INFORMATION REGARDING · 2019. 1. 4. · Nearest Neighbours 4. Monitoring Locations – Landfill Gas 5. Monitoring Locations – Ground and Surface Water, Leachate 6. Gas Field Layout

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for

CityofGreaterGeelong

EnvironmentalAuditReport:s.53V–RiskofHarm

(EPARef.CARMSNo.68991‐8)

DRYSDALELANDFILLFoundsRoad,Drysdale

June2016toJuly2018

Revision No.

Summary of Amendments Reviewed by Issued by Issue Date

V1 S Leverton S Jenkins 5 Dec 2018

EnviroRisk Management Pty Ltd ABN 24 069 947 904 PO Box 183 LARA VIC 3212 P: 03 5282 3773 F: 03 5282 4430 www.envirorisk.com.au QUALITY CONTROL Our Ref: AR68991‐8 Version: V1 Date: 5 December 2018

Environmental Audit (s53V): Drysdale Landfill, Founds Road, Drysdale – CoGG

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TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 6 1. INTRODUCTION ............................................................................................................................. 15

1.1 REFERENCES TO REPORT DETAIL .............................................................................................. 15 1.2 SITE & SURROUNDINGS ................................................................................................................ 16

2. OBJECTIVE & SCOPE ....................................................................................................................... 17 3. ACTIVITY AND COMPONENTS ........................................................................................................ 19 4. SEGMENTS OF THE ENVIRONMENT ............................................................................................... 20 5. ELEMENTS OF THE ENVIRONMENT ............................................................................................... 20 6. BENEFICIAL USES .......................................................................................................................... 21 7. AUDIT CRITERIA ............................................................................................................................ 23

7.1 PREVIOUS S.53V AUDITS ..................................................................................................................... 24 8. LANDFILL OPERATIONS ................................................................................................................. 24

8.1 LANDFILL AGE, DESIGN & LIFE EXPECTANCY ....................................................................................... 24 8.2 STAGING: CLOSED, OPERATIONAL & PLANNED CELLS ......................................................................... 25 8.3 LANDFILL GAS MANAGEMENT .............................................................................................................. 26 8.4 LEACHATE MANAGEMENT .................................................................................................................... 28 8.5 STAKEHOLDER ENGAGEMENT ......................................................................................................... 28 8.6 ENVIRONMENTAL PERFORMANCE ........................................................................................................ 28 8.7 CONCEPTUAL SITE MODEL (CSM) ...................................................................................................... 29

9. LANDFILL MONITORING ................................................................................................................ 29 9.1 OVERVIEW OF ENVIRONMENTAL MONITORING PROGRAM (EMP) ....................................................... 29 9.2 INTERPRETATION OF MONITORING RESULTS AGAINST BENEFICIAL USES .............................................. 30 9.3 REPORTED OUTCOME ........................................................................................................................... 31

10. AUDIT OUTCOMES ......................................................................................................................... 32 10.1 NOTIFICATION AND SCOPE CONFIRMATION ........................................................................... 32 10.2 SITE INSPECTION ............................................................................................................................ 32 10.3 LITERATURE ASSESSMENT .......................................................................................................... 33

10.3.1 Environmental Monitoring Program (EMP) ................................................................................ 33 10.3.2 Licence Compliance Monitoring Reports 2016/2017 and 2017/2018 ........................................ 33 10.3.3 Landfill Gas Monitoring Data, Risk Assessment & Remediation Action Plan ............................. 34 10.3.4 Landfill Operations Risk Assessment (LORA) .............................................................................. 34

10.4 STATUS OF PREVIOUS AUDIT RECOMMENDATIONS ............................................................. 36 11. RISK ASSESSMENT ......................................................................................................................... 36

11.1 GROUNDWATER RISK .................................................................................................................... 37 11.1.1 Geology and hydrogeology interpretation ................................................................................. 37 11.1.2 Multi‐criteria risk assessment ..................................................................................................... 37

11.2 LANDFILL GAS RISK APPRAISAL ................................................................................................ 37 11.3 AMENITY RISK ASSESSMENT ...................................................................................................... 42 11.4 REVIEW OF THE CONCEPTUAL SITE MODEL (CSM) ................................................................ 43

12. COMPLIANCE MONITORING APPRAISAL ........................................................................................ 44 12.1 COMPLETENESS OF CURRENT MONITORING REGIME & ITS IMPLEMENTATION ...................................... 44 12.2 INTERPRETATION OF MONITORING RESULTS ......................................................................................... 44 12.3 RE-VERIFICATION OF MONITORING PROGRAM ...................................................................................... 45 12.4 FREQUENCY OF MONITORING PROGRAM AUDIT .................................................................................... 45

13. HYDROGEOLOGICAL ASSESSMENT ................................................................................................ 46 14. CONCLUSIONS ................................................................................................................................ 47

14.1 RECOMMENDATIONS ............................................................................................................................ 50 15. REFERENCES ................................................................................................................................. 53 16. AUDITING NOTES ........................................................................................................................... 55 TABLES 1. Executive Summary ‐ General 2. Executive Summary ‐ Physical 3. Executive Summary ‐ Summary of Recommendations


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4. Location of audit findings within this report. 5. Multi‐criteria risk analysis – Groundwater 6. Landfill gas result summary (2016‐17) 7. Landfill gas result summary (2017‐18) 8. Multi‐criteria risk analysis – Landfill Gas 9. Changes to EMP 10. Table of Recommendations FIGURES 1. Site & Locality 2. Zoning 3. Nearest Neighbours 4. Monitoring Locations – Landfill Gas 5. Monitoring Locations – Ground and Surface Water, Leachate 6. Gas Field Layout APPENDICES 1. Environmental Monitoring Program Verification Protocol 2. Audit Protocols 3. Previous Audit Recommendations 4. EPA Licence (as current at audit commencement i.e. amended 14/12/2017)


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ABBREVIATIONS

ABBREVIATION DESCRIPTION

APS Annual Performance Statement

AS/NZS Australian and New Zealand Standard

BPEM Best Practice Environmental Management

CSM Conceptual Site Model

EMP Environmental Monitoring Program

EPA Environment Protection Authority of Victoria

ERA Environmental Risk Assessment

Ha Hectares

LFG Landfill Gas

LGRAP Landfill Gas Remediation Action Plan

LORA Landfill Operations Risk Assessment

mg/L Milligrams per litre

NEPM National Environment Protection measure

OH&S Occupational Health and Safety

PIW Prescribed Industrial Waste

P&E Act 1987 Planning and Environment Act 1987

PM10 Particles with a size of 10 micron and less

PPE Personal Protection Equipment

s.53V Section 53V of the Environment Protection Act 1970

SEPP State Environment Protection Policy

SOP Standard Operating Procedure

TDS Total Dissolved Solids concentration (in mg/L)


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EXECUTIVESUMMARY Table 1: Summary of Audit Information EPA File reference no. CARMS No. 68991‐8

Auditor Stephen Jenkins AUDITOR TERM OF APPOINTMENT 1 Nov 2014 to 31 October 2019

Name of person requesting audit Mr Jack Taylor

Relationship to premises/location Waste Services Unit, City of Greater Geelong

Date of request 4/05/2018

Date EPA Notified 10/05/2018

Completion date of the audit 5/12/2018

Reason for Audit The City of Greater Geelong is required under Licence Condition LI_L1 to “ …. implement a monitoring program, verified by an environmental Auditor appointed pursuant to the Act, which enables both you and the EPA to determine compliance with this licence.” while EPA Licence condition LI_L2 requires Council to “ …. Engage an environmental auditor appointed pursuant to the Act to conduct the environmental audits at the frequency specified in the verified monitoring program.”

