GeotechnicalLandslip for the sole purpose c fr3Sgswhich

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Geotechnical Landslip and Erosion Risk Assessment and Management Strategies

340BWhitegateRoadGlenauroa

Geotechnical Landslip and Erosion Risk Assessment and Management Strategies 340b Whitegate Road Glenaroua

Important Notes:

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

The author, Strata Geoscience and Environmental, gives permission for this report to

be copied and distributed to interested parties only if it is reproduced in colour and in

full including all appendicies. No responsibility is taken for the contents and

recommendations of this report if it is not reproduced as requested.

Strata Geoscience and Environmental reserves the right to submit this report the

relevant regulatory agencies where it has a responsibility to do so.

© Strata - Geoscience and Environmental.03803. 24/09/2020 2


Table of Contents

Abstract ................................................................................................................. 5

1.Introduction ...................................................................................................... 7 1.1 SiteLocation and Context ....................................................................................... 7 1.2 Scope of Work......................................................................................................... 7 1.3 Guidelines and Standards Referenced .................................................................... 8

2.DesktopReviewandSiteInvestigation ............................................................... 9 2.1 Conceptual Surface Geology andGeomorphology ................................................. 9 2.2 Conceptual Site Hydrogeology ................................................................................ 9 2.3 Potential for Soil Erosion....................................................................................... 10 2.4 Potential for Slope Instability................................................................................ 11 2.5 Development Specific Criteria............................................................................... 13 2.6 Site Investigation................................................................................................... 13

3.ResultsandDiscussion...................................................................................... 14 3.1 Field Reconnaissance ............................................................................................ 14 3.2 Laboratory Results ............................................................................................... 14 3.3 Discussion.............................................................................................................. 14 3.3.1 Wind, Sheet, Rill, Tunnel and Gully Erosion ....................................................... 14 3.3.2 Deep Seated Landslide, Debris, Slide/Flow and Rockfall Risks........................... 15 3.4.1 Erosion Risk Assessment ................................................................................... 17 3.4.2 Slope Instability Risk Assessment...................................................................... 18

4.RiskAssessmentConclusions ............................................................................ 20

5.ManagementStrategies.................................................................................... 22 5.1 Erosion Risk Management Strategies................................................................... 22 5.2 SlopeInstabiity Risk Management Strategies ...................................................... 26 5.3 Further Recommendations .................................................................................. 27

6.References........................................................................................................ 28

7.Appendices....................................................................................................... 29

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Table Index

Table1 –Erosion RiskAssessment……………………………………….……………...…20 Table2 –Slope Instability RiskAssessment……………………………………….……21

Figure Index

Figure1 – Site Location………………………………………………...………………………...…7 Figure2 – ExertofGeoscienceAustralia 1:250000GeologicalMap .……....…9 Figure3 –Planning Extract ……...……………………………...……………………………....10 Figure4 –EastGippslandSoilErosionManagement Plan Extract ……...……………………………...………………………………………………………….....11 Figure5 –EastGippslandSoilErosionManagementPlan Extract ……...……………………………...………………………………………………………….....12 Figure6 –EastGippslandSoilErosionManagementPlan Extract ……...……………………………...………………………………………………………….....13

Appendices

Appendix 1 Development Plans Appendix 2 Indicative Bore Logs from Proposed Development Area Appendix 3 Extracts EPA, Aust Geomechanics Guidelines (2007) Appendix 4 Terms and Conditions

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Abstract

Simon Luthi contracted Strata Geoscience and Environmental Pty Ltd to

perform an Geotechnical Landslip and Erosion Risk Assessment and

Management Strategies report of proposed development areas underlying

340b Whitegate Road Glenaroua. The proponent is proposing a residential

dwelling (see Appendix 1) in an area identified as a having potential risk of slope

instability and erosion.

Geotechnical reconnaissance of the proposed development area comprised

field observation of geomorphic, soil and water factors associated with

dispersive or aolian derived soils. The investigation found that uniform soil

conditions exist over the proposed development site, namely a variable veneer

of SILTS (ML/MC) overlying Silty CLAYS (CL/CH) terminating on inferred

bedrock, generally less than 1m below the existing ground surface. Inferred

bedrock outcroppings were also observed within the localised landscape and

proximal to the proposed dwelling site.

A risk assessment for slope instability and erosion of soils over the proposed

development areas has found:

• Slopes are generally above the nominated 7 degree threshold for debris slide/flow risks where soils are suitably deep enough for these processes to occur. In areas where surface bedrock is close to the surface such risks are low.

• Where slopes are greater than the nominated 7 degree threshold – treatment measures are suggested to reduce risk of slope instability to low levels in these areas. Principally this involves taking all foundations into competent bedrock (which is likely to be proximal to the ground surface), minimising any site disturbance and installing upslope drainage.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



• The risk of creating slope instability (landslide) over the site given the current development plans is low and should be accepted provided all treatment recommendations are adopted.

• Dispersive soil phases are likely to exist over the site. The presence

and severity of these dispersive phases are likely to vary enormously

over short distances. Such soils have the potential to cause tunnel and

gully erosion and require careful management with increasing site

development.

• Loose sandy topsoils are susceptible to sheet and rill erosion from wind

and water.

• The risk associated with site development creating soil erosion is high and treatment measures MUST be adopted to limit this risk to life and property.

Treatment measures to limit risk are detailed in Sections 4 and 5.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



1. Introduction

1.1 Site Location and Context

The proposed development area is located at 340b Whitegate Road Glenaroua.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Figure 1 Site Location

1.2 Scope of Work

It is the scope of this investigation to perform a risk assessment for the potential

to create soil erosion or slope instability given the current development proposal

(see Appendix 1). The scope has been determined in consultation with the

proponent and is subject to temporal and budgetary considerations. This

investigation will inform further sampling and analysis as well as the preparation

of site specific management plans if warranted.



1.3 Guidelines and Standards Referenced

This investigation is made with reference to, or in general accordance with, the

following standards and guidelines:

• Standards Australia (1993) AS1726-1993 Geotechnical Site

Investigations

• Standards Australia (2004) AS/NZS4360 - Risk Management

• Standards Australia (1997) AS3798 “Guidelines for Earthworks on

commercial and residential subdivision”

• Australian Geomechanics Society (2007) Landslide Risk Management.

Australian Geomechanics 42(1) March 2007.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



2. Desktop Review and Site Investigation

2.1 ConceptualSurfaceGeologyand Geomorphology

Referring to the Geoscience Australia 1:250000 Mapping Series accessed via

GeoVic, the proposed dwelling is located on a moderately sloping spur

underlain by Humvale Siltstones (Dxh) which terminates into newer Quaternary

aged alluvial/fluvial deposits associated with the nearby Kurkuruk Creek. The

site occupies a mid-slope position in the localised landscape, with moderate –

steep slopes surrounding the proposed development areas.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Figure 2 Geoscience Australia 1:250000 Geological Map (Accessed via Geovic)

2.2 Conceptual SiteHydrogeology

Whilst site specific hydro-geological modelling has not been conducted and no

site specific data is available, it is likely that a shallow unconfined groundwater

aquifer exists under the site in unconsolidated fluvial/alluvial sediments. Base

flows for localised drainage lines and creeks are likely supplied by this shallow

ephemeral unconfined aquifer moving through or over subsoils. Localised



groundwater is therefore likely moving in a south easterly direction. At the time

of this investigation this aquifer was observed. Shallow groundwater can

impact upon dispersive soils by causing tunnel erosion and it is therefore critical

to manage groundwater flows where it is impacting upon soils

2.3 PotentialforSoilErosion

Referring to the Vicplan planning overlays the site is identified as having erosion

management and significant landscape management overlays (Figure 3-6).

