UNCLASSIFIED

DEPARTMENT OF DEFENCE ENVIRONMENT AND ENGINEERING BRANCH

DIRECTORATE OF CONTAMINATION ASSESSMENT, REMEDIATION AND MANAGEMENT

Contamination Management Manual

Annex C Planning to Minimise and Manage Stockpiling

March 2018, Amended June 2021

UNCLASSIFIED

UNCLASSIFIED i

© Commonwealth of Australia 2018 This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from the Australian Government Department of Defence. Announcement statement—may be announced to the public. Secondary release—may be released to the Australian Government Department of Defence, its contractors and their equivalents in United States of America, Canada, New Zealand and Great Britain. All Defence information, whether classified or not, is protected from unauthorised disclosure under the Crimes Act 1914. Defence information may only be released in accordance with the Defence Security Manual as appropriate. First edition 2018 Sponsor Directorate of Contamination Assessment, Remediation and Management Developer Directorate of Contamination Assessment, Remediation and Management Issued by Assistant Secretary Environment and Engineering Branch

Effective Date March 2018

Amendment Date June 2021

Review Date June 2022 or when changes to processes require an update Amendments to the document can be proposed as required. Proposals for amendment of this document are to be forwarded to: Director of Contamination Assessment, Remediation and Management Email: ncrp@defence.gov.au

UNCLASSIFIED

UNCLASSIFIED ii

Quick Reference Guide Why is this an issue for Defence?

Mandatory requirements The following requirements are mandatory when undertaking construction, demolition and excavation activities where excess soil may be generated, and/or existing stockpiles are located within the project area:

Defence Projects must demonstrate alignment with the Defence Environment and Heritage Manual, Chapter 12: Waste Minimisation and Management, and the Defence Smart Infrastructure Handbook, and seek opportunities to re-use excess soil on-site as the preferred waste management option from a cost, sustainability and capability perspective.

Projects that create stockpiled soil are responsible for managing their stockpiles to a suitable agreed end point (e.g. beneficial re-use or disposal off-site) and up to the end of the defects liability period.

All stockpiles must be managed and tracked in accordance with the project Construction Environmental Management Plan (CEMP) and, where required, in accordance with an Environment Clearance Certificate (ECC).

Stockpiling of excess soil is to be used only as a short-term (or temporary) management measure (i.e. for a period up to 2 years).

Projects that create any form of stockpiled excess solid material have responsibility for all stockpiles created by their project, regardless of the contamination type. Projects handing over stockpiles as part of HOTO must specify maintenance activities and funding source.

No material can be added to existing stockpiles without the approval of regional environmental personnel.

HSE Risk

Health, safety and environmental risks may arise from the presence and/or reuse of potentially contaminated stockpiled soil, depending on the nature, extent and concentration of the contaminant and the exposure pathway.

Commercial Risk The reuse on-site, or disposal or reuse-off site, of potentially contaminated stockpiled soil without first understanding its contamination status may expose Defence to a future clean-up liability and reputational risk.

Defence Capability

Project delays and remediation costs associated with inappropriately managing potentially contaminated soil stockpiles can have a significant impact to Defence capability and operations.

UNCLASSIFIED

UNCLASSIFIED iii

Sampling for soil characterisation and waste classification is preferred in-situ prior to disturbance. Additional sampling may be necessary prior to commencing a project to further determine contamination status of the excess soil and / or status of an area where excess soil is to be temporarily stockpiled.

If a contaminated stockpile is to be retained for a duration of greater than 2 years, it must be contained in an appropriately engineered storage structures at a location approved by a Site Selection Board and identified through the assignment of an Estate asset number as a waste storage structure, with management of the excess soil and end-point plans documented in the Hand Over and Take Over (HOTO).

A contaminated stockpile that is to be retained for a duration of greater than 2 years is considered as long term storage and a GEMS EFM-CSR must be recorded in GEMS and linked to the waste storage structure Estate asset number. The GEMS EFM-CSR must be submitted with relevant documentation (e.g. Contamination Risk Assessment Tool (CRAT) risk output, and ongoing risk management as part of HOTO) regardless of whether the waste storage structure is lined or encapsulated.

More information Directorate of Contamination Assessment, Remediation and Management (DCARM) at

ncrp@defence.gov.au

Defence PFAS Investigation and Management Program

Assistant Directorate Environment and Sustainability (ADES) or Defence Environment and Sustainability Manager (ESM)

UNCLASSIFIED

UNCLASSIFIED iv

Table of contents Quick Reference Guide ............................................................................................................................ ii

Abbreviations ........................................................................................................................................... vi

1. Introduction..................................................................................................................................... 8

1.1 Background .......................................................................................................................... 8 1.2 Purpose ................................................................................................................................ 9

1.3 Defence documentation ....................................................................................................... 9

2. Regulatory Overview .................................................................................................................... 10

2.1 Overview ............................................................................................................................ 10 2.2 Defence Legal Obligations and Compliance Register ....................................................... 13

2.3 Contractual obligations ...................................................................................................... 13

2.4 Off-site migration ................................................................................................................ 13

2.5 Stockpiles and re-use of contaminated soil ....................................................................... 13

2.6 Sampling and analysis ....................................................................................................... 14

3. Contamination Risk Management-Business Processes .............................................................. 15 3.1 Estate governance and integrity system ............................................................................ 15

3.2 The Smart Infrastructure Handbook .................................................................................. 15

3.3 The Estate lifecycle – Plan, develop and deliver stockpile minimisation and management ...................................................................................................................... 15

3.4 The Estate lifecycle – HOTO for stockpile management ................................................... 17

4. Conceptual Site Model and Stockpiling ....................................................................................... 20

4.1 Overview ............................................................................................................................ 20

5. Stockpile Contamination Assessment and Reporting .................................................................. 23

5.1 Overview ............................................................................................................................ 23 5.2 Orphan or legacy stockpiles .............................................................................................. 23

5.3 In-situ soil characterisation - Prior to disturbance .............................................................. 24

5.4 Ex-situ soil characterisation - stockpiled materials ............................................................ 25

5.5 Assessment of soil leachability .......................................................................................... 26

5.6 PFAS .................................................................................................................................. 26

5.7 Property transactions ......................................................................................................... 26 5.8 Asbestos ............................................................................................................................ 26

5.9 Approval process of on-site stockpile management .......................................................... 26

5.10 Tracking and recording waste storage structures .............................................................. 28

Stockpile ....................................................................................................................................... 29

6. Management ................................................................................................................................ 29

6.1 Overview ............................................................................................................................ 29

6.2 Protecting human health and the environment .................................................................. 29

6.3 Management options ......................................................................................................... 29

UNCLASSIFIED

UNCLASSIFIED v

6.4 Pollution prevention ........................................................................................................... 30

6.5 Case studies ...................................................................................................................... 31

6.6 Case study 1: Reuse or off-site disposal of excess soil and waste water from construction works ............................................................................................................. 32

6.7 Case study 2: Potential reuse of stockpiled materials on-site ........................................... 33

6.8 Case study 3: Reuse of PFAS impacted soil ..................................................................... 34

7. Data and Reporting ...................................................................................................................... 35

7.1 GEMS EFM – CSR ............................................................................................................ 35

7.2 Geographic information systems ....................................................................................... 35

7.3 ESdat ................................................................................................................................. 35

7.4 GEMS Estate asset record ................................................................................................ 36

8. Glossary ....................................................................................................................................... 37

9. References ................................................................................................................................... 39

Figure index Figure 1-1 Overview of Defence Environmental Documentation and Annex C .................................... 9

Figure 2-1 The Waste Hierarchy (National Waste Policy 2018) ......................................................... 14

Figure 3-1 Stockpile Management and the Estate Lifecycle ............................................................... 19

Figure 4-1 Contamination Risks Associated with Stockpiles and Reusing Contaminated Material .............................................................................................................................. 22

Appendices Appendix A – Checklist for Characterisation and Waste Classification of In-situ and

Stockpiled Soils

Appendix B – Management and Treatment Options

Appendix C – Soil Stockpile Risks and Mitigation Measures

UNCLASSIFIED

UNCLASSIFIED vi

Abbreviations

Abbreviation Meaning

ADES Assistant Director Environment and Sustainability

AGPS Australian Government Publishing Service

ANZECC The Australian and New Zealand Environment Conservation Council

ARMCANZ Agriculture and Resource Management Council of Australia and New Zealand

AS Australian Standard

ASC NEPM National Environment Protection (Assessment of Site Contamination) Measure 1999 (Cth) (NEPC 2013)

ASLP Australian Standard Leaching Procedure

CEMP Construction Environmental Management Plan

CEPA Commonwealth Environment Protection Agency

CoPC Contaminants of Potential Concern

CRAT Contamination Risk Assessment Tool

CSM Conceptual Site Model

CSR Contaminated Sites Record

DBC Detailed Business Case

DCARM Directorate of Contamination Assessment, Remediation and Management

DCMM Defence Contamination Management Manual

DEHPD Directorate of Environment and Heritage Policy Development

DELM Directorate of Estate and Land Management

DEPAC Directorate of Environmental Planning, Assessment and Compliance

DEQMS Defence Estate Quality Management System

DQO Data Quality Objective

DRN Defence Restricted Network

EBP Estate Base Plan

ECC Environmental Clearance Certificate

ECID Estate Class ID (Estate Asset identifier in GEMS)

EHM Environment and Heritage Manual

EPA Environmental Protection Agency or Environment Protection Authority

EPBC Act Environment Protection and Biodiversity Conservation Act 1999 (Cth)

ESM Environment and Sustainability Manager

EWP Estate Works Program

FIP Facilities Infrastructure Program

FRTR US Federal Remediation Technologies Roundtable

GDL GEMS Data Load

GEMS EFM – CSR

Garrison Estate Management System Environmental Factor Management – Contaminated Site Record (formerly referred to as the Contaminated Sites Register)

UNCLASSIFIED

UNCLASSIFIED vii

Abbreviation Meaning

GIS Geographic Information System

HEPA Heads of EPAs Australia and New Zealand

HOTO Handover/Takeover

HSE Health, Safety and Environment

IBC Initial Business Case

IERs Initial Environmental Reviews

IWRC Industrial Waste Reduction Centre

IWRG Industrial Waste Resource Guidelines

LOCR Defence Legal Obligations Compliance Register

NATA National Association of Testing Authorities

NEPC National Environment Protection Council

NEPM National Environment Protection Measure

NSIMS National Spatial Information Management System

PCA Pre-construction Contamination Assessment

PFAS Per- and Poly-Fluoroalkyl Substances

PFAS NEMP PFAS National Environment Management Plan V2 2020 (HEPA)

PFASIM PFAS Investigation and Management

QAQC Quality Assurance and Quality Control

RAAF Royal Australian Air Force

SA EPA South Australia Environment Protection Authority

SAQP Sampling and Analysis Quality Plan

SDMP Spatial Data Management Plan

SSB Site Selection Board

TCLP Toxicity Characteristic Leaching Procedure

UCL Upper Confidence Level

US EPA United States Environmental Protection Agency

UNCLASSIFIED 8

1. Introduction 1.1 Background

Project schedule and budget implications associated with the management of legacy and new stockpiling of excess contaminated materials is an on-going issue for Defence.