Description of activity to be audited The Drysdale landfill facility having an area of approximately 55 Ha, and being owned and managed by the City of Greater Geelong and operated under EPA Licence 74222.

Current Land Use Zoning Farm zone (FZ)

EPA Region South West

Municipality City of Greater Geelong

Dominant – Lot on Plan Lot 2, PS506107

Additional ‐ Lot on Plan(s) ‐

Site / Premises name Drysdale Landfill

o Building / complex sub‐unit No

n/a

o Street / Lot – Lower No. 502 o Street / Lot – Upper No. 510 o Street Name Founds o Street type (road, court, etc) Road


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o Street suffix (North, South etc)

n/a

o Suburb Drysdale o Postcode 3222

GIS Coordinate of Site centroid1 o Latitude (GDA94) o Longitude (GDA94)

38.169679 S

144.632458 E

Members and categories of support team

John Leonard – Hydrogeological technical expert

Simon Leverton – waste specialist and auditor

Outcome of the Audit Over the 2 year audit period for this statutory audit (specified in section 1.6 of the EMP) CoGG has demonstrated substantial compliance with relevant conditions of EPA Licence 74222. Monitoring obligations have been carried out in general accordance with the monitoring program, which has been regularly reviewed and revised in response to previous audit recommendations. A single complaint was received from the community by CoGG concerning landfill operations (litter). Data recording and reporting obligations were in the main met. Commendably, the capacity to treat collected stormwater stored in the east pond by sediment flocculation prior to release to the environment has now been established. No discharges are reported to have occurred during the audit period. Dust monitoring commenced during the audit period and has produced acceptable results, although verification of units is required. Noise monitoring taken at the nearest sensitive residence, whilst complying with the ‘day period’ trigger level, exceeds the more stringent ‘evening period’ level which applies on Saturday afternoons and Sundays, when the landfill also

1 Longitude and latitude (decimal degrees) co‐ordinates in the 1994 Geocentric Datum of Australia (GDA94) is required to six decimal

places.


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operates. A recommendation to review noise sources at the site and take steps to reduce these has been made as a pre‐emptive management measure to avoid a possible complaint. A number of opportunities for improvement to the monitoring program have been identified during the audit. Recommended improvements are captured in Table 3 below. Landfill operations are considered largely to be effectively managed and there is no imminent risk of significant harm to the environment. A high level of control over risk elements was witnessed during the audit, and good progress has been made in implementing the recommendations made in the previous biennial audit. The following discussion elaborates on the recommended measures to further improve risk management practices and demonstrate compliance.

Water Monitoring data suggests groundwater may be impacted by leachate from the landfill despite the significant depth of the water table below the bottom of the landfill. Background bores need to be maintained free from blockage so that reliable comparisons can be made, and robust conclusions drawn from, the monitoring data. Although a detailed evaluation of hydrogeological conditions has been provided, the auditor notes that interpretation of geological aspects differs between each of the Annual Compliance Reports (Meinhardt & Tonkin & Taylor) and the Hydrogeological Report (LandServ). The potential effects that groundwater sink (quarry) has on influencing groundwater flow is presently not being reflected in the contour mapping. Clarification of some aspects of the hydrogeology, estimation of travel times to the Swan Bay wetland receptor and a


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siting and design parameter review for likely additional down hydraulic gradient bores is warranted.

Amenity (Dust, Noise, Odour, Litter) Dust monitoring recommended in the previous biennial audit, and included in the monitoring plan, has included PM10 monitoring for only the 2017/18 summer period. The dust monitoring charts presented in the Annual Compliance Report 2017/18 adopts a scale of mg/m3 as opposed to µg/m3. This needs rectification to gauge compliance.

No registered complaints were received regarding noise during the Licence period audited. The community however, raised ongoing noise annoyance as an issue, particularly during weekends at times when the wind directly resulted in ‘clearly audible’ conditions.

It is noted that noise measurements taken at the nearest sensitive residence, whilst apparently complying with the ‘day period’ trigger level, may trigger the more stringent ‘evening period’ level which applies on Saturday afternoons and Sundays, when the landfill also operates. Additionally, monitoring reports prepared do not comment relating to the application of penalty adjustments (e.g. tonality) although tonal reverse beepers were recorded during monitoring. Compliance with NIRV therefore needs re‐evaluated at the nearest noise sensitive receptors to the north, south and east. Pro‐active noise reduction measures should be investigated and implemented, particularly targeting this more sensitive period of the week. Daily inspections are not being completed. The LORA review specifically includes reference to the need for these to continue. The details covered in the daily inspections would benefit from being re‐visited to confirm their continued relevance.


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There have not been no complaints of odour emanating from the site during the audit period.

Litter was noted at and beyond the site boundary. Community concern has been raised about ongoing off‐site litter presence. Whilst clean‐up is progressed quickly, site controls did not strictly meet EPA guidelines for screen height management of litter. Vigilance is required on windy days to better control litter within site boundaries including activation of an extreme weather policy that includes very high winds. Commendably a smaller tip face appears to be routinely maintained compared with that noted during previous audits.

Fire Preparedness Further work is required in aligning and clarifying procedures relating to hot spot extinguishing, and ensuring that all relevant personnel are appropriately trained and training is kept current.

Landfill Gas. Landfill gas monitoring over the audit period has identified exceedances of trigger levels related to CO2. These have in part been attributed to the nature of the lithology of the area (limestone yielding CO2 under acidic conditions), and to naturally occurring soil organic carbon content. They are nonetheless also consistent with generation of gases from deposited waste, particularly emanating from the unlined cell (Stage 1). These exceedances have been rated as posing a low risk.

Hazardous Materials Storage Correct storage of oils and some recyclable wastes (lead‐acid batteries) is needed.

Land/landscape. A rehabilitation plan has now been developed and progressive rehabilitation will occur with completion of the trial phytocap now underway.


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The rehabilitation plan development should proceed in full consultation with the Drysdale community consultation group.

The Auditor confirms that a biennial audit frequency is appropriate conditional on implementation of improvement recommendations in a timely manner.

Further Works or Requirements Recommendations for improvement and priorities for action are captured in a table within the audit report (attached below).

TABLE 2: Physical site information

Historic Land Use Farming Current Land Use Farming Zone ‐ FZ Surrounding Land Use – north Farming Zone ‐ FZ Surrounding Land Use – south Farming Zone ‐ FZ Surrounding Land Use – east Farming Zone ‐ FZ Surrounding Land Use – west Farming Zone ‐ FZ Proposed land use zoning ‐ Nearest surface water receptor ‐ name Frederick Mason Creek Nearest surface water receptor – direction East Groundwater Segment C

SIGNED:

Stephen John Jenkins dated5December2018 ENVIRONMENTAL AUDITOR (APPOINTED PURSUANT TO THE ENVIRONMENT PROTECTION ACT 1970)


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Table 3: Summary of Recommendations

No. Recommendation Relevant Objective

Priority

AR’18‐1 Install appropriately sized bund for minor quantities of chemicals (particularly drums of oil) stored in shed at transfer station.

