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ADG1290.21 Dewatering Management Plan_Rev1_02.02.22 · OPW21/0315
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Dewatering Management Plan
Proposed Residential Development:
Lot 16 on N10576, 33 Wyuna Drive, Noosaville, Queensland
February 2022
Prepared for:
Michelle and Franco DePasquale
c/‐ Chris Clout Design
Acid Sulfate Soil Assessment On‐site Wastewater Management Contaminated Land Assessment & Remediation
Dewatering Management Environmental Management Plans Surface & Groundwater Investigation & Monitoring
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Report details
Project ref: ADG1290.21
ADG Project Contact: Michael Campbell
Report title: Dewatering Management Plan
Proposed Residential Development:
Lot 16 on N10576, 33 Wyuna Drive, Noosaville, Queensland
Version: Rev1.0
Author(s): David Knight
Reviewer: Michael Campbell
Client: Michelle and Franco DePasquale
c/‐ Chris Clout Design
Client contact: Joel Zauss
Distribution date: 02 February 2022
Distributed to: Chris Clout Design, SCG Consulting Engineers, Braeden Constructions
Copies: 1 PDF
ADG Consulting Pty Ltd
David Knight BEnvSc Michael Campbell BEnvSc, BSc[Hons],
MALGA DipProjMgt, DipOHS, DipBusMgt, DipBus(Quality Auditing)
Environmental Scientist MEIANZ, MALGA, MASSI
Director & Principal Environmental Scientist
Date: 02 February 2022
This document and all its content is copyright. Apart from fair dealing for the purposes of study, research, criticism
and/or review as permitted under the Copyright Act 1968, no part of the content may be reproduced, reused or
redistributed without the prior written permission of ADG Consulting Pty Ltd.
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Table of Contents
1 INTRODUCTION 1
1.1 PROPOSED DEVELOPMENT 1
1.2 RELEVANT GUIDELINES 1
1.3 GENERAL ENVIRONMENTAL DUTY 1
1.4 DMP OBJECTIVES 2
1.5 SCOPE OF WORK 2
2 SITE CHARACTERISTICS 3
2.1 PROPERTY DESCRIPTION 3
2.2 SURROUNDING ENVIRONMENT 3
2.3 TOPOGRAPHY 3
2.4 GEOLOGY & SOILS 3
2.5 HYDROGEOLOGY 3
3 PREVIOUS INVESTIGATIONS 4
3.1 DOUGLAS PARTNERS PTY LTD 2020 & 2022 4
3.1.1 SOILS 4
3.1.2 GROUNDWATER 4
3.2 GROUNDWATER QUALITY 6
4 WATER QUALITY OBJECTIVES 7
4.1 RECEIVING ENVIRONMENT 7
4.2 DEVELOPMENT OF WATER QUALITY OBJECTIVES 7
4.3 PROPOSED WATER QUALITY OBJECTIVES 8
5 DEWATERING METHODOLOGY 10
5.1 BASEMENT EXCAVATION AND SHORING 10
5.2 GROUNDWATER EXTRACTION 10
5.3 EXTRACTION/DISCHARGE RATES AND VOLUME 10
5.3.1 DEWATERING EXTRACTION CALCULATION BASED ON SUBSURFACE SOIL PROFILE 10
5.4 DEWATERING DURATION 11
5.5 GROUNDWATER DRAWDOWN 11
5.6 GROUNDWATER TREATMENT 11
5.7 NOMINATED HOLD POINTS 12
6 WATER QUALITY MANAGEMENT 13
6.1 RESPONSIBILITY 13
6.2 OPERATIONAL POLICY 13
6.3 PERFORMANCE CRITERIA 13
6.4 IMPLEMENTATION STRATEGY 13
6.4.1 GROUNDWATER TREATMENT SYSTEMS 13
6.4.2 DEWATERING STRATEGY 14
6.4.3 INITIAL PUMP‐OUT 14
6.5 MONITORING 14
6.5.1 VISUAL MONITORING 14
6.5.2 WATER QUALITY MONITORING 14
6.5.3 MONITORING RESPONSIBILITIES 15
6.6 MAINTENANCE 16
6.7 REPORTING 16
6.8 CONTINGENCIES 16
7 NOISE & ODOUR MANAGEMENT 18
7.1 RESPONSIBILITY 18
7.2 OPERATIONAL POLICY 18
7.3 PERFORMANCE CRITERIA 18
7.4 IMPLEMENTATION STRATEGY 18
7.4.1 NOISE 18
7.4.2 ODOUR 18
7.5 MONITORING 18
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7.6 REPORTING 19
7.7 CONTINGENCIES 19
8 LIMITATIONS 20
9 REFERENCES 21
APPENDIX A: FIGURES
APPENDIX B: DRDMW LICENCED BORE SEARCH
APPENDIX C: DEWATERING DETAILS PLAN (PRELIMINARY DRAFT)
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1 Introduction
ADG Consulting Pty Ltd (ADG) was engaged by Chris Clout Design (CCD) on behalf of Michelle and Franco
DePasquale to prepare a Dewatering Management Plan (DMP) for the proposed residential development
within property described as Lot 16 on N10576, situated at 33 Wyuna Drive, Noosaville, Queensland.
The original DMP (Rev 0, October 2021) has been revised (this Report, Rev 1.0) in response to an
Information Request issued by Noosa Council on 22 November 2021 (reference OPW21/0315).
1.1 Proposed development
The proposed development comprises the construction of a two‐storey apartment building over a single‐
level in‐ground basement carpark. Supplied information indicates that excavations to facilitate the
basement construction will extend to a maximum of approximately 3.1 m below existing ground level
(mbgl) to approximately ‐0.8 m Australian Height Datum (AHD). Localised deeper excavations may be
required for the construction of other structural elements (i.e. footings and pile caps), where required.
Groundwater seepage was recorded at between 1.65 to 2.35 mbgl (equating to approximate elevations
of 0.25 to 0.05 mAHD), during preliminary and follow‐up geotechnical works (drilling) on the site by
Douglas Partners in September 2020 and December 2021. Douglas Partners also undertook a follow‐up
standing water level gauging of 1.7 mbgl (equating to groundwater elevation of 0.2 mAHD) on 18 January
2021. Given the sites proximity to the Noosa River and the presence of groundwater, dewatering will be
necessary to allow the basement to be constructed in dry conditions.
1.2 Relevant guidelines
The DMP was prepared with reference to the following documents:
Australian and New Zealand Guidelines for Fresh and Marine Water Quality. 2018. Australian
and New Zealand Governments and Australian state and territory governments (ANZG),
Canberra ACT, Australia.
Australian and New Zealand Guidelines for Fresh and Marine Water Quality. 2000. Australian
and New Zealand Environment and Conservation Council and Agriculture and Resource
Management Council of Australia and New Zealand (ANZECC/ARMCANZ).
Environmental Protection (Water & Wetland Biodiversity) Policy 2019. Department of
Environment and Science (DES), Queensland Government.
Noosa River environmental values and water quality objectives. 2010. Department of
Environment and Resource Management (DERM), Queensland Government.
Guidelines for Managing Risks in Recreational Water. 2018. Australian Government, National
Health and Medical Research Council (NHMRC).
Monitoring and Sampling Manual 2018, Version 2 June 2018. 2018. Department of Environment
and Science (DES).
Queensland Water Quality Guidelines 2009, Version 3. 2013. The Department of Environment
and Heritage Protection (DEHP).
