The qldwater Consortium for Research and Advocacy on Contaminants is a partnership among Queensland Service Providers to share information and partner with national research & policy programs on contaminants of emerging concern. QCRAC is overseen by the Consortium Steering Group (CSG).
Contaminants of emerging concern are an increasing issue for the local government water sector as community and regulator expectations increase and the ability to detect trace chemicals improves. Costs of dealing with contaminant issues will increase but can be mitigated through joint action and collaboration in national and international initiatives for research, policy and advocacy. In 2019, the qldwater Sewage and Water Environmental Advisory Panel recommended the formation of a Consortium to influence state and national policy, research and communications to lead future discussions about contaminants affecting Queensland Water and Sewerage Service Providers.
Release Date: 27-Feb-2020
The initial value proposition that was provided to invite members to join the Consortium.
On 26 August WSAA hosted a webinar on the topic of Environmental risk assessment for emerging contaminants in sewage in Victoria, jointly presented by Nick O’Connor (Ecos Environmental Consulting) and Daryl Stevens (Atura).
The context was set by James Cleaver (VicWater), who outlined the legislative changes that are taking place in Victoria, moving away from individual prescriptive licence limits to management under a general environmental duty, whereby WSPs are required to demonstrate how they are not causing harm to the environment.
A licence review initiated by the EPA Victoria required analysis of a very large list of 233 substances at each of their 102 WWTPs. In response to this the Victorian water corporations (all 16) got together to jointly employ an ecological risk assessment approach to meet the requirements.
Each STP in the state was assessed according to:
A catchment risk score (high, medium or low) was assigned to each WWTP based on the proportion of trade waste (more or less than 10%) and the presence/absence of high-risk waste streams such as landfill leachate or chemical manufacturer waste in the influent.
The treatment process at each WWTP was assessed, with 11 unique treatment trains identified across 110 different treatment processes. Treatment-train specific LRVs were calculated for each priority chemical based on the treatment train’s combined processes such as:
The combination of catchment and treatment process resulted in a total of 22 separate categories of treatment plants.
The risk posed by each of the 233 pollutants of concern was assessed according to a Weight of Evidence Ranking Tool (WERT). For each chemical the WERT examined: Likelihood, made up of a:
and Consequence, made up of an:
Essentially the WERT assesses indicative risk on an individual substance-by-substance basis by considering, the likelihood of the pollutant of concern being present in the source water, the fate of the pollutant of concern passing through the treatment train into the effluent/biosolids, and the potential harm of the pollutant to receptors.
The WERT risk score output linked the substance-specific risk scores to each of 22 combinations of WWTP & catchment risk, resulting in a spreadsheet matrix that was supplied to the water corporations. The ranking was used to suggest monitoring for those substances with risk score ≥9 (extreme risk), or larger list of substances with score ≥8 (extreme and high risk) for each catchment and treatment train combination.
By approaching the problem as a group, the project provided the following outcomes.
The method permitted a tailored risk assessment to be produced for each WWTP in the state that included monitoring recommendations which if followed, are likely to provide appropriate demonstration of due diligence under new General Environmental Duty legislation.
The presentation and video recording are available through the WSAA website.
Andrew Mitchell, Practice lead for PFAS Investigation and Management at RPS presented at a Webinar to the WSAA Wastewater Source Management Network on 24 July 2020.
The webinar began with some background on PFAS. While the class of compounds include PFOS, PFOA, PFHxS, there is an abundance of so-called “precursor” chemicals which can break down in the environment or in chemical processes to produce the more typical PFAS compounds. Unfortunately, these compounds are not regulated, and manufacturers have taken advantage of this to replace conventional (regulated) PFAS with these compounds which have similar properties.
However, the news is not all bad. PFAS use in Australia has been declining, although its use has not been legislated. Recent analysis shows that concentrations of PFAS in blood serum in Australia are falling (Toms et al. 2019), particularly for PFOS and PFOA which is purported to be a result of the banning of PFAS internationally. This is accompanied by ever-improving analytical methods to measure a greater range of PFAS compounds at lower detection limits.
