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Geotechnical Investigation
[email protected]
arcosgroup.com.au
ABN 51 640 311 841
Attention: Sonja Heron 31 May 2022
By Email ARCOS PROJECT:220329
Report 01 Revision Rev A
Report on Geotechnical Investigation
Proposed Residential Dwelling
36 Riverpark Drive, Ringtail Creek
Arcos Unit Group Pty Ltd (Arcos Group) has undertaken a geotechnical investigation for the above project and client.
SUMMARY OF INVESTIGATION
Results of Australian Geomechanic Society Landslide Risk Assessment
Low to Moderate*
Note: The above is a summary of the detailed investigation results discussed within this report. The entire report must be read,
understood and kept in entirety. * See Section 6 for details
Geotechnical Engineer Principal Geotechnical Engineer
Cody Surawski B.Eng (Civ)(Hons), B.Env.Sc Billy Blake B.Eng (Civ)(Hons), MIEAust, RPEQ,
CPEng, NER
[email protected] [email protected]
For and On Behalf of Arcos Group For and on Behalf of Arcos Group
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1 INTRODUCTION
Arcos Unit Group Pty Ltd (Arcos Group) was commissioned to undertake a geotechnical investigation for the project
at the location described on the title page of this report.
This report outlines the results of the investigation, laboratory testing, analysis, and interpretive reporting on the
following items:
Review of the existing slope stability hazards, their attributed risks and impacts of the proposed development in
alignment with the practices set out within the Australian Geomechanics Society guidelines; and,
Provide recommendations from a geotechnical context that will avoid or reduce any potential instability.
This report must be kept in entirety. The use of this document is exclusively undertaken in accordance with our terms
and conditions.
2 REGIONAL GEOLOGY
The site is located on the border between two geological units, as shown in Figure 1. The location of the proposed
dwelling is underlain by Quaternary aged Tiaro Coal Measures, which typically comprises “Clay, silt, sand and gravel;
flood-plain alluvium”, while the lower side of the batter is underlain by Quaternary aged deposits, typically comprising
“Mud, muddy sand, sand and minor peat; swamp and heath deposits in coastal areas”. The encountered material is
in general agreement with the predicted geological units.
FIGURE 1: REGIONAL GEOLOGY
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3 EXISTING STABILITY RISK
Local authorities prepare mapping tools to aid in assessing potential slope stability requirements. The mapping tools
are a “high level” approach where the site specific investigations are specific to a particular site/allotment. It is
important to note that where a site specific investigation and slope stability assessment are undertaken, they take
precedence.
Reference to the available overlays for the area show the site has been initially mapped as “Moderate” in terms of
landslide hazard.
4 GEOTECHNICAL INVESTIGATION
A previous geotechnical investigation was undertaken by Global Testing Pty Ltd (Global) for the purposes of a site
classification. As part of this investigation, Global undertook the drilling of four boreholes around the proposed
location of the dwelling, on the high side of the batter. The encountered material consisted of clay fill overlying natural
stiff clays, increasing to very stiff clay at depth. No groundwater was noted in their borehole logs. Global’s previous
investigation is attached to this report, and has been used to form part of the analysis undertaken by Arcos. An
additional test pit was excavated at a later date, with the soil logged by a Geotechnical Engineer from Arcos. The
test pit log can be found attached, however in summary, the encountered soil profile was consistent with the findings
from Global. Additionally, the material at the base of the batter was assessed by Arcos, where silty sandy clay was
encountered, with a higher moisture content.
5 WALKOVER ASSESSMENT
Geotechnical comments are based on the factual findings of the investigation, best practice, local experience,
published correlations; however, are fundamentally founded in opinion and this should be considered.
A site walkover assessment was undertaken by a Geotechnical Engineer on 27 April 2022. The proposed dwelling
location is positioned towards the northern end of the property in a cleared pad. The house pad is relatively flat with
an approximately 9 m high batter on the northern side sloping down to meet with alluvial plains running alongside the
river. The slope angle of the batter varies from approximately 20° up to approximately 35°. No obvious signs of
disturbed ground, tension cracks or hummocks were noted in the vicinity of the proposed residence during the
walkover assessment. Some surficial soil creep was noted in the steeper parts of the slope where the water flow
paths were present. Based on the nearby river and dam, as well as overly moist soils at the base of the batter, it is
presumed that the standing water table is approximately 1 m below the existing ground level at the base of the batter.
6 AGS ASSESSMENT
Landslides are caused where a soil or rock mass has a decrease in strength, usually attributed to groundwater,
resulting in the material not being able to maintain its own self-weight resulting in a slope failure.
The Australian Geomechanics Society (AGS) developed a set of tools and procedures for assessing the stability of
a slope. The tools and procedures presented with the AGS documentation form the basis of the assessment
undertaken herein and their documentation is attached for reference.
The guidelines also identify that the regulator typically sets the standard for levels of tolerable risk. AGS defines
tolerable risk as “risks within a range that society can live with so as to secure certain benefits. It is a range of risk
regarded as non-negligible and needing to be kept under review and reduced further if practicable”.
