Kleinfelder was engaged by the Australian Government to undertake investigations, assess risks, and propose remediation options for non-radiological waste materials remaining on Maralinga Tjarutja lands as part of the Maralinga Site Maintenance Project. Agreeing at the outset that a collaborative approach to engagement on all aspects of the project and a deliberate endeavour to empower the Traditional Owners in making decisions about investigations and planned remediation activities on their lands was imperative to the project’s success.

Kleinfelder undertook an iterative and risk-based approach to investigation of the buried and surface waste materials on Maralinga Tjarutja lands. The remediation options assessment undertaken subsequently by Kleinfelder followed procedures set out in Australian Standard AS ISO 18504:2022 Soil Quality – Sustainable Remediation and was also heavily driven by Traditional Owners requirements and preferences.

Noting the history

In the 1950’s-60’s, nine atomic weapons were detonated at Maralinga and Emu Field, an area in the north-western corner of South Australia. Such testing and hundreds of additional smaller experiments involving radioactive materials, resulted in the displacement of Maralinga’s Traditional Owners.

Following the completion of the Maralinga Rehabilitation Project between 1995 and 2000, which was focused on radiological materials, and a subsequent period of monitoring, the test sites were handed back to the Traditional Owners in 2009. However, following the return of the lands, Maralinga Tjarutja raised concerns about risks associated with the non-radiological waste materials contained within over 200 uncontrolled waste areas remaining on their Traditional Lands. Investigations conducted in 2019 concluded that further investigation and remediation activities (for non-radiological waste materials) were required.

Collaborative Approaches

Assessment of methods used in ongoing engagement showed that the Traditional Owners of Maralinga were receptive to context-rich on-site engagement, often in an informal setting, such as on-site walkovers and discussions. As with many community audiences, the use of visual representations of results or involvement in planned activities achieves effective communication and a high level of engagement. Resulting in key learnings:

• adoption of non-intrusive investigation and remediation methodologies within culturally sensitive areas
• inclusion of aesthetic and physical hazards in the risk assessment evaluation to capture Traditional Owner expectations
• establishment of remediation goals and objectives in close collaboration with Traditional Owners
• development of multi-criteria analysis of remediation options that include social opportunities to the Traditional Owners (e.g. employment, infrastructure with lasting benefit)

Kleinfelder is an environmental consultancy firm, with offices in South Australia, Victoria, New South Wales, and Queensland, bringing together curious and dedicated engineering professionals offering a holistic approach to contamination investigation and remediation projects. Robert Kaftan: was the Kleinfelder Project Manager on the project. He is a Certified Environmental Practitioner, with 14 years of experience managing stakeholder concerns across a range of sectors, including as environment manager at Adelaide Airport. Robert is also an IAP2 Certified engagement practitioner and has led engagement activities with residents potentially impacted by site contamination as well as chairing project control groups with Federal and state regulators and health experts.

An interview with Maya Brennan, Environmental Scientist of engineering consulting and project delivery company, Stantec

Q1: Can you share with us what inspired you to get into your profession and the environmental industry?

I grew up in Mullumbimby, a small town in northern NSW. Growing up I loved being outdoors, surrounded by nature and being active. I decided once I left school, I would study Physiotherapy. After realising how much I loved the science aspect of it, I quickly realised that I wanted to be a scientist. My dad is a sustainability teacher, so I have always known a lot about environmental challenges and the impact it can have on nature and our communities. I then decided to transfer my university degree to a Bachelor of Environmental Science at RMIT University and have never looked back!

I graduated in 2021, also majoring in environmental chemistry and geosciences. Shortly after graduating, I was offered an opportunity to join the workforce at Stantec as an Environmental Scientist in the contaminated land and remediation team. It’s been an incredible journey so far, and I have already learnt so much from my peers.

Q2: Can you tell us a bit about what current work you are focused on delivering in your team at Stantec?

Throughout my time in this role, I have worked on a range of preliminary site assessments, detailed site assessments, groundwater hydrogeology, contamination management, monitoring, environmental sampling, and remediation projects. Currently, I am participating in an ongoing monitoring program to assess changes in the nature and extent of per- and poly-fluoroalkyl substances (PFAS) in groundwater, surface water, pore water and sediment across sites in Victoria and the New South Wales Riverina.

