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GEOTECHNICAL INVESTIGATION REPORT
No. 105 Cudgegong Road
Rouse Hill, NSW
Prepared for
Weyand Pty Ltd
Reference No. ESWN-PR-2017-118
26th
June 2017
Geotechnical Engineering Services
- Geotechnical investigation
- Site classification - Geotechnical design - Excavation methodology and monitoring plans
- Footing inspections - Slope stability analysis - Landslide risk assessment
- Environmental Investigation
ESWNMAN PTY LTD ABN 70 603 089 630
PO Box 6, Ashfield NSW 1800
Telephone +61 2 7901 5582 Email [email protected] http://www.eswnman.com.au
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Geotechnical Investigation Report 26th June 2017
CONTROLLED DOCUMENT
DISTRIBUTION AND REVISION REGISTER
Revision Details Date Amended By
00 Original 26/06/2017
©ESWNMAN Pty Ltd (ESWNMAN) [2014].
Copyright in the drawings, information and data recorded in this document (the
information) is the property of ESWNMAN Pty Ltd. This document and the information
are solely for the use of the authorised recipient and may not be used, copied or reproduced
in whole or part for any purpose other than that for which it was supplied by ESWNMAN.
ESWNMAN makes no representation, undertakes no duty and accepts no responsibility to
any third party who may use or rely upon this document or the information.
Author: Jiameng Li ......................................................
Signed: ........................................................................
Date: 26/06/2017 ......................................................
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TABLE OF CONTENTS
1. INTRODUCTION .............................................................................................................. 6
1.1 Available Information .................................................................................................................. 6
1.2 Proposed Development................................................................................................................. 6
1.3 Scope of Work .............................................................................................................................. 7
2. SITE DESCRIPTION ......................................................................................................... 8
3. LOCAL GEOLOGY ............................................................................................................. 9
4. METHODOLOGY OF INVESTIGATION ........................................................................ 9
4.1 Pre-fieldwork ............................................................................................................................... 9
4.2 Borehole Drilling .......................................................................................................................... 9
4.3 Point Load Strength Index (PLSI) Test ..................................................................................... 10
4.4 Laboratory Test ......................................................................................................................... 10
5. RESULTS OF INVESTIGATION ................................................................................... 10
5.1 Surface Conditions ..................................................................................................................... 10
5.2 Subsurface Conditions ............................................................................................................... 10
5.3 Groundwater .............................................................................................................................. 11
5.4 Laboratory Test ......................................................................................................................... 12
6. GEOTECHNICAL ASSESSMENTS ................................................................................ 13
6.1 Site Characterisation and Classifications .................................................................................. 14
6.2 Excavation Conditions ............................................................................................................... 14
6.3 Excavation Support / Stability of Basement Excavation ........................................................... 15
6.4 Earth Retaining Structures ........................................................................................................ 16
6.5 Foundations ................................................................................................................................ 18
6.6 Salinity Assessment .................................................................................................................... 19
6.7 Groundwater Management ........................................................................................................ 20
6.8 Earthworks and Material Reuse ................................................................................................ 20
6.9 Preliminary Comments on Pavement Subgrade........................................................................ 21
7. CONCLUSIONS AND RECOMMENDATIONS ............................................................ 22
8. LIMITATIONS ................................................................................................................ 23
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LIST OF TABLES
Table 1 - Summary of Subsurface Conditions 11
Table 2 - Results of Laboratory Test on Soil Samples 13
Table 3 - Recommended Safe Excavation Batters 16
Table 4 - Preliminary Geotechnical Design Parameters for Retaining Walls 17
Table 5 - Preliminary Coefficients of Lateral Earth Pressure 17
Table 6 - Preliminary Geotechnical Foundation Design Parameters 19
LIST OF APPENDICES
APPENDIX A SITE LOCATION PLAN
APPENDIX B SITE PHOTOGRAPHS
APPENDIX C ENGINEERING BOREHOLE LOGS AND EXPLAINATORY NOTES
APPENDIX D CORE PHOTOGRAPHS
APPENDIX E RESULTS OF POINT LOAD STRENGTH INDEX (PLSI) TEST
APPENDIX F RESULTS OF LABORATORY TEST
APPENDIX G LIMITATIONS OF GEOETCHNICAL INVESTIGATION
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REFERENCES
1. Australian Standard – AS 1726-1993 Geotechnical Site Investigation.
2. Australian Standard – AS 2870-2011 Residential Slabs and Footings.
3. Australian Standard – AS 2159-2009 Piling - Design and Installation.
4. Australian Standard – AS 3798-2007 Guidelines on Earthworks for Commercial and
Residential Developments.
5. Australian Standard – AS 1170.4-2007 Structural Design Actions – Part 4:
Earthquake actions in Australia.
6. „NSW WorkCover: Code of Practice – Excavation‟ March 2000.
7. Pells, P.J.N, Mostyn, G. & Walker B.F., “Foundations on Sandstone and Shale in the
Sydney Region”, Australian Geomechanics Journal, 1998.
8. Austroads – “Pavement Design – A Guide to the Structural Design of Road
Pavements”, 2004.
9. Sydney Water, “Technical Guidelines for Building over and adjacent to Pipe Assets”,
October 2015.
10. Groundwater Management Information - Fact Sheet 1: Groundwater and the Sydney
Coastal Region.
11. The Western Sydney Regional Organisation of Councils (WSROC), “Western
Sydney Salinity Code of Practice”, March 2003 (Amended January 2004).
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1. INTRODUCTION
ESWNMAN Pty Ltd (ESWNMAN) was commissioned by Weyand Pty Ltd to undertake a
geotechnical investigation at No. 105 Cudgegong Road, Rouse Hill, NSW 2155 in a
Professional Services Agreement referenced ESWN-PP-2017-113 Rev A and dated 18th
April 2017. The site investigation was carried out on the 29th of May 2017.
The purpose of the investigation was to assess the feasibility of the site in geotechnical
prospective for a proposed residential development.
This report presents results of the geotechnical investigation, interpretation of test results,
and geotechnical assessment, and provides comments on geotechnical related issues and
recommendations for the proposed development.
1.1 Available Information
The following information was provided to ESWNMAN prior to the fieldwork:
Architectural drawings titled “Residential Development, 105 Cudgegong Road,
Rouse Hill” prepared by Dreamscapes Architects, referenced Project No. 17003,
drawing nos. A101, A201 and A213 inclusive, A310, A311, A320 & A321, dated
6th June 2017; and
A survey plan titled “Plan of Detail & Levels over Lot 80 in D.P. 208203 Known as
No. 105 Cudgegong Road, Rouse Hill” prepared by Mepstead & Associates,
referenced drawing No. 5442-DET1_A, Issue A and dated 16th March 2016.
1.2 Proposed Development
The design drawings provided indicated that the proposed development will include the
demolition of existing building at 105 Cudgegong Road and construction of the following:
Subdivision of site into three blocks, identified as Lots A, B & C;
Proposed four storey residential building with two basement levels in Lot A;
Proposed four storey residential building with one & two basement levels in Lot B;
Proposed roads within the site.
The site is bounded by the following properties and infrastructure:
East: Carriageway and road reserve of Cudgegong Road;
South: Adjoining property at 95 Cudgegong Road;
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West: Adjoining properties at 84 Tallawong Road, and 100 Macquarie Road; and
North: A two storey brick house at Lot 81 in DP 208203.
Based on existing ground elevations as indicated in a survey plan and proposed Finished
Basement Floor Levels (FFLs), the following depths of excavation are expected:
Lot A: Proposed FFL of RL61.000m for Lower Ground Level and RL58.000m for
Basement Level for building block A, the excavation depth is estimated to be
between 3.0m and 6.0m approximately;
Lot B: Proposed FFLs of RL62.000m for Basement Level 2 and RL64.750m for
Basement Level 2 for building block B, the excavation depth is estimated to be
between 3.0m and 7.0m approximately.
The following approximate setbacks were proposed from the basement wall:
21.5m from existing electricity transmission easement to the east;
6.0m from site southern boundary;
15.1m from site western boundary; and
15m from site northern boundary.
1.3 Scope of Work
The geotechnical investigation involved machine drilling of four boreholes using Han-Jin
8D type drilling rig and supervised by an experienced Geotechnical Engineer from
ESWNMAN, including the following:
Collection and review of Dial-Before-You-Dig (DBYD) plans;
A site walkover to assess site accessibility and surface conditions, identify relevant
site features and nominate borehole locations;
Drilling of four boreholes, identified as BH1 and BH4 inclusive, using Han-Jin 8D
type drilling rig;
Performing of Standard Penetration Tests (SPT) within soils to determine strength
of the materials encountered;
Geotechnical logging of rocks and soils retrieved from boreholes by an experienced
Geotechnical Engineer;
Collection of soil and rock samples during drilling;
Reinstatement of site with soil cuttings from boreholes;
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Point Load Strength Index (PLSI) Test on selected rock core samples;
Laboratory test undertaken by a NATA accredited laboratory, including Salinity
classification (Electrical Conductivity), aggressivity test (pH, Sulfate and Chloride),
and Exposure Classification.
