Conference Papers

Background Portland Water District (PWD) has four wastewater treatment facilities (WWTFs) with a capacity of more than 25 million gallons per day. Two of the four facilities - East End and Westbrook process most of the solids in the system and were the focus of PWD's comprehensive approach to assess the current solids system and develop a strategic plan that outlines the necessary upgrades, process modifications, and state-of-good-repair projects that PWD should undertake during the next 20-year planning period. PWD began contemplating this planning effort not only due to aging infrastructure, but rather due to increasing concern over lack of biosolids management options and rising public concern around per- and polyfluoroalkyl substances (PFAS) in biosolids. Throughout New England, decreased biosolids management capacity has been a rising concern. Much of the region relies upon landfills and regional incinerators, but beneficial use (land application) has served as a reliable, sustainable option for a number of utilities. In Maine, land application had been an accepted practice, with good market understanding of the benefits of biosolids, including biosolids based compost and thermally dried products. In 2019, however, PFAS contamination was discovered at a Maine dairy farm that had historically land applied both biosolids and short paper fibers. This led the Maine Department of Environmental Protection (DEP) to promulgate soil screening standards for two PFAS - perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). These screening standards were used to limit biosolids land application rates based on the concentrations of these two compounds, and the understanding that PWD might be able to land apply in the future served as an initial assumption of the study. Shortly after study initiation, the Maine legislature passed LD 1911, which prohibits the land application or sale of biosolids and biosolids-derived products in the state of Maine. While options were already limited before this new law, the only option for biosolids management in Maine is now landfill disposal. The passage of LD 1911 thus focused the biosolids master plan on technologies that significantly reduce volume and/or employ thermal destruction. Methodology The goal of this project is to create a 20-year system-wide implementable plan, including near- and long-term improvements that improve the reliability of PWD's solids handling assets while meeting the project goals of mitigating emerging contaminants risks, enhancing reliability and regulatory resiliency, and increasing the public's confidence in PWD's environmental stewardship. PWD worked with its consultant to create a master plan that has both near- and long-term improvements to improve the reliability of PWD's solids handling. Alternatives were evaluated based on regulatory, financial, social, and environmental goals and objectives. An overview of the master planning process is shown in Figure 1. Custom solids and energy models were created to reflect the operation of East End and Westbrook, which were used to determine alternatives for solids handling. The consultant team also provided PWD with estimated operational and capital costs, solids production, and energy requirements based on actual PWD unit costs. Throughout this process, the PWD and consultant team developed and evaluated seven alternatives at six workshops. The outcome of these workshops was a roadmap with several triggers rather than a final solution due to the uncertainty and expected changes in Maine's regulatory framework. Alternatives were evaluated using a mass and energy balance model that supported evaluation of both technical and operational performance. When combined with the capital investment required for each alternative, the model produces a net present cost (NPC) lifecycle cost of each alternative that, when compared to the baseline process condition, determines its financial viability. For this study, it was assumed that the planning horizon for the project would be 20 years. The alternatives evaluated are: -Alternative 0: Status quo. No operational or capital improvements. -Alternative 1: Modified baseline. Baseline operation with new dewatering and sludge storage. This alternative considers the possibility of sending dewatered solids to a merchant facility or to a landfill. -Alternative 2: Thin film Dryer. Westbrook dewatered solids hauled to East End, and the combined solids are dried in a thin film dryer and then disposed of at a landfill. -Alternative 3: PS AD + thermal dryer. Westbrook dewatered solids hauled to East End. East End primary sludge (PS) only mesophilic anaerobic digestion (AD) with thermal drying of all East End and Westbrook sludge. Landfill disposal with possible beneficial end use options in the future. -Alternative 4: Regional Pyrolysis. Westbrook and East End dewatered solids hauled to a PWD-owned regional pyrolysis facility, with either biodrying or thermal drying. Biochar is beneficially used. -Alternative 5: Regional Solar Drying. Westbrook and East End dewatered solids hauled to a PWD-owned regional solar drying facility. Landfill disposal with possible beneficial end use options in the future. Table 1 presents the results of the NPC analysis for these alternatives at a range of solids management costs, which are the largest contributors to the annual solids handling and processing costs. Note: Pyrolysis alternatives do not increase with rising tip fees, as it was assumed PWD had an agreement with the vendor to take the biochar at no cost. Sludge pyrolysis has not been demonstrated at PWD's size, so PWD decided the uncertainty with this technology was too significant at this high capital cost; therefore, PWD decided to continue to monitor the technology before making a final decision. The remaining alternatives were then evaluated based on non-cost factors including de-risking PWD on end use, sustainability, cost predictability, and improved reliability. Table 2 shows a summary of the goal factors for each of the alternatives. The modified baseline, which centers around improved dewatering, was found to be advantageous under current tip fees, and helps de-risk PWD as tip fee volatility increases. This was considered a 'no regrets' project as it both replaces aging infrastructure, and saves PWD money over the long term. With respect to the other alternatives, external factors, particularly the manner in which Maine DEP does or does not permit certain technologies, will affect which alternative should be implemented. As a result, a roadmap was made with key regulatory, market, and other implementation triggers to help guide PWD's actions in the next five years. The roadmap is presented as Figure 2, with the 'no regrets' project serving as the starting point (e.g. will be implemented). Key triggers will cause PWD to go on a certain path of the map, while additional triggers will further refine the likely or viable options. The final two branches (red and orange) of the roadmap are highly unlikely but could still be an outcome. The three key triggers are tip fees continue to rise, landfills reject biosolids, and tip fees stabilize or drop. This adaptable model allows PWD to make immediate improvements that will result in cost savings (dewatering upgrades and thickened sludge storage), while allowing for planning in the face of continuing regulatory flux. It is anticipated that over the next few years, Maine's regulatory approach will stabilize, clarifying the appropriate path forward. Conclusions While state and federal biosolids regulations are still uncertain, PWD can take the following actions recommended by the master plan: -Engage with regional partners now. Should support exist (both from Maine DEP and peer utilities) for regionalization, PWD and its potential partners would have time to determine challenging aspects of partnership such as governance. -Continue to engage with service providers as they explore merchant regional solutions. The master plan established a range of tip fees at which it could be advantageous for PWD to secure long-term management capacity. -Conduct a preliminary design project for the no-regrets projects at East End and Westbrook. This project would provide PWD with a basis of design report (BODR) in which dewatering technology and location would be selected as well as selection of size and location for sludge storage tanks at East End. The BODR would also include evaluation of conveyance of cake, automation of the screw press, and polymer changes at Westbrook. -Continue to engage Maine DEP on technology updates and data updates on PFAS mitigation. -Explore funding mechanisms and continue discussions with vendors on viable solutions. -Visit dryer and other vendor installations.