EPA Licence Ll_G1BPEM 788.3

B

AR’18‐2 Direct the attention of all relevant personnel to the Licence requirement that EPA is to be notified of all Licence non‐compliances immediately (or within 24h if not practicable immediately), as is clearly stated in both the Operations Manual and the EMP.

EPA Licence Ll_G2BPEM 1322.9

A

AR’18‐3 Noise is to be measured at (or in reasonable proximity to) the nearest sensitive receptors to the north, south and east on Saturday pm or Sunday, and compared with applicable ‘evening period’ NIRV limit (i.e. 41 dB(A)) including reference to any applicable penalty adjustments as per SEPP N‐1 (assessment procedures called up in NIRV).

EPA Licence LI_A2

B

AR’18‐4 Review operational practices with a view to developing measures to reduce the level of noise impacting on the nearest sensitive locations.

BPEM 788.3 B

AR’18‐5 Undertake refresher training in waste acceptance procedures for all relevant personnel. EPA Licence LI_WA1

A

AR’18‐6 Maintain the current program of litter removal from the boundary and beyond, and finalise and strictly implement the new procedure for inclement weather management.

EPA Licence LI_WM3

C

AR’18‐7 Complete the modification of litter screens at the tipping face so they are all 4m in height. EPA Licence LI_WM3.1 BPEM 788.3

A

AR’18‐8 Revise the EMP to: 1. ensure that the specified times for conducting monitoring accord with those being followed by the relevant sub‐contractors, as recommended by their experts; 2. add in an additional parameter for total suspended particulate (TSP) nuisance dust monitored initially by visual assessment of dust observed to be transporting beyond the site boundary; 3. Report PM10 results and chart in µg/m3. 4. change Table 5 ‘Time’ column for noise criteria to reflect Saturday afternoon and Sunday action levels equivalent to the evening period criteria. 5. Include the turbidity surface water discharge criteria specified in EPA Pub. 788.3, together

EPA Licence LI_L1

BPEM 788.3

A


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with internally‐used limits for post‐flocculated stormwater, in Appendix C (as a separate table). 6. conduct daily site inspections of water discharge as referenced in the recent LORA report (Landserv, 2018c).

AR’18‐9 Have a specialist update the hydrogeological assessment so that it definitely maps the distribution of potentially impacted aquifers (eg Quaternary Sediments, Older Volcanics, Werribee Formation, Fyansford Formation) using all available data and information. The specialist hydrogeologist that undertakes this update should have expertise in subsurface geological mapping (basin analysis), including stratigraphic interpretation and log correlation as well as hydrogeology, and be commissioned following consultation with the Drysdale Community Group. Specifically the updated hydrogeological assessment needs to: ‐ provide an illustrative map of the various aquifers and groundwater flow systems; ‐ include the influence of the quarry pit on groundwater flows clearly illustrated on a contour diagram; ‐ provide estimated travel times for groundwater to reach Swan Bay; and ‐ outline the need for, design detail and location of, additional down hydraulic gradient bore(s) so as to evaluate down gradient water quality of bores currently exhibiting leachate impact (e.g. MW15), and potentially such bores as MB9A and MW 22 (if indicators continue to reveal a high risk of leachate presence i.e. via ratio analysis).

EPA Licence LI_DL1.3

B

AR’18‐10 Ensure that leachate is extracted from cells 6A and 6B whenever the leachate level is recorded to be above 300mm.

EPA Licence LI_L4.1

B

AR’18‐11 Amend the Operations Manual to include procedures for extinguishing hotspots discovered at the tip face, and when EPA is to be notified of a hotspot. Amend other emergency response procedures to align with this and cross‐reference as required.

EPA Licence LI_L15

A

AR’18‐12 Review and amend the draft Fire Response procedure so that it clearly sets out a series of step‐wise actions to respond to fire, in addition to assigning role/responsibilities to positions.

EPA Licence LI_L15

B

AR’18‐13 Review the adequacy of fire prevention and response training for landfill operations personnel, and consider whether this should be established for all relevant personnel as a separate specialist training session.

EPA Licence LI_L15

B


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AR’18‐14 Ensure that where activities are undertaken that are subject to the requirements of a Licence condition, such as provision of intermediate cover, documented evidence is collected to verify that the Condition was complied with.

EPA Licence LI_L24

C

AR’18‐15 Batteries being kept for off‐site recycle should be stored in a way that prevents any leakage of acid onto land or into surface waters.

EPA Licence LI_DL1.2

A

AR’18‐16 Waste oil being taken off‐site by a contractor for recycle elsewhere must be accompanied by an EPA Waste Transport Certificate. Procedures for consigning prescribed wastes from the site must be detailed in the Operations Manual.

EPA Licence LI_DL1.2, Ll_G4 BPEM 788.3

A

AR’18‐17 Finalise the new draft procedure relating to inclement weather and cross‐reference within the Operations Manual under s.8.2.2 Extreme Weather Events.

BPEM 788.3 A

AR’18‐18 Prepare reports for works undertaken under s.30A Approvals and submit to EPA as required. s.30A Approvals A AR’18‐19 Conduct a review of the landfill operations risk assessment annually as required by EPA

guidelines. EPA Pub. 1323.3 C

AR’18‐20 Have ‘an expert in the field’ review potential biological transportation risk to Swan Bay from transition of birds between the landfill and the Ramsar wetlands.

BPEM 788.3 B

AR’18‐21 Annually calculate VOC combustion efficiency and maximum VOC emissions from the on‐site flare.

BPEM 788.3 A

AR’18‐22 Ensure that independent consultant annual environmental monitoring compliance reports: i. reference the correct EPA Licence version in force at that time; ii. comment on compliance with all monitoring obligations, including odour monitoring compliance, to fulfil annual performance statement requirements; and ii. make a concerted effort to monitor all groundwater bores specified in the EMP, or recommend measures to quickly replace, repair and/or re‐sample same where not possible.

Other B

AR’18‐23 Obtain input from the Drysdale community consultation group during preparation of the rehabilitation plan.

Other B

%A = HIGH. Attend to over short term (


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1. INTRODUCTION

Stephen Jenkins of EnviroRisk Management Pty Ltd (the Auditor) was engaged by the City of Greater Geelong (CoGG) to undertake this “environmental risk of harm” audit (s.53V Audit) conducted under Section 53V of the Environment Protection Act, 1970 (the Act).

The audit was commissioned in response to action conditions of EPA Licence # 74222 (relevant amendment for audit December, 2017 (refer Appendix 4); namely:

‐ LI_L1 You must implement a monitoring program, verified by an environmental auditor appointed pursuant to the Act that enables both you and the EPA to determine compliance with this licence.

‐ LI_L2 You must engage an environmental auditor to conduct the environmental audits at the frequency specified in the verified monitoring program.

In addition, Condition Ll_L4.3 of the Licence states:

By 30 June 2018 you must provide to EPA a hydrogeological assessment for the premises that: a) is in accordance with Hydrogeological Assessment (Groundwater Quality) Guidelines (EPA Publication 668, released September 2006); b) specifies the maximum leachate management level for all unlined and partially lined cells which protects beneficial uses of groundwater and allows for the effective management of landfill gas; and c) is verified by a person who has been appointed as an environmental auditor under the Environment Protection Act 1970.

