Bad_Developers

At the local level, the issue of radionuclides was actually mentioned briefly in the Channel Deepening Project SEES, but you could be forgiven for not noticing it because it is buried in one of the SEES reports (Appendix K of Technical Appendix 36), and nothing was done to investigate it further, despite the fact that it is a mandatory requirement of the National Ocean Disposal Guidelines. This work was funded by the Melbourne Water Corporation, not the Port of Melbourne Corporation. It was part of the 1996 CSIRO Port Phillip Bay Environmental Study that the PoMC chose not to pursue further.

To quote briefly from the report: “In this study these three radionuclides were measured in sediment cores collected from two locations in Port Phillip Bay. The locations were nominated by the Port Phillip Bay study management team. One location was near the centre of Port Phillip Bay and this is called the Mid-Bay site. It is located in the deep central basin which is the final collecting area for catchment input of fine sediment and also endocthonous organic production. The second site was in the northern part of the Bay and is called here the North-Bay site. The sediments in this area tend to show the influence of inputs from the Yarra River.”

“The occurrence of low but measurable concentrations of caesium-137 from the surface to 25 cm depth in the 1995 core indicates that the 1953/1956 boundary, corresponding to the years of atmospheric nuclear weapons testing, lies below this depth. The depth of recent mixing in the 1995 core is about 10 cm. The vibracore results for caesium-137 show this radionuclide being detected above 30 cm but not below 40 cm (allowing for about 10 cm being lost on collection).” Since the channel deepening project is intending to deepen the channels by a couple of metres, this work should have been pursued further.

April 21 2008: Yarra River Toxic Dredging Starts

2.1 million cubic metres of toxic sludge from the Yarra River mouth to be dumped in the Bay!

March 23 2008. Note sediment plume drifting south from near Hobsons Bay Channel during a high pressure 'long spell'. Images courtesy of bluewedges

March 17 2008 Note sediment plume associated with toxic waste bund construction near Hobsons Bay

Send Garrett an email

April 5 08: Dredging Starts at the Heads

Mar 3 08: Bulky Queen Leaves Bayside Seriously Browned Off

Dutch 'Death' Ship - Queen of the Netherlands arrives 29/1/08.

For a more thorough analysis of the Bay Dredging Issue please go to the Bluewedges website here

The Company employed to do the Port of Melbourne Corporations' "Dirty Work". Who are Royal Boskalis Westminster nv?

Who are the masterminds behind this "insane" plan? (PoMC)

also here Australian Council for Infrastructure Development & here

Toxic Nightmare

Beaches in Inner Melbourne likely to be most impacted by toxic plume from Yarra River Dredging (above). Sandridge Beach and Port Melbourne (Beacon Cove)likely to suffer the brunt of the toxic soup.

Yarra River near Southbank is affected by tidal flows. In certain conditions dredge spoil may also be washed back up the Yarra creating a toxic soup that may reek to high heaven. Have residents and businesses been informed of this possibility by the State Government? What impact will years of dredging have on tourism in Melbourne?

Beacon Cove beach likely to be heavily impacted by at least 1.5-2.5 mg/L toxic sediment plume containing dozens of toxicants (This is a conservative estimate!)

Docklands will suffer from toxic sediments and most likely smell.

Turbid water will occur upstream of Bolte Bridge

Feb 08: Black Bream caught near Docklands. The Yarra River does support a variety of marine life, even in its lower section.

Yarra River downstream of Bolte Bridge. All of this area will be dredged.

2.1 million cubic metres of toxic sludge from the Yarra River mouth to be dumped in the Bay!

Approximate location for toxic sediment sites. Site will be bigger than Nowingi and will be underwater!

At Most Risk Beaches in 'Inner Melbourne'

Yarra River Concerns

Other threatened beaches here

Photo: The Age Craig Abraham (Sep 2005)

Bay Dredging Likey to Affect Beachgoers ( The Age 4/9/07)

2. Dredging the Yarra (Jun - Aug 2008 (Toxic Spoil in Yarra) & Jan - May 2009 ("non-toxic" spoil in Yarra)

1996 CSIRO image of Yarra Plume Image (below)

"This image, taken from the cover of a 1996 CSIRO Report, shows a turbid flood plume from the Yarra. It can be seen that the plume extends from Williamstown to beyond Ricketts Point. If the plume contained toxic sediments from dredging, the bay and beaches from Williamstown to beyond Ricketts Point could be affected. Fishing and swimming may have to be banned. Currents in the bay are driven by wind, so that depending on wind direction, plumes from the Yarra can go down the east side of the bay, or across to the west past Altona."

Estimated contaminated spoil plume Yarra River

Toxicants included in sediment plume from Yarra River dredging most likely to include;

(Please note: Radionuclides were not looked for by PoMC. In fact PoMC used an old study which indicated very low radionuclide levels, but the sampling sites were nowhere near the ship channels! Cobalt 60 and Caesium 137 could be expected to be found in the river channel, and there could be hotspots elsewhere, the legacy of visits from nuclear-powered ships. Dioxins were not looked for either, though bound to be there).