Access to a safe and reliable water supply is an essential part of ensuring public health and building community resiliency. With continued stress on traditional water sources, and rising exploration of alternative water supplies, water reuse is becoming a larger area of focus in communities. Water reuse, or water recycling, is a proven, science-based process that intentionally captures wastewater, stormwater, saltwater, or graywater and treats it for a designated beneficial freshwater purpose such as drinking, industrial processes, surface or ground water replenishment, and watershed restoration. As the water industry explores recycling water for the purpose of drinking (i.e., potable reuse), communication and public education has been identified as a critical factor in enabling project success. Concerted efforts are being made by utilities and organizations to reach the general public and consumers to communicate the safety of water reuse. Building relationships and a shared knowledge of water reuse processes, risks, and safety between the public health and medical communities and the water sector is key. This session will feature Bart Weiss, a leader in potable reuse in Florida and the nation, to discuss communication and public education around water reuse, particularly as it relates to engaging with medical and public health professionals. The Water Research Foundation Project 13-02 clearly identified the importance of communication plan that includes medical and public health professionals. It is known that community members seek advice on the health of water reuse from their medical professionals and that the public is interested in communication around the safety, quality, and treatment process for direct potable reuse. Building off this knowledge, this presentation will draw from numerous case studies and research around public education, highlighting the importance of engaging public health, health care, and water sector professionals throughout the public outreach process. More broadly, this work will summarize various activities through the WateReuse Association's Public Health and Medical Community Initiative. The University of Texas, Houston School of Public Health and El Paso Water represent one such partnership between public health and water sector professionals. This partnership enabled a greater understanding of how community members respond to various forms of public education. Such findings include the increase in support as residents learn more about potable water reuse (figure 1). Additional partnerships include the College of Public Health at the University of South Florida's collaboration on Florida's Potable Reuse plan and education efforts throughout the state. This partnership builds off the knowledge that the public wants to hear from medical professionals, and in turn enables those medical professionals with key water safety information. Dr. Donna Petersen, Dean of the School of Public Health at the University of South Florida is working with WateReuse members to incorporate presentations on water reuse systems into her curriculum to properly educate Florida residents in anticipation of potable reuse in the state. Expanding these efforts nationwide will be another key to the success of the Public Health and Medical Community Initiative. Partnerships with health professionals are not the only means for the water sector to effectively engage in public education, media outreach such as that with Dr. Sanjay Gupta of CNN visiting El Paso Water to discuss water reuse (figure 2) and recycled water brewing such the New Water Brew Competition can also support a robust communication strategy (figure 3). Allowing the public to hear from established, trusted media sources better enables understanding of the health risks associated with potable reuse without being lost in technical jargon. In a different way, hearing from brewers on the quality recycled water focuses the conversation on the treatment processes and water quality rather than water history. Such projects, coupled with partnerships with health professionals, enable a successful public outreach strategy. This session is aimed at broadcasting key communication techniques and partnerships to better inform participants in their own outreach. Largely, the goal is to open broader conversations of the nexus between public health and water treatment.

The City of Vancouver, British Columbia, is working to develop an integrated or 'one water' approach to delivering water-related infrastructure (i.e., potable, sanitary, and stormwater) to the Cambie Corridor, a rapidly developing transit corridor south of downtown. The current water-related infrastructure is beyond capacity; and a recent land-use plan for the 1,000-hectare corridor revealed that the population living and working there is expected to more than double in the coming decades. These land-use pressures along with climate change and ecosystem health concerns necessitate a fresh, holistic look at all forms of water infrastructure serving the corridor. To create a plan for the corridor, the City used a collaborative engagement process to develop a water-servicing vision and a multi-benefit assessment approach for evaluating one-water opportunities (i.e., programs, policies, and projects). Opportunities include various types of distributed green and blue-green stormwater infrastructure, regional green stormwater management facilities, water conservation and efficiency strategies, site and district scale non-potable water reuse (e.g., rainwater, greywater, and foundation drainage), and policies and programs to mandate, incentivize, and/or encourage private investments and partnerships. The assessment approach, which will be the focus of this presentation, was used to identify, value, screen, and ultimately optimize the suite of opportunities needed to meet the City's objectives. The assessment approach included several analytical tools working in tandem, including (1) a custom-built Water Balance Model paired with a calibrated hydrologic and hydraulic model to evaluate opportunity performance, (2) a GIS tool to help site opportunities, (3) a Decision Support Tool to value ecological and community co-benefits and measures of reliability and feasibility, (4) a scenario planning analysis to account for risks and future uncertainty, and (5) an optimization tool that uses advanced statistical algorithms to identify the ideal combination of opportunities that meets water-servicing targets, minimizes costs, and maximizes co-benefits. This assessment approach allowed the City to balance the trade-offs inherent in a multi-objective analysis in a defensible, transparent, and easy-to-understand way. The effort culminated in development of a high-level long-term water servicing strategy for the corridor and a more detailed short-term capital plan for investments in the next 4 to 8 years.

