TasWater - epa.tas.gov.au · GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | i Foreword The overall objective of the Environmental Management

A

TasWater Carrick STP New Discharge Pipeline and Outfall

Development Proposal Environmental Management Plan (DPEMP)

December 2014

GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | i

Foreword The overall objective of the Environmental Management and Pollution Control Act 1994 (EMPCA) is to

provide for the management of the environment and the control of pollution in Tasmania.

As outlined in the Guide to the Resource Management and Planning System (Resource Planning and

Development Commission, 2003), EMPCA defines three main activity classifications that may cause

environmental harm. These are:

Level 1: An activity/development/use which requires a permit under the Land Use Planning and

Approvals Act 1993 (LUPAA) and which may cause environmental harm (but does not include a

level 2 or 3 activity).

Level 2: An activity listed in Schedule 2 of the Act (the activity often has a stated minimum

production threshold or is called in by the Director). Most level 2 activities require a permit under

the LUPAA, although there are some that do not.

Level 3: An activity declared to be a project of State significance under the State Policies and

Projects Act 1993.

In accordance with Schedule 2 Subsection 3(a) of EMPCA, the Director of the Environment Protection

Authority has considered the proposed development and identified it as a Level 2 activity. Meander

Valley Council (MVC) has advised that a permit under LUPAA is required for a component of the

proposed development. The MVC will refer the application to the Board of the EPA in accordance with

section 25 (1) of EMPCA.

The function of the DPEMP is to provide the Board with relevant information in order to assess the

project. Such information includes details of the project, an assessment of the existing environment in,

and surrounding, the Carrick Sewage Treatment Plant (STP) site, identification of significant

environmental, social, economic and planning effects of the project; and proposed measures to

mitigate or avoid potential adverse environmental impacts. As part of this assessment process the

DPEMP is provided for public display and comment as well as review by other government agencies.

The EPA has provided Project Specific Guidelines (PSG) for the development of the DPEMP to

ensure the relevant potential impacts are considered and addressed. These guidelines are attached in

Appendix A of this document and are used in conjunction with the DPEMP General Guidelines, issued

by the EPA Board.

ii | GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413

Abbreviations Abbreviation Description

ADWF Average Dry Weather Flow

AHD Australian Height Datum

AHT Aboriginal Heritage Tasmania

AMT Accepted Modern Technology

ANZECC Australia and New Zealand Environment and Conservation Council

BGA Blue Green Algae

BOD Biochemical Oxygen Demand

CEMP Construction Environmental Management Plan

DEPHA Department of Environment, Parks, Heritage and the Arts

DPEMP Development Proposal and Environmental Management Plan

DPIPWE Department of Parks, Primary Industries, Water and Environment

DRP Draft Decommissioning and Rehabilitation Plan

EMP Environmental Management Plan

EMPCA Environmental Management and Pollution Control Act 1994

EPA Environmental Protection Agency

EPBC Act Commonwealth Environment Protection and Biodiversity Conservation Act 1999

EPN Environmental Protection Notice

GHG Greenhouse Gas

HDPE High Density Polyethylene

kL Kilolitre

LUPAA Land Use Planning and Approvals Act 1993

m2 Square Metre

mg Milligrams

ML Megalitre

MVC Meander Valley Council

NEPM National Environmental Protection Measure

NGERS National Greenhouse and Energy Reporting Scheme

NGS National Greenhouse Strategy

NMPM Noise Measurement Procedures Manual

NOI Notice of Intent

GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | iii

Abbreviation Description

NVA Natural Values Atlas

OEMP Operational Environmental Management Plan

PCAB Policy Conservation Assessment Branch

PSG Project Specific Guidelines

PEV Protected Environmental Value

SPWQM State Policy on Water Quality Management 1997

STP Sewage Treatment Plant (synonymous with Wastewater treatment plant WWTP)

TDS Total Dissolved Solids

TPC Tasmanian Planning Commission

TSP Act Tasmanian Threatened Species Protection Act 1995

WONS Weed of National Significance

WQO Water Quality Objective

WQT Water Quality Target

7Q10 Lowest 7 day average flow that occurs once every 10 years

iv | GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413

Executive Summary TasWater proposes to construct a new discharge pipeline and outfall for the Carrick sewage

treatment plant (STP) effluent.

The key aspects of TasWater’s proposal include:

Construction of a new pipeline from the STP to the Meander River to maximise the

dilution and dispersion during the periods of discharge.

Ceasing operation of the existing discharge point on the Liffey River.

Provision of an outlet valve on the pipeline capable of use by a separate effluent reuse

scheme.

The Carrick STP is approximately 1 km north east of the town of Carrick. The Carrick STP

provides sewage services to both the Carrick and Hadspen townships and services a growing

population. The nearest sensitive uses include residents between 320-400 metres from the

proposed pipeline and outlet and a downstream water user approximately 740 metres from the

proposed outfall.

The current effluent discharge is via an open channel on the Moat property to the Liffey River

which receives little to no mixing until the confluence of the Liffey and Meander Rivers.

The key issues raised in the Project Specific Guidelines (PSG), and the sections of this

document addressing these key issues, are provided below in Table 1.

Table 1 PSG Key Issues

Key Issue Section of DPEMP

1 Ambient water quality characterisation of

the receiving environment.

Ambient water quality characterisation is addressed in Section 3.7 and Section 5.

2 Potential impacts upon water quality in

the Meander River arising from the

proposed new effluent outfall.

Potential impact and management measures

for ambient water quality are outlined in

Section 4.2.4.

This DPEMP has been developed to address the PSGs and DPEMP general guidelines and is

developed in accordance with Commonwealth and State legislative requirements. In addition

the EPA Draft Water Quality objectives for the Meander River (EPA 2013) have been

considered in the preparation of this DPEMP.

The new outfall will be in the centre of the Meander River with a four port outlet compared to the

existing open drainage channel. Discharge will be controlled with a valve and a telemetry

system such that discharge to the river will occur at 10 L/s during times only when the storage

dam is full (typically May through to September). The resultant mixing zone during these

months is expected to typically be less than 1m, and up to 14.5 m in length. This mixing zone is

significantly smaller than the current mixing zone experienced in the Liffey River.

The pipeline and new outfall provides a significant improvement to management of discharge

from the existing Carrick STP by enclosing the effluent within a pipeline and improving the

mixing of effluent in the receiving water.

The development will result in short – medium term improvements to the management of

Carrick STP effluent discharge whilst a longer term solution to service the growing Hadspen

population is developed.

GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | v

Table of Contents Foreword ................................................................................................................................................... i

1. Introduction..................................................................................................................................... 1

1.1 Proposal Summary .............................................................................................................. 1

1.2 Proponent ............................................................................................................................ 1

1.3 Proposal Status .................................................................................................................... 2

1.4 Public and Stakeholder Consultation ................................................................................... 2

1.5 Legislative Context ............................................................................................................... 2

1.6 Current Environmental Management Regime ..................................................................... 3

1.7 Proposal Context ................................................................................................................. 3

2. Proposal Description ...................................................................................................................... 4

2.1 Rationale for Carrick STP New Discharge Pipeline and Outfall .......................................... 4

2.2 Proposal Overview ............................................................................................................... 4

2.3 Location and Site Plan ......................................................................................................... 4

2.4 Existing STP ........................................................................................................................ 7

2.5 Proposed New Discharge .................................................................................................. 12

2.6 Construction ....................................................................................................................... 14

2.7 Technical and Management Alternatives........................................................................... 15

2.8 Closure ............................................................................................................................... 16

3. The Existing Environment ............................................................................................................ 17

3.1 Planning Aspects ............................................................................................................... 17

3.2 Socio-economic Aspects ................................................................................................... 20

3.3 Topography and Landscape .............................................................................................. 21

3.4 Meteorology ....................................................................................................................... 21

3.5 Geology, Geomorphology and Soils .................................................................................. 27

3.6 Groundwater ...................................................................................................................... 28

3.7 Surface Water .................................................................................................................... 28

3.8 Flora ................................................................................................................................... 33

3.9 Terrestrial Fauna ................................................................................................................ 34

3.10 Pests and Diseases ........................................................................................................... 35

3.11 Natural Hazards and Processes ........................................................................................ 35

3.12 European Heritage ............................................................................................................. 35

3.13 Aboriginal Heritage ............................................................................................................ 35

4. Potential Effects and Their Management ..................................................................................... 37

4.1 Air Emissions (and Odour) ................................................................................................. 37

4.2 Liquid Waste ...................................................................................................................... 38

4.3 Groundwater ...................................................................................................................... 46

4.4 Noise Emissions ................................................................................................................ 47

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4.5 Solid and Controlled Waste Management ......................................................................... 48

4.6 Dangerous Goods .............................................................................................................. 49

4.7 Biodiversity and Natural Values ......................................................................................... 50

4.8 Greenhouse Gases and Ozone Depleting Substances ..................................................... 51

4.9 Heritage ............................................................................................................................. 52

4.10 Visual Effects ..................................................................................................................... 53

4.11 Socio-economic Issues including Land Use and Development ......................................... 53

4.12 Health and Safety Issues ................................................................................................... 54

4.13 Hazard Analysis and Risk Assessment ............................................................................. 55

4.14 Fire Risk ............................................................................................................................. 57

4.15 Infrastructure and Off-site Ancillary Facilities .................................................................... 58

4.16 Environmental Management Systems ............................................................................... 59

4.17 Cumulative and Interactive effects ..................................................................................... 60

5. Monitoring and Review ................................................................................................................. 61

5.1 Monitoring Aim and Objectives .......................................................................................... 61

5.2 Monitoring Program ........................................................................................................... 61

6. Decommissioning and Rehabilitation ........................................................................................... 68

7. Commitments ............................................................................................................................... 69

8. Conclusion.................................................................................................................................... 71

9. References ................................................................................................................................... 72

10. Assumptions ................................................................................................................................. 74

Table Index Table 1 PSG Key Issues .................................................................................................................. iv

Table 2 Carrick STP Average Daily Influent Volume ........................................................................ 9

Table 3 Carrick STP Effluent Quality compared against existing EPN Effluent Quality

Limits for Discharge to Water (2009- 2014) ....................................................................... 10

Table 4 Effluent Quality from Final Storage Dam (February to May 2012 and Nov 2013-

May 2014) .......................................................................................................................... 11

Table 5 Discharge Plan –Proposed compared to Current ..................................................................... 13

Table 6 Project and Construction Sequence .................................................................................. 14

Table 7 Climate Summary .............................................................................................................. 21

Table 8 Mean Wind Speeds (1965-1990 compared to 1990-2014) ....................................................... 24

Table 9 Carrick Monthly Rainfall ........................................................................................................... 26

Table 10 Soil Types at the Moat Property, Carrick. .......................................................................... 27

Table 11 WQOs for Identified PEVs of the Meander River at Strathbridge ...................................... 29

Table 12 Ambient Water Quality Data 2010 -2012 (downstream of Liffey River

confluence) ........................................................................................................................ 31

GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | vii

Table 13 Ambient Water Quality Data –Meander River upstream of Liffey River

Confluence –P1 ................................................................................................................. 32

Table 14 Fauna of Conservation Significance .................................................................................. 34

Table 15 Mixing Zone Extent – Low Discharge Cases ..................................................................... 40

Table 16 Mixing Zone Extent – High Discharge Cases .................................................................... 41

Table 17 Distance to cross section of relative homogeneity. ........................................................... 42

Table 18 Comparison of Strathbridge and P1 monitoring site background water quality ...................... 43

Table 19 Summary of Proposed Discharge Impacts on Receiving Waters .......................................... 44

Table 20 Sustainability Risk Assessment Summary After Mitigation ............................................... 55

Table 21 Contact Details of Relevant Emergency Authorities .......................................................... 57

Table 22 Effluent Quality Sampling Parameters ............................................................................... 62

Table 23 Water Quality Sampling Parameters ................................................................................. 64

Table 24 Commitments Table ........................................................................................................... 69

Figure Index

Figure 1 Carrick STP Locality Plan .................................................................................................... 6

Figure 2 Site Map ............................................................................................................................... 8

Figure 3 Effluent Quality -Presence of Blue Green Algae (cells/mL) plotted on Logarithmic

Scale .................................................................................................................................. 11

Figure 4 Carrick Land Use Zoning ................................................................................................... 19

Figure 5 Mean Maximum Temperature for Cressy (°C) from 1939 to 1990 .................................... 22

Figure 6 Mean Maximum Temperature for Cressy (°C) from 1999 -2014 ....................................... 23

Figure 7 Mean Minimum Temperature for Cressy (°C) from 1939 to 1990 ..................................... 23

Figure 8 Mean Minimum Temperature for Cressy (°C) from 1999 to 2014 ..................................... 23

Figure 9 Mean 9.00 am Wind Speed and Direction from Cressy Research Station (Main

Office) Weather Station 1965 to 1990 ............................................................................... 24

Figure 10 Mean 3.00 pm Wind Speed and Direction from Cressy Research Station (Main

Office) Weather Station 1965 to 1990 ............................................................................... 25

Figure 11 Mean 9am Monthly Wind Speeds 1990-2010 ........................................................................ 25

Figure 12 Mean 3pm Monthly Wind Speeds 1990-2010 ........................................................................ 26

Figure 13 Monthly Rainfall Averages for Carrick (091013) ................................................................ 27

Figure 14 Carrick Moat Property Soil Type Map ................................................................................ 28

Figure 15 Staged Approach for Implementing Contingency Plans .................................................... 56

Figure 16 Proposed Ambient Monitoring Sites .................................................................................. 66

viii | GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413

Appendices Appendix A – Project Specific Guidelines

Appendix B – Pipeline and Outfall Design

Appendix C – Groundwater Monitoring Plan

Appendix D – Groundwater Monitoring Event March 2013

Appendix E – Meander River Upstream Quality and Flows

Appendix F – Biological Monitoring Report

Appendix G – 2001 Flora Survey

Appendix H – Desktop NVA Search

Appendix I – Aboriginal Heritage Assessment Report

Appendix J – Mixing Zone Assessment

Appendix K – Blue Green Algae Prevention Control and Management Plan

Appendix L – Risk Assessment

Appendix M – Ambient Monitoring Plan

GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | 1

1. Introduction1.1 Proposal Summary

TasWater is proposing to construct a new pipeline and outfall location for the Carrick sewage treatment plant (STP) effluent. The title of the proposal is “Carrick STP New Discharge Pipeline and Outfall”.


Construction of a new pipeline from the STP to the Meander River to maximise thedilution and dispersion during the periods of discharge.


Provision of an outlet valve on the pipeline capable of use by a separate effluent reusescheme.

This Development Proposal Environmental Management Plan (DPEMP) relates to the proposed development as outlined above. Reference to STP (sewage treatment plant) throughout this document is synonymous with a “wastewater treatment works” under clause 3 (a) of Schedule 2 in EMPCA or wastewater treatment plant (WWTP).

1.2 Proponent

The proponent for the Carrick STP New Discharge Pipeline and Outfall is:

Paul Donohue

CEO’s Representative

Tasmanian Water and Sewerage Corporation Pty Ltd

Trading as TasWater

CAN 162 220 653

169 Main Road, Moonah, Tas.7009

TasWater commenced operating on 1 July, 2013 and was formed through the amalgamation of

the three Tasmanian Water and Sewerage Corporations; Cradle Mountain Water, Ben Lomond

Water and Southern Water. TasWater is responsible for providing water and wastewater and

recycled water services within Tasmania. TasWater owns and operates 110 STPs within the

state and currently has a number of single user and multiple user reuse schemes..

The proposed capital funds for the construction of the new pipeline and outfall are as follows:

2013/2014 $85,000 for investigations and approvals

2014/2015 $360,000 for the construction phase

GHD Pty Ltd (GHD) has provided environmental and planning assistance in preparing this

DPEMP on behalf of the proponent. The GHD contact for the this DPEMP is:

Susan McLeod

Senior Environmental Consultant

GHD Pty Ltd

Level 2, 102 Cameron St

Launceston TAS 7250

Phone: (03) 6332 5531

2 | GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413

There are no known legal proceedings against the proponent and they are considered capable

of meeting the financial and resource implications of the development.

1.3 Proposal Status

A Notice of Intent (NOI) was originally submitted by Ben Lomond Water (prior to the formation of

TasWater) to the EPA. In response, the Board of the EPA determined that the project would be

assessed as a Class 2B and requested the submission of a DPEMP, prepared in accordance

with DPEMP Project Specific Guidelines (PSG) and the General Guidelines for preparing a

DPEMP.

The key issues outlined in the PSG dated 3 September 2012 (Appendix A) required to be

addressed include:

Ambient water quality characterisation of the receiving environment.

Potential impacts upon water quality in the Meander River arising from the proposed new

effluent outfall.

This DPEMP addresses the PSGs issued by the EPA along with the General Guidelines for

preparing a DPEMP. The PSGs dated 3 September 2012 also identified potential impacts from

the partial reuse system as a key issue requiring addressing. This has since been confirmed by

the EPA that these issues are no longer part of the scope of this proposal (EPA correspondence

to TasWater 8th August 2014).

1.4 Public and Stakeholder Consultation

The proposal triggers the need for approval by the EPA as it is a scheduled Level 2 activity

(capacity of the sewage treatment works exceeds 100 kL per day ADWF). Accordingly,

TasWater has undertaken consultation with the EPA in relation to the proposed works.

Consultation with the wider community, downstream users and land owners neighbouring the

‘Moat’ property has been undertaken to identify any specific concerns as a result of the

proposed construction.

The underground pipeline is exempt from the provisions of LUPPA in accordance with Section

11(d) of the Water and Sewage Industry (General) Regulations 2009. The outfall does not fall

under that exemption and therefore requires a permit under LUPAA.

Consultation with Aboriginal Heritage Tasmania (AHT) has previously been undertaken in May

2001 in relation to the proposed development site and previous aboriginal heritage studies did

not identify any issues upon aboriginal heritage.

1.5 Legislative Context

The Carrick STP New Discharge Pipeline and Outfall has been classified by the EPA as a class

2b assessment. As stated above, the pipeline is exempt from the provisions of the Land Use

and Approvals Act 1993 (LUPAA) and therefore does not require approval by Meander Valley

Council (MVC). However, the outfall requires a permit under LUPAA. The level 2b assessment

process involves the preparation and submission of a DPEMP to Council for referral and

assessment by the EPA. The MVC will refer the application to the Board of the EPA in

accordance with section 25 (1) of EMPCA. The DPEMP is submitted for public comment during

the assessment process.