This audit includes the verification of the Hydrogeological Assessment prepared for CoGG by consultants Landserv Pty Limited (Landserv).

The period of the audit is from 1st July, 2016 through to 30th June, 2018 inclusive, representing a two year (biennial) time period since the previous s.53V audit in 2016.

1.1 REFERENCES TO REPORT DETAIL

EPA publication 1323.3 Landfill Licensing Guidelines (EPA Victoria, 2016) specifies the requisite scope and content requirements of the audit. To assist with identification of the precise location(s) of report content the following table is provided.

Table 4: Location of audit findings within this report.

Audit Findings Location in Audit Report Risk of landfill operations to beneficial uses identified by the environmental auditor

Section 6: Beneficial Uses

Section 11: Risk Assessment

Comment on the risk assessments (site operation and landfill gas) prepared by landfill operator

Section 10.3.4 Landfill Operations Risk Assessment (LORA)

Section 11: Risk Assessment

Appendix 2: Audit Protocol (Section LI_L5 Auditor Finding &


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Comments, EPA Licence 74222)

Appendix 2: Audit Protocol (Sections ‘Hydro‐geological assessments, Groundwater, Air quality, Auditor Finding & Comments, BPEM (publication 788.3))

Comment on the completeness of the environmental monitoring program, including comment on the audit frequency

Section 12 Compliance Monitoring Appraisal

Appendix 1: Environmental Monitoring Program Verification Protocol

Assessment of the adequacy of the monitoring program to determine compliance with licence conditions

Section 10.3.1 Environmental Monitoring Program

Section 12.3 Re‐verification of monitoring program

Appendix 1: Environmental Monitoring Program Verification Protocol

Appendix 2: Audit Protocol (EPA Licence 74222)

Assessment of implementation of the monitoring program

Section 12.1 Completeness of the current monitoring regime and its implementation

Interpretation of monitoring results Section 12.2 Interpretation of monitoring results

Appendix 2: Audit Protocol (Section ‘Monitoring Risk based program, Auditor Finding & Comments, Licence Assessment Guidelines’

Verification of the environmental monitoring program

Section 12.3 Re‐verification of the monitoring program

Verification of the Hydrogeological Assessment report

Section 13 Hydrogeological Assessment

Implementation of progressive rehabilitation Section 12.1 Completeness of the current monitoring regime and its implementation

Appendix 2: Audit Protocol (EPA Licence 74222)

Recommendations Section 14.1: Recommendations

Implementation of recommendations made in previous audit reports

Section 10.4 Status of previous audit recommendations

Appendix 3: Previous Audit Recommendations

Adequacy of Conceptual Site Model Section 11.1.1 Geology and hydrogeology interpretation

Section 11.4 Review of Conceptual Site Model

1.2 SITE & SURROUNDINGS

The site, known on title as Lot 2, PS506107, is 55 hectares in size, and is located at 502‐510 Founds Road, Drysdale (Figures 1 & 2). The site is located in a Farm zoning in the Local Planning Scheme Zoning Map (Figure 2) and is surrounded on all sides by Farm‐zoned land.

Neighbouring land use includes:

North Farmland used for grazing north of Founds Road, with farm buildings and rural houses approximately 200m from the landfill boundary.

East Farmland used for grazing. A rural house is present approximately 900m


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from the landfill boundary.

South Farmland used for grazing. A rural house is approximately 400m for the south east corner of the landfill.

West Immediately west of Becks Road is a commercial bin storage yard, farmland for the southern half of the western boundary, and a private quarry for the northern half. Large sheds associated with the quarry are approximately 200m from the landfill boundary.

Beyond the quarry is farmland used for grazing and beyond Founds Road, horticulture (blueberries). Houses are located to the west with the nearest, associated with the farm, at a distance of approximately 500m from the landfill boundary.

Nearest neighbours are shown in the aerial photograph in Figure 3.

The topography of the area is undulating with the central aspect of the landfill falling within a stormwater drainage channel. The drainage flows from central west to a low point central east. The catchment prior to the landfill extends some 1.5 kilometres west and drains into the ephemeral Frederick Masons Creek, immediately east of the landfill boundary.

Frederick Masons Creek forms part of the Swan Bay catchment. Swan Bay is situated 5 kilometres south‐east of the site and is a Ramsar Convention‐listed wetland2.

The geology of the area is described in detail within the Hydrogeological Assessment Report (Landserv, 2018a) and elsewhere. In general, the landfill is based on ‘silty clay and basaltic clay with various sized fragments of weathered basalt,’ but is recognised to be located on an upthrown structure, the Bellarine High, that exhibits differing stratigraphic units resulting in a complex setting of aquifers and groundwater flow systems.

2. OBJECTIVE&SCOPE

CoGG is required under Licence Condition LI_L1 to:

“ …. implement a monitoring program, verified by an environmental Auditor appointed pursuant to the Act, which enables both you and the EPA to determine compliance with this licence” ; and under Licence condition LI_L2 to: “ …. Engage an environmental auditor appointed pursuant to the Act to conduct the environmental audits at the frequency specified in the verified monitoring program.”

2 The Convention on Wetlands, called the Ramsar Convention, is an intergovernmental treaty (of which Australia is a signatory) that provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources.


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The scope of the audit is to fulfil the above Licence condition requirements, as well as those as specified in Condition Ll_L4.3 as referred to in the Introduction. This has been achieved via a process of documentation review and interrogation, inspections and interviews.

The audit was progressed in stages, namely:

1. Notification preliminaries: EPA was advised of the audit commencement and outline of the risk of harm scope (in accordance with EPA guidelines) on 10th May, 2018.

2. Identification & evaluation of reports & data: The undertaking of a desk top/literature‐based assessment, coupled with a site and surrounds review, to obtain sufficient lines of evidence to understand the context of the site, the significant aspects warranting evaluation and an assessment of the level of risk of harm. The desk top/ literature assessment included record and data identification and also discussions with Council as to:

previous audit and reports prepared on and surrounding the site; progress in implementing the recommendations of the previous independent

audit conducted by EnviroRisk (EnviroRisk, 2016); compliance outcome reports prepared over the audit period; the adequacy of the Conceptual Site Model (CSM) including soil structure,

local geology, topography, hydro‐geology and land‐use; the latest monitoring schedule; monitoring conducted at the landfill and results, including quality control and

assurance measures, to fulfil compliance against EPA Licence (including landfill gas, groundwater, surface water, air, land/ landscape and noise);

whether neighbour complaints and Authority notices occurred and, if so, what issues were reported and mitigation actions taken;

an assessment of whether the monitoring and other management activities undertaken by CoGG and its contractors included consideration of the relevant guidance material such as: the Landfill Best Practice Environment Management Guidelines, Landfill Licensing Guidelines and others;

a review and verification of the Hydrogeological Assessment conducted for the landfill (as required in Condition Ll_L4.3);

a review of minutes of the meetings of the community consultation group, and direct communications, including a meeting, with representatives of the Drysdale Community Group.

3. Audit protocol construction: Development of an audit protocol and risk assessment platform to ensure all aspects of the audit criteria were canvassed and evaluated according to a systematic auditing (in general accordance with AS/NZS ISO19011:2014 Guidelines for auditing management systems) and a risk assessment process; (via semi‐quantitative risk assessment


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techniques of reasonably foreseeable environmental hazards associated with landfill operations).