Q3: I understand you are passionate about addressing current environmental challenges. As a young professional new to the industry, can you tell us what you think the upcoming generation can offer to the workforce to improve our environment?

When I started working at Stantec, it was very noticeable to me that I thoroughly enjoyed working on projects which focused on mitigating the impact of human activities, protecting, and preserving the natural environment for future generations. I believe what the next generation of professionals will do for the industry is become more creative and innovative in their approach to help solve problems more effectively and efficiently in the assessments performed for contaminated sites. I believe we are in many ways more adaptable to change, and learning to work with advanced technology and trends, which I openly discussed in my presentation at this year’s ecoforum/SustRem.

Q4: What are you most excited about in 2024 at Stantec? Any projects or new technologies you will be delivering on?

As with many industries, advancements in technology have continually reshaped working within the contaminated land sector. I am excited to be at the forefront of understanding how artificial intelligence (AI) tools can help increase workplace efficiency, convenience, and productivity of project delivery to clients.

In my abstract for the Australian Land and Groundwater Association Ecoforum, I talked about how advancements in technology, including the emergence of artificial intelligence tools, have significantly transformed the contaminated land sector. For example, the speed of which AI tools enables immediate response, including the notification of stakeholders and management plans for contaminated locations. This can significantly reduce impact on our environment and human health. Speed and efficiency are everything in our current climate and I look forward to learning more about how our team can continue to apply these advanced applications in our fieldwork in 2024.

Maya Brennan, Stantec

Maya is an environmental scientist specialising in contaminated land investigation and remediation. Her responsibilities have included environmental sampling and monitoring fieldwork, hydrogeological investigation, land rehabilitation, and data analysis. She has worked on a range of preliminary and detailed site investigations and ongoing monitoring programs and developed relevant field and report writing from dealing with a variety of site types and contamination issues.

Maya is passionate about promoting sustainability and environmental action to address current environmental challenges. She enjoys working on projects focused on mitigating the impact of human activities, protecting and preserving the natural environment for future generations. She has recently written an abstract for the Australian Land and Groundwater Association Ecoforum on how advancements in technology, including the emergence of artificial intelligence tools, have significantly transformed the contaminated land sector, improving workplace efficiency and productivity. In addition to exploring her passion for environmental issues, Maya likes to read, exercise, craft, and travel.

Stantec: The Stantec community unites approximately 28,000 employees working in over 400 locations across six continents. We collaborate across disciplines and industries to bring buildings, energy and resource, environmental, and infrastructure projects to life. Our work—engineering surveying, environmental sciences, project management, and project economics, from initial project concept and planning through design, construction, and commissioning—begins at the intersection of community, creativity, and client relationships.

Our local strength, knowledge, and relationships, coupled with our world-class expertise, have allowed us to go anywhere to meet our clients' needs in more creative and personalised ways. With a long-term commitment to the people and places we serve, Stantec has the unique ability to connect to projects on a personal level and advance the quality of life in communities across the globe.

Article Published on 03/11/2023

The statements, analyses, opinions, information and conclusions that may be found in the articles of this publication are those of the author and not of the Australasian Land & Groundwater Association Ltd (ALGA), which only acts in the capacity as publisher. No part of this publication can be regarded as legal advice. Although care has been taken in preparing this publication, neither ALGA nor the author represent or warrant that the information supplied is current, complete or accurate. To the full extent permitted by law, the author and ALGA do not accept any liability, or owe a duty of care, to any person in respect of any such information. No person should rely in any way on the content of this publication and are encouraged to seek independent legal or other professional advice, if required.

What are CFWs?

CFWs mimic the appearance of natural floating islands but are enhanced with the advantages of a wetland system's biological and biogeochemical processes. CFWs provide water treatment functions commonly found in both pond and conventional constructed wetland systems. Unlike a conventional constructed wetland, CFWs use a buoyant structure to support planting of the vegetation, allowing the roots to grow freely into the water body, deriving nutrients from the water in which it is floating. The large surface area of plant roots also provides a habitat for microorganisms (biofilms) which facilitate nutrient removal through phytodepuration and capture of suspended particles within the water source. As they float on the water surface, CFWs can be retrofitted into existing waterbodies without impacting flood storage capacity.