Recent work on sewage suggests that monitoring may be used to assist with catchment source control. Coggan et al. (2020) provided a benchmarking dataset for PFAS in influent, effluent and recycled water from 19 Australian wastewater treatment plants. Comparison of the three streams (“total PFAS”) provides insights. For example, one WWTP has relatively high levels of PFAS in its influent and effluent, which is likely the result of its catchment area being “highly industrialised” resulting in PFAS discharges to sewer.
Another of the WWTPs has effluent PFAS concentrations that are at least three times that of the influent concentrations. This suggests that the WWTP in question has an issue with precursor chemicals in its catchment. Detailed analysis of the PFAS indicated that precursors are very common in WWTP influent with the result that several classes of PFAS are present at more than 2 times higher concentrations in the effluent as a result of the treatment processes. This information could help target potential catchment sources. Comparison of data provided to qldwater through the SWEAP group for Queensland WWTPs shows similar influent and effluent concentrations to Coggan’s dataset, and consistently higher (“total”) PFAS in the effluent in line with Coggan’s findings.
Similarly, biosolids from seven of 12 WWTPs across Australia contained sulfonamides (which break down into PFAS) while PFOS was present all 12 (Sleep and Juhasz, 2020). Analysis of the data showed no relationship between concentration and catchment, which suggests that point sources (likely industrial) are the dominant contributor to PFAS in the wastewater. Interestingly around 50% of the PFAS in biosolids is PFOS, whereas in effluent it is typically less than 10%. This suggests that PFOS preferentially partitions into biosolids.
TOP assay was conducted on three biosolids samples to assess the impact of oxidative transformation on the levels of PFAS: it was found that total PFAS increased by up to 23%. It is suspected that the high organic carbon content in biosolids limits the oxidation of precursors to PFAS under ambient conditions, which suggests that the TOP assay might represent a worst-case scenario for PFAS content.
PFAS in biosolids for land application is only regulated within Australia in Queensland (under the end-of-waste code). The limits (“trigger values”) are extremely conservative, with the result that PFOS compounds, which are strongly held by soils, may well restrict application of biosolids to only once in any single location.
The recently released NEMP 2.0 is the main tool for management of PFAS in Australia. It has no guidelines that are directly applicable to WWTPs but includes a suggested PFAS Management Framework for WWTP operators. To meet the requirements, which take a conservative approach to PFAS management, WWTP operators would need to complete a characterization of PFAS for their WWTP.
The principal requirements would require a significant investment to achieve:
Characterization must take account of temporal changes in PFAS content, which is subject to diurnal variation, and periodic or one-off discharges of PFAS contaminated materials into the wastewater system. For this reason, averaging or sampling methods that integrate contaminants over time are indicated. Passive sampler technologies are being developed, but they are unlikely to be applicable to wastewater.
A key recommendation from the webinar presentation was the need to control PFAS before discharge to sewers. Identification of the PFAS sources should include both domestic and industrial sources including historical and contaminated sites. A well-known point source to sewers is industrial laundries where the wash water from laundering commercial fabrics, which tend to have surface coatings, is a significant source of PFAS.
Landfill sites are potential point sources due to historical disposal of PFAS containing materials. It is preferable to discharge landfill leachate to a sewer than to the environment, but in doing so it may be the PFAS source that impacts a whole WWTP discharge, and as a result of the partitioning of PFAS into biosolids may mean that the biosolids exceed limits for application. It is technically easier to remove PFAS from clean water than from wastewater, which means that the cost of the cleanup will be less if it is handled at the source than by the WWTP.
The next iteration, NEMP 3.0, is already in preparation, with biosolids criteria to be developed in the next 12 months. Reportedly, the NEMP revision will consider the consequential effects of regulation, which we can hope will include the cost to the community of increased testing and treatment at WWTPs.
On Wednesday 6 May, the Australasian Land & Groundwater Association hosted a webinar on the Queensland EOW Code Biosolids and PFAS Requirements. The two presenters were Isha Sharma and Simone Ventura from the Department of Environment and Science, Queensland.
While we strive for accuracy, the summary has not been reviewed by the presenters and as such any errors or omissions are our own.
The first presentation focussed on the development of the Queensland End of Waste Code for Biosolids which replaced the previous Beneficial Reuse Approvals, which all expired in December 2018. Version 1 of the EOW Code had a limit of 0.39 mg/kg (TOF) for approved use for land application. This value was based on a lower tolerable daily intake than the Australian 2016 enHealth interim reference values, which were determined for drinking water and recreational water, and did not take into account soil quality criteria.