This Annex focuses on stockpile management of excess soils resulting from construction, demolition and excavation on the Estate. A stockpile refers to in this Annex is an ex-situ quantity of soil sourced from the same location and of the same type. It does not address landfill or uncontrolled waste sites which consist of different materials from multiple sites. Guidance on the management of new and legacy landfill sites is provided in Annex D of the Defence Contamination Management Manual (DCMM).

The most frequently stockpiled materials on the Estate are soil and sediment excavated during development or re-development projects or smaller construction activities. References to soil in this Annex hereafter includes sediment unless stated otherwise. Irrespective of the intended purpose of the stockpile or the type of solid waste being stockpiled, this document provides guidance on opportunities to avoid, minimise and manage stockpiling and explains the need to characterise materials early to determine their contamination and waste classification status, which with other factors, will inform management options.

Stockpiling is considered a temporary management measure by Defence. In this Annex, temporary stockpiling is defined as less than 2 years from the time of creating the pile. Stockpiling beyond 2 years must only occur on the Defence Estate when all other options are exhausted.

If a stockpile is to be retained for greater than 2 years from the expected creation time, Site Selection Board approval is required. Individual projects may also need to incorporate short term stockpiles into site selection approvals according to local land use pressures and Base planning requirements.

Note that the Per- and Poly-Fluoroalkyl Substances (PFAS) National Environmental Management Plan v2 (2020) (PFAS NEMP) also defines short term stockpiling as periods of less than 2 years. Refer to Annex K of the DCMM for the management of stockpiled soil impacted by PFAS.

In some circumstances, it may be necessary to stockpile soil before its contamination status is known. At some Defence sites, legacy contaminated stockpiled soil may also be present.

Once waste avoidance and minimisation measures are exhausted, and depending on the characteristics and waste classification, management options for temporary stockpiled material may include beneficial re-use, treatment and re-use, and disposal off-site or long term storage on the Estate. On-site re-use is the preferred option from a cost and sustainability perspective which is aligned with the Defence Environment and Heritage Manual (EHM) (Chapter 12: Waste Minimisation and Management) and the Defence Smart Infrastructure Handbook.

This document is to be used in combination with other contamination management tools that are discussed further in the DCMM.

UNCLASSIFIED 9

1.2 Purpose

The purpose of this document is to provide Defence personnel and its contractors with information on approaches to minimise stockpiling, the potential risks associated with stockpiles and how to manage potentially contaminated stockpiles resulting from construction, demolition and excavation activities.

1.3 Defence documentation

This guidance document is an Annex to the DCMM and supports compliance with site contamination management policy as detailed in the Defence EHM. An overview of where this Annex fits into the Manual is presented in Figure 1-1.

Figure 1-1 Overview of Defence Environmental Documentation and Annex C

UNCLASSIFIED 10

2. Regulatory Overview 2.1 Overview

Defence and its contractors must operate to comply with all Commonwealth legislation, including the Work Health and Safety Act (WHS Act), Environmental Protection and Biodiversity Conservation Act (EPBC Act) and the National Environmental Protection (Assessment of Site Contamination) Measures (NEPM). Reference can be made to the Defence Legal Obligations and Compliance Register (LOCR) which is designed to provide both guidance on environmental legal obligations and as a tool to manage compliance to these obligations.

Defence may not be subject to State and Territory law in all situations. Whether or not Defence is bound by State and Territory law is a complex issue and legal advice must be obtained to confirm whether a particular State or Territory law is applicable to Defence. Defence contractors must comply with relevant State or Territory laws.

Any interaction with State or Territory environmental regulators must only occur after first consulting the Directorate of Contamination Assessment, Remediation and Management (DCARM) at ncrp@defence.gov.au, and if applicable, the Environment and Sustainability Manager (ESM) and/or the Assistant Director Environment & Sustainability (ADES).

Guidance relating to the assessment of site contamination is outlined in the National Environment Protection Council (NEPC) 1999 (Cth), National Environment Protection (Assessment of Site Contamination) Measure (NEPM) as amended in May 2013 (ASC NEPM).

2.1.1 NEPM

The ASC NEPM was made under the National Environment Protection Council Act 1994 (Cth). It is the national guidance document for the assessment of site contamination in Australia. It is given effect by the National Environment Protection Measures (Implementation) Act 1998 (Cth) for the Commonwealth and individual legislation and guidelines in each State and Territory.

The NEPC agreed to vary the NEPM by approving an amending instrument to the ASC NEPM in 2013.

All assessments of site contamination on the Defence Estate are to be undertaken in accordance with the recommended process and guidance provided in the ASC NEPM.

The purpose of the ASC NEPM is to establish a nationally consistent approach for the assessment of site contamination; to ensure sound environmental management practices by the community, including regulators, site assessors, site contamination consultants, environmental auditors, landowners, developers and industry parties.

The desired outcome of the ASC NEPM is to provide adequate protection of human health and the environment, where contamination has occurred, through the development of an efficient and effective national approach to the assessment of site contamination.

The ASC NEPM and schedules are available for download through the NEPC website. The ASC NEPM Toolbox contains additional information including calculators, spreadsheets and other supporting documents to assist with application of the amended ASC NEPM.

Section 7.5, Schedule B2 of the ASC NEPM presents the minimum number of samples recommended for an initial assessment of soil stockpiles.

Section 7.5 of the NEPM Schedule B2 Guideline on Site Characterisation presents the methodology for sampling and characterisation of stockpiles.

UNCLASSIFIED 11

2.1.2 Commonwealth Work Health and Safety Act 2011

The WHS Act commenced in 2012 and is regulated by Comcare, a Commonwealth Government agency that works in partnership with the Safety, Rehabilitation and Compensation Commission. The WHS Act provides for a nationally consistent framework to protect workers and other persons against harm to their health and safety through the elimination or minimisation of the risks so far as reasonably practicable.

Under the WHS Act, employers must take all reasonably practicable steps to ensure the health and safety of its employees and those who are at or near a workplace under the employer's control. This means that Defence and its contractors have obligations to protect the health and safety of workers and others operating within the vicinity of contaminated land that is on or near to a workplace under Defence control.

Model Codes of Practice administered by Safe Work Australia provide practical guides to eliminate and minimise the risks to health and safety as required under the WHS Act.

Any controls outlined in the Defence Safety Manual (SafetyMan) must be implemented when managing contaminated materials.

2.1.3 Defence Environment and Heritage Manual

The Defence EHM (2019) describes the agreed approach to enabling Defence capability through long-term sustainable management of the environment. The EHM provides instruction and policy guidance for all Defence personnel and contractors on Defence’s legislative obligations and stewardship goals in line with the Defence Environmental Policy and Environmental Strategy 2016-2036.

The EHM is an administrative policy framework document that applies to all Defence personnel.

The EHM is divided into 13 chapters addressing:

Chapter 1 – Environment and heritage management in Defence

Chapter 2 – Environmental assessment and approval

Chapter 3 – Heritage management

Chapter 4 – Domestic biosecurity

Chapter 5 – Native species and communities

Chapter 6 – Soil management

Chapter 7 – Bushfire management

Chapter 8 – Pollution prevention

Chapter 9 – Site contamination management

Chapter 10 – Estate water management

Chapter 11 – Estate energy management

Chapter 12 – Waste and Sustainable Procurement

Chapter 13 – Estate climate adaptation

Each chapter links back to a Strategic Aim of the Defence Environmental Policy and provides supporting documentation for implementation of the policy.

UNCLASSIFIED 12

2.1.4 Environment Protection and Biodiversity Conservation Act 1999 (Cth)

The EPBC Act is the Australian Government’s central piece of environmental legislation. It provides a legal framework to protect and manage nationally and internationally important flora, fauna, ecological communities and heritage places, defined in the EPBC Act as matters of national environmental significance.

The EPBC Act protects:

• The environment, where actions proposed are on, or will affect Commonwealth land and the environment.

• The environment, anywhere globally on land and water, where a Commonwealth agency – including the Department of Defence – are proposing to take an action.

The nine matters of national environmental significance to which the EBPC Act applies are:

• World heritage properties

• National heritage places

• Wetlands of international importance (Ramsar wetlands)

• Listed threatened species and communities

• Listed migratory species

• Commonwealth marine areas

• The Great Barrier Reef Marine Park

• Nuclear actions (including uranium mining)

• A water resource in relation to coal seam gas development and large coal mining development

Defence uses a comprehensive environmental impact assessment and approval program to understand and manage the impacts of its activities on the environment and heritage, and to ensure compliance with the EPBC Act.

Under the EHM, the Directorate of Environmental Planning, Assessment and Compliance (DEPAC) is the Defence technical authority for determining compliance with the EPBC Act. All matters that may trigger the EPBC Act are to be referred to DEPAC at the DEPAC Projects inbox (eiginfrastructure.eedepaprojects@defence.gov.au).

DEPAC undertakes a self-assessment against the Significant Impact Guidelines 1.1 – Matters of National Environmental Significance and Guidelines 1.2 - Actions on, or impacting upon, Commonwealth Land and Actions by Commonwealth Agencies published by the Department of Agriculture, Water and the Environment to determine whether an action is likely to have a significant impact on a matter of national environmental significance protected by the EPBC Act

The self-assessment process considers the nature and extent of contamination and if the presence, disturbance, removal or remediation of existing contamination is likely to have a significant impact on EPBC Act protected matters. Where a significant impact to the environment is ‘likely’ the action must be referred to the Minister for the Environment to make a determination on whether a proposed action is a ‘controlled action’.

UNCLASSIFIED 13

2.2 Defence Legal Obligations and Compliance Register

Defence and its contractors must operate to comply with all Commonwealth legislation, including the WHS Act, EPBC Act and the NEPM. In addition, Defence and its contractors should be generally familiar with the legislative and other regulatory requirements associated with the site activities undertaken relevant to the State or Territory in which the site is located.