1.3 General environmental duty
The Environmental Protection Act 1994 describes that all persons in Queensland have a “General
Environmental Duty” and that “a person must not carry out an activity that causes, or is likely to cause
environmental harm unless the person takes all reasonable and practicable measures to prevent or
minimise the harm”.
The Act requires that appropriate action be taken to report that environmental harm is occurring or has
the potential to occur, unless the harm is authorised under an environmental protection policy, an
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environmental management program, a development approval, or an environmental protection order.
This is known as the “Duty to Notify”. Failure to fulfil this duty is an offence and may result in prosecution.
1.4 DMP objectives
The objectives of the DMP are to:
Describe the dewatering methodology, groundwater treatment, monitoring and reporting
procedures to be employed at the site during dewatering activities.
Provide effective management procedures to prevent environmental harm resulting from the
discharge of extracted groundwater from the site.
1.5 Scope of work
To achieve the investigation objectives, the following scope of work was undertaken:
A desktop study including:
1. Review of the development proposal and proposed shoring/dewatering designs.
2. Review of geology and soil maps for the area.
3. Search of groundwater bores licensed by the Department of Regional Development,
Manufacturing and Water (DRDMW) within a 500 m radius of the site.
4. Review of relevant existing reports and groundwater data from the local area.
5. Review of current aerial photographs of the site and surrounds.
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2 Site characteristics
2.1 Property description
The site is described as Lot 16 on N10576, and is situated at 33 Wyuna Drive, Noosaville, Queensland.
From most recent available aerial mapping dated 5 July 2021, the site contains a multi storey residential
dwelling planned for demolition and is generally rectangular in shape. The site has a combined area of
614.25 m2. The site locality is shown in Figure 1, Appendix A.
2.2 Surrounding environment
The surrounding environment and land use is described briefly in Table 1.
Table 1 Surrounding land use and environment
Direction Environment
North Noosa River.
East Single residential lot, then Noosa River.
South Wyuna Drive, then multiple residential lots.
West Multi residential lots, then Noosa River.
2.3 Topography
The site and surrounding land is considered to be generally level, with the site gently sloping towards the
Noosa River to the north with surface elevations ranging between approximately 2.4 m to 1.11 m AHD
from the southern boundary toward the north‐eastern corner of the site (Douglas Partners, Drawing No.
95120.00, Drawing No: 1, September 2020).
2.4 Geology & soils
The surface geology at the site is mapped as being Pleistocene aged sandy mud, muddy sand and minor
gravel: estuarine channels and banks. The dominant rock type is identified as miscellaneous
unconsolidated sediments as referenced through detailed surface geology (accessed via Queensland
Globe online, 10 September 2021)
The Acid Sulfate Soils (ASS) map 1:25,000 Redcliffe to Teewah – Map 2 categorises the site as ‘SDL’ or ‘Acid
Sulfate on Disturbed Land’, indicating that the site is likely to contain acid sulfate soils (and potential
exists that partial or full treatment may have been undertaken), however limited field investigation has
been performed in this area (DNRM 2002).
2.5 Hydrogeology
A search of groundwater bores licensed by DRDMW was conducted by ADG on 10 September 2021. The
search identified no licensed bores within a 500 m radius of the site. A map showing the bore search area
is provided in Appendix B.
Based on the local geology and topography, and the site’s proximity to the Noosa River, the inferred
groundwater flow is to the north. Groundwater beneath the site is likely to be hydraulically connected to
the river, therefore saline groundwater conditions are anticipated, and additional saltwater intrusion is
likely to occur during dewatering.
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3 Previous investigations
This DMP is based on site specific information sourced from the following, provided to ADG by Chris Clout
Designs:
Preliminary Geotechnical Investigation, Proposed Residence 33 Wyuna Drive, Noosaville. 2020.
Douglas Partners Pty Ltd. Ref: 95120.00.R.001.
Additional Geotechnical Investigation, Proposed Residence 33 Wyuna Drive, Noosaville. 2022.
Douglas Partners Pty Ltd. Ref: 95120.01.R.001.
It is noted that dilapidation reports for surrounding structures and services have been undertaken which
were not supplied to ADG for the purposes of preparing this DMP, however are to be provided to Council
separately from this DMP.
A brief discussion of relevant soil and groundwater conditions is provided below.
3.1 Douglas Partners Pty Ltd 2020 & 2022
A preliminary Geotechnical Investigation was undertaken at the site in September 2020 by Douglas
Partners Pty Ltd (DP), with an additional geotechnical and acid sulfate soil assessment undertaken in
December 2021.
3.1.1 Soils
Between the preliminary and additional investigations undertaken by DP, a total of four (4) boreholes
(BH1 – BH4) were drilled on the proposed development footprint to 6.0 mbgl.
The subsurface profile encountered is generally described as loose to medium dense brown, orange‐
brown grey sand fill to between 2.2 and 2.3 mbgl, corresponding to approximate elevations of ‐0.3 to
0.05 mAHD. Underlaying the fill layer were natural sands starting with a relative density of medium dense
to dense at depth of silty sand to 3.3 m depth (approx. 0.9 mAHD), then a layer of medium dense, dense
to very dense (indurated) sands from between 4.8 to 5.4 m depth (approx. ‐2.9 to ‐3.1) and continuing
until the termination depth of 6.0 mbgl in all boreholes.
As part of the Preliminary Geotechnical Investigation (2020) and Additional Geotechnical Investigation
(2021), Acid Sulfate Soil (ASS) samples were collected at 0.25m intervals in BH1 to BH4 to 4.0 m depth. A
total of 64 samples were collected for ASS screening and 11 samples were selected for further analysis
by the Chromium Reducible Sulfur suite (CRS).
ADG notes that the testing was generally in accordance with the National Acid Sulfate Soil guidance
documents in terms of a minimum 4 test locations and to approximately 1.0 m below proposed extent of
excavation and dewatering with ASS testing to 4.0 m depth. DP reports that within this depth profile both
the existing sand fill and natural silty sand are considered to be mildly acidic, with both the fill layer and
natural sands considered to contain low level PASS requiring liming at minimal rates of 2 kg/tonne.
3.1.2 Groundwater
Groundwater seepage was recorded at between 1.65 to 2.35 mbgl (equating to approximate
groundwater elevations of 0.25 to 0.05 mAHD), during preliminary and follow‐up geotechnical works
(drilling) on the site by Douglas Partners in September 2020 and December 2021. Douglas Partners also
undertook a follow‐up standing water level gauging of 1.7 mbgl (equating to groundwater elevation of
0.2 mAHD). (Douglas Partners, 2020 & 2022).
It should be noted however, that groundwater depths and ground moisture conditions are affected by
weather and climatic conditions, tidal variations, surface and subsurface drainage/permeability
conditions, and human influence and will therefore vary with time. Groundwater levels are expected to
be similar to the water level in the canal at the rear of the site, albeit somewhat a dampened response
to tidal variations.
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As part of the Additional Geotechnical Investigation, DP installed a PVC standpipe in BH3, and undertook
sampling and analysis of groundwater on 18 January 2022 generally consistent with the National Acid
Sulfate Soil guidance documents. Sample analysis was performed by ALS Environmental laboratory, with
a summary of the analytical data provided below.