Facility Overview: South Platte Renew holds the distinction of being the third-largest Water Resource Recovery Facility (WRRF) in the state of Colorado. Serving as a vital lifeline, it caters to the needs of over 300,000 residents and consistently processes an average of 20 million gallons per day (MGD) of wastewater. SPR's asset registry is a testament to its complexity and scale, comprising nearly 6,000 assets across multiple disciplines, encompassing mechanical, electrical, instrumentation and controls, structural, and fleet components. The diversity within this asset portfolio is further underscored by the wide-ranging age of these components, stemming from the original plant construction in the 1970s, complemented by significant upgrades undertaken during the 1990s and the early 2000s. This intricate blend of assets has introduced a formidable challenge for SPR, as it endeavors to strike a balance between the renewal needs of variable aging infrastructure with other process and regulatory capital improvement needs. Asset Management Background: While SPR has been performing certain asset management activities since its original construction, SPR's formal programmatic asset management journey started in 2008 with the acquisition of an Enterprise Asset Management (EAM) system. Since then, SPR has advanced its asset management program by launching a series of initiatives designed to enhance overall asset lifecycle health. These initiatives encompass recurring asset-focused programs, such as equipment rebuilds, tank cleaning, HVAC maintenance, valve exercises, and concrete repair and rehabilitation projects. In addition, SPR has integrated asset management principles into its capital projects through standard development and data utilization. This ongoing commitment to enhancing asset management practices reflects SPR's dedication to continually evolve and improve its approach to ensure the sustained health and efficiency of its vital infrastructure. The Challenge: SPR has diligently worked across various departments to develop data management and maintenance strategies to support the ongoing advancement of its asset management program. However, one thing that became evident to SPR was the lack of a cohesive and organization-wide strategy amid the ongoing tactical endeavors. The lack of understanding and inconsistencies in asset management practices among SPR staff posed a notable challenge. It was not well understood among SPR staff what asset management meant and what the overall goals and objectives of the program were. It was also evident that there were inconsistencies in how asset management practices were being performed. The Solution: To address the challenges faced, SPR embarked on the development of a Strategic Asset Management Plan (SAMP) which had a dual purpose. Firstly, it formalized asset management strategies and policies. Secondly, it actively engaged key stakeholders and nurtured an asset management culture within the organization. The SAMP encompassed critical components such as: Identifying and recruiting key asset management stakeholders across operations, maintenance, engineering, data analysis, and senior leadership staff Developing a clear vision, goals, objectives, and policies around SPR's asset management program Establishing programmatic governance, roles, and responsibilities Defining levels of service and key performance indicators Implementing risk-based renewal planning methodologies in consideration of an asset's condition, criticality, and redundancy Optimizing maintenance strategies Benefits Realized: SPR has already realized several benefits from the development and implementation of the SAMP. There is overall a greater sense of understanding of asset management among staff, there is excitement and the realization of value from asset management activities, and there is consistency and clarification on many procedures and activities. Through the implementation of a SAMP, SPR will also gain an increased resiliency in financial planning through transparent and accurate reporting, as well as operations and maintenance practices, allowing SPR to better maintain high water quality and maximize value to customers. Lessons Learned: SPR's asset management journey offered valuable lessons, including the importance of starting with simplicity and gradually building complexity, eliminating silos, and the foundational importance of thoughtful and strategic data management. The SAMP emerged as a concise, repeatable document that can guide any utility in creating an asset management framework. Key Value Points for UMC Attendees: This presentation by SPR staff and its external consultant will provide attendees with insights into SPR's asset management journey, including: Step-by-step guidance for creating a SAMP and its associated benefits Strategies to avoid single points of failure by sharing institutional knowledge The significance of fostering an asset management culture across an organization Transitioning from fragmented and inconsistent initiatives to a formalized organizational strategy The advantages of self-performing SAMP development in collaboration with external consultants The importance of building upon past successes and discarding outdated approaches to meet current and future programmatic needs. SPR's asset management story serves as a valuable case study, offering practical guidance and inspiration for utilities seeking to enhance their asset management practices.

Introduction and Objectives Our scientific understanding of per- and poly-fluoroalkyl substances (PFAS) in our environment has evolved rapidly in the last several years and PFAS have increasingly gained attention from the public, scientific, and regulatory sectors due to their carcinogenic and reproductive and endocrine disruptive nature. Previous research has illustrated that water resources recovery facilities (WRRF) are notable PFAS emission routes to the environment, both liquid and solid discharge routes. Despite industrial phasing-out of some PFAS and increasing source management of industrial discharges, PFAS are expected to be present in wastewater solids for the foreseeable future. According to Northeast Biosolid and Residual Association (NEBRA), more than seven million dry tons of wastewater solids were produced at WRRFs in 2004 and solids management practices have resulted in the release of approximately 3000 kg PFAS per year to agricultural lands and landfills (Venkatesan and Halden, 2013). Much work has been done to develop and demonstrate wastewater treatment technologies to destroy PFAS compounds (mineralize to non-fluorinated end-products) in wastewater solids, but few studies have documented the practical application of PFAS destruction technologies for wastewater solids or estimated the cost of implementing those technologies. Our team conducted an evaluation for the Minnesota Pollution Control Agency (MPCA) to document the technology options that could be implemented today to remove and destroy PFAS within municipal wastewater effluent, compost contact water, landfill leachate, and municipal wastewater solids. The objectives of this project were to: -establish a framework for determining which technologies meet the definition of commercially available and effective for PFAS destruction -conceptualize upgrades to destroy PFAS at existing WRRFs -estimate the cost of completing these upgrades for a range of WRRF capacities. Systems were conceptualized for facilities ranging from 0.1-10 MGD. For capacity greater than 10 MGD, a regionalized option was considered. This paper will highlight the findings from wastewater solids portion of the study. This information will be valuable for utilities looking to implement PFAS destruction technologies as regulations around PFAS evolve rapidly. Target PFAS Initial work for the study involved selecting a set of PFAS to represent the range of PFAS known or predicted to be in wastewater solids. Selected PFAS are well-described in PFAS treatment literature, frequently detected in wastewater solids, and diverse in chain length and functional groups. Table 1 lists the selected compounds, assumed typical and high concentrations in wastewater biosolids, and associated target post-treatment. The selected PFAS are generally long-chain perfluoroalkyl acids (PFAAs) or are precursors to PFAA formation, which research has shown to partition into solids. Representative concentrations of PFAS were selected from available literature. Technology Screening PFAS destruction technologies were screened for their ability to consistently remove at least one identified PFAS to below the currently accepted laboratory detection limit, as outlined in Table 1. Technologies were further screened by their readiness for full-scale implementation. Wastewater solids PFAS destruction technologies passing the screening included pyrolysis with thermal oxidation of the process gas, gasification with thermal oxidation, and supercritical water oxidation (SCWO). Pyrolysis and gasification systems were considered to use similar enough equipment to be evaluated as a single alternative for conceptual design. Pyrolysis/gasification systems included a thermal dryer as part of the equipment assembly since both technologies require high solids content. Conceptual Design and Cost Estimating A conceptual design was created for both short-listed PFAS destruction alternatives and for solids production rates of 1, 5, and 10 dry tons per day at a given WRRF, corresponding roughly with the plant influent flow rates used for the liquids portion of the study. The feed solids to the pyrolysis/gasification process were assumed to be dewatered to 25 percent total solids. For SCWO, the feed solids were assumed to be screened and dewatered to 15 percent total solids. Construction cost estimates (AACE Class 5) were prepared from recent project estimates and input from vendors. The construction costs were plotted against the system feed rate to create cost curves for each alternative. One example of a cost curve for pyrolysis/gasification is provided as Figure 1. The construction cost curves for pyrolysis/gasification and SCWO, and parameters used to develop each, will be included in the paper. Additionally, a conceptual design for a regional pyrolysis/gasification facility for wastewater solids was developed to represent another approach for utilities. Our findings showed that due to high costs associated with PFAS treatment, regional approach might become viable for smaller facilities (facilities less than 10 MGD). A regional facility would receive dewatered solids from two or more individual WRRFs within a reasonable hauling distance. Fifty dry tons per day was assigned as a representative capacity for a regional PFAS destruction facility. Operation and maintenance costs estimated for recent pyrolysis/gasification projects were assembled to select representative 2022 O&M costs for a 50 dry ton per day facility. A 20-year lifecycle cost analysis was prepared and tested for sensitivity to variations of the tipping fees and interest rates. This paper will include the results and conclusions from the lifecycle cost analysis of the regional facility concept. Conclusion This study documents the cost of implementing currently available technologies to destroy PFAS in wastewater solids. For pyrolysis/gasification, the O&M costs per dry ton trended lower as the system capacity increased, indicating that smaller utilities could reduce costs if they formed a partnership and developed a regional PFAS destruction facility. Demonstration testing of SCWO systems is expected to provide evidence to clarify if similar results can be expected for SCWO systems.

