STAGE 4 PROGRESS REPORT

Coastal Acid Sulfate Soils Program (CASSP) 30th October 2002

Demonstrating amelioration of Acid Sulfate Soils, Barker Inlet

Gillman area, South Australia.

Profile BG lsd 1. Actual Acid Sulfate Soil (grey sand & brown mangrove peat covered by light gray clay and soil) containing yellow jarosite mottles (pH <2.5)

Lime (Penrice Grits) being added to the Lime Slot. The drain to the left contains water with a pH < 3

Leaching experiment soil heaps containing sulfidic material that is currently oxidizing to form actual Acid Sulfate Soil. The sulfidic material was excavated from the Lime Slot and drain

STAGE 4 PROGRESS REPORT

Coastal Acid Sulfate Soils Program (CASSP) Milestone Report: 30th October 2002

1. Project title: Demonstrating amelioration of Acid Sulfate Soils, Barker Inlet

Gillman area, South Australia. 2. Contact Details:

Project Manager: Ms Verity Sanders (Port Adelaide Enfield Council). Phone: (08) 8405-6727 Email: vsanders@portenf.sa.gov.au Postal Address: PO Box 110

Port Adelaide SA 5015 Research officer: Dr Rob Fitzpatrick (CSIRO Land & Water).

Project Officer: Mr Brett Thomas (PhD student at The University of Adelaide).

Project Steering committee: The Barker Inlet and Port Estuary Committee (BIPEC) – Contact / secretary Harry Pitrans.

Project Consortium: Port Adelaide Enfield Council, CSIRO Land & Water, Land Management Corporation, Penrice Soda Products, Department of Environment and Heritage, Salisbury Council, Torrens Catchment Water Management Board, Northern Adelaide & Barossa Catchment Water Management Board and the St Kilda Mangrove Trail & Interpretative Centre.

3. Key Dates Project Duration: 1st January 2001 to 31st December 2002. Final report is due 28th February 2002. Stage 4 Progress Report due: 30th October 2002. 4. Project Activities Stage 4 of the project started on 01/05/2002 and finished on 30/09/2002. The agreed activities and milestones are shown below:

Activities Milestones Progress 4.1 Complete ASS rehabilitation trials

as agreed in the stage 2 workshop Rehabilitation trials completed Milestone Met

4.2 Collate monitoring program data Monitoring program findings collated

Milestone Met

4.3 Finalise report detailing conclusions and recommendations from trials

Report finalised Milestone Met Partially

Progress Report for Stage Report against key milestones and performance indicators, including a statement of costs to be lodged with the Department within 30 days of completion of Stage 4. Due date 30/10/2002

A report against each milestone follows.

2

Report against Milestones Activity 4.1 Complete ASS rehabilitation trials as agreed at the Stage 2 workshop. Milestone 4.1 Rehabilitation trials completed. Report: Milestone 4.1. Met

Gillman ASS Remediation Trials The most effective and appropriate techniques (agreed at the Stage 2 Workshop) to ameliorate and manage Acid Sulfate Soils in the Barker Inlet have been completed at the Gillman trial site.

o Re-flooding trials utilizing existing freshwater, tidal and saline ponds in constructed wetlands and brackish water in a storm-water ponding basin (figures 1 and 2).

o Bioremediation trial to re-establish reducing conditions to stop pyrite oxidation by the addition of sulfate-reducing bacteria and various organic wastes, in effect re-establishing the sulfide formation processes that operate in the mangrove soils outside the bund wall (figures 3 and 6).

o Slotting trial using soda lime products to treat acidic discharging meteoric water or groundwater leachate (figures 3 and 5).

o Leaching Experiment using meteoric water or groundwater to flush acidity and contaminants from the soil and treat contained leachates (figure 3 and 4).

o Tidal flushing/drainage trial in highly reducing, eutrophic potential ASS where mangrove dieback is occurring at St Kilda.

We have decided to continue these experiments for the remainder of our Lease Agreement (Appendix 4), which is due to expire on the 30th June 2003.

Figure 1. Saline groundwater pumped bythe windmill is used in the Leachingexperiments. Iron oxide precipitates formbecause groundwater discharges in theRange wetlands. Pond in foregroundreceives treated discharge waters fromthe remediation experiments.