The guides suggest that areas of moderate or greater risk should not be developed unless a rigorous remediation
plan be implemented to reduce the area to a level of Acceptable Risk. AGS defines acceptable risk as “risk which
everyone affected is prepared to accept. Action to further reduce such risk is usually not required unless reasonably
practicable measures are available at low cost in terms of money, time and effort.”.
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AGS suggest that regulators generally accept risk levels of “low” or lower as a level of acceptable risk.
AGS prepared a semi-quantitative assessment tool for determining the level of risk for a site. The tool separates the
potential hazards for a site, from a stability context, and rates them with a level of risk frequency. The multiplication
of these individual risk frequency summates as the risk frequency rating which is then measured against the levels
of risk nominated by AGS.
The results of this analysis are shown in Table 1.
TABLE 1: AGS ASSESSMENT
Hazard Likelihood Consequence Risk Level
Global Failure Possible Minor Moderate
Creep in Shallow Soils Likely Insignificant Low
Rotational or translational slide down Possible Minor Moderate
the slope
Based on the results of the AGS assessment, the perceived risk based on the conditions encountered and information
available at the time of the assessment is “Moderate” for the current proposed construction. Where proposed
structures are set back a minimum of 1m from the edge of the slope batter the risk rating may be reduced to “Low”.
7 HILLSIDE CONSTRUCTION
The following works should be implemented in addition to other items highlighted within this document. These points
are considered to be typical good hillside construction practice as explained in attached documentation:
All footings should be found in natural materials and should extend to a depth which will not adversely effect the
existing battered slope.
Fill should be limited to no more than 1 m and should be step keyed into the existing slope. The fill should be
formed at no steeper than 3H:1V, unless retained by an engineered retention system. All fill should be placed in
accordance with AS3798.
Where slopes are not supported by an engineer designed support system, natural slopes within or near movement
sensitive areas should be no steeper than 2.5H:1V.
All stormwater and surface water is to be discharged by an approved stormwater drainage system. The use of
subsurface drainage systems are not suitable unless greater than 50 m downslope from the envelope at this site.
Ongoing maintenance of effluent wastewater areas are also considered mandatory. The location of the application
area should be located below the proposed building.
Plumbing and services must also not be allowed to leak and regular maintenance and inspections should be
undertaken.
Erosion protection of cut and fill batters will be required. Batters should incorporate crest and toe drainage.
Batters should be vegetated appropriately to minimise erosion.
Overland flow paths will need to be carefully directed to approved outlets to minimise erosion.
8 GEOTECHNICAL RECOMMENDATIONS
The following sections details specific geotechnical constraints or recommendations in addition to general hillside
construction notes.
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8.1 FOOTINGS
In accordance with industry standards, a geotechnical engineer from Arcos should undertake the testing within the
footings to confirm that the encountered material is in alignment with the adopted parameters and assumptions
provided within this report. Where this does not occur, Arcos cannot be held liable for any of the information presented
within this report.
All footings will need to be designed to accommodate potential ground surface movement, settlement values and
any additional settlement values associated with the placement of new fill.
Settlement for suitably sized and designed high level footings should be in the order of 1-2% of the width of the
footing.
If footings are located adjacent to an underground service or other obstruction that is not homogenous with the
founding strata, the footing should be extended a minimum 0.3 m below an imaginary line projected at a 45 degree
angle from the lowest point of the service/obstruction. This is depicted graphically for reference:
The ultimate geotechnical end bearing and shaft adhesion parameters are presented in Table 2. The values given
will need to reduced by applying a suitable geotechnical strength reduction factor (Φg) for limit state or divided by a
suitable factor of safety for working stress methods. The Φg should be selected by the designer.
Based on the conditions encountered, high level footings or bored piles would be considered suitable
TABLE 2: DEEP LEVEL FOOTING – ULTIMATE GEOTECHNICAL PARAMETERS (LONG PILE)
Material Bored Bored
Fb (kPa) Fs (kPa)
Stiff Clay 450 20
Very Stiff Clay 900 45
Notes: Fb = Base Bearing (Ultimate); Fs = Shaft Adhesion (Ultimate)
The upper 1 m of soil profile should be ignored in shaft calculations for bored piles to allow for shrinkage cracks. Due
to installation disturbance, shaft adhesion should be ignored for steel screw piles. The values presented in Table 3
assume that the material equal to four pile diameters below the base of any footings is as strong or stronger.
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Settlement values are subjected to a variety of factors; however, a properly designed and constructed pile should
have a serviceability settlement between 1% and 2% of its’ diameter.
8.2 TEMPORARY BATTER SLOPES
It is understood that a basement is to be constructed as part of the proposed residential dwelling. Therefore, it is
likely that temporary batter slopes will be required, with personnel working at the base of the excavations.
Near vertical temporary excavations less than 1.5 m depth in dry clay soils are likely to be suitable for short term
footing construction, excavation and construction of a basement, or installations of underground services provided
there are no sensitive services or structures, or vehicular trafficked areas located close to the excavation crest.
