Annex F Marine Archaeological Assessment Information

1 INTRODUCTION

1.1 THE PROJECT

The Hong Kong and China Gas Company Limited (Towngas) has proposed to develop a natural gas supply system from the Cheng Tou Jiao Liquefied Natural Gas Receiving Terminal (GRT), Shenzhen, People's Republic of China (PRC), to the Towngas Gas Production Plant (GPP) located in the Tai Po Industrial Estate, Hong Kong Special Administrative Region (HKSAR).

The system comprises two natural gas pipelines (approximately 18 inches in diameter) connecting the two sites and associated facilities consisting of a launching station at the GRT and receiving station at the GPP. The majority of pipelines will be installed through jetting techniques to enable the pipelines to be buried beneath the seabed in accordance with the requirements of the HKSAR Government Departments; the Marine Department (MD) and Civil Engineering Department (CED). A small portion of the pipelines route will require minor dredging activities to enable further protection for the security of the pipelines.

1.2 OBJECTIVES OF THE MARINE ARCHAEOLOGICAL INVESTIGATION

The following report presents the findings of the Marine Archaeological Investigation (MAI). The objectives of the MAI include the following:

* to identify and highlight the known and potential marine archaeological and historical resources within the Project area;

* to identify and map the potential archaeological and historical remains that may be impacted either directly or indirectly by the Project construction works; and

* to propose measures to mitigate impacts to any archaeological and historical remains identified.

The MAI has been prepared following the first three tasks of the Antiquities and Monuments Office (AMO) Guidelines for undertaking MAI (see Appendix A); Baseline Review, Review of Geophysical Survey and the Assessment of Archaeological Potential.

1.3 AREA OF REVIEW

The Project is proposed to be located in Tai Po Hoi (Tolo Harbour) in the south west, Chek Mun (Tolo Channel), and Tai Pang Wan (Mirs Bay) to the north east and extends to China. The investigation of the seabed for submerged archaeological and historical resources was limited to the marine area within the Hong Kong SAR border.

1.4 REPORT STRUCTURE

This report has been structured as follows:

Section 2: Legislative Framework - Provides the legislative framework for archaeological assessments in Hong Kong.

Section 3: Baseline Review - Provides the Baseline Review for the Project Area.

Section 4: Geophysical Survey - Provides the results of the geophysical survey review.

Section 5: Establishment of Describes the archaeological potential of

Archaeological the Project area based on the Baseline

Potential - Review and a review of the Geophysical

Survey and identification of potential impacts during the construction of the Project and recommendations, as applicable, for the protection of these features

2 LEGISLATIVE FRAMEWORK

The following legislation is applicable to the assessment of archaeological and historic resources in Hong Kong:

* Environmental Impact Assessment Ordinance (Cap. 499.S16). Technical Memorandum on the EIA Process (EIAO-TM);

* Antiquities and Monuments Ordinance (Cap. 53);

* Hong Kong Planning Standards and Guidelines (HKPSG); and

* Marine Archaeological Guidelines.

2.1 EIAO REQUIREMENTS

The submarine gas pipeline component of the project is considered to be a Designated Project under item H.2 of Part I of Schedule 2 of the Environmental Impact Assessment Ordinance (EIAO).

2.1.1 EIAO Study Brief

The Environmental Protection Department (EPD) has issued a Study Brief (ESB-087/2001), which outlines the requirements of the Environmental Impact Assessment (EIA) for the proposed Project, including the requirements for undertaking the Marine Archaeological Investigation (MAI).

The following Sections of the Study Brief are applicable:

Clause 3.4.9.1 "The Applicant shall follow the criteria and guidelines for evaluating and assessing the cultural heritage impacts as stated in Annexes 10 and 19 of the TM, respectively."

Clause 3.4.9.2 "The Applicant shall engage a qualified marine archaeologist to review available information to identify whether there is any possible existence of sites or objects of cultural heritage, for example shipwreck, within an area 10 metres on either side of the preferred alignment of the proposed gas pipelines and any seabed areas that would be affected by the marine works of the Project. If found, a Marine Archaeological Investigation (MAI) is required within the said area. The MAI shall be carried out by a qualified marine archaeologist who shall obtain a License from the Antiquities and Monuments Ordinance (Cap. 53). The requirements of the MAI are set out in Appendix E (of the EIA Study Brief)."