Schematic diagram of a constructed floating wetland (Source[1])

What are the potential applications of CFWs?

Commonly reported benefits of CFWs include their efficacy in removing nutrients (phosphorus and nitrogen-containing compounds) from stormwaters, and wastewaters (industrial and domestic). CFWs can attain removal rates up to 98% for total phosphorous (TP) and greater than 90% for total nitrogen (TN) from diverse water sources[1, 2]. It can also be used for removing heavy metals such as cadmium (Cd), copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni) and zinc (Zn)[3].
In addition to the above treatment benefits, a wide range of investigations have been conducted on the capacities of CFWs for removal of organic compounds present in various waters and wastewaters. These include removal of pharmaceutical and personal care product compounds (PPCPs), pesticides and fire-retardant chemicals.

Our recent research has shown the capability of three hydroponically grown wetland species (Phragmites australis, Baumea articulata and Juncus krausii) to bioaccumulate and translocate two per-and polyfluoroalkyl substances (PFAS), namely perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) [4]. These are commonly found in fire-fighting foams, and have been detected in stormwater. Consequently, these plants could serve as promising candidates for integration into a CFW system.

Percentage removal of PFOS and PFOA by various wetland plant species (Source[4])

There are many reported benefits of CFWs that extend from water treatment for removal of pollutants and water quality improvements. These benefits include enrichment of aquatic biodiversity, wave energy dissipation, landscape amenity enhancement and increased socio-economic value.

What are the key factors influencing the CFW’s performance?

A wide range of pollutant removal rates have been reported for CFWs in the field. The CFWs performance and the ability of nutrients, heavy metals, and organic compounds to accrue and translocate within the plant depend on a range of factors. This includes plant type(s) used, management of the CFW system (e.g., rate of plant growth harvesting), water conditions (temperature, flow rate, turbidity, aerobic, anoxic, anaerobic) and climate. Further, the treatment performance of a CFW highly depends on the hydrodynamic flow conditions around the plant root systems (i.e., the fraction of water in the system that passes through a root zone; and the residence time distribution within those root zones).
Where do we go from here?

One of the challenges in evaluating CFWs is understanding the impact of the technology in terms of treatment efficiencies and reaching defined and expected performance targets. Assessments appear to be often based on quantitative determination of key elements and/or compounds (and derivative compounds) that have accumulated in plant tissues and/or based on experimental configurations by which removal rates from test waters are examined. To date, few studies have been conducted to examine treatment efficiency from a mass balance approach where the key elements and/or compounds are quantified at the inflow of the water body being treated, followed by quantification across different phases of the water body (water, sediment, sludge), and finally evaluating untreated discharges from the water body, i.e., pollutants not removed following the CFW treatment.

Currently, controlled pilot CFWs have been installed in an urban stormwater stream channel at Salisbury, South Australia1 and in a wastewater lagoon at Cowes Wastewater Treatment Plant, Victoria2. These trials will allow us to assess long-term overall performance of the CFW treatment. Seasonal performance variations would be also considered.

1 This project is a joint initiative between Salisbury Water, University of South Australia, Bygen, Clarity Aquatic, Covey Associates and CSIRO with R&D funding from Salisbury Water.

2 This Project is a joint initiative between Westernport Water, Deakin University, Clarity Aquatic, Covey Associates and CSIRO with funding from the Victorian Government, Intelligent Water Networks and Yarra Valley Water.

For more information, feel free to contact Dr. John Awad (john.awad@csiro.au) and Dr. Divina Navarro (divina.navarro@csiro.au) at CSIRO. If you’re coming to the Ecoforum/SustRem 2023, make sure to attend the presentations on CFWs by Dr. John Awad.

