Parliamentary Committees

Public Works Committee: Port Lincoln Wastewater Treatment Plant

Mr CREGAN (Kavel) (11:01): I move:

That the 19^th report of the committee for the Fifty-Fourth Parliament, entitled Port Lincoln Wastewater Treatment Plant Sludge Management Upgrade, be noted.

The committee heard from SA Water that there is a need to upgrade the wastewater treatment plant in Port Lincoln. That plant is located just over four kilometres from the town centre. The committee received evidence that the growth in the Port Lincoln catchment has contributed to an increase in load to the sludge treatment process at the plant.

The committee was informed that sludge lagoons were nearing capacity and that this had contributed in a material way to a number of environmental incidents, and evidence was sought in relation to those incidents. The committee understands that the Environment Protection Authority reviewed SA Water's operating licence and included an environmental improvement program annexure to the Port Lincoln wastewater treatment licence.

The committee also had the benefit of evidence that the proposed upgrade will address the requirements I have outlined to the house and the joint issues of odour and leakage in the old containment lagoons. The committee has been advised that the project proposal received full financial approval from the SA Water board for expenditure in the amount of $18.794 million for the completion of the project, and the estimated time frame for practical project completion is December 2020.

Written and oral evidence regarding the upgrade to the wastewater treatment plant was considered by the committee. SA Water officials provided assurances to the committee that acquittals were received from the Department of Treasury and Finance and the Department of the Premier and Cabinet. The committee heard that the Crown Solicitor had deemed the works and procedures followed by SA Water in relation to the bringing forward of this project to be lawful.

The committee is satisfied that the proposal has been subject to appropriate agency consultation and also meets the criteria for examination of projects, as described in the Parliamentary Committees Act 1991. Based on the evidence considered, and pursuant to section 12C of the Parliamentary Committees Act 1991, the Public Works Committee reports to parliament that it recommends the proposed public works.

Mr TRELOAR (Flinders) (11:04): It gives me pleasure to rise today to speak to the Public Works Committee report, the 19^th report, on the Port Lincoln Wastewater Treatment Plant sludge management upgrade—always very topical, particularly in Port Lincoln when the lagoon is filled and the odour wafts across the city. The first one to hear about it is the local member, so I am pleased that this report has been tabled and the work is now going to go ahead.

The Port Lincoln Wastewater Treatment Plant is located at Billy Lights Point and was first commissioned in 1994. The treatment process consists of a screen and grit removal facility followed by two aeration basins operated as an activated sludge intermittent decant extended aeration (IDEA) process, discharging into sludge and polishing lagoons.

Treated effluent from the wastewater treatment plant is either reclaimed by the Port Lincoln city council's tertiary treatment system or discharged to the ocean via an outfall. Waste sludge from the IDEA tanks is stored and stabilised in four sludge lagoons before being periodically dewatered and used for beneficial agricultural purposes.

The growth in the Port Lincoln catchment, which the Chairman also mentioned in his report, has led to an increase in load to the sludge treatment process at the Port Lincoln Wastewater Treatment Plant. This has meant that the lagoons are approaching capacity and are at times overloaded, resulting in a number of odour incidents being recorded in recent years. In addition, seepage incidents from the sludge lagoon onto the adjacent beach have also occurred in the past due to the lagoon's deteriorating condition.

As a result of these environmental incidents—odour and seepage in 2013 and earlier incidents in the late 1990s—the EPA reviewed SA Water's operating licence and conducted a risk prioritisation review. This determined to include an EIP annexure to the Port Lincoln Wastewater Treatment Plant licence in 2014. This EIP directed SA Water to prevent leakage and uncontrolled overflows from any sludge lagoon and ensure that odour does not exceed six odour units at the nearest residential boundary. I am not going to speculate on what one odour unit is, let alone six; we can only imagine.

The EPA approved SA Water's request to defer its compliance with the EIP until 2020 on the basis that an efficient and prudent solution could be developed whilst mitigating any immediate risk of wastewater odour to the Port Lincoln community or seepage of sludge to the nearby beach.

The objective of the proposed works is to upgrade the existing wastewater sludge management system at the Port Lincoln Wastewater Treatment Plant. This involves implementation of an anaerobic digester/sludge stabilisation system to:

meet the requirements of the EIP to ensure that leakage of uncontrolled overflows from the sludge lagoons are prevented, and that wastewater odour does not exceed six odour units at the nearest residential boundary;

accommodate current and future growth—that is, over the next 30 years—for residential and industrial communities, including the seafood industry. I might add that we all know very well that Port Lincoln is primarily a fishing town and that a lot of the fish are processed in the industrial area of Port Lincoln, which is a good thing to occur. The wastewater treatment plant needs to be able to accommodate the outflow from the fish processing plants but also be mindful of the fact that some of that water is quite saline in nature and so has to be ameliorated; and

the current proposal also needs to improve operability and maintainability of the wastewater treatment plant, including the accommodation of transported waste.