Like many agencies, DC Water is committed to further operationalizing and elevating equity in its capital investments. Some stakeholders have asked for a 'spending per neighborhood' analysis to verify that equity is being considered. While this is an important checkpoint to show the benefits of utility investments throughout the service area, it's also an opportunity to dive deeper. Complex interconnected infrastructure of varying ages and risks requires a more nuanced analysis to provide affordable rates and inter-generational equity in customer experiences, supporting the needs of customers not only in the 20-year planning horizon but over the next 100 years. To support inter-generational equity, DC Water is using an analytical approach in an 'Equity in CIP Planning' tool that goes far beyond a simplistic evaluation of spending per neighborhood to dive into the details of customer experiences, connect those experiences with needed capital investments and operational improvements, and tie the work together with asset management to reduce risks and manage costs equitably and efficiently. DC Water's Equity in CIP Planning tool also creates a two-way communication link between operations customer requests and further engagement opportunities for customers to understand and give input in utility priorities. This paper details the analysis tools and methods DC Water has developed to provide a more in-depth analytical approach for equitable outcomes as well as the outreach and engagement tools for building community trust in the approach. As part of recent Linear Sewer Facilities Plans for Water Distribution and Sewer Collection Systems, DC Water sought to develop a tool to analyze and connect how customer needs relate to investments in the interconnected sewer and water systems. Equitable investments for sewer and water are not as simple as directing resources to a particular vulnerable neighborhood. Sewers serve watersheds and sewersheds, and water infrastructure is connected in pressure zones. Large diameter sewers and water mains as well as treatment facilities, pump stations and green infrastructure serve large areas of customers. Additionally, customers are not static. They may live in one area of the District of Columbia (District) and work or attend school in another area, meaning the customer experience of sewer and water services goes beyond a single service connection. Many investments in the sewer and water systems also benefit customers throughout multiple neighborhoods and wards of the District. How to reflect this complexity in our analysis and engage stakeholders in evaluating the results in a meaningful way is a question worth considering. In support of serving this complex interconnected system, asset management principles integrated into the Equity in CIP Planning tool allow the District to prioritize equitable outcomes while simultaneously supporting efficient investments to reduce risk where the infrastructure needs are highest. A key element is to ensure that customer experiences are sought out and included in Operations data in a way that can be analyzed and systematically included in CIP planning along with data on system condition and risk. This requires quality checking and geo-locating past customer concerns previously recorded in text fields and updating Operations approaches to data gathering for the future to use data more analytically. DC Water identified and is now working to implement a 'sweet spot' of infrastructure rehabilitation level to best support inter-generational equity. This will result in a six-fold increase in capital investments in the linear sewer facilities in the next 10 years, ramping up from approximately $160 Million invested in the last 10 years to over $1 Billion invested in the next 10 years. This increased investment is a catalytical opportunity to engage with stakeholders in relationship and trust-building that DC Water is spending ratepayer dollars in an equitable way to improve their quality of life. In order to further embed equitable infrastructure decision-making into its capital programs and operations, DC Water is focusing on analyzing and identifying potential inequities in customer experiences and evaluating those within the context of social and environmental vulnerabilities. The focus of this work is to protect the needs of the most vulnerable communities from impacts such as flooding and sewage overflows, transportation and daily life disruptions from emergency repairs, and water pressure and water quality that doesn't meet established levels of service. This work supports DC Water's BluePrint 2.0 Strategic Plan imperatives of Equity, Resiliency, and Reliability. DC Water also developed a pilot to provide a scoring 'boost' for local sewer and water rehabilitation and other projects addressing vulnerable customer needs using the Centers for Disease Control and US EPA Environmental Justice Index. As part of a commitment to ongoing learning and adaptive management, DC Water then performed an analysis of the need and benefit of the pilot boost approach for project prioritization on improving customer outcomes and experiences in higher vulnerability communities. By plotting and analyzing key performance metrics such as sewer line breaks and water line breaks per mile in each neighborhood ward and each vulnerability index area, DC Water mathematically evaluated if there are inequities in customer experiences that require using a boost to the prioritization score in certain areas. During the ongoing implementation of the Linear Sewer Facilities Plans for Water Distribution and Sewer Collection Systems, DC Water is using an expanded customer engagement process that utilizes the Equity in CIP tool to tell visual stories that connect between customer experiences and utility investments. The tool brings together Key Performance Indicators and planned capital projects as well as information for customers about how to have problems addressed. The goal is to build trust and two-way communication between customers and the utility so that the intergenerational equity investments meet customer needs and provide community uplift.