Table 2 Summary of key analytical groundwater data (sourced from DP 2022)
Parameter/Analyte BH3/MW3
Physico‐chemical
pH (pH units) 7.76
Electrical conductivity (µS/cm) 1,200
Total alkalinity (mg/L) 89
Dissolved metals (µg/L)
Aluminium 20
Arsenic <1
Cadmium <0.1
Chromium <1
Copper 2
Iron <50
Lead <1
Nickel 1
Zinc 8
Total metals (µg/L)
Aluminium 128,000
Iron 75,100
Other (mg/L)
Calcium 127
Magnesium 19
Sodium 106
Potassium 7
Chloride 93
Sulfate 355
Chloride: Sulfate ratio 0.26
Table notes:
<LOR = less than the limit of reporting
In summary, groundwater beneath the site is considered to be brackish and slightly basic pH, with low
alkalinity and buffering capacity. The soluble chloride to sulfate ratio is less than 4, which indicates that
where ASS are present underlying the site, they have been previously oxidised and sulfate released. No
exceedances of the relevant groundwater investigation levels (GILs; NEMP (2013)) or Noosa River
environmental values and water quality objectives (DERM 2010) were reported for any dissolved metals.
High levels of total iron and total aluminium were reported however there is currently no relevant
criterion for total iron or aluminium in marine waters. The high total iron and total aluminium
concentrations, along with low to non‐detectable concentrations of dissolved aluminium and iron,
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indicates that these metals are present in insoluble form and should generally be readily settled with
sufficient retention time and/or readily removed via specialised fine media filtration.
3.2 Groundwater quality
ADG is of the opinion that localised monitoring well data can often be misleading and does not always
accurately represent the properties of the groundwater that will be extracted and treated from the entire
site and local surrounds during dewatering. Therefore, based on numerous groundwater investigations
and dewatering monitoring projects that have been undertaken by ADG throughout the Noosa Coast
Region in recent years, our understanding of the groundwater quality in the region is provided below:
Groundwater is generally mildly acidic to neutral, with pH levels ranging from approximately 5.5
to 6.5 and electrical conductivity ranging from brackish to saline between 2,000 µS/cm to
48,000 µS/cm. Groundwater pH has the potential to reduce (become more acidic) following
oxidisation of PASS as dewatering progresses, particularly if re‐wetting of the soils occurs.
Dissolved oxygen levels in static groundwater typically range from approximately 35 – 40 %
saturation.
The groundwater associated with indurated sand strata is moderately to highly turbid as a result
of staining and organic content.
Concentrations of dissolved metals are typically below the available marine water trigger values
(MWTV’s) provided in ANZECC/ARMCANZ (2000) for the receiving waters, however elevated
levels of aluminium and particularly iron are expected in the untreated groundwater and have
the potential to increase following oxidisation of PASS as dewatering progresses or as a result of
existing acidic groundwater conditions.
Given the location and previous use of the site, groundwater impacts resulting from site
contamination are not anticipated.
A groundwater investigation will be undertaken at the commencement of dewatering as described in
Section 6.5.2 of this report. This assessment will be representative of the groundwater being extracted
and treated from the entire site, as opposed to localised monitoring well data which is often misleading.
Based on previous experience with dewatering in the area, ADG expects the groundwater to require
treatment to increase pH and dissolved oxygen levels, as well as reduce turbidity, suspended sediments
and dissolved metal concentrations prior to being discharged to the Noosa River.
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4 Water quality objectives
4.1 Receiving environment
It is proposed to discharge extracted groundwater directly over the revetment wall into the Noosa River
adjacent to site. The exact location of the receiving waters/environment will be confirmed on
commencement of dewatering.
The receiving environment in this location identifies as a moderately disturbed, middle estuary
environment. The following section establishes water quality objectives (WQOs) to ensure that the
environmental values of the receiving waters are protected and maintained.
4.2 Development of water quality objectives
WQOs have been developed to support and protect the designated environmental values (EVs) for the
receiving environment. The WQOs are based on a moderately disturbed level of protection for enclosed
coastal/lower estuaries. The WQOs have been developed with reference to the following guideline
documents:
Australian and New Zealand Guidelines for Fresh and Marine Water Quality 2018. (ANZG 2018)
The selected trigger values apply to moderately disturbed systems to provide a 95% level of
species protection for marine waters.
Environmental Protection (Water & Wetland Biodiversity) Policy 2019. 2019. Noosa River
environmental values and water quality objectives. DES.
Environmental Protection (Water) Policy 2009, Noosa River environmental values and water
quality objectives. 2010. DERM.
Queensland Water Quality Guidelines, Version 3, September 2009. 2013. DEHP.
The Australian and New Zealand Guidelines for Fresh and Marine Water Quality by the Australian and
New Zealand Environment and Conservation Council and Agriculture and Resource Management Council
of Australia and New Zealand (ANZECC/ARMCANZ, 2000), has undergone review, with the publication of
the 2018 version. The revised Australian and New Zealand Guidelines for Fresh and Marine Water Quality
2018 is a joint initiative between the Australian and New Zealand Governments and Australian state and
territory governments (ANZG, 2018) and supersedes the ANZECC/ARMCANZ 2000 publication. Where
ANZECC/ARMCANZ (2000) is referenced, the relevant sections are still relevant and consistent with the
updated ANZG 2018 publication, as referenced in the ANZG 2018 publication.
The Queensland Water Quality Guidelines 2009 (DEHP, 2013) was made pursuant to the provisions of the
Environmental Protection (Water) Policy 1999 (the EPP(Water)), which is a subordinate legislation under
the Environmental Protection Act 1994 and was developed as the State response to the
ANZECC/ARMCANZ (2000) Guidelines. The EPP(Water) provides a framework for:
Identifying environmental values for Queensland waters, and deciding the water quality
objectives to protect or enhance those environmental values.
Including the identified environmental values and water quality objectives under Schedule 1 of
the EPP (Water).
WQOs are long term goals for surface water quality management. They are indicators established for
receiving waters to support and protect the designated Environmental Values (EVs) for those waters.
DERM (2010) describes that for slightly to moderately disturbed waters, the guideline values should be
compared with the median of values at a test site, whilst ANZG (2018) stresses that the aquatic ecosystem
guideline values are triggers to further action, are inherently conservative, and that the response to non‐
compliance should match the magnitude and impacts (if any) of the exceedance.
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Regardless of the WQOs adopted in this DMP, the General Environmental Duty set out in the EP Act is
paramount, which requires that “a person must not carry out an activity that causes or is likely to cause
environmental harm unless the person takes all reasonable and practicable measures to prevent or
minimise the harm”.
4.3 Proposed water quality objectives
The proposed water quality objectives that have been developed for the discharge of extracted
groundwater from the site are provided in the Tables below. All water discharged from the site must
comply with the discharge criteria provided in Table 3. In addition, the receiving water quality within a
20 m radius of the discharge point entry to the receiving water shall comply with the receiving water
criteria provided in Table 4. Receiving waters data will be assessed against background monitoring data
if non‐compliant results are obtained at the receiving waters monitoring location.
Table 3 Discharge criteria
Parameter Criteria
Physico‐chemical
pH (pH units) 6.5 – 8.51
Dissolved oxygen (% saturation) >802
Suspended solids (mg/L) ≤501,2
Turbidity (NTU) ≤502
Litter None visible
Totals metals (µg/L)
Aluminium No ANZG criteria / 2003
Iron No ANZG criteria / 3003
Table notes:
1. QWQG 2009 (2013) Refer to Table 8.2.1. Summary of design objectives for management of stormwater quality and flow –
construction phase of development in Queensland.