Figure 2. Seawater enters the lowerBarker Inlet Wetlands through tidalgates. This flooded area was formallya salt evaporation pan.

3

Experiments

SumppH=7.5

Bio-reactorpH=7.8

Drain SpoilLeaching,Chemicalneutralisation,Aging,FloodingExperiments

Bioremediation, Lime Slotting, Leaching and Chemical Neutralisation Experiment Plans

SumppH=3.0

20m0m

Weir

Lime slot

N

Green-waste

Monitoring SiteMonitoring Equipment(redox, water samplers)

Drain

Data Logger(Bunker)

Drain

Windmill – Saline Groundwater Pipeline

pH = 7.8 Drain

Pipe

Monitoring Site

Storage site

Drain

Saline G

roundwate

r Pon

d

pH=7.8

Drain

water pH = 2.8

SumppH=7.8

Actual ASSSandy Foreshore sands

Potential ASS(Lagoon Facies shelly clays)

ASS/ PASS (pH3.0)

ASS/ PASS (pH3.0)

ASS(pH3.5)

ASS (pH3.5)

PASS/ shell (pH 7.5)

Experiments

SumppH=7.5

Bio-reactorpH=7.8

Drain SpoilLeaching,Chemicalneutralisation,Aging,FloodingExperiments

Bioremediation, Lime Slotting, Leaching and Chemical Neutralisation Experiment Plans

SumppH=3.0

20m0m

Weir

Lime slot

N

Green-waste

Monitoring SiteMonitoring Equipment(redox, water samplers)

Drain

Data Logger(Bunker)

Drain

Windmill – Saline Groundwater Pipeline

pH = 7.8 Drain

Pipe

Monitoring Site

Storage site

Drain

Saline G

roundwate

r Pon

d

pH=7.8

Drain

water pH = 2.8

SumppH=7.8

Actual ASSSandy Foreshore sands

Potential ASS(Lagoon Facies shelly clays)

ASS/ PASS (pH3.0)

ASS/ PASS (pH3.0)

ASS(pH3.5)

ASS (pH3.5)

PASS/ shell (pH 7.5)

Figure 3. Plan of theGillman remediationexperiment layout.The dominant soilsinfluencing nearsurface ground waterpH are indicated inred (Actual ASSwith pH <3) andgray (carbonatebearing PASS withpH >7).

Bay 1 Bay 2 Bay 3 Bay 4 Bay 5Bay 1 Bay 2 Bay 3 Bay 4 Bay 5

Final holding/ treating pond

Bio-reactor pond

Leachate holding/ treating pond

Lime slot holding

pond

Range wetlands (last pond)

Acidic water from leaching bays

Acidic water from lime slot drain

Neutral waterNeutral water

Neutral water

Neutral water drains to evaporation basin and Barker Inlet

N

Gillman ASS Remediation ExperimentsPonds and water flow

Final holding/ treating pond

Bio-reactor pond

Leachate holding/ treating pond

Lime slot holding

pond

Range wetlands (last pond)

Acidic water from leaching bays

Acidic water from lime slot drain

Neutral waterNeutral water

Neutral water

Neutral water drains to evaporation basin and Barker Inlet

N

Gillman ASS Remediation ExperimentsPonds and water flow

Figure 5. Lime (Penrice Grits)being added to the Lime Slot.Water in the drain to the left has apH of <3.

Figure 6. Photo of the Bio-remediationreactor pond showing water flowdirections.

Figure 4. Leaching experiment soil pilescontained by black plastic bunds. Bays 1& 2 (left) contain oxidized ASS, Bay 3(center) contains carbonate enriched PASSand Bays 4 & 5 contain sulfidic materialand sulfuric horizon material

4

St Kilda PASS Remediation Trial Seawater Flushing Mangrove deaths and samphire habitat loss at St Kilda have been attributed to eutrophication due to nutrient loading causing extreme reducing conditions and/or local subsidence and sedimentation. To test these hypotheses, we developed an integrated monitoring and sampling program and installed automated redox measuring system – Pt electrodes inserted at various depths within 4 different soil environments (Figure 7). The planned field and laboratory characterisation and analyses are essentially complete although it is expected that a few more confirmatory analyses will be required. Redox monitoring will continue for the duration of the Project.

