TPI presentation

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Tullamarine
Rehabilitated
Landfill
> 26 November 2014
Post Closure Management Plan Progress
Cap
2010
Mounds 1 & 2 Cap
Construction
2011
2012
2013
Drainage connection approved by
Melb Water & SEWPaC Works
2014
Tender & Works
Commence
2014/15.
Green Arrows = Water Act Vic,
1989 Deliverables
Groundwater & Surfacewater Management (Risk Assessments Completed in
2004 & 2007 and Indicated Low Risks. A technical review was completed in
2011/12 of over 100 boreholes and along creek continues to confirm the same).
Next Review
2014/15
Oil
Groundwater Management Protocol (Approved by SRW)
Liquid Product (LNAPL) Extraction
(Feasibility trial commenced 2014)
Gas
Water
Cap Audit Completed
Landfill Gas Management (Landfill Gas
Sampling and Perimeter Monitoring completed
2013 & final flare design & install 2014)
Grey Arrows = Environmental
Protection Act Vic, 1970,
Deliverables
Deliverables (Anticipated Dates)
>
>
>
>
>
LNAPL Trial Practicability Assessment (March 2015)
Groundwater technical review (March 2015)
Groundwater management plan update (March 2015)
Landfill Gas Audit (September 2015)
Stormwater Connection (Construction to Commence
Summer 2014/15)
> Landfill maintenance (mainly mowing - ongoing)
> Ongoing monitoring (landfill gas, groundwater)
LNAPL Trial Remaining Tasks
> Consultation (workshop & questions tonight)
> Questions are able to be put to EHS (and the IRP) until
end of December (note now end of February 2015 as
discussed in meeting)
> Draft report issued to community mid to late January
> Special meeting with EHS & A. Lane mid February
> Practicability Assessment Report (Issued March 2015)
> The Practicability Assessment Report will include
consultation process and responses to questions from
community.
Reminder - What does the EHS report mean?
> The trial has shown LNAPL extraction is not feasible
because the volumes and recovery rates are so low
> At current levels of recovery extraction will take in the
order of 1,000 years
> The LNAPL is effectively immobile
> Other technologies were ruled out during planning /
design because of risks to cap integrity and/or risk of
mobilising contamination
Reminder - What was proposed?
> The EHS information is indicating further field trials are
not justified
> However it is only fair that the community and
stakeholders have time to consider the detail in the
technical information
Why is it so difficult to extract?
> Biodegradation is occurring in the landfill
> Microbial bugs consume the easier less viscous (thinner
more mobile) compounds first leaving thicker and less
mobile compounds until last
> Biodegradation is happening because :
> The landfill temperature is declining
> The landfill gas production is also occurring (and
declining)
What will happen to the LNAPL?
> It won’t move
> It will eventually turn into an inert material that looks
something like black carbon
> It will undergo anaerobic biodegradation and this will be
explored in the EHS Practicability Assessment report (the
process is called anaerobic reductive degradation and
includes dechlorination, ie, chlorine in PCB is removed)
> Transpacific will continue to monitor
Next Steps
> Opportunity to ask questions and seek clarification.
> Reports were made available on the community web site.
> Consultation continues beyond the original 6 to 8 weeks
envisaged from the 15th Sept (when the community can ask
questions / comment on the reports).
> Opportunity to ask questions at tonight’s meeting.
Next Steps ctd…
> Transpacific to make EHS and the Independent Review
Panel available for questioning (tonight).
> Transpacific will use tonight’s meeting to assist the
community formulate questions to our experts.
> We will take further questions until end of December
(now end of February) and EHS can respond in detail in
the Practicability Assessment report (March 2015).
> Site visit to the Landfill (two members attended)
Reminder of The Technology Screen
• Hydraulic Containment
• Impermeable Barrier
• Excavation and Disposal
• In-Situ Vitrification
• In-Situ Cement Solidification
•Fluids Extraction
• Active Skimming
• Belt Skimming
•Steam Injection
•Resistive Heating
•Solvent Extraction
•Surfactant Flushing
•Air Drive / Water Flood
•Vacuum Extraction
•Vacuum Enhanced Hydraulic
Recovery
• In-Situ Chemical Oxidation
(ISCO)
•Bioremediation
Technology Considerations
Health, safety and environmental impacts/ risks, including:
• Generation of vapour / dust emissions
• Penetrations through and/ or damage to the land fill cap
• Permanent changes in LNAPL characteristics
• LNAPL mobilisation
• Landfill fires
• LNAPL storage and handling
Multiple Technologies Employed at
Tullamarine Landfill
> Cap (Installed)
> Hydraulic Control (Assessments will be completed March
2015 – SRA, HA and LNAPL Trial)
> Gas Collection and Emissions Flaring (Installed and currently
undergoing confirmatory assessment).