Abstract Summary It is well understood that conventional treatment approaches do not effectively remove PFAS from liquids or solids streams at wastewater treatment plants. Future regulatory enforcement of PFAS has varied state-to-state providing uncertainty for utilities as they plan for future process upgrades. To assist utilities and biosolids producers, several biosolids products were tested including dried biosolids, pyrolyzed dried biosolids and composts, all produced with non-industrially impacted biosolids to assess the concentration of PFAS compounds in the finished products and the ability of these processes to reduce and or remove PFAS compounds. The full paper will summarize findings from this study. Introduction Per- and Poly-Fluoroalkyl Substances (PFAS) are a large family of organic compounds, including more than 4,500 synthetic fluorinated organic chemicals used in commercial, consumer and industrial products since the 1940s. Conventional treatment methods do not efficiently remove PFAS which are resilient to degradation and tend to sequester to the treated solids produced and the resultant biosolids. In its most recent (2021) review of pollutants in biosolids, the US EPA identified eight PFAS in biosolids, and is undergoing a problem formulation process which will serve as the basis for determining whether regulation of PFOA and PFOS in biosolids is appropriate. If EPA determines that a regulation is appropriate (currently expected in 2024), biosolids producers will be required to meet certain standards. This potential outcome of EPA's review underscores the importance of understanding technical solutions available to treat PFAS in biosolids if required based on EPA's review process. Technical Content To assist utilities and biosolids producers to understand options available to them to mitigate potential PFAS contamination in biosolids, several biosolids products were tested including dried biosolids, pyrolyzed dried biosolids and composts, all produced with non-industrially impacted biosolids to assess the concentration of PFAS compounds in the finished products and the ability of these processes to reduce and or remove PFAS compounds. Samples of input and output solids, bulking agents and finished products were analyzed for 24 PFAS compounds utilizing Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS). The facilities tested include: three dried biosolids facilities, two pyrolyzed dried products including output solids, gas and oil, and six compost products. Figure 1 provides an overview of PFAS (PFOA, PFOS, and total PFAS) concentrations by sludge type and the impact of composting operations. This figure demonstrates the progression (and conversion) of the PFAS concentration from the various raw sludge types. In some cases, the type of bulking agent used (fresh yard waste, wood chips, or the amount of recycled bulking agent used) can impact the concentrations of various PFAS compounds in the final compost products. Depending on the sludge type, the composting process has shown to increase or decrease measured PFAS. The variability in the results suggest the presence of precursors in the raw sludge. Additional detail regarding these impacts will be provided in the full paper. Figure 2 summarizes reduction of PFAS compounds through thermal drying using a rotary kiln dryer, where a range of 25-75% reduction was observed (45% average reduction) through drying. Figures 3 and 4 summarize the impact of pyrolysis on PFAS degradation in undigested digested and digested sludges, respectively. In both cases, a significant reduction in PFAS compounds was observed through pyrolysis, with near non-detect PFAS concentrations in the biochar and between 85% and over 99% reduction of measurable PFAS was achieved on a mass basis of all outputs including biochar, biooil and pyrogas. This will be one of the first published results on the entire outputs from the pyrolysis of wastewater sludges. Paper and Presentation This paper and presentation will provide information regarding the measured concentrations of PFAS in wastewater solids, dried biosolids, pyrolyzed biosolids (including the resultant pygas) and biosolids based compost products. PFAS precursor analyte presence and concentrations in the input solids as well as the wastewater treatment process used to generate these products will also be presented. This information will be useful for those considering methods to reduce or eliminate PFAS in their own wastewater solids or other input wastewater solids at existing or planned biosolids management operations to ensure the lowest feasible PFAS concentrations in end products can be achieved. This presentation will help utility planners, operators, engineers, and administrators understand the nature of the PFAS issue in biosolids, how these compounds are introduced into biosolids, the rapidly changing regulatory landscape, and what technologies are being used to reduce or eliminate these compounds from wastewater biosolids products.

This paper and presentation provides an overview and analysis of the interesting findings from the WEF MS4 survey, conducted over the past 3 years on a bi-annual basis. The survey has received a statistically significant level of response for each of the three years, and provides valuable insight to the challenges, successes and needs of MS4 stormwater NPDES Permit holders. The paper and presentation will provide an assessment of the data compiled through 2023. The nature of the questions included in the survey paralleled the six identified Stormwater Institute (SWI) objectives to ensure that information received can best enable efforts to meet the WEF SWI future of stormwater vision. Specifically, the survey included the following topic areas: 1.Drivers for MS4 Planning and Investment Decisions 2.Challenges for MS4 Programs 3.Information and Resource Needs for MS4 Programs 4.Preferred Information Sources 5.Annual Program Budgets and Budget Needs Some topic areas in the survey were covered in greater detail than other areas. For instance, the questions addressing item 3 above (Information and Resources Needs for MS4 Programs) covers a majority of the six SWI objectives associated with the Rainfall to Results vision, which requires a significant amount of questions compared with other sections of the survey. Also, it should be noted that the questions under item 5 (Annual Program Budget and Budget Needs) not only provides information on one key SWI objective (Close the Funding Gap), but also supports WEF's ongoing effort to enable the category of stormwater in the American Society of Civil Engineers (ASCE) Infrastructure Report Card©. An important first step in a maturing infrastructure sector is to better understand the fundamental challenges and needs. This survey and analysis represent this first major step in the stormwater sector, which is a field that is notoriously data-poor. By collecting metadata on the sector, this effort places a mirror up to the MS4 sector to identify the priorities that need to be addressed in the near term while allowing for planning for coverage of other areas in a long-term strategic fashion. Results in many areas confirm expectations, such as the strong motivation for investments in stormwater infrastructure associated with regulatory compliance, localized flooding impacts, and the restoration of water quality and habitat, as these are fundamental aspects of many stormwater programs. It is also not surprising that most MS4s (being caretakers of separate storm sewer systems) are not highly motivated by wastewater-oriented runoff-driven impacts. These results suggest a continued focus on regulations impacting the MS4 sector as well as addressing both water quality and quantity issues associated with separate storm sewer systems. A perhaps unexpected finding is the lack of priority noted by respondents regarding climate change dynamics that point to the need to highlight how changing precipitation patterns will impacts MS4s in the future. These education opportunities may be rooted in highlighting the impacts of recent episodic flood events, such as Hurricane Harvey in Houston and the occurrence of two 1000-year-plus storm events in a three period in Ellicott City, Maryland. Future water quality impacts are also evident, as recent studies show that the current approach to stormwater management infrastructure, which has been designed based upon an assumption of climatological stationarity, will become increasingly inadequate to address urban runoff volumes, rates, and associated pollutant loads in the face of climate change. The challenges for MS4s align more closely with expectations, as the survey respondents identified the need for funding, an evolving regulatory landscape, and aging infrastructure as high-priority concerns in stormwater programs. There is a clear thread that ties these topics together, as evolving regulations drive needs to replace aging and failing infrastructure as well as implement additional measures to address continued degradation attributed to runoff that is seen in many urban waters across the U.S. today. And these needs demand higher volumes of funding, which is a challenge in an infrastructure sector where an estimated 1/3 or less of all regulated entities have any dedicated source of revenue, regardless of the level of revenue generated compared with the identified current and anticipated future needs. A positive first step towards addressing the funding challenge is the formation by EPA of a Stormwater Funding Task Force, which is a result of early efforts by the WEF SWI and associated groups to advocate for greater focus in the area of inadequate funding in the MS4 sector. It is clear that continued efforts to address these top challenges are needed.