The approximate locations of boreholes completed are shown on a site location plan as
included in Appendix A of this report.
Selected site photographs recorded during site investigation are provided in Appendix B.
2. SITE DESCRIPTION
The site is located within Blacktown City Council area, approximately 35km to the
northwest of Sydney CBD, approximately 3.1km to the northeast of Schofields Railway
Station and Blacktown-Richmond Railway Line, 600m to the west of Rouse Hill Regional
Park, and approximately 320m to the north of an unnamed tributary of the First Ponds
Creek.
The site is a rectangular-shaped land identified as Lot 80 in Development Plan (DP)
208203, with an approximate area of 2.023 hectares.
The existing building consists of a two-storey brick house. During site investigation, no
information was available on the foundation type of the existing building at the subject site.
However, based on our observations, it is inferred the existing building is likely to be
supported by shallow type foundations.
Based on the survey plan referenced in Section 1.1, the site the highest ground being at an
elevation of RL70.0m within middle portion of the site where the existing building is
located. Ground slopes slightly towards the southwest and the east. The ground elevations
vary approximately between RL60.50m and RL61.78m along the site western boundary, to
approximately between RL59.60m and RL62.0m along the site eastern boundary.
The information provided and our site observation, a 30.48m wide existing electricity
transmission easement (Overhead Power Lines) is present within the front portion of the
site and runs in a northwest-southeast direction.
Selected site photographs recorded during site investigation are provided in Appendix B.
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3. LOCAL GEOLOGY
Reference to the Penrith 1:100,000 Geological Series Sheet 9030 (Edition 1), dated 1991,
by the Geological Survey of New South Wales, Department of Minerals and Energy,
indicates the site is located within an area underlain by Triassic Age Bingelly Shale (Rwb)
of the Wianamatta Group. The Bringelly Shale is described as “Shale, carbonaceous
claystone, claystone, laminate, fine to medium-grained lithic sandstone, rare coal and tuff”.
Results of the investigation provided in Section 5.2 confirmed the published geology.
4. METHODOLOGY OF INVESTIGATION
4.1 Pre-fieldwork
Prior to the commencement of fieldwork, a site Safety Work Method Statement (SWMS)
was prepared, which identifies potential hazards associated with Occupational Health,
Safety and Environment aspects of the fieldwork and various control measures to be
implemented to mitigate the hazards, which are likely to encounter on site during execution
of fieldwork.
A „Dial Before You Dig‟ (DBYD) underground services search, which forms a part of the
SWMS, was also conducted with plans reviewed prior to the mobilisation.
4.2 Borehole Drilling
A total of four(4) boreholes were completed during site investigation. Boreholes BH1, BH2,
BH3 and BH4 were drilled to an approximate final depth of 4.6m, 5.0m, 7.0m and 9.0m
respectively below the existing ground level (BGL) using Tungsten Carbide (TC) Bit
technique and followed by rock coring using NMLC technique. To protect the hole from
collapse during rock coring using drilling water in boreholes BH3 and BH4, casings were
therefore installed to the bottom of augered holes.
The borehole locations are shown in Appendix A. Engineering logs of boreholes processed
using Bentley gINT software together with borehole explanatory notes are presented in
Appendix C. The rock core photographs are attached in Appendix D of this report.
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4.3 Point Load Strength Index (PLSI) Test
Point Load Strength Index (PLSI) Tests are used to obtain the estimates of rock strength
and may be related to Unconfined Compressive Strength (UCS) by an appropriate
correlation. The tests were conducted in both axial and diametrical directions.
A total of six (6) core samples were selected for PLSI tests. The test results are shown on
borehole logs and provided in Appendix E of this report.
4.4 Laboratory Test
Soil samples was also taken within a depth between 2.0m and 3.0m BGL in borehole BH3
during drilling. The soil samples were sent to a NATA accredited laboratory for
undertaking the following tests:
Electrical Conductivity (Salinity);
Aggressivity test (pH, Sulfate and Chloride); and
Exposure classification.
The results of laboratory test are attached in Appendix F of this report.
5. RESULTS OF INVESTIGATION
5.1 Surface Conditions
During site investigation, apart from existing building, a concrete tank, a gravel driveway
and an overhead transmission line easement, the remainder of the site was covered with
grass and shrubs. A number of young and mature trees were present within the site.
5.2 Subsurface Conditions
The subsurface conditions encountered in boreholes BH1 to BH4 are shown on the
Engineering Borehole Logs in Appendix C. Based on borehole information, the subsurface
conditions encountered at testing locations consisted of the following:
Residual Soils (Unit 1): Silty CLAY, low to medium plasticity, brown and red
mottled brown, dry to moist, stiff to very stiff, with a 0.2m - 0.3m thick topsoil,
extending approximately to 2.3m, 1.6m, 1.5m and 3.0m BGL; overlying
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Class V Shale (Unit 2): brown, extremely weathered, extremely low and low
strength, extending to TC-bit refusal at approximate depth of approximately 4.6m,
5.0m, 3.0m and 6.1m BGL in boreholes BH1 and BH4 inclusive; overlying
Class IV Shale (Unit 3): light grey, moderately weathered, medium strength,
extending approximately to between 3.4m and 7.0m BGL at boreholes BH3 and
BH4 respectively; overlying
Class III Siltstone and Shale (Unit 4): light grey, slightly weathered, medium to
high strength, based on results of laboratory test and rock cores recovered from
boreholes BH3 & BH4.
Classification of the rock was carried out in accordance with the guidelines provided by
Pells et al (Reference 7).
The subsurface conditions encountered in boreholes BH1 to BH4 during site investigation
are summarised in Table 1 below.
Table 1 - Summary of Subsurface Conditions
Geotechnical Unit and Description Depth and RL at Top of Unit
BH1 BH2 BH3 BH4
ID Unit Description Depth
(m, BGL)
RL
(m, AHD)
Depth
(m, BGL)
RL
(m, AHD)
Depth
(m, BGL)
RL
(m, AHD)
Depth
(m, BGL)
RL
(m, AHD)
Unit 1
Residual Soils: silty
CLAY, stiff to very
stiff
0 62.2 0 63.1 0 69.1 0 66.7
Unit 2 Class V SHALE, EW,
EL- L 2.3 59.9 1.6 61.5 1.5 67.6 3.0 63.7
Unit 3 Class IV SHALE, MW,
M 4.6 57.6 5.0 58.1 3.0 66.1 6.1 60.6
Unit 4 Class III SILTSTONE
& SHALE, SW, M-H Unconfirmed Unconfirmed 3.4 65.7 7.0 59.7
Notes: RL – Reduced Level; EW – Extremely weathered; MW – Moderately weathered; SW – Slightly weathered; EL – Extremely low strength; L – Low strength; M – Medium strength, H – High strength.
5.3 Groundwater
(a) General
Based on Fact Sheet 1: Groundwater and the Sydney Coastal Region (Reference 10),
groundwater is the water contained within rocks and sediments below the ground surface in
the saturated zone. Groundwater sources are divided into four broad hydrogeological types:
Alluvium: unconsolidated sediments
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Coastal sand: unconsolidated sediments, such as Botany sand.
Porous rock: Hawkesbury Sandstone Formation and Narrabeen Group sandstone
Fractured rock: Wianamatta Group shale: Ashfield Shale & Bringelly Shale.
We assessed that the groundwater within the site is likely to be phreatic water sourced from
fractured rock in Bringelly Shale, which relies on the conditions and interconnectivity of
fractures/defects within rock formation.
(b) Groundwater conditions
No groundwater was encountered in boreholes during drilling using augering technique up
to 4.6m, 5.0m, 3.0m and 6.1m BGL respectively in borehole BH1 and BH4 inclusive,
where dry drilled material was recovered from bottom of holes prior to rock coring.
Measurement of seepage or water levels during core drilling below depths achieved by
augering was not possible due to the introduction of water required for rock coring.
It is inferred that natural groundwater level or phreatic surface may be deeper at this site
and likely present within fractures/defects in the rock, including apertures, joints or other
natural defects within the underlying siltstone and shale.
During basement excavation, minor seepage or water inflow may occur within interface of
soils and rocks and fractures/defects of rock if it encounters an intense and prolonged
rainfall event.
5.4 Laboratory Test
During the investigation, the soil samples were obtained from borehole BH3. The samples
were tested for determination of salinity and aggressivity parameters by a NATA
accredited laboratory. The laboratory test report is attached in Appendix F and results of
test are summarised in Table 2 overleaf.