2. Typical discharge criteria recognised throughout Queensland & NSW.
3. Criteria subject to RAP21/0020 Condition 26 in Development Application (DA) notice by Noosa Shire Council.
Table 4 Receiving waters criteria
Parameter Criteria
Physico‐chemical
pH (pH units) 7.8 – 8.31
Dissolved oxygen (% saturation) 85 – 1051
Suspended solids (mg/L) <201
Turbidity (NTU) <81
Dissolved metals (µg/L)
Aluminium No relevant ANZG criteria available
Arsenic 2.32*
Cadmium 5.52
Chromium 4.42
Copper 1.32
Iron No relevant ANZG criteria available
Lead 4.42
Nickel 702
Zinc 152
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Parameter Criteria
Mercury 0.42
Totals metals (µg/L)
Aluminium No ANZG criteria / 2003
Iron No ANZG criteria / 3003
Table notes:
1. DERM (2010). Noosa River environmental values and water quality objectives (middle estuary waters).
2. ANZG (2018). Supersedes ANZECC/ARMCANZ (2000) ‐ Marine water trigger values for 95% species protection.
3. Criteria subject to RAP21/0020 Condition 26 in Development Approval (DA) notice by Noosa Shire Council.
* = Insufficient data to derive a reliable trigger value. Low reliability value adopted (refer ANZECC/ARMCANZ (2000) Section
8.3.7.
Although ADG has not been provided a copy of the DA notice and conditions for the proposed
development, based on previous dewatering projects in the Sunshine/Noosa Coast Region it is expected
that total iron and aluminium concentrations as listed in Table 4 (above) are likely to be conditioned by
Noosa Shire Council for compliance. It should be noted that these concentrations are considered to be
onerous with respect to the risk‐based (worst‐case) bioavailable trigger value criteria contained in ANZG
2018 & ANZECC/ARMCANZ (2000) for marine water (moderately disturbed) 95% species protection, and
are likely to be difficult to achieve given the groundwater conditions encountered in the locality on
previous dewatering projects on the Sunshine/Noosa Coast.
Prior to discharge to the stormwater system or any waterway, discharges are to be tested to meet the
requirements of the ANZG 2018 & ANZECC/ARMCANZ (2000) Guidelines for Fresh and Marine Water
Quality. There is currently no chemical toxicant trigger value criteria available for total or dissolved (i.e.
bioavailable) concentrations of aluminium or iron for marine or estuarine waters under the Australian
and New Zealand Guidelines for Fresh and Marine Water Quality Guidelines (ANZG 2018 &
ANZECC/ARMCANZ 2000 – i.e. ANZECC Guidelines) or the Guidelines for Managing Risks in Recreational
Waters (NHMRC 2008), with regards to managing environmental impacts to the waterway.
In addition, Section 5 (Guidelines for recreational water quality and aesthetics) of the ANZECC/ARMCANZ
(2000) Guidelines (per section 5.2 thereof) was superseded by the Guidelines for Managing Risks in
Recreational Water in 2008 (NHMRC, 2008). Therefore, a reference to the ANZECC/ARMCANZ (2000)
Guidelines is by association and extension a reference to the current 2008 NHMRC Guidelines. The 2008
NHMRC Guidelines contain no criteria for aluminium, and only includes an aesthetic criterion for iron –
noting this is an aesthetic criterion derived from the Australian Drinking Water Guidelines on the basis of
ingesting 2L of the recreational water solution per day. ANZECC/ARMCANZ (2000) Section 5.2.3.3, notes
that as a general guideline, under Toxic Chemicals, ‘Higher concentrations of toxicants may be tolerated
occasionally if it assumed that no person will ingest more than a maximum of 100 mL water during a
normal swimming session (NHMRC 1990) compared with 2L/d for potable water’, and Section 3.1.1.3,
under Risk based approach of the guidelines, ‘The guideline trigger values are based on bioavailable
concentrations, and hence are relatively conservative when compared with total concentrations in the
field, so the use of the decision frameworks will increase guideline concentrations in most cases’.
Therefore, any chemical toxicant trigger values would require reassessment and likely increase upwards
of any ANZG 2018 &/or ANZECC/ARMCANZ (2000) Guideline trigger values due to the slightly to
moderately disturbed nature (and thereby reduced sensitivity) of the receiving waters.
In conditioning more onerous criteria, rather than the available marine chemical toxicant trigger value
criteria contained within the ANZG/ANZECC Guidelines, an unachievable constraint may be placed on the
development. This DMP has allowed for contingency measures to be incorporated into the treatment
and discharge system if required, including silt curtains to be installed within the receiving waterway
surrounding the discharge location, or further onsite treatment measures such as filtration, to prevent
and/or minimise as far as reasonably practicable the potential for release of suspended solid loads into
the broader receiving waterway.
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5 Dewatering methodology
5.1 Basement excavation and shoring
It is understood that the excavation/basement perimeter will be stabilised along the perimeter of the
basement excavations using secant piles (i.e. soldier pile wall with grout injection between piles socketed
into dense indurated sands and deeper underlying strata such as low permeability marine clays; 'cut off’
wall). Excavations to facilitate the construction of the basement will extend to approximately 3.1 m below
ground level, which corresponds to a maximum elevation of ‐0.8 m AHD. Localised deeper excavations
may be required for construction of other structural elements (i.e. footings & pile caps).
All excavated spoil from within the excavation footprint will be appropriately neutralised with lime and
validated in accordance with recommendations by DP in the Preliminary and Additional Geotechnical
Investigation Reports (DP, 2020 & 2022).
5.2 Groundwater extraction
Dewatering will be undertaken using a series of 6.0 m length, 40 mm diameter PVC spears installed to
below maximum excavation depth at 1.5 m intervals around only the internal perimeter of the basement
excavation. Dewatering only on the internal face of the secant pile (cut off) shoring wall will minimise the
extent of dewatering to predominantly or completely within the site boundaries, and minimise
dewatering flow rates and thereby also minimise the extent of the estimated cone of depression of the
groundwater table outside of the basement excavation footprint. Potential or actual acid sulfate soils
outside of the excavation footprint are therefore not anticipated to be impacted by dewatering on the
internal face of the secant pile (cut off) shoring system. Alternatively, or in addition to the spear system,
a sump and pump system may be employed where seepage rates are lower than estimated.
The basement excavation must be dewatered to a minimum of approximately 1.0 m below the deepest
point of excavation to allow construction to be undertaken in dry conditions. The water table is therefore
expected to be lowered by minimum of approximately 1.8 m to around ‐1.85 m AHD. This limited depth
of groundwater abstraction on the internal face only of the secant pile (cut off) shoring wall will minimise
total groundwater extraction and minimise the estimated cone of depression in the standing
groundwater table, generally to within the secant pile (cut off) wall only.
It is proposed that the development will include a ‘tanked’ basement to prevent the requirement for a
permanent dewatering facility at the site. Similarly, no permanent groundwater dewatering is proposed
or likely to occur as a result of the development, with all services and pipework proposed to be situated
above standing groundwater elevations (that is, at elevations above 0.25 mAHD) and subject to the
nominated hold points at Section 5.7. Where any deviation is proposed from this arrangement, all
pipework within the saturated zone, that outlets direct to waterways must be fitted with buried
headstocks at suitable intervals to prevent ongoing dewatering of groundwater along pipework bedding
in accordance with Development Approval RAP2020/0020 Condition 29.
