URBAN REDEVELOPMENT AUTHORITY TERM CONTRACT FOR SOIL INVESTIGATION (URA/T/13/010) SOIL INVESTIGATION WORKS AT WEST COAST VALE

CONTENTS VOLUME I Page No. 1.0 INTRODUCTION 005 1.1 General 005

2.0 FIELD WORKS 006 2.1 General 006 2.2 Description of Field Investigation 006 2.2.1 Drilling 006 2.2.2 Undisturbed Sampling 006 2.2.3 Standard Penetration Testing 006 2.2.4 Rock Coring 007

3.0 LABORATORY TESTING 007 3.1 General 007 3.2 Code of Practice 007 3.3 Physical Properties 008 3.3.1 Moisture Content 008 3.3.2 Bulk and Dry Density 008 3.3.3 Atterberg Limit 008 3.3.4 Grain Size Analysis 008 3.4 Mechanical Properties 009

3.4.1 Unconsolidated Undrained (UU) Triaxial Test 009 3.4.2 Permeability Test By the Falling-Head Method 009 3.4.3 Unconsolidated Undrained (UU) Triaxial Test 009

3.5 Direct Shear Box Test 009 3.6 Summary of Laboratory Test Result for Soils 010

4.0 SOIL CLASSIFICATION 010 5.0 LIST OF GEOLOGICAL CROSS-SECTIONS 012 REFERENCES 013

Report No: ECGP 2531 URA ECON GEOTECH PTE LTD

3 URBAN REDEVELOPMENT AUTHORITY TERM CONTRACT FOR SOIL INVESTIGATION (URA/T/13/010) SOIL INVESTIGATION WORKS AT WEST COAST VALE

LIST OF TABLES

Table 1.1 Quantity of Field Works and Laboratory Tests 014 Table 2.1 Classification / Symbol of Soil and Rock Type 015 Table 2.2 Geological Stratigraphy of Singapore 016 Table 2.3 Identification and Description of Soils 017 Table 2.4 Weathering Classification of Soils / Rocks 019 Table 2.5 Plasticity Chart 020 Table 2.6.1 Classification of Clays/Silts from Shear Strength 021 Table 2.6.2 Classification of Clays/Silts from SPT results 021 Table 2.6.3 Classification of Sands from SPT Results 021

LIST OF FIGURES

Fig. 1 Illustration of Boring Work 022 Fig. 2 Illustration of Standard Penetration Test 023

APPENDICES APPENDIX A · Location Plan 024

· Borehole Location Plan 025

· As-built Borehole Locations 026

· Cross-Sections 027-028

· Legends for different soil and rock types 029

· Borehole Logs 030-039

· Core Photos 040

APPENDIX B · Laboratory Test Results of Physical & Mechanical Properties of Soil Samples 041-112

· Certificate of Accreditations 113-114

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Report No: ECGP 2531 URA ECON GEOTECH PTE LTD

4 1.0 INTRODUCTION

1.1 General On behalf of Urban Redevelopment Authority, Econ Geotech Pte Ltd has performed the Contract URA/T/13/010 Site Investigation Works for (WO 17). The field investigation for this project was carried out between 23rd January 2016 and 02nd February 2016. The works described in this report have been carried out as per the specifications and under the technical direction of the client. This report presents the soil investigation based on 5 boreholes. The particulars of this project are as follows: (a) Name of Project Site Investigation Works for Contract URA / T/13/010

(b) Location West Coast Vale (near AYE and Pandan River (c) Client Urban Redevelopment Authority (d) Main Contractor ECON Geotech Pte. Ltd. (e) Director Steven Ih Yeo (f) Project Manager Aung Moe (g) Period of Work Field Works 23rd January 2016 – 02nd February 2016

Laboratory Works and Report 03rd February 2016 – 23rd February 2016 (h) Scope of Work Field Works Boreholes 5 Locations Ø Laboratory Tests Moisture Content, Bulk & Dry Density, Grain Size Analysis (Sieving), Atterberg Limit Tests, Triaxial (UU) Tests, Direct Shear Box Tests, Falling Head Permeability Test, Unconfined Compression Tests

(Refer Table 1.1 for Quantities of Field and Laboratory Works)

5 2.0 FIELD WORKS

2.1 General The field works were carried out in accordance with BS 5930:1999 +A2:2010 “Code of Practice for Site Investigation” and / or as directed by the client. The Borehole Location Plan for proposed site investigation works is shown in Appendix-A. The as-built coordinates and reduced levels of the boreholes are also presented in respective borelogs in Appendix-A.