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Figure 3 Planning Overlays



Given the above further investigation over the proposed development area is

warranted.

2.4 PotentialforSlopeInstability

Landslide modelling by Mazengarb (2013) has produced zones with distinct

landslide risks shown in Figure 4 below. This models conceptual parameters

to determine slope thresholds for geological units.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Figure 7 Landslide zoning conceptual diagram (Mazengarb, 2013)

For modelling purposes slopes under 7 degrees with a 20m regression/run out

buffer are inferred to have minimal potential for slope instability. This follows

suggestions contained in Australian Geomechanics Guidelines (2007) for Good

Hill Side Construction Practice as well as Mazengarb (2013).



There are three types of slope instability are defined, namely:

• Deep Seated Instability Hazards- failures of geological units where the

failure plane extends below any unmapped superficial soil or regolith

material that may exist onsite usually exceeding 5 meters (Mazengarb,

2004). This could occur due to down slope movement between bedding

planes in either unconsolidated overburden sediments of the underlying

older bedrock.

• Debris Flow/Slide Hazards - the action of unconsolidated sediments

(often containing loose rock) mixing with water after a significant rainfall

event(s) and flowing down slope (Mazengarb 2004). Also encompasses

soil creep and runouts in watercourses.

• Rock Fall Hazards - an independent movement of rock or soil fragments

through freefall, bouncing, rolling or sliding (Mazengarb, 2004).

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



2.5 DevelopmentSpecificCriteria

Development plan are presented in Appendix 1.

2.6 Site Investigation

Geomorphic slope factors were assessed via a visual inspection of the site, soil

and water factors were investigated by the drilling of geotechnical test bores to

2m or refusal on rock (which ever first). Soils were sampled at various depths

from the ground surface to as an initial screening investigation to inform the

requirement of follow up sampling where deep soil profiles were encountered.

Given the shallow nature of soils within the dwelling footprint, testing was not

conducted in this area.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



3. Results and Discussion

3.1 Field Reconnaissance

Field reconnaissance involved a site walk over to confirm geomorphology and

the drilling of geotechnical bores in proposed development areas to facilitate

soil sampling (where relevant). Logs are presented in Appendix 2.

General comments from field reconnaissance include:

o The site is moderately- steeply sloping, covered with pasture and

inferred bedrock outcroppings were observed within the localised

landscape.

o The dwelling location is on a south east sloping spur containing

north east and south west faces.

o The proposed dwelling site did not show any signs of instability or

erosion and surface bedrock outcroppings were observed.

o However, evidence of current or former erosion or slope instability

was seen in gullies approximately 100m from the proposed

dwelling location. Soils where significantly deeper in these areas

and had runoff concentrated.

o Slopes over the site are located on slopes greater than 7 degrees.

3.2 LaboratoryResults

Given the very shallow soils observed within the proposed dwelling site, soil

sampling and laboratory testing was not conducted.

3.3 Discussion

3.3.1 Wind,Sheet,Rill,TunnelandGullyErosion

Geotechnical reconnaissance found shallow loose Silts (ML) over CLAYS

(CL/CH) up to 1.0 mbgs (Appendix 2). In some areas surface bedrock was

observed. Light textured loosely packet topsoils (where present) are

susceptible to wind erosion if stripped of vegetation for prolonged periods.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Whilst laboratory testing was not conducted from the dwelling site given the

very shallow soils in this area there is a risk of intercepting severely dispersive

soil phases (Class 1/2) over the site with significant amount of soil disturbance

combined with the fact that these phases are likely to vary enormously over

short distances.

Light textured topsoils where present can be eroded by wind and water if not

managed correctly. This will lead to sheet and rill erosion with the loss of topsoil

and potential sedimentation of waterways. It can also expose deeper subsoils

with dispersive phases which can lead to tunnel and gully erosion, particularly

on slopes. Active gully and tunnel erosion was observed approximately 100m

from the proposed dwelling site in areas of deeper soils on steeper slopes

where runoff is concentrated.

Given the potential presence of highly dispersive soil phases over the site, the

risk analysis presented in Section 3.4.1 has been prepared based upon the

assumption that highly dispersive phase are likely to be disturbed by the current

development plan.

3.3.2 Deep Seated Landslide,Debris,Slide/Flowand RockfallRisks

No evidence of active or former areas of slope instability were observed over

proposed building area. The majority of the site had slopes >7 degrees.

The site should have the following strategies implemented to limit risks:

• Employ deepened foundation designs into competent bedrock. This substrate is relatively shallow to the ground surface and will provide a competent and stable substrate for foundations, minimising slope instability risks to the dwelling.

• Exclude site cutting and bulk earthworks where possible or minimise when not possible.

• Revegetate immediately after soil disturbance.

• Manage soil water relations.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



A qualitative Geotechnical Landslip and Erosion risk assessment, in

accordance with Australian Geomechanics Society (2007) is presented in

Section 3.4.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



3.4.1 Erosion RiskAssessment Table 1 – Summary erosion hazards, consequences and risk, with suggested treatment options

and revised risk after treatment option implementation

Hazard: Likelihood Soil erosion of

occurrence

Rill and Sheet Erosion

Tunnel and Gully Erosion

Possible

Wind Erosion Possible

Possible

Consequencesto life and property

Medium

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Medium

Major

Level of risk to life and property

Moderate

Moderate

High

Mitigation optionsto lower risk levels (see

Section 4 for further details)

Avoid excavations where possible and excavate only in dry weather where necessary.

Cover excavations as soon as possible after construction.

Chemical amelioration, re-vegetate and re-topsoil as soon as practical after disturbance

Capture and reticulate all runoff around disturbed areas Excavate only in stable weather


Chemical amelioration, re-vegetate and re-topsoil as soon as practical after disturbance

Vegetate downslope swales (WSUD).

Avoid culverts and trenching where possible

Chemical amelioration, re-vegetate and re-topsoil. Use of weirs, rock lined swales to reduce water velocity.


Excavate only in dry weather See Section 5 for further recommendations

Concepts and terminology from AGS (2007) Practice Note Guidelines for Landslide Risk Management

(See Appendix 3)


Level or risk after

mitigation

Low

Low

Moderate-Low


3.4.2 SlopeInstabilityRiskAssessment

Table 2 –Summary of geotechnical hazards, consequences and risk, with suggested treatment

options and revised risk after treatment option implementation

Debris Slide/Slump/Creep

Deep Seated Landslide

Possible Medium Moderate

Likelihood Consequenc Likely level Level of risk Possible mitigation Hazard of es to of risk after to property options occurrence property mitigation

Unlikely Major

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

High

Adopt building/land application envelopes 20m buffers from areas with slopes > 7 degrees – both up and downslope where possible

Utilise deepenedfoundation designs (eg end bearing piles) in areas above this threshold

Lightweight, articulated, flexible construction methods

Adequate reticulation of all stormwater to discharge points capable of accepting 200mm/d.

Minimise/exclude bulk earthworks and site cutting

Minimise/exclude bulk earthworks and site cutting – design driveways to have flattest route across its distance.