As the Carrick STP New Discharge Pipeline and Outfall is deemed a level 2 activity, the Board

of the EPA will assess potential environmental impacts of the project in accordance with the

Environmental Management and Pollution Control Act 1994 (EMPCA). If the Carrick STP New

Discharge Pipeline and Outfall are approved, environmental conditions will be set by the EPA.


Any conditions imposed by the EPA Board on the new outfall will be included in the land use

planning permit issued by Meander Valley Council.

In addition to the above legislative requirements under EMPCA and LUPAA, the Carrick STP

New Discharge Pipeline and Outfall will need to comply with the State Policy on Water Quality

Management (SPWQM) 1997.

1.6 Current Environmental Management Regime

The Carrick STP is regulated via EPN 8121/2. TasWater manage the STP in accordance with

the requirements of the EPN and the Carrick Wastewater Treatment Plant Manual (BLW .2012)

1.7 Proposal Context

This proposed development is a short-medium term improvement that is part of a longer term

solution for the Carrick STP servicing populations of Carrick and Hadspen.

In future years, the population of the Hadspen areas are forecast to increase. The current

medium term plan for Carrick STP involves upgrading the STP to improve effluent quality to

meet EPN limits and possibly establishing a full reuse scheme. The long term plan is to

establish a sewage treatment solution for the Carrick Hadspen future populations. This is likely

to involve separating the Carrick STP flows from Hadspen and establishing a new treatment and

reuse facility for Hadspen (GHD August 2012, GHD September 2012) and a standalone full

reuse scheme for Carrick. An indicative timeframe for this work is 5 to 10 years.

A process audit of the Carrick STP undertaken by TasWater indicates that the Carrick STP

could potentially be upgraded to comply with its EPN limits for a population of 3600

(approximately 54% increase in flow). TasWater is undertaking some upgrade works on the

Prospect STP (which uses similar technology to the Carrick STP) to consistently meet EPN

limits. Once this is completed and the performance is monitored, TasWater plan on applying

these modifications to the Carrick STP.

The volume of effluent from Carrick STP is likely to reduce significantly if Hadspen region is treated via a new STP. The combined effluent quality improvement and reduced volume would further reduce the impact on the receiving waters.


2. Proposal Description2.1 Rationale for Carrick STP New Discharge Pipeline and

Outfall

The new discharge pipeline and outfall will deliver an improvement to the quality of the existing

receiving water by improving the mixing of effluent. The new pipeline location will also enable

partial reuse of the effluent to occur by providing and offtake point for the Moat property pivot

irrigator. The availability of effluent for reuse is expected to reduce the overall volume of

effluent discharged to water and reduced pollutant loads; whilst at the same time provide an

agricultural benefit to the Moat property owner. The new pipeline and outfall development is

considered a short-medium term improvement, whilst longer term solutions for the Carrick STP

involving STP upgrade and full reuse are considered (refer to Section 2.7 for discussion of

future development opportunities).

The current Carrick STP discharge is via an open drainage channel to the Liffey River. The flow

rates in the receiving waters of the Liffey River are often very low in dry months and

consequently, mixing of effluent is less than optimum. Effluent from the Carrick STP has on a

number of occasions tested positive for blue green algae (during spring/summer) and discharge

to the Liffey has needed to be diverted. Discretionary approval from the EPA has been granted

for emergency irrigation on the Moat property to avoid discharge to the Liffey River.

The establishment of a new discharge location in the Meander River will provide a substantial

improvement in effluent mixing as the flows in the Meander River are significantly greater than

that in the Liffey River.

The proposed new pipeline provides the infrastructure for effluent to be partially reused

(irrigated) during dryer (low flow) conditions and discharge to the receiving water during wet

conditions and generally preferred higher flow conditions. The access to irrigation infrastructure

will also assist further in the management and control of blue green algae where effluent may be

irrigated on new land areas during blue green algae outbreaks. .

2.2 Proposal Overview

TasWater is proposing a new discharge pipeline and outfall for the Carrick sewage treatment

plant (STP).



Constructing a new pipeline from the Carrick STP to the Meander River to maximise the

dilution and dispersion during the periods of discharge (improving the outfall conditions

and reducing the impact on receiving waters).

Constructing a secured outfall consisting of four outlets in the middle of the Meander

River.

Provision of an outlet valve on the pipeline capable of use by a separate effluent reusescheme.

2.3 Location and Site Plan

The Carrick STP is approximately 1 kilometre north east of the town of Carrick and

approximately 200 metres off the Meander Valley Highway within an agricultural area.

The study area for the new discharge pipeline and outfall is between the existing STP

infrastructure and the Meander River.


The new pipeline location is confined to the Moat property, a 167 ha property currently owned

by J& L Mason. Other residential properties are between 320 metres and 400 metres from the

study area and are accessed from driveways off the Meander Valley Highway.

The locality plan below (Figure 1) shows the location of STP lagoons, the proposed pipeline and

outfall and the location of the Liffey and Meander Rivers.

Other details such as topographical features (drainage aspect and direction), property

boundaries and surrounding land use are also shown below on the Locality Plan.

FlowDirectionFlow

Direction

Conservation Covenant Area (NCA)

Pump Station &IrrigationTake Off

Point

Proposed Outfall

Location

Proposed Pipeline fromSTP Storage Dam to

Meander River

DownstreamUser (740m fromproposed outfall)

Public Reserves

499,554

499,554

500,554

500,554

501,554

501,554

502,554

502,554 5,401,

588

5,402,

588

5,402,

588

5,403,

588

5,403,

588

5,404,

588

5,404,

588

5,405,

588

5,405,

588

Figure 1G:\32\17413\GIS\Maps\Working\32_17413_01_Carrick_DPEMP_Site_Locality_RevB.mxd

0 100 200 300 400 50050m

©2013. Whilst every care has been taken to prepare this map, GHD (and Google and DPIPWE theLIST) make no representations or warranties about its accuracy, reliability, completeness or suitability for any particular purpose and cannot accept liability and responsibilityof any kind (whether in contract, tort or otherwise) for any expenses, losses, damages and/or costs (including indirect or consequential damage) which are or may be incurred by any party as a result of the map being inaccurate, incomplete or unsuitable in any way and for any reason.

Job NumberRevision B

32-17413

Date 07 Oct 2014

TasWaterCarrick STP DPEMP

Site Locality

Data source: Google Earth Pro, satellite imagery, 2013; DPIPWE theLIST, reserves and property boundaries, 2013; TasWater, transport segments, 2013; GHD, locations, 2012. Created by jtoregan, updated by dtickner

2 Salamanca Square Hobart TAS 7000 Australia T 61 3 6210 0600 F 61 3 6210 0601 E [email protected] W www.ghd.com

Map Projection: Transverse MercatorHorizontal Datum: GDA 1994Grid: GDA 1994 MGA Zone 55

Scale at A4 - 1:17 500

SITE

ExistingEmergency

IrrigationArea

STPStorage

Dam

Existing Outfall to Liffey River

Irrigation Area

LEGEND

STP Boundary - Title Ref 25757/1 & 137714/1

Moat Property Boundary - Title Ref 142703/1

Reserves

Irrigation Area Buffer to public access areas andsurface water (20m)

Proposed Pipeline


2.4 Existing STP

2.4.1 Existing Infrastructure

The Carrick STP services the populations of Carrick and Hadspen. The wastewater is currently

pumped from Hadspen over a rising main 4.23 kilometres to the Carrick STP. The majority of

flow (approximately 80 percent), comes from the Hadspen catchment and Hadspen has been

identified as potential growth area (GHD Sept 2012).

The current Carrick STP is a secondary treatment plant consisting of influent screening and

pumping, two 1.395 ML tandem intermittent decant extended aeration lagoons (IDEALs), sludge

drying and drying pans, a large 35 ML facultative lagoon for polishing and disinfection and a 25

ML storage dam. The primary lagoon was constructed in the 1970s and the remaining

infrastructure was constructed in 2002 when the STP was upgraded.

Following treatment, treated effluent is currently discharged to an open channel which flows into

the Liffey River. The discharge is piped for the first 250 metres from the STP after which it runs

through an open drain. The discharge into the Liffey River is approximately 600 metres from the

STP (Figure 2). This channel also drains areas of the property between the STP and the river.

Within 600 metres of the current discharge location, is the Liffey River and Meander River

confluence.

The STP operates 24 hours a day, 365 days a year and will continue to do so once the new

pipeline and outfall are constructed. .

2.4.2 Effluent Flow

The average daily flow to the Carrick STP is estimated to be between 500 and 600 KL per day

(ADWF) with flows varying significantly during winter, when infiltration is at its greatest. The

current permitted ADWF is 624 KL per day (EPN 8121/2). Average daily influent flow data for

the Carrick STP was sourced from TasWater and is summarised in Table 2 below.

Flows are lowest in summer during January and February. Flows currently to the STP vary

significantly in winter when significant infiltration is experienced (BLW, 2010). The average

annual volume of effluent in the last 5 years was 231 ML and is understood to be representative

of Carrick STP annual effluent volumes.

If the Carrick and Hadspen wastewater continues to be treated at the existing Carrick STP, the

average daily flow is expected to continue to increase from 0.6 ML/day to 1.3 ML/day by 2060

which is approximately double the current ADWF (GHD Aug 2012).

ExistingEmergency

IrrigationArea

FlowDirectionFlow

Direction

Drainage Line to Liffey River

Pump Station & Irrigation Take Off

Point

Proposed Outfall

Location

STP Storage Dam (Inside TasWater

Property)

Meander Valley Hwy


Meander River

Carrick


Liffey/MeanderRiver Confluence

Moat PropertyResidence

(500m from STPStorage Dam)

Drainage Line to Meander River

Residential Property(400m from outfall)

Residential Property(320m from STPStorage Dam)

DownstreamUser (740m fromproposed outfall)

Westwood Road

Residential Property(340m from STPStorage Dam)

Liffey

River

Meander River

Meander River

500,441

500,441

500,941

500,941

501,441

501,441

501,941

501,941

502,441

502,441 5,401,

892

5,402,

392

5,402,

392

5,402,

892

5,402,

892

5,403,

392

5,403,

392

5,403,

892

5,403,

892

5,404,

392

5,404,

392

Figure 2G:\32\17413\GIS\Maps\Working\32_17413_02_Carrick_DPEMP_Site_Plan_RevB.mxd

0 100 200 300 400 50050m

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32-17413

Date 07 Oct 2014

TasWaterCarrick STP DPEMP

Site Plan

Data source: Google Earth Pro, satellite imagery, 2013; TasWater, waterways & transport segments, 2013; DPIPWE theLIST, property boundaries, 2013; GHD, locations, 2012. Created by: jtoregan, updated by: dtickner



Scale at A4 - 1:12 500

LEGEND

Proposed PipelineExisting Drainage Line

Private Access Road

Irrigation Area Buffer to public access areas and surface water (20m)Public Road STP Boundary - Title Ref 25757/1 & 137714/1

Moat Property Boundary - Title Ref 142703/1

Irrigation Area

River


Table 2 Carrick STP Average Daily Influent Volume

Month 2013/2014

Average

Daily

Influent

Volume (kL

per day)

2012/2013

Average

Daily

Influent

Volume

(kL per

day)

2011-2012

Average

Daily Influent

Volume (kL

per day)

2010-2011

Average

Daily Influent

Volume (kL

per day)

2009-2010

Average

Daily Influent

Volume (kL

per day)

July 621 737 824 676 1202

August 1,492 694 887 843 1030

September 1,123 750 667 931 1095

October 979 623 656 636 729

November 994 569 580 604 586

December 635 486 521 597 516

January 481 474 469 476 430

February 251 318 413 534 408

March 457 471 465 600 481

April 475 450 462 635 457

May 496 495 608 544 429

June 480 438 620 855 628

Source: TasWater STP flow data AERs

2.4.3 Effluent Quality

TasWater currently conducts effluent quality monitoring as per the existing EPN requirements

(EPN 8121/2 issued 23 Sept 2011).

The treated effluent monitoring results from the STP outlet (2009-2014) are compared against

the EPN effluent emission limits in Table 3 below. Bolded figures identify which parameters

exceed the specified EPN limit for effluent quality. The Carrick STP effluent often exceeds many

of its licence discharge limits including those for BOD, suspended solids, ammonia, nitrogen,

phosphorus, pH and thermotolerant coliforms. The Carrick STP is planned for an upgrade to

meet all EPN limits, however this upgrade is not part of the proposed development in this

DPEMP.

A summary of the blue green algae effluent analysis is shown in Table 3 and Figure 3 below.

On a number of occasions the Carrick STP has detected blue green algae at levels exceeding

the EPN trigger requiring EPA notification (5,000 cells/mL). Consistent with TasWater’s BGA

Prevention and Management Control Plan, when total BGA are detected above the EPN trigger

follow up checks on the type of BGA and concentration of toxins is undertaken. The presence

of microcystin toxins have not been detected above the level of detection (< 0.2 ug/L) for Carrick

effluent.


During these periods when BGA >5,000 cells/mL, requests for approval from the EPA for

emergency irrigation of the effluent have been pursued to avoid discharge to ambient waters.

Periods of high blue green algae growth have been typically detected in months December

through to March. Management of blue green algae outbreaks is undertaken in accordance

with TasWaters Blue Green Algae Prevention Control and Management Plan (BLW 2011).

Effluent irrigation is permitted on the Moat property under emergency conditions specified in the

Carrick STP EPN 8121/2. For example between March 2012 and June 2012, 15.8 ML of

effluent was irrigated on the Moat property under these emergency conditions due to the

presence of blue green algae (Figure 3). This equated to 9 per cent of the Carrick STP’s total

annual effluent discharge.

Practices to prevent the outbreak of BGA at Carrick include:

removal of sludge to reduce the in-situ sources of N and P;

use of agitators and aeration to promote vertical mixing and to break up any thermo-

cline; and

and management of residence time in lagoons.

The EPN regulatory limits currently apply at the point of discharge from the STP lagoon.

However the proposed point of discharge following the new pipeline and outfall will be from the

effluent storage dam. Previous monitoring has only been undertaken from the effluent storage

dam during periods of high BGA counts to monitor the quality of effluent during emergency

irrigation. The available results for the effluent storage dam are shown below in Table 4. These

results are likely to be skewed towards a higher pH and suspended solids levels due to the

presence of BGA.

Table 3 Carrick STP Effluent Quality compared against existing EPN Effluent Quality Limits for Discharge to Water (2009- 2014)

Parameter Unit Existing Effluent Quality

(2009-2014)

EPN –

Effluent

Quality

Limits

Median 90th

Percentile

Maximum Maximum

BOD – total (n=60) mg/L 12.0 26.0 36 20

Suspended Solids,

TSS (n=60)

mg/L 38 64.4 180 40

Conductivity(n=31) uS/cm 445 504 549

Ammonia – N (n=60) mg/L 5.36 9.28 10 10

Total Nitrogen

(n=56)

mg/L 11.9 16.2 20.5 15

Total Phosphorus –

(n=55)

mg/L 4.53 7.29 8.29 8

Thermotolerant

coliforms (n=59)

cfu/100

mL

800 6,400 21,000 1000

Enterococci (n=62) cfu/100 454 1,970 4,200


mL

Oil and Grease

(n=50)

mg/L 2 3.1 9 10

pH (n=36) 8.1 8.97 9.7 6.5-8.5

Blue Green Algae

(n=48)

cells/mL 0 205,000 1,900,000 5,000*

Source: TasWater Carrick STP Results 2009 to 2014

Notes: Bold denotes parameters exceeding EPN limits

* Trigger for notification to the EPA

Figure 3 Effluent Quality -Presence of Blue Green Algae (cells/mL) plotted on Logarithmic Scale

Table 4 Effluent Quality from Final Storage Dam (February to May 2012 and Nov 2013-May 2014)

Parameter Unit Median Maximum

BOD (n=34) mg/L 8.15 43

Suspended Solids TSS (n=34) mg/L 22.5 470

Conductivity (n=1) uS/cm 437 484

Ammonia (n=32) mg/L 3.1 8.92

Total Nitrogen (n=35) mg/L 7.38 83.1

Total Phosphorus (n=34) mg/L 2.7 10.1

Thermotolerant coliforms (n=34) cfu/100 mL 280 8,200

Enterococci (n=31) cfu/100 mL 137 4,000

Oil and Grease (n=4) mg/L <1 <1


Parameter Unit Median Maximum

pH (n=16) 8.56 10.55

Blue Green Algae (n=31) cfu/100mL 130,000 5,400,000

n/a = results not available * requires stock withholding times

2.5 Proposed New Discharge

The proposed new discharge is in the Meander River approximately 400 metres downstream of

the Liffey River-Meander River confluence and approximately 750 metres from the outlet point

of the existing STP storage dam (refer to Figure 2). The existing discharge to the Liffey River

will be eliminated.

2.5.1 Outfall Pipeline

As part of the new discharge, a new outfall pipeline will need to be constructed to connect the

existing storage dam with the existing irrigation infrastructure and the proposed Meander River

outfall. The proposed outfall pipeline comprises:

A 0.9 to 1.8 m buried pipeline between the STP effluent storage dam and the Meander

River outfall

An off take to the Moat property irrigation infrastructure at the existing Moat property pivot

irrigator pump station.

An underwater four port outlet for the proposed Meander River outfall.

The outfall pipeline will be connected to an existing tee and valve on the STP effluent storage

dam and no modifications will be required to the existing STP piping infrastructure.

Details of the pipeline design and construction technique are provided in drawings shown in

Appendix B. The proposed pathway of the pipeline crosses a natural gas line as shown in

Drawing 32-172221-C002, Appendix B. The effluent pipeline design has been developed in

consultation with Tasmanian Gas Pipeline and in accordance with the mandatory work

procedures provide by TGP. The pipeline will pass underneath the gas pipeline allowing a

minimum space of 300 mm between the gas and effluent pipelines. A concrete barrier will be

inserted above the effluent pipeline to provide protection.

2.5.2 Outfall Design

The outfall will be anchored to the bed of the Meander River and effluent discharged via a four

port outlet to maximise mixing in the receiving water. The design of the proposed effluent outfall

pipeline is provided in Appendix B. The outfall will be fixed to the river bed with concrete anchor

blocks and will remain below the water surface at all times, including during periods of low flow,,

at an approximate average depth of 1 m. The impacts associated with the outfall design are

discussed further in Section 4.2.4.

2.5.3 Effluent Quality

The proposal does not include any changes to the STP operation and as such the effluent

quality will be similar to current effluent quality as presented in Section 2.4.3. Information on the

potential impacts relating to the new discharge point is provided in Section 4.2.4.


2.5.4 Discharge Management

The discharge of effluent from the new pipeline and outfall location is to be managed in

combination with a partial reuse scheme on the Moat property. The partial reuse scheme will be

operated by the Moat property owner and is not part of the scope of this development proposal.