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Table 2: Results of Laboratory Test on Soil Samples
Borehole BH3 (GW1) pH Chloride
(mg/kg)
Sulphate as SO4
(mg/kg)
Electrical
Conductivity
EC* (dS/m)
BH3-1 4.9 540 110 0.46
Exposure Classification1 Mildly aggressive -
Salinity - No-saline2
Note: 1 – “Soil condition B – low permeability soils (e.g. silts and clays) or all soils above groundwater”
adopted for this site in accordance with AS2159-2009 Piling - Design and Installation; 2 - Classification of soil salinity based on Environmental Planning & Assessment Regulation 1994 &
Dryland Salinity: Productive Use of Saline Land and Water as below:
Class Salinity Class ECe* (dS/m) Comments
No-saline 0 <2 Possible waterlogging
Slightly saline 1 2 – 4 Some salt tolerant species (e.g. sea barley
grass) but no bare patches
Moderately saline 2 4 – 8 Small bare patches
Very saline 3 8 – 16 Large bare areas
Highly saline 4 >16
*ECe calculated from EC by applying a multiplication factor between 7 to 17.
6. GEOTECHNICAL ASSESSMENTS
The main geotechnical aspects associated with the proposed development are assessed to
include the following:
Site classifications;
Excavation conditions;
Stability of basement excavation and shoring/support;
Earth retaining structures;
Foundations;
Earthworks and material reuse;
Salinity assessment;
Groundwater management; and
Preliminary comments on pavement design.
The assessment of the geotechnical aspects on the above and recommendations for the
proposed development are presented in the following sections.
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6.1 Site Characterisation and Classifications
(a) Site characterisation
In accordance with AS2159-2009 (Reference 3), the results of soil aggressivity test
presented in Table 2 indicate that the exposure classifications of tested soil samples may be
classified as “Mildly-aggressive” to concrete and steel elements.
(b) Site reactivity classification
Based on the site soil profile, proposed development and the criteria specified in AS2870 –
2011 (Reference 2), the site can be assessed as Class M – Moderately reactive clay or silt
sites, which may experience moderate ground movement from moisture changes. However,
during basement excavation, residual soils (Unit 1) and Class V Shale (Unit 2) will be
excavated and the footing systems at basement floor level will be founded predominately
within Class IV or better rock and protected from becoming extremely wet. Therefore, it
can be classified as Class A or Class S and may be treated as “non-reactive” site for the
proposed development.
(c) Site earthquake classification
The results of the site investigation indicate the presence of residual cohesive soils,
underlain by Class V Shale or better rock. In accordance with Australian Standard
AS1170.4-2007(Reference 5), the site sub-soil may be classified as a “Rock Site” (Class
Be) for design of foundations and retaining walls. The Hazard Factor (Z) for Rouse Hill in
accordance with AS1170.4 is considered to be 0.08.
6.2 Excavation Conditions
It is anticipated that construction excavation will include excavation of basement, driveway
ramp, proposed roads, footing areas and lift shafts, and trenches for underground pipelines.
Based on information provided in Section 1.1, excavation depths within proposed basement
area are expected to vary between 3.0m and 7.0m BGL approximately within footprints of
proposed basement and/or lower ground levels. The results of the geotechnical site
investigation indicate basement excavation for proposed buildings will likely be within
Residual Soils (Unit 1), Class V Shale (Unit 2), Class IV Shale (Unit 3) and minor Class III
Siltstone & Shale (Unit 4). Medium and high strength siltstone and shale is likely to be
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encountered during excavation of basement level in vicinity of borehole BH3, which is
located within middle portion of the site.
Excavation of residual soils and Class V Shale will be typically feasible using conventional
earthmoving equipment. Excavation of low strength Class IV Shale may be feasible with
conventional earthmoving equipment and ripping equipment. Medium strength and less
fractured Class IV Shale & medium to high strength Class III Siltstone & Shale would
require heavy ripping and rock breaking equipment or vibratory rock breaking equipment.
6.3 Excavation Support / Stability of Basement Excavation
(a) Shallow Excavation (i.e. <1.5 m in Depth)
The excavations should be benched in accordance with the „NSW WorkCover: Code of
Practice – Excavation‟ March 2000.
Temporary excavations through the underlying residual soils to a maximum depth of 1.5m,
may be excavated near vertical provided that:
They are barricaded when not in use;
They are not left open for more than 24 hours;
No surcharge loading is applied within 1.5m of the edge of the excavation;
No groundwater flows are encountered; and
They are not used for access by a worker.
Where access is required for workers, the temporary excavation batters should be re-graded
to no steeper than 2 Horizontal (H) to 1 Vertical (V) for the fill above the natural
groundwater level, or supported by suitable temporary shoring measures. Any permanent
excavation (or filling) greater than 0.5m in height should be retained by a permanent
retaining wall to be designed based on the recommendation provided in Section 6.4 of this
report.
(b) Deep Excavations (i.e. >1.5 m in Depth)
If required, any excavation batters in soils and/or rocks greater than 1.5 m in depth, the
temporary safe batters for excavated slopes in Table 3 overleaf can be adopted under dry
conditions:
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Table 3: Recommended Safe Excavation Batters1
Geotechnical Unit3
Maximum Batter Angle
Temporary Permanent
Residual Soils (Unit 1) 1.5H:1V 2H:1V
Class V Shale (Unit 2) 1H:2.5V to Sub-vertical
2
with shotcrete2
1H:2.5V to Sub-vertical2
with rock bolts combined with reinforced shotcrete
Class IV Shale (Unit 3) Vertical with shotcrete Vertical with shotcrete2
Class III Siltstone & Shale (Unit 4) Vertical, self-supporting Vertical, self-supporting2
Notes: 1 - Typical temporary batters of excavated slopes (Hoerner, 1990). Assume no surcharge on top of
cutting batter and no major adjoining structures. Excavation using benching technique can be adopted. 2 – Reinforced shotcrete and/or rock bolts may be required for vertical or sub-vertical cut slope in this
unit subject to assessment by an experienced Geotechnical Engineer during excavation. 3 – Approximate RLs at top of unit and rock classification refers to Table 1.
Based on proposed setbacks and approximate excavation depths provided in Section 1.2,
we assessed basement excavation using safe batters recommended in Table 3 would be
feasible for the proposed development.
However, due to some reasons, if excavation using batter slopes are not practical or
possible, other options to shore and support the excavation and control lateral ground
movement may be considered subject to assessment by the project Structural Engineer in
consultation with the project Geotechnical Engineer include the following:
Soil nail wall system; or
Soldier pile wall shoring system.
Earth retention structures can be designed using the recommended parameters provided in
Section 6.4.
During basement excavation, observations and recording on conditions of exposed faces
should be carried out by the project Geotechnical Engineer, so that loose materials or weak
rock within the excavated rock face can be identified and treated as appropriate.
Inspections of the excavation faces/shoring measures by a Geotechnical Engineer during
construction will be required.
6.4 Earth Retaining Structures
If an earth retaining structure is adopted, it should be designed to withstand the applied
lateral pressures of the subsurface layers, the surcharges in their zone of influence,
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including loading from existing structures, construction machinery, traffic and construction
related activities. The design of retaining structures should also take into consideration
hydrostatic pressures and lateral earthquake loads as appropriate.
The recommended preliminary parameters for the design of retaining structures are
presented in Tables 4 and 5 below. The coefficients provided are based on drained
conditions.
Table 4: Preliminary Geotechnical Design Parameters for Retaining Walls
Geotechnical Unit
Unit
Weight
(kN/m3)
Effective
Cohesion
c (kPa)
Angle of
Effective
Internal Friction
(degree)
Modulus of
Elasticity
Es (h) (MPa)
Poisson’s
Ratio ()
Residual Soils (Unit 1) 18 5 27 20 0.35
Class V Shale (Unit 2) 22 40 28 100 0.35
Class IV Shale (Unit 3) 24 80 28 250 0.30
Class III Siltstone & Shale
(Unit 4) 24 150 32 400 0.20
Table 5: Preliminary Coefficients of Lateral Earth Pressure
Geotechnical Unit
Coefficient of
Active Lateral
Earth Pressure
(Ka)
Coefficient of
Lateral Earth
Pressure at Rest
(Ko)
Coefficient of
Passive Lateral
Earth Pressure
(Kp)
Residual Soils (Unit 1) 0.38 0.55 2.7
Class V Shale (Unit 2) 0.36 0.53 2.8
Class IV Shale (Unit 3) 0.36 0.53 2.8
Class III Siltstone & Shale (Unit 4) 0.31 0.47 3.3
The coefficients of lateral earth pressure should be verified by the project Structural
Engineer prior to use in the design of retaining walls. Simplified calculations of lateral
active (or at rest) and passive earth pressures can be carried out using Rankine‟s equation
shown below:
√ For calculation of Lateral Active or At Rest Earth Pressure
√ For calculation of Passive Earth Pressure
Where:
Pa = Active (or at rest) Earth Pressure (kN/m2)
Pp = Passive Earth Pressure (kN/m2)
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No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
= Bulk density (kN/m3)
K = Coefficient of Earth Pressure (Ka or Ko)
Kp = Coefficient of Passive Earth Pressure
H = Retained height (m)
c = Effective Cohesion (kN/m2)
For design of soils nails or temporary ground anchors, the allowable bond stress of 20kPa,
40kPa, 120kPa and 200kPa can be adopted within Residual Soils (Unit 1), Class V Shale
(Unit 2), Class IV Shale (Unit 3), and Class III Shale (Unit 4) respectively. The following
is recommended for the anchor design:
Anchor bond length of at least 3m behind the “active” zone of the excavation;
Overall stability of anchor system and interaction is satisfactory; and
The anchors are proof loaded to at least 1.3 times the design working load before
locking off at working load.