Inorganics: Antimony, Arsenic, Barium, Beryllium, Cadmium, Chromium, Cobalt, Copper, Lead, Nickel, Selenium, Silver, Tin, Zinc, Mercury, Total Cyanide, Ammonia as N, Nitrite + Nitrate as N (Sol.), Total Kjeldahl Nitrogen as N, Sulphate as SO4 2-, Sulphur - Total as S (LECO), Fluoride, Sulphide as S.

Organics: Total Organic Carbon, Tributylin, TPH C6 - C9 Fraction, TPH C10 - C14 Fraction, TPH C15 - C28 Fraction, TPH C29 - C36 Fraction, TPH C10-C36 Fraction, Benzene, Toluene, Ethylbenzene, meta-&para-Xylene, ortho-Xylene.

Phenols: 2-Chlorophenol, 4-Chloro-3-Methylphenol, m-Cresol, o-Cresol, p-Cresol, 2.4-Dichlorophenol, 2.6-Dichlorophenol, 2.4-Dimethylphenol, Hexachlorophene, 2-Nitrophenol, 4-Nitrophenol, Pentachlorophenol, Phenol, Tetrachlorophenol, 2.4.5-Trichlorophenol, 2.4.6-Trichlorophenol.

OPPs (Organophosphorus Pesticides): Bromphos-ethyl, Carbophenothion, Chlorfenvinphos (E), Chlorfenvinphos (Z), Chlorpyrifos, Chlorpyrifos-methyl, Demeton-S-methyl, Diazinon, Dichlorvos, Dimethoate, Ethion, Fenamiphos, Fenthion, Malathion, Azinphos Methyl, Monocrotophos, Parathion, Parathion-methyl, Pirimphos-ethyl, Prothiofos

Estimated spoil plume at Port Phillip Bay heads

Summary of Predicted Fauna data

At Most Risk Beaches from Yarra River toxic plume.

(Beaches threatened at the southern end of the Bay due to dredging activities include; Nepean Bay, Ticonderonda Bay, Sorrento, Tootgarook, Rosebud, McCrae, Dromana, Safety Beach, Mount Martha, Mornington, Point Lonsdale, St. Leonard's).

Sandridge Beach. 1.5-2.5mg/L+ Toxic Sediment Plume to hit this beach during dredging.

Sandridge Beach. Even the most conservative estimate predicts that this beach will suffer from dredge pollution.

Beach at Beacon Cove 1.5-2.5mg/L+ Toxic Sediment Plume to hit this beach during dredging.

Beach at Port Melbourne at risk if winds blow onshore during and after dredging

Yarra River Concerns

I HOPE that all business proprietors and residents who live and work in close vicinity to the lower Yarra River are having a serious look at the dredging of the bay and the Yarra. The dredging plan will also see several kilometres of the river dredged up to Bolte Bridge. This dredging will release some of the most toxic substances known anywhere. It will most likely also release highly offensive smells.

The Yarra is an estuary from Hobsons Bay to Dights Falls in Collingwood. Tidal currents could facilitate the movement of highly toxic and strong-smelling sediments upstream from Bolte Bridge, past the CBD for several kilometres. Friends of the Earth,

Aerial view of Yarra River. Yellow dot marks Dights Falls, which is where salt water and fresh water meet on the Yarra River. The green dot marks the Princes Bridge where a waterfall (until 1880) once marked the limit of salt water 'intrusion' into the Yarra River. The scarlet line indicates a rough line where the Yarra dredging will occur, ending at Bolte Bridge. The Yarra estuary extends for 22km from Hobsons Bay to Dights Falls. All of the estuary could be impacted. The red dot indicates the Punt Road Bridge.

Under certain conditions it is not inconceivable that sediment tainted water could flow upstream, carried by tidal currents and winds, past the CBD of Melbourne, possibly through to Dights Falls. What will be the odour caused by digging up toxic sediment that has laid at the bottom of theYarra River for up to 160 years? This scenario could well play out particularly in times of low flow on the Yarra - ie times of low rainfall (summer-autumn).The stench could be overwhelming for businesses and residents along the Yarra.

Melbourne Times November 7, 2007 p7

"Expert warns: bay dredging could cause stench by Bianca Hall

Dredging the Yarra and channels in Port Phillip Bay will stir up more than 160 years worth of industrial waste and create foul odours that will waft through the city, Richmond, Abbotsford and Hawthorn, according to Friends of the Earth.

Environmental researcher Anthony Amis has been examining the health of Melbourne's waterways for Friends of the Earth and says the impacts of dredging will extend far beyond the port areas.

Under a plan by the Port of Melbourne Corporation, given conditional approval by the Government last week, bay shipping channels and Hobsons Bay would be deepened to accomodate larger container ships.

But Mr Amis said while there had been a lot of debate about the effects of dredging on the bay, little attention had been paid to the health of the Yarra and its tributaries.