Although the partial reuse scheme is not part of the scope of this proposal it is described below

to provide context to the discharge management proposed for the new pipeline and outfall.

The partial reuse scheme is expected to use approximately 99 ML effluent during the irrigation

season which will typically be between October and April. During the non-irrigation season,

treated wastewater will be stored in the existing 25 ML storage dam and be discharged to the

Meander River as required. The total volume of effluent expected to be discharged to the

Meander River in an average rainfall year is between 93 - 126 ML. An indicative program of

effluent discharge based on an average year rainfall is provided in the table below. The table

compares the proposed program of discharge (average) to the 2013/2014 year STP discharge.

Table 5 Discharge Plan –Proposed compared to Current

Month 2013/2014 Carrick STP discharge (ML)

Proposed average year STP discharge (ML)

July 19.2 27.9

Aug 46.3 28.5

Sept 33.7 25.1

Oct 30.3 Irrigation

Nov 4.9 Irrigation

Dec 8.5 Irrigation

Jan 3.4 Irrigation

Feb 0 (emergency irrigation) Irrigation

Mar 0 (emergency irrigation) Irrigation

Apr 1.9 Irrigation

May 15.4 Storage in 25 ML dam

Jun 14.4 19.2

TOTAL 178 100.7

It is anticipated that the volume of effluent to be discharged to the Meander River will be similar

to the current volumes of effluent being discharged between May and September to the open

channel that conveys the flow to the Liffey River (average over 3 years is 120 ML). Ultimately

the volume of effluent discharged to the Meander River will depend on the seasonal and crop

demand for irrigation.

Discharge management of effluent containing blue green algae will continue to be in

accordance with the existing TasWater Blue Green Algae Management plan (Appendix K).

Effluent will be discharged to the Meander River at a flow rate of 10 L/s so as to ensure there is

adequate mixing (The management of discharge and impacts on receiving waters during

different flows is further discussed in Section 4.2.4).

2.5.5 Discharge Controls, Instrumentation and Telemetry

New instrumentation will be installed to measure the depth of water in the Treated Effluent

Storage dam. Radio telemetry will also be provided sending a signal to open or close the


proposed actuated valves to control flow from the Treated Effluent Storage dam. When the

level of effluent in the storage dam is below full (135.7 AHD) the outlet valve will be closed

allowing the dam to fill. When the effluent storage dam is full, the valve will be opened to allow

discharge to the Meander River outfall.

An actuated control valve will also be on the pipeline to the Meander River Outfall. When open

this valve will allow discharge to the river at 10 L/s and when closed to prevent it. Limit switches

will be installed to report back the valve’s position to the control system.

A flow meter will be installed on the discharge end of the outfall pipeline discharging into the

Meander River. This will allow measurement of treated effluent that is being discharged into the

Meander River.

Remote alarms will be in place to detect any failure of the controls.

Further information on the pipeline and outfall design and process is provided in Appendix B.

2.5.6 Ancillary Infrastructure

Site access to the proposed outfall pipeline will be via the existing farm road during construction

and operation. Traffic volumes are not expected to change significantly from the existing

situation once the construction period has ended. Inspections of the outfall and pipework will be

required from time to time by TasWater operators.

Actuated valving at the outfall pump will require power supply off the existing power supply pole,

owned by The Moat.

There are no proposed changes to off site or ancillary infrastructure (water, stormwater,

electricity) required as part of the new discharge location.

2.6 Construction

2.6.1 Construction Sequence

The current project program is presented in Table 6 below.

Table 6 Project and Construction Sequence

Item Expected Timeframe

Prepare detailed design of new pipeline and outfall Following EPA approval

Issue of Construction tenders One month from detailed design

Construction Contract awarded One month from issue of tenders

Construction completed 3 months from contract being awarded

Commissioning of new pipeline and outfall Immediately following completion of construction

The proposed construction and commissioning activities include:

Trenching for pipe laying – required to install the outfall pipeline and outfall into theMeander River.

Commissioning of the new outfall pipeline and outfall.

Decommissioning of Liffey discharge drainage and outfall.


Appropriate environmental controls will be implemented for the construction and post-construction phases of this project. This will be detailed in the form of a CEMP. Specific impact and mitigations measures are explained in Section 4 of this DPEMP.

Construction equipment will involve standard earthworks equipment including, but not limited to, articulated dump trucks, excavators, drill rigs, water cart and light vehicles.

Construction activities will typically be undertaken 5 to 6 days per week between the hours of 7.00 am and 6.00 pm. Construction activities will not be undertaken on Sundays or on public holidays and in such a manner as not to disturb the property owner or neighbours with noise.

A contractor will be employed to install the works.

It is estimated that no more than ten (10) construction workers at any one time will be on site during the construction period.

2.6.2 Construction Technique and Materials

The outfall pipeline will be installed below ground by open trenching and will be situated at a sufficient depth to minimise potential impacts on agricultural activities (such as sub surface drainage currently on the Moat property). Typically a cover over the pipeline between 0.9 to 1.1 m is normally adopted through agricultural properties. The proposed pipeline has been designed to have a minimum cover of 0.9 m and up to 1.8 m as shown in design drawings in Appendix B.

Subject to the suitability of existing soils, embedment material around the pipeline will be sourced from the excavated material. If existing soils are not suitable conforming embedment material will be imported from a local quarry/supplier. Trench refill material will be sourced from the excavated material and reinstated to match existing soils layers.

The outfall in the Meander River will comprise polyethylene pipework (DN225 pipeline size) fixed to the base river bed via concrete anchor blocks. Refer also to Section 2.5.2.

The proposed pathway of the pipeline crosses a natural gas line as shown in Drawing 32-172221-C002, Appendix B. The construction of the effluent pipeline will be undertaken in consultation with Tasmanian Gas Pipeline (TGP) and will address all required notifications and necessary consents as required by TGP, including a joint site meeting with TGP.

2.6.3 Commissioning

At the completion of the construction of the proposed outfall pipeline and outfall to the Meander

River, a commissioning and assessment period will occur during which time it will be determined

whether the outfall pipeline and outfall is meeting the proposed requirements and mixing zone.

Section 5 provides details on the monitoring and review requirements to be undertaken during

the commissioning phase including verification of the mixing zone.

Once the outfall pipeline and outfall has been commissioned, decommissioning of the existing

Liffey discharge will occur. This will include removal of the discharge stream from this channel,

and the removal of Bulrushes growing in the channel, will improve the performance of the

channel as a natural discharge point for surrounding areas.

2.7 Technical and Management Alternatives

2.7.1 Site Alternatives

The selection of the proposed outfall site and pipeline route was made on the basis of relocating

the current discharge from the relatively low flow Liffey River to the higher flow Meander River

where more efficient dilution can be achieved. The pipeline location also allows for an offtake to

the existing Moat Property irrigation infrastructure so that treated effluent from the STP can be

partially re-used.


Only the subject site meets both these criteria and was selected on this basis.

Discussions with the owners of the Moat indicate that they would be agreeable to the proposed

location of the outfall and the outfall pipeline.

2.7.2 Design Alternatives

A single port discharge outlet on the edge of the river was considered as an alternative to the

four port outfall in the middle of the river. Mixing dilutions modelled during the mixing zone

assessment suggested that the four port discharge centrally positioned would provide the best

mixing zone and was preferable over discharge from the river edge.

2.7.3 Management and Operational Alternatives

The alternative option to a new pipeline and outfall location is to implement a full reuse scheme. The required winter storage volumes to hold a one in ten wet year event for a future full reuse scheme for the existing combined Hadspen/Carrick effluent is 154 ML. Alternatively a full reuse for 2040 Carrick only populations would require a winter storage volume of 48 ML (GHD October 2014). Additional winter storage has not been pursued as part of this proposal as it is focussed on an initial short term solution. Additional storage capacity and land for a full reuse scheme will continue to be investigated by TasWater as part of an appropriate Carrick Hadspen STP longer term solution. Should a future full reuse scheme be established, it is anticipated that the proposed new outfall would be rarely required however would continue to provide an approved emergency discharge location.

Other options considered for the future of Carrick and Hadspen sewage treatment include

directing Carrick-Hadspen wastewater to the Prospect STP (and upgrading), however this was

dismissed following an options review on the basis of economics (GHD Sept 2012).

2.8 Closure

A draft Decommissioning and Rehabilitation Plan (DRP) will be prepared within 30 days of

notifying the Director of any decision that is likely to give rise to the temporary or permanent

cessation of activity, as outlined in the existing EPN No. 8121/2 (r1) (23 September 2011).

Decommissioning and rehabilitation will be adopted for the proposed new discharge location

and for the decommissioning and rehabilitation of the existing discharge location. The proposed

new discharge is reversible following cessation of operations. Further details regarding

decommissioning and rehabilitation are provided in Section 6.


3. The Existing Environment3.1 Planning Aspects

3.1.1 Location and Associated Infrastructure

The location of the proposal site and the associated infrastructure is shown in Figure 2. Existing

infrastructure relevant to this proposal includes:

Moat Property irrigation infrastructure (pivot irrigator pump station and wet well).

Moat Property farm access track to the pivot irrigator, pump station and wet well.

TasWater STP and 25 ML winter storage dam.

Existing effluent open channel discharge and other surface water drainage lines.

The STP site is accessed directly off Meander Valley Highway, proposed irrigation area is

accessed via the Moat property and farm tracks.

3.1.2 Land Tenure and Title Details

The wastewater treatment plant site is found on the drawings ‘Certificate of Title Volume 25757

Folio 1’ and ‘Certificate of Title Volume 137714 Folio 1’ and is owned by Tasmanian Water and

Sewerage Corporation (Northern Region) Pty Ltd. The titles occupy areas of approximately 4.3

ha and 2.7 ha respectively, and are accessed via a private driveway off Meander Valley Road to

the south.

The land surrounding the STP is comprised in Certificate of Title Volume 142703 Folio 1 (“The

Moat”) and is owned by James Maxwell Mason and Norma Lynn Mason. The title occupies an

area of approximately 170 hectares and is also accessed via a private driveway off Meander

Valley Road. The property is used for agricultural purposes and contains existing irrigation

infrastructure with water drawn from the Liffey and Meander Rivers.

Property boundaries are shown in Figure 2.

It is proposed that an easement will be acquired by TasWater over the pipeline route.

3.1.3 Planning Controls and Land Zoning

The site is subject to the provisions of the Meander Valley Interim Planning Scheme 2013 (the

Scheme).

The STP is within the Utility Zone and under the Scheme (refer to Figure 4). Utilities are a

permitted use class in the zone, except where for minor utilities (local distribution or reticulation

services) which do not require a permit.

The proposal seeks to develop a new underground pipeline across the adjoining Moat property

(CT 142703/1) terminating with a new outfall into the Meander River. The Moat property is

zoned Rural Resource (refer to Figure 4). The underground pipeline is exempt from the

provisions of the Land Use Planning and Approvals Act 1993 (LUPAA) in accordance with

Section 11(d) of the Water and Sewerage Industry (General) Regulations 2009.

The outfall is not exempt under the Regulations. It is classified according to the Utilities use

class which applies to the STP, which is discretionary in the Rural Resource Zone.

The outfall also requires a discretionary permit in accordance with Clause 25(1) of the

Environmental Management and Pollution Control Act 1994.

There are a number of Codes in the Scheme which are relevant to the proposed development:


Clause E4 Road and Railway Assets Code – The code provisions do not apply because

the outfall will not alter the access arrangements associated with the STP.

Clause E6 Car Parking and Sustainable Transport Code – The code provisions do not

apply because there are no parking requirements set for the Utilities use class.

Clause E7 Scenic Management Code – The code provisions do not apply because the

proposed development will be sited more than 100 m from the Scenic management –

tourist road corridor shown on the Scheme maps (refer to Figure 4).

Clause E8 Biodiversity Code – The code provisions do not apply because the proposed

development will not be within the area of priority habitat shown on the Scheme maps

(refer to Figure 4), and does not otherwise involve removal of native vegetation. As

identified in Section 3.8 (Flora), the proposed pipeline route and outlet comprises

agricultural land (TAS VEG Classification FAG) whilst the riparian vegetation isdominated by introduced species such as Salix X Rubens (crack willow). In any event,

the Code deals with an issue which falls within the ambit of the EPA’s assessment under

EMPCA.

Clause E9 Water Quality Code – The code provisions are applicable however are not

relevant to Council’s assessment because they deal with an issue which falls within the

ambit of the EPA’s assessment under EMPCA.

It is noted that the new outfall will replace an existing discharge from the wastewater

treatment plant which occurs into the Liffey River. Given that Meander River experiences

higher flow rates, the new outfall will provide a substantial improvement in effluent

mixing.

Clause E11 Environmental Impacts and Attenuation Code – Clause E11.4.1 provides a

specific exemption where a use or development is for a Level 2 Activity assessed by the

EPA under EMPCA. It is noted Table 11.2 of the Code prescribes attenuation distances

for sewage treatment plans which are dependent upon the type of installation and design

capacity (dry weather flow).


Figure 4 Carrick Land Use Zoning

Source: List Map www.thelist.tas.gov.au accessed 26/09/2014


3.1.4 Land Use History

The STP has been in operation since the 1970s and the Moat property has been used for

agriculture and residential use for more than 100 years.

3.1.5 Surrounding Land Uses and Sensitive Uses

The surrounding land on the Moat property (CT 142703/1) is clear of any significant standing

vegetation and is used for agriculture. A number of other residential and agricultural properties

are within a 1 km radius of the project development footprint along Simmons St, the Meander

Valley Highway and Westwood Road. Other land uses within proximity to the STP and proposed

development footprint include the Meander Valley Highway, the Carrick training tracks,

sportsground and racecourse 250 m west from the STP.

Figure 2 shows that the nearest residents to the development site are the Moat residence

(approximately 500 metres from the STP and proposed pipeline), two properties 320 and 340

metres respectively to the south east of the STP area and a property approximately 400 metres

to the North East proposed outfall in the Meander River.

3.1.6 Conservation Areas, Wilderness and Reserves

A search of the LIST database has revealed the following reserves within approximately 1

kilometre of the development footprint area:

Public Land Classification – Public Reserve (Crown Land Act) public land west of the

development footprint area alongside the Liffey River. The reserve follows sections of the

Liffey River north west to south west of the footprint area in 3 separate locations.

Conservation Covenant – Conservation Convent (Nature Conservation Act) area south

west of the development footprint area.

Of the reserves listed above, the Public Reserve to the west of the development footprint area is

approximately 500 metres from the site area whilst the Conservation Covenant is approximately

1 kilometre from the footprint area.

The Natural Values Atlas identified no Geoconservation areas within 2 kilometres of the site

area.

3.2 Socio-economic Aspects

Carrick is a small township (population approximately 440) within the Meander Valley municipal

area, . Carrick lies on the Meander Valley Highway between Hadspen and Hagley, 17

kilometres from Launceston.

Carrick today is largely a residential settlement for a portion of the population commuting to

work in Launceston and for those who work in rural areas surrounding the town.

The median age of people in Carrick (State Suburb) was 43 years. Children aged 0 to 14 years

made up 18.5 percent of the population and people aged 65 years and over made up 13.3

percent of the population (ABS 2013).

During 2011, 58.7 percent of persons in the labour force in Carrick were employed full time,

32.3 percent were employed part time and 4.3 percent were unemployed. The most common

industries of employment within Carrick (State Suburbs) included Managers 20.2 percent,

Professionals 15.3 percent, Clerical and Administrative Workers 15.3 percent, Technicians and

Trades Workers 11.8 percent, and Community and Personal Service Workers 11.1 percent.

(ABS 2013).


3.3 Topography and Landscape

The Carrick STP comprises an area of approximately 4.2 hectares on the northern side of

Meander Valley Road. The Moat property is at an altitude of about 135 metres Australian

Height Datum (AHD) on a broad river terrace and with a very low slope of about 0.5 degrees to

the NE (Sloane Geoscience, 2012).

The Carrick STP sits at the base of a slope which defines the north east edge of a higher

terrace level at an altitude of about 145 metres AHD (Sloane Geoscience, 2009). Surface

drainage in the vicinity is influenced by an excavated drainage channel which drains to the

Liffey River about 800 metres to the north west (the current effluent discharge pathway) and a

surface drainage line running in north east direction draining to the Meander River.

The proposed pipeline will traverse the broad river terrace from the existing STP to the Meander

River.

3.4 Meteorology

The most representative meteorological station for the Moat Property with long term records for

temperature, wind and evaporation is at Cressy Research Station and is approximately 23.9

kilometres from Carrick. Rainfall data is available from Carrick BOM station 091013 and

includes the years 1907-1996 (data is recorded up to 2000, however is incomplete between

1996 and 2000).

Data for the Cressy Research Station (BoM ID: 091022) is available from 1940 till 1990. A new

Cressy Research Station (091306) commenced monitoring from 1999 and has records of wind

and temperature but does not include evaporation. The wind and temperature records from the

new Cressy station cover a smaller 11-15 year time period and are believed to be less

representative of general climatic conditions than the old station (1940/1965-1990).

Table 7 below shows a summary of the most representative long term (>25 year) climate data

for the Carrick site. This comprises Cressy BoM ID: 091022 temperature, wind and evaporation

data and rainfall data from Carrick BOM ID 091013.

Table 7 Climate Summary

BOM station &

years

Climate Parameter Climate Average

Cressy 091022

(1940-1990)

Mean Maximum Temperature (hottest month) 23.6°C (January and

February)

Annual Mean Maximum Temperature 17.2°C

Mean Minimum Temperature (coolest month) 0.9°C (July)

Annual Mean Minimum Temperature) 5.2°C

Carrick 091013,

(1907-1996)

Mean Annual Rainfall 715.4 mm

Mean Monthly Rainfall 59.6 mm

90th Percentile Wet Year – annual rainfall 917 mm

90th Percentile Wet Year – mean monthly rainfall 103 mm

Cressy 091022

(1965-1990)

Average Evaporation – annual (Cressy 091022) 1111.3 mm

Mean 9am wind speed and direction 6.4 km/hr NW


Mean 3pm wind speed and direction 11 km/hr NW

Source: BOM: 01/10/14

3.4.1 Temperature

The climate of Cressy is generally warm from November to March over spring and summer with

mean maximum temperatures ranging from 18.9°C to 23.6°C. From April to October the mean

maximum temperature ranges from 10.9°C to 17.5°C. A comparison of mean maximum

temperatures (1939-1990 Figure 5) to (1999-2014 Figure 6) suggests that temperatures have

remained consistent between these two time periods.