2.2 Description of Field Investigation 2.2.1 Drilling This investigation was performed using rotary drilling rig. A cutting tool was attached to the drilling rod to drill through the soils, which produces 100mm diameter borehole. Circulated mud water was pumped through the hollow rods into the hole to stabilize the borehole and to wash out the soil debris (resulted due to drilling) to the ground surface by pressure. Partial casing (100mmф) was used to stabilize the soil on top in the borehole apart from using mud circulation. Trial pits of size 1.0 x 0.8 x 1.0 m depth was dug manually at every borehole locations. The boreholes were terminated at the depths as suggested by the client. Illustration of boring works was shown in (Fig.1) During the investigation, a site bore log was done and kept by the geotechnical site supervisor to note down soil descriptions, stratum changes, SPT and coring field records.

2.2.2 Undisturbed Sampling Undisturbed samples (UD samples) were collected at the depth of 3m interval in the geologic formations, unless specified by the client. Before a sample was taken, the bottom of the borehole was properly cleaned. Each sample was then collected using a 75 mm diameter by 1000 mm long thin wall sampler tube driven by hydraulic push. Samples of very stiff to hard soil were collected by using Mazier sampler. Thin wall piston samplers were used for very soft to soft soil. After a sample was retrieved from borehole, it was immediately labeled and sealed with wax at both ends before sending to laboratory.

2.2.3 Standard Penetration Testing Standard Penetration Tests (SPT) is performed at 3.0m interval in all soil layers. Once the borehole reached the required test depth, the borehole was cleaned by flushing with water/mud before starting the test. The test was performed by using a split barrel type sampler with a 50.8 mm external and 34.9 mm internal diameter. The test was conducted in

6 six stages, where each stage consisted of driving the sampler 75 mm into the soil by using a free fall of 63.5 kg hammer (or monkey). The hammer was dropped from a height of 760 mm on to anvil connected to the sampler by rods. The number of blows required for each 75mm penetration was noted and the final N-value is reported as the total number of blows required to achieve the last 300 mm of penetration, the initial 150 mm of penetration being to seat the sampler and by-pass any disturbance. If, however, 100 blows were reached before a penetration of 300 mm was achieved, the test was stopped and the penetration achieved recorded.

2.2.4 Rock Coring An NMLC (triple tube0 diamond annular bit, fixed to the bottom of the outer rotating tube of a rotary core barrel cuts 52mm diameter cores, which is retained within the inner stationary tube of the core barrel and brought to the surface for examination and testing. All description and logging is in general accordance with BS 5930:1999 +A2:2010. besides linear core recovery, a determination of Rock Quality Designation (RQD, which is defied as percentage of rock recovered as sound lengths which are 100mm or more in length) as a quantitative measure of the fracture state of the rock is given. It is noted that the RQD is not the only criteria to assess the strength of the rock mass. Rock cores recovered were logged and subsequently delivered to geotechnical contractor’s office to be photographed. Upon completion of the photography and testing, the core boxes were delivered to Client’ designated office for storage.

3.0 LABORATORY TESTING 3.1 General The various laboratory tests were performed on undisturbed samples based on the testing schedule approved by the client/consultant. The tests related to mechanical properties were performed in the Econ Geotech Laboratory. The quantities of laboratory tests are summarized in Table 1.1.

3.2 Code of Practice The laboratory tests were performed in accordance with the British Standard Code of Practice BS 1377 (1990) and as per terms of accreditation under the Singapore Accreditation Council – Singapore Laboratory Accreditation Scheme. The summaries and detailed test results are presented in Appendix-B. The results are also presented in respective borehole logs.

7 3.3 Physical Properties 3.3.1 Moisture Content To measure moisture content, a weighed specimen is taken from an undisturbed sample and placed in a tin, where it is oven dried at 105-110◦C for 18-24 hours. The soil is weighted after the drying and the weight of water is calculated simply by subtracting the two values. The moisture content is then defined as the percentage of the weight of water over weight of dry soil.

3.3.2 Bulk and Dry Density The bulk density is the measured weight of a solid cylindrical soil specimen taken from an undisturbed sample divided by its volume. The dry density was calculated from bulk density and moisture content.