In revising the code, the department reviewed PFAS monitoring data collected from operators, but it was found that the monitoring data was too sparse to be sufficient to develop a limit.
The amended EOW Code Version 2 that came into effect in 1 January this year has a PFAS monitoring requirement with specified trigger values following land application. The DES acknowledges that the research into PFAS monitoring methods and data gathering is ongoing, and as such the requirements that are in place are not final.
Importantly, other options for biosolids management aside from land application, for example co-firing with coal for power generation, require an Environmental Authority for incineration due to the potential for air emission. Furthermore, PFAS monitoring is required for the reuse of the resulting flyash. The current EOW code for coal combustion products is likely to be amended to include a PFAS monitoring requirement.
The second speaker began with a discussion of the issues around the analysis of PFAS in biosolids. The three methods typically referenced are Total Organic Fluorine (TOF), Total Oxidisable Precursor Assay (TOPA) and Standard PFAS analysis. The Standard PFAS analysis measures between 28 and 40 PFAS compounds with fluoridated carbon chains in the range of C4 to C14. The TOPA measures PFAS with chains in the same size range but includes precursor compounds that are oxidisable to PFAS. Finally, TOF measures all PFAS present. As a rule, if all three analyses provide similar results, then there is no evidence for the presence of precursors in the sample. If the TOF and TOPA provide similar values that are greater than the Standard analysis, this suggests that there are some precursors present, but that the TOPA has accounted for them. If the results from the three analyses are substantially different, this suggests that there are precursors present that are not accounted by the TOPA analysis.
Loading rates for application of biosolids are specified in accordance with the NSW Biosolids Guidelines, and must take into account: the suitability of the resource application are; a suitability assessment that includes existing soil nutrient and contaminant levels; and application according to the maximum allowable soil contaminant concentrations (for contaminants other than PFAS). PFAS has post-application soil concentration trigger values in place of a limit.
The PFAS trigger values were determined using impacts on cattle edible products, the most sensitive exposures being milk production, particularly for PFOS contamination. Exposure pathways for PFAS are determined in line with the ANZECC (2000) water quality guidelines for primary industries which consider 20% of the exposure pathway to be dermal, via inhalation or ingestion via drinking water, with the remining 80% by ingestion via accidental soil consumption and through PFAS taken up by plants (i.e. fodder).
All land application of biosolids must be undertaken to ensure that any leachate from the area is not able to migrate to nearby water sources, under the General Environmental Duty of the code.
After the application of the biosolids to land, a sample must be taken as soon as reasonably practicable after the application, but within 3 months, for analysis of a suite of PFAS compounds. If the soil values exceed the trigger values in the code, DES must be notified immediately. The notification will result in a site-specific risk assessment being conducted for the land application area.
Questions following the presentation centred on the actions that DES will take in the event that the trigger values are exceeded. For example, would such land be listed on the Environmental Management Register or the Contaminated Land Register. The DES response was that a risk assessment would be undertaken for the specific site that exceeded the trigger values, and steps would be taken to pre-empt the future contamination of that site.
The Emerging Contaminants Summit 2020 was held on March 10-11, 2020 at Westminster, Colorado. The conference included representatives from universities, research foundations and government agencies to discuss technologies, policy and legal developments.
Unsurprisingly, the main focus of the meeting was on PFAS, although microplastics, BPAs and PPCPs were represented.
There were several presentations of potential interest to Queensland Service Providers:
Innovations in Advanced Oxidation to Control Emerging Contaminants in Wastewater Effluent Karl G. Linden, Professor of Environmental Engineering, University of Colorado Boulder
A Comprehensive Assessment of Contaminants of Emerging Concern Removal and Fate in the Ithaca NY Wastewater Treatment Plant James Gray, Research Chemist, U.S. Geological Survey
Microplastics: Current Regulatory Status and Trends in Risk Assessment Versus Risk Perception Usha Vedagiri, Principal Risk Assessor, Wood
EDC and PPCP Removal from Wastewater: Demonstrated Full Scale Technical Solutions Edward Helmig, Principal Engineer, Woodard & Curran
Distribution of Bisphenol A (BPA) and 5 BPA Analogues in the Solid and Liquid Waste Streams of a Secondary Wastewater Treatment System Bharat Chandramouli, Environmental Scientist, SGS AXYS
Current State of PFAS Analytical Methods Marc Mills, Environmental Engineer, U.S. EPA
PFAS Treatment for Municipal Water Supply: Strategy and Pilot Testing to Restore Groundwater in Orange County, California Megan Plumlee, Director of Research, Orange County Water District
Modelling Bioaccumulation of PFASs in the Aquatic Environment to Support Remedial Decision-Making David Glaser, Principal Scientist, Anchor QEA, LLC
More information about the conference and presentations can be found at the website, although full presentations have not been made available.