Figure 5 Mean Maximum Temperature for Cressy (°C) from 1939 to 1990


Figure 6 Mean Maximum Temperature for Cressy (°C) from 1999 -2014

Figure 7 Mean Minimum Temperature for Cressy (°C) from 1939 to 1990

Figure 8 Mean Minimum Temperature for Cressy (°C) from 1999 to 2014

3.4.2 Wind

Wind speed data collected at the Cressy Research Station (091022 and 091306) at 9.00 am

and 3.00 pm indicate that prevailing winds are north-westerly. Wind data from Launceston was

considered also. All sets of available information indicate that prevailing winds were north-

westerly. 1965-1990 wind data from station 091022 is shown below in Figure 9 and Figure 10.


The more recent Cressy Research Station monitoring site (091306) shows that wind speeds

between 1999 and 2010 over the recent 11 year period have been higher than the preceding 25

year period. It cannot be determined if this is due to a trend or simply due to the different data

group sizes.

Table 8 Mean Wind Speeds (1965-1990 compared to 1990-2014)

BOM 091022 (1965-1990) BOM 091306 (1999-2010)

Mean wind speed 9am 6.4 km/hr 11 km/hr

Mean wind speed 3pm 11 km/hr 20.6 km/hr

Wind speeds vary at different times of the year with the highest wind speeds generally being

observed in warmer months of the year (September through to February) as seen below in

Figure 11 and Figure 12

Source: BOM, 6/12/2013

Figure 9 Mean 9.00 am Wind Speed and Direction from Cressy Research Station (Main Office) Weather Station 1965 to 1990


Source: BOM, 6/12/2013

Figure 10 Mean 3.00 pm Wind Speed and Direction from Cressy Research Station (Main Office) Weather Station 1965 to 1990

Figure 11 Mean 9am Monthly Wind Speeds 1990-2010


Figure 12 Mean 3pm Monthly Wind Speeds 1990-2010

3.4.3 Rainfall

The average annual rainfall for Carrick is 77.08 mm. Average monthly rainfall is variable slightly

between seasons with July, followed by August being the wettest months of the year. January

and February are the driest months with an average annual rainfall of 40.6 and 38.5 mm. The

90th percentile wet year annual rainfall is 917 mm.

Table 9 Carrick Monthly Rainfall

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Mean Rainfall

40.6 38.5 43.4 55.9 68.0 68.4 83.9 79.6 65.5 65.0 51.4 55.2

% of total

5.7% 5.4% 6.1% 7.8% 9.5% 9.6% 11.7% 11.1% 9.2% 9.1% 7.2% 7.7%

Wet Year Rainfall

72.0 79.7 81.1 104.9 108.3 118.6 130.5 123.7 107.8 114.2 87.4 103.7


Figure 13 below shows the long term average monthly rainfall measured at Carrick

Figure 13 Monthly Rainfall Averages for Carrick (091013)

3.5 Geology, Geomorphology and Soils

Geology and Soils

The proposed pipeline route is along alluvial terraces leading down to the Meander River. A soil

survey of the site area was carried out in May 2001 by Serve Ag, in December 2009 by AK

Consulting and again in January 2013. The soils (AK Consulting, 2009) are summarised below

in Table 10 and shown in Figure 14.

Table 10 Soil Types at the Moat Property, Carrick.

Soil Type Description

Brumby Association Soils of the floodplain; generally sandy loam surface with lighter

coloured sub surface fine sand with tough clay at 40 cm.

Canola Association Soils on the current flood plain, commonly at lower elevation

than Brumby soils. Generally black or very dark coloured

organic and cracking clay to the surface.

Brickendon Association Soils at slightly higher elevation characterised by the presence

of quartz gravels. Surface texture is usually sandy with mottled

clay sub soil at about 45 cm.

0

10

20

30

40

50

60

70

80

90

J F M A M J J A S O N D

Rainfall (m

m)

Month

Carrick Mean Rainfall (mm)


Source: AK Consulting 2009

Figure 14 Carrick Moat Property Soil Type Map

3.6 Groundwater

Information on the current status of groundwater is provided in Sloane Geoscience Pty Ltd 2012

Groundwater Monitoring Plan for the Carrick Recycled Water Scheme (Appendix C) and

Groundwater Monitoring Event March 2013 (Appendix D). In February 2013, five new

groundwater bores were drilled in the vicinity of the project on the Moat property and water

quality monitoring undertaken in March 2013 Results of the water quality assessment are

provided in Appendix D.

In the vicinity of the STP and the foot of the escarpment slope below the travelling irrigator area

groundwater depths range from about 4.6 to 6.8 metres below ground level. Groundwater levels

in the Liffey River and Meander Rivers areas appear to be at about 3.0 to 3.5 metres below

ground level.

The SPWQM 1997 assigns drinking water as a protected environmental value (PEV) where the

groundwater salinity is less than 1000 mg/L TDS. Other PEVs considered for groundwater in

this area are irrigation and stock drinking. ANZECC aquatic ecosystem guideline levels

(ANZECC 2000) have been regarded as applicable for groundwater sites close to the surface

water features (drainage lines and rivers) including CAGW5-CAGW8 located within 30 to 70

metres of the Liffey and Meander Rivers.

3.7 Surface Water

3.7.1 Protected Environmental Values

For all surface waters within private land (including forest on private land), the PEVs of the

Meander River Catchment state that:

“…as a minimum, water quality management strategies should provide water of a physical and chemical nature to support a modified, but healthy aquatic ecosystem from which edible fish may be harvested; that is acceptable for irrigation and stock watering purposes; and which will allow people to safely engage in primary and secondary contact


recreation activities such as swimming (Deloraine, Egmont and Bracknell), paddling or fishing in aesthetically pleasing waters; and is suitable for use by Pivot and (following impoundment) in the Trevallyn Power Scheme.” (DPIWE 2004).

Specifically, the PEVs relevant to Carrick STP discharge point and downstream users include:

A: Protection of Aquatic Ecosystems:

(i) Protection of modified (not pristine) ecosystems from which edible fish are harvested.

B: Recreational Water Quality & Aesthetics:

(i) Primary contact water quality (Deloraine, Egmont [Birralee Road] and Bracknell).

(ii) Secondary contact water quality.

(iii) Aesthetic water quality.

C: Drinking Water Quality:

D: Agricultural Water Uses:

(i) Irrigation.

(ii) Stock watering.

E: Industrial Water Supply (Hydro-Electric Power Generation, Pivot)

Note: The PEVs chosen from the SPWQM are those values and uses that are currently in

evidence.

The Moat Centre Pivot extracts irrigation water from the Meander River. Existing surface drains

as shown in Figure 2, currently take excess runoff from the Moat property area and drain to

either the Liffey or Meander Rivers.

Currently the Moat property also runs a small domestic garden pump that draws water from the

Meander River (via the irrigation pump wet well). The small domestic garden pump is used for

watering lawns, flower beds and vegetable gardens at the Moat residence.

The next closest known downstream use of water (for irrigation and stock watering) is

understood to be from an off-take from the Meander River close to Westwood Road Bridge,

approximately 740 metres downstream from the proposed outfall as shown on Figure 2.

3.7.2 Water Quality Criteria

Part 3, Section 9 of the SPWQM states that Water Quality Objectives (WQOs) for a specific

body of water are to be the most stringent set of water quality guidelines which should be met to

achieve all of the PEVs nominated for the body of water. These WQOs do not set regulatory

limits. These WQOs are used as a measure of success required by part of the SPWQM for the

management of point and diffuse source pollution.

The EPA, have provided draft WQOs for the key indicators to achieve PEVs for the Meander

River at Strathbridge, (approximately 10 kilometres upstream from the proposed outfall). The

WQOs are shown below in Table 11.

Table 11 WQOs for Identified PEVs of the Meander River at Strathbridge

Parameters Proposed

Annual

WQOs

Proposed

Autumn

WQOs

Proposed

Winter

WQOs

Proposed

Spring

WQOs

Proposed

Summer

WQOs

Dissolved Oxygen

(% Saturation)

101.5% 96.5% 106.9% 100.8% 90.4%


Parameters Proposed

Annual

WQOs

Proposed

Autumn

WQOs

Proposed

Winter

WQOs

Proposed

Spring

WQOs

Proposed

Summer

WQOs

Temperature

(Celsius)

19.5 16.3 18.4 21

pH 7.5 7.6 7.1 7.5 7.4

Salinity (s/cm) 117.8 90.3 93.8 107.3 142

Turbidity (NTU) 5.3 3.2 8.6 4.8 2.8

Dissolved

Phosphorus (mg/L)

0.004 0.003 0.005 0.003 0.003

Total Phosphorus

(mg/L)

0.02 0.016 0.022 0.023 0.017

Total Nitrogen

(mg/L)

0.511 0.315 0.650 0.468 0.373

Nitrate (mg/L) 0.146 0.07 0.356 0.132 0.012

Nitrite (mg/L) 0.003 0.002 0.003 0.003 0.001

Ammonia (mg/L) 0.016 0.012 0.016 0.017 0.015

Source: EPA Draft Water Quality Objectives Meander River at Strathbridge


3.7.3 Meander River Ambient Water Quality

TasWater undertook ambient monitoring on the Meander River downstream of the confluence of the Liffey River (approximately 500 meters) within the vicinity of the proposed discharge point, on a monthly basis from 2010 to 2012. Monthly monitoring includes suspended solids, BOD, thermotolerant coliforms and enterococci. Other parameter were analysed on a less frequent basis. A summary of the data obtained from the 2010-2012 ambient monitoring is provided in Table 12 below. Although the data shown in Table 12 is upstream of the proposed new outfall location, it is downstream of the existing outfall and such there is no value in this data for establishing site specific background water quality targets (WQTs).

Table 12 Ambient Water Quality Data 2010 -2012 (downstream of Liffey River confluence)

Parameter (Units) Number of samples 80th Percentile Ambient

Water Quality

pH 6 7.8 (20th percentile)-8.4

Temperature 6 9.2 (20th percentile)-18.5

Conductivity (uS/cm) 8 72

Dissolved Oxygen (mg/L) 6 11.02

Biochemical Oxygen Demand (BOD,

mg/L)

22 2

Suspended Solids (mg/L) 22 11

Ammonia- Nitrogen (mg/L) 6 0.05*

Nitrate-Nitrogen (mg/L) 6 0.183

Nitrite-Nitrogen (mg/L) 6 0.005

Total Nitrogen (mg/L) 6 0.41

Total Phosphorus (mg/L) 6 0.05*

Oil and Grease (mg/L) 6 2

Thermotolerant Coliforms (cfu/100 mL) 20 316

Enterococci (cfu/100 mL) 22 324

*derived on the basis of the analytical limit of reporting (LOR)

Sample numbers reflect laboratory analysis results as provided by TasWater.

From March 2013, TasWater commenced ambient water quality monitoring of a site

immediately upstream of the Liffey River confluence. This site is represents background

(upstream of effluent discharge) for use in establishing site specific WQTs. At the time of

preparing this report however, only 8 analysis results were available which is not sufficient to

establish site specific WQTs. A summary of these results are presented in Table 13 below and

raw data provided in Appendix E.

Section 5.2.3 outlines the existing ambient monitoring program which will continue to capture data from this upstream site with the objective of establishing site specific WQTs (refer to Section 5.2).


Table 13 Ambient Water Quality Data –Meander River upstream of Liffey River Confluence –P1

Parameter (Units) Number of

samples

80th Percentile Ambient Water Quality

pH 7 6.4 -7.5 (20th % ile -80th % ile)

Temperature (°C) 7 10.54 -22.3(20th % ile -80th % ile)

Conductivity (uS/cm) 6 72.2

Dissolved Oxygen (mg/L) 7 9.8

Biochemical Oxygen Demand (BOD,

mg/L)

1 2

Suspended Solids (mg/L) 8 3.2

Ammonia- Nitrogen (mg/L) 8 0.0068

Nitrate-Nitrogen (mg/L) 8 0.219

Nitrite-Nitrogen (mg/L) 8 0.002

Total Nitrogen (mg/L) 8 0.438

Total Phosphorus (mg/L) 8 0.026

Dissolved Reactive Phosphorus

(mg/L)

8 0.008

Thermotolerant Coliforms (cfu/100

mL)

8 316

Enterococci (cfu/100 mL) 8 122

Blue Green Algae (cells/mL) 8 472

Chlorophyll (ug/L) 8 3.5

3.7.4 River Flow Regime

The seasonal flow regime of the Meander River at the proposed discharge point has been estimated by combining the flow data from Meander River (upstream at Strathbridge, station 852) and the Liffey River (station 164). A summary of this data is provided in Appendix E.

This data shows that on average flow rates are substantially higher in winter and spring than in summer and autumn. It also indicates that the addition of the Meander dam upstream in the catchment has the expected impact making the low flows higher and high flows lower. This effect is more pronounced in summer and autumn.

The seasonal river flow regime is required to model the likely impact of effluent discharge at different times of the year. This has been undertaken and is provided in Appendix J.

3.7.5 Surface Water Aquatic Ecology

A desktop study and a baseline biological survey of the proposed receiving environment were completed and are presented in Appendix F as part of biological monitoring undertaken in


spring 2012. Surveys were undertaken in accordance with Tasmanian AUSRIVAS Sampling and Processing Manual (2003).

In general the riparian vegetation was reduced and dominated by exotic species (Willows and blackberry). Many areas of the bank have been cleared for agricultural use.

The baseline biological survey indicated that the Meander River at the proposed outfall area is a modified environment with the invertebrate (SIGNAL 2) assessment indicating that the water quality is likely to be impacted by habitat degradation, reduced riparian condition and hydraulic manipulation. Sites monitored showed high levels of diversity of macroinvertbrate fauna and the overall diversity and abundance was consistent. The SIGNAL 2 analyses indicated that the proposed discharge is not entering a ‘pristine’ aquatic environment where the potential impact of discharge would be more severe as a result. As such the aquatic communities within the immediate downstream environment are likely to be somewhat resilient to effects of the proposed discharge.

The consistency of the upstream and downstream macroinvertebrate communities provides a solid basis for the future monitoring of the proposed discharge. This study clearly indicates that there is no distinct evidence of a pre-existing point source impact in the vicinity of the proposed discharge that may confuse the determination of discharge-based impacts.

No listed species were identified during the course of the biological monitoring.

The desktop assessment found that although the EPBC protected matter search tool identified the site area as containing potential habitat for Australian Grayling, Swan galaxias and the Green and Gold Frog, there are no recorded observations of these aquatic fauna species within either the 500 m or 5000 m buffer (refer to Appendix H ) of the proposed discharge site.

The Natural Values Atlas returned one record of Tasmanian Threatened Species Act (TSPA) listed rare flora species Vallisneria australis (water ribbon) within the 500 m buffer of the proposed discharge point. This species has been recorded downstream at the Westbury Rd Bridge in 2009.

Fish surveys following consultation with EPA (23 January 2013) were not undertaken, due to the observation during biological monitoring that no suitable habitat for the endangered, threatened or vulnerable species existed.

3.8 Flora

The flora at the Moat property has been subject to a survey assessment in May 2001 by AJ

North and Associates (refer to Appendix G). A follow up desktop assessment accessing the

Natural Values Atlas (NVA) was undertaken in 2013 to identify threatened species and

communities (Appendix H). No further survey work was required as confirmed during

consultation with the EPA on 23 January 2013.

The proposed pipeline route and outlet falls within existing agricultural land (TAS VEG

Classification FAG) and contains no threatened communities. The riparian vegetation

encountered along the Liffey and Meander Rivers at the Moat consists of vegetation dominated

by introduced species such as Salix X Rubens (crack willow).The Moat property was identified

during the 2001 survey as having 17 native and 17 introduced plant species on the Moat. A

small <2 hectare remnant of Tussock Grassland on the floodplain was identified (but not

mapped) in 2001 outside, along the Meander River in the north east of the property adjacent to

the outlet location. . The grassland vegetation in the 2001 report was described as largely

native but with numerous introduced species. Since the 2001 survey there has been significant

removal of crack willow from the property.

There were no species of national significance observed during the 2001 survey and no suitable

habitat existed. The 2013 desktop assessment (Appendix H) identified no suitable habitat for


flora of state or national significance within 500 metres of the site. Suitable habitat within 5

kilometres and observations are provided in Appendix H.

3.9 Terrestrial Fauna

The Moat property was assessed for fauna habitat as part of the 2001 flora survey (AJ North

and Associates 2001). In addition a desktop assessment of NVA and EPBC databases was

undertaken in 2013 (GHD October 2014).

The desktop investigation revealed a number of threatened fauna previously recorded or

predicted to occur within 500m and 5km of the study site. The field survey however, concluded

that the site was dominated by exotic vegetation with only small patches of relatively low quality

remnant native habitat of limited value for threatened fauna species.

Table 14 shows the vulnerable, rare or endangered terrestrial species recorded observations

and potential habitat mapped within 500 metres of the study area. As concluded in the 2001

ecology report, the Moat property is dominated by exotic vegetation with the few remnants of

native vegetation severely degraded. On this basis there is considered to be very low risk of

impact to identified threatened fauna.

Table 14 Fauna of Conservation Significance

Species Conservation Status Likelihood of Occurrence

green lined ground beetle

Catadromus lacordairei

Vulnerable (State) Species occurs within open grassy

woodland associated with wetlands.

There is potential habitat within the

region but the site itself does not

provide optimal habitat for the species

and likelihood of occurrence is low.

eastern barred bandicoot Perameles gunnii

Vulnerable

(Commonwealth)

The Eastern barred bandicoot may

occur within the study area but the site

does not provide its preferred mosaic

habitat of remnant native forest and

pasture.

Spotted tailed quoll

Dasyurus maculatus

Vulnerable

(Commonwealth) Rare

(State

The site provides marginal foraging and

no suitable denning habitat.

Tussock skink Pseudemoia pagenstecheri

Vulnerable (State) There is a small area of degraded

tussock grassland adjacent to but

outside of the irrigation area, which may

provide marginal habitat for this

species.

Grey goshawk

Accipter novaeholladiae

Endangered (State) No suitable habitat on site, according to

the 2001 ecology report.

Tasmanian devil

Sarcophilus harrisii

Endangered (State

and Commonwealth)

The site provides marginal foraging and

no suitable denning habitat.

Wedge tailed eagle Aquila audax fleayi

Endangered (State

and Commonwealth)

No suitable habitat on site, according to

the 2001 ecology report




green lined ground beetle Catadromus lacordairei

Vulnerable (State) Species occurs within open grassy

woodland associated with wetlands.