6.5 Foundations
Based on proposed elevation of basement and ground profile encountered in the boreholes,
basement floor slabs are likely to be founded predominantly in Class IV Shale (Unit 3) or
better rock.
We assessed that a foundation system consisting of cast-in-situ reinforced concrete shallow
foundations, such as pad or strip footings under columns and walls, would be applicable for
the proposed development at this site.
Installation of piles is expected to be required in case of large axial loads on columns and
walls and exceeding the bearing pressure of the bearing stratum. Other cases where piles
may be required include the need to increase the stiffness of the founding rock, or increase
the resistance against lateral seismic loads. Piles are expected to be socketed into
underlying Class III Siltstone & Shale or better rock. Bored piles would be applicable for
this site.
Preliminary geotechnical capacities and parameters recommended for design of shallow
and piled foundations are provided in Table 6 overleaf.
Page 19 of 23
No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
Table 6: Preliminary Geotechnical Foundation Design Capacities and Parameters
Geotechnical Unit Allowable End Bearing
Pressure (kPa1)
Allowable Shaft
Adhesion
Compression2 (kPa)
Modulus of
Elasticity,
Es,v (MPa)
Residual Soils (Unit 1) 150 (Shallow footing) 40 20
Class V Shale (Unit 2) 500 (shallow footing)
700 (piles) 50 150
Class IV Shale (Unit 3) 1000 (shallow footing)
1500 (piles) 150 300
Class III Siltstone & Shale
(Unit 4)
3000 (shallow footing)
3500 (piles) 300 500
1 With a minimum embedment depth of 0.5m for piled foundations and 0.3m for shallow foundations. 2 Shaft Adhesion applicable to piles only. 3 N/A, Not Applicable or not recommended for the proposed development. 4 The actual depth of underlying Class V Shale to Class III Shale should be confirmed during construction.
Design of shallow and pile foundations should be carried out in accordance with Australian
Standards AS2870-2011 (Reference 2) and AS2159-2009 (Reference 3) respectively.
To minimise the potential effects of differential settlement under the buildings loads, it is
recommended all foundations of the proposed building should be founded on consistent
materials of similar properties or rock of similar class.
Excavations of shallow foundation may need to be dewatered if seepages or surface runoff
are present within excavated pits/trenches, in particular when intense and prolonged
rainfall occurs. Any loose debris and wet material should be removed from excavations.
An experienced Geotechnical Engineer should be engaged to inspect footing excavations
and construction to ensure foundation bases have suitable materials with adequate bearing
capacity, and to check the adequacy of footing embedment depth or pile socket length.
Verification of embedment depth/socket length, founding material and bearing capacity of
foundation material by inspections would be required and inspections should constitute as
“Hold Points”.
6.6 Salinity Assessment
Based on results of laboratory tests, the electrical conductivity (EC) of water sample may
be classified as “No-saline” in accordance with Dryland Salinity (1993).
In accordance with Western Sydney Salinity Code of Practice (Reference 11), a site which
is located within an area of “No-saline” may seem to have negligible or very low potential
to create a salinity problem on the site.
Page 20 of 23
No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
6.7 Groundwater Management
The observations summarised in Section 5.3(b) indicate no groundwater during drilling up
to a depth of 6.1m BGL. We assessed that during basement excavation the potential to
occur large amount of inflow/seepage through soils, interface of soils and rocks, and
through joints within siltstone/shale is very minor.
Nevertheless, it would be prudent at this stage of the design to allow for precautionary
drainage measures in the design and construction of the proposed development. Such
measures would include the following:
Strip drains or drainage materials should be installed behind the shoring/retaining
walls.
Collection trenches or pipes and pits connected to the building stormwater system.
A stormwater storage tank and pump system may be required.
The basement walls and floor maybe designed and constructed with water-tight
construction joints.
The basement walls and slabs should be designed to withstand hydrostatic pressures
taking into consideration the potential for seepage.
Seepage or subsurface runoff inside the excavated foundation pits or pile holes
should be removed prior to pouring of concrete.
During intense and prolonged rainfall period, basement excavations would typically require
a temporary sump pit within the site to collect and remove any surface water or seepage
that may occur.
With the recommended procedures and precautionary mitigation measures described
above, the potential impacts of the proposed development on surrounding properties and
road are expected to be negligible.
6.8 Earthworks and Material Reuse
Based on the information provided on the proposed development, it is anticipated that
earthworks may involve the following:
Excavation within basement areas and driveway ramps;
Excavation within structural footings areas and lift shafts;
Cut/fill for proposed roads;
Page 21 of 23
No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
Excavation and backfilling during installation of underground pipes; and
Subgrade preparation for footpath and pavement areas.
The excavated materials from excavation are assessed to be generally suitable for
landscaping provided they are free of any contaminants.
The suitability of the excavated materials for engineering fill should be subject to satisfying
the following criteria:
The materials should be clean (i.e. free of contaminants, deleterious or organic
material), free of inclusions of >75mm in size, high plasticity material be removed
and suitably conditioned to meet the design assumptions where fill material is
proposed to be used.
The materials should satisfy the Australian Standard AS 3798-2007 Guidelines on
Earthworks for Commercial and Residential Developments (Reference 4).
The final surface levels of all excavation and filling areas should be compacted in order to
achieve an adequate strength for subgrade.
For the fill construction, the recommended compaction targets should be the following:
Moisture content of ±2% of OMC (Optimal Moisture Content);
Minimum density ratio of 100% of MDD (Maximum Dry Density) for filling
within building/structural foundation areas;
Minimum density ratio of 98% of MDD for backfilling surrounding the pipes
within trenches;
The loose thickness of layer should not exceed 150mm for cohesive soils and
250mm for cohesionless soils; and
For the footpath and pavement areas, minimum density ratio of 95% of MDD for
general fill and 98% for the subgrade to 0.5m depth.
Design and construction of earthworks should be carried out in accordance with Australian
Standard AS 3798-2007 (Reference 4).
6.9 Preliminary Comments on Pavement Subgrade
It is recommended that pavement can be designed on a CBR value of 5% on stiff residual
soils or medium dense granular subgrade.
Page 22 of 23
No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
Any loose or soft materials that may be present during construction, as confirmed by a site
inspection and in-situ testing, should be either removed or improved by compaction in
order to increase the strength of the material. The final levels of subgrade should be
tested/proof rolled and inspected by an experienced Geotechnical Engineer.
Pavement design should be carried out in accordance with “Pavement Design – A Guide to
the Structural Design of Road Pavements” (Reference 8) and should be complemented by
the provision of adequate surface and subsurface drainage.
7. CONCLUSIONS AND RECOMMENDATIONS
The results of the geotechnical investigation and assessment for this site indicate the
ground conditions are suitable for the proposed development. A foundation system
consisting of cast-in-situ reinforced concrete shallow foundations, such as pad or strip
footings, would be applicable for the proposed development at this site. Piles are expected
to be required in case of large axial loads on columns and walls and exceeding the bearing
pressure of the bearing stratum or other cases as discussed in Section 6.5. Bored piles
would be suitable for this site.
Based on results of laboratory tests, the site may be classified as “No-saline” and “Mildly
aggressive” to concrete and steel elements in terms of exposure classification.
The construction excavation, excavation safe batters/shoring/support, and drainage works
should be implemented in accordance with the recommendations provided in Sections 6.2,
6.3, 6.4 and 6.7 of this report.
It is recommended that an experienced Geotechnical Engineer should be engaged to inspect
foundation excavations to ensure the foundation base have been taken to suitable materials
of appropriate bearing capacity and adequate embedment depth/socket length.
We assessed that the proposed development will have negligible impacts arising from
salinity issue.