Contractors must comply with State and Territory laws where applicable. Reference can be made to the LOCR which is designed to provide both guidance on environmental legal obligations and as a tool to manage compliance to these obligations.

2.3 Contractual obligations

Contamination management stages that are undertaken on the Defence Estate and the Defence leased assets are to be conducted in accordance with existing Defence business processes as outlined in the DCMM, available on DEQMS and the GEMS Gateway.

All contractors undertaking contamination investigations, assessment and remediation projects are responsible for complying with these processes.

2.4 Off-site migration

The Defence Project Manager should obtain professional advice to inform the reporting and management of any contamination that is found to have migrated off-site into a State/Territory jurisdiction. Delineating the nature and extent of the off-site contamination will assist Defence to implement appropriate mitigation measures and to manage any legal implications. A link to the various State and Territory environmental agencies can be found in the DCMM.

Any interaction with State or Territory environmental regulators must only occur after first consulting DCARM at ncrp@defence.gov.au, and regional environment personnel.

Sites that are the subject of a current or previous PFAS investigations must only undertake any engagement with the State or Territory regulator in accordance with the agreed stakeholder engagement strategy for that site.

2.5 Stockpiles and re-use of contaminated soil

Contaminated soil, if not managed appropriately, has the potential to impact human health and the environment. It is best practice to adopt on-site stockpile management, including on-site treatment, re-use and containment to minimise the ecological footprint and the economic cost of soil management.

Re-use of contaminated materials, where such use does not have adverse impacts on human health and the environment, can prove to be highly beneficial from both an environmental and an economic standpoint (IWRC, 2003).

The Commonwealth Government’s National Waste Policy (2018) describes the Waste Hierarchy (Figure 2-1) as a set of principles for the efficient use of resources and management of waste materials. These principals can be applied to contaminated materials and are aligned with the aim of the Defence Smart Infrastructure Handbook.

UNCLASSIFIED 14

Figure 2-1 The Waste Hierarchy (National Waste Policy 2018)

The suitability of stockpiled soil for re-use as clean fill (or another beneficial use) either on-site or off-site is assessed on the basis of soil characterisation and waste soil classification performed by an appropriately qualified environmental consultant.

2.6 Sampling and analysis

The following national guideline documents provide information on the technical requirements for soil sampling and analysis for soil characterisation:

• NEPM (2013). Schedule B1 Guideline on Investigation Levels for Soil and Groundwater

• NEPM (2013). Schedule B2 Guideline on Site Characterisation • NEPM (2013). Schedule B3 Guideline on Laboratory Analysis of Potentially Contaminated

Soils

• AS 4482.1 (2005), Guide to the sampling and investigation of potentially contaminated soil, Part 1: Non-volatile and semi-volatile compounds

• AS 4482.2 (2005), Guide to the sampling and investigation of potentially contaminated soil Part 2: Volatile substances

• PFAS NEMP (2020). Section 18 PFAS sampling • Safe Work Australia (2016) Model Code of Practice: How to Safely Remove Asbestos

• Safe Work Australia (2016) Model Code of Practice: How to Manage and Control Asbestos in the Workplace

Different State/Territory sampling requirements for the classification of known and potentially contaminated soil for re-use and disposal vary. In addition to the above national guidelines, it is critical that prior to determining a sampling and analysis regime, project managers understand their specific State/Territory requirements for waste soil classification, particularly if off-site disposal is required.

UNCLASSIFIED 15

3. Contamination Risk Management-Business Processes 3.1 Estate governance and integrity system

Defence project managers and project contractors must consider the risk of contamination and management options at each stage of the Capability and Estate Lifecycle. The Estate Governance and Integrity System (EGIS) is the framework that will ensure the Defence Estate is compliant with regulations and industry standards and conforms with Defence policy.

It aims to assist in identifying and managing estate risks and hazards, while ensuring fit-for-purpose and compliant facilities that enable Defence capability and operations. Refer to the DCMM for further details on the application of EGIS across the Estate Lifecycle.

3.2 The Smart Infrastructure Handbook

The Smart Infrastructure Handbook (the Handbook) is the overarching ecologically sustainable development (ESD) and whole of life (WOL) guidance Defence applies across the Capability and Estate life cycles. It sets the minimum sustainability standards and requirement considerations for infrastructure planning, design and construction, as it relates to climate adaptation, estate energy, estate water, waste minimisation and management and pollution prevention.

Avoiding and minimising the production of excess solid waste materials such as soil for estate through to the design and construction phases of infrastructure projects are considered under Waste Minimisation and Management. The Handbook is supported by the Estate Planning checklist and the Design and Construction checklist as further discussed in Section 3.3.2.

3.3 The Estate lifecycle – Plan, develop and deliver stockpile minimisation and management

The EGIS and the Handbook provide the framework, guidance and opportunities to improve engagement and documentation on decisions associated with management of excess material from construction, demolition and excavation activities and reduce the need for stockpiling.

3.3.1 Site selection

The Site Selection Process is Defence’s procedure for approving the location of buildings, facilities and infrastructure across the Defence Estate. DCARM considers early engagement with the Site Selection Process will assist in early identification of contaminants of potential concern (CoPC) and risk mitigation and management options.

A contamination investigation and or a remediation project may be triggered by the Site Selection Process. Site contamination investigations may include one or more of the following:

• Pre-construction Contamination Assessment (PCA)

• Stage 1 Preliminary Site Investigation (PSI)

• Stage 2 Detailed Site Investigation (DSI)

UNCLASSIFIED 16

• Stage 4 Risk Assessment / Remediation Planning and Design, to identify and or delineate contamination

• Stage 5 Monitoring and Management

Technical guidance for each stage of the investigations can be found in Annex B of the DCMM.

The preferred approach for excess soil and stockpile management is to characterise soil and determine waste classification in-situ in the form of a PCA prior to disturbance. Ex-situ stockpile sampling may also be required if there are legacy stockpiles in the construction area (as further discussed in Section 5.2). In addition, baseline sampling may be necessary to understand the contamination status of a project area where excess soil is to be temporarily stockpiled.

3.3.2 Capital Facilities and Infrastructure Programs

Implementation of Smart Infrastructure by Capital Facilities and Infrastructure (CFI) programs is supported by the Estate Planning checklist and the Design and construction checklist. These checklists must be completed and submitted to Defence at each design stage of a project.

The Waste section of the Estate Planning checklist and the Waste Minimisation and Management section of the Design and Construction checklist set out the requirements that the project needs to consider to demonstrate that it has considered, addressed or implemented such requirements.

For further information on waste minimisation and management requirements in Estate Planning through to design and construction phases of a project, refer to the Handbook and the supporting checklists at DEQMS - Smart Infrastructure: Department of Defence.

3.3.3 Construction Environmental Management Plan

A Construction Environmental Management Plan (CEMP) is a site or project specific plan designed to ensure best practice and/or appropriate environmental management practices are applied throughout the construction, operation and/or demolition phases of a project.

Reference should be made to Chapter 4 of the Handbook for the minimum requirements of a CEMP to address waste management.

3.3.4 Estate Works Program

The Estate Works Program (EWP) are smaller in scope than CFI projects but cumulatively have the potential to create excess materials and substantial stockpiling (e.g. road grading and resurfacing). It is a Defence requirement that the applicability of Smart Infrastructure is assessed for projects within the EWP.

The EWP can include environmental projects delivered by Infrastructure Division (ID) and the Service Delivery Division (SDD), as well as property acquisition, disposal, expenditure or revenue leases delivered by Property Management Branch.

The Estate Maintenance Operations Services (EMOS) contractors deliver selected maintenance projects and Project Support Services through the EWP. EMOS must use the Hand Over Take Over (HOTO) Plan and checklist when delivering EWP projects.

Documentation for the implementation of Smart Infrastructure by the EWP is identified as part of the HOTO process, and include the use of the EWP Preliminary Assessment Matrix when scoping projects and completing the Scope and Feasibility report (phase 1), and the appropriate Smart Infrastructure elements are to be applied to Design Phase 2 for construction outcomes. Any decision to exclude the Handbook as a whole, or specific sections, requires justification.

UNCLASSIFIED 17

3.3.5 Environmental Clearance Certificates

Environmental Clearance Certificates (ECCs) form part of Defence’s environmental assessment and approval program. ECCs are used to regulate the conduct of Defence actions for the purpose of ensuring compliance with Commonwealth legislation, regulation and policies, most notably the EPBC Act. Project managers must be aware of Defences’ ECC obligations when considering, for example, the location and impact of ex-situ re-use of contaminated and non-contaminated materials.

3.4 The Estate lifecycle – HOTO for stockpile management

The Estate HOTO Policy (2020) ensures expected project outcomes are delivered and a structured and auditable approach to Defence accepting delivered project items is implemented. The HOTO policy ensures all estate related projects adhere to a systematic process which can demonstrate that project management practices, actions and deliverables comply with legislation, Australian Standards and Defence policy and instructions to deliver safe, compliant and fit for purpose facilities.

The HOTO process includes the HOTO Plan & Checklist, a Responsible, Accountable, Consulted, Informed (RACI) matrix and workflow diagram for use by the Project Director, project managers, project contractors and other key project stakeholders.

Use of the HOTO Plan checklist is not limited to E&IG. Defence entity such as Chief Information Officer Group (CIOG) and Capability Acquisition & Sustainment Group (CASG) use the HOTO checklist to achieve estate project outcomes.

The aim of the HOTO Plan & Checklist is to identify all documentary evidence required by Defence to demonstrate the delivered works are compliant, fit for purpose, safe and suitable for occupancy and use. It is used for all estate construction, maintenance, environmental and leasing projects delivering new or altering the existing Defence estate.

Examples from the HOTO checklist (v7), the associated checklist item numbers and the elements relevant to recording decisions associated with management of excess soil and other material, are identified below:

Design stage • Design initiation stakeholder engagement (Checklist item 2.0)

• Create Data Provision Checklist (Checklist item 2.1)

• Site Selection Board completed and approved (Checklist item 2.6)

Pre-mobilisation stage • CEMP or equivalent provided to Base and EMOS (Checklist item 3.2)

• Environmental Clearance Certificate (ECC -form AB081) and Environmental Management Plan (EMP) has been approved by the Zone ESO (Checklist item 3.6)

Construction stage • EMOS established maintenance and support (Checklist item 4.0)

HOTO stage

• ECC Post Activity Report submitted (Checklist item 5.26)

• Contamination Site Management Plan submitted, where relevant (Checklist item 5.28) • Data Provision Checklists completed for HOTO Phase (Checklist item 5.34)

• EMOS prepared for maintenance activities at DLP (Checklist item 5.35-5.36)

UNCLASSIFIED 18

DLP stage

• EMOS ready to commence agreed maintenance (Checklist item 6.3)

The HO is formalised by the contractor representative providing the required documentary evidence of project and estate information completion to the Project Director and Project Manager, who issue a completion certificate to the contractor representative.