4. Site inspection: A site inspection was conducted on 25th July, 2018 at the landfill, and a follow‐up meeting with CoGG personnel occurred on 15th August at CoGG’s waste management offices at Anakie Road, Lovely Banks.

5. Interviews: Interviews were held with CoGG staff and contractors engaged in environmental monitoring and reporting.

6. Stakeholder engagement: Consultation was conducted with CoGG managerial personnel, contractors, and landfill operational staff relating to amenity considerations. A selection of residents neighboring the landfill were interviewed.

7. Interrogation of testing, surveys and analytical results: Conduct a desk top review of documents, testing and analytical reports of an appropriate sample size, to form an opinion as to the extent, quality and veracity of results and reports.

8. Additional investigation & data requirements: Conduct follow‐up on additional items that arose during preceding stages of the audit.

9. Evaluation of risk of harm including recommending means to bridge information gaps and/or mitigate risk of harm: Run through hypothetical scenarios with the audit team to establish whether risk controls appear adequate or warrant improvement. Form an opinion and document that opinion on the environmental risk of harm presented at the site using semi‐ quantitative risk assessment methods.

10. Reporting: Prepare an audit report in plain English with clear recommendations for action to improve monitoring and/or controls to ensure the environmental quality of the local environment is protected.

3. ACTIVITYANDCOMPONENTS

The activity audited is the operation of the Drysdale landfill which is located at 502‐510 Founds Road, Drysdale and has a physical size of 55Ha. Figure 1 shows the site and its locality.

The audit considered all aspects of landfill operation with particular consideration of the CSM, the risk assessment process, the Environmental Monitoring Program (EMP) and results associated with same, the management and progressive rehabilitation of landfill cells, and operational performance as assessed by the regulator’s inspections.


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The boundaries of the audit (i.e. premises location) are those specified in the EPA Licence. An illustration of the physical boundary of the audit is shown in Figure 1 – Site & Locality. The audit has noted any influence outside the audit boundaries that may be relevant. No actual confirmatory sampling of waters, air or noise was conducted by the Auditor during the course of the audit.

The on‐site phase of the audit took place during July 2018, involving inspections of the site and surroundings, and in particular the landfill, the adjoining quarry, Founds Road, Becks Road, Murradoc Road and Portarlington‐Queenscliff Road.

Activities and components specifically not within the audit scope included: ‐ the rationale for the original siting; ‐ occupational noise and air aspects; ‐ off‐site traffic impacts and visual amenity presented by the landfill; ‐ risk to the public who may temporarily access the site to drop off waste and recyclables; ‐ the broader risk associated with climate change aspects; ‐ new cell technical specifications and the construction QA plan and cell construction audit.

4. SEGMENTSOFTHEENVIRONMENT

The Act defines a segment of the environment as any portion or portions of the environment expressed in terms of volume, space, area, quantity, quality, or time or any combination thereof. The segments of the environment relevant to the scope of this audit are:

i. the area of land where the landfill is located; ii. groundwater beneath the site; iii. the atmosphere including landfill gases at and surrounding the site; iv. surface water on the site; v. the environment surrounding the landfill to which the activity may pose a risk.

5. ELEMENTSOFTHEENVIRONMENT

The Act defines an element of the environment as any of the principal constituent parts of the environment including waters, atmosphere, land, vegetation, climate, sound, odour, aesthetics, fish and wildlife. The following environmental elements are relevant within the audit boundaries:

i. Land (as it relates to landfill gas, contaminant or leachate migration); ii. Water (including surface waters at potential on‐site discharge points and beyond

the landfill site and groundwater); iii. Air (landfill gas hazard and discharge risk to on‐site and surrounding beneficial

use); iv. Amenity issues (including noise (off site), litter, vermin, vectors, dust and odour) ;

and


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v. Human health and well‐being, as well as flora and fauna health.

6. BENEFICIALUSES

“Beneficial use” is defined in the Act as being a use of the environment or any element or segment of the environment which:

i. is conducive to public benefit, welfare, safety, health or aesthetic enjoyment and which requires protection from the effects of waste discharges, emissions or deposits or the emission of noise; and

ii. is declared in a State Environment Protection Policy (SEPP) to be a beneficial use.

Beneficial uses for the land uses surrounding the site are drawn from SEPP (Air Quality Management), SEPP (Waters of Victoria), SEPP (Groundwaters of Victoria) and SEPP (Prevention and Management of Contamination of Land).

The following beneficial uses are specified as warranting protection:

SEPP (Air Quality Management) ‐ a) life, health and well‐being of humans; b) life, health and well‐being of other forms of life, including the protection of ecosystems

and biodiversity; c) local amenity and aesthetic enjoyment; d) visibility; e) the useful life and aesthetic appearance of buildings, structures, property and materials;

and f) climate systems that are consistent with human development, the life, health and well‐

being of humans, and the protection of ecosystems and biodiversity.

SEPP (Waters of Victoria) ‐ Beneficial uses of surface water are drawn from Table 1 of SEPP (Waters of Victoria). The relevant segment is the General segment for Frederick Masons Creek as defined within Schedule F6 Catchments of Port Phillip Bay. This lists the beneficial uses as ‘slightly to moderately modified’ ecosystems with water quality suitable for: ‐ Primary contact recreation, secondary contact recreation, aesthetic enjoyment,

indigenous cultural and spiritual values, non ‐ indigenous cultural and spiritual values, agriculture and irrigation, aquaculture, industrial and commercial use, human consumption after appropriate treatment and fish, crustacean & molluscs for human consumption.

Note: Given the ephemeral nature of the creek and the general cleared hills land use in the area, the beneficial uses that are in italics are unlikely to be realized.


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Ultimately creek waters discharge to Swan Bay, approximately 5km to the south‐east. Swan Bay is designated as an aquatic reserve segment within Schedule F6 of the SEPP3. The beneficial uses of Swan Bay include “natural ecosystems”, which requires that quality parameters for all indicators must not vary from background levels. With appropriate stormwater management, including the containment of all waters up to a 1 in 20 year storm event, standard operations represent a low risk of influencing the beneficial uses of Swan Bay.

The Cleared Hills & Coastal Plains beneficial uses are therefore considered applicable to the upper range of Frederick Mason Creek to guide this audit. Downstream, Swan Bay is considered to be a “natural ecosystem” at which background levels apply.

Water quality criteria used to assess whether beneficial uses are being protected are drawn from the modified systems criteria specified in the ANZECC Australian Water Quality Guidelines for Fresh and Marine Waters, 2000.

SEPP (Groundwaters of Victoria) ‐

Beneficial uses of groundwater are determined based on the “salinity” of the water (as measured by the concentration of total dissolved solids, or TDS). The TDS of groundwater beneath the site is generally within the range 3,501‐13,000 mg/L, making it a Segment C quality groundwater in accordance with Table 1 of the SEPP. However, TDS does fluctuate between the groundwater monitoring bores on site, with MB17 (the up‐gradient background bore) having a TDS of approximately 3,000 mg/L, indicating a Segment B quality groundwater aquifer. Based on regional aquifer information and the fluctuating salinity across the site a Segment C category is considered appropriate for beneficial use determination at and surrounding the landfill.