5.3 Extraction/discharge rates and volume
5.3.1 Dewatering extraction calculation based on subsurface soil profile
The dewatering extraction rate, area of influence and cone of depression has been estimated to be
minimal due to the proposed dewatering only on the internal face of the secant pile (cut off) shoring wall,
which will minimise the extent of dewatering to predominantly or completely within the site boundaries,
and minimise dewatering flow rates and thereby also avoid and minimise the extent of the estimated
cone of depression of the groundwater table outside of the basement excavation footprint.
Based on the dewatering methodology proposed (internal face of secant shoring wall only) and extensive
previous experience in similar ground conditions, a groundwater flow rate of approximately 3 to 5 L/sec
or 180 to 300 L/min or 10,800 to 18,000 L/hr has been predicted for the development, with the estimated
cone of depression radius to be limited to within 1 m of the secant pile shoring wall. Flow rates are
predicted to be highest during initial drawdown of the groundwater table within the basement excavation
footprint, and reducing to approximately 3 L/sec following establishment of the cone of depression within
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the excavation. Flow rates may fluctuate due to tidal variations, generally approximately ± 0.5 m, and will
also be influenced by rainfall and surface water collection within the basement excavation footprint
noting the underlying predominantly sand profile encountered during geotechnical investigations.
Regardless of the contractor employed, groundwater treatment systems should be installed with
capability for treating flow rates of up to 8 to 10 L/sec, as a contingency against higher than anticipated
flow rates exceeding the estimated 3 to 5 L/sec as a result of varying ground conditions across the extent
of excavation.
5.4 Dewatering duration
Dewatering will be necessary throughout the basement construction phase, which is expected to require
dewatering for approximately 10 to 12 weeks. To minimise the potential impacts during construction of
short‐term dewatering, periods of active dewatering will be minimised as much as possible. However,
ADG notes that once active dewatering has commenced, dewatering will not be able to be ceased until
both: a) the basement hydrostatic uplift forces have been compensated to the satisfaction of the
consulting RPEQ engineer; and b) potential hydraulic loading on the external face of the secant pile
shoring system has been compensated to the satisfaction of the consulting RPEQ engineer and shoring
contractor.
5.5 Groundwater drawdown
Groundwater drawdown caused by dewatering has the potential to create settlement in unconsolidated
sediments and loose sands. Any such settlement is proposed to be minimised via the revised shoring
approach of using a full secant pile (cut off) shoring wall around the basement excavation and only
dewatering on the internal face of the secant pile wall. It is noted that dilapidation reports for surrounding
structures and services have been undertaken which were not supplied to ADG for the purposes of
preparing this DMP, and are to be provided to Council separately from this DMP.
Groundwater drawdown may also oxidise potential acid sulfate soils within the cone of depression,
subsequently producing acidic groundwater conditions and mobilising heavy metals. Monitoring of the
extracted untreated groundwater will be undertaken to detect potential in‐situ oxidation, as required
and at the frequencies stated in Section 6.5.2. Groundwater monitoring bores for groundwater level
gauging external to the excavation footprint are unable to be established and monitored prior to and
during construction on the site (as per Development Approval RAP2020/0020 Conditions 27 and 28) due
to the secant pile (cut off) walls to be located in close proximity to property boundaries and therefore
monitoring bores cannot be installed due to limited space (refer SCG Consulting Engineers letter dated
02/02/22, ref. 31073(L2)).
A plan showing the proposed shoring and dewatering system and estimated cone of depression contours
is provided at Appendix C.
5.6 Groundwater treatment
All extracted groundwater will be treated on‐site using available technologies prior to discharge to the
stormwater network. The following treatment measures will be adopted, and will be installed and
operational prior to the commencement of dewatering:
1. A groundwater pH buffering treatment system (primary treatment)
2. A sedimentation tank to provide additional residence time and sedimentation (secondary
treatment).
3. Installation of fine media filtration to retain suspended sediments and/or heavy metals (tertiary
treatment), if required.
Details of the treatment systems and methodologies are provided in Section 6 of this report.
Note: Consideration should be taken, regarding placement of treatment gear on site to enable easy
cleaning and maintenance throughout the dewatering phase for the project. Consider the potential
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requirement for regular de‐sludging of sedimentation tank/s to suitable area onsite, if available (cost
minimisation).
5.7 Nominated Hold Points
In accordance with Development Approval RAP2020/0020 Condition 22(e), nominated hold points to be
enacted during construction have been proposed to facilitate for certification by the suitably qualified
person experienced with Acid Sulfate Soils, as well as Council Development Engineer to ensure all possible
avenues for continual dewatering below permanent groundwater level, including around pipework
bedding that outlet to waterways, are appropriately sealed. The nominated hold points regarding
dewatering for this project are:
1. Prior to commencement of dewatering/initial pump out
2. At finished excavation level, prior to blinding layer application
3. External to basement service installation trench opening/s prior to backfilling.
The above nominated hold points are subject to confirmation by the consulting engineer, and liaison with
council representatives and the Site Manager.
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6 Water quality management
6.1 Responsibility
The Site Manager is ultimately responsible for implementing the water quality management procedures
described in this DMP.
6.2 Operational policy
To prevent impacts on the receiving waters by effectively treating all extracted groundwater prior to
discharge from the site.
6.3 Performance criteria
The performance criteria for the discharge of extracted groundwater are the water quality objectives
provided in Table 3 and Table 4 in Section 4 of this report. Both the discharge and receiving waters (within
a 20 m radius of the stormwater discharge point) will be assessed against the WQOs to ensure that the
environmental values of the waterway are maintained. Receiving waters data will also be assessed
against background monitoring data if non‐compliant results are obtained at the receiving waters
monitoring location.
6.4 Implementation strategy
All extracted groundwater will be treated on‐site using available technologies prior to discharge to the
stormwater network. The treatment system described in Section 6.4.1 will be adopted, installed and
operational prior to the commencement of dewatering. The proposed secant pile shoring wall and
location of proposed dewatering treatment equipment contemplated under this DMP is provided in
Appendix C.
6.4.1 Groundwater treatment systems
Subject to final appointment of shoring and dewatering contractors (who all generally have different
treatment systems), the following treatment systems are generally proposed for dewatered groundwater
treatment prior to discharge. Regardless of the contractor employed, groundwater treatment systems
should be installed with capability for treating flow rates of up to 8 to 10 L/sec, as a contingency against
higher than anticipated flow rates exceeding the estimated 3 to 5 L/sec as a result of varying ground
conditions across the extent of excavation.
Primary treatment
A groundwater treatment system will be installed to provide primary treatment of the extracted
groundwater. The system will provide the following capabilities:
1. A baffled treatment tank with 5 kL minimum capacity
2. Automated in‐line chemical dosing systems for the addition of buffering solutions and coagulants
3. A filtration system to reduce fine particulates (if required)
4. Emergency response alarms for non‐routine situations.
Based on the estimated extraction rate, this system will provide approximately sixteen to twenty‐seven
minutes contact time during the initial chemical dosing, prior to secondary treatment using a
sedimentation tank. Primary treatment tank will be vertically stacked on the secondary treatment tank
wherever practicable to minimise site area required for groundwater treatment equipment.
