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Biosolids are such a waste in Queensland

By Arron Hieatt, Water and Sewerage Infrastructure, Local Government Association of Queensland.

I listened to an interesting podcast recently called Poop Train by RadiolabIf the title wasn’t intriguing enough, the podcast was possibly the most interesting 20 minutes I’ve spent in quite some time. New York City’s wastewater treatment managers, faced with a city that generates almost 5000 ML of sewage every day (which went untreated into the nearby rivers until 1986) were on the hunt for a way to dispose of biosolids generated by treatment plants. The solution: send it to farmers in Colorado for use as a soil conditioner. Have a listen to the podcast to find out how that became the best solution, and why it didn’t last.

The idea isn’t new, and humans have been doing it pretty much as long as we have existed. However, technology now means that we commonly treat sewage before we release it back into the environment. A consequence of treatment is the production of biosolids; the sludge that is leftover at the end of the wastewater treatment process.

This sludge contains many important nutrients that can be lacking in areas of Australia. A story by the ABC's Landline last year reported that some farmers in New South Wales made their land more drought resistant by applying biosolids to it.

In Queensland, the recovery of biosolids has one of the highest recovery rates of any waste stream. The Department of Environment and Science’s (DES) Recycling and Waste in Queensland 2017 report states that of the 86,288 tonnes of biosolids produced in 2016-17, almost 90% was recovered. This supports regional agriculture as well as providing a viable way for local governments and water utilities to deal with an unavoidable waste. Beyond the environmental merit in moving towards a circular economy, the Australian Government estimated in 2012 that the nutrients in biosolids were worth between $155 to $294 per tonne.That’s about $30 million each year in Queensland.

Creating and maintaining waste recovery schemes in Queensland hasn’t been easy. Six years ago an important discussion was happening in the state; a review by Sinclair Knight Merz (SKM) investigated the beneficial use arrangements for waste. Criticisms suggested the process was onerous, costly and complex. Industry indicated it was potentially easier to dispose of waste to landfills than find ways to reuse it. The review recommended that the process could be improved by incorporating technical advice and being clearer about the point at which a waste becomes a resource.

Following the review, the Queensland Government passed the Environmental Protection and Other Legislation Amendment Act 2014, which replaced the beneficial use approval framework with the end of waste framework. The changes were intended to “…better recognise the value of waste through the development of new markets for recovered waste materials in Queensland”Chapter eight of the Waste Reduction and Recycling Act 2011 now forms the legislative requirements for this process.

With a renewed approach to redirecting waste away from landfills, the creation of end of waste codes began. Each year since, DES has made a call for ideas for end of waste codes that should be developed. While biosolids had a beneficial use arrangement, the legislative changes meant that the general and specific approvals for biosolids expired on 31 December 2018. DES had been planning for the transition, but formally began its process of transitioning to the end of waste framework in early 2018 when it formed a technical advisory panel for biosolids.

The Local Government Association of Queensland (LGAQ), Queensland Urban Utilities, Unitywater, University of Queensland, Australian Water Association, Department of Agriculture and Fisheries, and Arkwood were all represented on the panel. This dedicated panel of experts worked diligently to review the existing arrangements and provide advice to DES on the end of waste code.

Central to the discussions were the same issues raised by the SKM review: at what point should biosolids become a resource? This was a key issue as the implications could mean that activities such as storage, transport, and mixing would be captured by environmental regulations, and in some instances could mean that regulations or conditions would be applied that have not been previously, along with added costs associated with compliance.

The other key issue was how to handle the risk posed by PFAS contamination that has become concerning for some sections of the community. The national concern about this contamination meant it was inevitably going to be a consideration for the panel. Again, deliberate consideration recommended that the industry should move towards reducing contamination levels, but in a way that would still be achievable for those currently supplying and using biosolids.

One point to note is the development of the code was happening concurrently with the development and review of national standards on PFAS/PFOS. Thus, the uncertainty of some aspects of PFAS management at a national level were magnified during the discussion, and alignment between the national standards and the end of waste code was going to be tentative at best.

After receiving the recommendations by the panel, DES published a consultation code at the end of October. The code differed from the advice of the panel, requiring all testing to be completed prior to biosolids being considered a resource – a process that can take up to several months. This was an issue that existed with the beneficial use arrangements, but the end of waste code provided an opportunity to improve it. The other key difference was that levels of ‘acceptable’ Total Organic Fluorine (TOF, a measure that includes PFAS and other related compounds) were so low that most laboratories were unable to confirm their absence and thus acceptable use as a resource.

The reaction to the code has been noteworthy. DES received over 30 submissions, and both the industry and local government have expressed concerns that the code would result in all biosolids being sent to landfill, as well as others that sought even tighter regulation of biosolids. The extra waste going to landfill is especially concerning for councils as biosolids would be subject to the new waste levy that will take effect from 1 July 2019. This would mean costs of more than $10 million from the new levy alone, an underestimate since the figure was based on the dry weight of biosolids.

The irony of an end of waste code that would potentially create significant waste seems obvious. The process also showed that the concerns raised by the SKM review six years ago are still relevant today. Had the change in frameworks simply been just a name change that failed to really address the problems identified in the review?

More importantly, the development of the end of waste code for biosolids highlighted how emerging contaminants like PFAS must be carefully regarded. The approach to managing these contaminants can have far reaching impacts, particularly if standards are taken from one context like drinking water to another such as biosolids. This does not detract from the fact that the potential threat from PFAS contamination requires close examination. DES and the water industry face complex considerations to adequately ensure that biosolids are continued to be beneficially used while adequately protecting Queensland’s environment.

There is a silver lining to this story. On 1 January 2019 DES approved an end of waste code for biosolids that reflected the existing arrangements under the previous general approval. Specific approvals were also extended for 12 months, until the issues can be discussed and resolved. There is recognition by everyone involved that sewage treatment is an essential part of modern life, and that biosolids should be used where appropriate. The LGAQ and other industry members are continuing to work with DES to establish a workable end of waste code that will improve control of contaminants like PFAS while still capturing the value of biosolids and the nutrients they contain.

What has been clear about the end of waste code process is that it is still maturing in Queensland. Not every waste stream fits nicely into the framework. Also, competing agendas driven by concern about emerging contaminants or other topical issues can delay the process. At its core the intentions are solid; finding ways to end waste are not just good ideas but something the public is increasingly demanding. I have been impressed with the passion that those involved have brought to the discussion, which makes me believe that with just a bit more effort we will find a way to continue and improve upon our high recovery of biosolids in Queensland.

This article appeared in the April 2019 edition of Queensland Source.