"Imagine the stench created by stirring up combined effluent of 160 years of industrialisation," Mr Amis said. "These sediments are contaminated with almost every toxic substance known to humanity."

The Yarra river up to Dights Falls is a 22km estuary, with a combination of salt and fresh water.

Mr Amis said water flowed both downstream and upstream, and salt water was confined by the falls at Abbotsford.

He said Yarra flows heading upstream, which were mainly affected by tides in the bay, increased during storms or sea rises at Williamstown. During these times, downstream flows in the Yarra heading towards the bay slowed down.

"It is not inconceivable that in times of low Yarra flows, particularly in autumn and summer, great amounts of recently dredged , foul-smelling toxic sediment could actually washe back up the Yarra River, past Crown Casino, past Southbank, past the Tennis Centre and ultimately all the way past South Yarra, Richmond and Hawthorn," Mr Amis said.

Yarra River near The Warmies north of Williamstown. At risk of toxic soup at 15-17.5mg/L at this location. The Yarra River estuary is also impacted by the water fluctuation of Port Phillip Bay. Sea level fluctuations can be as large as 0.8m at Williamstown over 3 days. Storms can also cause sea level fluctuations.

Dredging after-effects: rivers run through it

PROPOSED dredging in Port Phillip Bay and in the Port of Melbourne could also create a stink in the Yarra and Maribyrnong rivers, with tidal surges forcing smelly sludge upstream as far as Abbotsford, say anti-dredging groups.

The Port of Melbourne said that its extensive modelling showed the problem would not eventuate, but Monash University says it might.

The Government has already admitted the $770 million dredging project, which is expected to start in January, could affect beaches all along the bay, including Port Melbourne and Williamstown.

However, the environmental group Friends of the Earth, which opposes channel deepening, said the toxic sludge unearthed in the dredging could wash upstream as far as Dights Falls, Abbotsford, because the Yarra is a tidal river.

A spokesman for Friends of the Earth, Anthony Amis, said that industrial refuse such as heavy metals and other toxins would be dredged up in the channel-deepening process and could easily wash upstream.

"The Port of Melbourne Authority claim that the toxic plume will only spread as far as William Street," said Mr Amis. "In times of low flow, sea water can go as far upstream as Dights Falls, (as) the Yarra estuary is actually 22 kilometres long.

How on earth will the sediment stop at William Street if it's flowing upstream on a strong tidal current?"

Mr Amis said that 3 million cubic metres of sediment would be dredged from the Yarra up to Bolte Bridge. "The sediment contains many heavy metals and other toxins (and) the smell of the exposed sediment could well be very nasty. I fear that these toxins may wash up back the river past the CBD into the Yarra near Hawthorn and Richmond."

Mr Amis said a 1982 paper published in the Australian Journal of Freshwater Research showed how far salt water from Port Phillip Bay could wash upstream, with salinity detected "beyond Bridge Road".

The paper, Water Movement and Salinity in the Yarra, stated that "the tidal influence in the Yarra and Maribyrnong estuaries is very dependent upon weather conditions … when a sudden increase in water level occurs at Williamstown as a result of storms in Port Phillip Bay, water is forced up both estuaries increasing water level in the estuaries".

A Port of Melbourne spokesman said the Yarra was "tidal, like any river" but "our modelling would not suggest that (a tidal plume)".

Yarra River near the Warmies. The flow pattern of bottom water can be quite different to surface water. Writing in 'Water Movement & Salinity in the Yarra and Maribyrnong Estuaries' (Australian Journal of Marine and Freshwater Ecology, 1982 33, 401-15)'; "For part of the time the bottom water moved upstream with a velocity as high as 24cm s-1, and at other times moved downstream with maximum velocities reaching 10cm s-1...During the survey there was a net movement of saline water upstream past Punt Road, corresponding to the general increase in water level... The tidal influence in the Yarra and Maribyrnong estuaries is very dependent upon weather conditions... It seems that when a sudden increase in water level occurs at Williamstown as a result of storms in Port Phillip Bay, water is forced up both estuaries increasing water level in the estuaries. Subsequently, as the level at Williamstown drops the water banked up in the estuaries is able to flow with high velocities out towards the bay...With medium river flows such as occurred on 12 July, the tip of the salt wedge penetrated to somewhere between Punt Road and Bridge Road - approximately 15km upstream from Hobsons Bay..."

October 7 2007: Blue Wedge rally under the West Gate Bridge near the Yarra River.

Yarra River Estuary at Bridge Road Hawthorn/Richmond under threat from dredging plumes carried by tides?