Secondary treatment
A 23 kL sedimentation tank will be utilised to provide the necessary residence time for secondary
treatment of the groundwater prior to discharge to the stormwater system. Based on the estimated
groundwater extraction rate of approximately 3 to 5 L/sec (or 180 to 300 L/min or 10,800 to 18,000 L/hr)
from Section 5.3.1 of this report, one sedimentation tank will provide between approximately seventy‐
six and one‐hundred‐and‐twenty‐seven minutes retention time following primary treatment of the
extracted groundwater. This is considered to be sufficient secondary settling / retention time based on
extensive prior experience on other sites in similar ground conditions.
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Tertiary treatment – may be required following initial testing of extracted groundwater.
A filtration treatment system with specialised fine filtration media and chlorine dosing will be utilised to
provide the required heavy metal removal (specifically for total and dissolved iron) where not
precipitated and retained within the sedimentation tank/s (secondary treatment). This treatment system
will provide tertiary treatment of the groundwater prior to offsite discharge. This type of fine media
filtration treatment system is a forced‐flow system under pressure, and generally capable of treating flow
rates of up to 20 L/sec per filtration unit (therefore residence time is inconsequential to treatment quality
achieved).
Tertiary treatment will only be required if the required water quality is unable to be achieved following
primary and secondary stages of treatment. Subject to the results of field and laboratory testing during
the pre‐discharge monitoring event.
6.4.2 Dewatering strategy
The Site Manager, Dewatering Contractor and ADG Consulting must formulate a dewatering strategy to
ensure that the dewatering treatment system is sufficient to meet the requirements of the project and
that the necessary equipment can be accommodated within the site prior to the commencement of
dewatering. Where the construction of the proposed development requires occupation of the road
reserve (verge area and/or road formation) for either short term or long term, a road reserve permit must
be obtained from Council prior to any occupation of the road reserve, in accordance with RAP21/0020
Part 5 Condition 9.
6.4.3 Initial pump‐out
Prior to discharge of any extracted groundwater to the canal system, the following pre‐dewatering
procedure will be undertaken:
1. The basement area will be excavated down to the standing groundwater level.
2. The initial dewatering discharge will be directed (via the treatment systems) into the excavation and
allowed to infiltrate/recharge the aquifer. This process will provide initial clarification of the extracted
groundwater as disturbed sediment loads are typically reduced following the initial pump‐out.
3. Samples of the treated groundwater will be recovered and analysed for the parameters detailed in
Table 3 and Table 4.
4. The extracted groundwater will be directed into the canal system following confirmation that the
water quality complies with the discharge criteria.
6.5 Monitoring
6.5.1 Visual monitoring
Visual inspections of the site and dewatering equipment shall be undertaken daily by the Site Manager
to identify the following:
Quantity of chemical product within the dosing system
Effective operation of all dewatering treatment equipment
Short circuiting of water around baffles and filter media in sediment tanks, where required to
be installed.
Visible hydrocarbon sheens and odours
Green blue or extremely clear water indicating high levels of dissolved aluminium.
6.5.2 Water quality monitoring
Water quality monitoring will be undertaken for the duration of dewatering activities at the site by a
suitably qualified and independent person. The monitoring will include analysis of the extracted
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groundwater, treated discharge water and off‐site monitoring in the receiving waters (in the mixing zone
within a 20 m radius of the discharge point). The exact location within the receiving waterway (Noosa
River) is to be confirmed, however it is anticipated to be directly north of the site. Background water
quality monitoring of field parameters will also be conducted during each sampling event, if applicable.
Background samples will be recovered from the river, either upstream or downstream from the receiving
water location (tide dependant).
The proposed monitoring locations are shown in Figure 1, Appendix A are a subject to confirmation
following mobilisation of dewatering gear to site.
Monitoring will be undertaken at the following frequencies:
Daily monitoring of field parameters (pH, electrical conductivity, dissolved oxygen, temperature
and turbidity) in the treated discharge water and pH of the untreated extracted groundwater (to
determine potential acidification). Daily monitoring will be undertaken by a suitably trained site
employee under the supervision of the Site Manager.
Weekly monitoring of field parameters (pH, electrical conductivity, dissolved oxygen,
temperature and turbidity) in the untreated extracted groundwater, treated discharge water,
receiving waters and background waters by ADG Consulting.
Weekly laboratory analysis of treated discharge water and receiving waters for suspended solids
and dissolved 0.45µm filterable metals (aluminium, arsenic, cadmium, chromium, copper, iron,
lead, nickel, zinc and mercury). Total aluminium and iron will also be analysed for, if required.
Pre‐discharge/initial monitoring of field parameters (pH, electrical conductivity, dissolved
oxygen and oxidation‐reduction potential) in the extracted groundwater (prior to treatment) to
assess changes in groundwater chemistry associated with PASS oxidation.
Pre‐discharge/initial laboratory analysis of extracted groundwater (prior to treatment) for
suspended solids, dissolved 0.45µm filterable metals (aluminium, arsenic, cadmium, chromium,
copper, iron, lead, nickel, zinc and mercury) and for soluble sulfate and chloride to assess
changes in groundwater chemistry associated with PASS oxidation. Total aluminium and iron will
also be analysed for, if required.
Laboratory analysis of untreated groundwater would also be performed periodically (monthly)
if changes in untreated groundwater pH levels are detected that may indicate local acidification,
and to determine any changes in local groundwaters that may require further investigation of
potential environmental impacts.
All samples will be recovered by a suitably qualified Environmental Scientist and submitted to a National
Association of Testing Authorities (NATA) accredited laboratory for analysis.
6.5.3 Monitoring responsibilities
The persons responsible for undertaking the compliance monitoring described in Section 6.5.2 above are
shown in Table 5.
Table 5 Monitoring responsibilities
Activity Frequency Responsibility Person
Monitoring of field parameters in discharge water
Daily Site Manager Site Manager
and untreated extracted groundwater
Monitoring of field parameters in untreated
Environmental
extracted groundwater, discharge water, Weekly ADG Consulting
Consultant
receiving waters and background waters
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Laboratory analysis of samples recovered from Environmental
Weekly ADG Consulting
discharge water and receiving waters Consultant
Monitoring of field parameters in extracted Environmental
Weekly ADG Consulting
groundwater (pre‐treated) Consultant
Laboratory analysis of samples recovered from Initially, then as Environmental
ADG Consulting
extracted groundwater (pre‐treated) required Consultant
6.6 Maintenance
The groundwater treatment systems must be regularly maintained. Maintenance must include:
Regular cleaning and or replacement of the filters within the filtration unit, where required to
be installed.
Regular removal of sediment from the sedimentation tank. The sediment must be either
returned to the excavation pit for dewatering and bulking out with excavated material, or
removed from the site by a licensed liquid waste contractor.
Regular check of the dosing system and top‐up of buffering solutions and flocculants.
6.7 Reporting
Dewatering management procedures and monitoring results will be reviewed by ADG Consulting weekly
to ensure that the treatment procedures are effective, and that the receiving waters are not being
impacted by the extracted groundwater being discharged.
The following reporting procedures will be adopted:
A summary report will be prepared upon completion of the initial pre‐discharge monitoring. The
report will be submitted to the Site Manager, Dewatering Contractor, and NSC upon request.
Weekly interim reports will be prepared upon receipt of laboratory data for each round of
ongoing compliance monitoring. The interim reports will display all data obtained during the
previous monitoring event, and provide comments and recommendations based on the results.
A dewatering compliance report will be prepared on completion of the project (upon request).