Relevant beneficial uses of Segment ‘C’ groundwater are:

a) Maintenance of ecosystems; b) Agriculture, parks and gardens; c) Stock watering; d) Industrial water use; e) Primary contact recreation; f) Buildings and structures

SEPP (Prevention and Management of Contamination of Land) ‐

a) maintenance of modified and highly modified ecosystems; b) human health; c) buildings and structures; d) aesthetics; and e) production of food, flora and fibre.

3 Swan Bay is managed by Parks Victoria under the Port Phillip Heads Marine National Park Management Plan, July 2006, established under the National Parks Act, 1975.


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Of the above‐listed beneficial uses, the following are considered to not be relevant in the context of this audit, and for the reasons stated:

climate systems, and the protection of ecosystems and biodiversity – only the direct operational impacts of the landfill on or near the site are considered in the audit scope, not the more global impacts on climate and biodiversity.

7. AUDITCRITERIA

Audit criteria are the policies, procedures or requirements used as a reference against which the audit evidence has been compared. The principal criteria that are applicable for this audit include:

Current EPA Licence # 74222 last amended on 12th September 2018, relating to Drysdale (Premises No. 72476)

Environmental Monitoring Program (EMP), CoGG (last revised 29 June 2018)

Environment Protection Act 1970, and supporting policies, specifically ‐

o Waste Management Policy (Siting, design and management of landfills) o State Environment Protection Policy (Groundwaters of Victoria) o State Environment Protection Policy (Waters of Victoria) o State Environment Protection Policy (Prevention and Management of

Contamination of Land)

o State Environment Protection Policy (Air Quality Management) Relevant published guidelines and Standards including:

o EPA Victoria (2007) Publication 953.2 Environmental Auditor Guidelines for Conducting Environmental Audits.

o EPA Victoria (2015) Publication 1147.2 Environmental Auditor Guidelines – Provision of Environmental Audit Reports, Certificates and Statements.

o EPA Victoria (2015) Publication 952.5 Environmental Auditor Guidelines for Preparation of Environmental Audit Reports on Risk to the Environment.

o EPA Victoria (2009) Publication 1270 Assessment of the potential for methane gas movement from Victorian landfills.

o EPA Victoria (2015) Publication 788.3 Siting, design, operation and rehabilitation if Landfills (Best Practice Environmental Management Series).

o EPA Victoria (2006) Publication 668 Hydrogeological Assessment (Groundwater Quality) Guidelines.

o EPA Victoria (2011) Publication 1321.2 Landfill Assessment Guidelines


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o EPA Victoria (2017) Publication 1322.9 Licence Management Guidelines o EPA Victoria (2016) Publication 1323.2 Landfill Licensing Guidelines o EPA Victoria (2011) Publication 1411, Noise from Industry in Regional Victoria o EPA Victoria (2012) Publication 1479 Landfill gas fact sheet o EPA Victoria (2012) Publication 1490 Closed Landfill Guidelines

AS/NZS ISO 31000:2009 Risk Management – Principles and Guidelines

AS/NZS ISO19011:2014 Guidelines for auditing management systems National Environment Protection (Assessment of Site Contamination) Measure 1999 as

amended (the NEPM). Other relevant legislation, regulation and guidelines, as well as supporting documents for the EMP, are provided in the references to this report.

7.1 PREVIOUS S.53V AUDITS

Six (6) previous Section 53V environmental risk of harm audits have been completed since 2010:

1. EPA REF. CARMs 59646‐4 dated October 2009; Luke Cattlin, Noel Arnold and Associates

2. EPA Ref. CARMs 67140‐1 dated April 2010; Luke Cattlin, Noel Arnold & Associates 3. EPA Ref. 68991‐1 dated June 2011, Wayne Drew, Tonkin and Taylor Pty Ltd 4. EPA Ref. 67140‐2 dated 10 December 2012, Anthony Kortegast, Tonkin and Taylor

Pty Ltd This report referenced all previous Audit recommendations and stated that “any residual issues are addressed as part of this report”.

5. EPA Ref. 68991‐2 dated 9 September, 2014, Stephen Jenkins, EnviroRisk Management Pty Ltd.

6. EPA Ref. 68991‐5 dated 19 August, 2016, Stephen Jenkins, EnviroRisk Management Pty Ltd.

This Audit report therefore draws from, and builds on, the most recent s.53V Audit report issued in August 2016. All previous recommendations that were deemed to be ‘open’ are captured within that year’s report recommendations.

8. LANDFILLOPERATIONS

8.1 LANDFILL AGE, DESIGN & LIFE EXPECTANCY

Landfilling of waste at the Drysdale site is believed to have commenced in 1982, and has therefore been occurring there for the last 36 years. The original landfill design was reported to be a trench and cover disposal process (referred to as Stage 1, in the northern part of the site – Figure 4). Stage 1 of the landfill’s operation had minimal environmental design controls; there was no engineered liner and detailed records are not available on all


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types of waste disposed. A review of average waste volumes received over the period 1983 – 2002 reveals approximately 862,000 tonnes of predominantly municipal type waste was landfilled. Based on this quantity, and combined with the area covered by Stage 1 (i.e. 115,000 m2) and pit excavation techniques, the landfill base is considered to be well above the regional water table height i.e. filling occurred to a maximum depth of around 18m and the water table is approximately 40m below surface level (Landserv, 2018a). Stage 1 has been capped with approximately 1m of clay and is presently grass covered.

Stage 2 was designed with leachate control and a compacted clay base. Stage 2 has been filled to capacity and has a temporary cover prior to it being rehabilitated. Stage 2 waste has been placed in a cell with a reported maximum level of 15m below ground level and the water table is at a depth of 20‐25m below ground level (CSM, Landserv, 2018a).

Stage 44 (filling was completed in 2015) represents best practice landfill design and comprised a membrane and designed clay liner system and a small operational face with adequate cover material immediately stored adjacent to landfilling activities. The liner system was subjected to a separate environmental audit before filling commenced. Both Stage 2 and Stage 4 have leachate collection systems.

Stage 6 commenced construction in 2016 and is currently the active part of the landfill.

Stage 5 is under construction and almost complete and, as with Stage 4, has a membrane and clay lined based and sides and was separately audited by an EPA‐appointed Auditor prior to commencement of landfilling. Further details of the landfill staging program are provided in the table below.

The hydrogeological assessment report indicates the total tonnage received from 1983 to 2017 is 2,278,000 tonnes (Landserv, 2018a). The same reference confirms that tonnages accepted have ranged from 31,000 to 103,000 tonnes per annum, with an average of 67,000 tonnes between 1982 and 2017, with an increase expected to a future peak of 131,000 tonnes/annum. Waste types are reported to comprise:

‐ 64.7% municipal solid waste ‐ 32.7% commercial and industrial waste; and ‐ 2.6% construction and demolition.

Life expectancy at planned acceptance rates will be for another 8 years, until around 2026.

8.2 STAGING: CLOSED, OPERATIONAL & PLANNED CELLS

Landfill waste disposal has progressed over Stages as described below:

Stage Cells Description

1 N/A Commenced 1983. Closed 2002. Capped by 2003 Unlined with no leachate extraction system

4 Reportedly there has not been a Stage 3, it became part of Stage 2.


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Landfill gas extraction system directs captured methane to a flare for combustion. 13x gas wells are installed catering for closed landfill. There is no energy recovery.