This presentation is a case study on the use of artificial intelligence (AI) to detect issues and operational problems in sewer systems more quickly and reliably by identifying anomalies in sewer flow data, including: -Sudden shifts indicative of issues such as sensor failure or blockages in the system -More gradual changes in the data over longer periods of time, which point to issues like sensor drift or other less immediately obvious operational or environmental problems -Differences between calibrated hydraulic models and sensor data The authors will discuss the application of our AI based approach for detecting anomalies in a large water/wastewater agency located in the midwestern united states. We have found that our AI based approach is highly effective at detecting subtle anomalies such as sensor drift, as well as sudden shifts in the flow data. In some instances, it has detected issues weeks before they would have otherwise been detected during manual review or inspection. Not only is the solution effective, but we also chose an approach that is relatively easy to understand and explain, which makes it more actionable and less challenging to maintain. Through our presentation, the authors intend to highlight the critical role that engineering subject matter expertise played in the formulation of our successful approach, and demonstrate the success that can be achieved through the nexus of data science and engineering.

Water infrastructure Asset Management (AM) is recognized as a long-game focused on realizing value over the entire life cycle of facilities. This presentation will showcase recent advancements for one utility in leveraging asset management activities to address long-range strategic goals, implement their 'work plan', manage workload and resources, and use simple dashboards to 'move the needle' toward achieving agency goals. King County Wastewater Treatment Division (WTD) provides regional wastewater conveyance and treatment services to 1.9 million people over a 424-square-mile service area in Washington state. WTD's wastewater system includes over $4 billion of conveyance and treatment infrastructure assets. As with most utilities, WTD is challenged by aging assets, including: Treatment and pumping facilities largely built in the 1960s, consisting of over 55,000 pieces of equipment, instruments, and control devices as well as land and buildings. A system of nearly 400 miles of conveyance pipelines, some of which are over 100 years old. Aging infrastructure is a major driver for capital spending and Operations & Maintenance priorities, and WTD has had a formal strategic asset management plan (SAMP) in place for almost 20 years. Updated every five years, the SAMP includes strategies, objectives, and a Work Plan for achieving related goals. WTD updated its SAMP and its Work Plan in early 2019 and implemented an 'Asset Management Work Plan Dashboard' to help guide programmatic activities related to asset management. As with other utilities, WTD faces challenges moving asset management programs toward success, such as: People: Overcoming lack of resources Gaining trust and support from all levels of the organization Breaking down barriers and cultural resistance to change Making everyone feel invested and valued as an integral part of the AM program. Processes: Defining and standardizing business processes Identifying and implementing industry best practices Assessing strengths and weaknesses and leveraging failures as learning opportunities Developing a plan to execute based on findings. Data: Establishing line-of-sight from tactical action plans all the way through to strategic goals and level of service objectives. Creating progress and performance metrics for the asset management program and holding AM and other staff accountable for reaching targets. Transitioning from traditional work planning to data driven prioritizations. 2023 WTD Initiatives Asset management is best accomplished as an enterprise-wide effort that engages resources and business processes from multiple workgroups in an organization. It also produces the best results as a continuous improvement process in making thoughtful and purposeful stepwise competency and performance advancements, as illustrated in Figure 1. As part of the WTD approach, several new initiatives were prioritized in 2023 following the dashboard-based approach. The initiatives are reflective of similar high-priority asset management needs at other utilities, and include: Condition Assessment Key Performance Indicators and Level of Service Reporting Risk Assessment and Replacement Costs Technology Planning and Implementation Spare Parts Management. The presentation will detail how several of these initiatives are being implemented, challenges that are being addressed, and progress to date. Figure 1 King County's continuous improvement process, leveraging the asset management work plan dashboard. Dashboard Management Approach WTD has used a dashboard management approach to guide and manage asset management activities following the release of their 2018 SAMP Update to advance the WTD Asset Management Program. The 2018 SAMP identified over 200 discrete initiatives including near-, medium-, and long-term activities. The dashboard approach has allowed WTD to identify priorities, assign resources, manage task interdependencies, and forecast work products. The presentation will outline how WTD uses and updates the dashboard for the Asset Management Program. Figure 2 The Asset Management Work Plan Dashboard gives asset managers, supervisors, and leadership insight into the performance of the asset management program, and resource needs and availability. Condition Assessment Consistent with work plan priorities, advancing condition assessment programs was identified as a key element for WTD's Asset Management Program. A current focus is to develop a Condition Assessment Manual to coordinate condition assessment programs used by WTD and the workflow and decision-making processes. Specific condition assessment programs WTD relies on include: Critical Asset Condition Assessment oCondition / Performance Monitoring for Target Assets Life Cycle Programs oAge-Based System Replacement for Identified Assets and Systems Engineering Project-Based Condition Assessment oProcess/Facility-Based Comprehensive Team Evaluations Resulting in Project Definitions oCoating / Corrosion Assessment oRoofing Assessment Linear Asset Condition Assessment oVisual Inspection and Criticality Informed The primary feature of the Condition Assessment Manual is a workflow that identifies the data sources, condition rating approaches, and organizational responsibilities related to the various condition assessment programs. Aggregating and prioritizing the results of the coordinated condition assessment programs allows WTD to accurately characterize risk and facility rehabilitation and replacement activities to reduce risk to the utility. The manual also allows WTD to measure and track risk to manage programmatic asset management progress and communicate priorities and progress to the WTD workgroups. The condition assessment initiative also leverages the significant utility effort to implement a new Maximo Computerized Maintenance Management System (CMMS) across the utility. The transition has included substantial technical and logistical challenges, but also provides the opportunity for data management changes. WTD is using this opportunity to look broadly at the data life cycle (Figure 3) and to take full advantage of the benefits of Maximo's new technology capabilities, including tracking condition data in work orders to support decision-making. Figure 3 Leveraging information across the data life cycle The presentation will review the technical and resource requirements for the aggregate condition assessment program and outline data collection, decision-making, and coordination between the various contributing condition assessment efforts. This presentation will allow asset management professionals to gain insights from WTD's successful Strategic Asset Management Plan. The intended audience includes: Utility leadership interested in improving level of service delivery and determining the best way to 'move the needle' through smart allocation of limited resources and competing priorities. Asset Managers looking for innovative ways to advance asset management initiatives and to communicate effectively with leadership and staff. Financial Managers seeking alternative methods for developing financial strategies and plans. Supervisors, operators, and engineers in charge of day-to-day activities that support asset management, looking for ideas on how to overcome common obstacles to implementing key asset management initiatives such as condition assessment. Participants will come away better equipped to develop tactical, actionable initiatives and tasks that will help advance a successful asset management program through a continuous improvement process.

