholes⁽ⁱ⁾	Future Landuse (Corresponding RBRGs)
KTN-23b	Chung Hing Hong, petrol station (partially paved) Shell Gas (North of Castle Peak Road)	Fuelling Area/ Fuel Storage	DD95–T19636	Possible spillage/ leakage of fuel	203	2	Amenity (Public Park)
KTN-35a	Vehicle repair and maintenance (partially unpaved) (North of Ma Tso Lung Road)	Vehicle Repair	STT344	Potential spillage/ leakage of fuels and oils during maintenance activities	632	2	Public Rental Housing, Open Space (Urban Residential)
KTN-77	Container trailer park with vehicle repairing workshop (unpaved). Metal workshop (unpaved). (area behind saw mills) (Behind Saw Mills KTN-76)	Heavy Vehicle Parking and Repairing. Metal Painting on Unpaved Ground	No record	Possible spillage/ leakage of fuels, oils and other chemicals during previous storage and dumping activities (i.e. oil stain observed in some area)	5,421	8	Public Rental Housing, Open Space (Urban Residential)
KTN-78	Combine with 77	No record
FLN-9a	Luen Fat, vehicle repairing workshop (paved) (To the east of Woodland Crest)	Vehicle Repair	DD51–STT435	Possible spillage/ leakage of fuels and oils during maintenance activities	343	3	Road network (Lower of Industrial or Public Park)

Table 5.1 Sampling strategy

Locations			Coordinates		Sampling Strategy		Estimated No. of Samples ⁽¹⁾
NDA	Site ID	Borehole No.	Easting	Northing	Termination Level for Environmental Sampling (bgl) (mbgl) ⁽¹⁾	Frequency of Sampling Analysis ⁽²⁾	Estimated No. of Samples ⁽¹⁾
Kwu Tung North	KTN-23b (Figures 2.1.1, 5.1.1a & 5.1.1b)	KTN 23b-1	828497	840470	14.20 - (Drillhole Record at (E828509.67, N840339.42) in Jan 95 was referred. (i.e. ALLUVIUM ended at Saprolite layer of 14.10mbgl)	Drilling of a borehole and collection of soil samples at depths of 0.5, 1.5 & 3.0, and then at 3.0m intervals to the termination level for environmental sampling. One groundwater sample if encountered.	6 soil + 1 water samples
	KTN-23b (Figures 2.1.1, 5.1.1a & 5.1.1b)	KTN 23b-2	828504	840458			6 soil + 1 water samples
	KTN-35a (Figure 2.1.1, 5.1.2a & 5.1.2b)	KTN 35a-1	828455	841025	6.45 - (Drillhole Record at (E828480.29, N841189.88) in April 97 was referred. (i.e. COLLUVIUM ended at Saprolite layer of 6.45mbgl)		4 soil + 1 water samples
	KTN-35a (Figure 2.1.1, 5.1.2a & 5.1.2b)	KTN 35a-2	828468	841029			4 soil + 1 water samples
	KTN-77,78 (Figures 2.1.1. 5.1.3a & 5.1.3b)	KTN 77,78-1	827968	840911	1.50 + 4.50 = 6.00 (Drillhole Record at (E827999.14, N840957.17) in Nov/Dec 97 was referred. Owing to the relative thin COLLUVIUM layer ended at Saprolite layer of 1.5m, it is recommended to extend the Termination Level into the first layer of Saprolite (Grade V slightly gravelly sandy SILT/CLAY) from 1.5 to 6.0m		4 soil + 1 water samples
		KTN 77,78-2	827983	840935			4 soil + 1 water samples
		KTN 77,78-3	827989	840916			4 soil + 1 water samples
		KTN 77,78-4	828003	840921			4 soil + 1 water samples
		KTN 77,78-5	828021	840941			4 soil + 1 water samples
		KTN 77,78-6	828023	840925			4 soil + 1 water samples
		KTN 77,78-7	828014	840917			4 soil + 1 water samples
		KTN 77,78-8	828025	840907			4 soil + 1 water samples
Fanling North	FLN-9a (Figure 2.1.2, , 5.1.4a & 5.1.4b)	FLN 9a-1	832062	840917	10.3 - (Drillhole Record at (E832033, N840928) in Aug 88 was referred. (i.e. ALLUVIUM stopped at Saprolite layer of 10.3mbgl)		5 soil + 1 water samples
		FLN 9a-2	832073	840915			5 soil + 1 water samples
		FLN 9a-3	832075	840906			5 soil + 1 water samples

(1) The proposed Termination Levels for Environmental Sampling and Estimated No. of Samples are just for reference purpose. The exact termination levels and no. of soil/ groundwater samples of each borehole should be decided by the on-site Land Contamination Specialist.