2.1.2 Technical Memorandum on the EIA Process

The EIAO-TM outlines the approaches required in investigating and assessing the impacts on cultural heritage sites. The following Sections are applicable:

Annex 19: "There is no quantitative standard in deciding the relative importance of these sites, but in general, sites of unique archaeological, historical or architectural value will be considered as highly significant. A baseline study shall be conducted: (a) to compile a comprehensive inventory of places, buildings, sites and structures of architectural, archaeological and historical value within the proposed project area; and (b) to identify possible threats of, and their physical extent, destruction in whole or in part of sites of cultural heritage arising from the proposed project."

The Memorandum also outlines the Criteria for Assessment of Impact on Sites of Cultural Heritage as follows:

Annex 10: "The criteria for evaluating impact on sites of cultural heritage includes: (a) The general presumption in favour of the protection and conservation of all sites of cultural heritage because they provide an essential, finite and irreplaceable link between the past and the future and are points of reference and identity for culture and tradition; (b) Adverse impacts on sites of cultural heritage shall be kept to the absolute minimum."

The Memorandum also outlines the approach in regard to the preservation in totality, in part, and not at all cultural resources:

Annex 19: "Preservation in totality will be a beneficial impact and will enhance the cultural and socio-economical environment if suitable measures to integrate the sites of cultural heritage into the proposed project are carried out. If, due to site constraints and other factors, only preservation in part is possible, this must be fully justified with alternative proposals or layout designs, which confirm the impracticability of total preservation."

2.2 ANTIQUITIES AND MONUMENTS ORDINANCE, CAP. 53

"This Ordinance provides for the preservation of objects of historical, archaeological and palaeontological interest..."

The Ordinance defines an antiquity as a relic (a movable object made before 1800) and a place, building, site or structure erected, formed or built by human agency before the year 1800. The Ordinance also states, amongst other things, that the discovery of an antiquity shall be reported to the Authority (Secretary for Home Affairs); that ownership of all relics discovered after 1976 shall be vested in the Government; that the Authority can declare a place, building, site or structure to be a monument, historical building or archaeological or palaeontological site or structure (and therefore introducing certain additional controls for these sites); and that licences and permits can be granted for excavation and for other work.

2.3 HONG KONG PLANNING STANDARDS AND GUIDELINES (HKPSG)

Chapter 10 of the HKPSG provides guidelines relating to the conservation of historic buildings, archaeological sites and other antiquities. The guidelines detail the methods for the conservation and preservation of protected monuments, the method of identifying and recording antiquities, particularly buildings that should be conserved and the recording and grading of such buildings and archaeological sites. The process of monuments and the development control through the planning process is also highlighted.

2.4 MARINE ARCHAEOLOGICAL INVESTIGATION (MAI) GUIDELINES

The AMO issue Guidelines for MAI which detail the standard practice, procedures and methodology which must be undertaken in determining the marine archaeological potential, presence of archaeological artefacts and defining suitable mitigation measures. The guidelines are provided in Appendix A for reference and includes a Baseline Review, Geophysical Survey and Establishing Archaeological Potential as the first stage of an MAI. Subject to the results of this, further investigation may or may not be required.

3 BASELINE REVIEW

3.1 INTRODUCTION

The objective of the Baseline Review is to establish a historical profile of the potential for submerged cultural heritage sites and to identify any details with regard to their presence. As part of the Baseline Review, research was undertaken at the British Library (BL) and the National Maritime Museum Library (NMML) in London, specific to the project, to identify any submerged cultural heritage features on charts. A literature review of historical information was also undertaken at the BL and NMML and a review of literature held by local tertiary institutions was also carried out. The information obtained during the Baseline Review is provided below in the following Sections.

3.2 DESCRIPTION OF THE PROJECT AREA

3.2.1 Historical Description

A Historical Description of the proposed Project area is provided below:

Horsburgh, 1855:420-42: "Mirs Bay, called Ty-Po-Hoy, is a deep inlet, 15 miles N.E. of Hong Kong, its eastern entrance-point, called Mirs Point, being in lat. 22(27'N., lon. 114(30'E. The bay at the entrance between Mirs Point and the opposite point, called Fung Head, is 5 miles wide; but a large black rock above water, named Gow-tow-pyah, and some other rocks under water to the S.W. of it, make the entrance for ships about 3 miles wide between the eastern shore and Gow-tow-pyah..

Gow-tow-pyah is a rock 90 feet above the sea, situated near the centre of the bay at the entrance; 5 1/4 cables from it S. 60( W., is a rocky ledge, part of which is always uncovered. The islet of South Gow lies 1 1/2 miles to the S.W. of this patch; it is 80 feet above the sea, and 5 cables from the point under Sharp Peak. Off this point are two islets, and the coast takes a sudden turn to the westward, forming a bay which will give good shelter from S.W. winds in 8 fathoms.