The project is in response to the need for necessary upgrades, as we have said, due to the increase in load to the sludge treatment process at the wastewater treatment plant. This has meant that the lagoons are approaching capacity and are at times overloaded.

SA Water was presented with a number of options, and option A was the preferred option decided upon. This particular option involves the replacement of the sludge lagoons with the sludge thickening anaerobic digestion and mechanical dewatering processes, as well as on-site storage, which is compliant with EPA standards, plus the remediation of one existing lagoon.

Option A also had the fourth lowest NPV at OE stage but was the most preferred option as per the MCA outcome, with minimum risk to SA Water while still ensuring that the requirements of the EIP are met. This option also had a significantly smaller footprint, allowing more room for future expansion if needed; if the Port Lincoln and the seafood industry continue to grow, then that is a very real possibility. It also presents the opportunity to add co-digestion and cogeneration in the future. There are no major business risks and operational risks identified in the preferred option.

In July 2017, option A was endorsed by SA Water's executive steering committee. The scope has not changed since that option was endorsed. However, further investigations followed by the dual early contractor involvement process resulted in refinement of the project requirements, mitigation of some risks and a competitive design and construction total out-turn cost. This resulted in an overall reduction in the capital cost by 14 per cent, from $21.9 million to $18.79 million, which, as I understand it, remains as the final cost.

Congratulations to the committee on good work, and congratulations to SA Water on finally progressing to this project. The fish processors and the residents of Port Lincoln will be only too pleased to get those odour units down.

Mr PATTERSON (Morphett) (11:11): I will just add a little to the 19^th report of the parliamentary Public Works Committee around the efficacy of the application of South Australian funds to this project, which has been outlined by both the member for Kavel and the member for Flinders, that is, the Port Lincoln Wastewater Treatment Plant sludge management upgrade. While this is quite technical in nature, it is certainly required by the good people of Port Lincoln for their needs.

The Port Lincoln Wastewater Treatment Plant is currently located at Billy Lights Point and was commissioned in 1994. Treatment at present consists of a screen grip removal facility, followed by two aeration basins operated as an activated sludge decanting extended aeration process, which then discharges into some sludge lagoons. The treated effluent can then either be reclaimed, and this is done by the City of Port Lincoln council's tertiary treatment system, or discharged to the ocean via an outfall.

The waste sludge from these decanted aeration tanks is stored and stabilised in some sludge lagoons, which are based in the same region as the wastewater treatment plant footprint. They are periodically dewatered, and then the remaining sludge is used for agricultural purposes. One of the reasons for driving this upgrade, the committee was informed, is that the growth in the Port Lincoln catchment has led to an increased load to this sludge treatment process.

Part of that is population, and the committee looked at population growth; it was one factor, but by no means was it the only factor. As the member for Flinders said, there are other issues at play, and one is the increased seafood manufacturing that goes on in Port Lincoln. To try to support the local economy there is obviously a key driver, and an upgraded wastewater treatment plant can be used to increase the processing and provide an economic impact to the area.

Another consideration of this potentially is seepage from these lagoons. We talked about the lagoons being there to be part of the stabilising of the waste afterwards, and it certainly has become an issue from an EPA point of view. There were some other factors, such as odour as well. In 2013, there were some odour and seepage incidents, along with some other incidents in the 1990s, and because of this the Environment Protection Authority reviewed SA Water's operating licence at this site and conducted a risk review.

As a result, it determined that there would be an annexure to the Port Lincoln Wastewater Treatment Plant's licence in 2014, and this directed SA Water to look to prevent leakage and uncontrolled overflows from the sludge lagoon and also to ensure that odour loss does not exceed six odour units at the nearest residential boundary. It is separated from most residences. It is not as though it is right in the middle of Port Lincoln. There are not a lot of residences but it still is something that needs to be looked at by the wastewater treatment plant.

The current proposal looks to meet the requirements of this annexure that I mentioned before, the EIP, to ensure the leakage of uncontrolled overflows from the sludge lagoons is prevented and that wastewater odour does not exceed these six odour units. It also looks to accommodate current and future growth projected over a 30-year period for residential, which I mentioned before, and also the industrial community, which includes the seafood industry. It is also to improve the operability and maintenance of the wastewater treatment plant, including the accommodation of transport of waste. That is an issue, so the more it can be treated on site and looked after, the less you need to have this transported via trucks on the roads.