There is potential habitat within the

region but the site itself does not

provide optimal habitat for the species

and likelihood of occurrence is low.

eastern barred bandicoot

Perameles gunnii

Vulnerable

(Commonwealth)

The Eastern barred bandicoot may

occur within the study area but the site

does not provide its preferred mosaic

habitat of remnant native forest and

pasture.

3.10 Pests and Diseases

A number of woody exotic species were identified as being present at the site during the 2001 flora survey and the 2013 desktop search (refer to Appendix G and Appendix H). Several are considered environmental weeds due to their capacity to invade native bushland and have an adverse impact upon native flora. Others are recognised as agricultural weeds as they have a recognised economic impact.

The weed species were identified as Ulex europaeus (gorse), Salix X rubens (willow) and Rubus fruticosus (blackberry).

3.11 Natural Hazards and Processes

The proposed pipeline and outfall site are in a very flat area adjacent to the confluence of the Liffey and Meander Rivers. Portions of the area immediately adjacent to the river are prone to flooding. Flood areas identified by the Meander Valley Interim Planning Scheme 2013 in Figure 4. The flood areas lie particularly around the north east boundary of the Liffey River.

The site area for the new discharge pipeline is unlikely to be vulnerable to natural fires as it is

located in in an open grassy area of agricultural land with the Liffey River to south west to north

western side and the Meander River on the eastern side of the study area.

The site is very flat and as such there have been no known landslips at the study site.

3.12 European Heritage

A cultural archaeological survey was carried out in May 2001 (CEE Consulting 2002) by an

archaeological consultant Ms J Becker. The aim of the survey was to identify areas of cultural

heritage value within or adjacent to the proposed development site and to recommend

preservation methods for these areas if appropriate. The site was surveyed on foot with the

agricultural land providing good visibility. No sites of archaeological value pertaining to either

historic or prehistoric sites were located during the survey process. The proposed development

site has been largely cleared for agriculture and cropping. The highly disturbed nature of the

land made identification of sites difficult and it is likely that any artefacts were concealed or

destroyed during these processes.

3.13 Aboriginal Heritage

An Aboriginal Cultural Heritage Survey was undertaken by Rocky Sainty in May 2001 for the

Moat Property and is provided in Appendix I.


It is not anticipated that the status will have changed between 2001 and 2013, given the site

area is the same and the long term use of the area for agricultural purposes, the 2001 survey

findings are assumed to remain representative for this proposed development.

No Aboriginal sites were identified on the within the study area during this study and accordingly

Aboriginal Heritage Tasmania (AHT) had no objection to the development proceeding.

Confirmation of this position was received by GHD from AHT in October 2013.


4. Potential Effects and Their Management4.1 Air Emissions (and Odour)

4.1.1 Legislative, Policy and Performance Requirements

The Tasmanian Environmental Protection Policy (Air Quality) 2004 (Air Quality EPP) provides a

framework for the management and regulation of both point and diffuse sources of emissions to

air, and for pollutants with the potential to cause environmental harm. This Environment

Protection Policy is made pursuant to the provisions of Section 96A-96O of EMPCA 1994.

The environmental values to be protected under this Policy are:

The life, health and well-being of humans at present and in the future.

The life, health and well-being of other forms of life, including the present and future

health, wellbeing and integrity of ecosystems and ecological processes.

Visual amenity.

The useful life and aesthetic appearance of buildings, structures, property and materials.

The key performance requirements relate to maintenance of air quality during the construction

and operational phases to minimise potential impacts to site workers, local residents and the

environment.

In addition to these general requirements, the current Carrick STP EPN (8121/2(r1)) sets out the

requirement that:

Odorous gases arising from the activity must be managed so that they do not cause

environmental nuisance beyond the boundary of The Land.

4.1.2 Existing Conditions

There are no significant air emissions associated with the existing STP and effluent discharge.

All process equipment is electrically powered, therefore having no direct fuel related emissions.

There is potential for odour from the STP inlet however there has been no reported odour

incidents in the last three years from the STP or emergency irrigation and there is no evidence

of odour issues with the existing drainage discharge channel.

4.1.3 Construction Impacts and Mitigation

During construction, the potential air emissions relate to dust generation, vehicle and machinery

emissions.

All vehicles used during construction will be appropriately maintained such that vehicular

emissions are kept to a minimum during construction. Furthermore construction impacts will be

managed by a buffer zone of 320 metres that exists between the construction activity and the

nearest dwelling. The presence of this zone will ensure construction impacts to have minimal

impact on nearby public or neighbouring residents.

With the above described control measures in place during the construction phase, air impacts

(including dust and odour) are considered to be limited.

4.1.4 Operational Impacts and Mitigation

Vehicle movements associated with the operation of the proposed new pipeline and pump

station, in comparison to existing operations, will be negligible.

Given the effluent discharge will go from an open drain to an enclosed underground pipeline

with mixing of effluent in ambient waters there are not likely to be any adverse odour impacts.


4.2 Liquid Waste


The key policy document describing the management of liquid waste is the State Policy on

Water Quality Management 1997 (SPWQM 1997). The purpose of this policy is to achieve

sustainable management of Tasmania’s surface water and groundwater resources by protecting

or enhancing their qualities while allowing for sustainable development in accordance with the

objectives of Tasmania’s Resource Management and Planning System (RMPS).

Management of surface and groundwater resources focuses on the management of water

quality to achieve WQOs and maintain PEVs, with particular emphasis on pollutants. Pollutants

discharged into waterways should be reduced as far as is reasonable and practicable, by the

use of best practice environmental management and the waste management hierarchy.

The SPWQM 1997 stipulates that if it is not reasonable or practical to reduce the levels of

pollutants in the wastewater to a level which would be required to achieve the WQOs for the

receiving waters at the point of discharge, the Board (EPA) may designate a mixing zone

around the point of discharge. Where a mixing zone has been designated, emission limits must

be set at levels which will not prejudice the achievement of WQOs at or beyond the edge of the

mixing zone.


Information on the current effluent flows and quality, receiving water flows and quality and

proposed water quality objectives have been provided in Section 2.4 and 3.7.

Risks associated with blue green algae from existing effluent are currently managed by a Blue

Green Algae Prevention Control and Management Plan, Dec 2011 (Appendix K).


Potential Impacts

Construction of the new pipeline and new discharge outlet will involve some disturbance to the

farming area, river bank and bed at the proposed outfall. The location of the proposed new

pipeline and outfall are shown in the design drawings for the proposal shown in Appendix B.

The construction will involve trenching for pipe laying and anchoring of the pipeline to the centre

of the Meander River bed using concrete blocks. Construction equipment will involve standard

earthworks equipment including, but not limited to, articulated dump trucks, excavators, drill rigs,

water cart and light vehicles.

Possible impacts to surface waters during the pipeline construction phase include erosion and

runoff of sediment to the drainage channels (to Liffey and Meander Rivers), and disturbance

increased turbidity in the river during the installation of the pipeline outfall.

Mitigation

The pipeline will be installed below ground by open trenching and will be situated at a sufficient

depth to minimise potential impacts on agricultural activities (such as ploughing and mole

drainage). Typically a cover over the pipeline between 0.9 to 1.1 m is normally adopted through

agricultural properties. The proposed pipeline will have cover up to 1.8 mas shown in pipeline

design drawings (Appendix B) and discussed in Section 2.5.1. Subject to the suitability of

existing soils, embedment material around the pipeline will be sourced from the excavated

material. If existing soils are not suitable conforming embedment material will be imported from

a local quarry/supplier. Trench refill material will be sourced from the excavated material and

reinstated to match existing soils layers.


A Construction Environmental Management Plan (CEMP) will be prepared to identify specific

controls associated with construction impacts including possible erosion (refer to Section 4.16.2

for further detail). The construction period is planned to be undertaken during summer months

and will be limited to a three month period (refer to Section 2.6.1).

The outfall in the Meander River will comprise polyethylene pipework (DN225 pipeline size)

anchored on or below the river bed. The bed of the Meander River in the proposed outfall

location has a rocky substrate and therefore risk of erosion during construction will be

minimised.

All outfall construction works will be undertaken in accordance with the DPIWE Manual for

Works in Waterways and Wetlands (2003) and will be included in the CEMP.

Commitment 1 Develop a CEMP to address the potential impacts on surrounding waterways during the construction of the pipeline and outfall. All outfall construction works will be undertaken in accordance with the DPIWE Manual for Works in Waterways and Wetlands (2003).


Potential Impacts

The effluent is proposed to be discharged to the Meander River downstream of the confluence of the Liffey and Meander River. Discharge to the River is expected to be during higher flow months of May through to September (refer to monthly river flow data in Appendix E). The proposed discharge to the Meander River is expected to have a significant improvement on the current receiving waters as the total volume of effluent discharged will be reduced. The Meander River also has increased flows and therefore improved mixing compared to the very low flows and poor mixing currently experienced in the Liffey River.

Although the impact will be reduced compared to the existing conditions, there is potential that the effluent may adversely impact on the river quality and biological health during the times of discharge. As there are downstream properties that may be accessing the river for irrigation, there is also the potential to impact on the quality of water required for irrigation.

Mixing Zone Assessment

A mixing zone modelling assessment was undertaken to determine the mixing zone required to

meet the proposed water quality objectives and is shown in Appendix J. The mixing zone has

been established in accordance with clause 20 of the SPWQM. The assessment includes

consideration of seasonal stream flow characteristics and dilution requirements under different

flow conditions based on data shown in Appendix E. The dilution required to meet the local

Strathbridge 80th percentile WQOs (EPA 2013a) was based upon the concentrations of

toxicants, specifically Ammonia, Nitrate, and recorded metals species.

Under ideal conditions the dilution requirement at the edge of the mixing zone is determined

simply by one toxicant which requires the largest dilution. In the case of Carrick STP effluent,

this is likely to be one of the two key metals analysed, Total Copper or Total Zinc. The dilution

requirements for Total Copper and Total Zinc as calculated were 14 times and 16.5 times for

respectively, however these calculations were based on very small effluent datasets and coarse

assumptions about the receiving water quality. Consequently, these estimates cannot be

considered reliable and a conservative approach to defining the mixing zone has been

advocated by applying an 80 times dilution requirement.

The 80 times dilution, although arbitrary, is in line with the minimum dilution considered

acceptable in the emission limit guidelines for sewage treatment plants that discharge into fresh


waters (EPA 2001), and is about 5 times the dilution requirements based on the (very limited)

data available now.

The mixing zone assessment considered two effluent flow rates:

a. A high flow rate of 10 L/s (864 kL/day) – the proposed standard effluent discharge flow

rate during the non-irrigation season.

b. A low flow rate of 5 L/s (432 kL/day) – a reduced flow that can be manually controlled

during low flow river conditions.

The mixing zone assessment also assessed the impact of two outlet types 1) a single port outlet

and 2) a four port outlet.

A summary of the results of the modelling are shown in Table 15 and Table 16 below and

provided in Appendix J. Key observations from the modelling in relation to the proposed

pipeline and outfall are discussed below.

Table 15 Mixing Zone Extent – Low Discharge Cases

Flow Scenario Length of Mixing ZoneMaximum distance downstream where dilution is less than 80 times.

Width of Mixing Zone Maximum width of the zone with a dilution less than 80 times.

Volumetric (far-field) Dilution

Ratio of river flow rate to discharge flow rate. 1 Port 4 Ports 1 Port 4 Ports

1.0 m3/s (5 L/s discharge) 7Q10

340 m < 1 m 4.5 m < 1 m 200

2.0 m3/s (5 L/s discharge) Intermediate Low Flow

60 m < 1 m 2.5 m < 1 m 400

3.45 m3/s (5L/s discharge) Summer Median Flow

15 m < 1 m 1.5 m < 1 m 690

6.33 m3/s (5 L/s discharge) Autumn Median Flow

3 m < 1 m < 1 m < 1 m 1266

11.08 m3/s (5 L/s discharge) Spring Median Flow

< 1 m < 1 m < 1 m < 1 m 2216

15.22 m3/s (5 L/s discharge) Winter Median Flow

< 1 m < 1 m < 1 m < 1 m 3044

25.0 m3/s (5 L/s discharge) Intermediate High Flow 1

< 1 m < 1 m < 1 m < 1 m 5000


< 1 m < 1 m < 1 m < 1 m 6000


< 1 m < 1 m < 1 m < 1 m 7000


Table 16 Mixing Zone Extent – High Discharge Cases

Flow Scenario Length of Mixing ZoneMaximum distance downstream where dilution is less than 80 times.

Width of Mixing Zone Maximum with of the zone with a dilution less than 80 times.

Volumetric (far-field) Dilution

Ratio of river flow rate to discharge flow rate. 1 Port 4 Ports 1 Port 4 Ports

1.0 m3/s (10 L/s discharge) 7Q10

1400 m 190 m 9.5 m < 1 m 100

2.0 m3/s (10 L/s discharge) Intermediate Low Flow

240 m 14.5 m 4.5 m < 1 m 200

3.45 m3/s (10 L/s discharge) Summer Median Flow

60 m < 1 m 2.5 m < 1 m 345

6.33 m3/s (10 L/s discharge) Autumn Median Flow

13 m < 1 m 1.5 m < 1 m 633

11.08 m3/s (10 L/s discharge) Spring Median Flow

3 m < 1 m < 1 m < 1 m 1108

15.22 m3/s (10 L/s discharge) Winter Median Flow

< 1 m < 1 m < 1 m < 1 m 1522


< 1 m < 1 m < 1 m < 1 m 2500


< 1 m < 1 m < 1 m < 1 m 3000


< 1 m < 1 m < 1 m < 1 m 3500

The modelling shows a significant reduction in the size of the mixing zone with the proposed

four port outlet, compared to a single port outlet.

Mixing zones modelled during median flows of each season with the proposed standard effluent

discharge of 10L/s are all less than 1m in length for a four port outlet. During autumn, winter

and spring, when discharges are expected to occur, river flows are expected to be sufficient to

dilute the effluent flows below levels of toxicity.

During intermediate low river flows (2.0 m3/s), the mixing zones during effluent discharge of

10L/s increases to 14.5 m for a four port outlet. Flows of this rate occur frequently in months

December – March. However as described in Section 2.5.4, no discharge from the STP

storage lagoon is expected in an average rainfall year during these months..

It is possible that effluent may need to be discharged to river on occasions within the October to

April period. This is most likely to be in the months of October and April when the effluent

storage dam may fill prior to effluent irrigation commencing (October) or in April if significant

autumn rains are experienced. As seen in monthly flow data (post 2008) in Appendix E, flow

rates from July through to the end of October are all above 5 m3/s and therefore the mixing zone

during likely discharge will be maintained at less than 1m. Flow rates in April are above 2.0


m3/s and therefore the largest mixing zone is likely to be 14.5 m, if discharge was to be required

in April.

During 7Q10 conditions (the lowest 7-day average flow that occurs once every 10 years), the

mixing zone in high effluent flow conditions is 190 metres in length for a four port outlet. This

mixing zone however can be reduced significantly (<1 m in length) by reducing the effluent flow

to 5 L/s.

Dilution of Non-toxicants

Separate from any potential toxic impacts, discharges will also modify concentrations of

nutrients downstream of the point of discharge. This section investigates this issue.

The impact of effluent discharges on general water quality can be divided into two zones: a

heterogeneous zone immediately downstream of the outlet where plumes of effluent are present

at higher than average concentration, and a homogenous zone downstream where effluent is

evenly mixed across the river and the water quality is effectively even.

The heterogeneous zone / homogenous zone terminology has been adopted to avoid confusion

with the mixing zone, which in this document refers exclusively to meeting the toxicant related

mixing threshold.

The physical location of the boundary between the heterogeneous zone and homogenous zone

has practical application in the selection of monitoring locations and in the discussion of non-

toxicant related water quality. In order for a monitoring location to be representative of the total

flow, it should be located in the homogenous zone.

Table 17 below shows the results of modelling results to determine the distance required to

achieve homogeneity. The four port outlet effectively halves the distance required to achieve

homogeneity.

Table 17 Distance to cross section of relative homogeneity.

Flow Scenario Distance Downstream To Relative Homogeneity

Single Port Four Port

1.0 m3/s (7Q10) > 1500 m 1100 m

2.0 m3/s (Intermediate Low Flow) 1430 m 770 m

3.45 m3/s (Summer Median Flow) 1100 m 580 m

6.33 m3/s (Autumn Median Flow) 800 m 430 m

11.08 m3/s (Spring Median Flow) 600 m 320 m

15.22 m3/s (Winter Median Flow) 500 m 270 m

25.0 m3/s (Intermediate High Flow 1) 390 m 200 m



The potential for sustained changes in water quality in the reach of the Meander River between

the point of discharge and the confluence with the South Esk River were investigated by

comparing the quality of the effluent discharged with the background river water quality. The

effluent water quality assessed was the median effluent quality for the parameters of interest.

The selection of the median quality in this analysis reflects the interest in the potential for

prolonged changes in water quality. The parameters of interest included Total Ammonia,

Nitrogen, Nitrate, Nitrite, Phosphorus, Thermotolerant Coliforms and Enterococci. The

parameter requiring the greatest dilution to achieve 80th percentile background concentrations

was total phosphorus, where a dilution of 900 times was required to achieve background

(Strathbridge) concentrations, followed by total ammonia (746 times). Total Ammonia was


included in both the toxicant and non-toxicant assessments. This is because total ammonia

consists of ammonia (NH3 toxic) and ammonium (NH4 non-toxic). Both fractions are

bioavailable and should be considered with general nutrient impacts i.e. algal growth.

At the proposed standard discharge rate of 10 L/s, the Meander River provides the 900 x

dilution (flow rate of 9 m3/s) to meet background concentrations:

>10% of the time in Summer,

>20% of the time in Autumn,

>75% of the time in Winter, and

>65% of the time in Spring.

The Strathbridge water monitoring site is 10 km from the proposed outfall and therefore the

water quality assumed as background in the assessment can be regarded as conservative. A

comparison of recently analysed water quality at the P1 upstream site (refer to Figure 16) shows

that background phosphorus levels may be slightly higher than the concentrations observed at

Strathbridge (Table 18). However 8 analysis results for the P1 site were not regarded as

sufficient to base the assessment on.