3.3.3 Atterberg Limit The liquid limit of a specimen is derived using the cone penetrometer method as to BS 1377. The plastic limit is defined as the moisture content of a specimen at the point where it can be satisfactorily rolled into a 3mm diameter thread with just starting to crumble. The soils’ plasticity index is then derived by subtracting the plastic limit from the liquid limit.

3.3.4 Grain Size Analysis The grain size analysis has been carried out utilizing both sieve and hydrometer analysis. The sieve analysis was carried out by wet sieving method in which the material was first washed through a 2 mm test sieve nested in a 63 mm test sieve. The soils retained in the sieves were then dried in an oven. The dried soils were then sieved by dry sieving by passing the soils through a series of square mesh sieves, which become progressively finer down to 63 mm mesh. Each fraction thus collected was then weighed and the percentage retained on each sieve was calculated by dividing individual weights by the total sample weight. The soils passing through 63 mm mesh was analyzed by sedimentation using hydrometer method. The hydrometer method involves measuring the rate of settlement of fine particles suspended in a solution. Utilizing the principle of Stokes’ law, particle size can be directly related to its rate of settlement in a fluid such as water. From this process, the particle diameter and percentage finer is calculated.

8 3.4 Mechanical Properties 3.4.1 Unconsolidated Undrained (UU) Triaxial Test This test is generally performed as a set of three single stage tests (UU). However, if the sample is not enough, the test is conducted using two or single (multistage) specimen. The general testing procedure is as explained below. With the three single stage tests, three specimens were extracted from a single undisturbed sample, and was trimmed and cut to a length to diameter ratio is about two. The specimens were then weighed before putting the rubber membrane and placing into triaxial cell. Cell pressures of 0.5sv, sv, and 2sv (where sv is total overburden pressure at the sampling depth) were applied to the three specimens followed by shearing under undrained conditions at a constant rate of strain (usually 2% per minute). Axial load and displacement were recorded at regular intervals until a maximum deviator stress, or 20% of strain is reached. For tests with two specimens, cell pressure of sv and 2sv were used.

3.4.2 Permeability Test by the Falling-Head Method Falling head permeability test was conducted to measure the permeability of the soil. The permeability of a soil is a measure of its capacity to allow the flow of a fluid through it.

3.4.3 Unconfined Compression (UC) Test on Rock Core Unconfined compression test was conducted on selected rock core sample to assess the strength characteristic. This is determined by statically loading the cylinder of rock to failure, the load being applied across the upper and lower faces of the sample. The test was conducted in accordance with ASTM D2938-95.

3.5 Direct Shear Box Test The direct shear test measures peat and residual direct shear strength as a function of the stress normal to the plane of shearing. The standard deals with the laboratory testing for the determination of the basic shear strength parameters and the surface characteristic of a discontinuity that controls the shear strength. If the surface characteristic of a discontinuity that controls the shear strength are determined, an accurate description should be made, including type and roughness of the joint, type and thickness of fill material, and presence of water in the joint.

9 3.6 Summary of Laboratory Test Results for Soils Laboratory tests were generally performed in accordance with the British Standards Code of Practice BS 1377 (1990). The tests were carried out on undisturbed samples to determine the physical, mechanical and chemical properties. Details results of physical and mechanical properties of soil for each geological classification are presented together with borehole logs in Appendix-B. Summaries of test results are also presented respectively.

4.0 SOIL CLASSIFICATION The soil classification is based on the geological classification and British classification system as given in Appendix-A.A The consistencies of clay/silt and relative densities of sand have been classified according to the (BS5930: 1999+A2:2010). Classification of sand, clay and silt from SPT and Shear Strength are presented in (Table 2.6.1 to 2.6.3).