All excavations greater than 1.5 m depth will need to be benched or battered for stability and prior to personnel
entering the excavation.
Suitable unsurcharged temporary and permanent dry batter slopes for excavations up to 3 m in height in in stiff or
stronger clay soils can be formed at a slope of 1H:1V (short term), however should be confirmed by a geotechnical
engineer at the time of excavation. Where groundwater seepage is encountered, batter slopes will need to be
considerably flatter.
8.3 ACID SULFATE SOILS
Acid sulfate soils (ASS) are coastal and near-coastal soils, sediments or other materials containing iron sulfides.
They are environmentally benign when left undisturbed in an aqueous, anoxic environment, but when exposed to
oxygen the iron sulfides break down, releasing sulfuric acid and soluble iron. Both substances have considerable
ability to degrade the natural and built environment, and the acid may additionally mobilise other pollutants (ie.
aluminium, lead, zinc) if present in the soil.
Previous experience and available guidelines indicate that ASS are normally restricted in extent to recent
(Holocene to Pleistocene age) soil horizons deposited in a saline environment below RL 5 m.
ASS includes actual acid sulfate soils (AASS) and potential acid sulfate soils (PASS). AASS and PASS are often
found within the same soil profile, with AASS generally overlying PASS. AASS are highly acidic resulting from the
oxidation of soil materials that contained sulfides. PASS are soils that contain iron sulfides or sulfidic materials,
which have not yet been oxidised.
Based on the QASSIT guidelines, the following criteria was adopted to determine the presence of acid sulfate soils:
• pHf of less than 4 indicates oxidation of sulfides has probably occurred in the past, indicating the presence of
actual acidity (AASS).
• pHf between 4 and 5.5 indicates the soils are acidic. This may be as a result of limited oxidation of sulfides, but
may also be as a consequence of the presence of organic acids.
• pHf of greater than 5.5 indicates the soil has little or no actual acidity; however this can be common with PASS
materials or marine-influenced samples.
The pHf test method does not detect acidity bound within sulfides; however the pHfox test gives an indication of any
potential acid release. Results of the pHfox are summarised as follows:
• pHfox of less than 3, plus a pHfox reading at least one pH unit below pHf, plus a strong reaction with peroxide,
strongly indicates the presence of PASS.
• pHfox between 3 and 4 indicates the possibility of PASS material and a pHfox between 4 and 5 may indicate the
presence of small amounts of sulfide or fine carbonates.
• pHfox of greater than 5 indicates that PASS material is unlikely.
To provide confirmation of the above qualitative testing, quantitative analytical testing was carried out on selected
samples, generally with the greatest difference in pHf and pHfox readings and strongest reaction to peroxide using
the Chromium Suite method.
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• The chromium reducible sulfur values (SCR) where greater than 0.01 %S indicates a significant level of sulfide,
and where greater than 0.03 %S then the soil has a potential acidity level exceeding the QASSIT guideline value.
• Where the total actual acidity (TAA) value exceeds 18 mol/t then the soil has an acidity level exceeding the
QASSIT guideline value.
• Where the sulfur in KCl extract values (SKCl) is less than 0.01 %S, then the soil has little or no history of sulfide
oxidation. A low SKCl combined with a low SCR indicates the soil is not an acid sulfate soil and further development
of acid is likely to be low.
Generally, the action criterion from the chromium suite of tests, which triggers a requirement for ASS disturbance to
be managed, derived from the Soil Management Guidelines is as follows:
• Net Acidity (TAA + SCR + SNAS) of greater than or equal to 0.03 %S for disturbances of greater than 1000 tonnes.
The action criterion was exceeded in no samples tested.
The complete treatment and neutralisation of the naturally occurring acidic soils is considered not necessary. The
acidity found naturally in non-ASS soils is not typically damaging to the environment and indeed the ecology. Some
environments are naturally acidic and support ecologies adapted to those acidic conditions.
ATTACHMENTS
About Your Geotechnical Report
Interpretation of the Subsurface Sheets
Client Supplied Information (Soil Report by others)
Test Pit Logs
Practice Note Guidelines for Landslide Risk Management
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ABOUT YOUR GEOTECH REPORT
Reporting
These notes have been provided to clarify and The report has been prepared and reviewed by
enhance the reader’s understanding of the suitably qualified and experienced persons. The
terminology used throughout the report, and also to persons draw on previous experience, local
identify where limitations exist. All investigations are knowledge, published literature, and otherwise
undertaken based on budgetary constraints which standard engineering approaches and principals. The
impart a level of uncertainty as a result of limiting the context of which the report has been prepared for must
amount of investigation undertaken. be considered and if the context changes, due
consideration should be given to the possibility that the
report is no longer considered relevant and review by
Copyright Arcos Unit Group Pty Ltd must be undertaken.