It is recommended the final civil and structural design drawings for the proposed
development should be provided to us for further assessment and confirmation of suitable
mitigation measures, foundation system, bearing capacity of founding material and
embedment depth, retaining walls and drainage systems.
Page 23 of 23
No. 105 Cudgegong Road, Rouse Hill, NSW 2155 Ref No.: ESWN-PR-2017-118
Geotechnical Investigation Report 26th June 2017
8. LIMITATIONS
This report should be read in conjunction with the “Limitations of Geotechnical
Investigation Statement” attached as Appendix G, which provides important information
regarding geotechnical investigation, assessment and reporting. If the actual subsurface
conditions exposed during construction vary significantly from those discussed in this
report, this report should be reviewed and further consultation and advices from
ESWNMAN are necessary.
For and on behalf of
ESWNMAN Pty Ltd
Jiameng Li
BE (Civil), MEngSc (Geotechnical), MIEAust, CPEng, NER Principal Geotechnical Engineer
ESWNMAN PTY LTD PO Box 6, Ashfield NSW 1800 M: +61 421 678 797 E: [email protected] http://www.eswnman.com.au
© ESWNMAN Pty Ltd
APPENDIX A
___________________________________
SITE LOCATION PLAN
PROJECT: 105 Cudgegong Road, Rouse Hill, NSW DRAWN BY: J.L.
CLIENT: Weyand Pty Ltd
PROJECT NO: ESWN-PR-2017-118 DATE: 26th June 2017
TITLE:
Site Location Plan Figure 1
SITE BOUNDARY
No. 7-9
N
No. 1
No. 32
No. 2-4
No. 6
Lot 81 in DP 208203
BH1
BH2
No. 105
Cudgegong Road
No. 3
No. 5
No. 36
No. 18
No. 8
BH1(GW1)
LEGEND Approximate Location of Borehole (BH) Image Source: Architectural drawings titled “Residential Development, 105 Cudgegong Road, Rouse Hill” prepared by Dreamscapes Architects, referenced Project No. 17003, drawing no. A101,and dated 6th June 2017
No. 95
Cudgegong Road
BH3
Proposed Development
BH4
BH2
_________________________________________________________________________ © ESWNMAN Pty Ltd
APPENDIX B
___________________________________
SITE PHOTOGRAPHS
26th
June 2017
Ref: ESWN-PR-2017-118 No.105 Cudgegong Road, Rouse Hill, NSW 2155
Geotechnical Investigation
____________________________________________________________________________________________________________________________________________________________________________
© ESWNMAN PTY LTD
Photograph 1 Front entry to No. 105 Cudgegong Road facing southwest
Photograph 2 Drilling at location of borehole BH1
Photograph 3 No indication of groundwater from drilling spoils
when augering to 4.6m depth
Photograph 4 View of existing building facing northwest
Photograph 5 Drilling at location of borehole BH3 (rock coring)
Photograph 6 Drilling at location of borehole BH4 showing no indication of
groundwater up to 6.1m depth
Appendix B Site Photographs
© ESWNMAN Pty Ltd
APPENDIX C
___________________________________
ENGINEERING BOREHOLE LOGS
AND EXPLANATORY NOTES
AS
T
NO
T E
NC
OU
NT
ER
ED
SPT6, 40/120mm
RESIDAUL SOILS
SHALE
TC refusal at 4.6m depth
CL Silty CLAY, medium plasticity, red mottled brown, moist, stiff to very stiff. Topsoil at0-0.2m depth.
SHALE, grey, extremely weathered, extremely low strength.
Borehole BH1 terminated at 4.6m
Met
hod
Wat
er
SamplesTests
RemarksAdditional Observations
BOREHOLE NUMBER BH1PAGE 1 OF 1
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 62.2 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
BO
RE
HO
LE /
TE
ST
PIT
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
RL(m)
62
61
60
59
58
57
56
55
54
53
Depth(m)
1
2
3
4
5
6
7
8
9
10
Cla
ssifi
catio
nS
ymbo
l Material Description
Gra
phic
Log
AS
T
NO
T E
NC
OU
NT
ER
ED
SPT7, 15, 22/100mm
RESIDAUL SOILS
SHALE
TC refusal at 5.0m depth
CL Silty CLAY, low plasticity, brown, dry to moist, trace gravel, stiff to very stiff. Topsoil at0-0.15m depth.
SHALE, grey, extremely weathered, extremely low to low strength.
Borehole BH2 terminated at 5m
Met
hod
Wat
er
SamplesTests
RemarksAdditional Observations
BOREHOLE NUMBER BH2PAGE 1 OF 1
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 63.1 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
BO
RE
HO
LE /
TE
ST
PIT
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
RL(m)
63
62
61
60
59
58
57
56
55
54
Depth(m)
1
2
3
4
5
6
7
8
9
10
Cla
ssifi
catio
nS
ymbo
l Material Description
Gra
phic
Log
AS
T
NO
T E
NC
OU
NT
ER
ED
SPT4, 18, 13/40mm
RESIDAUL SOILS
SHALE
TC refusal at 3.0m depth
CL Silty CLAY, low plasticity, brown, dry, trace shale gravel, stiff to very stiff.
SHALE, grey, extremely weathered, extremely low to low strength.
- Casing installed to 3.0m depth during NMLC coring.Borehole BH3 continued as cored hole
Met
hod
Wat
er
SamplesTests
RemarksAdditional Observations
BOREHOLE NUMBER BH3PAGE 1 OF 2
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 69.1 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
BO
RE
HO
LE /
TE
ST
PIT
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
RL(m)
69
68
67
66
65
64
63
62
61
60
Depth(m)
1
2
3
4
5
6
7
8
9
10
Cla
ssifi
catio
nS
ymbo
l Material Description
Gra
phic
Log
HW
MWSW
NO
T E
NC
OU
NT
ER
ED
- CORE LOSS
- DB
- DB- J, P, S, 0°- B, P, S, 0°
- B, P, S, 0°- J, Ir, R, 15-20°
- J, P, S, 0°
- J, P, S, 10°- J, P, R, 5°
- J, Ir, R, 5°- J, P, S, 0°, iron stain
- J, P, R, 0-5°
- DB- J, Ir, R, 0-5°
- J,P, R, 5°, iron stain
- 2xJ, P, S, 0°
NM
LC
A1.61
A0.85
A1.48
D3.41
D1
D1.52
088
CORE LOSS
SILTSTONE, light grey
SHALE, grey.
SILTSTONE, light grey
SHALE, greySILTSTONE, light grey
SHALE, grey
Continued from non-cored borehole
BH3 terminated at 7m
Wea
ther
ing
diam-etralaxial
30 100
300
1000
3000
EstimatedStrength
EstimatedStrength
Wat
er
EL
VL
L M H VH
EH
Defect Description
DefectSpacing
mm
A-
D-
Met
hod
Is(50)
MPa
RQ
D %
BOREHOLE NUMBER BH3PAGE 2 OF 2
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 69.1 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
CO
RE
D B
OR
EH
OLE
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
Material Description
RL(m)
69
68
67
66
65
64
63
62
61
60
Depth(m)
1
2
3
4
5
6
7
8
9
10
Gra
phic
Log
AS
T
NO
T E
NC
OU
NT
ER
ED
RESIDAUL SOILS
SHALE
TC refusal at 6.1m depth
CL Silty CLAY, low plasticity, brown, dry to moist, trace gravel, stiff to very stiff. Topsoil at0-0.3m depth.
SHALE, grey, extremely weathered, extremely low to low strength.
- sandstone band at 3.3m depth
- Casing installed to 6.0m depth during NMLC coring.Borehole BH4 continued as cored hole
Met
hod
Wat
er
SamplesTests
RemarksAdditional Observations
BOREHOLE NUMBER BH4PAGE 1 OF 2
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 66.7 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
BO
RE
HO
LE /
TE
ST
PIT
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
RL(m)
66
65
64
63
62
61
60
59
58
57
Depth(m)
1
2
3
4
5
6
7
8
9
10
Cla
ssifi
catio
nS
ymbo
l Material Description
Gra
phic
Log
HW
MW
SW
NO
T E
NC
OU
NT
ER
ED
- CORE LOSS
- J, Ir, R, 5-10°- DB
- B, P, S, 0°- 2xJ, P, S, 0°- J, P, S, 15-20°
- B, P, S, 0°
- J, P, S, 0-5°
- 2xB, P, S, 0°
- B, P, S, 0°- J, P, R, 0°- B, P, S, 0°- B, P, S, 0°
- DB
NM
LC
A0.55
A1.51
A0.78
D0.08
D1.53
D0.66
075
CORE LOSS
SILTSTONE, light grey - shale band at 6.5m-6.6m
- shale band at 6.82m - shale bands at 6.94-6.96m
SHALE, grey
Continued from non-cored borehole
BH4 terminated at 9m
Wea
ther
ing
diam-etralaxial
30 100
300
1000
3000
EstimatedStrength
EstimatedStrength
Wat
er
EL
VL
L M H VH
EH
Defect Description
DefectSpacing
mm
A-
D-
Met
hod
Is(50)
MPa
RQ
D %
BOREHOLE NUMBER BH4PAGE 2 OF 2
COMPLETED 29/5/17DATE STARTED 29/5/17
DRILLING CONTRACTOR BG Drilling Pty Ltd
LOGGED BY J.L. CHECKED BY J.L.