4.1 Description of Soil under Present Investigating Area Based on the borehole data and in-situ tests results obtained from the boreholes, the underlying subsoil can be sub-divided into the following layers: - FILL - KALLANG FORMATION - JURONG FORMATION

4.1.1 FILL Fill is inhomogeneous material made by man. The fill layer consists of multi-colored, soft to stiff, reddish brown, light yellowish brown and light whitish grey, slightly gravelly slightly sandy to sandy CLAY/ SILT with concrete pieces and bricks. Fill layers were observed in all of the boreholes. Thickness of the Fill layers varies from 5.00m (BH1, BH2 and BH5) to 9.00m (BH3) with SPT N-value varied from 3 (BH2) to 10 (BH3). . 4.1.2 KALLANG FORMATION 4.1.2.1 Transitional Member (Kt) Estuarine Peaty/Organic SILT/CLAY/SAND (E) The Kallang Formation – Transitional or Estuarine Member (E) was observed only in four (4) boreholes (BH1, BH2, BH4 and BH5). The Estuarine Peaty/ Organic layer consists of s very soft to firm, dark grey to black, brown to dark grey, slightly gravelly slightly sandy CLAY/ Peaty CLAY. Thickness of the Estuarine Peat/ Organic layers varies from 2.50m (BH2) to 5.50m (BH5) with SPT N-value varied from 1 (BH5) to 4 (BH2).

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4.1.2.2 Fluvial SAND (F1) The Kallang Formation – Alluvial Member (Fluvial SAND) was observed in one (1) borehole (BH5). This Alluvial Member (F1) is composed of loose, dark grey, slightly silty SAND.

4.1.3 JURONG FORMATION (J) The soil and rock samples, retrieved from all of the five (5) boreholes indicated the occurrence of SANDSTONE and SILTSTONE of the Jurong Formation. There were evidences of Residual Soil of Jurong Formation (S 5) to Moderately Weathered Sedimentary Rocks (S 2) at these boreholes.

4.1.3.1 The Residual Soils (S 5) of the Jurong Formation was recorded in only one (1) borehole (BH1). It was consisted of stiff to very stiff, whitish grey spotted yellowish brown and reddish brown, slightly sandy CLAYSILT. Thickness of (S 5) layers was 6.00m (BH1) with SPT N-value of 11 to 17 (BH1).

4.1.3.2 The Completely Weathered Sedimentary Rocks (S 4) were composed of dense to very dense, whitish grey mottled pink, light yellowish brown, slightly gravelly silty fine to coars SAND; very dense dark grey to grey, sandy GRAVEL; very stiff to hard, light grey, light greenish grey, slightly gravelly to gravelly, slightly sandy to sandy SILT/ CLAY. The original sedimentary texture of the rock was well preserved and obviously noticeable. This layer was observed in all five (5) boreholes (BH1, BH2, BH3, BH4 and BH5), with SPT N- value varies from 44 (BH5) to 100 (BH1, BH2, BH3, BH4). Measurable thickness of the Completely Weathered Sedimentary Rocks of the Jurong Formation (S 4), excluding of the inferred layers as core loss in the core samples, ranges from 10.45m (BH1) to 26.42m (BH4).

4.1.3.3 The Highly Weathered Sedimentary Rocks (S 3) of the Jurong Formation was encountered in one (1) borehole (BH5) as alternation with Moderately Weathered (S 2) layers. It was composed of weak to medium strong, light grey to grey, Conglomeratic SANDSTONE as rock cored samples. Measurable thickness of the Highly Weathered Sedimentary Rocks of the Jurong Formation (S 3) was 3.00m (BH5).

4.1.3.4 The Moderately Weathered Sedimentary Rocks (S 2) of the Jurong Formation was was not encountered until the termination depth.

11 4.1.3.5. The Slightly Weathered Sedimentary Rocks (S 1) and The Fresh Sedimentary Rocks ( S 0)of the Jurong Formation was not encountered until the termination depth.

5.0 LIST OF GEOLOGICAL CROSS-SECTIONS Geological cross-sections showing the soil strata profile at the borehole locations are presented in Appendix-A.