Beaches Threatened by Toxic Plume from Yarra River Mouth Dredging could include;

also, Middle Park Beach, Port Melbourne, Sandridge Beach, Williamstown Beach, Altona Beach

Send Garrett an Email

"Your Dreamworld is Just About to End"

Mar 28: Melbourne DredgingOpponents Lose Case

Feb 21: Dredge Protest Group Deal Bitter Blow

Feb 7: Garrett signs off on Environmental Management Plan

Jan 23: Garrett to Face Fresh Dredge Case 23/1/08

Send an email to Federal Environment Minister and ex lead singer of Midnight Oil Peter Garrett

"Slightly less virulent but just as tireless and more influential in the pop music culture are those who wield their "compassion" as a weopon against the middle class and its perceived politik. This mask of compassion makes the pathology sellable to that very middle class. Springsteen, U2, Midnight Oil, Sinead O'Connor, and Sting currently exploit this angle most effectively" p72 Rock and the Pop Narcotic Joe Carducci 1990

Doctors Concerned About Yarra Dredging 11/3/08

New Review Planned for Dredging 27/2/08

National Blockade Hits Peakhour Traffic 19/2/08

Catastrophe Warning Over Channel Works 18/2/08

1000+ rally at Rosebud 18/2/08

No Compo From Dredging 12/2/08

Dredging Destroying Scallops 10/2/08

Protesters fined as dredging begins 8/2/08

State Bullied Over Port 2/2/08

Contract a Secret for Three Years 1/2/08

Don't Dredge the Yarra 30/1/08

$500 million bill for dredging 29/1/08

Blue Wedges on US watch list 27/1/08

It's Time to Dredge Up a Few Secrets 26/1/08

Toxic Shocker 24/1/08

Scientists Question Yarra Toxic Sediment 21/1/08

Bay Hit By Fish Health Scare 18/1/08

7.30 Report 8/1/08

Counter terrorism-police-seek-meeting-with-bay activists 16/1/08

D-Day for Bay as Last Legal Hurdle Falls 15/1/08

Call for Garrett to Halt Toxic Dumping 10/1/08

Channel Deepening Delay to Affect Bay Beaches 9/1/08

Baywatch Reveals Swarms of Unknown Life 9/1/08

Vigil as Port Phillip Bay Dredging Case Nears 9/1/08

Last Minute Challenge to Bay Dredging 6/1/08

Fruit of the Plume Leaves Portsea Paradise Lovers Fretting 6/1/08

In Depth Battle For The Bay 6/1/08

Bay dredge court fight to go ahead (age) 6/12/07

Dredging After-effects: rivers run through it (sunday age) 18/11/07

Protest hopes to give dredging big wedgie (age) 17/11/07

Dredge Threat to Beaches (sunday age) 11/11/07

The Port of Melbourne Corporation (PoMC) is asking Victorians to take a huge environmental and social gamble, merely so that a number of ships entering the Bay can load to full capacity.

The Southern waters of Australia, including Port Phillip Bay has the highest diversity of marine species anywhere in the world. 90% of species occur NOWHERE else on earth! Many of those species have not even been fully studied - and yet, before we understand our beautiful local underwater world, we are being asked to sanction its destruction - merely so that some larger ships can enter the Bay fully laden.

What is at stake? The PoMC is sanguine about the 180+ threats in the proposed channel deepening - but their suite of consultants will have moved on well before the consequences hit!

129 "extreme" or "high" environmental threats are listed for our Bay - why should we be asked to consider ANY risks - let alone 129 serious and 54 moderate threats? Are we offered over 180 seriously or moderately good economic reasons to go ahead with the project? NO !

The EES proposes Environmental Management via a complex "self-regulation" model - an alliance between the Proponent and the international, privately owned Dredging contractors. The EPA is relegated to an "advisory" role it seems. Has self-regulation been a great success for the environment in the past? This project is purely about moving boxes around the Nation.

Do we risk our Bay and beaches for a 19th Century parochial response to a 21st Century national issue?

This letter conveys to you my final conclusions concerning the review of the final Port Philip Bay Environmental Effects Statement undertaken on your behalf.

I have now read most of the final EES documents for the proposed channel deepening of Port Philip Bay (PPB) and had a series of discussions with the project proponents and their consultants to clarify particular issues. My general impression is that these final documents are much improved from the preliminary documents released earlier in the year. Many of the points raised by my earlier criticisms have now been covered. Some of the underlying science is still incomplete but the state of the art in physical and ecological modelling, coupled with fundamental uncertainties in calibration and validation data ensure that it is simply not possible to eliminate all the potential uncertainties. The science required by this EES is at the forefront of environmental science - and while we can anticipate some of the potential risks, there will always be uncertainties. In particular it is not possible to predict all of the potential long term ecosystem impacts of the short term dredging program. The final EES is therefore set in a risk management framework - which is appropriate. Furthermore the EES acknowledges that not only are there risks in the carrying out of the project, but also that there are residual risks which cannot be mitigated by appropriate risk management in the context of an Environmental Management Plan (EMP). [It should be noted that the final EMP will not be agreed until after the Independent Panel has handed down its decision.] Society needs to have a debate about whether these residual risks are acceptable given the overall costs and benefits of the project.