Stormwater design criteria have not been substantially updated since they were first established back in the 1950s. Most stormwater design manuals still reference those same criteria and event rainfall data from the 1961 Technical Paper No. 40, Rainfall Frequency Atlas of the United States. In urban areas we continue to apply these standards without thinking what it means or how it impacts our aging systems. We add on stormwater control measures as required as part of the post construction best management practices of the MS4 permit but those criteria are not integrated into the overall stormwater criteria. The results is an antiquated and outdated set of design standards that do not provide the functional value that the public is paying for. It is even more critical in this time when many cities want to improve the resiliency of urban areas in the face of climate change. However, do we have the criteria and tools to meet this need. Do we have the right design requirements that will result in the stormwater management outcomes that we desire. In Lawrence, Kansas these questions are being asked and evaluated using a city-wide watershed approach. 2D watershed models of all 59 watersheds are being developed to first fully understand the existing conditions and then to apply a range of potential rainfall events to determine what is the most cost-effective solutions. This is not a one size fits all approach but a watershed system approach that looks at what is the most optimal functional value in an area to reduce flooding, improve water quality, and protect public safety and property. This city-wide system multiple benefit approach is then being used to develop design criteria and stormwater management policy that will provide the highest value at the lowest cost. This approach is significantly different than blindly applying an assumed level of service design standard that would result in only larger and larger pipes or large underground storage. Using this approach, the City of Lawrence will develop a set of affordable solutions that will provide the greatest benefit across the watershed to maximize their available budget. This is in contrast to the past approach of designing a project to meet an outdated standard that was costly requiring it to be delayed for several years before it could be built leading to a back log of projects that would never be built. In Westport, Missouri, the oldest part of the City of Kansas City, Missouri, stormwater solutions have been designed to maximize the functional value within an available budget. This design was even more challenging because it was within a combined sewer system. A new design approach was therefore needed to address sever and frequent flooding, meet a federal combined sewer consent decree, and improve the business district. Several past studies had attempted to solve the problem using the old, antiquated design standards that resulted in over designed and unaffordable solutions that could not be built. Meanwhile the area still flooded almost every year impacting business, flooding cars, and causing public health issues given that the flood waters were combined sewer. Something had to change and that required a change in the design standards. Instead of meeting a 10-year level of service requirement the design focused on two recent real rainfall events along with a range of design events from the 2- to 10-year return frequency to establish the highest value solution for the budget. The resulting solution did not eliminate flooding but rather limited the flooding withing the public right of way at a depth and duration that was acceptable. This presentation will provide an overview of the current issues with design standards developed in the 1950s, ideas to improve them, and two case studies that will provide real examples of how and why we need to change. As cities strive to meet sustainability goals stormwater management must also be sustainable in the form of providing for adaptive designs that optimize the functional value at the most affordable price. Furthermore, if we start to consider stormwater as a resource rather than a waste our design objectives change from a drainage design standard to a water resource design standard. How will climate change impact us we really don't know but if we only require more and more conservative design that result in larger and larger pipes, we won't be creating more resilient cities we will only be creating larger uncontrolled conveyance system that impact our downstream neighbors. Resiliency means our design need to meet a range of potential future conditions not just one. Rainfall may get more intense and be of higher volume, but it also may be more time between events. We should be striving to create design standards that consider both outcomes so we can create more sustainable and resilient cities.