SECTION BOREHOLES

1 BH1 – BH3 – BH5

2 BH4 – BH3 – BH2

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REFERENCES

1. BS 5930: 1999. +A2:2010“Code of Practice for Site Investigations”, British Standard. 2. SS EN 1997-2 “Eurocode 7 - Geotechnical Design- Part2: Ground Investigation and Testing”. 3. EN ISO 14688-1 “Geotechnical Investigation and Testing: Identification and Classification of Soil – Part 1: Identification and Description”. 4. EN ISO 14688-2 “Geotechnical Investigation and Testing: Identification and Classification of Soil – Part 2: Principle for a Classification”. 5. EN ISO 14689-1 “Geotechnical Investigation and Testing: Identification and Classification of Rock – Part 1: Identification and Description”. 6. EN ISO 22476 “Geotechnical Investigation and Testing”. 7. Singapore National Annex (NA) to SS EN 1997-2. 8. Braja M. Das, 1994. Principles of Geotechnical Engineering, Third Edition. PWS Publishing Company, Boston 9. Coduto, Donald P, 1994. Foundation Design: Principles and Practices. Pentice-Hall, New Jersey. 10. Karl Terzaghi, Ralph B. Peck and Gholamreza Mesri, 1996. Soil Mechanics in Engineering Practice, Third Edition. 11. Michael Carter and Stephen P Bentley, 1991. Correlations of Soil Properties. Pentech Press, London. 12. P.W.D., 1976. “The Geology of the Republic of Singapore”, Public Works Department, Singapore. 13. DSTA, 2009. “Geology of Singapore”, 2nd ed., Defense Science and Technology Agency, Singapore.

13 SOIL INVESTIGATION WORKS AT WEST COAST VALE TABLE 1.1 QUANTITY OF FIELD WORKS AND LABORATORY TESTS In Situ Test & Sampling Soil Drilling Work Soil Laboratory Test DS Undistrubed Sample

Borehole No. Total MZ/T Soil Rock Starting Finished Trial Pit Size Drilling SPT TW PS hick UU CU

Drilling Coring UCS LL/PL (Sieve) Depth wall (Hydro) Box Test Grain Size Grain Size Permeability Bulk Density Direct Shear Consolidation (Falling Head) Water Content Particle Density Date Date (mxmxm) (m) (m) (m) no. no. no. no. no. no. no. no. no. no. no. no. no. no. no. no.

BH1 23-Jan-16 27-Jan-16 1.0x1.0x1.0 24.45 24.45 - 8 2 - 2 4 4 - - 2 2 1 - - - 1 1 14

BH2 30-Jan-16 02-Feb-16 1.0x1.0x1.0 21.45 21.45 - 7 2 - 2 4 4 - - 2 3 3 - - - - 1

BH3 30-Jan-16 02-Feb-16 1.0x1.0x1.0 21.30 21.30 - 7 2 - 2 4 4 - - 2 4 2 - - - - 2

BH4 27-Jan-16 01-Feb-16 1.0x1.0x1.0 36.42 36.42 - 12 2 - 2 4 4 - - 3 4 1 - - - - 2

BH5 23-Jan-16 28-Jan-16 1.0x1.0x1.0 33.00 30.00 3.00 10 2 - 2 4 4 - - 2 2 2 - - 1 - 2

Total 136.62 133.62 3.00 44 10 - 10 20 20 - - 11 15 9 - - 1 1 8

Trial Pit ~ Hand auger from GL-1.0 to 2.0m SPT = Standard Penetration Test TW= Thin Wall Soil Sample, PS= Piston Soil Sample, MZ= Mazier Sample LL/PL= Atterberg Limits Test SOIL & ROCK GEOLOGICAL REFERENCE GENERAL DESCRIPTION TYPE FORMATION (PWD, 1976)

B BEACH (Littoral) Sandy, sometimes silty, with gravels, coral and KALLANG Littoral, possibly shells also part of all other members & TEKONG

E ESTUARINE Peats, peaty and organic clays, organic sands KALLANG Transitional, (Transitional) possibly part of Alluvial and Marine.

F FLUVIAL Sands, silty sands, silts and clays KALLANG Alluvial, possibly (Alluvial) part of all other members and TEKONG.

F1 Predominantly granular soils including silty Bed of Alluvial Member of sands, clayey sands and sandy silts KALLANG

F2 Cohesive soils including silty clays, sandy Bed of Alluvial Member of clays and clayey silts KALLANG

M MARINE Very soft to soft blue or grey clay KALLANG Marine Member

O OLD ALLUVIUM Very weak to weak beds of sandstone and OLD ALLUVIUM mudstone. See C-5 for weathering classification

FC FORT CANNING A colluvial deposit of boulders in a soil matrix. Not shown in PWD (1976) BOULDER BED The matrix is typically a hard silty clay, but (also known as can be granular. The material is largely derived S3, Bouldery Clay from the rocks and weathered rocks of the or Boulder Bed) Jurong Formation

S SEDIMENTARIE Sandstones, siltstones mudstones, JURONG Tengah, Rimau, S (Rocks & conglomerate and limestone. The rock Ayer Chawan and Queenstown associated soils) has been subjected to a varying degree of Facies (plus the Pandan metamorphism. Limestone, which was not identified in PWD (1976)