I do suugest that there could have been greater transparency in the documentation. It required detailed reading of about 30kgs of documents (equivalent on CD-ROM) to find some of the key statements. The summary document does not fully acknowledge the initial and residual risks - and like many other documents produced by the project proponents tends to put an optimistic gloss on the whole project. While the original key features summary reports and appendices were in many respects insufficient to determine if the necessary modelling and integration had been done, the new EES documentation is reasonably complete and does address many of the necessary issues. Most of the concerns raised in my previous report have been covered in the new documentation. Yes, there are still a few minor points that can be raised, but, overall, there is enough there now to be able to identify and assess most of the risks. The final EES does contain sufficient references to the scientific literature and is aware of the "state of the art" in various disciplines. The debate has moved a significant way forward since the initial documents. The EES does, I believe, put to rest any concerns about tides, changes in sea levels and wave height effects. I have never believed that these are likely to be major issues. Given the small effect overall on the geometry of the Heads (in terms of tidal exchange, a small deepening of an already modified shipping channel) then the changes to the physics of the Bay are not likely to have significant impact. The EES report uses the word "imperceptible" - I am not sure if that is the work I would have used but nevertheless, the effects are likely to be small. I am also of the opinion that the potential effects of oil spills, noise, lights at night, aesthetics etc. are also not major, and will be of short term impact. While there may well be significant short term effects (and a nuisance created), the EMP will be capable of managing these effects. Equally the EES discusses the potential risks of introducing more exotic species to the Bay and proposes suitable management actions. These are risks but they are, in my view, manageable.

There is an important acknowledgement in the EES that there will be risks to the Bay as a whole (e.g. disturbance to the N cycle in the Bay as I predicted in my earlier paper) and that there will be risks to particular assets (e.g. National Parks at the Heads and Mud Island, diving, ecotourism) and species (e.g. sea grasses, penguins, dolphins, various species of fish etc.) There are, whether we like it or not, fundamental uncertainties around the long term implications and impacts of the short term insult to the Bay through dredging. Both the EES and the project proponents publicly acknowledge the uncertainties and risks and they are concerned about them. The final EES does now accept that there will be impacts on Bay-wide processes of Nitrogen cycling and denitrification and the figure arrived at (an effective increase in load of 250 tonnes of Nitrogen) is not significantly different from the estimates arrived at in my previous paper. There has been some debate about the possible impact of this change to the overall nitrogen cycle in the Bay. I still feel that this change is significant - at least during the period of dumping and for a while afterwards. There are risks here, especially if the dredging period happens to correspond to a period of higher than normal rainfall, and there remain residual issues about recovery times for benthic processes after they have been smothered by the dredge spoil.

The major impact of the Bay is going to be the effects on ecosystems, species and ecological processes arising from the suspended sediments stirred up by the dredging itself and disposal of the dredged material. In particular, there are long term unassessed risks to the National Park ecosystems at the Heads, to fish etc and to the sea grass beds in the Southern part of the Bay. These arise from smothering and light penetration reductions through plumes of sediments and the increased water turbidity. This is where there are acknowldged to be "extreme" or potentially "catastrophic" risks of long term damage to the Bay from the short term dredging activities. The possibility of hysteretic effects (points of no return) is real.

The EES speaks of regeneration and recovery times of up to 10 years - this may be optministic in the case of sea grasses in the Soutern part of the Bay. The final EES acknowledges that the base case modelling of the dredging indicated that risks to the ecosystems in the Southern part of the Bay were not acceptable. The reason for this is the fact that while tidal and wind driven currents are low in the Northern part of the Bay (and hence sediment plumes from dredging and dumping will not travel far), in the Southern part of the Bay, where tidal streams are strong, the sediment will be widely dispersed. The modelling to support the risk analysis in this area is not complete in the final EES but the proponents argue (and I accept their arguements) that the modelling is adeqaute to define some broad risk categories and guide the EMP. There always will be uncertainties in the generation of sediment plumes, their disposal and in the ecosystem impacts of the dredging activities. The problem we have is that it is not possible to collect data on the dredge (in terms of the generation and dispersal of the sediment plumes) until it is actually operating in the Bay. There are significant uncertainties surrounding the actual performance of the equipment in situ and this means that any predictive modelling will inevitably be fraught with uncertainty. Dredging the shipping channels in the Great Sands and through the Heads therefore poses significant risks to the ecosystems, seagrasses, biodiversity and fish (and the National Parks) around the Heads. I acknowledge that a risk management framework takes care of this - and relies as best we can on expert judgements (indeed the models are no more than codified expert judgements). I do also acknowledge that there are fundamental uncertainties in the science in this area so that even further improving the models would leave significant risks. Given this, the hydrodynamic and ecosystem modelling is adequate to the task (not perfect, but fit enough for purpose). So we probably have enough to go on with the reports we have. There are, no matter what, residual uncertainties in all this. Therefore, it is acceptable for the EES to categorize this as an area of significant risk both to the environment and to the project.