2 1,2,3 Commenced 2003. Filled by 2009. Final capping planned to be complete 2017, but has not yet commenced.

Landfill gas extraction system directed to flare. 22x gas collection wells installed.

There is no energy recovery. However, this is being reviewed.

Stage 3 was amalgamated into Stage 2.

There is therefore no Stage 3.

4 Part 2, 4

Received inert waste.

Eastern section crosses abuts cell 4.

Received inert waste on the Stage 2 side of the cell clay liner.

4 4, 4A Received inert, putrescible and PIW (animal effluent and residues, filter cake).

Annual tonnage was approximately 80,000 t/yr. (PIW component 229 tonnes/year)

Cell 4 is now filled and covered. Cell 4a has not yet been completely filled. There is still a wedge of fillable volume between Cell 4a and Cell 5 that will gradually be filled over the next 8 years.

Final capping has not yet commenced.

6 6A, 6B Cells have been constructed and landfilling is progressing in 6B.

5 5A, 5B Future cells with a landfill life expectancy until 2026. Tonnage to peak at 133,000 t/yr. 5A lining is being constructed at the time of audit.

8.3 LANDFILL GAS MANAGEMENT

The landfill gas extraction system layout is shown in the concept design drawing prepared by LMS energy (Appendix B of Landserv, 2018b, reproduced below as Figure 6). The system includes approximately 64 wells across Stages 1, 2 and 4 of the landfill. CoGG advises that LMS currently manages landfill gas extraction and flaring under contract to CoGG.

Collected methane is currently continuously combusted in an on‐site flaring facility. We are advised that CoGG, through LMS, plans to commission a landfill gas renewable energy facility later in the year, thereby utilising extracted landfill gas for beneficial use rather than flaring it off.

The risk presented by landfill gas is discussed in a number of documents including the revised Landfill Operational Risk Assessment (Landserv, 2018c), the revised Landfill Gas Risk


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Assessment (Landserv, 2018b) and the revised Landfill Gas Remediation Action Plan (Landserv, 2018d). All these reports have been reviewed since the previous biennial audit in 2016 (EnviroRisk, 2016).

The Landfill Gas Risk Assessment (Landserv, 2018b) reviewed the LFG risk based on the results of the most recent monitoring (i.e. both 2015/16 and 2016/17), and taking into account relevant recommendations made by the auditor in 2016. The LFGRA also re‐estimated the methane mass balance for the landfill based on modelling methods adopted under the NGER scheme, which indicated that the gas extraction system removed approximately 70% of methane generated over the course of the years 1 July 2015 to 30 June 2017. The current extraction rate is 450m3/h, which is considered to represent an efficiency of approximately 63%.

In summary, following adoption of the Auditor’s recommendation (EnviroRisk, 2016) that the risk matrix in EPA Publication 1321.2 be used to rate identified risks rather than that contained in the EPA NSW guidelines (EPA NSW, 2012), the overall risk profile is now rated more highly, and is summarised in the review report (Landserv, 2018b) as follows:

A high risk applies to off‐site residents/buildings associated with the lateral migration of landfill gas resulting in asphyxiation and/or explosion. Rigorous application of the current control measures should result in an acceptable residual risk.

A high risk also applies to maintenance/excavation workers who may undertake work in trenches adjacent to filled areas either on or off‐site (i.e. not above filled areas). Rigorous application of the current control measures should result in an acceptable residual risk.

A high risk applies to on‐site workers (including maintenance, excavation workers and gas technicians) and buildings (if and when relevant) associated with the vertical migration of landfill gas through capped areas resulting in asphyxiation and/or explosion in trenches or in buildings. This applies to future onsite buildings as it is understood no buildings are currently constructed upon filled areas that have been capped. Rigorous application of the current control measures should result in an acceptable residual risk.

A medium risk applies to on‐site and off‐site vegetation associated with both lateral and vertical migration of landfill gas through the cap and death of vegetation.

A low risk applies to the potential for elevated oxygen to cause an internal landfill fire. The proposed commercial operation of a generation station and the prevention of oxygen ingress are mutually beneficial goals.

A low risk applies to excessive emissions from the landfill gas flare reducing local air quality.


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8.4 LEACHATE MANAGEMENT

Leachate generated from the northern unlined Stage 1 section of the landfill is not currently monitored or collected.

Leachate from Stages 2 (cells 1 and 3), 4 (cells 2, 4, 4A) and 6 (cells 6A & 6B) is being collected on the cell liners and is pump‐transferred into the leachate dam in the south‐west corner of the site (Figure 4; dam capacity 4,875 m3). The leachate dam allows water to evaporate, with excess leachate currently being carted for off‐site disposal to sewer by a licensed waste contractor. Leachate depth in the leachate sump riser emanating from each cell is checked on a fortnightly basis, and leachate is removed by pumping when the measured height exceeds a level calculated to be equivalent to 300mm above the lowest point of the cell drainage layer (as required by the Licence).

At the time of writing this report CoGG advises that the pipeline connecting the leachate dam to Barwon Water’s sewer is still under construction. Leachate monitoring results (Tonkin & Taylor, 2018) indicate some exceedances of Barwon Water’s expected Trade Waste permit acceptance criteria, which may require pre‐treatment prior to sewer discharge once the sewer line is connected.

8.5 STAKEHOLDER ENGAGEMENT

The Drysdale Landfill Community Consultation Group (DLCCG) has been operating since June, 2016. It meets for approximately 2 hours in the evening, at a location in Drysdale, every 3 months and comprises members from the local community (numbers vary), as well as representatives from CoGG (4) and EPA (2). The group is convened by an independent professional facilitator.

As a component of the audit, reviews were made of recent community consultation meeting minutes (and response to minutes). As an additional source of information, a meeting was held during late October 2018 with representatives of the consultation group whereby issues that were considered a priority by the community group were relayed to the Auditor and information subsequently provided.

8.6 ENVIRONMENTAL PERFORMANCE

Environmental performance is measured primarily against EPA Licence conditions. A licence compliance report is prepared each year summarising the outcomes of monitoring and responses to previously identified issues raised during the statutory audit process.

The main management system that captures environmental performance is documented within the (draft) Operations Manual (CoGG, 2018b, formerly part of the site’s Environment Improvement Plan, EIP). The risk‐based Environmental Monitoring Program (CoGG, 2018a) details the environmental monitoring that is carried out.


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The Operations Manual needs to be finalised and issued. A number of suggested amendments to that document and the EMP are recommended in this audit report.

8.7 CONCEPTUAL SITE MODEL (CSM)

A conceptual site model (CSM) is described as “a representation of site‐related information regarding contamination sources, receptors and exposure pathways between those sources and receptors. The development of a CSM is an essential part of all site assessments and provides the framework for identifying how the site became contaminated and how potential receptors may be exposed to contamination either in the present or the future.” (NEPM, 1999).

A conceptual hydrogeological model (CHM) can be thought of as a component, or sub‐set, of a CSM, and is a description and depiction of a site “that represents the hydrogeological setting, the movement of groundwater and contaminants, and the interactions between groundwater and the surface”. It also “identifies potential receptors (groundwater users or environments where groundwater discharges).” (EPA Pub. 668, 2006). EPA’s guidelines require that a site hydrogeological assessment includes the development of a CHM.