Adequately stabilise all cuts with engineered retaining walls or Gabion Walls

Adopt building/land application envelopes 20m buffers from areas with slopes > 7 degrees – both up and downslope where possible

Utilise deepened foundation designs (eg end bearing piles) in areas above this threshold

Minimise/exclude soil disturbance and bulk earthworks

Fill batters must be adequately stabilised

Retain/promote deep rooted vegetation where it will not impact upon foundations.

Low

Low



Foundations to be designed to cater for adverse soil water relations and founded on bedrock)

Lightweight, articulated, flexible construction methods

Adequate and deep upslope drainage

Irrigate wastewater downslope of all structures

Minimise/exclude bulk earthworks and site cutting – design driveways to have flattest route across its distance.

Adequately stabilise all cuts with engineered retaining walls or Gabion Walls

Rock falls and topples

Contain Medium Unlikely all liberated boulders

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Low Low Concepts and terminology from AGS (2007) Practice Note Guidelines for Landslide Risk Management (See Appendix 3

*Risk needs further assessment when finalised development plan available.)



4. Risk Assessment Conclusions

This investigation and risk assessment for the potential to create slope instability (landslip) over the proposed development areas has found:

• No evidence of current or former instability was observed over the proposed dwelling location.

• The largest risk associated with the creation of instability is associated with deeper soils >1m on slopes >7 degrees

• Risks to the dwelling and land application areas are low provided that all treatment measures are employed. Specifically, this involves employing deepened foundation designs into competent bedrock. This substrate is relatively shallow to the ground surface and will provide a competent and stable substrate for foundations, minimising slope instability risks to the dwelling. Further risk management of potential for slope instability can be ensured by excluding bulk earthworks and managing upslope runoff.

• If all treatment measures are employed the risk to life and property is low and tolerable.

This investigation and risk assessment for soil erosion over the proposed

development areas has found:

• No erosion was observed over the proposed dwelling site however severe tunnel and gully erosion was observed in deeper soils on steeper slopes approximately 100m from the proposed dwelling location.

• Dispersive soil phases are likely to exist over the site and have the risk of causing tunnel and gully erosion over time if inappropriately managed. The presence and severity of these dispersive phases are likely to vary enormously over short distances.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



• Deep sandy topsoils where disturbed present a further sheet and rill

erosion risk via wind or water.

• The risk associated with site development creating soil erosion is high

• Treatment measures MUST be adopted to limit this risk to life and

property.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



5. Management Strategies

5.1 Erosion RiskManagementStrategies

Given the above the following GENERAL erosion risk management strategies

are recommended to limit risk to life and property:

• Maintaining topsoils and minimising subsoil disturbance. Where

vegetation is stripped, it should be replaced or stabilised with jute

matting, hydro-seeding or similar as soon as possible after disturbance.

• Chemical amelioration of all disturbed areas using gypsum at an

application rate of 1kg/m2

• Conduct bulk earthworks throughout drier periods where possible.

• If possible do not construct culverts, trenches or drains in dispersive

soils.

• Avoid/limit bulk earthworks or construction of new dams if possible.

• Adopt the recommendations of EPA Publication 960 Guidelines for

Environmental Management – Doing it Right on Subdivisions (Appendix

3)

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



With reference to the development plan (see Appendix 1) the following

recommendations are made:

• Roadways/driveways MUST:

o Install roading via the flattest possible routes.

o Have cambers slightly sloping down slope and roadside swales

and batters MUST be revegetated following the principles of

water sensitive urban design.

o The use of road bars and diversion mounds to channel water

away from roads is encouraged

o Subgrade MUST be compacted, treated with gypsum and a

suitable base layer must be rolled to limit infiltration into

dispersive soils under roads.

o Roadways should be completed as soon as possible after

topsoil stripping. Road routes should be stripped in stages to

limit erosion risk caused by disturbance and disturbed soil must

not be left de-vegetated for prolonged periods, especially

throughout wet periods.

o If culverts and drains are absolutely necessary ensure that they

are excavated in dispersive soils are capped with non

dispersive clays mixed with gypsum and topsoil and re –

vegetated and monitored.

o Construct rock weirs or line drains with rocks to reduce water

velocity.

o Follow the principals of water sensitive urban design

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



• Services installation MUST:

o Avoid trenching systems and use above ground piping or aerial

cabling where possible.

o Where underground service installation is absolutely necessary

ensure dispersive soils are capped with non dispersive clays

mixed with gypsum and topsoil and re –vegetated and

monitored.

o Avoid onsite trenching systems for stormwater - construct lined

rock weirs or line drains with rocks to reduce water velocity.

o Follow the principals of water sensitive urban design for

stormwater reticulation – use grassed swales, lined weir

systems and encourage wetland to treat stormwater and reduce

water velocity.

• Future Dwellings/Outbuildings Construction Methods:

Given the presence of dispersive soils, mitigation should be undertaken as

follows:

o Cut and fill areas are to be covered with 150mm topsoil with

gypsum mixed at 1.0 kg/m2 and re-vegetated. Areas are then to

be mulched and track rolled. The areas are to be

monitored and any signs of tunnel erosion are to be rectified

immediately.

o Limit concentration of run-off from hardstands. Excavated ground

levels are to fall away from the house so that no water pools.

o Trenching in dispersive soils is to be avoided. Avoid trenching of

stormwater and water supply pipes from header tanks into the

clay layer. Lay piping scratched max 100mm deep into the topsoil

layer, cover with topsoil mounded over pipes and re-seed

immediately.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



• Wastewater Systems MUST;

o Be designed as an near surface system (eg sand filter, mound

or spray/drip irrigation NOT TRENCHES OR BEDS)

o Water to be treated to secondary levels

o All land application area must have vegetation maintained

o Land application envelopes must be located downslope of

building envelopes

o Underlying soils MUST be treated with Gypsum at a rate of

1Kg/m2

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



5.2 SlopeInstabiityRiskManagementStrategies

Given the above the following GENERAL treatment measures are

recommended to limit risk to life and property from slope instability:

• Minimise/exclude bulk earthworks and site cutting – design

roading/driveways to have flattest route across its distance where

possible.

• Adequately stabilise all cuts with engineered retaining walls or Gabion

Walls

• Where this is not possible utilise the following treatment measures:

o Incorporate deepened foundation systems into competent bedrock

o Avoid trench based land application of storm or wastewater

o Adopt the recommendations of the Australian Geomechanics

Society for Good Hillside Construction Practice (2007) (Appendix

3)

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



5.3 FurtherRecommendations

Lastly it is recommended that:

• A Soil and Water Management Plan, detailing specific treatment

measures must be commissioned.

• All treatment measures designed or installed by others MUST be ratified

by the author.

• All future development plans MUST be provided to strata to ratify

against this report. Failure to ensure this will void the modelling and

recommendations contained within this report.

• Ongoing monitoring of all works for signs of erosion must be undertaken

by owners or occupiers in conjunction with Strata Geoscience and

Environmental P/L.

Any questions or comments in relation to this investigation or its findings should

be directed towards the author.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

S Nielsen MEngSc CPSS-2 Director Strata Geoscience and Environmental Pty Ltd E:[email protected]



6. References

• Standards Australia (1993) AS1726-1993 Geotechnical Site

Investigations

• Standards Australia (2004) AS/NZS4360 - Risk Management

• Standards Australia (1997) AS3798 “Guidelines for Earthworks on

commercial and residential subdivision”

• EPA Publication 960 Guidelines for Environmental Management – Doing

it Right on Subdivisions

• East Gippsland Soil Erosion Management Plan

• Australian Geomechanics Society (2007) Landslide Risk Management.

