ISLAND WIDE CONSTRUCTION RAW MATERIAL SURVEY

REPORT ON DISTRICT

by

Mahesh Wickramasinghe

Geologist

Report No: MR/CRM/13/2018

GEOLOGICAL SURVEY & MINES BUREAU

No. 569, Epitamulla Road

Pitakotte

July, 2018

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CONTENTS

Page

1. Introduction 04

2. Objectives 05

3. Methodology 05

4. Area and Boundary 05

5. Location and Accessibility 07

6. Climate 07

7. Physiography and Drainage 08

8. Outline of Geology 08

9. Construction Raw Materials 10 9.1 Rock 12 9.2 Gravel/Soil 15 9.3 Sand 17

10. Conclusions 18 11. Recommendations 19

Acknowledgements 20

References 21

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List of Annexures

01 – Details of newly identified Rock occurrences in

02 - Details of newly identified Gravel/Soil occurrences in Vavuniya District

03 – Working Rock quarries, Gravel/Soil pits and River sand deposits in Vavuniya District

04 – Construction Raw Material Resources Map of Vavuniya District

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ISLAND WIDE CONSTRUCTION RAW MATERIAL SURVEY REPORT ON VAVUNIYA DISTRICT

12. Introduction

Over the past two decades, state as well as private sector organizations initiated rapid development work throughout the country in a large scale.

Of these projects, Port City development project, construction of expressways (i.e. Northern and Central expressways, extension of Southern expressway to and Mattala), extension of Southern Railway line from Matara to Kataragama and construction of a massive building complex for the Ministry of Defense and Three Forces Head Quarters in Pelawatta and other government office complexes in Battaramulla, construction of irrigation and hydro power projects in many parts of the country, construction of multi storied apartment complexes in urban and suburban areas, are the most significant. For these projects, huge quantities of building raw materials (sand, rock and soil / gravel) are required.

Being the regulatory authority on Mines and Minerals Act No. 33 of 1992 and amended Act No. 66 of 2009, it is the responsibility of the GSMB to identify mineral resources in the country, including building raw materials, required for various industries and development projects, initiated by the state as well as the private sector.

In the recent past, the contractors of various development projects have complained about the difficulties faced by them when identifying suitable localities for extracting and supplying building raw materials needed for the major development projects, currently initiated in many parts of the country. This has resulted in delaying construction work of some of the government high priority development projects.

This matter was reported to Mr. R. Paskaralingam, Senior Advisor to the Ministry of National Policies and Economic Affairs by the relevant parties at the progress review meetings of the government development projects, held at the Ministry. Subsequently a request was made to the Director General, GSMB by Mr. R. Paskaralingam, to immediately initiate an island wide survey to identify minable locations of building raw materials (sand, rock and soil / gravel) and to estimate their resources in order to use them as per the requirements of the projects.

Accordingly, GSMB has commenced an island wide construction raw materials survey in early 2017. This report including maps, tables and annexes is the output of the survey conducted in Vavuniya district.

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13. Objectives

The objectives of this survey are as follows.

 Conducting field surveys to identify suitable sites for mining construction raw material (sand, gravel and rocks) resources.  Identification of mining related issues and environmental concerns.  Preparation of construction raw material resources map.  Assessment of mineable quantities of construction raw materials in identified locations and optimum extraction limits.

14. Methodology

Initially, all the available data on construction raw material occurrences within the district were collected and a base map of construction raw materials for the district was prepared (both soft and hard copies). All topographic maps (1: 50,000) which cover entire district was also collected.

After preparing all the documents, the assigned field crew left for Vavuniya to commence field investigations in mid-December 2017. The field camp was established in Thekkawaththa, which is situated near Vavuniya town.

Field work in entire district was conducted in two and a half month period and during this period all the accessible areas in the district were investigated. After completing the field investigations, field crew returned to head office in late-February 2018 and commenced final map and report preparation work.