(2) Historical drillhole records indicated that the water levels in the nearby areas of proposed boreholes are approximately ranged from 2 to 5 mbgl, hence, it is very likely to encounter the groundwater table of each proposed borehole.

5.3 Sampling Strategy

5.3.1 General

The sampling work will be undertaken following appropriate protocols, to minimise the potential for cross-contamination between samples and between different sampling locations. The soil sampling methods are based on techniques developed by USEPA. These methods include decontamination procedures, sample collection, preparation and preservation, and chain-of-custody documentation.

For general land contamination assessments, samples are collected by drillholes as the sampling depth will often exceed 3.0m. This will minimise the chance of cross-contamination between samples that are often observed when using the trial pit method. When conducting the intrusive investigations, care will be taken to avoid underground utilities.

Samples for laboratory testing will be taken with clean stainless steel hand tools and clean latex gloves and placed in rigid containers made of a material that is non-reactive with the likely contaminants.

In addition to the samples collected for laboratory analysis, a strata log will be kept for record of additional data to aid in the interpretation of results. Information on the general structure of the subsurface strata including grain size, colour, and wetness, and the depth and thickness of each soil/rock layer will be noted. The presence of any foreign material such as metals, wood, or plastics is also to be recorded.

All field personnel should wear adequate personal protective equipment when working in potential contaminated areas.

5.3.2 Decontamination Procedures

Equipment in contact with the ground shall be thoroughly decontaminated between each sampling event to minimize the potential for cross contamination. The equipment shall be decontaminated by steam cleaning, then washed with phosphate-free detergent and finally rinsed with water. Only clean water shall be used for drilling.

A clean area immediately adjacent to the sample location should be established, using a clean plastic sheet, on which all cleaned, and foil wrapped equipment may be placed.

During sampling and decontamination activities, disposable latex gloves shall be worn to prevent the transfer of contaminants from other sources. Disposable accessories, such as latex gloves, will be discarded after use.

5.3.3 Soil Sampling

Drillhole sampling

Drilling of borehole and collection of soil samples should be conducted at depths of 0.5m, 1.5m & 3.0m, and then at 3.0m intervals to the base. The on-site Land Contamination Specialist will decide the appropriate depths for sampling on a point by point basis.

Sufficient sample (see Table 5.2) should be placed in a pre-cleaned glass sample jar. The jar lid should be covered with laboratory solvent washed aluminium foil and lids. The jar must be filled with no void space (or otherwise if specified by the lab) for samples to be tested for VOCs. Each sample jar should be labelled. Records should be made of the details of the sampling location and other pertinent data. A chain-of-custody form should be completed for the samples. All samples should be stored on ice in portable ice chests between 2^oC – 4^oC whilst in the field or in transit.

Trial pit sampling

Trial pits should be constructed on site for soil and groundwater sampling if drilling sampling is not feasible. Trial pits can be constructed either manually or by an excavator, as judged as suitable by the site investigation contractor. Exact location of soil sampling should be determined on site by the on-site Land Contamination Specialist based on observation. The trial pits should be constructed to allow soil samples to be collected at:

· 0.5m below ground

· Level immediate above the groundwater level; and

· Level in between (i) and (ii) above for each sampling point.

Inspection of soil should be made at 0.5m intervals. The depth of the trial pit should be determined by the groundwater level and should be at least 0.5 m below ground level.

5.3.4 Groundwater Sampling

Groundwater samples shall be collected at each drillhole when groundwater is encountered. Historical drillhole records indicated that the water levels in the nearby areas of proposed boreholes are approximately ranged from 2 to 5 mbgl, hence, it is very likely to encounter the groundwater table of each proposed borehole. Anyhow, the on-site Land Contamination Specialist will decide whether the groundwater sample should be collected in accordance with the actual geological situation of the borehole.

Each sample shall be truly representative of the groundwater at the point from which it is taken, without dilution or contamination by water from other sources or by other material. A groundwater monitoring well shall be installed at each drillhole, and upon completion of installation of monitoring wells, approximately five times volumes of well shall be flushed to remove silt and drilling fluid residue from the wells. The wells shall then be allowed to stand for a day to permit groundwater conditions to equilibrate. Groundwater level and thickness of free product layer, if present, shall be measured by dip meter and interface probe respectively, before groundwater samples are taken. Moreover, prior to groundwater sampling, the sampling wells shall be purged (at least three times volumes of well) to remove fine-grained materials and to collect freshly refilled groundwater samples. After purging, one groundwater sample shall then be collected at each sampling well with a Teflon bailer. Field measurement of temperature and pH shall also be taken for each of the samples. The free products, if present, shall also be sampled to allow identification by the laboratory. Typical details of proposed groundwater monitoring well is shown in Appendix C.