Australian Geomechanics 42(1) March 2007.

• Mazengarb (2010) Landslide Risk Modelling. MRT

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



7. Appendices

This report contains the following appendices:

Appendix 1 Development Plans Appendix 2 Indicative Bore Logs from Proposed Development Area Appendix 3 Extracts EPA, Aust Geomechanics Guidelines (2007) Appendix 4 Terms and Conditions

All appendices must accompany this report and be reproduced faithfully in full colour.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix1 DevelopmentPlans

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix2 Indicative BoreLogs fromProposedDwellingLocation

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 3 Extracts from EPA Publication 960

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Extracts From Australian Geomechanics Journals (2007)

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 4 Terms and Conditions

Scope of Work These Terms and Conditions apply to any services provided to you (“the Client”) by Strata Geoscience and Environmental Pty Ltd (“Strata”). By continuing to instruct Strata to act after receiving the Terms and Conditions or not objecting to any of the Terms and Conditions the Client agrees to be bound by these Terms and Conditions, and any other terms and conditions supplied by Strata from time to time at Strata’s sole and absolute discretion. The scope of the services provided to the Client by Strata is limited to the services and specified purpose agreed between Strata and the Client and set out in the correspondence to which this document is enclosed or annexed (“the Services”). Strata does not purport to advise beyond the Services.

Third Parties The Services are supplied to the Client for the sole benefit of the Client and must not be relied upon by any person or entity other than the Client. Strata is not responsible or liable to any third party. All parties other than the Client are advised to seek their own advice before proceeding with any course of action.

Provision of Information The Client is responsible for the provision of all legal, survey and other particulars concerning the site on which Strata is providing the Services, including particulars of existing structures and services and features for the site and for adjoining sites and structures. The Client is also responsible for the provision of specialised services not provided by Strata. If Strata obtains these particulars or specialised services on the instruction of the Client, Strata does so as agent of the Client and at the Client's expense. Strata is not obliged to confirm the accuracy and completeness of information supplied by the Client or any third party service provider. The Client is responsible for the accuracy and completeness of all particulars or services provided by the Client or obtained on the Client’s behalf. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever suffered by the Client or any other person or entity resulting from the failure of the Client or third party to provide accurate and complete information. In the event additional information becomes available to the Client, the Client must inform Strata in writing of that information as soon as possible. Further advice will be provided at the Client’s cost. Any report is prepared on the assumption that the instructions and information supplied to Strata has been provided in good faith and is all of the information relevant to the provision of the Services by Strata. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever if Strata has been supplied with insufficient, incorrect, incomplete, false or misleading information.

IntegrityAny report provided by Strata presents the findings of the site assessment. While all reasonable care is taken when conducting site investigations and reporting to the Client, Strata does not warrant that the information contained in any report is free from errors or omissions. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from errors in a report. Any report should be read in its entirety, inclusive of any summary and annexures. Strata does not accept any responsibility where part of any report is relied upon without reference to the full report.

Project Specific Criteria Any report provided by Strata will be prepared on the basis of unique project development plans which apply only to the site that is being investigated. Reports provided by Strata do not apply to any project other than that originally specified by the Client to Strata. The Report must not be used or relied upon if any changes to the project are made. The Client should engage Strata to further advise on the effect of any change to the project. Further advice will be provided at the Client’s cost. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever where any change to the project is made without obtaining a further written report from Strata. Changes to the project may include, but are not limited to, changes to the investigated site or neighbouring sites, for instance, variation of the location of proposed building envelopes/footprints, changes to building design which may impact upon building settlement or slope stability, or changes to earthworks, including removal (site cutting) or deposition of sediments or rock from the site.

Subsurface Variations with Time Any report provided by Strata is based upon subsurface conditions encountered at the time of the investigation. Conditions can and do change significantly and unexpectedly over a short period of time. For example groundwater levels may fluctuate over time, affecting latent soil bearing capacity and ex-situ/insitu fill sediments may be placed/removed from the site. Changes to the subsurface conditions that were encountered at the time of the investigation void all recommendations made by Strata in any report. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from any change to the subsurface conditions that were encountered at the time of the investigation. In the event of a delay in the commencement of a project or if additional information becomes available to the Client about a change in conditions

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



becomes available to the Client, the Client should engage Strata to make a further investigation to ensure that the conditions initially encountered still exist. Further advice will be provided at the Client’s cost. Without limiting the generality of the above statement, Strata does not accept liability where any report is relied upon after three months from the date of the report, (unless otherwise provided in the report or required by the Australian Standard which the report purports to comply with), or the date when the Client becomes aware of any change in condition. Any report should be reviewed regularly to ensure that it continues to be accurate and further advice requested from Strata where applicable.

InterpretationSite investigation identifies subsurface conditions only at the discrete points of geotechnical drilling, and at the time of drilling. All data received from the geotechnical drilling is interpreted to report to the Client about overall site conditions as well as their anticipated impact upon the specific project. Actual site conditions may vary from those inferred to exist as it is virtually impossible to provide a definitive subsurface profile which accounts for all the possible variability inherent in earth materials. This is particularly pertinent to some weathered sedimentary geologies or colluvial/alluvial clast deposits which may show significant variability in depth to refusal over a development area. Rock incongruities such as joints, dips or faults may also result in subsurface variability. Soil depths and composition can vary due to natural and anthopogenic processes. Variability may lead to differences between the design depth of bored/driven piers compared with the actual depth of individual piers constructed onsite. It may also affect the founding depth of conventional strip, pier and beam or slab footings, which may result in increased costs associated with excavation (particularly of rock) or materials costs of foundations. Founding surface inspections should be commissioned by the Client prior to foundation construction to verify the results of initial site characterisation. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from any variation from the site conditions inferred to exist.

Strata is not responsible for the interpretation of site data or report findings by other parties, including parties involved in the design and construction process. The Client must seek advice from Strata about the interpretation of the site data or report.

Report Recommendations Any report recommendations provided by Strata are only preliminary. A report is based upon the assumption that the site conditions as revealed through selective point sampling are indicative of actual conditions throughout an area. This assumption cannot be substantiated until earthworks and/or foundation construction is almost complete. Where variations in conditions are encountered, Strata should be engaged to provide further advice. Further advice will be provided at the Client’s cost. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever if the results of selective point sampling are not indicative of actual conditions throughout an area or if the Client becomes aware of variations in conditions and does not engage Strata for further advice.

Geo-environmental Considerations Where onsite wastewater site investigation and land application system designs are provided by Strata, reasonable effort will be made to minimise environmental risks associated with the disposal of effluent within site boundaries with respect to relevant Australian guidelines and industry best practise at the time of investigation. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from changes to either the project or site conditions that affect the onsite wastewater land application system’s ability to safely dispose of modelled wastewater flows.

Strata does not guarantee septic trench and bed design life beyond 10 years from installation, given the influence various household chemicals have on soil structural decline and premature trench failure in some soil types. Strata is not liable, and accepts no responsibility, for poor system performance where the Client cannot show that septic tanks have been de-sludged every three years or AWTS systems have been serviced in compliance with the manufacturer’s recommendations. Strata is not liable, and accepts no responsibility, for any loss associated with the selection of inappropriate plants for irrigation areas. Strata is not liable, and accepts no responsibility, for any expense whatsoever or loss associated with modification of design works requested by the permit authority. Strata is not liable and accepts no responsibility for any loss or poor system performance where both interim and final inspections are not commissioned throughout system construction.