Figure 7. This picture shows redox(Eh) data being downloaded to acomputer from the data logger atsite BSK1 (pristine mangrovewoodland) at St Kilda. The solarpowered data logger is housed inthe canopy of mangrove trees in awaterproof container well above thehigh tide mark.

Activity 4.2 Collate Monitoring Program data. Milestone 4.2 Monitoring Program findings collated. Report: Milestone 4.2 met The collection of soil and water redox conditions at St Kilda (for 5 months) and Gillman (for nearly 2 months) has been very successful. The redox (Eh) data was collected using 16 channel data loggers connected to platinum electrodes placed at different depths within a soil or water profile. New Pt electrodes were designed, constructed, tested and calibrated. These new electrodes are being used by scientists in Queensland Department of Natural Resources and Mines to monitor redox in a range of acid sulfate soils. Temperature and tidal data was also collected. Three data loggers were used to measure 4 contrasting soil profiles at St Kilda: “pristine” mangroves, a samphire covered carbonate sand ridge, degraded mangroves and a eutrophic tidal stream.

5

A 4th data logger was installed to the north of Gillman to monitor the soil/ water redox conditions on either side of the bund wall (as a control to monitor undisturbed mangrove soils and drained mangrove soils). Two data loggers have been installed at Gillman: One to monitor water/ sediment redox conditions within the Bio-reactor, and the other to monitor the wetlands as part of the re-flooding experiments. Over the duration of the remediation trial experiments we have collected several hundred soil and water samples from both St Kilda and Gillman. Sixty samples to date from St Kilda and 150 samples from Gillman have been analysed. Information gathered is being stored on a computer database. It is intended that this information be summarised for incorporation in the final report and be future web based reports.

Soil samples were prepared and archived according to the diagram below.

B u lk S a m p le P r e p a r a t io n & S to r a g e

1 . B U L K , W E T S O IL S A M P L E .

2 . F re e z e 4 0 0 g ( s to r e a n d u s e fo r p y r i te a n a ly s is ) .

3 . 5 0 % K e e p a s w h o le , u n - s ie v e d s a m p le . S to r e .

5 0 % S p li t - d r y a t 4 0 * C fo r m in e ra lo g ic a l a n d c h e m ic a l a n a ly s is

4 . 5 0 % S ie v e - u se < 2 m m a ll n y lo n

5 . < 2 m m F r a c tio n – a s sa y : o D e sc r ib e o C h e m . a n a ly s is o T o ta l c a rb o n o T o ta l s u lfu r o M a g n e tic s u s . o P h y s ic a l . o P a r t ic le s iz e o T i/Z n f ra c tio n s

6 . > 2 m m F ra c tio n : o D e s c r ib e o S to re

7 . P o w d e r – a n a ly s is o X R D o X R F o I C P

G r in d in s e e d m ill

M a y re q u ire c ru s h in g

5 0 % S p lit – d ry a t 8 0 -8 5 * C fo r A S S a n a ly s is

3 . 5 0 % K e e p a s w h o le , u n -s ie v e d s a m p le . S to re .

4 . 5 0 % S ie v e – u se < 2 m m a ll n y lo n

8 . A S S A n a ly s is o T o ta l A c tu a l A c id i ty o P O C A S o T o ta l O x id isa b le S u l fu r o T o ta l P o te n tia l A c id i ty

The planned laboratory analyses and characterisation is essentially complete, however further sampling will be undertaken to confirm analyses and better evaluate ongoing changes within remediation experiments (e.g. pyrite identification using electron microscopy). Further monitoring and sampling will also give us a better understanding of the spatial distribution of contaminants (e.g. heavy metals, arsenic and oxyhydroxysulfates) and respective soil chemical processes required to finalise management strategies for ASS in the Barker Inlet. Some results and conclusions are presented in Milestone report 4.3 below and the presentation slides in Appendix 1 (Communications).