Grass Island lies 2 miles N.W. of South Gow, and is 1 1/4 from North to South, and half a mile from East to West. 3 1/2 cables from its eastern side is North Gow, a large black rock, with a reef awash at high water N. 40( W., 4 cables from it sunken rocks extend westerly from the reef.

To the northward of Grass Island is Port Island, the distance between the two being 7 cables. The reef just mentioned 5 1/2 cables' length from the S.E. point of the latter, which is 1 3/4 miles in circumference, and is 430 feet above the sea. Its eastern point is narrow, and projects 3 cables from the body of the island. On the North side of it is a good watering-place.

The western side of Mirs Bay, being much indented and also lined with islets affords many sheltered anchorages, the principal of which are Long Harbour and Tolo Harbour, with its entrance channel.

Long Harbour extends 3 miles South from the N.W. point of Grass Island which forms its eastern entrance. Both shores are steep until abreast of the South point of Grass Island, where the channel is somewhat contracted by shoal water near the shore of each side.

Having passed Grass Island, the harbour widens to 1 1/4 miles, and then gradually decreases towards its southern extremity, where it divides in two. The general depths in the harbour are from 7 to 9 fathoms.

Tolo Harbour, close to the westward of Long Harbour, has a channel five miles in length, leading to it in a S.W. direction from Port Island, which lies off its entrance. The entrance itself, however, is formed by Bluff Head (W.N.W. of Port Island) on the north and Flat Island (which lies 1 1/2 miles inside Grass Island) on the south. Gruff Head is a point about half a mile west of Flat Island, abreast of which the entrance channel is not more than half a mile wide. There are three reefs nearly mid-way in the Tolo channel; Knob Reef, 2 miles S.W. by W. of Gruff Head; Flat Reef two cables farther to the S.W., and Bush Reef 1 3/4 miles S.W. by W. 1/2 W. of the latter. Although there is a navigable passage on each side these reefs, the one to the northward of them is to be preferred, being the wider and having from 7 to 10 fathoms water.

The entrance to Tolo Harbour is half a mile beyond Bush Reef, and is formed by Harbour Island on the north and White Head on the south. It is not more than a mile wide, but immediately leads to an irregularly-shaped harbour of considerable extent. Its depths vary from 4 to 6 fathoms. Captain Collinson remarks that "Plover Cove the north-dash eastern cove of the harbour would probably be found the most eligible place in which to ride out a ty-foong".

The island of Peng-chow lies in the N.E. part of the bay, bearing North 4 1/2 miles from Gow-tow-pyah; it is 3 miles in circumference, and 148 feet above the sea. The distance between it and the nearest point on the mainland to the eastward is rather more than a mile, forming a convenient harbour, sheltered from all winds. The geological features are totally different from the adjacent land being alluvial, shale stones forming its beaches. E.N.E. from it is a remarkable conical peak, 753 feet above the sea.

The hills at Mirs Point rise to the height of 1200 feet and off its southern extreme is a small islet, which bears from Gow-tow-pyah S. 77( E. 4 1/4 miles. To the westward of it are some rocks, a cable's length from the shore, and the first point to the northward of it is perforated. The chart mentions numerous fishing stakes near the eastern shore in approaching Peng-chow, which, of course, must be guarded against. In passing along the eastern shore will be perceived a remarkable water course on the high land, where plenty of good fresh water will be found in the second small bay from the S.E. point. Between Peng-chow and the northern shore Captain Ross found 7 fathoms water on mud bottom, affording good anchorage when blowing hard from the southward. If you intend to anchor hereabout, keep from the N.E. point of Peng-chow, it being rocky to the distance of 1 1/2 cables' length. There are a few small villages in the bay, one of which is named Namo, and another Suilo-shaw, from whence numerous boats came off with people to look at the ships: all over the inner part of Mirs Bay there are many single fishing - stakes in 9 and 10 fathoms. High water at 9 hours on full and change of moon.

3.2.2 Contemporary Description

A Contemporary Description of Tolo Harbour and Mirs Bay is provided below:

Glibbery, 1995:34-40; Hownam-Meek, 1978:25-26: "Tolo Harbour is home to commercial shipping and has not much to offer a cruising yacht, except occasionally the chance to pick up diesel from a fuel barge in the middle of the harbour. The typhoon shelter to the north of Yim Tin Tsai, is too shallow for most yachts and fuel of fishing boats. With a fish farm outside its entrance, the chances of winning the race for space doesn't look good for yachts. Major reclamation is going on to the south east of the harbour, and it has been rumoured that building a rubbish dumping area is on the cards-yuk. If needing to drop off or collect crew, there are two government ferry piers on the western coast near the entrance to Sha Tin Hau (Tide Cove). This is where the ferry for all the other piers on the east coast of channel departs from, as it is situated near the KCR University Station."