G GRANITE (Rock Granitic rocks, including granodiorite, BUKIT TIMAH GRANITE and associated adamellite and granite. Residual soils)

C-3 Classificatiion/ Symbol of Soil and Rock Type

15 Geological Time Series/Stage Description of stratum Time Bp- Stratum Era Period Epoch Formation Symbol Particular Origin year Zone First Au (O1) Consists mainly decomposed organic Deposit of limnetic brackish Organic Clay material. Very soft & high water content. water

First Au(S1) Poor graded medium grain loose sand with Deposited at beach and

Sand some shell fragments. shallow water depth of sea. 6000 Marine Au(M) Very soft high water content and high Seabed deposit at 5-30m depth - Clay plasticity clay. drowned valley. 10000 Upper Alluvium First Cohesive Au(C) Very soft high water content clayey silt with Deposit of limnetic-half soil sand. brackish water. Second Organic Au(O2) Very soft decomposed organic matter with Deposit of limnetic-half Clay clay. Brackish water. Second Au(S2) Well graded sand with some organic. Deposit at shallow water Sand depth.. Holocene Brown AL(B) Lower water content stiff clay. Thickness Alteration by weathering Clay varies at each location. oxidation. 11000 Third AL(S1) Medium dense fine to medium grained sand Deposit at shallow sea water - Sand depth or beach. 15000

Lower Marine AL(M) Soft and high plasticity homogeneous clay Seabed deposit at 5-30m depth Clay with shell fragments. drowned valley. Quarter Lower nary Alluvium Second Cohesive AL(C) Soft to firm high plasticity clayey silt with Deposit of limnetic-half Soil fine sand. brackish water. Third AL(O) Soft low water content organic clay. Deposit at shallow water depth. Organic Clay Fourth AL(S2) Well graded sand with some gravel and Shallow seabed deposit. Sand organic material Weathered Zone OA(W) Irregular alternating layers of well graded Weaken and alteration by Approx

Cenozoic sandy soil and clayey silt. Very Dense and weathering/ oxidation. 3.5-5.0 Old 4 Pleistocene hard by cementation. x 10 Alluvium Cemented Zone OA(C) Materials is very hard & dense by chemical/ diagenesis.

Weathered Zone Bc(W) Very hard reddish brown clay with various Produce of fault as fault clay Boulder sizes of strong sandstone boulder. Size of and fault breccia and cemented Tertiary__ Unknown__ Clay Cemented Zone Bc(C) boulder ranges from 10-45cm. during some geological period. Residual J(R) Constituted of alternating sandstone, Wholly decomposed material Approx Soil mudstone and conglomerate. Limestone by weathering. 2.0x108 developed as thin layers. Many fault zones Completely J(C) Decomposed material by are found and material near the granite area - Weathered Zone weathering. Jurassic- Initial is disturbed. Thermal metamorphism occurs 8 Highly J(H) near the granite zone. Weak and friable material by 2.1x10 Weathered Zone weathering Jurong Formation Moderately J(M) Materials weakened near joint Weathered Zone surface by weathering. Slightly J(S) Many joints developed with Late Weathered Zone some weathering at joint

Mesozoic surface. Fresh Zone J(F) Strong massive rock.

Residual G(R Coarse-grained granodiorite and biotite Wholly decomposed material Approx Soil granite. Contains porphyrite and to soil. 2.1x108 Triassic Middle Completely G(C) lamprophyre as dike. Two types of fault Decomposed weak material by Weathered Zone system are found to develop. weathering. -

Highly G(H) Weak and friable material by 8 Bukit 2.2x10 Weathered Zone weathering. Timah Granite Moderately G(M) Material is weak near the joint. Weathered Zone Slightly G(S) Joints developed with some Initial Weathered Zone weathering at joint surfaces. Fresh Zone G(F) Strong massive rock.