The TO is confirmed by the Defence Representative being satisfied that all project deliverables are satisfactorily completed, the asset(s) is/are fit for purpose, evidentiary and Defence estate information requirements are met and signing the completed HOTO Plan and Checklist to that effect.

Figure 3-1 summarises the business processes involved in excess material and stockpile management, through the Estate lifecycle and referred to in this Chapter. Specifically the process steps in Plan stage of the lifecycle and the associated documents required at HOTO in the Deliver stage of the lifecycle.

UNCLASSIFIED 19

Figure 3-1 Stockpile Management and the Estate Lifecycle

UNCLASSIFIED 20

4. Conceptual Site Model and Stockpiling 4.1 Overview

As described in the ASC NEPM, a Conceptual Site Model (CSM) describes the contamination sources, pathways and receptors and the potential linkages between these.

An initial CSM can be constructed from the findings of a PCA, a Stage 1 PSI or a Stage 2 DSI (Refer to DCMM Annex B). The results from such sampling surveys are the basis for defining where potential source-pathway-receptor linkages may exist, and if further investigations are needed.

The CSM should identify complete and potential pathways between known or potential contamination sources and receptors. Where the pathway between a source and a receptor is incomplete, the exposure to chemical substances via that pathway cannot occur, but the potential for that pathway to be completed (for example, by abstraction of groundwater or a change in land use) should be considered in all stages of assessment.

The CSM can also be used to consider where management measures would reduce the likelihood of an exposure pathway becoming complete, such as the location and/or storage structure required for a temporary stockpile, i.e. less than 2 years.

The essential elements of a CSM are:

Known and potential sources of contamination and contaminants of concern including the mechanism(s) of contamination (e.g. ‘top down’ spill or sub-surface release from corroded tank or pipe)

Potentially affected media (e.g. soil, sediment, groundwater, indoor and ambient air)

Human and ecological receptors

Potential and complete exposure pathways

The CSM must be continually reviewed and updated throughout an ongoing assessment process to inform subsequent decisions on whether further investigation or contamination management actions are required. For contaminated land site investigation reports (e.g. Stage 2 DSI) the CSM is to be presented as a graphic, a table or flow chart and adequately described in written text.

4.1.1 Contaminants of potential concern

The CoPC at Defence sites may be broad ranging, as material can be sourced from any part of the site. It is necessary to determine the CoPC for each site on an individual basis due to the diverse nature of Defence activities and the range of potential historical uses across the Defence Estate.

In general, soils are considered potentially contaminated if they:

• Have been mixed with any wastes.

• Consist of, or partially consist of, soil of unknown origin that has been brought onto a site. • Arise from sites where former uses include industrial, commercial, mining or agricultural

activities.

• Have had manufactured chemicals applied. A review of the current and historical use of each site is necessary to determine which contaminants may be present. For example, if a site was historically used as a rifle range, lead

UNCLASSIFIED 21

would be considered one of the primary CoPC. However, where there are uncharacterised stockpiles, a broad analysis of CoPC is generally recommended where:

Little is known about the origin of the contaminated material.

The material appears to be mixed with other waste.

The material appears to be comprised of multiple soil types.

For further information on the CoPC associated with particular Defence activities, reference should be made to the DCMM.

4.1.2 Fate and transport

Depending on the solubility and persistence of the contaminants present in the stockpiled materials, contaminants may be mobilised from the stockpiles as a result of leaching and runoff into the immediate and surrounding environment, causing contamination of soil, sediment, surface water and/or groundwater.

4.1.3 Graphical conceptual site model and risk

A visual representation of a CSM relating to stockpiles and re-use of contaminated materials, and the potential contamination sources, pathways and receptors is presented in Figure 4-1.

While this figure depicts generic soil stockpiles, impacts from stockpiling of other forms of contaminated materials require similar considerations.

• Identifying the type and level of contaminant(s), e.g. characterisation and classification for soil/sediments

• Segregation and separation of materials, e.g. effective source management • Migration pathway management, e.g. surface water and sediment management

• Sensitivity of receptors - personnel on-/off-site and environment

The Defence Pollution Prevention Management Manual (PPMM) outlines management strategies for such materials as copper chrome arsenic (CCA) treated timber (Annex 1B), acid sulphate soils/sediments (Annex 1A), and residual heavy metal contaminated materials (Annex 1K).

UNCLASSIFIED 22

Figure 4-1 Contamination Risks Associated with Stockpiles and Reusing Contaminated Material

UNCLASSIFIED 23

5. Stockpile Contamination Assessment and Reporting 5.1 Overview

Stockpiles are the responsibility of the project or activity that creates them until an agreed end-point is realised. There are currently three management pathways through the Estate Project Planning and Design lifecycle for Projects unable to avoid generating stockpiles of excess soil.

1. The presence of stockpiles on the Estate, that are the result of historical activities, have been identified as having no Project owner, and are to be assessed and remediated where able.

2. Characterised and classified soil/sediment stockpiles with PFAS as the primary contaminant(s) of concern are to be assessed and managed according to DCMM Annex K, the PFAS Construction and Maintenance Framework and relevant PFAS policy advice.

3. With the exception of the above scenarios, for current and future projects unable to avoid or minimise excess materials, the following overarching principles apply:

Stockpiling of contaminated materials is considered a temporary management measure only, i.e. a short term solution of less than 2 years from the point of creation. Stockpiling timeframes and management must be specified in the CEMP (and/or ECC).

Stockpiles are the responsibility of the project or activity that created the stockpile and contractors are responsible for managing their stockpiles to a suitable agreed end point (e.g. re-use, treatment/re-use, containment on-site or disposal off-site) or up to the end of their defects liability period (DLP).

Stockpiling must not occur unless there has been consideration and agreement on the end point of the material, in consultation the Defence project manager and the Base Manager as per Joint Framework for Base Accountabilities (2019).

Re-use of excess excavated soil on-site is the preferred option from a cost, sustainability and capability perspective and is aligned with the waste management hierarchy set out in the Defence Environment and Heritage Manual, Chapter 12 and the Defence Smart Infrastructure Handbook.

Prior to determining the number of samples and sampling design for soil characterisation and waste classification, it is critical the relevant State/Territory environmental regulators are consulted. Different jurisdictions have different criteria and evidence requirements to demonstrate contamination. State/Territory environmental regulators are responsible for approving licences for transportation of waste and storage/disposal of waste at licenced waste disposal facilities.

5.2 Orphan or legacy stockpiles

Orphan or legacy stockpiles are waste piles left on Bases with no identified Project owner. Assessment of orphan or legacy contaminated or unknown composition stockpiled materials may be necessary to determine the risk status, management measures or waste classifications in anticipation of re-use or disposal. The assessment should follow the procedure for ex-situ soil characterisation as described at Section 5.4.

Where a Project is sited at an orphan stockpile location, provision must be made within the Project to adequately characterise and determine an end-point for the waste material, unless

UNCLASSIFIED 24

suitable arrangements can be made through the Service Delivery Division waste services contract.

Where an orphan or legacy stockpile is found to be contaminated, and there are no plans to treat, re-use or dispose of the waste, a GEMS – EFM CSR must be created according to the procedure provided in Annex L of the DCMM. No ESdat upload is required, unless the pile is unsealed and is a source of contamination into the environment.

5.3 In-situ soil characterisation - Prior to disturbance

In situ characterisation of soil, prior to construction, is Defence’s preferred approach on the basis this will assist Projects determine project footprints which may eliminate the need for stockpiling of contaminated materials and/or reduce the duration that stockpiles are present on-site (Figure 4-1). In addition, it may be necessary to conduct ex-situ stockpile sampling where there are legacy stockpiles in the vicinity of the construction area.

Characterisation of potentially contaminated soil must be conducted by consultants with proven relevant experience, such as the members of the Defence Infrastructure Panel – Environment, Heritage and Estate Engineering (DIP-EHEE) Contamination Management Service Category.

Sampling for chemical characterisation is undertaken to inform decisions on the materials end point and typically has three objectives:

• Waste classification – a waste classification of the soil to facilitate off-site disposal

• Treatment suitability – information to assist with an assessment of the potential for the soil to be successfully remediated to achieve the desired end point

• Suitability for re-use – assessment of the soil for re-use following excavation and treatment (if required)

Soils found to contain high concentrations of one or more contaminants must have mitigation measures included in the Project CEMP. Key considerations are options for the immediate off-site disposal of high concentration contaminated soils, or appropriate preparation of an agreed on-site location to take the contaminated soil until the permanent solution can be applied.

Selection of the chemical parameters for in-situ or ex-situ stockpile characterisation must be informed by a review of the Garrison Estate Management System Environmental Factor Management – Contaminated Site Record (GEMS EFM-CSR), historical data and consultation with regional Defence environmental personnel.

5.3.1 Soil characterisation and classification

Soil characterisation and classification typically involves four major components:

1. Develop a Sampling and Analysis Quality Plan (SAQP), including Data Quality Objectives (DQOs), appropriate sampling frequency and analytical suite, and spatial coverage to ensure that samples are representative of the entire stockpile

2. Collecting representative samples of the soil at an appropriate sampling frequency; in-situ pre-disturbance sampling needs to be in accordance with Australian Standard 4482.1. The density and design of sampling will relate to the site history, heterogeneity of the materials (e.g. fill, natural soil or rock) and presence of existing stockpiles. For existing stockpiles, sampling density must meet the minimum requirements detailed in Section 7.5 Schedule B2 of the ASC NEPM and with consideration to EPA Victoria (2009b) Industrial Waste Resource Guidelines: Soil Sampling (IWRG702).

3. Submitting the samples to a NATA accredited analytical laboratory for a suite of selected Contaminants of Potential Concern.

UNCLASSIFIED 25

4. Note the Quality Assurance and Quality Control (QA/QC) procedures, and where satisfactory, compare the analytical results to the appropriate State or Territory disposal regulations and environmental/human health criteria to determine the waste category and whether treatment of the soil is required prior to re-use or off-site disposal.