Table 18 Comparison of Strathbridge and P1 monitoring site background water quality

Strathbridge (2003-2009) P1 (Mar 2013- Feb 2014)

Parameter Median 90th # samples Median 90th # samples

Dissolved Oxygen (mg/L) 9.6 11.9 55 9 10.42 7

Field Conductivity (µs/cm) 79.5 137.1 58 66.7 460 6

pH field 7 7.6 55 6.7 7.5 7

Ammonia as N (mg/L) 0.009 0.022 58 0.005 0.011 8

Nitrate as N (mg/L) 0.024 0.338 58 0.091 0.329 8

Nitrite as N (mg/L) 0.001 0.004 58 0.002 0.004 8

Total Nitrogen as N (mg/L) 0.285 0.619 58 0.28 0.659 8

Dissolved Reactive Phosphorus as P (mg/L)

0.003 0.005 58 0.005 0.012 8

Total Phosphorus as P (mg/L) 0.015 0.025 58 0.0195 0.0296 8

Enterococci (cfu/100mL) n/a n/a n/a 50 154 8

Thermotolerant coliforms (cfu/100mL)

n/a n/a n/a 225 392 8

As discussed above, the effluent discharged to the river will generally commence in late autumn

(April or more likely May) at the end of the irrigation season when the storage dam has filled and

will continue throughout May, June, July, August and September. Discharge is expected to

cease in September but may continue into October. Based on post 2008 flow data in Appendix

E, the months when insufficient river flow may be experienced to achieve a 900 dilution, are

mostly likely to be April, May and June. The mixing assessment suggests that the

heterogeneous zone for phosphorus during these months may extend 770 m downstream. This

may result in slight changes to algal growth and biological indicators within this region. Given

the downstream offtake for stock watering and irrigation is 740m downstream and

concentrations would be close to background levels, the impact on use for stock watering and

irrigation is likely to be low. A summary of the expected mixing zone (toxicants) and

heterogeneous zone (non-toxicants) under the different proposed discharge arrangements are

shown in Table 19.


The overall mixing of toxicants and nutrients will be significantly improved compared to the

existing outfall in the Liffey River.

Table 19 Summary of Proposed Discharge Impacts on Receiving Waters

Month

(Discharge Plan)

River Flow

(m3/s)

Effluent

Flow (L/s)

Mixing Zone

(toxicants)

Approximate

Heterogeneous Zone

(non-toxicants)

April (possible

discharge to river)

2.25 (min) 10 14.5 m (max) 770 m (max)

6.5 (median) 10 <1m (median) 430 (median)

May (regular

discharge to river)

2.9 (min) 10 14.5 (max) 770 m (max)

8.1 (median) 10 <1m (median) 375 m (median)

June, July,

August,

September

(regular discharge

to river)

3.5 (min) 10 <1 m 580 m (max

15.6 (median 10 <1 m 270 m (median)

October (possible

discharge to river)

5.72 (min) 10 <1 m 540 m (max)

9.52 (median) 10 <1 m 375 m (median)

November –

March (no

planned discharge

to river

emergency only)

1.0 (7Q10) 5 (manual) <1 m 770 m (max)

2.85 (median) 10 14.5 (max) 770 m (max)

Mitigation

The pipeline outfall is planned to be anchored in the centre of the river 1 m below the surface

with a four port outlet to maximise dispersion and mixing. The proposed four port outlet and will

minimise the size of the effluent mixing zone.

Commitment 2 Construct the effluent outfall pipeline to the middle of the Meander River using a four port outlet at a depth 1m below the surface to maximise mixing and dispersion and verify the mixing zone.

The discharge controls and telemetry described in Section 2.5.5 will permit discharge to the

Meander River at 10L/s when the effluent treatment storage dam is full (135.7 m). Discharge is

expected to occur regularly during months of May (autumn) through to September (spring). The

flow rate of 10L/s is sufficient to maintain some self-cleansing in the pipeline, therefore

minimising the risk of sediment fallout and maintenance issues. The bed of the river in the

outfall zone is of a rocky substrate and the proposed effluent flow rates are unlikely to result

scouring and erosion.

Under planned discharge management of discharging to the river between May and September

(& possibly extending to April and October in some years), the mixing zone to achieve the local

WQOs will be restricted to 14.5 metre in length and width and will most often be <1 m. The

heterogeneous zone where non-toxicant parameters such as nutrients will be elevated during

these times is expected to extend 270 m – 770 m.


With the proposed outfall and discharge management, the quality of water at the known

downstream offtake (740 metres) is unlikely to be significantly impacted for the use for stock

watering and irrigation. This is because for the majority of discharge periods the heterogeneous

zone will be limited to 580 m in length and will only occasionally extend to 770m. The risk of

sustained negative impact from elevated nutrients in the areas downstream of the outfall will

however be monitored via an ambient monitoring program (refer to Section 5.2).

Monitoring will be undertaken as described in Section 5.2 to verify the mixing zone and the impacts on ambient water quality. The downstream monitoring site is proposed to be located at Westwood Road bridge approximately 1 km downstream from the outfall (refer to Section 5.2). The location of this monitoring point based on the assessment undertaken should be sufficiently far downstream to be outside the mixing zone and outside the heterogenous non-toxicant zone and therefore is suitable to monitor any potential changes to receiving water quality.

Biological monitoring will be undertaken in autumn and spring to assess the impact on aquatic ecology from the proposed new effluent outfall.

The extent of the impact of the discharge will also be verified by undertaking plume dispersion

monitoring. The current Moat property garden pump will be relocated either upstream from the

discharge or further downstream outside of the mixing zone and heterogeneous zones.

Commitment 3 Undertake routine effluent monitoring, ambient monitoring and a plume verification monitoring event in the Meander River in accordance with an EPA approved ambient monitoring plan.

In both an average and wet year the 25 ML storage dam will be more than sufficient to maintain

buffer storage such that discharge to the Meander River is not required during low flow summer

and autumn months. Therefore effluent discharge is not planned to occur in 7Q10 (1.0 m3/s)

flow conditions or low flow periods (<2.0 m3/s) and would be managed as an abnormal

discharge only. This would require manually adjusting the outlet valve to slow the effluent

discharge rate from 10 L/s to 5 L/s or as low as feasible whilst not allowing the effluent to

overflow from the storage lagoon. The reduced effluent flow in lower river flow conditions would

also minimise the area in which elevated nutrients would occur.

There is no general public access to the Meander River in the vicinity of the Moat Property. Given the restricted public access, timing of discharge is planned to occur during cooler months and the limited size of the mixing zone the health risks from swimming or fishing within the outfall area is extremely low. As a precaution “no swimming” signage is proposed to be erected in the immediate vicinity of the effluent discharge. Further controls in relation to public health and safety are discussed in Section 4.12.

Given the existing 25 ML storage dam can store 39 days’ worth of effluent and periods of low river flow will coincide with peak demands for effluent irrigation, there is a very low likelihood that discharge during 7Q10 low flows will be required. Regardless, if some circumstances required discharge during the irrigation season in the peak of summer the reduced effluent flow of 5 L/s could be manually applied to minimise the mixing zone area.

In the case of the storage dam being at the high level limit (135.7 m AHD), there remains 0.3 metres freeboard in the storage dam that would be capable of holding a further 3 days effluent volume. This would require manual control to override the effluent discharge but does provide some additional contingency should both irrigation and river discharge be unavailable.

The pipeline, valves and telemetry will be routinely checked and preventatively maintained by TasWater to ensure it is operational at all times. Remote alarms will be in place to alert TasWater of any malfunctioning control valves as described in Section 2.5.5.


Commitment 4 Maintain a system of operating controls to maximise discharge, while maintaining mixing zone, during high flow conditions, and avoiding discharge during flow conditions including the provision of remote alarms to detect control valve failures

Commitment 5 Maintain preventative pipeline and telemetry system maintenance via routine inspection.

In the event of an unforseen pipeline outage when the dam is full the effluent lagoons as identified above will able to hold an additional 3 days storage to ensure that there is no uncontrolled discharge. This is regarded as sufficient time to undertake an urgent repair.

The above described operating controls will be incorporated into the updated Carrick Operations Manual described in Section 4.16.3 and the future Carrick Discharge Management Plan (a requirement of the existing EPN 8121/2).

Effluent will continue to be routinely monitored in accordance with the discharge limits specified in EPN 8121/2(r1) including blue green algae monitoring on a monthly basis. The existing control measures described in Section 2.4.3 to prevent the outbreak of BGA will be maintained. Ambient water will be monitored for an extended period from October through to April. During the months when blue green algae (BGA) are most likely, there is no planned discharge to the Meander River. However If blue green algae is detected in effluent, there will be a commitment not to discharge to receiving waters in accordance with TasWater’s Blue Green Algae Prevention Control and Management Plan, Dec 2011(Appendix K).

Commitment 6 Management of effluent containing BGA in accordance with TasWater’s Blue Green Algae Prevention Control and Management Plan Dec 2011, including monitoring of BGA in accordance with Section 5.2

The Liffey River is expected to experience significant improvement in water quality when the new pipeline and discharge location is established. The total loading of pollutants entering the combined Liffey and Meander receiving waters due to the ability to irrigate, are expected to be reduced by approximately 40% and the impact area (mixing zone) of the effluent discharge will also be reduced.

Therefore with the above described operational practices including controlled discharge and extended four port outfall to the middle of the river, the risk of adverse impacts on ambient water quality outside the small mixing zone will be low. The impact to ambient water quality from the occurrence of discharges during lower flows in autumn and summer are unlikely, due to the ability to mitigate via operational and contingency controls, the ability to moderate effluent flows and withhold effluent for extended periods.

The medium term plan for the Carrick STP is to undergo a process upgrade to improve the current effluent quality. Further to this, the volume of effluent from Carrick STP is likely to reduce significantly if Hadspen region is treated via a new STP. The combined effluent quality improvement and reduced volume would further reduce the impact on the receiving waters and may eliminate the mixing zone altogether. If a full reuse scheme is able to be implemented in future, then the proposed discharge to the Meander River would be rarely required.

Commitment 7 Undertake improvements to the Carrick STP to ensure that future effluent complies with EPN limits.

4.3 Groundwater


The key legislation, policy and guidelines of relevance to groundwater in Tasmania are:


State Policy on Water Quality Management 1997 (SPWQM)

Water Management Act 1999


For a description of the existing groundwater conditions, refer to Section 3.6. The existing clay

lined storage dam is regularly inspected to ensure that the condition of the lagoon clay liner is

not drying or cracking. There has been no previous evidence of issues associated with

compromised lagoon clay liner integrity.


The proposed construction involves only shallow earthworks (0.9 to 1.8 m) above the

groundwater level (3.0-3.5 m) and therefore there are no identified impacts on groundwater

during this stage of the project.


Potential impacts to groundwater could occur under if there was a leak from the pipeline. The

result may be increased lateral flows of shallow groundwater ending up in surface waters of the

Liffey and Meander River.

Regular inspections of the property and very low infiltration rates of clayey alluvial terrace soils

will ensure that any leaks will be promptly detected.

The existing effluent storage dam will continue to be regularly inspected. The time when the

clay lining of the storage dam will be exposed is limited (1-3 months) and will not be dissimilar to

current conditions. Drying and cracking of the lagoon liner therefore is not regarded as a

significant risk.

4.4 Noise Emissions


The key legislation, policy and guidelines of relevance to noise management in Tasmania are:

EMPCA 1994, particularly Section 53 (environmental nuisance)

Environmental Management and Pollution Control (Miscellaneous Noise) Regulations

2014.

Environment Protection Policy (Noise) 2009

Noise Measurement Procedures Manual (NMPM), July 2004

Noise impacts to people working on the construction or operation of the STP upgrades must be

managed in accordance with the Workplace Health and Safety Act 2012 and associated

regulations.

In addition to these general requirements, the current Carrick STP EPN 8121/2 (r1) sets quality

limits for noise emissions as follows.

Noise emissions from the activity when measured at any noise sensitive premises in other

ownership and expressed as the equivalent continuous A-weighted sound pressure level must

not exceed:

50 dB(A) between the hours of 0800 and 1800 (day time)

45 dB(A) between the hours of 1800 and 2200 (evening time)

40 dB(A) between the hours of 2200 and 0800 (night time)


All methods of measurement must be in accordance with the Tasmanian Noise Measurement

Procedures Manual issued by the Director.


The current sites activities do not generate noise at detectable levels to the general public of

nearby residences.


There is likely to be noise generated during construction from vehicles and machinery, which

will occur during daylight hours only throughout the proposed three month construction period.

The residents nearest the construction area are located approximately 320 metres away (the

Moat property owner) and approximately 400 metres in a northerly direction across the Meander

River. Construction activities will typically be undertaken five days per week between the hours

of 7.00 am and 6.00 pm. Construction activities will not be undertaken on Sundays or public

holidays and in such a manner as not to disturb the property owner or neighbours with noise. All

vehicles and machinery will be maintained to minimise noise impacts on site workers and

hearing protection will be worn in accordance with workplace standards.

Given the distance to the nearest residents and the proposed construction hours, the noise

impact to residents during construction is considered to be minimal.


During the operational phase of the project, noise impacts will not be of concern as the effluent

it discharged via gravity.

Accordingly the operational noise impacts associated with the Carrick STP new pipeline and

outfall are considered to be negligible.

4.5 Solid and Controlled Waste Management


The key legislation, policy and guidelines of relevance to the management of solid and

controlled wastes in Tasmania are:

Environmental Management and Pollution Control Act 1994

Environmental Management and Pollution Control (Waste Management) Regulations

2010

Environmental Management and Pollution Control (Controlled Waste Tracking)

Regulations 2010

National Waste Policy 2009 (NWP)

Movement of Controlled Waste Between States and Territories National Environment

Protection Measure (NEPM)

Used Packaging Materials NEPM

The key performance requirements, as related to the legislation outlined above are:

Approval must be sought prior to controlled wastes being transported from the site.

Controlled wastes must be removed from the site by an approved controlled waste

transporter.

Controlled wastes must be disposed of at an approved disposal facility.



The existing effluent drainage channel to the Liffey River requires periodic clean out of

vegetation to allow free drainage. Plants are removed, but left on the Moat property for natural

biodegrading.

The current STP lagoons and storage dam are periodically removed of sludge build up.

Biosolids from the lagoon and dam are a controlled waste and are managed according to

TasWater biosolids management plan and are transported and disposed of via licensed

transporter and to an approved biosolids treatment facility.


During construction, potential solid waste generation is restricted to construction materials and

packaging. Any construction materials, packaging waste or waste generated by the contractors

will be stored in designated laydown areas or sealed bins. These materials will then be disposed

of regularly through the existing solid waste and recycling facilities. Waste management during

construction will be undertaken in accordance with the CEMP. This plan will identify

opportunities for waste reduction and recycling.

The CEMP will set a performance standard of requirements for construction waste.

Decommissioning of the existing discharge channel will involve clean out of vegetation in

accordance with current TasWater maintenance practices. Following construction of the new

pipeline, TasWater will no longer undertake vegetation clearance of this channel.

Decommissioning of the drainage channel is described in Section 6.

Sludge removal of the STP lagoons and storage dam will continue as per the existing

operations.


The pipeline and outfall will not generate solid waste during operation.

4.6 Dangerous Goods


The construction and operation of the proposed new pipeline and reuse scheme must fulfil the

requirements of the following legislation and policy in relation to dangerous goods:

Australian Code for the Transport of Dangerous Goods by Road and Rail

Dangerous Substances (Safe Handling) Act 2005 and associated regulations

Australian Dangerous Goods Code (7th edition)

Relevant Australian Standards (e.g. AS 1940 and AS 3780)

In addition to these requirements, the current Carrick STP EPN 8121/2(r1) Schedule 3 sets

states the storage and handling of dangerous goods must comply, as a minimum standard, with

the requirements contained in the relevant State Acts and Regulations, and any subsequent

amendments including:

Dangerous Goods (Safe Transport) Act 1998

Dangerous Goods (Road and Rail Transport) Regulations 1998

Workplace Health and Safety Act 2012

Workplace Health and Safety Regulations 2012



Minor quantities of dangerous goods are stored at the Carrick STP in compliance with the EPN

8121.


Small quantities of fuel, lubricants and other chemicals may be stored on-site during the

construction phase of the project. The transport and storage of these dangerous goods will be in

accordance with relevant standards and legislative requirements.

The CEMP, to be developed prior to construction, will detail the dangerous goods to be

transported, stored and used during construction and the appropriate storage and handling

procedures. The CEMP will also dictate procedures in the event of a leak or spill at the site to

prevent impacts to the environment and to human health (refer to 4.12).


There is no proposed additional storage of dangerous goods associated with the proposed

development operation. All storage and handling will be undertaken in accordance with the

existing EPN 8121(r1) and the operations manual for the Carrick STP.

4.7 Biodiversity and Natural Values


Biodiversity and nature conservation values in Tasmania are protected by a range of legislation

and policy. The key documents relevant to this project include:

Commonwealth Environment & Biodiversity Conservation Act 1999 (EPBC Act)

Tasmanian Threatened Species Protection Act 1995 (TSP Act)

Regional Forestry Agreement

Forest Practices Act 1985 and associated regulations

Weed Management Act 1999

Nature Conservation Act 2002

The project is not likely to require approval under the Environment Protection and Biodiversity

Conservation Act 1999 as there have been no matters of national environmental significance or

Commonwealth land identified within the development footprint.

Biodiversity and nature conservation performance requirements are broad-ranging and relate to

management of the project in accordance with the above-mentioned legislation.

Key performance requirements include:

Avoid and/or mitigate against potential impacts to native flora and fauna.

Avoid impacts to listed flora, fauna and vegetation communities. Where avoidance is not

possible minimise impacts as far as practicable.

Minimise the potential for weed incursions and control/eradicate any declared weeds

arising as a result of the development.

Any flora and fauna surveys must, as a minimum, comply with the requirements of the

document Guidelines for Natural Values Assessments published by the Department of Primary

Industries, Parks, Water and Environment (DPIPWE). The methodology for surveys should be

developed in consultation with the Department.



The proposed new discharge site are dominated by introduced species. The land has been

agricultural for a considerable period and the species and assemblages found are of very low

biological conservation significance. A detailed description of the existing conditions are

provided in Sections 3.3.5 (aquatic ecology) 3.3.6 (flora), 3.3.7 (terrestrial fauna) and 3.3.8

(pests and diseases).


Impacts to native terrestrial flora and fauna during construction are anticipated to be minimal.

This is due to the highly disturbed nature of the site and the fact that threatened species or

vegetation communities are not known to be present. There will be some disturbance to the

physical integrity of the Meander River through the establishment of the outfall pipeline. All

works will be undertaken in accordance with the DPIWE Manual for Works and Waterways and

Wetlands in order to mitigate and minimise impacts.

There is potential to introduce weeds into the site, or spread weeds from the site to other areas

during construction. To manage potential weed introduction and spread control measures will

be established and documented in the CEMP, including:

Vehicle and machinery washdown in accordance with the Washdown Guidelines for

Weed and Disease Control Edition 1 (DPIWE).

Pre-construction weed control for any declared weeds in the immediate vicinity of works

in order to minimise the potential for disturbance and spread.