The sailing directions and a description for Mirs Bay (including that around Grass Island, Long Island, Port Island, Jones Cove, Tolo Channel and Three Fathoms Cove) indicate that they are similar in regard to the noting of hazards, reefs and shallow water; the noting of numerous fish farms and abandoned pearl farms; the Police Barrier across the entrance to Tolo Harbour, and "... a drastic change in the colour of the water..." when entering Tolo Harbour.

The description of Mirs Bay is limited to those waters within Hong Kong jurisdiction. The opening to Mirs Bay is "...almost completely free of hazards..." and "...Tolo Channel presents no navigation snags at all..." It was also reported that "Except in typhoons the normal anchorage is NE of the Taipo Railway Pier. The water is shallow and the mud glutinous giving excellent holding. Inside Tolo Harbour (Tai Po Hoi) there is now a typhoon shelter in the bay between the unnamed island and Shun Wan Lei Uk promontory, the entrance, lit on both sides, being on the island side..."

3.3 REVIEW OF CHARTS

A review of the charts included Belcher's chart of 1841, which, although doesn't include Mirs Bay and Tolo Harbour, provides an indication of what may be located in the general marine region, including whether any shipwrecks were known to be located there. This chart is regarded as a valuable and accurate chart of the region, as Empson (1992:27) states, "Produced in meticulous style of the Royal Navy, this chart is remarkable for its accuracy and detail, containing a multitude of soundings which to this day form the basis of charts in unchanged areas."

There were no shipwrecks noted within the vicinity of the proposed pipeline routes on Belcher's chart. Given the amount of sea traffic in this area, and the apparent lack of any shipwrecks, is expected that Mirs Bay and Tolo Harbour may also be without shipwrecks. Other factors, such as navigation hazards, sailing knowledge and the suitability of ships used in the various areas would come into play, but Belcher's chart is a useful example of what could be expected around the New Territories. The charts of general Hong Kong, Southern China Sea area date back to the 15th century, but the most useful in terms of this investigation were those produced by the Royal Navy. During a review of the Royal Navy charts, the charts by Collinson in 1845 and Walker in 1847 were examined; both were located at the National Maritime Museum. No shipwrecks or other submerged features were shown on these charts for the subject area.

In addition, a chart of the South East Coast of China, which included a well defined and large scale (1:14,530) section of Tolo Harbour and Mirs Bay, published in 1903 from historical surveys was also examined and also yielded no shipwrecks or submerged man made features for the subject area. Other charts produced by the British War Office, of 1936 (BL 62855 [13]) and 1958 (BL 62855 [27]) were examined and they also failed to highlight any shipwrecks or other submerged cultural heritage features. The chart of 1936 does show a pier named "Tai Po Sta" which would indicate that ships loaded and unloaded in this region.

One of the most useful terrestrial maps of the area was produced in 1866 by an Italian missionary and titled "Map of Sun On District". Empson (1992:31) states that: "It remained the most useful map of the area until a survey of the New Territories was completed in 1901...Most copies surviving are reprints by the National Library of Australia from a copy held by them in the Braga Collection."

The map was inspected and although it provides some very useful information in regard to terrestrial sites, it does not highlight any sites of significance in the area of pipeline route. The Hong Kong Hydrographic Office was consulted with regard to any known shipwrecks in the project area and also reported no historic or recent shipwreck in the subject area.

3.4 LITERATURE REVIEW

It is reported that there is little known about the shipwrecks and other submerged cultural heritage sites located in Hong Kong waters. SDA Marine Ltd., (1999:2-4) has noted in previous reports that

"There are only 49-chartered shipwrecks in Hong Kong waters..."and that "From existing data available in the Hong Kong region, very little is known about the archaeological potential of seabed deposits. The only marine archaeological discovery was the remains (large planks and associated artefacts) of a late Sung/early Ming boat. No other shipwreck has since been found on the seabed. However, this is because there has been no systematic survey until the introduction of the EIA Ordinance in 1998." It is known that "An iron cannon cast in the Ming Dynasty (AD 1650) was found near Fut'ang Mên when dredging was vigorously pursued for the expansion of the Kai Tak Airfield..." (Lo, 1963).