This report remains the property of Arcos Unit Group Arcos Unit Group Pty Ltd undertakes quality
Pty Ltd at all times unless ownership is transferred in assurance checks in accordance with its’ quality
writing. It cannot be included in any documentation system requirements; however, restrictions on the
without the express written permission of Arcos Unit project outside of Arcos Unit Group Pty Ltd’s control
Group Pty Ltd can result in unanticipated variations, changes in
policy or interpretation of said policies by the relevant
authority, or the actions of contractors subject to
Subsurface Report Sheets (Bores etc) commercial pressure.
The provided subsurface sheets are inherently an
interpretation undertaken by a suitably qualified and
experienced person; however, the reliability of the
Site Variations
provided information will rely on the method of If site variations become evident at the time of
investigation. It is prudent to state that these sheets construction or after the release of a report, Arcos Unit
only represent a very small percentage of the Group Pty Ltd requests immediately notification. This
subsurface conditions across a particular project. notification is proposed in order to assist in
remediation prior to any permanent structures or
It reasons that given the relatively small representation
design procedures are undertaken.
of the subsurface conditions for a project, spacial
variability between testing locations must be taken into
consideration including the orientation of strata Collaboration
intersections.
Arcos Unit Group Pty Ltd strongly recommends open
The presence or lack of groundwater is usually stated and collaborative communication about the use and
on the subsurface sheets; however, it must be noted inherent interpretation of Arcos Unit Group Pty Ltd’s
that the measurements undertaken onsite are typically report. Please contact the author of the report to
very inaccurate and if the presence or lack of arrange for an obligation free discussion regarding the
groundwater will have any degree of affect on the potential benefits of having geotechnical consultants.
project, additional groundwater monitoring techniques
should be employed such as groundwater monitoring
wells.
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Interpretation of the Subsurface Sheets
The terminology included on Arcos Unit Group Pty the most important component. Typically, the strength
Ltd’s has been evolved from AS1726:2016. Typically of rock is based on laboratory testing, tactile
a soil’s strength, colour, plasticity, grain size, other assessment and other observations as relevant. The
inclusions, and moisture will be described. A rock’s industry standard method for assessing the strength of
strength, weathering, colour, grain, and other rock in the field is to use the point load strength index
inclusions are typically described. (AS4133.4.1). It is important to note that the point load
strength index does not take into consideration the
degree of fracturing of a rock mass which can both
Soil lower and increase the overall rock strength. The
Soil is typically described by the components that strength of rock is broken down as follows:
make it up by percentage or whichever has a Very Low Strength (VLS) < 2 MPa (UCS)
governing behaviour. The types and sizes reproduced Low Strength (LS) 2 to 6 MPa (UCS)
from AS1726 are: Medium Strength (MS) 6 to 20 MPa (UCS)
Boulder >200 mm High Strength (HS) 20 to 60 MPa (UCS)
Cobble 63 to 200 mm Very High Strength (VHS) 60 to 200 MPa (UCS)
Gravel 2.36 to 63 mm Extremely High Strength (EHS) > 200 MPa (UCS)
Sand 0.075 to 2.36 mm Very Low Strength (VLS) < 0.1 Is(50)
Silty 0.002 to 0.075 mm Low Strength (LS) 0.1 to 0.3 Is(50)
Clay < 0.002 mm Medium Strength (MS) 0.30 to 1.0 Is(50)
The strength of soil is usually assessed by suitably High Strength (HS) 1.0 to 3.0 Is(50)
experienced persons through the use of laboratory Very High Strength (VHS) 3.0 to 10.0 Is(50)
test results, published literature, field assessments or Extremely High Strength (EHS) > 10.0 Is(50)
a combination of the above. The strength of soil is The Is(50) values are based on a correlation between
characterised into either cohesive (clays and silts) or the unconfined compressive strength (UCS) of 20.
cohesionless (sands and gravels) as shown below: This value varies significantly and site specific testing
Cohessive Soil Strength Term must take precedence.
Very Soft < 12.5 kPa Rock weathering is broken down as follows:
Soft 12.5 to 25 kPa Extremely weathered (EW) Behaves as soil but rock structure
Firm 25 to 50 kPa evident
Stiff 50 to 100 kPa Highly weathered (HW) Colour and strength of original fresh rock
is not recognisable. Decomposition of rock evident
Very Stiff 100 to 200 kPa
Moderately weathered (MW) Defects are heavily stained with
Hard > 200 kPa
rock mass showing signs of discolouration
Cohesionless Soils Strength Term (uncorrected Qc) Slightly weathered (SW) Some staining but minimal to no
Very Loose <2 MPa change in strength
Loose 2 to 5 MPa Fresh stained (FS) Minor staining evident
Medium Dense 5 to 15 MPa Fresh rock (FR) No change
Dense 15 to 25 MPa Rock fracturing is broken down as follows and can only
Very Dense > 25 MPa be accurately described where undamaged
continuous sampling has been undertaken:
Fragmented (Fg) Defect spacings < 20 mm
Rock
Highly Fractured (HF) Defect spacings 20 to 50 mm
Rock is typically described by the components that Fractured (Fr) Defect spacings 50 to 200 mm
make it up by percentage or whichever has a Slightly Fractured (SF) Defect spacings 200 to 1000 mm
governing behaviour. The strength of rock is typically Unbroken (Ub) Defect spacings > 1000 mm
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PH: 07 54 740 900
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[email protected]