References:

[1] J. Ayres, J. Awad, C. Walker, D. Page, J. van Leeuwen, S. Beecham, Constructed Floating Wetlands for the Treatment of Surface Waters and Industrial Wastewaters, in: N. Pachova, P. Velasco, A. Torrens, V. Jegatheesan (Eds.), Regional Perspectives of Nature-based Solutions for Water: Benefits and Challenges, Springer International Publishing, Cham, 2022, pp. 35-66. https://doi.org/10.1007/978-3-031-18412-3_3.
[2] J. Awad, G. Hewa, B.R. Myers, C. Walker, T. Lucke, B. Akyol, X. Duan, Investigation of the potential of native wetland plants for removal of nutrients from synthetic stormwater and domestic wastewater, Ecological Engineering 179 (2022) 106642. https://doi.org/https://doi.org/10.1016/j.ecoleng.2022.106642.
[3] M. Afzal, K. Rehman, G. Shabir, R. Tahseen, A. Ijaz, A.J. Hashmat, H. Brix, Large-scale remediation of oil-contaminated water using floating treatment wetlands, npj Clean Water 2(1) (2019) 3. https://doi.org/10.1038/s41545-018-0025-7.
[4] J. Awad, G. Brunetti, A. Juhasz, M. Williams, D. Navarro, B. Drigo, J. Bougoure, J. Vanderzalm, S. Beecham, Application of native plants in constructed floating wetlands as a passive remediation approach for PFAS-impacted surface water, Journal of Hazardous Materials 429 (2022) 128326. https://doi.org/https://doi.org/10.1016/j.jhazmat.2022.128326.

Figure 1 - Biosolid windrow management as generated by DALL-E AI

Mechanisms for Managing PFAS in Biosolids:

Mitigating PFAS risk in biosolids typically involves three principal approaches: prevention, treatment, and risk management through controlled reuse. Prevention seeks to intercept PFAS before they enter biosolids, while treatment methods attempt to eliminate PFAS from the finished biosolids product either through separation-concentration or direct destruction (Vo et al., 2020; Garg et al. 2023). Risk management emphasizes judicious biosolids reuse practices. Among these, behavioral changes regarding biosolids reuse emerge as an attractive, low-capital-cost solution that hinges on effective management practices that promote reuse in a risk proportionate manner, with lower risk (less contaminated biosolids) used for sensitive uses such as agriculture, and higher risk (likely more contaminated) biosolids used for less sensitive end uses (HEPA 2023) such as landscaping and mine rehabilitation. This is contextual, and managing risk in this manner has its limits, where exceeded, more costly risk mitigation mechanisms such as turning biosolids into biochar, energy or disposal are relied upon.

However, stopping PFAS from getting into biosolids in the first place is naturally bandied as the perfect solution, and in some ways, it is. It solves the PFAS problem not only for biosolids, but also for recycled water and effluent. However, this cannot be achieved simply through banning PFAS. Literature appears to suggest that widespread bans and tighter trade waste restrictions would see the legacy issue of managing PFAS already entering the system from various sources with us for decades (Gallen et al., 2018). Further, a change in the types of species present in biosolids shifting from PFOS, PFOA and PFHxS to shorter chain perfluorocarboxylic acid species (Gallen et al., 2022; Helmer et al., 2022) shown that PFAS challenges will extend well beyond PFOS, PFOA, and PFHxS, which are still present in wastewater globally despite phaseouts.

Logically, the next item that is often raised is the potential to treat influent to prevent PFAS from sorbing to biosolids. This presents several key challenges around the complex influent matrix but may be feasible in some cases based on treatment plant scale. Irrespective of whether reducing inputs to biosolids is achieved by reducing PFAS inputs to influent, or treatment of influent, industry needs to know more about PFAS concentrations in influent and the relevant sources to adequately manage PFAS inputs to WWTPs, and hence into biosolids.