6

Activity 4.3 Finalise report detailing conclusions and recommendations from trials Milestone 4.3 Report finalised. Report: Milestone 4.3 Partially Met A Draft Report detailing conclusions and recommendations from the trials has been written and will be finalised when more analytical data becomes available. Some important analysis from samples had not yet been returned/ reported by the lab (as of the writing date of this report). It is expected that these results will be obtained within the next few weeks and will enable us to finalise conclusions and recommendations for Activity 4.3 and Milestone 4.3. The report will cover: (i) identifying and mapping ASS, (ii) guidelines for sampling and monitoring, (iii) remediation options and appropriate management plans, (iv) remediation methods, (v) evaluation of remediation trials (vi) conclusions and (vii) future work. The following outcomes are briefly summarised below: Gillman Remediation Trials Soil mapping and chemical analyses have indicated significant amounts of actual ASS and potential ASS (PASS) materials exist in areas that are likely to be disturbed by development such as roads, gas pipelines and drains. All of which are planned for the area in the near future. Some soils contain significant acid neutralising capacity (calcium carbonate) that will assist with management of sulfidic materials, but a large portion of the site contains actual ASS with very little carbonate material. It is important to increase awareness of the presence and spatial distribution of both ASS and PASS and their varying degrees of reactivity (e.g. figure 8).

A soils risk map (draft) has been created to indicate the areas of Gillman where these types of soils are likely to be encountered (Figure 8). A conceptual model has also been created to illustrate the chemical and physical changers that occur and are occurring within the Gillman site (figure 9).

Legend Red: ASS (hotter shades are more reactive – more sulfide and/ or less carbonate material) Orange: Mono-sulfide occurrence Black-hashed: PASS with a high neutralizing capacity (carbonate) Light Grey: dredged spoil area Line A-B: approximates the Lime Slot drain. Scale: ~3km across

Figure 8. Gillman ASS Risk Map

A B

7

ProcessesGillman Conceptual model

Changes in Soil Acidity, Carbon and Dissolved ions

UndrainedMangroveWetland

(tidal)

POTENTIALAcid Sulfate

Soil (pH > 7.5)Soil Solution

(mg/L)Fe = <0.01Zn=<0.01As=<0.01Al=<0.1

20% C

0.7msubsidence

GreenhouseemissionsSamphire

Salt marsh(intertidal)

Salt bushSaltmarsh

(supratidal)

ACTUALAcid SulfateSoil (pH<3.5)

DischargeWaters (mg/L)

Fe=2.85Zn=0.86

As=0.014Al=0.1

Bund Wall

(drained 1935)

Acid Sulfate Soil (pH<3.5)

Magazine Creek (pH=7.6)

BarkerInlet

Flood gate

5% C

PLANVIEW

Sea water

Evaporativedischarge

> than recharge

Site discharge toMagazine Creekand Barker Inlet(Minimal)

BundWall

SoilSolution(mg/L)Fe=250

Zn=0.596As=0.134

Al=23

Acid &colloid

production

Figure 9. Diagram illustrating changes that occur when tidal influences are excluded

from mangrove sediments and oxidise. Conceptual models similar to this are being developed to show the physical and chemical changes that are occurring in each of the remediation experiments.

St Kilda Remediation Experiments Seawater Flushing In response to environmental concerns surrounding eutrophication, mangrove deaths and samphire habitat loss in the mangrove woodlands at St Kilda, we developed an integrated monitoring and sampling program to test the following hypotheses:

1. Mangrove deaths are due to nutrient loading and eutrophication. 2. Mangrove death areas are a natural occurrence of sedimentation resulting

from known local subsidence. 3. Samphire habitat loss on carbonate sand ridges is due to local subsidence and

mangrove encroachment. A schematic diagram has been produced to help illustrate the processes that are occurring at St Kilda, figure 10 below. A pamphlet has also been completed to explain the environmental problems associated with nutrient loading in the marine ecosystem. This pamphlet is being distributed through the Mangrove Interpretive Centre at St Kilda and is aimed at late primary schools and high school students. We have also disseminated information though the media; Channel Ten’s “Totally Wild” children’s science program. The pamphlet is contained in Appendix 1 of this report.

8

Mangrove Tree

Data logger

Mangrovepneumatophores(high ground)

Eh = -600mVEh = -120 to – 200mV

Eh probesTidal creek filled/ blockedby rotting organic matter

Mangrove Tree

Data logger

Mangrovepneumatophores(high ground)

Eh = -600mVEh = -120 to – 200mV

Eh probesTidal creek filled/ blockedby rotting organic matter

Figure 10. Schematic illustrating the installation of redox monitoring equipment and contrasting soil profiles at St Kilda. The brown soil layers represent “healthy” mangrove soils that are slowly being eroded away by water flowing (slowly) through the tidal creeks. The creeks are filled with rotting organic matter such as sea-grass and ulva (sapric material) that has become extremely reducing (Eh’s down to –600mV) as bacteria break it down. These soil conditions are “toxic” to the mangrove phneumatophores (breather roots), which have to retreat to “higher ground”. This leaves the creek banks very susceptible to erosion, further restricting the area that pneumotophores can survive. When areas of high ground become too small, mangrove trees are unstable and easily knocked down during storms, killing them.