The EES asserts that the proposed Environmental Management Plan (EMP) and an adaptive management regime will suffice to reduce these to "moderate" or manageable proportions. The precise natures of the EMP and of the adaptive management plan are yet to be fully determined. As David Fox has pointed out, the risk assessment framework used, whilst adhering to Australian Standards 4360 methodology, does treat the potential risks one by one. The specialists employed were asked to rate the likelihood and the consequences of risk for each ecosystem or species - penguins, fish and seagrasses - seperately and did not necessarily use commensurate scales. Furthermore it seems that some of the extreme risks were rated as only "moderate" on the basis of being extremely unlikely. What increases the overall risk of ecosystem damage is lack of integration of associated risks - e.g. if we lose the seagrass beds then we will also lose the associated fish that require seagrasses for recruitment; and so on. This takes the discussion into the region of cumulative impacts - a difficult area for which there are methods.

The risk assessment and risk management framework used in the final EES accepts that there will be residual risks and identifies them. The greatest long term risks are to key ecological assets in the Southern part of the Bay. It is here that we have National Parks, high biodiversity, key species, high aesthetic values and eco-tourism activity.

*Do the benefits of the proposed project exceed the acknowledged risks - in particular the "residual" risks and the uncertainties? The National Parks around the Heads and at Mud Island seem to be particularly at risk. Is this acceptable? Because there is no definitive scientific answer to this question, it is debate that society must have.

*Is the precise form of the proposed EMP sufficient to reduce the base case risks to acceptable levels? Will adaptive management of the dredging serve to mitigate the evident risks? In my view we need more transparency and debate on this issue. For now, we have to take a lot as read in this regard.

*If the project goes ahead, what kind of monitoring program (and technology) can provide the kind of information that will be required on a day to day basis to manage the dredging project from an environmental point of view? What form of public scrutiny, disclosure or transparent audit process can we then put in place to give comfort to those who doubt that the project can proceed without acceptable risk?

There is little more than science can do to resolve these issues other than to provide "decision support" to the community in the form of an ongoing monitoring and adaptive management framework should the project go ahead. The final EES recognizes that there are risks associated with the project - it is now a matter for the Melbourne community to decide if, on the balance of probabilities, the project is worthwhile.

The Newport power station, a major contributor to the national electricity grid, could be forced to shut down during the proposed $545 million Port Phillip Bay channel deepening project.

Operator Ecogen Energy says an environmental effects statement on the project does not identify the risks to the power station, which supplies electricity during peak demand periods such as heatwaves.

The 500-megawatt station on the west bank of the Yarra River pumps water from near the mouth of the river to cool its turbines, then returns warmed water to Hobsons Bay.

Ecogen Energy general manager John Edelsten said if the water contained contaminated sediment dredged up during the channel deepening, the Environment Protection Authority could revoke the power station's operating licence.

The EPA licence specifies limits for temperature, flow, acidity, iron, ammonia, chlorine, carbon, nitrate, turbidity and dissolved oxygen.

Mr Edelsten also said if the sediment contained high levels of sulphide it could corrode tubes in the power plant, forcing the station off line. "These are all unknowns. That is why we are so concerned about all of this and seek assurances that these things won't impact on us," he said.

If the station were shut down there would be power shortages in peak periods and that could lead to blackouts across the state, he said.

The $12 million environmental effects statement, which found that the dredging of Port Phillip Bay's channels would have no long term ill effects, is the biggest undertaken in Victoria.

But an Ecogen submission to a Government-appointed panel says the study does not cover the potential effects on the power station.

Power blackouts could have serious economic effects on the state, it says. "One only need consider the impacts of the Longford gas explosion."

The submission raises concerns that fish at one of Melbourne's most popular angling spots, known as "the Warmies", could become contaminated as a result of the dredging stirring up polluted sediment. The Warmies is the colloquial name for the power station's cooling water outlet, where warm current expelled from the plant attract shoals of tailor fish.

Ecogen's submission said the risk of fish contamination required further investigation. "In the event of any risk being posed to thrid parties, Ecogen would request indemnification from the state," the submission says. "We ask the panel to call upon the Government, via its Port of Melbourne Corporation, to take all necessary steps to ensure that none of the identified occurrences which would jeopardise the operations of Newport Power Station come to pass."

Mr Edleston said Ecogen was not opposed to the channel deepening provided there were proper controls.

Past reports

" . . . Sediments in the Port of Melbourne contain elevated concentrations of copper, nickel, lead, zinc, mercury and petroleum hydrocarbons compared to both Bay-wide sediments and to sediment quality guidelines published in scientific literature. Concentrations of butyltin compounds are generally low, however some sediment samples contained very high concentrations. Dumping of these sediments on the spoil ground located in the northern part of the Bay has resulted in elevated concentrations of metals and petroleum hydrocarbons in the spoil ground sediments. The concentrations of nickel and mercury in parts of the spoil ground are such that they could cause adverse biological effects to biota inhabiting the sediments. It is unlikely that leaching of dissolved toxicants from the sediments into the water column during dredging operations is significant. The annual loads of metals such as cadmium, copper, lead and mercury transported from the Port of Melbourne to the spoil ground is less than the annual load that enters the Bay from rivers, streams and drains. . ."