Appendix A provides an initial Checklist for Characterisation and Waste Classification of in-situ and stockpiled soils. It is important to refer to guidance in the ASC NEPM and EPA Victoria (2009b) on the number and design of in-situ and stockpile soil sampling. These references demonstrate the importance of sampling design and determining the adequate number of samples to meet the sampling objective, and highlight why it is important to use consultants with proven relevant experience.

If soil is to be re-used, it is important to consider not only the type and concentrations of contaminants present, but also the potential for these contaminants to leach from the soil through an assessment of leachability (Section 5.5). The soil and leachability analysis results can then inform decisions on re-use, treatment, storage or off-site disposal of the soil.

5.4 Ex-situ soil characterisation - stockpiled materials

Sometimes work commences without in-situ soil characterisation and classification. In addition to informing decisions on the materials end-point as noted above, ex-situ materials need to be characterised for assessment of potential risks to the health and safety of personnel and the environment in the project footprint or beyond Figure 4-1.

Stockpile characterisation and classification typically involves the same three major components as for in-situ soil sampling.

In accordance with ASC NEPM (2013), the following key tasks must be undertaken:

• Obtain available historical data and undertake site interviews to obtain background information, such as the origin, composition and age, of the stockpile – this will assist in identifying the CoPC for analysis once samples are collected.

• Excavate inspection slots/test pits into the stockpile noting the items listed in the checklist in Appendix A. These include visual and olfactory indicators of contamination and stockpile homogeneity. Smaller stockpiles can be excavated using a shovel. For larger stockpiles a excavator may be required.

• Undertake sampling at a frequency aligned with Section 7.5, Schedule B2 of the ASC NEPM.

• Composite sampling (combining samples collected from throughout the stockpile) should be considered where inorganic analytes are the CoPC. Composite sampling is not appropriate for assessment of volatile, or semi-volatile organic analytes.

As for in-situ sampling, if stockpiled soil is to be considered for re-use, it is important to understand the potential for contaminants to leach from the soil.

The EPA Victoria (2009b) guidance document, Industrial Waste Resource Guidelines: Soil Sampling (IWRG702), has guidance on the minimum number of samples for in-situ characterisation of soil and stockpile characterisation (based on volume) for reuse and worked examples of 95% UCL (normal distribution and log-normal data).

UNCLASSIFIED 26

5.5 Assessment of soil leachability

In an environmental context, leaching is the process of transferring chemical constituents from a solid particle to an aqueous solution. The leaching characteristics of soil can be used to select an appropriate landfill for off-site disposal of soil, and also to assess the suitability of soil for re-use (by assessing the potential for soluble contaminants to move through the soil and impact on groundwater).

With regard to the assessment of soil leachability, the following is highlighted:

• Leachability testing must be undertaken in accordance with the Australian Standard Leaching Procedure (ASLP) (AS 4439.2 and 44396.3) or Toxicity Characteristic Leaching Procedure (TCLP) (US EPA method 1311) by a National Association of Testing Authorities (NATA) accredited laboratory.

• When assessing soil for re-use typically a neutral leaching solution (~ pH 6.5 to 7) (e.g. deionised water) is used to simulate the pH of rainwater infiltrating the soil.

• When assessing soil for off-site disposal typically an acidic leaching solution (~pH 2 to 4) is used to simulate the pH of a landfill environment.

5.6 PFAS

The requirements relating to sampling, stockpiling and off-site disposal of PFAS impacted soil is outlined in the Defence PFAS Construction and Maintenance Framework and DCMM Annex K.

5.7 Property transactions

Adequate provision must be made for the characterisation and disposal management of existing stockpiles during the preparation of Defence property for disposal and leasing or when assessing properties for acquisition by Defence in order to minimise future liabilities. Refer to DCMM Annex A – Property Transactions, Redevelopment and Disposal for further information.

5.8 Asbestos

Under the Work, Health and Safety Act 2011 and regulations, the controllers of premises and/or employers have a duty to assess workplaces for the presence of asbestos and to document and communicate the condition of that asbestos to employees, contractors and visitors. This includes instances of potential asbestos containing material in stockpiles.

The Work, Health and Safety Regulations 2011 require the employer or controller to consult health and safety representatives and employees about asbestos presence, risk assessment and control measures (refer to Section 2 for legislative and regulatory requirements). The Base or Regional Asbestos Management Registers and Management Plans must be referred to when undertaking to manage legacy stockpiles. Consulting the Zone ESM/ESO, and GEMS Asbestos Register and CSRs, is also recommended.

Management of a stockpile is the responsibility of the project that created the stockpile regardless of the contaminant(s) within the stockpile. If a stockpile contains asbestos, the WHS officer must be consulted and the contractor/consultant engaged by the project MUST devise/specify the stockpile end-point and hazard control measures pending off-site disposal.

5.9 Approval process of on-site stockpile management

There are a number of reasons why the end-point for some stockpiled material is stored on Base for longer than 2 years. These typically include:

UNCLASSIFIED 27

• Where the soil does not meet the land use criteria (for human health and ecological protection, ASA NEPM, 2009)

• Contaminant concentrations are above acceptable levels for disposal to an off-site facility

• Due to the volume of material, distance and cost, landfill disposal or destruction are not viable options.

Where material will be stockpiled for periods greater than 2 years (or end of DLP), contractors must consult with the regional Defence environmental personnel to:

• Identify potential treatment options for any future re-use or off-site disposal and the funding sources to facilitate these strategies.

• Discuss Site Selection Board (SSB) approval. The SSB will consider a range of factors such as land constraints and impacts to Defence capability, and may determine that short-term stockpile locations must also be considered in the process.

• Agree on the engineering requirements for the waste storage structure. Any permanent solution will need to consider suitable siting criteria (e.g. depth to groundwater and sensitive human or ecological receptors) and associated design features such as lining/leachate collection system suitable for the CoPC and capping.

• Identify the risks associated with the chosen storage structure and management measures to prevent release of contamination in leachate, surface water run-off, sediment and dust. Pollution prevention measures must be documented in the CEMP and may include specifications for a liner system, overhead cover and bunding, and include prescribed stockpile dimensions.

• Where significant volumes of excess soil will be generated (e.g. >1,000 m3), record information setting out the sampling /analysis plan for soil characterisation, and identifying the end-point of the soil, and to be agreed within the CEMP.

• Identify the appropriate GEMS Estate Class ID and record Estate asset information such as: location, origin, material type, characterisation sampling results, volume, stockpile ownership status (responsible party), identified management end point and survey/scheduled monitoring timetable (Section 5.10).

• The HOTO process must include submission of a Stockpile Management Plan or equivalent, and a funding source for long term management activity such as capping inspections and maintenance.

• Where long term stockpiling of contaminated soils is likely (greater than 2 years), the waste storage structure must be added to the GEMS EFM – CSR as a contaminated site with the required documentation as per DCMM Annex L, and linked to the Estate Asset waste storage structure record. Note: DCARM does not require a CSR to be created where a waste storage structure holding contaminated material addresses pollution prevention controls, an agreed end-point has been documented and will be implemented within 2 years (i.e. a solution has been identified and can be implemented within a temporary timeframe).

• Asbestos contaminated waste must be disposed of off-site, except where disposal facilities are inaccessible. Where long term storage of soils containing asbestos is proposed, additional regulatory processes apply. In the first instance, refer to the Defence Asbestos Management Plan, and consult DCARM as early as possible.

UNCLASSIFIED 28

5.10 Tracking and recording waste storage structures

The Project responsible for generating stockpiles is to maintain records for the duration of the project sufficient to demonstrate compliance with the CEMP and/or ECC. Similarly, the Base must maintain a Register of all stockpiles held on Base longer than 12 months, in accordance with previous versions of this Annex. This requirement assists, for example, with tracking excess materials so separation of different source materials can be managed. This management strategy facilitates future re-use and treatment options, and can assist application of cost effective pollution prevention actions.

Base or Project Managers have the option to identify waste/excess material storage structures as an asset in GEMS so that information on location, volume, and survey/inspection schedules, can be readily recorded and tracked. The lodging of assets in GEMS can also facilitate mapping on GEO, be included on work schedules (where appropriate) and link to the GEMS EFM – CSR.

Where long term stockpiling is the agreed end-point (longer than 2 years), it is likely a partly sealed or encapsulated engineered facility will be constructed to store the excess contaminated materials. As well as being recorded as an asset, this location must be added to the GEMS EFM – CSR as a contaminated site with the required documentation as per DCMM Annex L. Refer also to Section 7 of this Annex.

UNCLASSIFIED 29

6. Stockpile Management 6.1 Overview

Storage or stockpiling must be undertaken only in suitable circumstances for genuine and beneficial purposes. The risks and potential impacts associated with stockpiling of impacted material are affected by a range of factors:

On-site risk factors associated with stockpiles include:

• Chemical and physical characteristics of the soil stockpiled and length of time materials will be stored

• Location and climate of the site

• Hydrogeology and hydrology including proximity to surface and groundwater

• Access for management and monitoring • Fire risk

Off-site risk factors associated with stockpiles include:

• Proximity to, and sensitivity of, the surrounding environment • Topography and hydrology elevation of the working level which the stockpile is situated

upon and relative to the surrounding environment

• Implementation of appropriate pollution control standards • Management of traffic in and around the site

A more detailed description of these risk factors and management measures, are presented in Appendix C Soil Stockpiles: Risks and associated mitigation measures.

6.2 Protecting human health and the environment

Before contaminated materials are re-used on a site, it must be demonstrated that the nature of the material to be re-used is appropriate to the present and proposed future use of the site. It is essential that where and how the material will be re-used and the potential risks that are associated with the proposed re-use are considered.

If a contaminated material has been removed from an area off site, this may be because of its potential to have a negative impact on human health and/or the environment. If the material is to be re-used, the associated negative impacts must be removed, or reduced to an acceptable level.

The impacts associated with the re-use of a contaminated material can be reduced by:

• Soil treatment prior to re-use to reduce the level of contamination in the material. This is the preferred method.

• Choosing suitable transport and storage facilities to reduce the risk of exposure to people and/or ecological receptors.