Post construction visual inspection of weed occurrence and follow up control if required.

Any material brought onto the site will be clean fill.


Placement of the outfall in the centre of the river will avoid a source of bank erosion. Once the

outfall is constructed there are no anticipated impacts to terrestrial flora and fauna. Rocky

substrate in the river suggests that scouring will not be an issue. Potential impacts to aquatic

species are addressed under Section 4.2.4.

4.8 Greenhouse Gases and Ozone Depleting Substances


Greenhouse gas emissions are controlled and reported through a number of legislative tools. At

a National level Australia introduced a price on carbon on 1 July 2012, as set out in the Clean

Energy Legislation Amendment Act 2012. This is aimed at reducing carbon emissions by

reducing energy consumption, promoting energy efficiencies and the use of renewable energy

options.

The introduction of a carbon pricing scheme generally does not alter existing reporting

requirements for GHG under the National Greenhouse and Energy Report (NGER) scheme

generally still apply.

At a State level, Climate Change (State Action) Act 2008 and Climate Smart Tasmania: A 2020

Climate Change Strategy (2013) set outs the priority action areas for Tasmania's response to

climate change from 2011 going forward.


TasWater currently report on greenhouse gas (GHG) emissions from its STPs and will continue

to do so once the proposed works are undertaken.



GHG impacts associated with the construction phase include minor machinery and vehicle

emissions and energy use.

The construction phase for the Carrick STP new pipeline and outfall is anticipated to last

approximately three months, during which time GHG emission from these sources is

unavoidable. To minimise GHG emissions, all machinery and vehicles will be well maintained

and energy use will be minimised.


The effluent will be discharged via gravity feed and as such the operational phase of the project

is not anticipated to result in a significant change in GHG emissions with reference to existing

conditions.

Additional energy use by telemetry and valves proposed will be negligible.

TasWater reports annually on its greenhouse emissions and will continue to do so, allowing a

comparison between existing GHG emissions and future emissions resulting from the proposed

development to be made.

4.9 Heritage


Aboriginal and European Heritage values in Tasmania are protected by a range of legislation

and policy. The key documents relevant to this project include the Aboriginal Relics Act 1975

and the Historic Cultural Heritage Act 1995.

The Aboriginal Relics Act 1975 governs the treatment of Aboriginal relics and protected sites in

Tasmania. It is an offence to destroy, damage, deface, conceal or otherwise interfere with a

relic. Aboriginal cultural heritage is defined as “any place, site or object made or created by, or

bearing the signs of the activities of, the original inhabitants of Australia or descendants of such

inhabitants in or before 1876 in Tasmania”.

The advice of the Tasmanian Heritage Office should be sought with regard to effects on places

listed on the Tasmanian Heritage Register and to establish regulatory requirements for heritage

values, places and landscapes.


An Aboriginal Cultural Heritage Survey was undertaken by Rocky Sainty in May 2001 and a

European heritage survey was undertaken by CEE Consulting in 2002. No Aboriginal sites or

historic sites of significances were identified the within the study area.


The Aboriginal Cultural and European Heritage surveys undertaken did not identify any heritage

sites within the study area and therefore there are no anticipated impacts resulting from

construction of the proposed outfall pipeline.

However if any Aboriginal relics are identified during construction, the provisions of the

Aboriginal Relics Act 1975 will apply and a permit to damage or destroy Aboriginal heritage will

be required.


There are no expected impacts on Aboriginal or European heritage as a result of operation of

the proposed new pipeline and outfall.


4.10 Visual Effects

4.10.1 Legislative and Policy Requirements

Tasmania’s landscape is an important consideration in any land use planning exercise because

of its cultural, ecological and/or scenic qualities. The proposed new pipeline and outfall for the

Carrick STP will be sited on the TasWater STP and adjacent Moat property.

The key legislative document addressing visual impacts in the area are the:

Meander Valley Interim Planning Scheme 2013 (the Planning Scheme)

The objectives of the Resource Management and Planning System (RMPS) as set out in

Schedule 1 of LUPAA 1993

These two documents deal with the broader issues of maintaining the environmental and social

values of the area of which the visual landscape is a relevant factor.


The proposed site for the establishment of the new discharge pipeline and outfall is not visible

by the general public. Therefore visual impact during construction will be negligible.


The pipeline will be buried and the effluent outfall will be anchored to the bottom of the Meander

River. Therefore the project will not be visible, once constructed.

Accordingly, it is not anticipated that the proposed development will have an impact upon the

visual amenity of the surrounding areas.

4.11 Socio-economic Issues including Land Use and Development

The Tasmania Planning Commission (TPC), in their State of Environment Reports and in the

preparation of other studies and documents, has recognised the importance of maintaining

landscape values within Tasmania, in particular for the following reasons:

Protecting landscape values can sometimes help to protect a range of other

environmental services. Landscape values often have an association with environmental

and natural resource quality; the values that people appreciate in a landscape are often

also important ecologically.

The landscape values of the State remain a major draw card for the tourism industry and

these landscapes should be managed as a key component of tourism infrastructure.

The objectives of the Resource Management and Planning System (RMPS) as set out in

Schedule 1 of LUPAA 1993 also deal with the broader issues of maintaining the environmental

and social values of the area.

4.11.1 Impacts on Land Use and Development

The Moat property is zoned Rural Resource (refer to Figure 4). The underground pipeline is

exempt from the provisions of the Land Use Planning and Approvals Act 1993 (LUPAA) in

accordance with Section 11(d) of the Water and Sewerage Industry (General) Regulations

2009. The outfall is not exempt under the Regulations. It is classified according to the Utilities

use class which applies to the STP, which is discretionary in the Rural Resource Zone.

The outfall also requires a discretionary permit in accordance with Clause 25(1) of the

Environmental Management and Pollution Control Act 1994.


The proposed pipeline and outfall construction not expected to limit further land use or

development in the area.

4.11.2 Impacts on Land Values

The new discharge and reduced discharge to ambient waters will contribute significantly to

improving the water quality in the Liffey and Meander River by significantly reducing the total

nitrogen and phosphorus loads discharged from the STP to the receiving environment. This

may have an indirect positive impact on downstream properties accessing the water.

There are no proposed changes to the existing Carrick STP and existing buffer distances

maintained will not impact land values as this is an existing operation.

4.11.3 Impacts on Other Industries

The construction of the new pipeline and discharge will provide an increased employment

potential during the construction period within the Carrick and municipality.

4.11.4 Impacts on Local and State Labour Markets

The construction phase of the project will involve the engagement of a construction contractor.

Any such contract company is likely to be based in or around Carrick and would require in the

order of 10 people for a construction period of approximately 2-3 months, as per the current

construction schedule.

4.11.5 Local Raw Materials

Materials, such as pipework and pumps will be sourced from off-site however the suppliers are

not yet known.

4.11.6 Total Capital Investment

The total capital funding allocated towards the Carrick STP new pipeline and discharge outfall is

$360,000.

4.11.7 Community Impacts

TasWater employs a small number of operational staff to routinely undertake maintenance

operations at the Carrick STP and across other STPs and these jobs will remain following the

upgrade of the STP. The proposal will significantly benefit the community by providing the

infrastructure necessary for the growth and expansion of the townships of Carrick and Hadspen

and the local agricultural industry.

4.12 Health and Safety Issues


The Carrick STP new discharge pipeline and outfall must comply with all relevant State and

Commonwealth legislation and TasWater’s Occupational Health and Safety Policy (Oct 2011)

with respect to the health and safety of staff, contractors, and the community. In particular, the

construction and operation of the plant must comply with the Tasmanian Work Health and

Safety Act 2012 and, Work Health and Safety Regulations 2012 and AS 4804 Occupational

Health and Safety Management Systems.

The regulations require notification of prescribed incidents/accidents or dangerous occurrences

are to be made to Work Cover Tasmania.

The Environmental Management and Pollution Control Act 1994 (Section 5) and the Public

Health Act 1997 also have outline responsibilities on preventing human health impacts.



Construction contractors will be required to provide documentation outlining their systems for

managing health and safety during construction. All contractors will be required to undertake all

works in accordance with TasWater’s Occupational Health and Safety Policy (Oct 2011)


Once completed, the operation of the new pipeline and outfall will be undertaken in accordance with the requirements of the Tasmanian Workplace Health and Safety Act 2012 and Workplace

Health and Safety Regulations 2012.

The Carrick STP Operating Manual will address Health and Safety issues such as:

Identification of safety hazards and controls.

Procedures for operational control of potentially hazardous equipment.

Roles and responsibilities for specific management representatives who have a defined

role for occupational health and safety management of the facility.

Development of a competency, training and awareness program for employees

associated with the facility.

Development of an Emergency Response Plan.

Development of an incident management system.

4.13 Hazard Analysis and Risk Assessment

4.13.1 Risk Assessment Summary

The analysis of hazards is central to the effective management of health, safety and environ-

mental risks for the project. This section provides the hazard analysis and risk assessment that

was conducted to identify and manage hazards during the concept development phase, while

considering the construction and operational phases.

A risk assessment was conducted to assess the potential risks associated with the Carrick New

Pipeline and Outfall Proposal. The Risk Assessment considered hazards leading to potential

risks, with evaluation of the likelihood and consequence of events being risk ranked according

to a Sustainability Risk Assessment Tool (Appendix L) Risks were firstly evaluated without

considering mitigation strategies and secondly including the strategies. In most cases there was

a decrease in risk due to the mitigation. Summary results from the risk assessment are shown in

Table 20. There were no identified residual extreme, high or medium risks.

Table 20 Sustainability Risk Assessment Summary After Mitigation

Ranking No. Risk Summary Effects and Mitigation

Extreme 0 Not applicable N/A

High 0 No high level risks were identified during construction or operation.

N/A

Medium 0 No residual Medium risks were identified N/A

Low 13 Refer to Appendix O Section 4.1 to 4.14

Total 13


4.13.2 Contingency Planning

The following contingency plan framework provides a guide for TasWater to develop a

Contingency Management Plan for the proposed pipeline and outfall.

This process is proposed for initiating and implementing contingency plans and is detailed

below in Figure 15.

Identify and Assess Potential Risks from

Available Information and

Knowledge

Rev

iew

an

d Im

pro

vem

ent

Develop Actions for Risk Treatment

Develop Contingency Plan

Management Endorsement

Training and Implementation

Figure 15 Staged Approach for Implementing Contingency Plans

4.13.3 Review and Continual Improvement

The contingency plan will incorporate a process to regularly review the plan and implement

improvements to the system wherever applicable.

4.13.4 Incident Notification and Emergency Communication

Incident notification and emergency communication will include the following:

An internal protocol for reporting an incident to responsible officers (including main and

back-up staff names, titles and phone numbers).

Reporting aspects and impacts to relevant emergency authorities.

Incidents will be reported in accordance with Section 32 of EMPCA and condition G2 of EPN

8121/2.


Table 21 below provides contact details for relevant emergency authorities. Relevant contact

details of downstream water users will also be incorporated into the Contingency Management

Plan.

Table 21 Contact Details of Relevant Emergency Authorities

Emergency Authority Contact Details

TasWater 13 6992

Meander Valley Council 03 6393 5300

Police, Fire, Ambulance 000. Mobiles can also use 112.

State Emergency Service (Storm and Flood

Response)

132 500

Aurora (electricity) 13 2004

Powerco (gas) 180 2111

DIER (State roads and bridges) 1800 005 282

Environmental emergency 1800 005 171

Poisons Information Centre 131 126

4.13.5 Training and Implementation

It is important that the roles and responsibilities within the contingency plan are formally

documented and communicated to relevant staff. Any training requirements related to the

contingency plan will be provided. Control/risk treatment activities identified for high risk aspects

will be implemented as soon as practicable.

Commitment 8 A Contingency Management Plan for the Carrick New Pipeline and Outfall will be developed prior to the scheme commencing.

4.14 Fire Risk


The construction and operation of the proposal must fulfil the requirements of the following

legislative and policy requirements in relation to fire risk:

Fire Services Act 1979

Workplace Health and Safety Act 2012

Buildings and associated fire controls must be designed in accordance with the Building Code

of Australia.


A summary of the existing environment and fire risk is provided in Section 3.11.


Ignition sources associated with the construction phase are limited to use of machinery, vehicles

and fuels. All vehicles and machinery will be kept in good working order to minimise the


potential for fires on site. Any fuels required during the construction phase will be limited in

quantity and will be stored in appropriately bunded facilities.

Appropriate firefighting equipment will be kept on site during the construction phase and site

staff trained in emergency procedures and use of firefighting equipment.


The two key aspects relating to fire prevention and control at the site are:

Fires generated on the site, or migrating off the site into surrounding areas.

The potential for wildfires to enter the site from surrounding areas.

The operation of the new discharge location poses negligible fire risk as there are no ignition

sources or significant fuel sources associated with the pipeline.

Potential fire sources include lightning strikes as well as spot fires from fires further afield.

However external fire is considered to pose a very low risk to the operation of the proposed new

discharge location is surrounded by irrigated agricultural land and the Liffey and Meander

confluence.

TasWater maintains fire management plans for their STP facilities. The fire

management/emergency management plan for Carrick will be updated to incorporate the

proposed operational features. This plan relies on support from local fire authorities and State

Emergency Services and is regularly reviewed and updated.

4.15 Infrastructure and Off-site Ancillary Facilities


All accesses, works and activities affecting the surrounding road ways are required to comply

with the relevant Austroad Guidelines, Council development application requirements and

relevant Australian Standards including AS 1742.3.


Construction based infrastructure impacts relate to road use for movement of machinery or

materials to and from the site. Access for construction of the proposed pipeline and pump will be

via the existing roadway system, along Meander Valley Highway and via roads accessing the

Carrick STP and the Moat property. It is not expected the upgrading works will impact any other

road users in the area, given the relatively short construction timeframe of 2-3 months.

There will be a negligible increase to road traffic associated with the Carrick STP upgrade as all

heavy machinery will be stored onsite for the duration of construction.

The proposed new discharge pipeline requires construction within an easement area for the

Tasmanian Gas Pipeline as shown in Drawing 32-172221-C002, Appendix B. Tasmanian Gas

Pipeline (TGP) has been consulted during the design of the effluent pipeline. Further

consultation will be undertaken with TGP and mandatory work requirements and work

procedures required by TGP will be addressed in TasWater’s CEMP.


Once the construction of the proposed pipeline is complete, energy and water utilisation from

existing site sources will remain similar to the existing and the upgrades are not anticipated to

impact upon associated infrastructure.

There are no significant impacts to off-site infrastructure facilities anticipated as a result of the

proposed activities.


As is currently the case, traffic operational movements from the site will continue, which will be

via Meander Valley Highway.

Impacts on Power Supply

The existing power supply to Carrick STP is sufficient for running additional controls at the STP

site. Controlled valves located at the pivot pump station will require power supply from the Moat

property power pole. This power usage will be small and will be managed according to the

Agreement for the use of Recycled Water between TasWater and the Moat owner.

4.16 Environmental Management Systems

4.16.1 Management System Description

The following management systems and operational plans will be applied to this proposed

activity.

4.16.2 Construction Environmental Management Plan (CEMP)

A CEMP will be prepared prior to construction and will include as a minimum, the following:

Identification of environmental risk and controls.

Development and implementation of documented procedures for operational control.

Appointment of a specific management representative who has a defined role for

environmental management of the site.

Clear outline of competency and training (if required) for employees associated with the

environmental performance of the site.

Development and implementation of an environmental monitoring program with

documented procedures (if required).

Development and implementation of an incident management system.

Development and implementation of an auditing program for both during and at the

completion of the construction phase.

The relevant sections of International Standard Organisation (ISO) 14001 EMS will be used for

guidance when these minimum requirements are addressed.

It will be TasWater’s responsibility to prepare and implement a CEMP prior to the construction

phase of the project. The Contractor will be required to nominate an Environmental

Representative, with responsibility for ensuring that the needs of the CEMP are met. It is

expected that the CEMP will encompass the relevant issues identified in Section 4 and include,

but not be limited to the following key elements:

Site Management – A system will be developed to manage entry and exit from the site

and to ensure that impacts from works do not occur outside the contract site.

Erosion Control – The CEMP will include an erosion management system, which outlines

procedures to ensure no significant erosion or runoff as a result of construction works.

Dangerous Goods – A system will be established for managing the delivery, storage use

and disposal of all dangerous goods required for construction.

Air Quality – A visual monitoring program to identify unacceptable levels of dust during

construction will be implemented. The CEMP will also outline mitigation measures to be

employed in the instance that dust levels are elevated. Such measures may include the

use of water carts, or ceasing work in certain weather conditions.


Noise Management – The CEMP will outline measures for notifying the closest local

residents of noise generating activities, as well as stipulating clear hours of operation.

The CEMP will also outline any necessary controls to ensure noise levels at the

construction site are in accordance with workplace standards, including measures such

as the use of hearing protection if required.

Traffic Management – The CEMP will outline clear procedures for traffic management,

including signage, timing, safety and notification of local area users.

Health and Safety – A system will be developed to manage health and safety on site

during the works.

Waste Management – Procedures for waste management during construction, including

designated lay-down areas, and transport and disposal procedures will be developed.

Weed and Disease Control – The CEMP will develop and implement procedures for

wash-down of equipment before entering the site in order to avoid the introduction of

weeds, pest and diseases. This section will also outline weed control measures to be

implemented before and after construction to ensure the works do not increase the

infestation of weeds presently located at the site.

Incident Management – An incident reporting and follow up system will be established in

order to respond effectively and efficiently in the unlikely event of an environmental

incident.

4.16.3 TasWater Carrick STP Operational Manual

TasWater will update is Carrick STP Operational Manual to include all key aspects of the new

discharge management outlined in this DPEMP. This may be incorporated in the form of an

appendix to the existing operational manual. The Operations Manual will be updated within 4-6

months following the commissioning period.

Commitment 9 The Carrick STP Operations Manual will be updated (where required) within 4-6 months following the commissioning period.

4.17 Cumulative and Interactive effects

There are no cumulative impacts expected as a result of the proposed new discharge pipeline

and outfall. The volume of effluent discharged to ambient water is expected to reduce as a

result of this development as it allows the effluent to be used for an effluent irrigation (reuse)

scheme. Therefore there is expected to be an overall decrease in the mass nutrient loads to the

Meander River from the Carrick STP.


5. Monitoring and Review5.1 Monitoring Aim and Objectives

The monitoring program is designed to meet the following objectives:

Monitoring of compliance with emission standards and other performance requirements

identified in the DPEMP.

Assessing the effectiveness of the performance requirements and environmental

safeguards in achieving environmental quality objectives.