NOTES RL top of borehole is approximate
HOLE LOCATION Refer to Figure 1EQUIPMENT Han-Jin 8D
HOLE SIZE 110mm Diameter
R.L. SURFACE 66.7 DATUM m AHD
SLOPE 90° BEARING ---
CLIENT Weyand Pty Ltd
PROJECT NUMBER ESWN-PR-2017-118
PROJECT NAME Geotechnical Investigation
PROJECT LOCATION 105 Cudgegong Road, Rouse Hill, NSW
CO
RE
D B
OR
EH
OLE
ES
WN
-PR
-201
7-11
8.G
PJ
GIN
T S
TD
AU
ST
RA
LIA
.GD
T 6
/6/1
7ESWNMAN PTY LTDPO Box 6Ashfield NSW 1800Telephone: 0279015582
Material Description
RL(m)
66
65
64
63
62
61
60
59
58
57
Depth(m)
1
2
3
4
5
6
7
8
9
10
Gra
phic
Log
© ESWNMAN Pty Ltd 1
Explanatory Notes – Description for Soil In engineering terms soil includes every type of uncemented or partially cemented inorganic material found in the ground. In practice, if the material can be remoulded by
hand in its field condition or in water it is described as a soil. The dominant soil constituent is given in capital letters, with secondary textures in lower case. The dominant
feature is assessed from the Unified Soil Classification system and a soil symbol is used to define a soil layer .
METHOD
Method Description
AS Auger Screwing
BH Backhoe
CT Cable Tool Rig
EE Existing Excavation/Cutting
EX Excavator
HA Hand Auger
HQ Diamond Core-63mm
JET Jetting
NMLC Diamond Core –52mm
NQ Diamond Core –47mm
PT Push Tube
RAB Rotary Air Blast
RB Rotary Blade
RT Rotary Tricone Bit
TC Auger TC Bit
V Auger V Bit
WB Washbore
DT Diatube
WATER
Water level at date shown Partial water loss
Water inflow Complete water loss
NFGWO: The observation of groundwater, whether present or not, was not possible
due to drilling water, surface seepage or cave in of the borehole/test pit.
NFGWE: The borehole/test pit was dry soon after excavation. Inflow may have
been observed had the borehole/test pit been left open for a longer period.
SAMPLING
Sample Description
B Bulk Disturbed Sample
D Disturbed Sample
Jar Jar Sample
SPT Standard Penetration Test
U50 Undisturbed Sample –50mm
U75 Undisturbed Sample –75mm
UNIFIED SOIL CLASSIFICATION
The appropriate symbols are selected on the result of visual examination, field tests
and available laboratory tests, such as, sieve analysis, liquid limit and plasticity
index.
USC Symbol Description
GW Well graded gravel
GP Poorly graded gravel
GM Silty gravel
GC Clayey gravel
SW Well graded sand
SP Poorly graded sand
SM Silty sand
SC Clayey sand
ML Silt of low plasticity
CL Clay of low plasticity
OL Organic soil of low plasticity
MH Silt of high plasticity
CH Clay of high plasticity
OH Organic soil of high plasticity
Pt Peaty Soil
MOISTURE CONDITION
Dry - Cohesive soils are friable or powdery
Cohesionless soil grains are free-running
Moist - Soil feels cool, darkened in colour
Cohesive soils can be moulded
Cohesionless soil grains tend to adhere
Wet - Cohesive soils usually weakened
Free water forms on hands when handling
For cohesive soils the following codes may also be used:
MC>PL Moisture Content greater than the Plastic Limit.
MC~PL Moisture Content near the Plastic Limit.
MC<PL Moisture Content less than the Plastic Limit.
PLASTICITY
The potential for soil to undergo change in volume with moisture change is assessed
from its degree of plasticity. The classification of the degree of plasticity in terms of
the Liquid Limit (LL) is as follows:
Description of Plasticity LL (%)
Low <35
Medium 35 to 50
High >50
COHESIVE SOILS - CONSISTENCY
The consistency of a cohesive soil is defined by descriptive terminology such as very
soft, soft, firm, stiff, very stiff and hard. These terms are assessed by the shear
strength of the soil as observed visually, by hand penetrometer values and by
resistance to deformation to hand moulding.
A Hand Penetrometer may be used in the field or the laboratory to provide an
approximate assessment of the unconfined compressive strength (UCS) of cohesive
soils. The undrained shear strength of cohesive soils is approximately half the UCS.
The values are recorded in kPa as follows:
Strength Symbol Undrained Shear Strength, Cu (kPa)
Very Soft VS < 12
Soft S 12 to 25
Firm F 25 to 50
Stiff St 50 to 100
Very Stiff VSt 100 to 200
Hard H > 200
COHESIONLESS SOILS - RELATIVE DENSITY
Relative density terms such as very loose, loose, medium, dense and very dense are
used to describe silty and sandy material, and these are usually based on resistance to
drilling penetration or the Standard Penetration Test (SPT) „N‟ values. Other
condition terms, such as friable, powdery or crumbly may also be used.
Term Symbol Density Index N Value
(blows/0.3 m)
Very Loose VL 0 to 15 0 to 4
Loose L 15 to 35 4 to 10
Medium Dense MD 35 to 65 10 to 30
Dense D 65 to 85 30 to 50
Very Dense VD >85 >50
COHESIONLESS SOILS PARTICLE SIZE DESCRIPTIVE TERMS
Name Subdivision Size
Boulders
Cobbles
>200 mm
63 mm to 200 mm
Gravel coarse
medium
fine
20 mm to 63 mm
6 mm to 20 mm
2.36 mm to 6 mm
Sand coarse
medium
fine
600 m to 2.36 mm
200 m to 600 m
75 m to 200 m
© ESWNMAN Pty Ltd 2
Description for Rock The rock is described with strength and weathering symbols as shown below. Other features such as bedding and dip angle are given.
METHOD
Refer soil description sheet
WATER
Refer soil description sheet
ROCK QUALITY
The fracture spacing is shown where applicable and the Rock Quality Designation
(RQD) or Total Core Recovery (TCR) is given where:
TCR (%) = length of core recovered
length of core run
RQD (%) = Sum of Axial lengths of core > 100mm long
length of core run
ROCK MATERIAL WEATHERING
Rock weathering is described using the abbreviations and definitions used in
AS1726. AS1726 suggests the term “Distinctly Weathered” (DW) to cover the
range of substance weathering conditions between (but not including) XW and SW.
For projects where it is not practical to delineate between HW and MW or it is
deemed that there is no advantage in making such a distinction, DW may be used
with the definition given in AS1726.
Symbol Term Definition
RS Residual Soil Soil definition on extremely weathered rock;
the mass structure and substance are no
longer evident; there is a large change in
volume but the soil has not been
significantly transported
XW Extremely
Weathered
Rock is weathered to such an extent that it
has „soil‟ properties, ie. It either
disintegrates or can be remoulded in water
HW
DW
Highly
Weathered
Distinctly
Weathered (see
AS1726
Definition
below)
The rock substance is affected by
weathering to the extent that limonite
staining or bleaching affects the whole rock
substance and other signs of chemical or
physical decomposition are evident.
Porosity and strength is usually decreased
compared to the fresh rock. The colour and
strength of the fresh rock is no longer
recognisable.
MW Moderately
Weathered
The whole of the rock substance is
discoloured, usually by iron staining or
bleaching, to the extent that the colour of the
fresh rock is no longer recognisable
SW Slightly
Weathered
Rock is slightly discoloured but shows little
or no change of strength from fresh rock
FR Fresh Rock shows no sign of decomposition or
staining
“Distinctly Weathered: Rock strength usually changed by weathering. The rock
may be highly discoloured, usually by iron staining. Porosity may be increased by
leaching, or may be decreased due to the deposition of weathering products in
pores.” (AS1726)
ROCK STRENGTH
Rock strength is described using AS1726 and ISRM - Commission on
Standardisation of Laboratory and Field Tests, "Suggested method of determining
the Uniaxial Compressive Strength of Rock materials and the Point Load Index", as
follows:
Term Symbol Point Load Index
Is(50) (MPa)
Extremely Low EL <0.03
Very Low VL 0.03 to 0.1
Low L 0.1 to 0.3
Medium M 0.3 to 1
High H 1 to 3
Very High VH 3 to 10
Extremely High EH >10
Diametral Point Load Index test
Axial Point Load Index test
DEFECT SPACING/BEDDING THICKNESS
Measured at right angles to defects of same set or bedding.