Strata does not consider site contamination, unless the Client specifically instructs Strata to consider the site contamination in writing. If a request is made by the Client to consider site contamination, Strata will provide additional terms and conditions that will apply to the engagement.

Copyright and Use of Documents Copyright in all drawings, reports, specifications, calculations and other documents provided by Strata or its employees in connection with the Services remain vested in Strata. The Client has a licence to use the documents for the purpose of completing the project. However, the Client must not otherwise use the documents, make copies of the documents or amend the documents unless express approval in writing is given in advance by Strata. The Client must not publish or allow to be published, in whole or in part, any document provided by Strata or the name or professional affiliations of Strata, without first obtaining the written consent of Strata as to the form and context in which it is to appear.

If, during the course of providing the Services, Strata develops, discovers or first reduces to practice a concept, product or process which is capable of being patented then such concept, product or process is and remains the property of Strata and:

(a) the Client must not use, infringe or otherwise appropriate the same other than for the purpose of the project without first obtaining the written consent of Strata; and

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



(b) the Client is entitled to a royalty free licence to use the same during the life of the works comprising the project.

Digital Copies of ReportIf any report is provided to the Client in an electronic copy except directly from Strata, the Client should verify the report contents with Strata to ensure they have not been altered or varied from the report provided by Strata.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.


This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Land Capability Assessment and Onsite Wastewater System Design for

Lot 3 340B Whitegate Road Glenaroua

January 2020

LCA and Onsite System Design for Lot 3 340b Whitegate Road Glenaroua

Important Notes:

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.







© Strata - Geoscience and Environmental. Report 03496 14/01/2020 2


1. Introduction

Strata Geoscience and Environmental Pty Ltd was commissioned to perform a limited scope Land Capability Assessment for:

Table 1 : Site and Client Details Client/Agent Simon Luthi Site Address Lot 3 340b Whitegate Road Glenaroua

(see Site Plan) Nature of Development New dwelling

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

The investigation was conducted based upon specific development plans

supplied by the client (Figures 2&3) and with reference to the following

documents:

1. EPA Victoria (2016) Code of Practice for Onsite Wastewater Management

2. Australian Standard AS1547-2012 Onsite Wastewater Management

The investigation also follows the principles outlined in:

1. 2006 MAV & DSE Model LCA Report

2. EPA Publication 746.1 Guidelines for Land Capability Assessment

3. MAV DEPI & EPA 2014 Land Capability Assessment Framework

4. AS1726-1993 Geotechnical Site Investigations.

2. Description of the Development

Table 2 Site Description

Site Address Lot 3 340b Whitegate Road Glenaroua

Owner/Developer/Agent Simon Luthi Address As above Council Area Mitchell Zoning Fz Allotment Size 41 Ha approx. Anticipated Wastewater Load Up to 450L/D (See Section 6) Availability of Sewer Unsewered and likely to be

unsewered in mid term



3. Site Plans and Key Site Features

A range of soil and landscape features were assessed for their potential to

impact upon land application area siting and level of wastewater treatment

required over the site. Figures 1-2 give locality and proposed site plans

respectively whilst Table 3 summarises key features as in relation to effluent

management over the site.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Figure 1 Locality Plan

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Figure 2 Proposed Site/Floor Plan

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Table 3 Site Features Climate The nearest weather station with long term data is the High Camp Station

with a mean annual rainfall of 620 mm (BOM 2019). The region has a near Mediterranean climate with maximum temperatures and minimum rainfall in the summer.

Exposure The site is relatively shielded with exposure to winds which predominate from the NW/SW directions

Vegetation Grass, Trees

Landform Slope

Slope Moderate

Fill No fill/disturbed soils evident in proposed land application areas

Rocks and Rock Outcrops

Surface rock outcroppings

Erosion Potential Tunnel and gully erosion evident

Surface Water >30m

Flood Potential Unknown Stormwater Run-on and Upslope Seepage

Seepage over subsoils likely

Groundwater Not encountered

Site Drainage and Subsurface Drainage

The site receives minimal run on and does not show signs of springs or other areas of ephemeral subsurface water retention. Given clay subsoils perched watertable may exist in some areas of the site

Recommended Buffer Distances

Given the significant land area, all buffer distances as stipulated in EPA (2016) are achievable.

Available Land Application Area

There is surplus space to land application area requirements

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



4. Soil Assessment and Constraints

Soils have been assessed for their suitability for onsite wastewater

management through both desktop review and intrusive field investigation.

Field investigation consisted of drilling soil bores using a 50mm soil probe to

1.5m or refusal on rock with retrieval of undisturbed soil cores for logging,

sampling and testing for pH, EC, CEC, Emerson Class.

Bore logs and soil permeability data/soil test results (where relevant) are

presented in Appendix 1. As a general comment soil appeared to be relatively

uniform across the proposed development area with Clayey SANDS (SC)

grading to Clayey SILTS (ML) /Silty CLAYS (CL) subsoils.

With reference to the classification system of Isbell (2002) soils are classified

as Brown Sodosols being duplex soils with sodic phases. Soils will exhibit

duplex profiles with lighter Clayey SAND (SC) grading to Silty CLAYS

(CL/CH)/Clayey SILTS (ML) at variable depths from the existing ground

surface. Subsoils clays will exhibit a moderate structure and will show the

existence of vertical macropores throughout drier periods, significantly

increasing their unsaturated hydraulic conductivities. Subsoils will show

moderate to high cation exchange complex for the absorption of nutrients, may

contain dispersive phases and a slightly acidic pH trend.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Table 4 Typical Soil Characteristics

Soil Depth (m) 0.6m+ (variable) Depth to Water Table (m) 2.5m+ Coarse Fragments (%) 25% Soil Permeability and Concept Design Loading Rates

Approximately 0.5 m/d DIR of 3mm/d appropriate

Topsoils (A1-A3) Subsoils (B1-B3) Description Clayey SAND (SC) Silty CLAY (CH) Soil Category (AS1547-2011)

2 5

DIR (mm/d)/DLR (L/D)

4.5/30 3/8

pH 6.2 5.5 EC (micosiemens/m)

33 68

Emmerson Class 8 4

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



5. Land Capability Assessment Matrix 5.1 Assessment Matrices

Referring to MAV & DSE (2006), EPA Victoria Publication 746.1 Land

Capability Assessment for Onsite Domestic Wastewater Management and

MAV DEPI & EPA 2014 Land Capability Assessment Framework, a qualitative

LCA assessment table have been produced for the site.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.


Table 6: Risk Assessment of Site Characteristics (MAV, DEPI, EPA 2014)

Characteristic

Level of Constraint Assessed Level of

Constraint for Site and Mitigation if

required

Nil or Minor Moderate Major

Aspect (affects solar radiation received)

North / North-East / North-West

East / West / South-East / South-West South

Minor

Climate (difference between annual rainfall and pan evaporation)

Excess of evaporation over rainfall in the wettest months

Rainfall approximates to evaporation

Excess of rainfall over evaporation in the wettest months

Moderate

Erosion 1

(or potential for erosion)

Nil or minor Moderate Severe Major – drip irrigate into topsoils

Exposure to sun and wind

Full sun and/or high wind or minimal shading

Dappled light Limited patches of light and little wind to heavily shaded all day

Nil

Fill 2

(imported) No fill or minimal fill,

or fill is good quality topsoil Moderate coverage and fill is

good quality Extensive poor quality fill and

variable quality fill Minor

Flood frequency (ARI) 3 Less than 1 in 100 years Between 100 and 20 years More than 1 in 20 years Minor

Groundwater bores 4 No bores onsite or on neighbouring properties

Setback distance from bore complies with requirements in

EPA Code of Practice 891.3 (as amended)

Setback distance from bore does not comply with requirements in EPA Code of Practice 891.3 (as

amended) Minor

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.