Assessing the extent to which the predictions of environmental effects in the DPEMP

have eventuated.

Assessing compliance with commitments made in the DPEMP.

Monitoring compliance with the requirements of the EPN for the activity.

In the event that a permit is issued by the Council under the Land Use Planning and Approvals

Act 1993, monitoring for compliance with conditions of that permit will also be required.

5.2 Monitoring Program

The proposed monitoring program includes:

Effluent Monitoring

Ambient Monitoring (Discharge to Meander River)

5.2.1 Effluent Monitoring

Effluent monitoring during discharge to the Meander River will be maintained according to the

current Carrick STP EPN No. 8121/2 monitoring requirements (Condition M1 and Attachment

2). However it is proposed that the location for monitoring compliance will be from the point of

discharge. With the proposed setup the point of discharge will be the storage dam, rather than

the treatment plant lagoon. Parameters proposed to be monitored will be as per the existing

EPN 8121/2 Attachment 2 and as shown in table below.


Table 22 Effluent Quality Sampling Parameters

Parameter Units Sampling Frequency

pH Monthly from the point of discharge

Temperature oC

Dissolved Oxygen mg/L

Turbidity NTU

Electrical Conductivity µs/cm

Total Suspended Solids mg/L

Ammonia Nitrogen mg/L

Nitrate mg/L

Nitrite mg/L

Total Nitrogen mg/L

Total Phosphorous mg/L

Thermotolerant coliforms cfu/100mL

Enterococci cfu/100mL

Blue-green algae Cells/mL

Total1 metals (As, Ba, Be, Cd, Cr, Co, Cu, Mn, Ni, Pb, V, Zn, Hg, and Al) Note – samples collected to allow for total and dissolved metal analysis. Samples analysed for total metals but retained at the laboratory to allow subsequent dissolved metals analysis should results for total metals exceed trigger values.

µg/L Annually from the point of discharge

1 In the instance that total metals ANZECC 95% toxicant trigger values are exceeded BLW will conduct dissolved metals for those parameters.


5.2.2 Plume Verification Sampling

A plume verification sampling event is to be undertaken during the commissioning phase to

validate the mixing assessment. The degree of mixing will be detected by measuring suitable

physicochemical tracers at sites around the outfall. Background data suggests conductivity as

the most suitable tracer owing to the notable difference between effluent discharge water

(median 446 µS/cm) and receiving environment (80th percentile downstream of Liffey river

77µS/cm). pH and DO may also be considered as a suitable tracer. If conductivity or other

physicochemical tracers are found not to be suitable as a tracer, rhodamine dye tracer will be

used as a proxy tracer.

In order to determine worst case mixing conditions, the plume verification sampling event is to

be completed during discharge to low river flow conditions (i.e. Autumn).

The timing for this plume verification monitoring is likely to be in April 2015 (autumn flows),

following the pipeline construction.

5.2.3 Ambient Water Quality Monitoring –Meander River

A tailored ambient monitoring program has been developed (Appendix M) to estimate, monitor

and characterise the receiving environment and assess the impact from the proposed new

discharge location. The monitoring program will be conducted in accordance with the relevant

standards and the standard operating procedures. The ambient monitoring program designed is

proposed to be implemented for a one year period after which time the results will be reviewed

and changes made to the monitoring as appropriate.

Sample Locations

Overall three locations will be sampled to assess the impact of the current discharge water.

These three locations are as follows:

One site on the Meander River, upstream of the Liffey River confluence (P1), upstream of

effluent discharge.

One site at the proposed discharge location on the Meander River (at the edge of

expected mixing zone) (P3).

One site downstream of the proposed discharge location at Westwood Bridge

(downstream of the toxicant mixing zone and at a location that will represent homogeneity

in terms of nutrient mixing) (P4).

Refer to Figure 16 for sample monitoring locations.

Sample Parameters and Frequency

The sample parameters of the ambient water monitoring program are linked to the system

stressors and PEVs of the system, as summarised in Appendix M.

The sample parameters to be sampled as part of the recommended ambient monitoring plan

are as shown in the Table 23 below.

Potential for discharge from surface water drains will be taken into account when scheduling

ambient water sampling and when analysing ambient water results.

It is anticipated that local intermediate WQOs should be established after the outfall relocation

based on 12 months data from the upstream monitoring location P1. These WQOs will inform a

Discharge Management Plan for Carrick STP at a later date.

The monitoring of the upstream site (P1) has commenced and there are currently 8 results

available (including only 4 contiguous monthly results). Consideration could be given to ceasing

monitoring from the upstream site following collection of 12 consecutive monthly results.


Attention will be paid to ensure that the LOR for analysis of nutrients is sufficiently low to allow

use of the data for derivation of intermediate WQOs.

Table 23 Water Quality Sampling Parameters

Parameter Units Sampling Frequency

pH Monthly during discharge for P3 and P4, monthly for upstream site (P1) Temperature oC

Dissolved Oxygen mg/L

Turbidity NTU

Electrical Conductivity µs/cm

Total Suspended Solids mg/L

Ammonia Nitrogen mg/L

Nitrate mg/L

Nitrite mg/L

Total Nitrogen mg/L

Total Phosphorous mg/L

Dissolved reactive phosphorous mg/L

Thermotolerant coliforms cfu/100mL

Enterococci cfu/100mL

Chlorophyll-a µg/L Monthly (October – May)

Blue-green algae Cells/mL

Total2 metals (As, Ba, Be, Cd, Cr, Co, Cu, Mn, Ni, Pb, V, Zn, Hg, and Al) Note – samples collected to allow for total and dissolved metal analysis. Samples analysed for total metals but retained at the laboratory to allow subsequent dissolved metals analysis should results for total metals exceed trigger values.

µg/L Annually

2 In the instance that total metals ANZECC 95% toxicant trigger values are exceeded BLW will conduct dissolved metals for those parameters.


5.2.4 Biological Monitoring

A proposed biological monitoring plan is provided as part of the ambient monitoring plan in

Appendix M.

In total, four sites will be sampled within the vicinity of the proposed Meander River discharge

location. Two sites are located upstream of the proposed discharge location, with the remaining

two sites are located in the proposed downstream receiving environment, as follows:

One site on the Meander River, upstream of the Liffey River confluence.

One sites on the Meander River downstream of the Liffey River confluence and upstream

of the proposed outfall location.

Two sites downstream of the proposed discharge location one riffle habitat at river bend

and one at Westwood Bridge.

In order to account for the seasonal variation of invertebrate fauna AUSRIVAS recommends

spring and autumn sample periods.

At each site, a riffle (where possible) will be sampled using a 250 micron macroinvertebrate

sweep net. All samples will be live picked in the field in accordance with Tasmanian AUSRIVAS

methodology, and taken back to the laboratory for analysis.

All macroinvertebrates will be identified and enumerated in accordance with the Tasmanian

AUSRIVAS method. Macroinvertebrate data will be analysed using a number of macro

invertebrate indices, (i.e. AUSRIVAS, SIGNAL, EPT, Number of Families, Number of

Individuals) to assess the response of macro invertebrate communities to the discharge.

Monitoring of chlorophyll-a (biomass and % algae cover) will also be included in future biological

monitoring events.

S1

S2

S4

S3

P4

P3

P2

P1

Meander River

Liffey

River

500,546

500,546

501,046

501,046

501,546

501,546

502,046

502,046

502,546

502,546 5,401,

738

5,402,

238

5,402,

238

5,402,

738

5,402,

738

5,403,

238

5,403,

238

5,403,

738

5,403,

738

5,404,

238

5,404,

238

Figure 16G:\32\17413\GIS\Maps\Working\32_17413_15_Carrick_DPEMP_Monitoring_RevB.mxd

0 100 200 300 400 50050m

©2012. Whilst every care has been taken to prepare this map, GHD (and Google) make no representations or warranties about its accuracy, reliability, completeness or suitability for any particular purpose and cannot accept liability and responsibility of any kind (whether in contract, tort or otherwise) for any expenses, losses, damages and/or costs (including indirect or consequential damage) which are or may be incurred by any party as a result of the map being inaccurate, incomplete or unsuitable in any way and for any reason.


32-17413

Date 07 Oct 2014

Ben Lomond WaterCarrick WWTP DPEMP

Carrick Ambient Monitoring PlanProposed Monitoring Locations

Data source: Google Earth Pro, Satellite Imagery, 2013; GHD, Locations, 2012. Created by: jtoregan, Created by jtoregan, updated by dtickner.



Scale at A4 - 1:12 000

Drainage Line to Liffey River

Pump Station &Irrigation Take Off

Point

Proposed Outfall

Location

STP StorageDam (Inside Ben Lomond Water

Property)

Meander Valley Hwy


Meander River

Carrick


Liffey/MeanderRiver Confluence

Moat PropertyResidence

Drainage Line to Meander River

Westwood Road

ExistingEmergency

IrrigationArea

LEGEND

Proposed Aquatic Monitoring Site

Proposed Surface Water Monitoring Site

Proposed Pipeline

Private Access Road

Public Road

STP Boundary

Moat Property Boundary

Existing Drainage Line

River Irrigation Area


5.2.5 Annual Reporting

Annual reports will be prepared to report on the sampling programs outlined in this Section 5. In

particular annual reports will include summaries of:

Volumes of effluents discharged to receiving waters.

Ambient water quality, up and downstream of the outfall, compared against the baseline

upstream and downstream data and at the downstream extent of mixing zone.

Aquatic ecology survey, outline any changes from the baseline survey which may suggest

an impact from the outfall.

Monitoring data effluent water quality.

Outline of any incidents, complaints or notifications during the year.

Annual reports will be submitted to the Director within three months of the end of the reporting

period. The first reporting period will commence upon commissioning of the outfall.

Commitment 10 Undertake effluent and ambient monitoring in accordance with Sections 5.2.1 to 5.2.5 if this DPEMP


6. Decommissioning and RehabilitationA draft decommissioning and rehabilitation plan (DRP) will be prepared within 30 days of

notifying the Director of any decision that is likely to give rise to the temporary or permanent

cessation of activity, as outlined in the existing EPN No. 8121/2 (r1) (23 September 2011).

Whilst the existing Carrick STP is operating under EPN No. 8121/2(r1), it is anticipated that a

new EPN for the STP will soon be issued to include the proposed discharge location. Under

EPN 8121/2 Schedule 2 (DC3), the below is required with regards to rehabilitation following

cessation:

Following permanent cessation of the activity, unless otherwise approved in writing by the

Director, the land must be rehabilitated including:

1. The stabilisation of any land surfaces that may be subject to erosion; and

2. The removal or mitigation of any environmental hazards or land contamination that

might prose an on-going risk of causing environment harm; and

3. The decommissioning of any equipment that has not been sold or salvaged.

Where a DRP has been approved by the Director, rehabilitation must be carried out in

accordance with that plan.

Accordingly, the above requirements for decommissioning and rehabilitation will be adopted for

the proposed new discharge location and for the decommissioning and rehabilitation of the

existing discharge location.

The drainage channel to the Liffey River will be decommissioned by leaving it to return to its

natural state as a surface drainage line.


7. CommitmentsThe commitments presented in Table 24 relate to relevant management measures detailed

throughout Section 4 and Section 5 of this document.

Table 24 Commitments Table

No. Commitment Section

Reference

Timeline Responsibility

1 Develop a CEMP to address the

potential impacts on surrounding

waterways during the construction

of the pipeline and outfall. All

outfall construction works will be

undertaken in accordance with the

DPIWE Manual for Works in

Waterways and Wetlands (2003).

4.2.3 Pre-

construction

TasWater

2 Construct the effluent outfall

pipeline to the middle of the

Meander River using a four port

outlet at a depth 1m below the

surface to maximise mixing and

dispersion and verify the mixing

zone.

4.2.4 Pre-

construction

TasWater

3 Undertake routine effluent

monitoring, ambient monitoring and

a plume verification monitoring

event in the Meander River in

accordance with an EPA approved

ambient monitoring plan.

4.2.4 Operation TasWater

4 Maintain a system of operating

controls to maximise discharge,

while maintaining mixing zone,

during high flow conditions, and

avoiding discharge during flow

conditions including the provision of

remote alarms to detect control

valve failures


5 Maintain preventative pipeline and

telemetry system maintenance via

routine inspection.


6 Management of effluent containing

BGA in accordance with

TasWater’s Blue Green Algae

Prevention Control and

Management Plan Dec 2011,

including monitoring of BGA in

accordance with Section 5.2



No. Commitment Section

Reference

Timeline Responsibility

7 Undertake improvements to the

Carrick STP to ensure that future

effluent complies with EPN limits.


8 A Contingency Management Plan

for the Carrick New Pipeline and

Outfall will be developed prior to the

scheme commencing.


9 The Carrick STP Operations

Manual will be updated (where

required) within 4-6 months

following the commissioning period.


10 Undertake effluent and ambient

monitoring in accordance with

Sections 5.2.1 to 5.2.5 if this

DPEMP



8. ConclusionThe proposed new discharge pipeline and outfall aims to improve the current management

practices at the Carrick STP by improving the mixing of current effluent in the receiving waters.

The key environmental issues include the possible impacts upon water quality in the Meander

River arising from the proposed new effluent outfall.

The proposed new discharge pipeline and outfall has been designed to meet the objectives of

Commonwealth, State and planning policy and legislation.

With the proposed new outfall at the centre of the river with a four port outlet the impacts on the

water quality of the Meander River will be minimised, with a mixing zone of less than 1 m

expected for discharge during median river flows of autumn, winter and spring to meet the

EPA’s drafted site specific water quality objectives. No discharge of effluent is expected in

summer months or 7Q10 conditions, due to the presence of a 25 ML storage dam, which can be

used to store effluent and hold until river flow conditions improve.

During the irrigation season, little to no discharge of effluent is expected. Suitable contingency

measures in the form of controlled discharge or contingency dam storage are available to

control the impact of discharge during these times if required.


9. ReferencesAK Consultants (December 2009) Soil Analysis “The Moat” Carrick.

AJ North and Associates (May 2001) Botanical survey and fauna habitat assessment of

proposed sites.

ANZECC & ARMCANZ (2000) Australian and New Zealand Guideline for Fresh and Marine

Water Quality.

Ben Lomond Water (14 December 2011) Blue Green Algae Prevention Control and

Management Plan.

Ben Lomond Water (October 2011) Occupational Health and Safety Policy.

Ben Lomond Water September 2012 Annual Environmental Return Carrick STP 2011-2012.

Ben Lomond Water August 2010 Annual Environmental Return Carrick STP 2009-2010.

Ben Lomond Water, 2010, Carrick Wastewater Treatment Plant Effluent Re-use Scheme

DPEMP.

Ben Lomond Water, 2012, Carrick Wastewater Treatment Plant Manual.

Bureau of Meterology (cited as BOM). Available online at: http://www.bom.gov.au (accessed

October 2014).

Australian Bureau of Statistics Census Quick Stats 2011.

http://www.censusdata.abs.gov.au/census_services/getproduct/census/2011/quickstat/SSC600

52?opendocument&navpos=220) (accessed 23/10/12 and 20/10/12).

CEE Consultants (July 2002) Development Proposal and Environmental Management Plan

Carrick STP Reclaimed water use.

DPIWE (2002) Environmental Guidelines for the use of Recycled Water in Tasmania.

DPIWE (2003) Manual for Works in Waterways and Wetlands.

EPA 2001. Emission Limit Guidelines for Sewage Treatment Plants that Discharge Pollutants in

Fresh and Marine Waters, 2001.

EPA Tasmania (September 2012) Carrick Wastewater Treatment Plant Upgrade DPEMP

Guidelines, 3.

EPA Tasmania (2013a) Draft Water Quality Objectives and Biological Condition Objectives for

the Meander River at Strathbridge.

EPA Tasmania (2013b) Draft Water Quality Guidelines and Biological Condition Objectives for

the Meander River Adjacent to the proposed Carrick WWTP Outfall.

GHD (August 2012). Report for Greater Launceston Wastewater Strategy (2010-2060) –

Additional GLWS Study Works.

GHD (September 2012) Report for Greater Launceston Wastewater Strategy Phase 2 land

suitability assessments – potential new northern Hadspen STP sites.

GHD (October 2014) Carrick STP Partial Effluent Reuse Environment Report

Grose C.J. and Moreton R.M, (1996), South Esk Report, Land Capability Survey of Tasmania

DPI.

LISTmap www.thelist.tas.gov.au (accessed September 2014).


R. Sainty (May 2001) Aboriginal cultural heritage survey of Meander Valley East Devonport and

Meander Valley.

Serve Ag (March 2001) Soil Survey and Effluent Reuse Suitability Report for the Moat Property.

Sloane GeoScience. (Dec 2012) Carrick Reuse Scheme Groundwater Monitoring plan.

Sloane GeoScience. (Dec 2011) Carrick STP Groundwater Monitoring plan December 2011.

Sloane GeoScience (2009) Carrick STP groundwater monitoring results 2009.

Meander Valley Council Carrick, Northern Tasmania

http://www.meander.tas.gov.au/page.aspx?u=491 (accessed 23/10/12).

NHMRC & NRMMC (2011) Australian Drinking Water Guidelines 6, 2011.

NHMRC (2008) Guidelines for Managing Risks in Recreational Water 2008.


10. AssumptionsThis report: has been prepared by GHD for TasWater and may only be used and relied on by

TasWater and the EPA for the purpose agreed between GHD and the TasWater as set out in

the Section 1 of this DPEMP.

GHD otherwise disclaims responsibility to any person other than TasWater arising in connection

with this DPEMP. GHD also excludes implied warranties and conditions, to the extent legally

permissible.

The services undertaken by GHD in connection with preparing this DPEMP were limited to

those specifically detailed in the report and are subject to the scope limitations set out in the

report.

The opinions, conclusions and any recommendations in this DPEMP are based on conditions

encountered and information reviewed at the date of preparation of the report. GHD has no

responsibility or obligation to update this DPEMP to account for events or changes occurring

subsequent to the date that the report was prepared.

The opinions, conclusions and any recommendations in this DPEMP are based on assumptions

made by GHD described in this DPEMP (refer to section 4 of this DPEMP). GHD disclaims

liability arising from any of the assumptions being incorrect.

GHD has prepared this DPEMP on the basis of information provided by TasWater and others

who provided information to GHD (including Government authorities), which GHD has not

independently verified or checked beyond the agreed scope of work. GHD does not accept

liability in connection with such unverified information, including errors and omissions in the

report which were caused by errors or omissions in that information.

Appendices

Documents

TasWater - epa.tas.gov.au · GHD | Report for TasWater - Carrick STP New Discharge Pipeline and Outfall , 32/17413 | i Foreword The overall objective of the Environmental Management