> GW & LFG Monitoring (Monitoring network installed and
monitoring is ongoing)
> Natural Attenuation [attenuation assessment completed for the
Technical Review (TRAR), currently being reviewed by
Auditor].
Technology Considerations
> The Natural Attenuation assessment indicates
dissolution from LNAPL (until it naturally depletes) will be
managed effectively via Monitored Natural
Attenuation. More to report on this at the next meeting.
> The landfill gas collection system vacuum can be
considered as an active management measure for
collecting vapour emissions and assisting with stripping
volatile components of the LNAPL which are typically the
most soluble as well.
Mobility Over Time
Data from US
0.4
0.3
Tn
(m2/d)
After R. Charbeneau, 2012
0.2
0.1
0
0
2
4
6
Time (Years)
8
10
Recovery Rate Over Time
Data from US
First liquid
disposal about
1973 & last
disposal in 1987
(about 40 years
since first
disposal & 27
years since last
disposal.
0.4
Extraction Only
Bio degradation Only
Extraction + Bio degradation
0.3
ML
0.2
0.1
After T. Sale, 2012
0
0
10
20
Time (Years)
30
40
Tullamarine Landfill
> The landfill is in the period between ability to practically
extract and LNAPL being absorbed to clay particles
> Note that intervention has potential to cause greater
harm
Biodegradation Processes
Biodegradation Processes - Landfill
Biodegradation Processes - Landfill
Cap
Gas Collection Layer
Flare
Waste
LNAPL
Biological Activity
Biological Activity
Leachate
PCB CONCENTRATION
Max Concentration (mg/kg)
Median Concentration (mg/kg)
250
Concentration halves in anaerobic soil
every 9 years, Beurskens et al. (1993)
200
150
100
Location
PCB Concentration
(mg/kg)
L11
5
L4
21
L5
29
Well 6
31
L7
38
L13
60
L14
102
L3
102
L8
106
L12
123
L1
188
L2
210
Well 15
212
L9
215
50 mg/kg NEPM Soil Guideline for Industrials Sites
50
0
0
20
40
60
80
100
120
Monitored Natural Attenuation
Natural Attenuation and Biodegradation
> Biodegradation via anaerobic reductive dechlorination and
volatilisation enhanced with the landfill gas collection
system. These two process are likely the key ones for the
ultimate degradation of the LNAPL at the site.
> LNAPL at Tullamarine is more complex than “standard
petroleum site”. Biodegradation is also considered important
for a wide range of contaminated sites and as such has much
wider applicability than just standard petroleum sites.
Biodegradation (US EPA Fact Sheet)
Biodegradation (US EPA Fact Sheet)
> “Fortunately, petroleum hydrocarbons appear to degrade
to less harmful products in almost all cases.”
USEPA Remedial Technology Options Fact Sheet ‘Monitored Natural
Attenuation of Petroleum Hydrocarbons’
Disclaimer
This document has been prepared by Transpacific Industries Pty Ltd (ABN 40 010 745 383) (“Transpacific”) for the purposes of
providing the recipient with an update on the status of rehabilitation works at Tullamarine landfill site. This document has been prepared
on the condition that it is for the exclusive information and use of the recipient.
This document may not be reproduced, distributed or published by any person for any purpose. No part of this document may be
quoted or referred to in any other document.
With the exception of information provided by external sources, Transpacific retains all applicable intellectual property rights which arise
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This document is subject to the limitations, assumptions and qualifications referred to in it.
In addition to any other rights available to them, Transpacific or any related party (“Transpacific Parties”) herein expressly advise that
they:
1.
make no representation or warranty, express or implied, as to the accuracy, currency, reliability or completeness of any
statements, estimates, opinions or other information contained in this document; and
2.
to the maximum extent permitted at law, the Transpacific Parties are not responsible or liable in any way whatsoever for any claim,
loss, damage, cost or expense, whether direct, indirect, consequential or otherwise, arising (whether in negligence or otherwise)
out of use or reliance on this document, its contents or any omissions from it.
Transpacific Parties means Transpacific, its related bodies corporate, directors, officers, employees, representatives, consultants and
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Thank you
for your time
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