Meacham (1975) notes a 'geometric' pottery site located north west of the Tai Po market, possibly dated to the 'soft geometric phase' of about 2200-1700 BC (Meacham, 1994:266). A similar period site has been located on the coastline of Lantau Island, being the Shek Pik site. It is indicative of the sites that could possibly have existed around the shores of Tolo Harbour, given the similar site near Tai Po. Other sites found at Shek Pik were prehistoric carvings and several hundred coins dated to "...the Sun period down to 1241-1253 AD..." (Meacham, 1975: viii). Other Neolithic, Bronze and Historical Period sites have been found in Tolo Harbour, Tolo Channel and Mirs Bay and it is possible that material could have been transported from these and other sites into the harbour and bay (see Figure 3.1a and 3.1b). However, it is often very difficult to locate this type of material (what could amount to isolated pottery shards for example) on, or below, the seabed.

Meacham (1975) also highlights the ferry/junk routes to Taipo from Hong Kong, and the Taipo and Sha Ue Chung (in China) routes, which are contemporary to Schofield of 1940 (cited in Meacham, 1975). They could possibly indicate an earlier regular trading network, which if it did, could possibly provide a source of shipwrecks from an earlier period. Endacott (1958:3) notes that the Puntis people settled this region of southern China during the 15th century:

"...followed by Hakka or 'guest people'. Before the close of the Ming Dynasty, a third group of Chinese settled in the area, the Hoklos. These people were less numerous than the other two, they came from the coastal district further north, and spoke a Fukien dialect. They were seafaring people, and, because of a greater leaning towards piracy than the other two groups, had a reputation for ferocity and daring which made them the terror of the coast."

Tai Po on the western shores of Tolo Harbour was also the location for the raising of the British flag in 1899 when claiming the New Territories, amongst civil unrest from local village militia (Morris, 1997:212-214). The District Office of the British Empire for the New Territories was based at Tai Po, the main building is known today as 'Island House'. "Here and there were the unmistakable white houses of district officials, with flagpoles in their gardens." (Morris, 1997:214). The headquarters and settlement would have brought an increase in the volume of transport to and from them, by road and sea. It is also reported that at the time of the annexing the New Territories, an American fleet was anchored in Mirs Bay (Cameron, 1991:193).

Another view of the region and the marine activities taking place around Tolo Harbour / Tai Po can be found in Lo (1963:163-164):

"Having inspected these sites in the urban area, we shall proceed to those scattered over the New Territories. Retracing Grampian Road, we turn into Tai Po Road which leads us over the range of hills to Sha Tin. The mount under which passes the railway tunnel was formerly known as Lion's Hill or Beacon Hill. The latter owes its origin to the fact that for a period towards the conclusion of the reign of K'ang-hsi (1661-1684 AD) an imperial decree requiring the coastal population to migrate inland was in force. Among the many centres where garrisons were stationed to give effect to this decree, one was established on this same mountain. Arriving as Sha-tin by Tai Po road, we turn east across the Li-yüan-yung Bridge to inspect the Big House of Tsêng Family. It is a huge castle-like walled structure, more splendid than fine, still possessing the characteristics of the architecture of the Hakka people. Returning to the market town of Sha-tin and the Tai Po Road, we pass the Chung Chi College at Ma Liu Shui, cross the rural district of Tai Po (Ta-pu) and arrive at the market town of Tai Po. It is the new town (Ta-pu Hsin-hsü) that is now prospering, the old town (Ta-pu Chiu-hsü) having declined in importance. Crossing the bridge and following the road that skirts Ta-pu Chiu-hsü we shall reach a place called Shun Wan (Ch'uan Wan). While on the road, we may occasionally glance at the much silted inlet of the sea. This was the western shore of what people of former times called the Ta-pu Sea. Arriving at Shun Wan, we may observe to the east the stretch of water designated in maps as Tolo Harbour. It was a plentiful pearl fishery, first systematically exploited under state control by the government on Nan Han, during the time of the Five Dynasties. Nowadays from the oysters (of the species that local fishermen called Ya Lo and Pearl Lo) landed here pearls can still be discovered from time to time, and these serve as evidence of the pearl-producing capacity of former times."

A further comment on the pearl farms located in Tolo Harbour can be found in Blackie (1957:237) in which it is stated that "A study has been made of the suitable locations in Tolo Harbour for the extension of the oyster culture...Following investigations it seems likely that Ostrea gigas Thunberg should do well and spats will be removed from Deep Bay for seeding..."