Following recommendations made in EnviroRisk’s biennial audit report (EnviroRisk, 2014), the CSM was reviewed and updated (Landserv, 2015). The model was primarily prepared to describe and characterise pathways and receptors associated with both landfill gas and groundwater aspects. It discussed the site setting, history, construction, drainage, geology, hydrogeology and potential receptors. The development of the model has been systematic and has reportedly involved many stakeholders. It is a comprehensive appraisal of risk, and is a live document that can be updated as additional information or results dictate.

The CSM was included in the Landfill Operations Risk Assessment review report (Landserv, 2018c), with minor changes made to reflect the landfill gas emissions modelled in the previous year, and other minor changes. The CSM has also been included in the most recent review report of Landfill Gas Risk Assessment (Landserv, 2018b).

9. LANDFILLMONITORING

9.1 OVERVIEW OF ENVIRONMENTAL MONITORING PROGRAM (EMP)

The current environmental monitoring program, as set out in the EMP document (CoGG, 2018a, comprises a comprehensive assessment of landfill environmental quality data and includes landfill gas emissions, surface water, groundwater, leachate, noise emissions, litter and boundary odour surveillance.

Management components of the EMP are documented in table form within the appendices to the document and include a monitoring plan, monitoring methodologies, the analytes to be tested for and the trigger levels/limits against which results are compared, inspection checklists (daily and fortnightly) and site plans identifying monitoring locations.


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9.2 INTERPRETATION OF MONITORING RESULTS AGAINST BENEFICIAL USES

Interpretation of results is provided within the annual Licence Compliance Reports (Meinhardt, 2017, & Tonkin & Taylor, 2018). Each of these reports compiles all data obtained throughout the year (July‐June), summarises outcomes, provides time series graphs of results, tabulates results and includes quality control information. The nature and frequency of the monitoring activities is informed by the outcomes of a comprehensive environmental risk assessment, which is reviewed at least annually, and documented in the Landfill Operations Risk Assessment report (Landserv, 2018c).

The Auditor sampled a number of monitoring reports by “drilling down” to, or interrogating, the underlying raw data and analytical methodologies used. Discussion of specifics is provided in the completed audit protocol appended to this report; particularly the checklist addressing BPEM conformance.

In summary, monitoring was found to be undertaken according to the EMP schedules, and conducted in accordance with specified procedures and relevant guidelines. QC procedures were implemented and QC data reported. The following is noted:

Only fortnightly checks have been occurring at the landfill site over the audit period – the daily checks specified in the LORA and EMP have been discontinued.

A number of groundwater monitoring bores were reported to be blocked or otherwise damaged (MB6, MB7, MW16) in 2017. In the 2018 report, MB08 and MW19 were reported to be blocked or damaged. These bores need to be repaired or replaced;

In 2017, minor leachate impacts were concluded to have occurred at bores MB8, MB9A, MW15, MW18, MW19, MW20, MW21 and MW22 (Meinhardt, 2017);

In 2018, leachate impacts on groundwater deduced from multiple lines of evidence were identified in the vicinity of monitoring bore MW15 (south eastern corner of landfill). Potential leachate impacts (inferred from indirect evidence such as ionic characteristics) were identified at bores MB3A, MB7, MB9A, MW12, MW14, MW16 and MW22 (Tonkin & Taylor, 2018);

Superseded water guidelines (ANZECC, 1992) continue to be referenced in the annual compliance reports as well as in the EMP – these need to be deleted and current guidelines referenced as applicable;

Landfill gas monitoring bore GB5 was blocked in 2017, however no bore was reported as blocked or damaged in the 2018 report;

In 2017 landfill gas monitoring indicated no exceedances of the action level for methane. Some LFG monitoring bores showed exceedances of the carbon dioxide action level, however the levels were reported to be within historical range;


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In 2018 perimeter landfill gas monitoring indicated no landfill gas flows across the site boundary and that methane concentrations, when detected, were negligible (i.e.


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10. AUDITOUTCOMES

10.1 NOTIFICATION AND SCOPE CONFIRMATION

EPA was notified of the audit on 10th May 2018 along with notification of the scope of the audit.

10.2 SITE INSPECTION

The site was visited by the auditor team on 25th July, 2018. During the site inspection in July the following observations were made relating to potential beneficial use impact:

The landfill site was well organised, with public kept away from the landfill disposal area;

Noticeable dirt was tracked onto the southbound lane of Becks Road however it extended north beyond the landfill entrance (suggesting another source such as the Earth Solutions Clean Fill group);

The public area was generally tidy and well controlled; Appropriate signage was present informing of the public drop off and

weighbridge areas; Low odour was detected during the inspection near the face. Landfill compaction equipment was operational and stockpiles of cover material

readily present; CoGG advised that EPA‐approved tarpaulin covers were being deployed at the

end of each day (photo 13); No odour was detected at the boundaries of the landfill; Litter was observed being removed from the boundary fence (south eastern

corner), beyond the fence and from the neighbouring property by teams of contracted personnel (photos 9 & 10);

Cell 6A was being filled; the tipping face was observed to be approximately 30x30m (see Figure 4, and photos 1 & 14 for scale);

Some birds were noted at the tipping area, but much less so than for the previous biennial audit;

Leachate sumps were observed with extraction pipes traversing to the leachate pond;

No discharge of stormwater was occurring from the pond on the eastern boundary (East Pond) – the flocculation plant was observed, and is ready to be operated if necessary;

Litter screens were noted at the tipping area to be both 2m and 4m in height, as the conversion to 4m screens was still underway;

The fuel and oil storage area within the tractor shed in the south west corner of the site was found to not have a containment lip or bund around its floor


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perimeter. 205L drums (approximately 4) stored in this area were therefore not properly bunded;

Lead acid batteries were noted to be stored at the transfer station in a way that could lead to lead‐contaminated hydrochloric acid leaking onto the ground and being washed into the site’s stormwater system. Whilst unlikely to have off‐site impacts, the issue represented sub‐optimal management practice for this waste;

The operation of the weighbridge and waste load checking was observed.

10.3 LITERATURE ASSESSMENT

The audit involved a review of the main supporting information associated with the monitoring program. An overview of the Auditor’s considerations that assisted with the verification process is provided within this section.

10.3.1 Environmental Monitoring Program (EMP)

The EMP (CoGG 2018a) was reviewed and revised a number of times during the audit period, both as a consequence of recommendations made in the previous biennial audit (EnviroRisk, 2016) and to reflect minor changes to the details within the document. As noted in the audit protocol attached below (Appendix 3), a number of our recommendations have not yet been implemented. This have been carried over into our recommendations arising from this current audit.

This 2018 audit confirms the EMP to be a substantive document that, when fully implemented, largely addresses the landfill’s compliance monitoring needs. Following our systematic review of risk coupled with monitoring documentation, some further minor changes and additions have been identified to better enable compliance to be determined.

Recommendations to improve the EMP are included in Section 12.3. Their determination is detailed in Appendix 1, the protocol used to audit the EMP against the minimum requirements

Documents

INFORMATION REGARDING · 2019. 1. 4. · Nearest Neighbours 4. Monitoring Locations – Landfill Gas 5. Monitoring Locations – Ground and Surface Water, Leachate 6. Gas Field Layout