Characteristic



required


Land area available for LAA

Exceeds LAA and duplicate LAA and buffer distance

requirements

Meets LAA and duplicate LAA and buffer distance requirements Insufficient area for LAA

Minor

Landslip (or landslip potential) 5

Nil Minor to moderate High or Severe Minor

Rock outcrops (% of surface)

<10% 10-20% >20% Major

Slope Form (affects water shedding ability)

Convex or divergent side-slopes Straight side-slopes Concave or convergent side-slopes

Minor

Slope gradient 6 (%)

(a) for absorption trenches and beds <6% 6-15% >15% Minor

(b) for surface irrigation <6% 6-10% >10% Minor

(c) for subsurface irrigation <10% 10-30% >30% Minor

Soil Drainage 7

(qualitative) No visible signs or likelihood of dampness, even in wet season

Some signs or likelihood of dampness

Wet soil, moisture-loving plants, standing water in pit; water ponding

on surface, soil pit fills

Moderate – avoid wet areas

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Characteristic



required


Stormwater run-on

Low likelihood of stormwater run-on

High likelihood of inundation by stormwater run-on

Minor

Surface waters -setback distance (m) 9

Setback distance complies with requirements in EPA Code of Practice 891.3 (as amended)

Setback distance does not comply with requirements in EPA Code of

Practice 891.3 (as amended)

Minor – 100m setback for secondary treatment

Vegetation coverage over the site

Plentiful vegetation with healthy growth and good potential for

nutrient uptake Limited variety of vegetation Sparse vegetation or no

vegetation

Minor



required

Characteristic Nil or Minor Moderate Major

Soil Drainage 8 (Field Handbook definitions)

Rapidly drained. Water removed from soil rapidly in relation

to supply, excess water flows

downward rapidly. No horizon remains wet for more than a

few hours after addition

Well drained. Water removed

from the soil readily, excess

flows downward. Some horizons may remain wet for several days

after addition

Moderately well drained. Water

removed somewhat slowly

in relation to supply, some horizons may

remain wet for a week or more after addition

Imperfectly drained. Water removed very slowly in

relation to supply, seasonal ponding, all horizons wet for periods of several

months, some mottling

Poorly/Very poorly drained. Water remains at or near the

surface for most of the year,

strong gleying. All horizons wet

for several months

Moderate

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Table 7: Risk Assessment of Soil Characteristics Level of Constraint Assessed Level of


required Characteristic


Electrical Conductivity (ECe) (dS/m) as a measure of soil salinity 1

<0.8 0.8 - 2 >2 Minor

Emerson Aggregate Class (consider in context of sodicity)

4, 5, 6, 8 7 1, 2, 3 Major

Gleying 2

(see Munsell Soil Colour Chart)

Nil Some evidence of greenish grey / black or bluish grey /

black soil colours

Predominant greenish grey / black, bluish grey / black

colours

Minor

Mottling (see Munsell Soil Colour Chart)

Very well to well-drained soils generally have uniform

brownish or reddish colour

Moderately well to imperfectly drained soils have grey and/or

yellow brown mottles and in the mottled areas occur higher

in the profile the less well-drained the soil

Poorly drained soils have predominant grey colours

with yellow brown or reddish brown mottles located along root channels, large pores

and cracks

Minor

pH 3

(favoured range for plants)

5.5 - 8 is the optimum range for a wide range of plants; 4.5 - 5.5 suitable for many

acid-loving plants

<4.5, >8 Minor This

copie

d doc

umen

t is m

ade a

vaila

ble fo

r the s

ole pu

rpose

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Characteristic Level of Constraint Assessed Level of


required Nil or Minor Moderate Major

Rock Fragments (size & volume %)

0 – 10% 10 – 20 % >20% Major

Sodicity 4

(ESP %) <6% 6 – 8% >8% Moderate

Soil Depth to Rock or other impermeable layer (m) 5

>1.5 m 1.5 – 1 m <1 m Moderate

Soil Structure (pedality)

Highly or Moderately structured

Weakly-structured Structureless, Massive or hardpan

Minor

Soil Texture, 6

Indicative Permeability

Cat. 2b, 3a, 3b, 4a Cat. 4b, 4c, 5a Cat. 1, 2a, 5b, 5c, 6 Minor

Watertable Depth (m) below the base of the LAA

>2 m 2 – 1.5 m <1.5 m Moderate

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.Legend:

Nil or Minor: If all constraints are minor, conventional/standard designs are generally satisfactory. Moderate: For each moderate constraint an appropriate design modification over and above that of a standard design, should be outlined. Major: Any major constraint might prove an impediment to successful on-site wastewater management, or alternatively will require in-depth investigation and incorporation of sophisticated mitigation measures in the

design to permit compliant onsite wastewater management.



5.2 LCA Conclusions and Design Implications

Qualitative LCA modelling has identified the following site constraints:

• Soil texture – adopt DIR appropriate for clay soils

• Erosion - potential for inappropriate land application designs to cause

erosion. Adopt designs with shallow subsurface irrigation through

pressure compensating lines, incorporate gypsum and bed lines in

imported topsoils.

• Climate – use water balance model

• Proximal surface waters – maintain 100m setback

• Rocky Profiles – adopt irrigation designs

Please refer to See Section 6 and Appendices for specific system

recommendations.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



6. Proposed Onsite Wastewater System Design

6.1 General System Recommendations

Given the results of the LCA, the following recommendations are made for a

suitable wastewater treatment system:

• Given the site constraints, secondary treatment of effluent with

subsurface disposal via subsurface irrigation is a suitable method for

onsite wastewater system disposal.

6.2 Onsite Wastewater Flow and Land Application Area Modelling

For modelling purposes it is proposed that a two bedroom equivalent dwelling

with provision for mains water availability will be constructed. The dwelling is

assumed to have full water savings fixtures and a design flow allowance

under EPAV 2016 of 150 L per person per day. Therefore, the calculated

effluent flows and required irrigation area is as follows:

6.2.1 Water Balance and Land Application Area Modelling

Please refer to Appendix 2 for the water balance modelling based upon VLCAF

(2013). The nominated area method is used to calculate the area required to balance all

inputs and outputs, without the need for wet weather storage. As a result of these calculations,

at least 197 m2 of area is required to achieve zero wet weather storage.

6.2.2 Nutrient Balance and Land Application Area Modelling

Please refer to Appendix 3 for the nutrient balance modelling (Nitrogen and

Phosphorus) based upon VLCAF (2013). The methodology aims to ensure that the

LAA is of sufficient size to ensure all nutrients from the applied effluent are assimilated by

soils and vegetation. As a result of these calculations, at least 149 m2 of area is required to

achieve sustainable assimilation of N and P over the nominated system design life.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



BASED UPON THE ABOVE MODELLING THE MINIMUM MODELLED LAA REQUIREMENT IS 197 m2 FOR SECONDARY TREATED EFFLUENT BASED UPON THE NUTRIENT BALANCE MODEL.