Blackie (1957:229) also provides information about the volume of local fishing vessels using Tai Po as a base for their fishing activities. The number of junks operating out of Tai Po was 523; the number of trawlers operating in the New Territories was 1094; the number of small, medium and big long-liners in the New Territories was 1469; and the total number of junks for Hong Kong and the New Territories was 6160. This volume of fishing junks working the Tolo Harbour and Mirs Bay regions, particularly the bottom scouring trawlers would undoubtedly have made a large impact on the existence and state of preservation of any submerged cultural heritage sites located there. In addition to the fishing activities in the area, Tolo Harbour has historically been the site of several land reclamations, which have disturbed the marine environment through dumping activities. Major reclamation works have occurred in Tai Po and Sha Tin. More recently, land reclamations have been undertaken at Pak Shek Kok and, previous to this, at Ma On Shan.

3.5 BASELINE REVIEW FINDINGS

Based on the baseline review of charts and literature, there are no specific marine sites that have been identified within the Project area that have been recorded to be of historical or archaeological significance. Due to the previous historical activity around the area of the proposed pipeline route, there is potential for the presence of submerged cultural heritage sites related to past human activities. However, the presence of such features would need to be considered in the context of the previous activities within the area, such as fishing activities, anchoring and land reclamation, which have resulted in significant disturbance to the seabed.

4 GEOPHYSICAL SURVEY

4.1 INTRODUCTION

The objective of the review of the geophysical survey is to define the areas of greatest archaeological potential, assess the depth and nature of the seabed sediments to define which areas consist of suitable material to bury and preserve archaeological material and to map anomalies on the seabed which may be archaeological material. The information obtained during the Baseline Review is provided below.

4.2 SURVEY METHODOLOGY

EGS (Asia) Limited undertook a geophysical survey for the project in June 2002, which covered a 700 m corridor (350 m either side of the proposed centreline) along the length of the proposed pipeline route (to the Hong Kong SAR boundary) (Figure 4.2a). The main traverses were set 70 m apart, with cross lines for interpretation at 300 m intervals. This survey allowed for a comprehensive investigation of the seabed, and below the seabed.

4.3 EQUIPMENT USED

The following equipment was used during the geophysical survey:

- EGS Seismic Profiler;

- Geoacoustics Pinger:

- Dual frequency echo sounder;

- Klein system 2000 dual channel side scan sonar;

- Sercel DGPS navigation system

In addition to the above, 19 vibrocores were sunk to a depth of 6 metres to sample the seabed sediments.

4.4 REVIEW OF GEOPHYSICAL SURVEY RESULTS

The geophysical survey data obtained by EGS were processed by in house geophysicists and included annotation of all anomalies recorded on the original records. A total of twelve alignment charts were produced by EGS comprising all the survey data: the seismic profile, high-resolution echo sounder, and side scan sonar for the 700 m corridor along the length of the pipeline, 350 m each side of the centreline, to the Hong Kong SAR boundary.

The entire side scan sonar raw data were reviewed by a qualified marine archaeologist to verify the anomalies and were then crosschecked with the alignment chart of the echo sounder and seismic data.

Table 4.4a lists 10 anomalies, which were identified in the Side Scan Sonar results and are possibly small boats or other submerged features (see Figure 4.4a for their location and Appendix B for raw data from the Side Scan Sonar survey).

Table 4.4a Side Scan Sonar Anomalies (Possibly Small Boats or Other Submerged Features)

Id.	Latitude	Longitude	Depth of water mPD	From Centre Line m	Dimensions	Comments
SC-01	22°33.5291’N	114°24.7183’E	16	1250 (n)	5.0x1.7x <0.5	Possible small boat, numerous trawler marks in vicinity
SC-02	22° 26.6717’N	114° 13.9017’E	10	172 (s)	16.7x3.0x1.4	Obvious vessel, possible barge, numerous trawler marks in vicinity
SC-03	22° 26.8266’N	114° 13.0462’E	9	316 (n)	6.2x2.0x<0.5	Possibly a medium sized boat broken into pieces, numerous trawler marks in vicinity
SC-04	22° 26.7701’N	114° 12.9292’E	9	244 (n)	3.2x1.3xnmh	Possible small boat
SC-05	22° 26.6077’N	114° 12.3209’E	8	51 (s)	6.3x2.9x<0.5	Most likely a small boat, anchor and trawler marks in vicinity
SC-06	22° 26.8876’N	114° 11.6545’E	5	60 (s)	6.5x2.6x1.0	Small boat near to SC-07
SC-07	22° 26.8906’N	114° 11.6667’E	5	38 (s)	21.2x6.7x1.3	Rectangular structure, possible barge or pontoon
SC-08	22° 27.0612’N	114° 11.6149’E	5	119 (n)	3.8x1.7xnmh	Small boat adjacent to seawall
SC-09	22° 26.8723’N	114° 14.4277’E	13.5	130 (n)	3.6x1.2x0.5	Possible boulder
SC-10	22° 27.2810’N	114° 15.4928E	c.12	285 (n)	4.2x1.5x0.7	Possible boat and ‘water tank’ near rocky point

nmh= no measurable height

Bearing = north (n), south (s), east (e), west (w)