Figure 1 - Biosolid windrow management as generated by DALL-E AI

Deciphering Influent Complexity
An operationalizable understanding of PFAS entry routes into biosolids hinges on characterizing influent sources and their PFAS profiles. Influent, comprising trade waste, domestic sewage, and diverse inputs like stormwater and groundwater, and necessitates detailed analysis for effective management. The composition and distribution of PFAS compounds within influent sources assume pivotal roles in shaping biosolids contamination profiles. Szabo et al. (2023) identified PFAS concentrations in influent ranged not only between PFAS species distribution, where perfluoroalkyl carboxylic acids (PFCAs), disubstituted phosphate esters (diPAPs), and perfluoroalkyl sulfonic acids (PFSAs) contributed weekly mass loads of 37%, 30%, and 17% respectively, but also temporally, with different mean sum PFAS detected on different days across a range of PFAS species over a week long monitoring period. Other studies have quantified the per capita background release of PFAS to WWTPs in Australia, with Nguyen et al. (2022) estimating this to be 8.1–24 μg/d/per person for the 12 PFAS species studied. However, noting the variety of species present in wastewater, this is likely an underestimation of total PFAS mass flux, particularly considering that there is limited data for novel short-chain, ultra-short chain, and PFAS precursor species available globally (O’Connor et al., 2022). This is supported by Gallen et al. (2022), where a change from longer chain PFAS species to short chain perfluorocarboxylic acids was highlighted as a key consideration or the future. Effectively managing PFAS contamination in biosolids demands insights into influent PFAS species and their origins, where questions arise if PFAS detected in biosolids are namely transformation products, those PFAS species in influent that have a higher affinity for sorbing to solids, and whether each of these were originating in trade waste, domestic sewage, or other inputs. Irrespective, the influent PFAS mass flow is a factor of PFAS species distribution based on input sources, their relative concentrations, and the relative volumes of each of these inputs. Developing a better understanding of these will assist in evaluating the efficacy of strategies such as trade waste regulations at reducing PFAS mass flows to WWTPs. Striking a balance is crucial, as high PFAS concentrations in a specific source might not necessarily correlate with high mass flows to biosolids due to the prevalence of species that prefer remaining in solution or undergo transformative processes by biotic or abiotic means (O’Connor et al., 2022).

Effectively, literature is somewhat still exploring this notion, with studies such as Feng et al. (2012) presenting an early position that population-related emissions cannot wholly explain the occurrence and concentrations of PFAS in WWTPs and that higher PFAS influent concentrations are typically observed in WWTPs located in predominantly industrial areas. More recently, Gallen et al. (2022) suggested that on days of industrial input to influent, industrial discharges would represent >50% of average annual loads to WWTPs for eleven studied PFAS. The forensic approach employed by Szabo et al. (2023) detected simultaneous pulse events lasting up to 3 hours for PFOS and PFHpS, and considering these were above the baseline mass flow, indicated significant industrial or commercial waste discharge. An earlier study by Coggan et al. (2019) used principal component analysis to show strong associations between odd chained PFCAs, PFHxA, PFSAs, and 6:2 FTS with daily inflow volume and the proportion of trade waste accepted by WWTPs. This is supported by a much larger meta-analysis conducted later by Cookson and Detwiler (2022), where over 460 influent samples across a variety of international studies found effluents from WWTPs that include a significant industrial component to their influent have higher PFAS concentrations.

Conversely, while Nguyen et al., 2022 acknowledged the number of industrial sites positively correlated with the per capita mass load of Σ12 PFAS (r = 0.5–0.63, p < 0.01), it was posited that this only supplemented the background mass flow with more than half of the PFAS (∼59%) mass attributed to background release (domestic inputs) and the remaining (∼41%) to catchment specific point sources and industry. In a review by O’Connor et al., (2022), it was noted that PFOA, PFOS, PFHxS, PFBA, and PFHxA are the most dominant PFAS compounds found in domestic effluents, however concentration and species distributions varied greatly. Vo et al. (2020) noted a broader range of PFAS detected across studies and estimated a domestic background of total PFAS typically less than 100 ng/L. Moodie et al. (2021) suggested based on a population normalised concentration regardless of WWTP, region or capacity, that the domestic inputs constitute the baseline PFAS loading, estimated at 6 mg PFAS per person per year. Interestingly, the recent work published by Thompson et al. (2023) corroborated some of the findings in Moodie et al. (2021), namely surrounding the dominant DiPAP influent load, and the potential for PFAS mass loads to be largely associated with domestic baseline mass flows. In the study, Thompson et al., 2023 found that PFAS loading into wastewater systems from toilet paper included significant inputs of 6:2 fluorotelomer phosphate diester (6:2 diPAP) and contribute from 6.4 to 80 μg/person-year of 6:2 diPAP to wastewater–water systems.