6.3 Management options

Sufficient information to inform the most appropriate management option for the material should be available following soil characterisation and waste classification. Examples of the potential management options for stockpiled materials include:

UNCLASSIFIED 30

• Separation

• Segregation • Disposal off-site

• Management ex-situ (storage)

• Re-use of soil on-site • Management in-situ

Treatment technologies may need to be considered to reduce contaminant concentrations to the levels that are suitable for the desired end-point (e.g. re-use or off-site disposal). Ex-situ treatment technologies may include:

• Biological treatment (e.g. biopiles or landfarming)

• Physical/chemical treatment (e.g. soil washing or stabilisation) • Thermal treatment (e.g. incineration or thermal desorption)

Examples of possible re-use scenarios, assuming the required chemical and geotechnical parameters are achieved, include:

• On-site under roadways/runways

• On-site under capped landscaping

• Off-site as fill material (although uncommon, where stockpiled material is proposed for use off-site)

Appendix B contains further information about the management options presented above.

6.4 Pollution prevention

All stockpiles and any storage structures must be managed in a way that minimises the potential for contamination to mobilise into the environment (refer to the Defence PPMM). Some general environmental management measures for the temporary stockpiling of contaminated soil are presented below with further information provided in Appendix C.

• Where possible, separate clean and contaminated excavated soil. – All site personnel must be made aware of the status of the stockpile(s) e.g.

clean/contaminated (refer to Project CEMP).

– Signage and inductions must assist personnel understand the importance of keeping materials with different contamination status separate.

– Any stockpile of contaminated or potentially contaminated material must be identified on a site plan/asset register. The stockpile should be identified with its source location, type of material, contamination status (e.g. awaiting classification), estimated volume, and the date it was stockpiled. This information must also be provided as part of HOTO.

• Material of unknown contamination status which is awaiting sampling must be contained (e.g. bunded and covered) and kept separate from other material until it has been characterised and classified.

• If contaminated or potentially contaminated material is to be stockpiled, appropriate waste storage is required to prevent potential leaching of contaminants into the soil and groundwater and to control surface water run-off (e.g. impermeable base/covers).

• All stockpiled materials must have a planned and agreed end-point and must not be stored beyond 2 years if it is chemically suitable for re-use, treatment and/or disposal.

• Appropriate sediment and erosion control measures must be implemented on the site.

UNCLASSIFIED 31

• The site must be secured, and access controlled to prevent additional dumping and non-project personnel entering the site.

• The Project must provide details of all stockpiles that will remain at the Defence base for periods greater than 2 years, such as:

– Demonstrate Site Selection Board approval, justification and agreement in the CEMP, and a funded management plan must be provided via HOTO.

– Identify the appropriate storage structure and establish the GEMS Asset record with management documentation.

– Create or update a GEMS EFM – CSR, as per DCMM Annex L, where a contaminated stockpile is to be retained for longer than 2 years, even if lined or encapsulated.

6.5 Case studies

The case studies presented in Sections 6.6, 6.7 and 6.8 highlight the contamination risks related to the management of stockpiles and re-use of contaminated materials on Defence land and identify management measures and sources of further information to address these contamination issues.

These case studies are hypothetical examples only and are not based on actual events.

UNCLASSIFIED 32

6.6 Case study 1: Reuse or off-site disposal of excess soil and waste water from construction works

6.6.1 Scenario

An underground service will be installed in a new 200 m service corridor on an active Royal Australian Air Force (RAAF) Base. Excavation of the trench and service pits will generate 500 m3 of excess material that may be contaminated. The contamination impact is associated with historical site activities (fuel storage).

The work area is constrained in size meaning excess material can only be temporarily stockpiled. The groundwater depth is shallow.

6.6.2 Risks

HSE – If contaminated material is encountered during excavation, construction workers may be exposed to an unacceptable HSE risk. If stockpiles are not managed correctly, an environmental pollution incident, via surface water run-off or dust, could occur.

Project Delays – If material is not suitable for re-use by reinstatement back in the excavation or at another location on the RAAF Base, the material will need to be disposed off-site requiring permits and approvals that cause project delays.

6.6.3 Key considerations and management measures

• Is an ECC required?

• Are there any known GEMS EFM-CSRs along the proposed excavation corridor to provide an indication of the type of contamination that may be encountered?

• Can sampling be conducted to characterise the soil/groundwater quality prior to excavation (this will assist in material segregation as not all contamination can be seen)?

• What is the likelihood that dewatering water will be generated and how will it be managed (disposal to stormwater/sewer or treated)?

• Does the RAAF Base have an area for temporary stockpiles? If no, where and how will the material be stored prior to reinstatement or off-site disposal?

• How will you document management decisions and track the movement of excavated materials from origin to final end-point?

• In most states and territories, waste classification is required to categorise the soil for off-site disposal. The legislative requirements for off-site disposal for contaminated soils may differ for each State/Territory.

6.6.4 More information

• Section 7.5 Schedule B2 of the ASC NEPM and EPA Victoria (2009) IWRG702 guidance which present the methodology for sampling and characterisation of stockpiles

• Defence Contamination Management Manual

• Defence Environment and Sustainability Manager (ESM) or Assistant Director Environment and Sustainability (ADES)

Why is this an issue? Construction works can generate contaminated waste soil/water causing significant delays to your project. There may also be an HSE risk to your site team and construction personnel.

How can I manage it? Prior to excavation: • Get information on

soil and water quality • Agree with Defence if

the soil can be reused or disposed off-site

More information • ASC NEPM Schedule

B2 • Defence

Contamination Management Manual

• ESM or ADES

UNCLASSIFIED 33

6.7 Case study 2: Potential reuse of stockpiled materials on-site

6.7.1 Scenario

An area of a Defence base is being developed as a military vehicle maintenance area. As a part of the development, a series of raised pads are required to be constructed on site. Appropriate stockpiled materials of a sufficient volume to construct the pads have been identified on site; however, the source, composition and age of the stockpiles are unknown.

6.7.2 Risks

HSE – If contaminated material is encountered within the stockpiled materials, construction workers and future site users may be exposed to an unacceptable HSE risk. If the stockpiled material is not characterised correctly and is inappropriately re-used, an environmental pollution incident, via groundwater contamination, surface water run-off or dust, could occur.

Project Delays – If the stockpiled material is classified as being contaminated and is subsequently not suitable for re-use on site, then the material will need to be disposed off-site. This process will require permits and approvals that can delay projects.

6.7.3 Key considerations and management measures

• Is an ECC required? • Are there any known GEMS EFR- CSR that may have been

excavated and stockpiled at the site to provide an indication of the type of contamination that may be encountered?

• Stockpile sampling density must meet the minimum requirements detailed in Section 7.5 Schedule B2 of the ASC NEPM and IWRG702 (EPA Victoria, 2009b).

• Samples must be collected according to AS 4482.1 and AS 4482.2 prior to excavation (this will assist in material segregation as not all contamination can be seen).

• Samples must be chemically characterised through laboratory testing and results compared to appropriate guidelines to determine if the material can be re-used on site.

• In most States and Territories waste classification is required to categorise the waste for off-site disposal. The legislative requirements for off-site disposal for contaminated soils may differ for each State/Territory.

6.7.4 More information

• Section 7.5 Schedule B2 of the ASC NEPM and EPA Victoria (2009b) IWRG702 guidance which presents the methodology for sampling and characterisation of stockpiles.

• Defence Contamination Management Manual

• ESM or ADES

Why is this an issue?

Reuse of stockpiles can mobilise contaminated soil and impact on surrounding sediment, groundwater and surface water, potentially causing environmental impacts and causing significant delays to your project.

There may also be an HSE risk to your site team and construction personnel. How can I manage it? Prior to reuse of stockpiled material: • Undertake a sampling

program to characterise the stockpiled material

• Agree with Defence if the soil can be reused or disposed off-site

More information • ASC NEPM Schedule

B2 and IWRG702 (EPA Victoria, 2009b

• Defence Contamination Management Manual

• ESM or ADES

UNCLASSIFIED 34

6.8 Case study 3: Reuse of PFAS impacted soil

6.8.1 Scenario

A new large-scale building is to be constructed at a Defence RAAF Base. During construction, large volumes of excess material from excavation of a basement carpark will be generated – it is proposed that the soil is re-used at the site or disposed off-site.

In consultation with the ESM or ADES, a PCA was scoped and implemented by a suitably qualified person. Low-level PFAS impact was identified in the soil proposed for re-use. Soil characterisation included sampling/analysis for totals (mg/kg) and leachability (mg/L). PFAS concentrations in the soil met Defence guidance on acceptable levels for commercial land use and the soil leaching potential was considered acceptable based on a site-specific CSM.

The soil was re-used within the project site under roadways and in landscaped areas - requirements for re-use included setbacks from drainage lines and waterways, maintaining a 0.5 m capping in re-use areas and on-going monitoring of the soil under a site management plan.

6.8.2 Risks

HSE – If soil proposed for re-use is not appropriately characterised prior to re-use, nor tracked or monitored during placement and re-use (e.g. using a site management plan), construction workers and future site users may be exposed to an unacceptable HSE risk.

There is the potential for HSE risks if impacted soil (PFAS or other) is transported out of the project site to a “clean” part of the Base during construction. Ex-situ management will need to be documented in D&C checklists.

Project Delays – Early engagement with the ESM or ADES, and potentially the PFASIM Directorate, to identify the process and site-specific requirements around re-use of impacted material to avoid delay projects (DCMM Annex K).

6.8.3 Key considerations and management measures

• As per Section 6.7.3 • Early engagement with the ESM or ADES, and if required the PFASIM Directorate, to map

out the process and site-specific requirements for re-use.

• Classification for re-use must consider total contaminants (mg/kg), leaching potential (mg/L) of the CoPC and potential source-pathway-receptor linkages through preparation of a site specific CSM.

6.8.4 More information

• Section 7.5 Schedule B2 of the ASC NEPM and EPA Victoria (2009b) IWRG702 guidance, which present the methodology for sampling and characterisation of stockpiles

• Defence Contamination Management Manual

• ESM or ADES and PFASIM Directorate

Why is this an issue? Reuse of stockpiles can mobilise contaminated soil posing a potential risk to your site team, construction personnel and the environment.

How can I manage it? Prior to reuse of material: • Engage with ESM or

ADES and if required the PFASIM Directorate

• Undertake a sampling program (PCA) to characterise the material. Total concentrations and leaching potential must be considered

• Agree with Defence if the soil can be reused or disposed off-site

More information • ASC NEPM Schedule

B2 • EPA Victoria (2009b)

IWRG702 • DCMM • ESM or ADES and

PFASIM Directorate

UNCLASSIFIED 35

7. Data and Reporting 7.1 GEMS EFM – CSR

Data and reports generated as part of the investigation and assessment of contamination must be captured in the GEMS EFM – CSR.