If the permeability of the surrounding strata and storage is low, dewatering by pumping may dry up the hole, in which case the on-site Land Contamination Specialist will decide whether the requirement to pump out three times the liquid volume is to be waived.

After the dewatering process (and allowing groundwater to percolate back into the hole if it has been pumped dry), enough quantity of groundwater sample shall be collected from each drillhole, and then stored in different sample containers for analysis. Immediately after collection, samples shall be transferred to labelled sample containers containing the necessary preservatives (supplied by the laboratory). Samples shall be stored between 2^oC – 4^oC, and delivered to the laboratory within 24 hours. All samples shall be collected under chain-of-custody protocols.

5.3.5 Sample Size and Handling Criteria

Recommended sample size, sample containers and preservative procedures for each chemical analysis of the soil and groundwater have been summarized in Table 5.2. The containers shall be marked with sampling point codes and the depths at which the samples were taken. Samples shall be stored between 2^oC – 4^oC, and delivered to the laboratory within 24 hours.

Table 5.2 Summary of Sample Handling Criteria

Analytical Parameters	Sample Size	Sample Container	Preservation	Notes
Soil Sampling
All major analyses in soil sample	2 X 500g	Glass Jar with Teflon Lined Lid	Refrigeration at 2^oC – 4^oC	The soil jar must be filled to minimise headspace when volatiles are to be determined.
Groundwater Sample
Metals	250ml	Clear Plastic Bottle	Nitric Acid (HNO₃) Refrigeration at 2^oC – 4^oC	For Dissolved Metals the sample must be filtered prior to acidification.
TPH (C₆ – C₈) & VOCs	2 X 40ml	Glass Vial with Teflon Lined Lid	Hydrochloric Acid (HCl) Refrigeration at 2^oC – 4^oC	The vials must be filled for zero headspace.
	2 X 40ml	Glass Vial with Teflon Lined Lid	Hydrochloric Acid (HCl) Refrigeration at 2^oC – 4^oC	The vials must be filled for zero headspace.
TPH (C₉ – C₁₆)	1L	Amber Glass Bottle with Teflon Lined Cap	Refrigeration at 2^oC – 4^oC	-
TPH (C₁₇ – C₃₅)
SVOCs
PCBs

5.3.6 Analytical Programme and Parameters

Soil and groundwater samples collected at each sampling point should be analyzed for parameters in accordance with sampling and testing schedule shown in Table 5.3 and analysed by a HOKLAS accredited laboratory accordance with analytical method given in Table 5.4.

Table 5.3 Sampling and Testing Schedule

Locations		Existing Landuse	Testing Parameters
Locations		Existing Landuse	VOCs	SVOCs	Metals	TPH	Cyanide	PCBs
Kwu Tung North	KTN-23b	Chung Hing Hong, petrol station	√	√	√	√
	KTN-35a	Vehicle repairing workshops	√	√	√	√
	KTN-77,78	Container trailer park	√	√	√	√	√	√
Fanling North	FLN-9a	Luen Fat, vehicle repairing workshop	√	√	√	√

· Volatile Organic Compounds (VOCs): acetone, benzene, bromodichloromethane, 2-butanoe, chloroform, ethylbenzene, methyl tert-butyl ether, methylene chloride, styrene, tetrachloroethene, toluene, trichloroethene, xylenes (total)

· Semi Volatile Organic Compounds (SVOCs): acenaphthene, acenaphthylene, anthracene, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(g.h.i)perylene, benzo(k)fluoranthene, bis-(2-ethylhexyl)phthalate, chrysene, dibenzo(a,h)anthracene, fluoranthene, fluorene, hexachlorobenzene, indeno(1,2,3-cd)pyrene, naphthalene, phenanthrene, phenol, pyrene

· Metals: antimony, arsenic, barium, cadmium, chromium III, chromium VI, cobalt, copper, lead, manganese, mercury, molybdenum, nickel, tin, zinc

· Total Petroleum Hydrocarbon (TPH): Carbon Ranges C6-C8, C9-C16 and C17-C35

· Polychlorinated Biphenyls (PCBs)

· Cyanide: Cyanide, free (i.e. only for soil samples)