The above reports will be prepared by ADG Consulting and provided to the Site Manager and Dewatering
Contractor as they become available. The reports will include all water quality results and comparison to
the WQOs, corrective actions and recommendations made to the Site Manager and Dewatering
Contractor during the monitoring period.
The Site Manager must keep records of complaints, volumes of chemicals used, and treatment methods
employed. These records must be available on‐site at all times and submitted to NSC by the Site Manager
upon request.
6.8 Contingencies
If water quality monitoring indicates ongoing exceedances of the performance criteria, and the water
quality objectives for the receiving waters cannot be met, then corrective actions will be adopted as
necessary. Possible contingencies may include one or more of the following:
Installation of additional sedimentation tanks to provide increased residence time and assist
with the retention of precipitated iron hydroxides, other heavy metals and/or suspended
sediments.
Installation of additional flocculant and/or coagulant dosing systems to assist in precipitation of
suspended sediments and/or heavy metals.
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Installation of activated carbon filtration or other fine media filtration to retain suspended
sediments and/or heavy metals.
Install a floating sediment curtain/s around the stormwater termination point in the receiving
waterway to prevent unsightly plumes and contain sediment and/or heavy metals for periodic
removal (subject to approval by Noose Shire Council).
Preventive and corrective actions shall be taken in the event that groundwater monitoring
observations indicate that unexpected groundwater contamination has been encountered
during dewatering. The most appropriate action(s) shall be dependent on the stage of
construction and risk of adverse impacts to groundwater users and the receiving environment.
Any modification to the dewatering system and pumping rates shall be in consultation with a
suitably qualified scientist/geotechnical/engineer.
Following heavy rainfall all ponded surfaces waters are to meet discharge criteria (Table 3) prior
to offsite discharge. Where discharge criteria not met, Site Manager to obtain approval from
Dewatering Contractor regarding treating surface waters with treatment gear before offsite
discharge.
Pumping systems and shoring works to be maintained in fit for purpose state by Dewatering
Contractor and/or shoring contractor. In the event that dewatering equipment has failed and is
likely to cause a significant impact on the environment, or surrounding properties (i.e. flooding)
the Dewatering Contractor is to be contacted immediately. The Principal Contractor, in
consultation with the Dewatering Contractor shall be responsible in rectifying the failure in a
practicable time frame to minimise potential impacts. Equipment, spare parts, materials and
tools necessary to manage aspects of the system/s which present a high risk of significant
impacts in the event of failure (if any) shall be readily available.
Construction vibrations could potentially cause settlement in the loose upper level sands,
thereby damaging nearby structures founded in these strata. Prior to commencement of
construction on site (including staged works), it is recommended that a detailed dilapidation
survey be undertaken to establish the condition of all existing adjacent structures, roads and
services.
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7 Noise & odour management
7.1 Responsibility
The Project Manager is responsible for ensuring the appropriate management of noise and odour during
dewatering operations.
7.2 Operational policy
To minimise noise and odour emissions generated from the site during dewatering.
7.3 Performance criteria
The appropriate criteria to measure the performance of dewatering management at the site are provided
below.
1. No noise or odour related complaints received from neighbouring residents or the community.
2. No degradation of air quality due to fumes or odours emanating from the dewatering process.
7.4 Implementation strategy
Noise and odour emissions will be managed as described in the following sections.
7.4.1 Noise
All dewatering equipment must be operated appropriately and maintained in good working order. All
dewatering systems and plant must be fitted with the appropriate noise reduction equipment to comply
with the performance criteria. Non‐complying dewatering plant will be replaced or repaired as necessary.
It is proposed to employ noise mitigation strategies including use of electric pumps and dewatering
systems rather than diesel powered equipment. Noise attenuation blankets and screens will be installed
around noise generating dewatering pumps and equipment where practicable. Noise monitoring
equipment (unattended will be installed by the site manager prior to commencement and monitored for
the duration of dewatering.
7.4.2 Odour
All dewatering plant must be fitted with the appropriate emission reduction devices. Where practicable,
all dewatering plant will be sealed to prevent the release of odours to the atmosphere. Fine mist odour
control sprays will be applied to reduce offensive odours if complaints are received from neighbouring
residents.
7.5 Monitoring
An inspection of the site and dewatering equipment shall be undertaken daily by the Site Manager to
identify the following:
Excessive noise being generated by the dewatering systems and plant; and
Strong or offensive odours being generated by the dewatering equipment and/or extracted
groundwater.
Noise monitoring equipment (unattended, continuous logging) will be installed by the Site Manager prior
to commencement and monitored for the duration of dewatering. The Environmental Protection (Noise)
Policy 2019 (EPP(Noise)) identifies specific acoustic quality objectives (noise criteria) to assist in
preventing significant impacts on noise sensitive receptors and as a guide to long‐term acoustic quality
for sensitive receptors. The primary EPP(Noise) criteria relevant to this investigation is outside a dwelling
(i.e. adjacent dwellings), which should not have noise at levels in the daytime or evenings greater than
50dB(A) LAeq,adj,1hr. This means that noise levels in the receiving environment outside of nearby
dwellings (i.e. on balconies) should not exceed an equivalent sound energy as would be received from a
one hour continuous sound of 50 decibels on the A‐weighted scale (adjusted for tonal character
perceptible by the human ear).
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While this report has not been generated for the purpose of assessing compliance with the requirements
of workplace health and safety legislation, it is noted that a person conducting a business or undertaking
must ensure that workers are not exposed to noise that exceeds the exposure standard for noise. The
exposure standard for noise is defined in the Work Health & Safety Regulation 2011 (QLD) as LAeq,8h of
85 dB(A) or an LC,peak of 140 dB(C). As such, it is considered appropriate to adopt these exposure
standards to assess average and peak noise generated at the site with the potential to affect exposure
levels of nearby sensitive receptors (noting there will be some attenuation between source and receptors
and actual noise experienced by receptors would need to be measured at the receptor location).
7.6 Reporting
The Site Manager must keep records of complaints, monitoring records (including continuous noise
monitoring data), and corrective and preventive actions/methods employed for noise abatement. These
records must be available on‐site at all times and submitted to NSC by the Site Manager upon request.
7.7 Contingencies
If noise levels consistently exceed the performance criteria, temporary acoustic barriers will be
constructed around the offending dewatering systems and plant. Odour control sprays will be applied as
necessary to mask odour emissions if complaints are received from neighbouring residents. This may
include the direct injection of deodorisers to the groundwater treatment system.
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8 Limitations
ADG Consulting Pty Ltd has prepared this report for Chris Clout Design and Michelle and Franco
DePasquale in accordance with the agreed scope of work. The services performed by ADG have been
conducted in a manner consistent with the normal level of care and expertise exercised by members of
the environmental consulting profession. No other warranty or guarantee, expressed or implied, is made
as to the professional advice included in this report.
This report is solely for the use of Chris Clout Design and Michelle and Franco DePasquale and ADG
accepts no responsibility for the use of any part of this report for any other purpose or by third parties,
as it may not contain sufficient information for the purposes of other parties or users. This report must
only be presented in full, and may not be used for any other objective, except where prior written
approval is obtained from ADG. This report does not comment on legal obligations, as legal advice can
only be given by qualified legal practitioners.
The information contained in this report is provided to minimise potential impacts on the receiving
environment, however implementation of the described management procedures does not guarantee
that the objectives will be achieved.