The GEMS EFM – CSR is the database used to capture environmental information across the Defence estate, and provides access to historical contamination investigation reports for Defence properties. Contaminated site records are geo-referenced and they can be accessed by Defence personnel or contractors with DPN access.

Contractors/Consultants working on behalf of Defence must provide reports, updated and completed GEMS Data Load Tool (GDL) (for new or existing CSRs), CRAT, ESdat and GIS files relating to contamination to their Defence point of contact, Project Manager, ADES or ESM who will be responsible for auditing and validating submissions and ensuring the upload of information into the GEMS EFM – CSR.

The creation of a GEMS EFM - CSR is mandatory for contaminated stockpiles held on Base for longer than 2 years, even where lined or encapsulated.

In the case of a pollution incident from a breach of either permanent or temporary storage facilities, the GEMS EFM - CSR will need to be amended with either an update to the storage facility CSR, or a new CSR created.

Where a contaminated stockpile is removed or treated such that it no longer poses a risk, the CSR can be archived by providing documentation in accordance with the DCMM Annex L requirements. Documentation can include validation or clearance certificates, sampling analysis conducted on treated soils and/or loading/landfill receipts.

Further guidance on upload of information into GEMS EFM – CSR, refer to DCMM Annex L – Data Management.

7.2 Geographic information systems

GEMS is geospatially enabled and within GEMS Estate data can be viewed via the Geo Explorer Module or opened via a GEO.e Tab for the individual CSR. Geo Explorer displays the boundary of a CSR and summary data from the CSR record.

The Projects Geospatial data must include all sampling locations and any resulting CSR boundary which is uploaded to E&IG National Spatial Information Management System (NSIMS). All spatial data supplied to E&IG must adhere to the standards and specifications described in the E&IG Spatial Data Management Plan (SDMP).

Refer to the DCMM Annex L – Data Management for further guidance on spatial data upload.

7.3 ESdat

The Defence ESdat is a specialist web based environmental data management software system that is used to validate, import, analyse and report a broad spectrum of environmental, physical, locational and meta-data. Data collected for contamination investigations, monitoring and management is uploaded and stored in ESdat from where it can be organised. Projects are required to establish a code for land sourced environmental contamination/validation sampling data so the chemical results can be uploaded to ESdat and made available to Defence personnel.

UNCLASSIFIED 36

Note: The data collected in ESdat represents contamination in the environment. Stockpiles are considered artificial waste storage areas separated from the environment through sealing or encapsulating, therefore, stockpile sampling information does not need to be uploaded to ESdat.

7.4 GEMS Estate asset record

Where contaminated material is to remain on Base for longer than 2 years it must be stored in a an appropriate storage facility. The specific type of storage structure will depend on the contaminants, site conditions and other factors.

The creation of an Estate asset record in GEMS is mandatory for a storage structure planned to hold contaminated material for longer than 2 years, making use of existing Estate Asset classes for waste storage structures. All stockpile sampling information must be recorded in GEMS, including any ongoing management requirements, and must be submitted by the Project through the HOTO procedures.

Depending on the contaminated material and the storage structure, a monitoring schedule may be required to ensure the facility is functional and fit for purpose.

Irrespective of the above mandatory requirement, Project Managers, Base Managers and ESMs/ESOs may make use of the GEMS Estate Asset Records to track, manage and monitor stockpiles and waste storage structures holding contaminated or non-contaminated material for any duration according to need and management preference.

Once a stockpile has been re-used on-site or disposed off-site, the GEMS Estate Asset Record must be closed out or decommissioned. Any documentation supporting the close out should be recorded, such as mapping of the re-use location or loading/landfill receipts.

UNCLASSIFIED 37

8. Glossary Term Meaning

BENEFICIAL RE-USE Re-use is the end-point of some excess contaminated materials. Beneficial re-use is a management strategy. Beneficial re-use is where the availability of the material for applications on Base or at another Defence site will be beneficial. The purpose of this strategy is to identify clearly in documentation where re-use is feasible and useful on Base. This will assist minimise stockpiles left after the completion of a Project/Activity on the basis of a future potential re-use option. If a beneficial re-use cannot be identified and implemented within 2 years from the time of stockpile creation, another management option will need to be identified.

CHARACTERISATION An assessment of the chemical and physical characteristics of the soil or sediment.

DEFECT LIABILITY PERIOD

Period where a defect is to be rectified by the contractor representative in accordance with the contract and agreed defect rectification plan.

END-POINT End-point refers to the final outcome for contaminated solid materials. It will either be left in-situ, re-used, stored or disposed. The decision to leave contaminated materials remain in-situ is uncommon but may occur where pre disturbance PCA and/or historical records suggest possible contamination. An end-point does not attempt to describe the variety of management options, pathways or destinations for the material. All end-points of excess materials, beneficial or not, should be identified by the Project/Activity creating them and responsible for their management to the final end-point. Agreement should be sort in the Project/Activity planning stage and documented in the CEMP/ECC and checklists supporting the HOTO.

GEOTECHNICAL Assessment of the characteristics of soil and/or rock as they may relate/impact on construction or other use.

ORPHAN STOCKPILE A stockpile older than 2016 where the responsible Project/Activity which created the stockpile is unknown or no longer accountable for the stockpiled materials final end-point. An orphan stockpile may have been generated in recent times from construction or demolition Project/Activity on the Estate and not necessarily from historic industrial or military activities.

LEGACY CONTAMINATION

Contamination caused by past industrial and military activities including uncontrolled landfilling and poor wastewater management. Legacy contamination may include orphan stockpiles.

SEGREGATION Segregation may be used interchangeably with separation. Often segregation relates to the characteristics of soil and/or the chemical components of contamination see NPEM s7 Stockpile Sampling.

SEPERATION Separation may be used interchangeably with segregation. Often separation of waste materials relates to physical distance/isolation of different waste material types.

UNCLASSIFIED 38

Term Meaning

SEDIMENT Sediment is made of the broken down remains of rocks, minerals, plants and animals that is moved and deposited to a new location.

SOIL Soil covers the upper layer of the earth in which plants grow. It is made up of solids, liquids and gases.

SOIL or SEDIMENT SLUDGE / SLURRY

Soil or sediment mixed with water as a result of construction or maintenance works which if contaminated requires the sludge/slurry to be dewatered and managed separately as solid soil or sediment and water.

SOIL STOCKPILE A quantity of soil removed from its known in-situ location.

WASTE CLASSIFICATION

The classification of waste materials into categories determined by State/Territory legislation that determines if materials are suitable for disposal to a Waste Management Facility. The legislative requirements for off-site disposal for contaminated materials including soils may differ for each State/Territory.

UNCLASSIFIED 39

9. References Australian and New Zealand Environmental Conservation Council (ANZECC) and Agriculture and Resource Management Council of Australia and New Zealand (ARMCANZ) (2000). Australian and New Zealand Guidelines for Fresh and Marine Water Quality, National Water Quality Management Strategy, Paper No. 4, Vol. 1, October 2000

CEPA (1992). National Waste Minimisation and Recycling Strategy. Commonwealth Environmental Protection Agency, AGPS. Canberra, 1992

Department of Defence (2009). Manual for the Management & Remediation of Petroleum Hydrocarbon Contaminated Soil and Sediments

Department of Defence (2019). Defence PFAS Construction and Maintenance Framework – Guidance for managing the risks of PFAS contamination for works on the Defence estate

Department of the Environment and Energy, The National Waste Policy: Less Waste, More Resources, 2018

EPA Victoria (2009a). Industrial Waste Resource Guidelines (IWRG) 701: Sampling and analysis of waters, wastewaters, soils and wastes. June, 2009

EPA Victoria (2009b). Industrial Waste Resource Guidelines (IWRG) 702: Soil sampling. June, 2009

IWRC (2003). Beneficial Re-use of Solid Wastes. Iowa Waste Reduction Center, University of Northern Iowa. August 2003

NEPC (2013). Schedule B1 Guideline on Investigation Levels for Soil and Groundwater, in ‘National Environment Protection (Assessment of Site Contamination) Measure 1999 (Cth) (as amended 2013), ASC NEPM, Commonwealth of Australia

NEPC (2013). Schedule B2 Guideline on Site Characterisation, in ‘National Environment Protection (Assessment of Site Contamination) Measure 1999 (Cth) (as amended 2013), ASC NEPM, Commonwealth of Australia

NEPC (2013). Schedule B3 Guideline on laboratory analysis of potentially contaminated soils, in ‘National Environment Protection (Assessment of Site Contamination) Measure 1999 (Cth) (as amended 2013), ASC NEPM, Commonwealth of Australia

SA EPA (2017), Guideline for stockpile management: Waste and waste derived products for recycling and re-use

Safe Work Australia (2016) Code of Practice: How to Safely Remove Asbestos

Safe Work Australia (2016) Code of Practice: How to Manage and Control Asbestos in the Workplace

Standards Australia (1997a). AS 4439.2: Wastes, sediments and contaminated soils. Part 2: Preparation of leachates — Zero headspace procedure (AS 44392: 1997)

Standards Australia (1997b). AS 4439.3: Wastes, sediments and contaminated soils. Part 3: Preparation of leachates —Bottle leaching procedure (AS 44393: 1997)

Standards Australia (2005a). AS 4482.1: Guide to the sampling and investigation of potentially contaminated soil, Part 1: Non-volatile and semi-volatile compounds (AS 4482.1: 2005)

Standards Australia (2005b). AS 4482.2 (2005): Guide to the sampling and investigation of potentially contaminated soil Part 2: Volatile substances (AS 448222: 2005)

UNCLASSIFIED

Appendices

UNCLASSIFIED

Appendix A – Checklist for Characterisation and Waste Classification of In-situ and Stockpiled Soils

UNCLASSIFIED

Table A-1 Checklist – Soil Characterisation and Classification1 Indicators for soil characterisation & classification Yes No

1. Visual Evidence of Contamination – are there any visual indications of chemical contamination (e.g. surface staining) on or in the soil and has adequate sampling/analysis been undertaken to determine the cause of the visual impact?2

□ □

2. Odours – are there any odours emanating from the soil and has adequate sampling/analysis been undertaken to determine the cause of the olfactory impact? □ □

3. Potentially Contaminating Activities – what type of activity has caused the generation of the soil, and does the activity have the potential to have contaminated the soil?

For example if the soil has been:

• Generated from the removal of a Underground Storage Tank (UST), a vehicle wash down bay or a drain near a mechanical workshop, then there is a high likelihood that the soil is contaminated; whereas

• Excavated on a Greenfield site, or a site where little historic activity has occurred, then there may be a low probability that the soil is contaminated.