QBCC 15288478
JOB NUMBER 21-1559 SITE CLASSIFICATION REPORT
CLIENT SONJA GLINSTER
SITE LOCATION PROPOSED DWELLING
36 RIVER PARK DRIVE, RINGTAIL CREEK.
REPORT DATE 21/03/2022
1. INTRODUCTION
The purpose of this report is to classify the subject allotment in accordance with Australian Standard
2870 - 2011 'Residential Slabs and Footings'. From this classification, a footing system can be recom-
mended for the structure so as to allow adequate performance of the footings under the soil conditions
determined at the site.
Trees: The classification herein excludes the effect of trees on the site.
2. SITE DESCRIPTION
Type of Allotment Acreage
Vegetation Grassed
Slope 5% to north-east (30% Slope Adjacent)
Surface Water will Drain Towards North-east
Will Surface Water from adjoining No
allotments traverse this site?
Surrounding Allotments
Left Acreage
Right Acreage
Rear Acreage
Depth to Weathered Rock BH1 (N/a), BH2 (N/a)
Depth to Water Table BH1 (N/a), BH2 (N/a)
3. SITE CLASSIFICATION AND TARGET STRATA
.Based on the findings of the site investigation, the classification of the site is considered to conform to:
CLASS “P” – (Due to Uncontrolled Fill - See Target Stratum)
PLEASE NOTE: If not for the above reasons, this site would have the characteristics of a Class H2 Site.
in accordance with Australian Standard 2870 - 2011, 'Residential Slabs and Footings, Construction'.
The Target Stratum for the design of the proposed structure at location BH1 is the SILTY
SANDY CLAY at a depth of 2200mm below existing ground surface. The Target Stratum for the
design of the proposed structure at location BH2 is the SANDY CLAY at a depth of 2900mm
below existing ground surface. The Target Stratum for the design of the proposed structure at
location BH3 is the SANDY CLAY at a depth of 3000mm below existing ground surface. The
Target Stratum for the design of the proposed structure at location BH4 is the SANDY CLAY at
a depth of 2700mm below existing ground surface.
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21-1559
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PH: 07 54 740 900
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[email protected]
QBCC 15288478
PLEASE NOTE: This report does not address slope stability. If a slope stability analysis is
required, the services of a suitably qualified geotechnical engineer should be sought.
We can recommend one or organise this service on your behalf.
It is the designing engineer’s responsibility to address the potential influence of any trees present
on or around the proposed building site.
If any further fill is placed over the existing ground, the structure shall be piered through the fill
into the existing material. Further note that the placement of reactive material as fill, or cutting
of the site may change the site’s classification.
4. SOIL PROFILE
Refer to Soil Profile Report for borelog information.
Whilst every effort has been made to ensure that the borelogs carried out at the subject allotment are
indicative of the soil profile over the site any discrepancy between the profile detailed in the borelogs
and that observed during construction shall be referred to Global Testing for immediate attention.
5. MATERIALS LABORATORY TEST RESULTS
Soil Laboratory testing carried out on samples of the soil taken from the site gave the following results:
BOREHOLE BH1
DEPTH RANGE OF SAMPLE 400-700mm
LIQUID LIMIT (%) N/a
PLASTIC LIMIT (%) N/a
PLASTIC INDEX (%) N/a
LINEAR SHRINKAGE (%) N/a
INSTABILITY INDEX (%) N/a
SHRINK SWELL INDEX, Iss (%) 5.4
PREDICTED SURFACE MOVEMENT N/a
Please note that the Plasticity Index (PI) determined by the Atterberg Test may be correlated to an
Instability Index (Ips)with reference to the results of extensive testing carried out by others, notably, Dr
P Mitchell, ‘Footings for Small Scale Domestic Structures,’ March 1990.
Yours Sincerely,
(Michael Pinkney - Office Manager-)
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21-1559
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PH: 07 54 740 900
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[email protected]
QBCC 15288478
LIMITATIONS
Recommendations given in this report are based on the information supplied by the client regarding the
proposed building construction in conjunction with the findings of the investigation. Any change in
construction type, building location or omission in the client supplied information, may require addi-
tional testing and/or make the recommendations invalid.
The recommendations herein identify a target soil stratum into which the footings are to be founded.
The target stratum has been located by the depth in mm of the target stratum's upper horizon boundary
below the existing ground surface level at the time of the site investigation. Any cutting or filling works
and any surface erosion or deposits subsequent to the site investigation, will alter the measured location
of the stratum relative to the surface. Where required, the author should be notified in such cases to
confirm the location of the target stratum.
The description of the soil given in the Soil Profile section of this report is intended as a brief overview
of the soil's primary constituents. For a detailed classification of the soil, the reader should refer to the
Soil Profile Reports and/or Borehole Reports attached to this report.