Overall, while literature characterises PFAS mass flows through WWTP influent, effluent and biosolids, these seldom closely explore a sufficiently broad spectrum of PFAS, precursors, and the variety of inputs that constitute influent. Influent is hard to characterize in this sense, as rigorous sampling programs with careful experimental design are required to assist in disambiguating inputs, by sampling the system based on available information on where inputs are still largely or completely segregated. Often the assumptions in such studies pose significant accuracy and uncertainty limitations. Secondly, an understanding of PFAS partitioning behavior and precursor transformation in the WWTP process is required to understand if the inputs targeted for PFAS mass flow reduction would in fact have the desired effect on reducing biosolids PFAS burdens. Noting that reductions of total PFAS mass might not equate to reduction in PFAS mass loads accumulating in biosolids if they have not removed or reduced the specific PFAS species that accumulate in biosolids. As such, where the prevalence of the accumulating species is associated with a specific input (ie. the domestic baseline mass load), controlling other inputs such as trade waste may be misplaced or ineffective.

Figure 3 - Influent as generated by DALL-E AI

Towards Sustainable Management and Resource Recovery

In the pursuit of heightened resource recovery in alignment with national waste policies, addressing PFAS contamination takes center stage. If we can’t measure it, we can’t manage it, and it is clear that outside of identifying key risks, there is still some work to be done to better understand how we can not only reduce PFAS mass loads reaching WWTPs but target the key inputs that result in PFAS enrichment in biosolids. To do so there is a need to manage those species that partition into biosolids in influent, to manage the risk of the resultant residuals. Ignoring this challenge could compromise waste treatment efficiency, biosolids resource recovery potential, and environmental integrity. A profound grasp of influent sources and PFAS characteristics is imperative to achieve the ambitious goal of 80% resource recovery by 2030, while also managing PFAS risks. Only through a comprehensive understanding of the complex factors that see PFAS accumulating in biosolids can we engineer effective and sustainable PFAS management strategies that would ensure biosolids reuse remains a resilient, environmentally sound practice.