Supporting the eutrophication hypothesis, we have observed a similar trial that has already been conducted at another site in the Barker Inlet where a bund wall was built to accommodate electricity pylons from the Torrens Island power station some 15 years ago (figure 11). Although the bund wall doesn’t exclude the tide from inundating these mangroves, it blocks a number of tidal creeks that allow the tidal water to flow back out into the Inlet. Seawater and debris carried in by the tide was therefore pooling in the further reaches of the mangroves, becoming stagnant and causing eutrophic conditions and mangrove dieback. In 1990 the electricity commission constructed a drain on the southern side of the bund wall, intersecting the stranded tidal creeks and draining them back into Barker Inlet. This has greatly enhanced the tides ability to “flush” nutrients from the stagnant reaches of the mangrove woodland. In the ten years since the drain was constructed, mangroves have re-established in much of this area.

9

igure 11. Aerial photograph (taken in 1996) of mangrove woodlands (dark green)

educing the amount of nutrients coming into this area, or enabling the tide to flush it

dditional Note:

s Shanti Ditter, (Project Manager) of the Project committee has ceased with the Port

Manager.

F

that were degraded by a the construction of a bund wall (white) that blocked tidal creeks and stopped tidal flushing causing seawater and floating debris to accumulate in the east/ central corner of the photo (near salt evaporation ponds). The increased nutrient load and stagnant water formed eutrophic conditions similar to those found at St Kilda. This condition killed off many of the mangroves in this area and is quite obvious on the above photo. A long shallow drain was dug along the inside (west) of the bund wall about 10 years ago to allow the tide to flush away the stagnant water. Mangroves have now re-established in much of the bare area in the photo.

Rout is one way to raise the Eh of the tidal creek areas and allow the mangrove roots to survive along the tidal creek banks. Improving tidal exchange could be achieved by clearing tidal creek channels, constructing drains and possibly by installing a tidal floodgate in the St Kilda marina bund wall. Ultimately reducing nutrient inputs to St Vincent Gulf and Barker Inlet would be the preferred solution. A MAdelaide Enfield Council and now works for the Holdfast Bay Council. Ms Verity Sanders of Port Adelaide Enfield Council has taken over the position of Project

10

5. Provide a brief description and analysis of Program Performance Indicators as per Item K.

t i his stage, the Project is online to more than meet all of the

ence during this reporting period. We have been able to d

Tweed Heads in

environmental concerns

e general public through the St Kilda Mangrove

cted on 15th of October. The “Totally Wild” program was shown

The project is progressing well. Although the project has not completely me

lestone 4.3 at tMMilestones of Stage 5.

The project has been actively communicating and demonstrating objectives and outcomes to a wider audireach extensive and diverse audience through media, conferences presentation, anseminars, publications of abstracts, posters, and brochures.

Brett Thomas presented the project ideas to an internationally recognised scientific ASS audience at the 5th International ASS Conference held atAugust. The presentation abstract was published in the conference proceedings. A poster and abstract (published in association with the Coastal ASS mapping project,South Australia) were also published in the proceedings.

Channel Ten (Totally Wild) kindly helped us reach the younger audience by interviewing Rob Fitzpatrick and Brett Thomas about the associated with PASS at St Kilda.

An information brochure that also explains the problems at St Kilda is being distributed to school children and thInterpretive Centre.

A field trip to the Gillman site was planned for 24th of September, however this was postponed and conduand Brett Thomas gave a presentation to the Project committee, industry representatives and some BIPEC members. Twenty two people attended the field trip following the presentations. Field notes (in draft from) for the Gillman remediation experiments are being developed for future demonstration days.