Every reasonable effort has been made to locate the test sites so that the borehole profiles are repre-
sentative of the soil conditions within the area investigated. The client should be made aware however,
that exploration is limited by time available and economic restraints. In some cases, soil conditions can
change dramatically over short distances, therefore, even careful exploration programs may not locate
all the variations.
If soil conditions different from those shown in this report are encountered or are inferred from other
sources, then the author must be notified immediately.
This report may not be reproduced except in full. The information and drawings provided with this
report shall only be used and will only be applicable for the development shown on the client supplied
information provided for this site.
Any dimensions, contours, slope directions and magnitudes shown on the Test Locality Plan shall not
be used for any building construction or costing calculations. The purpose of the plan is to show ap-
proximate location of field tests only.
Any changes made to these recommendations by persons unauthorised by the author will legally be
interpreted as that person assuming the responsibility for the long-term performance of the footing sys-
tem.
The recommendations contained in this report have not taken into consideration the long-term effects
of any previous, current or potential subsurface work by mining companies or potential slope instability
problems. At the time of writing this report neither our client (nor his agent) nor the local authority had
made the author aware that these problems may be affecting this allotment. If a mining subsidence or
slope stability assessment is required for this allotment, the recommendations of a suitably qualified
geotechnical engineer should be sought.
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21-1559
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PH: 07 54 740 900
3/53 Gateway Drive, Noosaville 4566
[email protected]
QBCC 15288478
SOIL PROFILE REPORT
CLIENT: SONJA GLINSTER AUTHORISED SONJA GLINSTER
BY:
PROJECT: 36 RIVER PARK DRIVE, DATE TESTED: 28/02/2022
RINGTAIL CREEK. JOB NO: 21-1559
Drilling Method: Jacro 105 100mm. Borehole
No.1
Depth Description PENET. Est. Bearing
(mm) (blows per Capacity
100mm) (kPa)
1 2 3 4
0 (FILL) SANDY CLAY (CI)-Medium plasticity,
grey-brown, fine to coarse sand, fine to coarse gravel,
moist, firm.
100 2 50
200 (FILL) SANDY CLAY (CI)-Medium plasticity, 3 100
grey-brown, fine to coarse sand, fine to coarse gravel,
moist, stiff.
300 4
400 SANDY CLAY (CH)-High plasticity, red/brown, pale 5
grey, fine to coarse sand, moist, stiff.
500 4 125
600 5
700 6 >200
800 6
900 5
1000 6 >200
1100 5
1200 6
1300 5
1400 5 150
1500 5
1600 6 >200
1700 6
1800 7
1900 7
2000 7
2100 7
2200 SILTY SAND CLAY (CH) High plasticity, brown,/ 10
pale grey, fine to coarse sand, moist, very stiff.
2300 19
2400 >20
2500
2600
2700
2800
2900
3000
3100
3200
3300
3400
3500 Hole Terminated
Page | 4 Borelogging in accordance with AS1726-2017 Geotechnical Site Investigations
21-1559
Page 14
PH: 07 54 740 900
3/53 Gateway Drive, Noosaville 4566
[email protected]
QBCC 15288478
SOIL PROFILE REPORT
CLIENT: SONJA GLINSTER AUTHORISED SONJA GLINSTER
BY:
PROJECT: 36 RIVER PARK DRIVE, DATE TESTED: 28/02/2022
RINGTAIL CREEK. JOB NO: 21-1559
Drilling Method: Jacro 105 100mm. Borehole
No.2
Depth Description PENET. Est. Bearing
(mm) (blows per Capacity
100mm) (kPa)
1 2 3 4
0 (FILL) SANDY CLAY (CI)-Medium plasticity, grey-
brown, fine to coarse sand, fine to coarse gravel, moist,
stiff.
100 3 100
200 3
300 3
400 SANDY CLAY (CH)-High plasticity, red/brown, pale 4 125
grey, fine to coarse sand, moist, stiff.
500 3
600 4
700 4
800 3 100
900 4
1000 4
1100 3
1200 4 125
1300 5
1400 5
1500 6 >200
1600 7
1700 7
1800 6
1900 6
2000 6 >200
2100 6
2200 7
2300 7
2400 8
2500 9
2600 9
2700 8
2800 9
2900 SANDY CLAY (CH)-High plasticity, red/brown, pale 10 >200
grey, fine to coarse sand, moist, very stiff.
3000 15
3100 >20
3200
3300
3400
3500 Hole Terminated
Page | 5 Borelogging in accordance with AS1726-2017 Geotechnical Site Investigations
21-1559
Page 15
PH: 07 54 740 900
3/53 Gateway Drive, Noosaville 4566
[email protected]
QBCC 15288478
SOIL PROFILE REPORT
CLIENT: SONJA GLINSTER AUTHORISED SONJA GLINSTER
BY:
PROJECT: 36 RIVER PARK DRIVE, DATE TESTED: 28/02/2022
RINGTAIL CREEK. JOB NO: 21-1559
Drilling Method: Jacro 105 100mm. Borehole
No.3
Depth Description PENET. Est. Bearing Ca-
(mm) (blows per pacity
100mm) (kPa)
1 2 3 4
0 (FILL) SANDY CLAY (CI)-Medium plasticity,
grey-brown, fine to coarse sand, fine to coarse gravel,
moist, stiff.