6.3 System Design

6.3.1 Treatment System

Given the above modelling the following treatment system would be

appropriate:

• Min DN100 gravity fed sewer pipe

• Min 1500L Approved Packaged Treatment Plant

OR

• Min 3000L dual purpose septic tank with outlet filter

• Min 9 m2 gravity dosed EPA endorsed sand filter

• Min 1000L pump well

• Max 0.01mm inline filter

6.3.2 Land Application Areas

The land application areas could consist of:

• Min 197 m2 of subsurface irrigation with appropriate buffer zones

6.3.3 Provision of Adequate Setback Distances

Given the minimum land application areas modelled above combined with the

current development plan, setback distances complying with the minimum

requirements of EPA Vic (2016) are achievable (see Figure 2 and Appendix 4).

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



7. Conclusions and Further Recommendations

In conclusion the following comments and recommendations are made:

• Given the site constraints, secondary treatment with subsurface disposal

is required.

• The maximum wastewater flow rate (MWWF) modelling shows that the

generated flows from the proposed 2 bedroom equivalent dwelling is

likely to be no more than 450 L/day.

• Modelled flows will likely require a land application area comprising:

• Min 197 m2 of subsurface irrigation with appropriate buffer zones)

• It is likely that peak flows associated with the modelled development

should be within the buffering capacity of proposed systems both in

terms of the system sizing as well as for their acceptance into the

disposal area.

• Given the lot size and current development plan adequate setback

distances and reserve provisions can be met.

• It is likely that earthworks and drainage installation associated with

development proposal will alter conditions of the site and as a result the

recommendations of this report MUST be reconfirmed after these works

have occurred. Failure to ensure this will void the design

recommendations. Stormwater diversion or interceptor drain installation

may be appropriate at this time. This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



• If the prescriptions of this report are followed the likely human and environmental health risks associated with effluent disposal over the site is low.

S Nielsen MEngSc CPSS Director Strata Geoscience and Environmental Pty Ltd P: 0413545358 E: [email protected] W: www.strataconsulting.com.au

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.


www.strataconsulting.com.au


8. References

• AS1726-1993- Geotechnical Site Investigations

• AS 1547-2012 Onsite Wastewater Disposal

• Bureau of Meteorology Website- Monthly Climate Statistics

• EPA (2016) Vic Code of Practice for Onsite Wastewater Management

• MAV & DSE 2006 (as amended) Model LCA Report

• VLCAF (2013) Victorian Land Capability Assessment Framework –

Calculation of Water and Nutrient Balances

• Isbell (2002) Australian Soil Classification (Revised Edn) CSIRO

Publishing

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 1 Indicative Borelog

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 2 Nutrient and Water Balance Calculations (after VLCAF 2013)

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 3 Wastewater System Design

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Irrigation Design

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Figure 1 Irrigation cross section showing major delivery/flush lines and irrigation lines.

Figure 2 Irrigation Plan View



Land Application Area Design and Construction Notes

1. Delivery/flush line diameter = 25 -30 mm 2. Irrigation line diameter = 12-16mm 3. Irrigation line spacing (A) =300 mm for Sands, Sandy Loams and Loams to 600mm for

Clay Loams, Light Clays and Heavy Clays (see the wastewater flow modelling section of this report for soil classification).

4. Dripper/Sprinkler spacing (B) as per manufacturers specifications. 5. A vacuum breaker should be installed at the highest point of the irrigation area (or in

the case of multiple irrigation lots at each lot). This breaker should be protected and marked).

6. A flush line should be installed at the lowest point of the irrigation area incorporating a return valve for back flushing of the system back into the treatment chamber.

7. All lateral lines MUST be installed parallel to the contours of the land. All minimum setbacks MUST be adhered to.

8. An inline filter must be inserted into the delivery line. 9. The first 100mm of the natural soil below the ground surface should be mechanically

tilled to aid line installation and soil permeability 10. Gypsum should be incorporated at the rate of 1kg/5m2 in dispersive soils. 11. Imported topsoil (not clay) should be applied as shown above. 12. Selected vegetation should be planted at a density of approx. 1 plant per 4m2.

Recommendation regarding suitable species is made in this report. 13. Irrigation areas greater than 400 m2 should be split into 100 m2 cells with effluent flows

switched between irrigation lots with an automatic valve system. 14. Where practical a 50% reserve area should be identified on the site to allow movement

of the irrigation area if required. 15. In areas of moderate to steep slopes (>10%) then upslope cut off drainage should be

installed to minimise shallow ground water recharge of the irrigation area from upslope. 16. All livestock and Vehicles MUST be excluded from irrigation area.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 4 Extract from EPAV 2016

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 5 Permeability Test Methodology (AS1547-2012)

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Appendix 6 Terms and Conditions Scope of WorkThese Terms and Conditions apply to any services provided to you (“the Client”) by Strata Geoscience and Environmental Pty Ltd (“Strata”). By continuing to instruct Strata to act after receiving the Terms and Conditions or by using this report and its findings for design and/or permit application processes and not objecting to any of the Terms and Conditions the Client agrees to be bound by these Terms and Conditions, and any other terms and conditions supplied by Strata from time to time at Strata’s sole and absolute discretion. The scope of the services provided to the Client by Strata is limited to the services and specified purpose agreed between Strata and the Client and set out in the correspondence to which this document is enclosed or annexed (“the Services”). Strata does not purport to advise beyond the Services.



Integrity While all reasonable care is taken reporting to the Client, Strata does not warrant that the information contained in any report is free from errors or omissions. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from errors in a report. Any report should be read in its entirety, inclusive of any summary and annexures.. Strata does not accept any responsibility where part of any report is relied upon without reference to the full report. Latter versions of any report invalidate any recommendations, assumptions, or designs contained in former reports. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever based upon the use of older versions of any report.

Project Specific Criteria Any report provided by Strata will be prepared on the basis of unique project development plans which apply only to the site that is being investigated. Reports provided by Strata do not apply to any project other than that originally specified by the Client to Strata. The Report must not be used or relied upon if any changes to the project are made. The Client should engage Strata to further advise on the effect of any change to the project. Further advice will be provided at the Client’s cost. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever where any change to the project is made without obtaining a further written report from Strata. Changes to the project may include, but are not limited to, changes to the investigated site or neighbouring sites, for instance, variation of the location of proposed building envelopes/footprints, changes to building design which may impact upon sewage treatment plant system design, specification and performance.

Interpretation

Strata is not responsible for the interpretation of site data or report findings by other parties, including parties involved in the design and construction process. The Client must seek advice from Strata about the interpretation of the site data or report.