C-2 Geological Stratigraphy of Singapore (M.W. TAN & A.WADA, 11TH S.E ASIAN GEOTECH. CONF., 4-8 MAY, 1993)

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soils soils Very coarse Very Coarse soils Coarse (over about 65% sand and gravel sizes) Fine Soils (over about 35 (over % aboutsilt and sizes) clay 35 Organic Soil Soil Organic

C-4 Identification and Description of Soil (BS 5930, 1999)

17 Table 3.2 Identification and description of soils (continued)

PRINCIPAL Visual identification Minor constituents Stratum name Example descriptions SOIL TYPE BOULDERS Only seen complete in pits or exposures Shell fragments, RECENT Loose brown very sandy sub- COBBLES Often difficult to recover whole from boreholes pockets of peal, DEPOSITS, angular fine to coarse flint gypsum crystals, flint GRAVEL with small pockets(up Easily visible to naked eye: particle shape can GRAVEL gravel, fragments of ALLUVIUM, to 30mm)of clay. (TERRACE be described: grading can be described. brick, rootlets, plastic GRAVELS) bags etc Medium dense light brown gravelly clayey fine SAND, Visible to naked eye: no cohesion when dry: Gravel is fine (GLACIAL SAND grading can be described. DEPOSITS) using terms such as; WEATHERED BRACKLESHAM CLAY, with rare Stiff very closely sheared orange mottled brown slighlty gravelly CLAY. Gravel is fine Only coarse silt visible with hand lens; exhibits with occasional LIAS CLAY, and medium of rounded little plasticity and marked dilatancy: slightly quartzite. (REWORKED SILT granular or silky to the touch; disintegrates in WEATHERED LONDON CLAY) water; lumps dry quickly; possesses cohesion but can be powdered easily between fingers with abundant/frequent/ numerous

EMBANKMENT Intermediate in behaviour between clay and CLAY/SILT FILL, silt. Slightly dilatant %defined on a site or material specific basis TOPSOIL, or subjective Firm thinly laminated grey CLAY with closely spaced thick laminae of sand (ALLUVIUM)

MADE GROUND Dry lumps can be broken but not powdered OR GLACIAL between the fingers; they also disintegrate DEPOSITS? etc. under water but more slowly than silt; smooth CLAY to the touch; exhibits plasticity but no dilatancy; sticks to the fingers and dries slowly; shrinks Plastic brown clayey appreciably on drying usually showing cracks. amorphous PEAT (RECENT DEPOSITS)

Notes a) Or described as coarse soil depending on mass behaviour d) Gravelly sandy and/or silty or clayey

b) Or described as fine soil depending on mass behaviour e) Gravelly and/ or sandy

c) %coarse or fine soil type assessed excluding cobbles and boulders f) Gravelly of sandy

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Table 2.5 WEATHERING CLASSIFICATION OF SOILS / ROCKS

Weathering Classification (Bukit Timah Granite and Gombak Norite) Grade Basis for assessment Intact strength, unaffected by weathering. Not broken easily by hammer – rings G(0) when struck. No visible discoloration. Not broken easily by hammer – rings when struck. Fresh rock colors generally G(1) retained but stained near joint surfaces. Cannot be broken by hand. Easily broken by hammer. Makes a dull or sight ringing G(2) sound when struck with hammer. Stained throughout. G(3) Core can be broken by hand. Does not slake in water. Completely discolored. Original rock texture preserved can be crumbled by hand. Slakes in water. G(4) Completely discolored. Original rock structure completely degraded to a soil with none of the original fabric G(5) remains. Can be crumbled by hand.

Weathering Classification for Jurong Formation (Except Pandan Limestone) Grade Basis for assessment

S(0) Intact strength, unaffected by weathering

S(1) Slightly weakened, slight discoloration, particularly along joints. Considerable weakened & discolored, but larger pieces cannot be broken by hand. S(2) RQD is generally >0, but RQD should not be used as the major criterion for assessment. Core can be broken by hand or consists of gravel size pieces. Generally highly to very highly fractured, but majority of sample consists of lithorelics. RQD generally S(3) = 0, but RQD should not be used as major guide for assessment. For siltstone, shale, sandstone, quartzite and conglomerate, the slake test can be used de differentiate between Grade IV (does not slake). Rock weathered down to soil-like material, but bedding intact. Material slakes in S(4) water S(5) Rock degraded to a soil in which none of the original bedding remains.

Weathering Classification for Old Alluvium Indicative SPT, Class Classifier Characteristics Blow/300mm* A Unweathered Original strength >50(cannot usually be penetrated by CPTs B Partially Weathered Slightly reduced strength with 20t load capacity)

C Distinctly weathered Further weakened 30 to 50 Greatly weakened, often D Destructured 10 to 30 mottled, bedding disturbed E Residual No bedding remains <10 * The SPT result should not be used in isolation to assess weathering.