References

Coggan, T. L., Moodie, D., Kolobaric, A., Lee, E., Fernandes, M., Clarke, B. O. (2019). An investigation into per- and polyfluoroalkyl substances (PFAS) in nineteen Australian wastewater treatment plants (WWTPs). Heliyon. https://doi.org/10.1016/j.heliyon.2019.e02316.
Cookson, E. S., Detwiler, R. L. (2022). Global patterns and temporal trends of perfluoroalkyl substances in municipal wastewater: A meta-analysis. Water Research, 221, 118784. https://doi.org/10.1016/j.watres.2022.118784.
Ebrahimi, F., Lewis, A. J., Sales, C. M., Suri, R., McKenzie, E. R. (2021). Linking PFAS partitioning behavior in sewage solids to the solid characteristics, solution chemistry, and treatment processes. Chemosphere, 271, 129530. https://doi.org/10.1016/j.chemosphere.2020.129530.
Gallen, C., Bignert, A., Taucare, G., O'Brien, J., Braeunig, J., Reeks, T., Thompson, J., Mueller, J. F. (2022). Temporal trends of perfluoroalkyl substances in an Australian wastewater treatment plant: A ten-year retrospective investigation. Science of The Total Environment, 804, 150211. https://doi.org/10.1016/j.scitotenv.2021.150211.
Gallen, C., Eaglesham, G., Drage, D., Hue Nguyen, T., Mueller, J. F. (2018). A mass estimate of perfluoroalkyl substance (PFAS) release from Australian wastewater treatment plants. Chemosphere, 208, 975-983. https://doi.org/10.1016/j.chemosphere.2018.06.024.
Garg, A., Shetti, N. P., Basu, S., Nadagouda, M. N., Aminabhavi, T. M. (2023). Treatment technologies for removal of per- and polyfluoroalkyl substances (PFAS) in biosolids. Chemical Engineering Journal, 453(Part 2), 139964. https://doi.org/10.1016/j.cej.2022.139964.
Heads of the EPAs Australia and New Zealand. (2023). Draft PFAS NEMP: 3.0 Supplementary Document (biosolids).
Helmer, R. W., Reeves, D. M., Cassidy, D. P. (2022). Per- and Polyfluorinated Alkyl Substances (PFAS) cycling within Michigan: Contaminated sites, landfills and wastewater treatment plants. Water Research, 210, 117983. https://doi.org/10.1016/j.watres.2021.117983.
Ilieva, Z., Hamza, R. A., Suehring, R. (2023). The significance of fluorinated compound chain length, treatment technology, and influent composition on per- and polyfluoroalkyl substances removal in worldwide wastewater treatment plants. Integr Environ Assess Manag, 1–11. https://doi.org/10.1002/ieam.4778.
Johnson, G. R. (2022). PFAS in soil and groundwater following historical land application of biosolids. Water Research, 211, 118035. https://doi.org/10.1016/j.watres.2021.118035.
Moodie, D., Coggan, T., Berry, K., Kolobaric, A., Fernandes, M., Lee, E., Reichman, S., Nugegoda, D., Clarke, B. O. (2021). Legacy and emerging per- and polyfluoroalkyl substances (PFASs) in Australian biosolids. Chemosphere, 270, 129143. https://doi.org/10.1016/j.chemosphere.2020.129143.
Nguyen, H. T., McLachlan, M. S., Tscharke, B., Thai, P., Braeunig, J., Kaserzon, S., O'Brien, J. W., Mueller, J. F. (2022). Background release and potential point sources of per- and polyfluoroalkyl substances to municipal wastewater treatment plants across Australia. Chemosphere, 293, 133657. https://doi.org/10.1016/j.chemosphere.2022.133657.
O’Connor, J., Bolan, N. S., Kumar, M., Sutradhar Nitai, A., Ahmed, M. B., Bolan, S. S., Vithanage, M., Rinklebe, J., Mukhopadhyay, R., Srivastava, P., Sarkar, B., Bhatnagar, A., Wang, H., Siddique, K. H. M., Kirkham, M. B. (2022). Distribution, transformation and remediation of poly- and per-fluoroalkyl substances (PFAS) in wastewater sources. Process Safety and Environmental Protection, 164, 91-108. https://doi.org/10.1016/j.psep.2022.06.002.
Szabo, D., Marchiandi, J., Samandra, S., Johnston, J. M., Mulder, R. A., Green, M. P., Clarke, B. O. (2023). High-resolution temporal wastewater treatment plant investigation to understand influent mass flux of per- and polyfluoroalkyl substances (PFAS). Journal of Hazardous Materials, 447, 130854. https://doi.org/10.1016/j.jhazmat.2023.130854.
Thompson, J. T., Chen, B., Bowden, J. A., Townsend, T. G. (2023). Per- and Polyfluoroalkyl Substances in Toilet Paper and the Impact on Wastewater Systems. Environmental Science & Technology Letters, 10(3), 234-239. https://doi.org/10.1021/acs.estlett.3c00094.
Vo, H. N. P., Ngo, H. H., Guo, W., Nguyen, T. M. H., Li, J., Liang, H., Deng, L., Chen, Z., Nguyen, T. A. H. (2020). Poly‐and perfluoroalkyl substances in water and wastewater: A comprehensive review from sources to remediation. Journal of Water Process Engineering, 36, 101393. https://doi.org/10.1016/j.jwpe.2020.101393.
Xiao, F., Halbach, T. R., Simcik, M. F., Gulliver, J. S. (2012). Input characterization of perfluoroalkyl substances in wastewater treatment plants: Source discrimination by exploratory data analysis. Water Research, 46(9), 3101-3109. https://doi.org/10.1016/j.watres.2012.03.027.