The information contained in this report is considered to be accurate at the date of issue. Subsurface
conditions, including contaminant concentrations can change in space and time, either through natural
processes or by the accidental or intentional addition of contaminants to a site. Where conditions
encountered subsequently at the site are significantly different from those reported herein, ADG must
be notified and be provided the opportunity to review the conclusions and recommendations of this
report.
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9 References
ANZG 2018. Australian and New Zealand Guidelines for Fresh and Marine Water Quality. Australian and
New Zealand Governments and Australian state and territory governments, Canberra ACT, Australia.
ANZECC/ARMCANZ. 2000. Australian and New Zealand Guidelines for Fresh and Marine Water Quality.
Australian and New Zealand Environment and Conservation Council and Agriculture and Resource
Management Council of Australia and New Zealand.
DES. 2019. Environmental Protection (Water & Wetland Biodiversity) Policy 2019. Department of
Environment and Science, Queensland Government. Brisbane, Queensland, Australia.
DEHP. 2013. Queensland Water Quality Guidelines 2009, Version 3. Department of Environment and
Heritage Protection. Brisbane, Queensland, Australia.
DERM. 2010. Noosa River environmental values and water quality objectives. Department of Environment
and Resource Management (DERM), Queensland Government.
DES. 2018. Monitoring and Sampling Manual 2018, Version 2 June 2018. Department of Environment and
Science. Brisbane, Queensland, Australia.
DNRME. 2002. Redcliffe to Teewah – Map 2 1:25,000. Queensland Department of Natural Resources and
Mines. Brisbane, Queensland, Australia.
Douglas Partners. 2020. Preliminary Geotechnical Investigation, Proposed Residence 33 Wyuna Drive,
Noosaville. Ref: 95120.00.R.001.
Douglas Partners. 2022. Additional Geotechnical Investigation, Proposed Residence 33 Wyuna Drive,
Noosaville. Ref: 95120.01.R.001.
Government of Western Australia. 2011 (Amended 2015). Cone of Depression. Department of Water and
Environmental Regulation. Accessed 27 September 2021, https://www.der.wa.gov.au/your‐
environment/acid‐sulfate‐soils/66‐cone‐of‐depression.
NHMRC. 2018. Guidelines for Managing Risks in Recreational Water. Australian Government, National
Health and Medical Research Council.
Noosa Shire Council. Noosa Council Interactive Mapping, Stormwater Infrastructure. Accessed 10
September 2021.
https://enterprise.mapimage.net/intramaps97/?project=Public&module=Noosa%20Plan%202020&conf
igId=64251f07‐9411‐4a61‐930e‐2bd9b45d8fff&startToken=8117c0c9‐fb07‐4d6a‐a629‐b82dc6c64537
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Appendix A: Figures
Figure 1 Site and proposed monitoring locations
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Figure 1 - Site location and proposed monitoring locations A product of
33 Wyuna Drive, Noosaville, QLD
26°23'39"S 153°4'42"E 26°23'39"S 153°4'51"E
Legend located on next page
0 25 metres
Scale: 1:866
Printed at: A3
Print date: 10/9/2021
Datum: Geocentric Datum of Australia 1994
Projection: Web Mercator EPSG 102100
For more information, visit https://qldglobe.information.qld.gov.au/help-info/Contact-
us.html
Includes material © State of Queensland 2021. You are responsible for ensuring that
the map is suitable for your purposes. The State of Queensland makes no
representation or warranties in relation to the map contents and disclaims all liability.
If imagery is displayed, imagery includes material © CNES reproduced under license
from Airbus DS, all rights reserved © 21AT © Earth-i, all rights reserved, 2019
26°23'45"S 153°4'42"E 26°23'45"S 153°4'51"E Department of Resources
Page 28
Figure 1 - Site location and proposed monitoring locations
33 Wyuna Drive, Noosaville, QLD
Legend Attribution
Includes material © State of Queensland (Department of Resources); ©
Road Crossing Commonwealth of Australia (Geoscience Australia); © 21AT, © Earth-i, all rights
reserved, 2021.
Bridge
© State of Queensland (Department of Resources) 2021
Tunnel
Road
Highway
Main
Local
Private
Railway
Page 29
ADG Consulting Pty Ltd Appendix B: DRDMW licenced bore search ADG1290.21 Dewatering Management Plan_Rev1_02.02.22
Page 30
DRDMW licence bore search - 500 m radius from site A product of
33 Wyuna Drive, Noosaville, QLD
26°23'21"S 153°4'19"E 26°23'21"S 153°5'20"E
Legend located on next page
0 250 metres
Scale: 1:9118
Printed at: A4
Print date: 10/9/2021
Datum: Geocentric Datum of Australia 1994
Projection: Web Mercator EPSG 102100
For more information, visit
https://qldglobe.information.qld.gov.au/help-info/Contact-
us.html
Includes material © State of Queensland 2021. You are
responsible for ensuring that the map is suitable for your
purposes. The State of Queensland makes no representation
or warranties in relation to the map contents and disclaims
all liability.
If imagery is displayed, imagery includes material © CNES
reproduced under license from Airbus DS, all rights reserved
© 21AT © Earth-i, all rights reserved, 2019
26°24'7"S 153°4'19"E 26°24'7"S 153°5'20"E Department of Resources
Page 31
DRDMW licence bore search - 500 m radius from site
33 Wyuna Drive, Noosaville, QLD
Legend Attribution
Maxar
Registered water bores Road
Includes material © State of Queensland (Department of
[RDMW and private]
Highway Resources); © Commonwealth of Australia (Geoscience
Australia); © 21AT, © Earth-i, all rights reserved, 2021.
Artesian bore Main
Artesian bore (abandoned but © State of Queensland (Department of Resources) 2021
Local
useable) © State of Queensland (Regional Development,
Private
Artesian bore (abandoned and Manufacturing and Water) 2021
destroyed) Cities and Towns
Artesian bore, ceased to ow
Artesian bore, ceased to ow
(abandoned but useable
Artesian bore, ceased to ow
(abandoned and destroyed)
Sub-artesian facility
Sub-artesian facility
(abandoned but useable)
Sub-artesian facility
(abandoned and destroyed)
Surface water facility
Surface water facility
(abandoned but useable)
Surface water facility
(abandoned and destroyed)
Road crossing
Bridge
Tunnel
Page 32
ADG Consulting Pty Ltd Appendix C: Dewatering Details Plan (Preliminary Draft) ADG1290.21 Dewatering Management Plan_Rev1_02.02.22
Page 33
== Existing Building eve IND Gas # Hd Existing Building LINO NOLL Vell Td LEGEND —— Property lot boundary Proposed treatment system location — Proposed internal spear system — SWL drawdown estimate -0.25 m SWL drawdown estimate -0.1 m Client: Date: Version: Scale: Michelle and Franco DePasquale c/- Chris Clout Design 02/02/2022 REVO nts Project Title: Project ID: Drawn by: Dewatering Management Plan ADG1290.21 Mc Site Address: Base plan source: Reviewed by: Size: Lot 16 on N10576, 33 Wyuna Drive, Noosaville, Queensland, QLD SCG Consulting Engineers DK Figure: File name: A3 Sketch - proposed shoring/dewatering systems, estimated cone of depression drawdown contours |ADG1290.21_Fig1 ADG Consulting Pty Ltd PO Box 6405 Yatala DC QLD 4207 P07 3801 1564 E [email protected] W adgconsulting.com.au All Correspondence ACN:630 555 225 ABN: 98 630 555 225, N TI ENVIRONMENT
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