Term Defect Spacing Bedding
Extremely closely spaced <6 mm
6 to 20 mm
Thinly Laminated
Laminated
Very closely spaced 20 to 60 mm Very Thin
Closely spaced 0.06 to 0.2 m Thin
Moderately widely spaced 0.2 to 0.6 m Medium
Widely spaced 0.6 to 2 m Thick
Very widely spaced >2 m Very Thick
DEFECT DESCRIPTION
Type: Definition:
B Bedding
BP Bedding Parting
F Fault
C Cleavage
J Joint
SZ Shear Zone
CZ Crushed Zone
DB Drill Break
Planarity: Roughness:
P – Planar R – Rough
Ir – Irregular S – Smooth
St – Stepped Sl – Slickensides
U – Undulating Po – Polished
Coating or Infill: Description
Clean No visible coating or infilling
Stain No visible coating or infilling but surfaces are
discoloured by mineral staining
Veneer A visible coating or infilling of soil or mineral
substance but usually unable to be measured (<1mm).
If discontinuous over the plane, patchy veneer
Coating A visible coating or infilling of soil or mineral
substance, >1mm thick. Describe composition and
thickness
The inclinations of defects are measured from perpendicular to the core axis.
© ESWNMAN Pty Ltd 3
Graphic Symbols for Soil and Rock Graphic symbols used on borehole and test pit reports for soil and rock are as follows. Combinations of these symbols may be used to indicate mixed materials such as
clayey sand.
© ESWNMAN Pty Ltd 4
Engineering classification of shales and sandstones in the Sydney
Region - A summary guide
The Sydney Rock Class classification system is based on rock strength, defect spacing and allowable seams as set out below. All three factors
must be satisfied.
CLASSIFICATION FOR SANDSTONE
Class Uniaxial Compressive
Strength (MPa)
Defect Spacing
(mm)
Allowable Seams
(%)
I >24 >600 <1.5
II >12 >600 <3
III >7 >200 <5
IV >2 >60 <10
V >1 N.A. N.A.
CLASSIFICATION FOR SHALE
Class Uniaxial Compressive
Strength (MPa)
Defect Spacing
(mm)
Allowable Seams
(%)
I >16 >600 <2
II >7 >200 <4
III >2 >60 <8
IV >1 >20 <25
V >1 N.A. N.A.
1. ROCK STRENGTH
For expedience in field/construction situations the uniaxial (unconfined) compressive strength of the rock is often inferred, or assessed using the
point load strength index (Is50) test (AS 4133.4.1 - 1993). For Sydney Basin sedimentary rocks the uniaxial compressive strength is typically
about 20 x (Is50) but the multiplier may range from about 10 to 30 depending on the rock type and characteristics. In the absence of UCS tes ts,
the assigned Sydney Rock Class classification may therefore include rock strengths outside the nominated UCS range.
2. DEFECT SPACING
The terms relate to spacing of natural fractures in NMLC, NQ and HQ diamond drill cores and have the following definitions:
Defect Spacing (mm) Terms Used to Describe Defect Spacing1
>2000 Very widely spaced
600 – 2000 Widely spaced
200 – 600 Moderately spaced
60 – 200 Closely spaced
20 – 60 Very closely spaced
<20 Extremely closely spaced
1After ISO/CD14689 and ISRM.
3. ALLOWABLE SEAMS
Seams include clay, fragmented, highly weathered or similar zones, usually sub-parallel to the loaded surface. The limits suggested in the
tables relate to a defined zone of influence. For pad footings, the zone of influence is defined as 1.5 times the least foot ing dimension. For
socketed footings, the zone includes the length of the socket plus a further depth equal to the width of the footing. For tunnel or excavation
assessment purposes the defects are assessed over a length of core of similar characteristics.
Source: Based on Pells, P.J.N, Mostyn, G. and Walker, B.F. (1998) – Foundations on sandstone and shale in the Sydney region. Australian
Geomechanics Journal, No 33 Part 3
© ESWNMAN Pty Ltd
APPENDIX D
___________________________________
CORE PHOTOGRAPHS
Sheet 1 of 1
Prepared: J.L.
Date: 26/06/2017
Weyand Pty Ltd
Geotechnical Investigation
105 Cudgegong Road, Rouse
Hill, NSW 2155
Ref No: ESWN-PR-2017-118
BH3: 3.0m to 7.0m
BH4: 6.1m to 9.0m
CORING STARTS AT 3.0m
Core Box Photographs
END OF HOLE AT 7.0m
3
4
6
7
CORING STARTS AT 6.1m
END OF HOLE AT 9.0m
8
5
6
CORE LOSS
CORE LOSS
© ESWNMAN Pty Ltd
APPENDIX E
___________________________________
RESULTS OF POINT LOAD
STRENGTH INDEX(IS50)
Note 1: To utilise this spreadsheet, insert values obtained from the point load test into the highlighted columns
No. BH No.Depth
(m)D (mm)
Pindicated
(kN)
Pactual
(kN)
De2
(mm2)
De
(mm)Is F Is(50)
W
(mm)L (mm)
Pindicated
(kN)
Pactual
(kN)
De2
(mm2)
De
(mm)Is F Is(50) Strength
Qu
(by 20)
MPa
1 BH3 3.80 50 8.52 8.53 2500 50 3.410 1.000 3.41 50 80 6.88 6.88 5093 71.36 1.35 1.19 1.61 32
2 4.25 50 2.51 2.50 2500 50 1.001 1.000 1.00 50 80 3.62 3.62 5093 71.36 0.71 1.19 0.85 16
3 6.35 50 3.80 3.80 2500 50 1.518 1.000 1.52 50 80 6.30 6.30 5093 71.36 1.24 1.19 1.48 29
4 BH4 6.55 50 0.22 0.21 2500 50 0.083 1.000 0.08 50 80 2.37 2.36 5093 71.36 0.46 1.19 0.55 11
5 7.25 50 3.83 3.83 2500 50 1.530 1.000 1.53 50 80 6.44 6.44 5093 71.36 1.26 1.19 1.51 30
6 8.20 50 1.66 1.65 2500 50 0.661 1.000 0.66 50 80 3.33 3.32 5093 71.36 0.65 1.19 0.78 15
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Diametral
Job No.
Job Description:
Location:
ESWN-PR-2017-118
105 Cudgegong Road, Rouse Hill, NSW 2155
Axial
Date 6/06/2017
Site Test:
POINT LOAD TEST
Tested by:
Checked by:
Y.N.
J.L.Geotechnical Investigation
Lab
_________________________________________________________________________ © ESWNMAN Pty Ltd
APPENDIX F
___________________________________
RESULTS OF LABORATORY TEST
Accreditation No. 2562
Date Reported
Contact
SGS Alexandria Environmental
Unit 16, 33 Maddox St
Alexandria NSW 2015
Huong Crawford
+61 2 8594 0400
+61 2 8594 0499
2
SGS Reference
Facsimile
Telephone
Address
Manager
Laboratory
(Not specified)
DDE-105
(Not specified)
(Not specified)
Unit 5, 15 Aero Rd
Ingleburn
BUXTON NSW 2565
DIRT DOCTORS GEOTECHNICAL TESTING SERVICES PTY LTD
MITCHELL TOFLER
Samples
Order Number
Project
Facsimile
Telephone
Address
Client
CLIENT DETAILS LABORATORY DETAILS
8/6/2017
ANALYTICAL REPORT
SE166156 R2
Date Received 2/6/2017
COMMENTS
Accredited for compliance with ISO/IEC 17025-Testing. NATA accredited laboratory 2562(4354).
This report cancels and supersedes the report No .SE166156R1. dated 5/6/17 issued by SGS Environment, Health and Safety due to spliting of
report.