I will move now to some of the cases. There were quite a number of cases put forward. The base case was to continue business as usual with the continued use of these existing sludge dewatering lagoons. In evidence, we spoke to some of the witnesses about whether the life of the plant could be extended as is. I suppose the directive from the EPA necessitated that that would not be the case.

Other options included option A, which is thickening anaerobic digestion, and dewatering and on-site storage, as well as air-drying from the local farm. That was the preferred option as well. It involves the replacement of the sludge lagoons with sludge thickening anaerobic digestion and mechanical dewatering processes, as well as on-site storage plus remediation of one of the existing lagoons. The committee was taken through as part of the evidence to see what that looks like. It is quite a mechanical, sophisticated process and it certainly is the preferred option, principally around the anaerobic digestion and dewatering.

Another option was a modified version of that where it looked effectively at implementing the thickening and dewatering and on-site storage, as well as the air-drying, for local farm biosolids but then deferring the anaerobic digestion until the next regulatory business period. That effectively produces the same result, but it would be the anaerobic side of it that would be deferred. It was suggested that the unstabilised dewatered sludge would in turn then have to be transported, as opposed to treated on site, and this would be transported to Dublin, which is approximately 600 kilometres from Port Lincoln, quite close to Glenelg—Glenelg?—which is obviously not very important to me! I should say Adelaide. Glenelg is the centre of South Australia, or the capital. But I digress.

This option of transporting it via trucks has high work health and safety risks as well as very real community impact risks from potential road traffic and spillage accidents. Other options were the thickening and aerobic digestions, as opposed to anaerobic, still with the on-site storage and air-drying, but it was put to the committee and SA Water that the anaerobic is a better form of treating the waste.

Two other options were looked at as well, which included implementing the thickening, dewatering and on-site storage but deferring the aerobic digestion. It was similar to option C but, again, with the deferral. The final option was to rehabilitate the sludge lagoons but to operate them at a reduced capacity with the excess unstabilised sludge then transported offsite to Peats Soil in Dublin for composting and re-use. Again, this would involve a lot of transportation of waste which, again, was thought to have too many community risks.

As I mentioned, the deferral of the anaerobic digestion in option B or the aerobic digestion in option D would require renegotiation of the current EIP with the Environment Protection Authority, so again we discounted it. After explaining those options, we came to the conclusion that option A was what SA Water endorsed and put to the committee. It was duly accepted and seen as the way forward in terms of the project itself.

In consideration of that, the committee decided to proceed with option A and recommended that this report be accepted. Oral and written evidence was given to the committee, and the committee is satisfied this proposal has been subjected to the appropriate agency consultation. Based on this evidence, the Public Works Committee reports to parliament, as we do here, that it recommends the proposed public works.

Mr CREGAN (Kavel) (11:20): I thank members of the committee for their assistance in bringing forward the report and also our committee staff for their diligence and hard work in ensuring that we have all the evidence available to us at the time we require it. The member for Flinders, closely familiar with his own community and an advocate for upgrades as needed for residential development and also for industry, has added greatly to the debate. I listened carefully to his commentary and I appreciate it. I appreciate also his guidance in relation to matters that concern his community.

The member for Morphett, of course an engineer by training, brings great skill and expertise to our committee. We depend at times on his advice. I am grateful that he is the deputy chair of the committee and able to bring the type of insight on occasion that lawyers could never bring, so I am personally grateful to him for that. He did make mention that Glenelg and its surrounds might otherwise have been picked as the capital of the state. It is a controversial statement, one I am sure we will debate at length; not now, though, member for Morphett, although I would otherwise take up that opportunity.

Without The Buffalo, of course, the member for Morphett could not lay claim to it being a centre all and perhaps Adelaide would not be here, so in a circular way, member for Morphett, I see your reasoning. It is perhaps more circular than an engineer would otherwise entertain, but nevertheless I see the point and I see what you are thrusting at. It certainly is a matter of some interest to me, a matter I have now reflected on in the presence of us all.

I indicate that I am very grateful for the assistance of our committee staff; they are diligent and hardworking. I also appreciate the evidence that came before us from SA Water. I appreciate that much of the work that has been undertaken is directed at controlling odour leakage from the site. The new lagoons will of course contain much of the waste on the site in ways that are technically appropriate, and those matters are set out in the report. We commend the report to the house.

Motion carried.