□ □

4. Waste Soil from an Unknown Source – is the source of the soil / sediment known?

If the source of the soil / sediment is unknown then sampling and analysis of the material is advisable in order to assess the most appropriate option for the material.

□ □

5. Waste Classification – has adequate sampling and laboratory analysis been undertaken of the soil to assess the chemical composition, and determine a waste classification of the material3?

The sampling and analysis requirements, in addition to the categories of waste, vary between the states/territories.

□ □

6. Re-use of Material – has adequate sampling and laboratory analysis been undertaken of the soil to assess the chemical composition to determine whether the material is suitable for re-use on or off-site?

The land-use criteria (for human health and ecological protection) are provided in the National Environment Protection (Assessment of Contamination) Measure 1999 (Cth), as amended 2013.

□ □

7. If ex-situ remediation (i.e. excavation) is proposed, is there the potential for the soil to be Acid Sulfate Soils (ASS)?

Has any sampling been undertaken to confirm the absence or presence of ASS?

□ □

8. Remediation/Management Parameters – has adequate sampling and laboratory analysis been undertaken to characterise the key chemical and physical parameters of the soil to:

• Assess whether specific soil remediation methods are appropriate.

• Assess the suitability of the available management options (Monitored Natural Attenuation).

□ □

1 Based on the Department of Defence (2009). Manual for the Management and Remediation of Petroleum Hydrocarbon

Contaminated Soils and Sediments. 2 Visual indications may include surface staining, vegetation dieback, sheen or product floating on surface or groundwater. 3 Refer to ASC NEPM Schedule B2 Section 7.5 and EPA Victoria IWRG 702: Soil sampling (June, 2009) for sampling and

characterisation of stockpiles

UNCLASSIFIED

Appendix B – Management and Treatment Options

UNCLASSIFIED

Management options Following the soil characterisation and waste classification of the stockpiled material, there should be enough information to inform the most appropriate management option for the material.

Examples of potential management options for stockpiled materials are presented below, as per the Department of Defence Manual for the Management & Remediation of Petroleum Hydrocarbon Contaminated Soil and Sediments (Department of Defence, 2009).

Separation

Once the different types of soil have been classified according to the nature and concentrations of contaminants present, they should be physically separated so far as reasonably practicable. This ensures that the volume of materials recovered as a potentially valuable resource is maximised and the volume that requires further processing, treatment or disposal is minimised.

The methods used to separate more contaminated material from less contaminated materials vary according to the nature of both the material and the contaminant.

Soil, rock and similar materials can generally be simply excavated and stockpiled in discrete areas according to their classification, however other solid materials may require more complex separation techniques:

• Mixed demolition wastes may require mechanical screening or hand-picking to separate out different material types.

• Where materials are stockpiled, it may be prudent to place the materials on a lined surface to reduce the opportunity for sediment movement or leaching of contaminants to soil or groundwater.

Segregation

Contaminated materials often need to be stored prior to re-use, possibly for only a few hours or perhaps years. During this time it is essential to ensure that the transfer of contaminants between material types and to external receptors (i.e. people and the environment), is kept to a minimum. It may be prudent to place the materials on a lined surface to reduce the opportunity for leaching of contaminants to soil and or groundwater. Similarly, appropriate sediment control measures (e.g. silt mesh) should be implemented.

Stockpiles should be bunded to prevent the runoff of contaminated surface water and sediments and to reduce the opportunity for leaching. Covers should be used on stockpiles to minimise the opportunity for emissions to the atmosphere, surface water runoff and generation and transfer of contaminated dust. The types of materials stored should also be documented within the environmental management system for the site.

Disposal off-site

Depending on the waste characterisation of the stockpiled soil, contaminated material may be disposed of off-site to an appropriately licenced waste disposal facility pre- or post-treatment. If the waste soil requires treatment, the treatment process may occur on-site or off-site at an appropriately licensed premises, pending approvals or other requirements by state authorities.

Management ex situ (storage)

Contaminated soil may be excavated from the stockpile and contained in a dedicated long-term or short-term storage area. This may be on or off-site in a manner consistent with local regulatory requirements. Short-term storage options may be considered if, a) the soil treatment technology selected is unsuccessful, or b) immediate funding to treat the soil is not initially available. Having the available space and resources to ensure waste segregation is achieved is

UNCLASSIFIED

an important consideration when evaluating this endpoint. For example, on site containment cells may be considered as a possible management option. If containment of contaminants on site is deemed to be an option, then the following key considerations would need to be made regarding the containment cell design/specification:

Site specific conditions (depth and quality of groundwater, permeability of underlying lithology/geology)

Physical/chemical properties of the waste

Containment cell siting, design and construction

Re-use of soil/sediment on-site

This re-use of stockpiled material assumes that the soil can be treated to a quality that is suitable for re-use in accordance with Defence and state and territory regulatory requirements. Stockpiled soil should be assessed for its suitability to be re-used onsite or elsewhere based on an assessment against human health and ecological criteria (e.g. NEPM) and leachability. If treatment of contaminated soil is required, it may occur on-site or off-site at an appropriately licensed premise.

Management in-situ

The management of impacted stockpiled soil without extensive excavation may be undertaken to remove the contaminants. This form of management may be achieved via:

a) Installation of a containment wall.

b) Use of in-situ remedial techniques such as bio-venting.

c) If a risk assessment finds the environmental and human health risks are acceptable.

Management of residual impacted stockpiled soil may need to be approved by an Environmental (Contaminated Land) Auditor and may require a site-specific management plan.

Treatment options To reduce contamination concentrations in stockpiled soil to levels that are suitable for re-use, or off-site disposal, treatment technologies may need to be considered. Potential treatment options for stockpiled soil may include biopiling, landfarming, soil washing, solidification stabilisation, incineration and thermal desorption.

Selection of the most appropriate treatment technology is based on a number of site-specific factors including:

• Chemical and physical characteristics of the soil.

• Degree of technical difficulty, reliability, cost and time associated with the treatment technology.

• Operational and long-term management requirements.

• Site location and availability of equipment and resources.

A matrix of treatment technologies, against CoPC, is provided in the US Federal Remediation Technologies Roundtable (FRTR) https://frtr.gov/matrix2/section3/table3_2.pdf.

Further information on soil remediation and treatment options are provided in the following Defence reference guides:

• Manual for Management and Remediation of Petroleum Hydrocarbon Contamination Soil and Sediments, July 2009 (provided as a supplementary annex of the DCMM)

• Guidelines for Consideration of Sustainability in Remediation of Contaminated Sites, December 2010 (provided as a supplementary annex A of the DCMM)

UNCLASSIFIED

Appendix C – Soil Stockpile Risks and Mitigation Measures

Information contained in Table C-1 is based on the South Australia EPA (2020) Guideline for stockpile management: Waste and waste derived products for recycling

UNCLASSIFIED

Table C-1 Soil Stockpile Risks and Mitigation Measures

Soil Stockpiles: Risks and associated mitigation measures

Risks Potential impacts Examples of factors affecting the risks and resulting impacts

Suggested measures

Pollution of surface water and groundwater via leaching or runoff of contaminants and particulates

• Reduced natural resource quality and potential use

• Site contamination (land, surface water and ground water)

• Site degradation • Reduced ecosystem quality and

function

• Soil type and chemical composition (including leachability)

• Climate • Effectiveness of management

procedures and practices • Engineering controls • Topography and proximity to

watercourses

• Containment of leachate and diversion and control of stormwater

• Bunding • Low permeability surface • Cover/enclosure • Stormwater runoff controls such as silt traps and

settlement ponds • Management plans • Suitable site selection and separation distances

Dust emissions • Adverse impact on amenity • Damage to property • Human health impacts (e.g.

respiratory problems)

• Climatic conditions including exposure to winds

• Elevation • Stockpile size • Waste type • Exposed soils/unsealed roads

• Physical controls (e.g. sprays, covers, compaction, screening, enclosure, windbreaks, binders and road surfacing)

• Traffic (control frequency and speed) • Minimised stockpile height • Suitable site selection and separation distances • Materials handling, operational procedures and

management, e.g. moisture content during handling or cessation of activities in adverse conditions

Odour emissions • Adverse impacts on amenity • Human health impacts (e.g.

respiratory problems) if odours are related to vapour

• Soil type and chemical composition • Climatic conditions • Management procedures • Land use and compatibility with

surrounding land use

• Physical controls (e.g. containment, cover, enclosure, vapour filtration)

• Suitable site selection and separations distances • Effective management and monitoring procedures • Maintain aerobic conditions

Adverse visual amenity • Interference with the enjoyment of the area and creation of unsightly or offensive conditions

• Stockpile size • Waste type • Land use and compatibility with

surrounding land use

• Minimise stockpile size • Suitable site selection and separation • Physical controls (e.g. screening, enclosure)

UNCLASSIFIED

Soil Stockpiles: Risks and associated mitigation measures

Risks Potential impacts Examples of factors affecting the risks and resulting impacts

Suggested measures

Stockpile instability • Stockpile collapse, leading to potential injury and damage to infrastructure

• Waste type

• Topography

• Climatic conditions

• Stockpile height

• Materials management

• Implement appropriate materials handling procedures

• Minimise stockpile size

Inadequate platform stability and suitability

• Site contamination • Infiltration of leachate into and

damage to underlying groundwater aquifers

• Damage to stockpiled area and infrastructure

• Potential damage to capping material if storage is on old landfill, leading to increased risk of emissions from leachate and gas generation

• Ground instability

• Waste type • Sub-surface geology and structure

below sub-base • Sub-base material characteristics

(particle size, Atterberg limits, density)

• Likelihood of sub-base failure e.g. due to faulting, sliding, slumping, caving or climatic impacts

• Proximity to extraneous sources of ground vibrations including railway lines

• Suitability designed and engineering facility • Minimise stockpiling size and overloading • Suitable size selection and separation distances

Excessive accumulation of material

• Adverse impact on amenity • Increased risk of dust emission and

other resulting impacts • Expanding capacity of site

• Ineffective or lack of planning and management procedures

• Speculative stockpiling • Lack of materials balance and flow

management • Acceptance of inappropriate

materials

• Pre-planning and consideration in the design arrangement and construction techniques to eliminate and/or reduce generation of excess material requiring stockpiling

• Appropriate materials flow calculations, management and procedures

• Site Management Plans

Note: Based on the South Australia EPA (2020) Guideline for stockpile management: Waste and waste derived products for recycling