LNAPL Extraction Trial Update

Transpacific Industries Group Ltd Tullamarine Closed Landfill

Tonight’s Presentation

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Scope of Work.

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LNAPL recovery system design.

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Extraction trial methodology.

LNAPL Leachate Well Locations Approximate Former Quarry Extent

Trial Objectives

• • • • The overall objectives of the extraction trial were to: Identify the most appropriate extraction option for LNAPL recovery; Derive design parameters; Improve the prediction and understanding of the potential LNAPL yield; Projected system implementation timelines and likely efficiency, if feasible.

Baildown Test Objectives

• Baildown tests are to better understand the LNAPL behaviour: • How in well LNAPL thickness varies and how it recovers after pumping.

• LNAPL Transmissivity (T) - a key metric to assess recoverability.

• measure of how much liquid can be transmitted • “potential seepage rate (per unit area)” • computed by measuring rate of LNAPL seepage to well after pumping.

Baildown Test Objectives

• • T metric is used in US, Europe as well as Australia.

In addition to T, other key metrics include: • Ability to pump LNAPL from the waste • comparison of initial in-well volume and volume pumped. • Ability to sustain LNAPL pumping rates.

Baildown Tests

• On all leachate extraction wells.

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Well selection determined by internationally accepted guidance (ASTM E2856 – 11, 2012. Standard Guide of

Estimation of LNAPL Transmissivity).

• Initial LNAPL thickness (>30cm) • Well integrity testing using dummy pumps

Baildown Tests

• Involves removal of at least 80% of the initial in well LNAPL thickness utilising a pump.

• Monitoring of fluid levels, after pumping. • The rate the LNAPL seeps back allows T to be computed.

• Results of the baildown tests determine longer term extraction trial feasibility at each location.

Stage 1 Baildown Testing

Enclosed Well Head Assembly Sealed Area Cap Vapour Flared Tank (1 m 3 ) GACs 2x Leachate Well Leachate Well Perforations LNAPL thicker in well LNAPL Leachate Pump (intake positioned in LNAPL)

Outcomes

• • Baildown tests: 15 th May through to 16 th July 2014.

Tests completed on all wells that met international guidance standards (13 of the 14 wells).

• • • 1 well not tested (L6) - insufficient LNAPL present to undertake trials (<30 cm).

Tests completed without incident - no vapour or liquid losses.

LNAPL safely transported and destroyed by waste receiver.

Outcomes

• Best yielding well (L1) showed a very slow recovery rate (>1 month).

• However, it was retested to ensure all LNAPL was removed. • The extra test reconfirmed the very low T and very slow recovery rate.

450 350 250 150 50 -50 Initial in-well LNAPL (L) LNAPL Extracted (L) In-well LNAPL Extracted(L) L from waste L1 137 470 105 365 L1 ® 57 482 57 425 L2 137 85 124 -39 L3 92 124 74 50 L4 106 86 95 -9 L5 91 63 63 0 L7 115 135 104 32 L8 161 155 140 15 L9 106 120 75 45 L10 22 19 20 -1 L11 117 71 96 -25 L12 166 150 133 17 L13 112 101 104 -3 L14 51 50 48 2

% of Total LNAPL extracted (L) L12; 7% L11; 3% L10; 1% L13; 5% L14; 2% L9; 6% L8; 7% L7; 6% L1; 45% L5; 3% L4; 4% L3; 6% L2; 4% Total Volume Extracted (L)

Volume from in well storage (L) Volume from waste (L)

Well

L1 L2 L3 L4 L5 L7 L8 L9 L10 L11 L12 L13 L14

LNAPL Extracted (L)

952 85 124 86 63 135 155 120 19 71 150 101 50

Extraction Time (min)

398 62 72 46 110 83 78 117 79 51 130 35 61

2,111

1,237 874

0,08 0,07 0,06 0,05 0,04 0,03

T Calculated vs T metric

T metric – 0.074 m 2 /day 0,02 0,01 0 L1 Early Time L1 Late Time L1 repeat L2 L3 L4* L5* L7 Early Time L7 Late Time L8 L9 L10* L11 L12 L13 L14

Location L1 L1 Retest L2 L3 L4 L5 L7 L8 L9 L10 L11 L12 L13 L14 T Criteria

Trial Results

Extraction from waste

No No No No No No No No No No No No No No Yes (365L) Yes (425L) No Yes (50L) No No Yes (32L) Yes (15L) Yes (45L) No No Yes (17L) No Yes (2L)

Ability to sustain extended pumping rates

No No No No No No No No No No No No No No

Conclusion

• • • • • • • • T metric (potential seepage rate) not met at any location.

Extraction from waste limited to 8 of 13 wells tested indicating very low well capture radius.

LNAPL from remaining wells from well storage only. Of the 8 wells, only L1 yielded appreciable volumes (>50L).

Pumping at best yielding well (L1) sustained for only 398 minutes over 2 events. Repeat testing of L1 confirmed low T and very low recovery rate.

Very slow LNAPL recovery to wells (typically > 1 month). On the basis that no metric was met, progression to longer term trials is not practical or achievable.

Transpacific discussion points

• Trial Report together with Independent Review Panel findings to be made available for review and comment as part of consultation period.

• Stakeholder Consultation period of 6 weeks to commence once above reports are made available.

• Transpacific to continue to progress requirements as set out in the PAN and provide an update at the November Community Meeting.

Questions?

Back up slides

In-well LNAPL thickness fluctuations

LNAPL Exaggeration Mechanisms

Transmissivity

• LNAPL Transmissivity (T): • • • • • measure of ability of formation to transmit LNAPL.

function of fluid, LNAPL saturation/mass and formation. easy to measure.

indicates potential mobility.

Different to transmissivity in traditional groundwater sense • Saturated groundwater conditions • LNAPL presence typically sporadic and not continuous

• • • In-well LNAPL thickness does not provide an indication of recoverability?

In-well thickness: function of the hydrostatic conditions under which the LNAPL it exists.

Water columns in wells are not used indicate potential groundwater yields and equally not appropriate for LNAPL.

Data below from a confidential remediation site in Melbourne

Well ID MW21 MW14 MW12 MW8 MW17 b (m) 2.17

2.83

3.26

0.15

2.21

T (m 2 /min) 4E-06 4E-05 7E-05 1E-04 1E-04 Avg Recovery Rate (L/hr) 15 13 8.5

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