11

5.1 Communications and Correspondence made during the reporting period.

o Channel Ten TV program “Totally Wild” aired a segment about the environmental problems being faced by the St Kilda mangroves, on the 3rd September 2002. Brett Thomas and Rob Fitzpatrick were interviewed for a story about their environmental monitoring and the predicted effects of pollution on the mangroves and greater marine environment. For a copy of this segment, please contact Channel Ten’s Totally Wild Program or Brett Thomas. A copy of the segment will be supplied to the Mangrove Interpretive center.

Contents of Appendix 1; Communications

o Abstract: Approaches to remediation of acid sulfate soils in Barker Inlet,

South Australia.. Published in the 5th International CASS Conference transactions. A presentation detailing this abstract was also presented at the conference in August/September 2002 at Tweed Heads. Reference: Thomas B.P., R.W. Fitzpatrick, R.H. Merry, W.S. Hicks and P.G. Davies (2002) Approaches to remediation of acid sulfate soils in Barker Inlet, South Australia. 5th International Acid Sulfate Soils Conference, Tweed Heads, NSW, 25th to 30th August 2002. Book of extended abstracts p 67-68.

o Oral Presentation: Approaches to remediation of acid sulfate soils in

Barker Inlet, South Australia. This paper was presented by Brett at the 5Th International CASS Conference at Tweed Heads on the 30th August 2002.

o Abstract: Properties and distribution of South Australian coastal sulfate

soils and their environmental hazards. Published in the 5th International CASS Conference transactions. A poster detailing this abstract was presented at the conference in August/September 2002 at Tweed Heads. Reference: Fitzpatrick R. W., P .G. Davies, B. P. Thomas, R. H. Merry, D. G. Fotheringham and W. S. Hicks (2002). Properties and distribution of South Australian coastal acid sulfate soils and their environmental hazards. 5th International Acid Sulfate Soils Conference, Tweed Heads, NSW, 25th to 30th August 2002. Book of extended abstracts. p. 40 –41.l

o St Kilda Information brochure: Information on the environmental

conditions at St Kilda (aimed at higher level Primary School and Secondary School students).

o Poster presentation: Properties and distribution of South Australian coastal

acid sulfate soils and their environmental hazards. This abstract was presented as a poster at the 5th International CASS Conference transactions. August/September 2002 at Tweed Heads.

o Field notes: (in draft from) for the Gillman remediation experiments are being

developed for future demonstration days.

12

o Coastal Acid Sulfate Soils Information brochure: A draft brochure detailing the characteristics, identification, hazards, processes and remediation options is currently being drafted. It is being aimed at industry level employees and higher-level secondary students. This brochure will compliment the “Development Brochure” required for dissemination to the public in Stage 5.

5.2 Appendix 2 Project Committee Meetings Minutes. Agenda, minutes and attachments from committee meetings:

o 12/07/01 o 19/09/01

5.3 Appendix 3 Licence Agreement and related documentation

o Licence Agreement (FINALISED). 5.4 Appendix 4 Electronic copy of Stage 1, Stage 2, Stage 3 and Stage 4

Progress (Milestone) Reports on CD.

o CD – Approaches to remediation of acid sulfate soils in Barker Inlet Progress Reports for Stages 1, 2, 3 & 4

13

Declaration As the Organisation referred to in the Financial Agreement we declare that the information given in this report is complete and correct. We consent to the public disclosure of the information in this report.

Signature of authorised representative of recipient organisation

Printed name Ms Verity Sanders Position in Organisation Port Adelaide Enfield Council Contact Telephone Number 08 8405 6727 Date 30/10/2002

14

CASSP

Statement of Expenditure

Project Title (use the same title as in original project application)

Demonstrating amelioration of Acid Sulfate Soils, Barker Inlet Gillman, area South Australia

Name Of Organisation Port Adelaide Enfield Council

Project Start Date 01 / 01 /2001 Expenditure up to 30 / 09 / 2002

Amount of CASSP funding received $

For financial year/s 2002-2003

Expenditure Items as per agreed budget CASSP funds Other funds See attached sheet (hard copy) $ $

TOTALS $ $

DECLARATION I hereby certify that all moneys paid under the financial agreement have been expended or incurred by way of expenditure solely upon the project and in accordance with the terms of the Financial Agreement

Signature of authorised representative of recipient organisation Printed name Position in Organisation Contact Telephone Number Date 30/10/02

15