Maintenance dredging to remove accumulated sediments is periodically carried out in dock areas and along shipping channels in Port Phillip Bay. Maintenance dredging by the Port of Melbourne and Port of Geelong authorities involves the dredging and subsequent dumping of more than 500,000 m3 of material annually (Batley 1992). Capital works dredging programs create additional volumes of sediment that are translocated from one part of the Bay and deposited on spoil grounds in another part of the Bay. Dredged sediments - particularly those from Port areas - may contain elevated concentrations of heavy metals, petroleum hydrocarbons, polynuclear aromatic hydrocarbons (PAH) and antifouling paint constituents. During dredging and dumping operations there is the potential for a proportion of these contaminants to be remobilised into the water column. Transport of substances released into the water column can adversely affect biota located in areas away from the dredging and spoil ground sites. . ."

". . . In the Port of Melbourne cores the concentrations of cadmium, chromium, copper, nickel, lead, zinc and mercury are consistently higher than the concentrations of the corresponding elements in cores collected from relatively uncontaminated areas of the Bay during 1993 (Fabris et al. 1994). Additionally, unlike the Bay core samples in which concentrations of copper, lead and zinc decreased with increasing depth, the metal and organics concentrations within the Port of Melbourne core segments did not change appreciably with depth. Dredging in the Port of Melbourne is carried out using a cutter-suction dredge that typically removes a 30 cm thick layer of material. Therefore the material that is deposited at the spoil ground would consist mostly of material contaminated with metals and organics having concentrations greater than those that occur in Bay sediments generally..."

p10 " *spoil from Port of Melbourne dredging operations has been dumped predominantly in the northern half of the spoil grounds, and;

*The surface (0-40cm) sediments of the spoil ground as a whole have progressively become more contaminated with cadmium, copper, lead, zinc and petroleum hydrocarbons compared to the surrounding Bay-wide sediments."

Table 2 (below). Comparison of toxicant concentrations in sediments from Port of Melbourne, spoil ground north and spoil ground south using Duncan's multiple range test (alpha=0.05 and confidence=0.95). The Type III SS general linear model significance level P is indicated. Tests were performed on natural logarithm transformed data. Values in the Table are arithmetic squares means. Data are ug g-1 dry weight (Fe is %).

a. for each variable, areas with the same superscript letters are not significantly different from each other. Common superscripts (e.g. AB) indicate that the mean at that area was not different to the means of either of the other two areas.

b. Long et al. (1995). ERL - Effects Range Low designated the lower 10th percentile of biological effects data. ERM - Effects Range Median designated by the 50th percentile of effects of biological effects data.

c. mean TBT for Port of Melbourne is 0.032 ug g-1 if two high values from Swanson Dock core (Appendix 3) are excluded

p11 "... The sediments from the Port of Melbourne area contained concentrations of copper, nickel, lead, zinc and mercury that exceed the 10th percentile of biological effects data (ERL, Table 2). The sites from the northern half of the spoil ground contained levels of nickel, lead, zinc and mercury that exceed ERL data. Nickel and mercury from all three areas exceed the ERL data. However, none of the areas exceed the 50th percentile of biological effects data (ERM, Table 2)..."

p13 "... The top 20 cm of sediment from the Swanson Dock (Site 4, Figure 1) and from the spoil ground (Site 7, Figure 2) were among the most contaminated in terms of metal petroleum hydrocarbons and butyltin compounds... To asses whether any of the contaminants present in these sediments could be readily leached into the water column during dredging and disposal operations the sediments were subjected to an elutriation test as specified in the Victorian Trial Dredge Protocol (EPA 1992, Schedule A). The weight to weight ratio of water sediment specified by the Protocol is 4:1. The metals results for the Swanson Dock sample ... were comparable to Bay-wide concentrations of dissolved metal species (Fabris and Monahan 1995). The butyltin data were also very low, and the TBT concentration was below the detection limit. The elutriate from the spoil ground site had higher concentrations of most of the metals, TPH and butyltin compunds than the Swanson Dock sample. The high iron concentration in this sample suggests that the elevated concentrations in this elutriate sample might be associated with fine suspended matter that passed through the 1 um pore size glass fiber filters used to filter samples."

p14 "Overall, the results of the elutriation test carried out during this study were lower than previously reported for samples from the Port of Melbourne area... On the basis of the results from the present study (and taking into account the dilution factors that are involved) it is unlikely that any dissolved metal, TPH and TBT species that might be released into the water column during dredging or disposal of the sediments at the spoil ground will significantly alter existing concentrations of dissolved species of these substances in the water column.

However, since the sediments dredged from the Port of Melbourne consist primarily of fine material, it is likely that contaminated suspended matter resulting from the dredging and spoil dumping operations could remain in the water column (as evidenced by the results of the elutriation test of the spoil ground sediment) long enough to be transported further afield than the immediate dredging or dumping area..."