Anomalies SC01-SC08, and SC10 are considered to be vessels. Anomaly SC-09, while initially interpreted as a boulder, could possibly be a cultural heritage feature or vessel. The majority of the anomalies are quite small, which would suggest that they are small fishing junks. As can be seen in the side scan sonar images provided in Appendix B, there are numerous scars from trawling and anchoring. Some of the vessels appear to be laying on-top of scars that are continuous either side of the vessel, suggesting that they have been deposited there since trawling began in the region (SC-01, SC-02, SC-06, SC-07). This is also possibly the case with SC-09, which would indicate that it was deposited after trawling and therefore possibly a cultural heritage feature rather than a natural feature. It is considered that anomaly SC-03 was at some stage a vessel of about 10-15 metres in length and has been hit by trawlers and pulled apart.

4.5 SUB-BOTTOM ANOMALIES

Some sub-bottom anomalies were identified within the 700m pipeline corridor using the seismic profiler, however no interpretation was made as to their nature and distance from the pipelines. These features are located in the Holocene layer, which comprises soft, silty marine sediments, which varies in depth up to 20 m. Given that major disturbances to the seabed have taken place, this Holocene layer could potentially provide a major source of undisturbed cultural heritage material.

A review of the seismic data for the centre-line was implemented in collaboration with EGS Geophysicists, who are best placed to provide this interpretation. The review of the seismic survey of the centre-line showed that there were no unidentified features along the route that were submerged below the seabed.

5 ESTABLISHMENT OF ARCHAEOLOGICAL POTENTIAL

5.1 INTRODUCTION

5.1.1 Baseline Review and Geophysical Survey

The review of the historical documents and literature indicated that Tolo Harbour and Mirs Bay were well used by fishers, traders and fish farmers for many years. It was also a place for the anchorage of larger vessels. The charts and literature reviewed provided no evidence of any submerged cultural heritage sites, including shipwrecks, in Tolo Harbour and Mirs Bay.

The geophysical survey carried out by EGS comprehensively surveyed a 700m pipeline corridor for all forms of submerged cultural heritage sites and objects. Of the 10 anomalies discovered on the seabed, each could be the remains of small vessels (in various states of preservation). None of the 10 anomalies are within 30 m of the current centre line. The geophysical survey also found that the pipeline corridor and surroundings have been greatly affected by fishing trawlers and anchors. This undoubtedly has had a great impact on the type and state of preservation of any submerged cultural heritage sites located on the seabed and below it, to an undetermined depth.

5.1.2 Preservation of Features

The side scan sonar 'images' provide a very effective picture of the recent history of the seabed. The seabed is a soft, silty mud/clay that shows a profusion of anchor and trawler scars. This would have had a great effect on the type, state of preservation and even existence of any cultural heritage sites located on the seabed and within a few metres below.

A 20 ton anchor will penetrate into the seabed by up to 8 metres in very soft mud, and trawler 'steel otter boards' will penetrate to 0.5m to 1m (Osorio in EGS, 2002). It is known that the fishing (by trawler) and anchoring in this region dates to at least the 1950s. From Blackie (1957:229) it is known that a large number of trawlers operated in this area. Ships and objects that were deposited on the seabed before bottom trawling, and that were quickly buried to a reasonable depth could still remain; those that were not buried could have been totally or partially destroyed.

If any interference with these sites has taken place, the remaining cultural material will lose much of its value as it is no longer in context with the other cultural material and its depositional environment. Interference can also cause acceleration in the breakdown of the fabric of the material due to a loss of surrounding concretion and an increase in biological and chemical attack.

Other activities such as the seawall around the gas production plant at Tai Po; the dredging and reclamation of the seabed in the Tolo Harbour region for the laying of the existing oil and water pipes; the disposal of unwanted debris and dumped material; the designated anchorages used by ships carrying dangerous goods in Mirs Bay and Tolo Harbour; and the possible deteriorating effects of water pollutants, has created a system where submerged cultural heritage sites would not fare well.