Design/Report Recommendations

Where sewage treatment plant and/or application system designs are provided by Strata, reasonable effort will be made to minimise environmental, public health and commercial risks associated with the disposal of effluent within site boundaries with respect to relevant Australian guidelines and industry best practise at the time of investigation. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from:

(i) changes to either the project or site conditions that affect the onsite wastewater land application system’s ability to safely dispose of modelled wastewater flows; or

(ii) changes to original use of site infrastructure or changes from original modelled loadings as a result of change of use or incorrect loading information supplied by the client: or

(iii) seepage, pollution or contamination or the cost of removing, nullifying or clearing up seepage, polluting or contaminating substances; or

(iv) poor system performance where septic tanks have not been de-sludged at maximum intervals of 3 years or sewage treatment plants have not been serviced in compliance with the manufacturers recommendations; or

(v) system /component failure of any recommended system/component; or

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



(vi) poor contractor construction/installation practice; or (vii) Inferior product/component selection by installing contractor ; or (viii) any treatment plant , treatment plant component or land application area breakdown of any kind; or (ix) failure of the client to commission both interim and final inspections by the designer throughout the system

construction; or (x) the selection of inappropriate plants for irrigation areas or any increased cost associated with upkeep of

recommended plants or their replacement; or (xi) damage to any infrastructure by seepage/effluent including but not limited to foundations, walls, driveways

and pavements; or (xii) land instability, soil erosion or dispersion caused by seepage/effluent or the installation of sewage plant

infrastructure; or (xiii) Excavation difficulties given hard rock, watertables, collapsing soils or other difficult conditions; or (xiv) Dammages to underground services via excavation or system installation; or (xv) design changes requested by the Permit Authority;or (xvi) time delays associated with any of the above, or to strata or any of its representatives being able to mobilise

to site for any reason.

Furthermore Strata does not guarantee septic trench, bed or mound design life beyond 2 years from installation,. Strata does not warrant EPA sand filter designs.

Strata does not consider site contamination, unless the Client specifically instructs Strata to consider the site contamination in writing. If a request is made by the Client to consider site contamination, Strata will provide additional terms and conditions that will apply to the engagement.



(i) the Client must not use, infringe or otherwise appropriate the same other than for the purpose of the project without first obtaining the written consent of Strata; and

(ii) the Client is entitled to a royalty free licence to use the same during the life of the works comprising the project.

Digital Copies of ReportIf any report is provided to the Client in an electronic copy except directly from Strata, the Client should verify the report contents with Strata to ensure they have not been altered in any way from the original provide by Strata.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.


This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Bushfire Attack Level Rating for

Lot 3 340B Whitegate Road Glenaroua

May 2020

Important Notes:

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.







1. Introduction

Strata Geoscience and Environmental was commissioned to perform a Bushfire Attached Level (BAL) assessment for:

Client and Site Details Client Name Simon Luthi

Site Address Lot 3 340B Whitegate Road Glenaroua

Proposed Development New dwelling

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

The investigation was conducted with reference to Australian Standard AS 3959-2009

2. Results

The results of the assessment are as follows:

FDI 100

Vegetation Type GROUP B –

Woodland

Distance to Vegetation Type (m) 60 (APPROX)

Effective Slope (°) DOWNSLOPE

BAL 19*

* MUST BE RECONFIMED WHEN DEVELOPMENT PLANS ARE FINALISED AND DEVEGETATION/SITE LANDSCAPING HAS BEEN COMPLETED. FAILURE TO ENSURE THIS WILL VOID THE ABOVE RATING.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

8700

20°

5900

35°

8530

7920

Split

Hou

se R

eloc

atio

n Op

tion

3 -S

ite P

lan

Scal

e 1:

500

@A3

Sp

lit H

ouse

Rel

ocat

ion

Optio

n 4

-Site

Pla

n Sc

ale

1:50

0@A3

-

500m

m e

xcav

atio

n fro

m N

GL 2

45.8

00

-50

0mm

exc

avat

ion

from

NGL

246

.600

-

5.9

m s

etba

ck fr

om a

cces

s tra

ck

-5.

9 m

set

back

from

acc

ess

track

-

35° a

ngle

from

Tru

e No

rth

-20

° ang

le fr

om T

rue

North

NGL

243.9

50

NORT

H TR

UE

245.7

00

NGL

ENTR

Y NG

L 24

4.450

FF

L 246

.220

LIVIN

G'S W

ING

FFL 2

45.77

0 24

6.600

NG

L 24

5.800

NG

L 24

3.950

NG

L BE

DROO

MS' W

ING

TERR

ACE

FFL 2

46.52

0 FF

L 246

.220

NGL

244.1

00

ENTR

Y LIV

ING'

S WIN

G TR

UE

FFL 2

44.97

0 NG

L 24

4.800

APPROX. 2800

NORT

H TE

RRAC

E NG

L 24

5.800

BE

DROO

MS' W

ING

FFL 2

45.42

0 FF

L 245

.720

GI N

AIL

PLCD

NG

L 24

4.400

NGL

244.4

00

APPROX. 3300

NGL

245.7

50

NGL

245.3

50

GI N

AIL

PLCD

NGL

244.5

50

NGL

500mm excavation

80

FFL B

edro

om

150 gap

270 SIP

TYPI

CAL

SET-

DOW

N DE

TAIL

Sca

le 1

:50@

A3

Appendix 1 Site Plans

Appendix 2 Extracts from AS3935-2009

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.

Appendix 2 Terms and Conditions

Scope of Work These Terms and Conditions apply to any services provided to you (“the Client”) by Strata Geoscience and Environmental Pty Ltd (“Strata”). By continuing to instruct Strata to act after receiving the Terms and Conditions or by using this report and its findings for design and/or permit application processes and not objecting to any of the Terms and Conditions the Client agrees to be bound by these Terms and Conditions, and any other terms and conditions supplied by Strata from time to time at Strata’s sole and absolute discretion. The scope of the services provided to the Client by Strata is limited to the services and specified purpose agreed between Strata and the Client and set out in the correspondence to which this document is enclosed or annexed (“the Services”). Strata does not purport to advise beyond the Services.

This co

pied d

ocum

ent is

mad

e ava

ilable

for th

e sole

purpo

se

of en

ablin

g its

cons

iderat

ion & re

view as

part o

f a pl

annin

g

proce

ss un

der th

e Plan

ning a

nd Env

ironm

ent A

ct 19

87.

This do

cumen

t mus

t not

be us

ed fo

r any

purpo

se w

hich m

ay

breac

h any

copy

right.



Integrity Any report provided by Strata presents the findings of the site assessment. While all reasonable care is taken when conducting site investigations and reporting to the Client, Strata does not warrant that the information contained in any report is free from errors or omissions. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever resulting from errors in a report. Any report should be read in its entirety, inclusive of any summary and annexures. Strata does not accept any responsibility where part of any report is relied upon without reference to the full report.

Project Specific Criteria Any report provided by Strata will be prepared on the basis of unique project development plans which apply only to the site that is being investigated. Reports provided by Strata do not apply to any project other than that originally specified by the Client to Strata. The Report must not be used or relied upon if any changes to the project are made. The Client should engage Strata to further advise on the effect of any change to the project. Further advice will be provided at the Client’s cost. Strata is not liable, and accepts no responsibility, for any claim, demand, charge, loss, damage, injury or expense whatsoever where any change to the project is made without obtaining a further written report from Strata. Changes to the project may include, but are not limited to, changes to the investigated site or neighbouring sites, for instance, variation of the location of proposed building envelopes/footprints, changes to building design which may impact upon building settlement or slope stability, or changes to earthworks, including removal (site cutting) or deposition of sediments or rock from the site.



(i) the Client must not use, infringe or otherwise appropriate the same other than for the purpose of the project without first obtaining the written consent of Strata; and

(ii) the Client is entitled to a royalty free licence to use the same during the life of the works comprising the project.

Digital Copies of Report If any report is provided to the Client in an electronic copy except directly from Strata, the Client should verify the report contents with Strata to ensure they have not been altered or varied from the report provided by Strata.