19 20

Undrained Shear Strength (kPa) Consistency < 20 Very Soft 20 – 40 Soft 40 – 75 Firm 75 – 150 Stiff 150 – 300 Very Stiff > 300 Hard

Table 2.6.1 Classification of Clays/Silts from Shear Strength (BS5930: 1999)

Approximate Relation of Consistency to SPT N-Value (blows/300mm of penetration) Consistency < 2 Very Soft 2 – 4 Soft 4 – 8 Firm 8 – 15 Stiff 15 – 30 Very Stiff > 30 Hard

Table 2.6.2 Classification of Clays/Silts from SPT results (Terzaghi and Peck)

Approximate Relation of Relative Density to SPT N-Value (blows/300mm of penetration) Relative Density

< 4 Very Loose 4 – 10 Loose 10 – 30 Medium Dense 30 – 50 Dense > 50 Very Dense

Table 2.6.3 Classification of Sands from SPT results (BS5930: 1999)

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Fig. 1. Illustration of Boring Work

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Fig. 2. Illustration of Standard Penetration Test

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APPENDIX - A

BOREHOLE LOCATION PLAN, GEOLOGICAL INFROMATION AND BOREHOLE DATA

· LOCATION PLAN

· BOREHOLE LOCATION PLAN

· AS BUILT BOREHOLE LOCATION PLAN

· CROSS - SECTIONS

· LEGENDS FOR DIFFERENT SOIL AND ROCK TYPES

· BOREHOLE LOGS

· CORE PHOTOS

AYER

RAJAH FABER WALK

FABER HILL EXPRESSWAY

FABER WALK Sheng

Hong FABER Temple SITE SOLD IN AUGUST 2015

Pandan Gardens LAND RAJAH Leisure PARCEL FUTURE park DEVELOPMENT THE INFINITI Future Road by others

FUTURE DEVELOPMENTS Sungei Pandan

Pandan Gardens Park Connector Future Road by others BOTANNIA

COAST VALE

WEST

WEST WEST

COAST HONG COAST

COAST LEONG

GARDEN PARK MONTEREY WEST ROAD PARK PARK CONDOMINIUM 4.5m D.R.

L O C A T I O N P L A N S C A L E : 1 : 5 0 0 0

24 Sungei Pandan

B O R E H O L E L O C A T I O N P L A N S C A L E : 1 : 2 0 0 0

25 26 SECTION1 : BH1 , BH3 & BH5

GEOLOGICAL CLASSIFICATION

JURONG FORMATION KALLANG FORMATION

Drawn By: Date: VERTICAL SCALE - 1:300 Checked By: Date: HORIZONTAL SCALE - NOT TO SCALE

27 SECTION1 : BH4 , BH3 & BH2 GEOLOGICAL CLASSIFICATION

JURONG FORMATION KALLANG FORMATION

Drawn By: Date: VERTICAL SCALE - 1:300 Checked By: Date: HORIZONTAL SCALE - NOT TO SCALE

28 29

Econ Geotech Pte Ltd ECON GEOTECH PTE LTD

30 ECON GEOTECH PTE LTD

31 ECON GEOTECH PTE LTD

32 ECON GEOTECH PTE LTD

33 ECON GEOTECH PTE LTD

34 ECON GEOTECH PTE LTD

35 ECON GEOTECH PTE LTD

36 ECON GEOTECH PTE LTD

37 ECON GEOTECH PTE LTD

38 ECON GEOTECH PTE LTD

39 40

BH5 CR1-CR3

CLIENT :URBAN REDEVELOPMENT AUTHORITY

PROJECT :SOIL INVESTIGATION WORKS AT WEST COAST VALE

APPENDIX – B

LABORATORY TEST RESULTS

· SUMMARY OF LAB TEST RESULTS OF PHYSICAL AND MECHANICAL PROPERTIES OF SOIL SAMPLES

· DETAIL TEST RESULTS OF PHYSICAL AND MECHANICAL PROPERTIES OF SOIL SAMPLES

¨ Results of Water Content & Bulk/Dry Density

¨ Results of Sieve Analysis Tests

¨ Results of Atterberg Limit Tests

¨ Results of Triaxial (UU) Tests

· CERTIFICATE OF ACCREDIATIONS

41 42 43 44 45 46 47 48