15. Area and Boundary

Total land area of Vavuniya district is approximately 1,980 square kilometers. The district is bounded on the East by part of district and part of Mullaithivu District, on the West by Mannar district on the North by Mullaithivu district and South by Anuradhapura district. The district comprises of four divisional secretarial divisions, namely, Nedunkerni (Vavuniya North), Vavuniya South Tamil, Vavuniya South Sinhala and Cheddikulam (Fig. 1). Number of Gramaniladhari divisions in Vavuniya district is 102 and there are 505 villages.

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Figure – 1: Divisional Secretariat Divisions of Vavuniya District

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16. Location and Accessibility

The area covered by Vavuniya district lies within 1:50,000 sheets of Mankulam, Padawiya, Palampiddi, Madhu Road, Tanthrimale and Vavuniya. The main township in the district is Vavuniya while Cheddikulam, , Kanakarayankulam, Omantei Irattaperiyakulam, Mamaduwa, Poowarasankulam, Parayanalankulam and Nedunkerni are the medium scale townships located within the district.

Access to the Vavuniya district is manily through the – (A 09) main road. The eastern part of the district can be accessed through the Vavuniya – Kebitigollewa (A 29) road while western part of the district could be reached by Vavuniya – Mannar (A 30) and Medawachchiya – Mannar (A 14) roads. Puliyankulam – Mullativu road lies within the NE part of the district. These main roads are connected by a fair network of provincial roads (C and D grade) and Pradesiya sabha roads (E and F grade).

Colombo – Kankasanthurei and – Talaimannar railway lines are the two railway lines run across the district. Colombo – Kankasanthurei railway line extends from south of Irattaperiyakulam to Puliyankulam in N/NE direction and from Puliyankulam to South of Mankulam in N/NW direction. The Colombo – Talaimannar railway line extend from Neriyakulam to south of Madhu road in NW direction within the district.

17. Climate

The area covered by Vavuniya district falls within the Dry Zone of , where tropical dry climate is prevalent.

Rainfall The area covered by the district receives somewhat low rainfall within a year. Annual rainfall figures in the district vary from 1000 – 1500mm. The area experiences heavy rain from October to December, during NE monsoonal season. In comparison, amount of rainfall receives during the rest of the year is considerably low.

Monthly Average Temperatures The highest average monthly temperature is recorded in the months of June, July & August (360C) while the lowest average monthly temperature is encountered in the months of January and December (250C). The mean annual temperature is about 34Co.

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18. Physiography and Drainage

Physiographically the area covered by Vavuniya district belongs to lowest peneplain of Sri Lanka. The relief of the district varies from 100 – 200m above MSL. Generally, the area comprises flat terrain with small scattered hillocks present as inselbergs. The topography becomes more pronounced in SE sector while a flat terrain is identified in rest of the areas within the district. Madukanda, Thammannakanda and Welikanda are prominent strike ridge structures identified within the district. They are located in SE sector, representing higher elevations in the district. Within these ridge structures number of metal quarries are being operated.

Major river systems are absent within Vavuniya district. However, number of small to medium scale streams are drained through the district and all of them are seasonal streams which are active only during NE monsoon period. Kanakarayan Aru, Chamali Aru, Kiul Aru, Chamalankulam Aru, Per Aru, Kal Aru and parts of Malwathu Oya are the main stream system draining within the district. These river systems show a remarkable variability in discharge during dry and wet seasons.

One of the specialties of Vanni region is that the villages are named with the tanks. According to ancient chronicles, many tanks had been constructed during the period of Nagas by obstructing the rivers. The tanks had been constructed in the plains to store the water flowing in rainy seasons from the Central Highlands. As at present there are 719 medium and minor tanks available in Vavuniya district. The largest irrigation scheme of the district is Pavatkulam. This tank was constructed by obstructing the Kallaru River which flows through the Iratperiyakulam. There are several minor tanks in the areas to where the water flows from this tank.