Abstract Rising concern of Perfluorinated alkylated substances (PFAS) contamination of our ecosystem has sparked interest in this pollutant as it pertains to water and waste management. While PFAS sources are numerous, it is widely believed that firefighting foam and extensive industrial uses are common pathways for PFAS compounds to proliferate into our ecosystem. In an attempt to better understand the fate and transport of PFAS compounds undergoing supercritical water oxidation (SCWO), a one (1) wet ton per day scale SCWO system was employed to study the elimination efficiencies of this process. There is a pressing need to develop and validate advanced treatment technologies that can destroy PFAS in a variety of substrates. In this paper, we report on how three distinct PFAS waste substrates from three different sources were treated using SCWO process. The waste includes lime stabilized sludge from a municipal wastewater resource recovery facility; aqueous film forming foam (AFFF) from a DoD facility; and spent ion exchange resin from a 'pump and treat' water treatment facility. Supercritical water oxidation or SCWO for short, is a physical-thermal process that relies on the unique reactivity and transport properties of water above its critical point of 374 °C and 218 atm. At these conditions, organics are fully soluble in supercritical water, and with the addition of oxygen, all organics rapidly and completely oxidized to form carbon dioxide, clean water, and inorganic salts. The studies examined a variety of PFAS compounds, both targeted and non-targeted, but most specifically focused on PFOA and PFOS. These two compounds are the most studied PFAS compounds, they are highly toxic and most prolific in our ecosystem. SCWO, on average, was able to eliminate 99.95% of PFOA and 99.99% of PFOS across all waste substrates, and greater than 99.9% elimination of all other PFAS compounds combined. Non-targeted PFAS was accounted for using laboratory scale verification tests by employing fluorine mass balance. No hydrogen fluoride was found in the effluent gas, and all the fluorine from the destroyed PFAS was accounted for as fluoride in the effluent water, with no low molecular weight or volatile PFAS compounds in the emission. This paper will cover the pre-treatment, pre-preparation and supercritical water oxidation requirements for the various waste inputs to ensure complete destruction of recalcitrant wastes without producing any undesired byproducts. The studies produced valuable data and design parameters to support design and deployment of SCWO for real world applications. Introduction - Section removed to fit 9,000 character count - Material and Method An AirSCWO 1 system was used for these studies, this system is the smallest in scale, and designed to continuously treat aqueous waste of about 1 m3 or 1 wet ton of sludge at 10-20% dry solids content per day (Figure 2). The system consists of a 25-gallon feed hopper integrated with a homogenization tank with internal recirculation to keep the slurry in suspension. A high-pressure pump transfers the homogenized waste to the SCWO reactor via a heat exchanger, to preheat the incoming slurry. A high-pressure compressor provides air, also preheated using a heat exchanger, followed by a plug flow once through SCWO reactor. Three cooling heat exchangers and depressurizing equipment bring the outputs to near ambient conditions. For treatability studies, a minimum of 5 gallons is required for a representative run, but larger volumes of wastes are needed to simulate real world operating conditions. A typical run lasts about 12-36 hours, during which the process operates at different conditions, until steady state performance is established, at which point samples of all effluents (liquid, gaseous, solids) are collected and analyzed to determine treatment performance, including fate of N, P, organics and key metals. Most operating parameters are monitored in real time while others, such as trace and emerging contaminants are analyzed off-line using grab sampling. Process operating parameters were monitored for energy balances and energy recovery, these data are used to develop detailed modeling for scaled systems. In an effort to demonstrate the efficacy of SCWO for PFAS elimination for varied input slurries, three wastes from three different sources were selected for the studies. The three wastes are (i) municipal wastewater sludge, which was stabilized using lime but contained high concentrations of PFAS; (ii) full strength aqueous film forming foam (AFFF) and (iii) ion exchange (IX) resin from a pump and treat system, which is sequestering PFAS compounds in the adsorption media. These wastes all pose different challenges, for example, the need for AFFF to be diluted, making it calorie poor and requiring cofuel; or IX wastes being generated once every 6 months or so, requiring the waste to be stored and processed over the period between changes. Results The first study was treating PFAS laden lime stabilized sludge, results for which show that greater than 99% conversion of Chemical Oxygen Demand (COD) to energy, and elimination of 99.95% for PFOA and 99.99% for PFOS. Table 1 shows that the removal across all carboxylic acid (PFCAs) compounds was greater than 99.9%, and across all sulfonic acid (PFSA's) compounds was greater than 99.99%. This waste had no detectable precursors and SCWO demonstrated excellent elimination rates for short chained (6 Carbon and less) PFAS compounds. The process achieved greater than 99.99% elimination across other 24 derivatives of PFAS found in the sludge. In this study, PFOS was the predominant compound and constituted 88% of the influent PFAS but only 3% of the effluent concentration. In the second study, the AirSCWOTM process treated AFFF, diluted down to about 30 times. About 25 L of dilute AFFF was processed (Krause, M. et al., 2022), only 9 compounds of the 28 analyzed were detected in the influent. PFOS was reduced over 99.99%, and PFOA nearly complete at 100%. Table 2 shows that the removal across all carboxylic acid (PFCAs) compounds was greater than 99.9%, and across all sulfonic acid (PFSA's) compounds was greater than 99.99%. This waste had detectable precursors and greater than 99.9% removal was achieved. Greater than 99.99% elimination rates were demonstrated for short chained PFAS compounds. Total targeted PFAS elimination was established at 99.99% over the course of the experiment. In this study, PFOS was again the predominant compound, and constituted 72% of the influent PFAS and 45% of the effluent concentration. The third study was a demonstration aiming to process spent ion exchange resin, a waste byproduct of water treatment, specifically targeting PFAS compounds. The results from the study treating IX demonstrated that PFOS was reduced over 98%, and PFOA nearly complete at 100%. Table 3 shows that the removal across all carboxylic acid (PFCAs) compounds was greater than 99.9%, and across all sulfonic acid (PFSA's) compounds was greater than 99%. This waste had detectable precursors and nearly 99% removal was achieved. Greater than 99.9% elimination rates were demonstrated for short chained PFAS compounds . Total targeted PFAS elimination was greater than 99.5% over the course of the experiment. In this study, both PFHXS and PFOS were the predominant compounds, and constituted 71% of the influent PFAS and 90% of the effluent concentration. The reactor residence time within the SCWO reactor ranged between 68 seconds for all the studies. Greater destruction of PFAS can be achieved by extending the reaction time (e.g., to greater than 10 seconds) to the desired log-reduction of specific PFAS compounds, especially in highly concentrated wastes such as aqueous film forming foam and ion exchange. The non-targeted PFAS elimination was verified at laboratory scale at Duke University by employing fluorine mass balance. No hydrogen fluoride was found in the effluent gas, and all the fluorine from the destroyed PFAS was accounted for as fluoride in the effluent water with no low molecular weight or volatile PFAS emission. (Deshusses, M.A., 2020) Summary As the studies demonstrate, supercritical water oxidation using the AirSCWOTM system can be effectively and efficiently utilized to achieve near complete PFAS elimination in various PFAS contaminated substrates, rendering the process outputs - i.e., water and air free of contaminants. Other studies involving aqueous slurries including pharmaceuticals, PFAS concentrates and microplastic have been successfully treated using AirSCWOTM, demonstrating the versatility of the process to treat and eliminate recalcitrant wastes. With full scale units being implemented, these studies offer valuable insights to further optimize the process and achieve even greater performance and cost effectiveness.