Dong Liang
Metals/Inorganics Team Leader
Ly Kim Ha
Organic Section Head
SIGNATORIES
Member of the SGS Group
www.sgs.com.aut +61 2 8594 0400
f +61 2 8594 0499
Australia
Australia
Alexandria NSW 2015
Alexandria NSW 2015
Unit 16 33 Maddox St
PO Box 6432 Bourke Rd BC
Environment, Health and SafetySGS Australia Pty Ltd
ABN 44 000 964 278
Page 1 of 68/06/2017
SE166156 R2ANALYTICAL RESULTS
pH in soil (1:5) [AN101] Tested: 5/6/2017
E2
SOIL
-
30/5/2017
SE166156.002
pH pH Units - 4.9
UOMPARAMETER LOR
Page 2 of 68/06/2017
SE166156 R2ANALYTICAL RESULTS
Conductivity and TDS by Calculation - Soil [AN106] Tested: 5/6/2017
E2
SOIL
-
30/5/2017
SE166156.002
Conductivity of Extract (1:5 dry sample basis) µS/cm 1 460
UOMPARAMETER LOR
Page 3 of 68/06/2017
SE166156 R2ANALYTICAL RESULTS
Soluble Anions (1:5) in Soil by Ion Chromatography [AN245] Tested: 5/6/2017
E2
SOIL
-
30/5/2017
SE166156.002
Chloride mg/kg 0.25 540
Sulphate mg/kg 5 110
UOMPARAMETER LOR
Page 4 of 68/06/2017
SE166156 R2ANALYTICAL RESULTS
Moisture Content [AN002] Tested: 5/6/2017
E2
SOIL
-
30/5/2017
SE166156.002
% Moisture %w/w 0.5 7.7
UOMPARAMETER LOR
Page 5 of 68/06/2017
SE166156 R2METHOD SUMMARY
METHOD METHODOLOGY SUMMARY
The test is carried out by drying (at either 40°C or 105°C) a known mass of sample in a weighed evaporating
basin. After fully dry the sample is re-weighed. Samples such as sludge and sediment having high percentages of
moisture will take some time in a drying oven for complete removal of water.
AN002
pH in Soil Sludge Sediment and Water: pH is measured electrometrically using a combination electrode and is
calibrated against 3 buffers purchased commercially. For soils, sediments and sludges, an extract with water (or
0.01M CaCl2) is made at a ratio of 1:5 and the pH determined and reported on the extract. Reference APHA
4500-H+.
AN101
Conductivity and TDS by Calculation: Conductivity is measured by meter with temperature compensation and is
calibrated against a standard solution of potassium chloride. Conductivity is generally reported as µmhos /cm or
µS/cm @ 25°C. For soils, an extract with water is made at a ratio of 1:5 and the EC determined and reported on
the extract, or calculated back to the as-received sample. Salinity can be estimated from conductivity using a
conversion factor, which for natural waters, is in the range 0.55 to 0.75. Reference APHA 2510 B.
AN106
Anions by Ion Chromatography: A water sample is injected into an eluent stream that passes through the ion
chromatographic system where the anions of interest ie Br, Cl, NO2, NO3 and SO4 are separated on their relative
affinities for the active sites on the column packing material. Changes to the conductivity and the UV -visible
absorbance of the eluent enable identification and quantitation of the anions based on their retention time and
peak height or area. APHA 4110 B
AN245
FOOTNOTES
*
**
NATA accreditation does not cover
the performance of this service.
Indicative data, theoretical holding
time exceeded.
-
NVL
IS
LNR
Not analysed.
Not validated.
Insufficient sample for analysis.
Sample listed, but not received.
Samples analysed as received.
Solid samples expressed on a dry weight basis.
Where "Total" analyte groups are reported (for example, Total PAHs, Total OC Pesticides) the total will be calculated as the sum of the individual
analytes, with those analytes that are reported as <LOR being assumed to be zero. The summed (Total) limit of reporting is calculated by summing
the individual analyte LORs and dividing by two. For example, where 16 individual analytes are being summed and each has an LOR of 0.1 mg/kg,
the "Totals" LOR will be 1.6 / 2 (0.8 mg/kg). Where only 2 analytes are being summed, the " Total" LOR will be the sum of those two LORs.
Some totals may not appear to add up because the total is rounded after adding up the raw values.
If reported, measurement uncertainty follow the ± sign after the analytical result and is expressed as the expanded uncertainty calculated using a
coverage factor of 2, providing a level of confidence of approximately 95%, unless stated otherwise in the comments section of this report.
Results reported for samples tested under test methods with codes starting with ARS -SOP, radionuclide or gross radioactivity concentrations are
expressed in becquerel (Bq) per unit of mass or volume or per wipe as stated on the report. Becquerel is the SI unit for activity and equals one
nuclear transformation per second.
Note that in terms of units of radioactivity:
a. 1 Bq is equivalent to 27 pCi
b. 37 MBq is equivalent to 1 mCi
For results reported for samples tested under test methods with codes starting with ARS -SOP, less than (<) values indicate the detection limit for
each radionuclide or parameter for the measurement system used. The respective detection limits have been calculated in accordance with ISO
11929.
The QC criteria are subject to internal review according to the SGS QAQC plan and may be provided on request or alternatively can be found here :
http://www.sgs.com.au/~/media/Local/Australia/Documents/Technical%20Documents/MP-AU-ENV-QU-022%20QA%20QC%20Plan.pdf
This document is issued by the Company under its General Conditions of Service accessible at www.sgs.com/en/Terms-and-Conditions.aspx.
Attention is drawn to the limitation of liability, indemnification and jurisdiction issues defined therein.
Any holder of this document is advised that information contained hereon reflects the Company 's findings at the time of its intervention only and
within the limits of Client's instructions, if any. The Company's sole responsibility is to its Client only. Any unauthorized alteration, forgery or
falsification of the content or appearance of this document is unlawful and offenders may be prosecuted to the fullest extent of the law .
This report must not be reproduced, except in full.
UOM
LOR
↑↓
Unit of Measure.
Limit of Reporting.
Raised/lowered Limit of
Reporting.
Page 6 of 68/06/2017
_________________________________________________________________________ © ESWNMAN Pty Ltd
APPENDIX G
___________________________________
LIMITATIONS OF GEOTECHNICAL
INVESTIGATION
ESWNMAN PTY LTD ABN 70 603 089 630
Limitations of Geotechnical Investigation
1 | P a g e
General
In making an assessment of a site from a limited number of boreholes or test pits there is the
possibility that variations may occur between testing locations. Site exploration identifies specific
subsurface conditions only at those points from which samples have been taken. The risk that
variations will not be detected can be reduced by increasing the frequency of testing locations. The
investigation program undertaken is a professional estimate of the scope of investigation required
to provide a general profile of the subsurface conditions. The data derived from the site
investigation program and subsequent laboratory testing are extrapolated across the site to form an
inferred geological model and an engineering opinion is rendered about overall subsurface
conditions and their likely behaviour with regard to the proposed development. Despite
investigation the actual conditions at the site might differ from those inferred to exist, since no
subsurface exploration program, no matter how comprehensive, can reveal all subsurface details and anomalies.
The borehole/test pit logs are the subjective interpretation of subsurface conditions at a particular
location, made by trained personnel. The interpretation may be limited by the method of investigation, and cannot always be definitive.
Subsurface conditions
Subsurface conditions may be modified by changing natural forces or man-made influences. A geotechnical report is based on conditions which existed at the time of subsurface exploration.
Construction operations at or adjacent to the site, and natural events such as rainfall events, floods,
or groundwater fluctuations, may also affect subsurface conditions, and thus the continuing
adequacy of a geotechnical report. The geotechnical engineer should be kept appraised of any such events, and should be consulted to determine if additional tests are necessary.
Assessment and interpretation
A geotechnical engineer should be retained to work with other appropriate design professionals
explaining relevant geotechnical findings and in reviewing the adequacy of their drawings/plans and specifications relative to geotechnical issues.
Information and documentations
Final logs are developed by geotechnical engineers based upon their interpretation of field
description and laboratory results of field samples. Customarily, only the final logs are included in
geotechnical engineering reports. These logs should not under any circumstances be redrawn for
inclusion in architectural or other design drawings. To minimise the likelihood of bore/profile log
misinterpretation, contractors should be given access to the complete geotechnical engineering
report prepared or authorised for their use. Providing the best available information to contractors helps prevent costly construction problems.
Construction phase service (CPS)
During construction, excavation is frequently undertaken which exposes the actual subsurface
conditions. For this reason geotechnical consultants should be retained through the construction
stage, to identify variations if they are exposed and to conduct additional tests which may be
required and to deal quickly with geotechnical problems if they arise.
ESWNMAN PTY LTD ABN 70 603 089 630
Limitations of Geotechnical Investigation
2 | P a g e
Report
The report has been prepared for the benefit of the client and no other parties. ESWNMAN PTY
LTD assumes no responsibility and will not be liable to any other person or organisation for or in
relation to any matter dealt with or conclusions expressed in the report, or for any loss or damage
suffered by any other person or organisation arising from matters dealt with or conclusions
expressed in the report (including without limitation matters arising from any negligent act or
omission of ESWNMAN PTY LTD or for any loss or damage suffered by any other party relying
upon the matters dealt with or conclusions expressed in the report). Other parties should not rely
upon the report or the accuracy or completeness of any conclusions and should make their own enquiries and obtain independent advice in relation to such matters.
Other limitations
ESWNMAN PTY LTD will not be liable to update or revise the report to take into account any
events or emergent circumstances or facts occurring or becoming apparent after the date of the report.