19. Outline of Geology

Ninety percent of the island of Sri Lanka is underlain by Proterozoic high grade metamorphic rocks with Quaternary sediments being restricted to the NW, N and NE coastal region as a narrow strip (Fig. 2). The Precambrian basement is divided into three major lithotectonic units, namely, Highland Complex (HC), Wanni Complex (WC) and Vijayan Complex (VC) (Fig. 2).

Geologically, the entire Vavuniya district lies within the Wanni Complex (WC) of Sri Lanka (Fig. 2).

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Figure – 2: Simplified Geological Map of Sri Lanka showing Boundary of Vavuniya District

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The Wanni Complex is characterized by thick sequences of ortho-gneisses which is comprised of amphibolite grade, migmatitic, granitic and granodioritic gneisses in northwest and western sections of the country. Towards the northeast, granulite grade variants such as charnockitic rocks and minor granulite grade meta-sediments are common.

A part of the Wanni Complex is made up of amphibolite facies rocks but areas ad jacent to the Highland Complex comprises of granulite facies rocks which include both charnockites and met pelites.

Wanni Complex rocks in the western and NW parts of the district falls into the Vavuniya Charnockite Province (VCP), characterized by relatively young ages in comparison with much older ages in the adjacent Highland Complex.

Exposures of Proterozoic metamorphic rocks are somewhat prominent within the southern part of the Vavuniya district. Of these rocks, granulitic gneiss, biotite gneiss, biotite hornblende gneiss, charnockite and charnockitic gneiss are the most commonly occurred rock types.

In western and northern sections of the district, exposures of hard rocks are rare due to the presence of thick sequence of ferruginized gravel formations as top formation above the hard rocks. ferruginized gravel formations are residual formations and they represent the alteration products of subjacent Precambrian hard rocks. The genetic connection between the two formations is clearly visible in some well sections.

Minor occurrences of Miocene limestone is identified in the Periyakaddu area in the western part of the district, surrounded by Wanni Complex rocks. This is the only location of Miocene limestone rocks identified within the district.

20. Construction Raw Materials

The occurrences of following construction raw material were investigated and their resources were estimated.

 Rock  Gravel/Soil  Sand

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During the field investigations special attention was given to locate rock and gravel/soil occurrences within Vavuniya district. Since no major river flows through the district, it lacks prominent river sand deposits. A few small scale sand deposits can be encountered associated with the medium scale stream system.

20.1 Rock

Rock outcrops are much prominent in the southern part of the Vavuniya district and they are comparatively rare in the northern part. Most of the large rock outcrops found in Vavuniya district are either being mined or abandoned quarries. Several untouched rock outcrops are also encountered.

Major rock types in the study area are charnockitic gneiss, charnockites, hornblende biotite gneisses and granitic gneisses. Rocks which can be used as construction materials are classified as follows, based on the type of the outcrop and the extent of the outcrop.

Outcrops with mineable quantity less than 50,000 cubic meters are categorized as small, outcrops with mineable quantity between 50,000 and 100,000 cubic meters are categorized as medium and outcrops with mineable quantity more than 100,000 cubic meters are categorized as large.

Outcrops located near archeological sites, in highly populated areas, near lakes or inside the thick forest were not investigated and not included in this report. All other rock outcrops found to be suitable for mining are described below and details of them are given in annexures 01, 02 and 03.

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Small Scale Outcrops

Both above and below surface small scale outcrops are encountered within all four DS divisions of the district. Some of them can be economically mined. In some locations currently operating small scale mines are present (Plate 1 and 2).

Plate 1: Below Surface Small Scale Outcrops

Plate 2: Above Surface Small Scale Outcrops

Small Scale Outcrops Number of Total Mined Out Available Remarks Outcrops Volume (m3) Volume (m3) Volume (m3)

Outcrop wise details are given 65 735,850 59,550 676,300 in the annexures

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Medium Scale Outcrops

Both above and below surface medium scale outcrops are mainly found in southern part of the district. In other parts of the district medium scale outcrops are not very common. Most of these outcrops are being mined at present, but several untouched outcrops are also present within the district (Plate 3 and 4).