100 4 125
200 3
300 4
400 >20
500 - Pre-Drilled
600 SANDY CLAY (CH)-High plasticity, red/brown, pale -
grey, fine to coarse sand, moist, stiff.
700 -
800 -
900 -
1000 -
1100 -
1200 -
1300 -
1400 -
1500 -
1600 5 150
1700 7
1800 7
1900 7
2000 7
2100 7
2200 6 200
2300 7
2400 7
2500 7
2600 7
2700 7
2800 9
2900 9
3000 SANDY CLAY (CH)-High plasticity, red/brown, pale 10 >200
grey, fine to coarse sand, moist, very stiff.
3100 10
3200 11
3300 11
3400 11
3500 Hole Terminated 11
Page | 6 Borelogging in accordance with AS1726-2017 Geotechnical Site Investigations
21-1559
Page 16
PH: 07 54 740 900
3/53 Gateway Drive, Noosaville 4566
[email protected]
QBCC 15288478
SOIL PROFILE REPORT
CLIENT: SONJA GLINSTER AUTHORISED SONJA GLINSTER
BY:
PROJECT: 36 RIVER PARK DRIVE, DATE TESTED: 28/02/2022
RINGTAIL CREEK. JOB NO: 21-1559
Drilling Method: Jacro 105 100mm. Borehole
No.4
Depth Description PENET. Est. Bearing Ca-
(mm) (blows per 100mm) pacity
(kPa)
1 2 3 4
0 (FILL) SANDY CLAY (CI)-Medium plasticity,
grey-brown, fine to coarse sand, fine to coarse gravel,
moist, firm.
100 4 125
200 6 >200
300 8
400 7
500 6
600 SANDY CLAY (CI)-Medium plasticity, red/brown, 5 150
pale grey, fine to coarse sand, moist, stiff.
700 4
800 3
900 3 100
1000 4
1100 5
1200 5
1300 4
1400 5 150
1500 5
1600 6 >200
1700 7
1800 7
1900 8
2000 7
2100 6 200
2200 6
2300 9
2400 9
2500 SANDY CLAY (CH)-High plasticity, brown, fine to 6
coarse sand, moist, stiff.
2600 7
2700 SANDY CLAY (CH)-High plasticity, brown, fine to 11 >200
coarse sand, moist, very stiff.
2800 >20
2900
3000 SILTY SAND CLAY (CH) High plasticity, brown,/
pale grey, fine to coarse sand, moist, stiff.
3100
3200
3300
3400
3500 Hole Terminated
Page | 7 Borelogging in accordance with AS1726-2017 Geotechnical Site Investigations
21-1559
Page 17
PH: 07 54 740 900
3/53 Gateway Drive, Noosaville 4566
[email protected]
QBCC 15288478
Site- 36 RIVER PARK DRIVE, RINGTAIL CREEK.
Page | 8 Borelogging in accordance with AS1726-2017 Geotechnical Site Investigations
21-1559
Page 18
LEGEND
BHx = BOREHOLE LOCATION
TH
R
O PNx = DYNAMIC CONE
N PENETROMETER LOCATION
PTx = PERCOLATION TEST
=TREES
ADVANCED SECONDARY ASTP
TO BE INSTALLED IN A SUITABLE LOCATION
BY THE INSTALLING PLUMBER NOT ADJACENT
TO LIVING ROOMS OR BEDROOMS
6.0 LEVEL
5.0 7.0 RESERVE AREA
4.0 8.0
3.0 30% SLOPE 8.0
30% SLOPE
PN 3
BH 3
PN 1 K-RAIN VALVE (TO BE INSTALLED)
BH7
BH 1
9.0 40000 PT3
3.0
4.0 PN 4 PROPOSED RESIDENCE
BH 4
BH6
5.0 PT2 PROPOSED FIXED SURFACE SPRINKLER IRRIGATION
AREA = 360M2
PN 2 35 PLUMES REQUIRED
BH 2 TO BE PLANTED OUT WITH A MINIMUM OF 35 PLANTS,
MULCHED, BORDER AND INSTALL
24000
9.0
5% SLOPE
6.0
1800 3400
LEVEL BH5
PT1 FLUSH OUT VALVES
(TO BE INSTALLED)
1500 3000
15000
7.0
5% SLOPE
8.0
PPROX. EXTENT OF
IVEWAY
PREDOMINANT TREE
NG DR
9.0 LINE SHOWN SHADED
EXISTI
FIRE SOURCE
PPROX. EXTENT OF
PREDOMINANT TREE
LINE SHOWN SHADED
FIRE SOURCE
HEAVY DROPLET (PLUMES E.G 10MM FEEDER LINES)
TYP 150 HIGH MOUND SURROUND
PLUMES
1500 3000
300
SITE PLAN
SCALE: 1 : 350
25-32MM DIAMETER POLY LINES LAID BENEATH SURFACE. ULTILIZE EXISTING VEGETATION
TYP FIXED SPRAY SURFACE IRRIGATION SYSTEM
SITE CLASSIFICATION | EFFLUENT DESIGN CLIENT DETAILS PROJECT DETAILS SITE INFORMATION DRAWING TITLE JOB No. DRG No. REVISION
SUNSHINE COAST | BRISBANE | GOLD COAST
RPD: -
[email protected]
SONJA GLINSTER EFFLUENT DISPOSAL