Other cultural heritage material transported into the harbour and bay would cause a mix of cultural material, also reducing the significance of this material. Yim and Jeung (1987:495) noted that " Because of the steep slope gradient of the stream courses [in the Tolo Harbour region] they are fast-flowing and possess high transportational capacities. The bulk of the effluents discharged into them are able to find their way into the harbour." They also highlight the eutrophication of the Tolo Harbour waters and the destruction of the mangroves from "...the discharging of large volumes of sewage and agricultural wastes into the harbour with the latter being derived from pig husbandry" and the "...input of heavy metals from industry..." and "...iron mine tailings..."

The chemistry involved within the sediments associated with this pipeline, particularly those in Tolo Harbour, could have a very detrimental affect on any biological and non-biological cultural heritage material.

5.1.3 Summary and Conclusions

A comprehensive baseline review of the literature and charts for this region; and a comprehensive and systematic collection and assessment of the seabed survey data concludes that:

* The pipeline route has the potential to include submerged archaeological deposits. However, due to the past human activities in the region, any surviving archaeological deposits are likely to have been disturbed.

* It is considered that the anomalies SC01-SC10 are likely to be small vessels (in various states of preservation) that have been relatively recently deposited (ie within the last fifty years) and are possibly associated with fishing in the area. Any cultural heritage sites/material situated on the seabed, and to an unspecified depth, before trawling began, would be in a very poor state of preservation or possibly totally destroyed.

REFERENCES

BL 62855 [13], 1936 and BL 62855 [27], 1958, Chart Call Nos. from the British Library, London.

Blackie, W.J., 1957, Hong Kong Fisheries. In Braga, J.M. 1957, Hong Kong Business Symposium. South China Morning Post. Hong Kong.

Cameron, N., 1991, A illustrated history of Hong Kong. Oxford University Press, Hong Kong

Empson, H., 1992, Mapping Hong Kong: A Historical Atlas. Government Information Services. Hong Kong

Endacott, G.B., 1958, A history of Hong Kong. Oxford University Press. London

Glibbery, J., 1994, Amongst the sampans : a guide for sailing boats and junks in Hong Kong's waters. Centurion Co., Hong Kong.

Lo, Hsiang-Lin, 1963, Hong Kong and its External Communications before 1842; the history of Hong Kong prior to British arrival.

Hong Kong Environmental Protection Department, 1997, Technical Memorandum on Environmental Impact Assessment Process. Hong Kong Environmental Protection Department.

Horsburgh, J., 1855, The India Directory or Directions for Sailing to and from the East Indies, China, Australia and the adjacent ports of Africa and South America. Vol. 1, 7th Ed. William Allen, Leadenhall Street, London.

Hownam-Meek, R.S.S., 1983, The local masters' seamanship manual and guide to Hong Kong waters. Lincoln Green, Hong Kong.

Meacham, W., (Ed.), 1975, An archaeological site at Shek Pik: Excavation Report and Related Papers by Walter Schofield (1888-1968). In Journal Monograph 1, Hong Kong Archaeological Society.

Meacham, W., (Ed.), 1994, Archaeological Investigations on Chek Lap Kok Island. In Journal Monograph IV, Hong Kong Archaeological Society.

Morris, J., 1997, Hong Kong: Epilogue to an Empire. Penguin. London.

Wallis, H., 1975, "Missionary Cartographers to China." In Geographical Magazine 47.

Wallis, H., 1988, "Chinese maps and Globes of the British Library and the Phillips Collection." British Library Occasional Paper, vol. 10

Lam, P.Y.K., 1986, Late 15th to 16th century blue and white porcelain from Penny's Bay, Hong Kong. Journal of the Hong Kong Archaeological Society 12: 146-162 (also in Vol 13: 79-80, Vol 12: 100-115)

SDA Marine Ltd., 1999, Study on Village Improvement and upgrading of Lei Yue Mun Area: Marine Archaeological Investigation. Hong Kong.

Osorio in EGS, 2002, A report by David Osorio on the penetration of anchors. EGS Desk Study Report, Job Number HK 172802.

Yim, W-S.W. and W.C. Leung, 1987, Sedimentology and geochemistry of sea-floor sediments in Tolo Harbour, Hong Kong : implications for urban development. In Society of Hong Kong Bulletin, Oct 1987, no. 3, p. 493-510.

Appendix A Guidelines for Marine Archaeological Investigation

Appendix B Side Scan Images