Plate 3: Below Surface Medium Scale Outcrops

Plate 4: Above Surface Medium Scale Outcrops

Medium Scale Outcrops Number of Total Mined Out Available Remarks Outcrops Volume (m3) Volume (m3) Volume (m3)

Outcrop wise details are given 6 478,000 45,700 432,300 in the annexures

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Large Scale Outcrops

Both above and below surface large scale outcrops are mainly found in southwestern part of the district. All operating large quarries and the outcrops which can be developed into large quarries are associated with the isolated hillocks of Madukanda, Thammanakanda and Welikanda (Plate 5 and 6). Almost all the large outcrops within the district, can be economically mined, but proper mining procedures should be followed to minimize any environmental damage.

Plate 5: Below Surface Large Scale Outcrops

Plate 6: Above Surface Large Scale Outcrops

Large Scale Outcrops Number of Total Mined Out Available Remarks Outcrops Volume (m3) Volume (m3) Volume (m3)

Outcrop wise details are given 12 15,995,000 1,941,500 14,053,500 in the annexures

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20.2 Gravel/Soil

Gravel occurrences can be observed in many parts of the Vavuniya district as small deposits in some areas and large deposits that spreads over few kilometers at some places. Three main types of gravel formations have been identified, namely, weathered rock gravel beds (ferruginized gravel formations), quartzitic gravel formations and pegmatitic gravel formations. These three types of gravel beds have been formed as a result of weathering of gneissic, quartzitic and pematitic rocks respectively.

To describe the minable quantities of gravel deposits, they are further divided into 3 groups as small, medium and large. Gravel occurrences with mineable quantities less than 50,000 cubic meters are categorized as small occurrences, gravel occurrences with mineable quantities between 50,000 and 100,000 cubic meters are categorized as medium occurrences and gravel occurrences with mineable quantities more than 100,000 cubic meters are categorized as large occurrences.

Small Scale Gravel Occurrences

There are a number of operating and abandoned gravel quarries in many parts of the district. Several locations with untouched gravel occurrences are also observed (Plate 7). Most of these small scale gravel occurrences are of ferruginized or pegmatitic type.

Plate 7: Small Scale Gravel Occurrences

Small Scale Gravel Occurrences Number of Total Volume Mined Out Available Remarks Occurrences (m3) Volume (m3) Volume (m3)

Occurrence wise details are 44 530,200 153,325 376,875 given in the annexures

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Medium Scale Gravel Occurrences

Medium scale gravel occurrences are identified only in the Nedunkerni DS division, and they are ferruginized gravel beds (Plate 8).

Plate 8: Medium Scale Gravel Occurrences

Medium Scale Gravel Occurrences Number of Total Volume Mined Out Available Remarks Occurrences (m3) Volume (m3) Volume (m3)

Occurrence wise details are 2 120,000 44,000 76,000 given in the annexures

Large Scale Gravel Occurrences

Large scale gravel occurrences are observed mainly in the middle and southern part of the district and most of them are quartzitic formations. Some of them are mined in large scale, but several untouched locations are also present (Plate 9).

Large Scale Gravel Occurrences Number of Total Volume Mined Out Available Remarks Occurrences (m3) Volume (m3) Volume (m3)

Occurrence wise details are 11 9,852,500 3,120,000 6,732,500 given in the annexures

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Plate 9: Large Scale Gravel Occurrences

20.3 Sand

Since no major river flows through the district, special attention was not given during field investigations for river sand occurrences. Only a few small scale river sand deposits associated with seasonal stream system could be observed. They bear a very little quantity of sand in bed load and point bars.