SITE PLAN
21/1559 152 1
POSTCODE: 4565
COPYRIGHT © All rights reserved, this work is
copyright and cannot be reproduced or copied
LOT 2, 36 RIVER PARK DR, SUBURB: RINGTAIL CREEK
22/03/2022 FOR CONSTRUCTION AA 1
DATE DESCRIPTION BY REV
in any form without prior consent
RINGTAIL CREEK, QLD AUTHORITY: NOOSA SHIRE COUNCIL DRAWN: AA DESIGN: MP CHECK: GB DATE: 22/03/2022 SCALE: As indicated@A1
Page 19
CLIENT: Sonja Heron PROJECT #: 220329 BORE
PROJECT: Proposed Residential Dwelling
ADDRESS: 36 River Park Drive, Ringtail Creek
LOGGED: CS
1
EASTING: 498423 m
DRILL RIG: Excavator NORTHING: 7089075 m TEST DATE: 27/04/2022
Sampling & Testing
Graphic Log
DCP Results
Material Description Results &
Type (blows per 100 mm)
Comments
Water
RL Depth
(m) (m) 5 10 15 20
TOPSOIL Sandy CLAY CL: stiff, low plasticity, dark grey-brown, fine to medium grained sand,
W<PL (fill)
3
3
0.2
0.2 FILL Sandy CLAY CI: stiff, medium to high plasticity, orange-brown mottled red, fine to medium
grained sand, w<PL (fill)
4
D 3
4
0.5
0.5 Sandy CLAY CI: stiff to very stiff, medium to high plasticity, pale grey and orange-brown
mottled red, fine to medium grained sand, with silt, w<PL
5
5
D 5
5
5
1
1
6
6
D 6
7
6
1.5
7
7
D 7
7
2
2
medium plasticity
D
2.5
D
2.9
2.9 Bore Terminated at 2.9 m.
3
DRILLING METHOD: Excavator CASING: Nil
GROUNDWATER: no groundwater seepage noted at the time of investigation
REMARKS:
LEGEND:
D - Disturbed Sample from Auger SPT - Standard Penetration Test - Groundwater Seepage Level
B - Bulk Sample from Auger Is50 - Point Load Result (MPa) - Standing Groundwater Level
C - Rock Core PP - Pocket Penetrometer (kPa) - Partial Groundwater Loss
U50 - Undisturbed Sample (mm) - Perched Groundwater Level
Page 20
CLIENT: Sonja Heron PROJECT #: 220329 BORE
PROJECT: Proposed Residential Dwelling
ADDRESS: 36 River Park Drive, Ringtail Creek
LOGGED: CS
2
EASTING: 498495 m
DRILL RIG: Excavator NORTHING: 7089141 m TEST DATE: 27/04/2022
Sampling & Testing
Graphic Log
DCP Results
Material Description Results &
Type (blows per 100 mm)
Comments
Water
RL Depth
(m) (m) 5 10 15 20
Silty Sandy CLAY CI: stiff, medium to high plasticity, brown and red-brown, fine to medium
grained sand, w>PL
0.3 Bore Terminated at 0.3 m.
1
2
3
DRILLING METHOD: Excavator CASING: Nil
GROUNDWATER: no groundwater seepage noted at the time of investigation
REMARKS:
LEGEND:
D - Disturbed Sample from Auger SPT - Standard Penetration Test - Groundwater Seepage Level
B - Bulk Sample from Auger Is50 - Point Load Result (MPa) - Standing Groundwater Level
C - Rock Core PP - Pocket Penetrometer (kPa) - Partial Groundwater Loss
U50 - Undisturbed Sample (mm) - Perched Groundwater Level
Page 21
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ABN 51 640 311 842
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Sunshine Coast | Brisbane | Gold Coast
Sunshine Coast | Brisbane | Gold Coast
Page 23
ABN 51 640 311 842
arcosgroup.com.au
Sunshine Coast | Brisbane | Gold Coast
Sunshine Coast | Brisbane | Gold Coast
Page 24
ABN 51 640 311 842
arcosgroup.com.au
Sunshine Coast | Brisbane | Gold Coast
Sunshine Coast | Brisbane | Gold Coast
Page 25
ABN 51 640 311 842
arcosgroup.com.au
Sunshine Coast | Brisbane | Gold Coast
Contact Us
07 5293 7648
@arcosgroup
[email protected]
arcosgroup.com.au
Sunshine Coast | Brisbane | Gold Coast