Table 5.4 Method of Analysis for Soil and Groundwater Samples

Parameter	Referenced Analytical Method	Reporting Limit for Soil (mg/kg)	Reporting Limit for Groundwater (mg/L)
VOCs
Acetone	USEPA Method 8260	5	0.05
Benzene		0.2	0.005
Bromodichloromethane		0.1	0.005
2-Butanone		5	0.05
Chloroform		0.05	0.005
Ethylbenzene		0.5	0.005
Methyl tert-Butyl Ether		0.5	0.005
Methylene Chloride		0.5	0.05
Styrene		0.5	0.005
Tetrachloroethene		0.04	0.005
Toluene		0.5	0.005
Trichloroethene		0.1	0.005
Xylenes (Total)		1.5	0.015
SVOCs
Acenaphthlene	USEPA Method 8270	0.5	0.002
Acenaphthene		0.5	0.002
Anthracene		0.5	0.002
Benzo(a)anthracene		0.5	-
Benzo(a)pyrene		0.5	-
Benze(b)floranthene		1.0	0.004
Benzo(g,h,i)perylene		0.5	-
Benzo(k)fluoranthene		1.0	0.004
Bis-(2-Ethylhexyl)phthalate		5.0	-
Chrysene		0.5	0.002
Dibenzo(a,h)anthracene		0.5	-
Fluoranthene		0.5	0.002
Fluorene		0.5	0.002
Hexachlorobenzene		0.2	0.004
Indeno(1,2,3-cd)pyrene		0.5	-
Naphthalene		0.5	0.002
Phenanthrene		0.5	0.002
Phenol		0.5	-
Pyrene		0.5	0.002
Metals
Antimony	USEPA Method 6020A	1	-
Arsenic		1	-
Barium		0.5	-
Cadmium		0.2	-
Chromium III		0.5	-
Chromium VI		0.5	-
Cobalt		0.5	-
Copper		1	-
Lead		1	-
Manganese		0.5	-
Mercury		0.05	0.0001
Molybdenum		1	-
Nickel		1	-
Tin		0.5	-
Zinc		1	-
TPH
C6-C8	USEPA Method 8015	5	0.02
C9-C16		200	0.5
C17-C35		500	0.5
PCBs	USEPA Method 8080	0.1	0.0001
Cyanide, free	USEPA Method 9010A	1	-

A HOKLAS accredited (or equivalent) testing laboratory shall be appointed to conduct chemical analysis for the soil and groundwater samples. All laboratory tests shall be made in accordance with Guidance Manual for Use of Risk-Based Remediation Goals for Contaminated Land Management. The RBRGs for soil and soil saturation limits, and RBRGs for groundwater and groundwater solubility limits are given in Appendix D.

5.3.7 Storage of Surplus Soil Samples

It is envisaged that the likely scale of contamination should be very much localized, if found. The volume of soil expected to require cleanup should be of small quantities. Landfill disposal may be a practical option and should be considered as the last resort. Additional tests in terms of Toxicity Characteristic Leaching Procedure (TCLP) would be required to meet the criteria for disposal to landfills. Hence, surplus soil samples obtained during the site investigation would be stored for subsequent TCLP tests if identified necessary.

Landfill disposal Criteria for Contaminated Soil is show in Table 5.5.

Table 5.5 Landfill Disposal Criteria for Contaminated Soil

Parameter	TCLP Limit (ppm)	Referenced Analytical Method	Detection Limit (mg/L)
Cadmium	10	USEPA Method 1311 and 6020A	0.2
Chromium	50		1
Copper	250		1
Nickel	250		1
Lead	50		1
Zinc	250		1
Mercury	1		0.2
Tin	250		1
Silver	50		1
Antimony	150		1
Arsenic	50		1
Beryllium	10		1
Thallium	50		1
Vanadium	250		1
Selenium	1		0.2
Barium	1000		1

Ref: EPD’s Guidance notes for investigation and remediation of contaminated sites of: petrol filling stations, boatyards, car repair/ dismantling workshops

5.3.8 Quality Control and Quality Assurance (QA/QC)

A proper QA/QC program shall be established to ensure that the data collected are accurate and representative of actual soil and groundwater conditions. The QA/QC programme shall include the following:

· 1 duplicate per 20 samples;

· 1 equipment blank per 20 samples;

· 1 field blank per 20 samples; and

· 1 trip blank per trip for the analysis of volatile parameters.

5.3.9 Sample Handling, Packaging and Transport

The soil and groundwater sampling shall be conducted by an experienced sampling technician (provided by the G.I. Contractor), and the appropriate procedures shall be adhered to. Sampling methodologies are based on the techniques developed by the USEPA. Collection tools shall be cleaned thoroughly before, in-between and after sampling. Special care shall be taken to prevent any cross contamination of the samples during collection, handling, and storage.

Sample containers shall be laboratory cleansed, airtight, and made of glass or other suitable materials with Teflon-lined lids to ensure that the container does not react with the sample or absorb contaminants. Care shall be taken when recording and labeling the sample information on the containers. Information such as the date/time, sample point codes, depths, and any other relevant data shall be included. Samples shall be stored in an icebox (at about 2^oC – 4^oC) immediately after collection and labeled, until they can be transported to the laboratory for analysis.