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21. Conclusions

 The total estimated mineable resources of rock and gravel (and soil) within Vavuniya district in cubic meters are as follows:

Rock - 1.72 x 107 m3

Gravel & Soil - 9.08 x 106 m3

 DS Division wise estimated mineable resources of rock and gravel (and soil) within Vavuniya district in cubic meters are as follows:

DS Division Rock (m3) Gravel & Soil (m3)

Cheddikulam 2.40 x 105 1.09 x 106

Vavuniya South - Sinhala 1.42 x 107 1.24 x 106

Vavuniya - Tamil 2.73 x 106 6.42 x 106

Vavuniya North - Nedunkerni 8.80 x 104 3.28 x 105

Total 1.72 x 107 9.08 x 106

 Majority of large scale rock quarries and areas which are proposed to develop as large quarries are in the southern part of the district. In contrast the northern part of the district lacks large rock outcrops.

 All three type of gravel (and soil) occurrences can be observed throughout the district in all four DS divisions and most of them are mineable.

 River sand is very limited in the Vavuniya District since perennial rivers are not present in the area.

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22. Recommendations

 Proper mining methods should be applied when operating rock quarries. It is recommended to maintain proper bench cuttings to avoid steep surfaces in rock quarries.

 Below surface rock quarrying is proposed for the Vavuniya district, since the area lacks rock outcrops. Suitable mining methods should be followed when mining below surface rocks and filling the space after mining is strictly recommended. The mining license should be issued after proper investigation of socio‐environmental assessment and the availability of filling material.

 It is recommended to mine only the above ground surfaces (i.e. small hillocks) gravel and soil beds. A Proper socio‐environmental assessment should be done before starting the mining to minimize any adverse impact.

 Decisions should be taken to reserve potential areas of raw materials in the district for future uses.

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Acknowledgements

First and foremost, the author is grateful to Chairman, Director General, Senior Director (Geology) and the project coordinator for readily providing all facilities to carry out the survey successfully, within the specified time frame.

The kind co‐operation shown by the District Secretariat, all the Divisional Secretariats and Grama Niladari in Vavuniya is appreciated.

Sincere thank goes to Mr. Paditha Priyanga (Cartographer), Miss G.V.N. Sajeewani and Miss D.D. Upeksha for preparation of maps and database.

A special appreciation is offered to all members of the field crew including C.R. Welikanna (Trainee Geologist) and Saliya Abeysinghe (Driver) who engaged in hard field excursion with me.

Finally, all geologists and rest of the staff members of GSMB are acknowledged for helping in various ways during the entire field survey and compilation of the report.

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References

Cooray,P.G . 1984. An introduction to the Geology of Sri Lanka. National Museums of Sri Lanka. Second Revised Edition 1984.

Cooray,P.G . 2003. The Quaternary of Sri Lanka. Geological Survey and Mines Bureau. (Centenary Publication 1903-2003).

Geological Map of Mankulam – Kokilai (Sheet No. 4), 1:100,000 scale, published by Geological Survey and Mines Bureau, 2008.

Geological Map of Mulliyan – (Sheet No. 2), 1:100,000 scale, published by Geological Survey and Mines Bureau, 2008.

Geological Map of Silavaturai – Tantirimalai (Sheet No. 5), 1:100,000 scale, published by Geological Survey and Mines Bureau, 2009.

Geological Map of Talaimannar – Palampiddi (Sheet No. 3), 1:100,000 scale, published by Geological Survey and Mines Bureau, 2009.

Geological Map of Vavuniya – (Sheet No. 6A), 1:100,000 scale, published by Geological Survey and Mines Bureau, 2008.

Priyantha, A.A.C., de Silva, K.T.U.S. and Mayooran, D., 2010. Final report on the mineral resources in Vavuniya district (Under the integrated strategic environmental assessment (ISEA) study of Northern Province), unpublished report of Geological Survey and Mines Bureau.

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