"On average, maintenance dredging in the Port of Melbourne removes about 200,000 m3 to 250,000 m3 of material annually. Additional material may be occasionally dredged because of capital works programs (Captain Tim Muir, PMA, pers. comm). Table 6 shows that between 1987 and 1994 an annual average of 335,063 m3 of material was dredged from the Port of Melbourne. All of this material was deposited in the Port Phillip spoil ground (Figure 2). Most of the dredging (78%) during this period was carried out in areas north of the Westgate Bridge. All of the sediment samples for the Port of Melbourne study were collected north of the Westgate Bridge."

Table 6. Summary data for dredging operations in the Yarra River area of the Port of Melbourne for the period September 1987 to November 1994 a.

p15 "Measurements on three samples indicated that the sediments from the Port of Melbourne contain 540kg of dry material per cubic metre of wet sediment. This value, together with the data from Tables 3 and 6, was used to calculate the annual loads of toxic substances that are transported from the port to the spoil ground as a result of dredging activities (Table 7).

Comparison of the mean annual metal loads contained in sediments dredged from the Port of Melbourne with loads contained in an equivalent volume of Bay-wide sediments shows that cadmium, copper, lead and mercury loads in the Port of Melbourne sediments exceed those in Bay-wide sediments by a factor of three or more (Table 7). TPH loads in the Port of Melbourne sediments are about 21 times greater than the load in comparable volumes of Bay-wide sediments (Table 7). To place these results in perspective, available data indicates that the mean annual metal loads contained in the dredged sediments from the Port of Melbourne (excepting Manganese) are lower than the annual loads of metals that enter the Bay from streams, drains and the Western Treatment Plant (Table 7). Input streams loads for petroleum hydrocarbons are not available at the time of writing, but reported spills (from ships) in the whole of Port Phillip Bay amount to approximately 15 tonnes of oil annually (D.Palmer 1995, Victorian Marine Pollution Committee; pers . comm.)..."

p 15/16 "Maintenance dredging of the shipping channels within the Inner Harbour (Corio Bay) and Outer Harbour (Geelong Arm) has been carried out periodically since the shipping channels were created circa 1854. Cutting of the channels and their maintenance since then has involved the dredging and disposal of about 20 million m3 of material (PGA 1993a). Additional proposed works to increase the depth of the shipping channels from 11m to 12 m will involved the dredging and disposal of about 2.1 million m3 of material from the Inner Harbour and about 3 million m3 of material from the Outer Harbour (Table 8). It is intended that sediments dredged from the Inner Harbour will be disposed of at a new spoil ground within the Inner Harbour and spoil from the Outer Harbour will be disposed of at a new spoil ground located in the Outer Harbour."

Table 7. Estimates of toxicant loads contained in sediments that are dredged or proposed to be dredged from the Ports of Melbourne (annual mean) and Geelong (channel improvement) compared to toxicant loads in equivalent volumes of Bay sediments and estimated annual loads entering the Bay from streams. Units in tonnes.

a. calculated from data in Tables 3 and 6 and assuming 540 kg of dry material per m3 of wet sediment.

b. calculated from data in Tables 3 and 8 and assuming 540 kg of dry material per m3 of wet sediment.

Table 8 Summary data for the proposed dredging operations for the channel improvement in the Port of Geelong a.

p17 "The mean concentrations of toxic substances in the sediments of the Inner Harbour channels are generally higher than their respective concentrations in sediments from the Outer Harbour channels (Table 3). Industrial contamination of the Inner Harbour (Phillips et al. 1992) accounts for this difference. Similarly, the spoil ground sediments from t

Port of Melbourne Authority Bay Dredging

Port Phillip Bay (Nerm).

April 21 2008: Yarra River Toxic Dredging Starts

March 23 2008. Note sediment plume drifting south from near Hobsons Bay Channel during a high pressure 'long spell'. Images courtesy of bluewedges

March 17 2008 Note sediment plume associated with toxic waste bund construction near Hobsons Bay

April 5 08: Dredging Starts at the Heads

Mar 3 08: Bulky Queen Leaves Bayside Seriously Browned Off

Dutch 'Death' Ship - Queen of the Netherlands arrives 29/1/08.

Toxic Nightmare

1996 CSIRO image of Yarra Plume Image (below)

Estimated contaminated spoil plume Yarra River

Estimated spoil plume at Port Phillip Bay heads

Summary of Predicted Fauna data

At Most Risk Beaches from Yarra River toxic plume.

(Beaches threatened at the southern end of the Bay due to dredging activities include; Nepean Bay, Ticonderonda Bay, Sorrento, Tootgarook, Rosebud, McCrae, Dromana, Safety Beach, Mount Martha, Mornington, Point Lonsdale, St. Leonard's).

Yarra River Concerns

Dredging after-effects: rivers run through it

Beaches Threatened by Toxic Plume from Yarra River Mouth Dredging could include;

Send Garrett an Email

"Your Dreamworld is Just About to End"

Mar 28: Melbourne DredgingOpponents Lose Case

Feb 21: Dredge Protest Group Deal Bitter Blow

Feb 7: Garrett signs off on Environmental Management Plan

Jan 23: Garrett to Face Fresh Dredge Case 23/1/08

Past reports