An update on some research has recently been published on the state of knowledge around contaminants entering the waters of Great Barrier Reef (GBR) and Torres Strait.
The review study, led by Frederieke Kroon from AIMS, builds on work published through AIMS in 2016. It divides COEC into six categories with a view to assessing the state of knowledge, in particular available monitoring data, about the source and effects of:
The study highlights a lack of available monitoring data on COEC for the GBR, to the point that there was essentially no data at all available on the monitoring of nanomaterials and PFAS in the region, which prevented their inclusion in the study.
WWTPs are considered to be potential point sources of three of the COEC categories: heavy metals and metalloids, marine debris (microplastics) and PPCPs. For PPCPs, land-based WWTPs are viewed as being one of the principal sources to the reef.
The lack of monitoring data for COEC overall means that the potential risk that these compounds pose to GBR ecosystems has not been thoroughly assessed due to a lack of information.
"Hence, an assessment of the ecological risks of priority CECs, including the risks relative to those posed by suspended sediments, nutrients and pesticides is warranted to ensure mitigation efforts are focused on those contaminants posing the highest threat now and into the future."
The authors identified four areas for future research:
This paper highlights some emerging concerns for those operating in the GBR region: from a reef protection point of view we cannot be sure that the contaminants of highest risk to the reef are being addressed, and from an operating point of view we can foresee that there will be drivers for compliance monitoring to increase in the future.
The full review paper is listed on the Research page
In February 2020 the US EPA released an update on its 2019 PFAS Action Plan. The key progress against the plan that is relevant to our industry centres on changes to analytical methods and proposed changes to regulation of PFAS.
1: The EPA has released a new validated testing method for PFAS in drinking water, EPA Method 533. The new Method 533 focuses on PFAS with carbon chain lengths of 4 to 12 ("short chain" PFAS) and complements EPA Method 537.1. Using both methods 29 unique PFAS can be measured in drinking water. EPA Method 537.1 is understood to be widely used in Australian testing laboratories.
2: EPA issued SW-846 Method 8327, a validated method for analysis of PFAS in non-potable groundwater, surface water, and wastewater. It is currently reviewing comment from public consultation to revise the method for publication in the SW-846 (Test Methods for Evaluation Solid Waste) compendium in 2020.
3: In February 2020 EPA announced that it is proposing to regulate both PFOA and PFOS under the US Safe Water Drinking Act (SDWA).
The US EPA has a particular approach to developing future regulation of contaminants under the SDWA. Once every five years a contaminant candidate list (CCL) is developed of no more than 30 contaminants that are required to be monitored nationally by drinking water utilities under the Unregulated Contaminant Monitoring Rule (UCMR). The CCL is made up of contaminants that are currently not subject to regulation, but which are known or expected to occur in drinking water systems and which present the greatest public health concern related to drinking water exposure. Each 5 years the EPA is required to determine whether or not to develop a regulation for at least 5 contaminants on the current CCL.
PFOA and PFOS do not appear on the list for the current UCMR cycle, which came into effect in December 2016. The proposal to regulate PFOA and PFOS is the first step in the process to establish a national primary drinking water regulation for PFOA and PFOS, beginning with a period of 5 years of mandated monitoring in the next UCMR cycle if the proposal is realised.
The US EPA is also conducting an Integrated Risk Information System assessment on a number of PFAS compounds. The assessments will identify the potential human health effects from exposure to each assessed PFAS and will develop toxicity values, as supported by the available evidence. Proposed draft toxicity values of these chemicals for are planned for public and scientific review in 2020.
The full report can be downloaded from the EPA website.
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