Sadler, Mary

Ms. Sadler is an Associate Vice President with Hazen and Sawyer in Raleigh, North Carolina. She has 25 years of experience in the municipal water and...

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About Sadler, Mary

Ms. Sadler is an Associate Vice President with Hazen and Sawyer in Raleigh, North Carolina. She has 25 years of experience in the municipal water and wastewater treatment industry. Ms. Sadler received her Master's Degree in Environmental Engineering from Virginia Tech in 1998 and her Bachelors of Civil Engineering from Virginia Tech in 1997. She specializes in regulatory strategy development, master planning, municipal wastewater treatment design, and water resources planning. Her regulatory experience includes pretreatment, NPDES compliance, environmental documentation, and site-specific water quality studies related to NPDES permit compliance.

Sadler, Mary

Titles from this speaker

Challenges of Leveraging Pretreatment Programs for Advanced Water Treatment and Direct Potable Reuse

Abstract

The National Pretreatment Program implements Clean Water Act (CWA) requirements to control pollutants of concern (POCs) discharged to publicly owned treatment works (POTWs). EPA promulgated 40 CFR 403 to regulate industrial discharges to collection and treatment systems. A POC is defined as any pollutant reasonably anticipated to be discharged in sufficient amounts to interfere with a treatment and collection system. Regulating industry can be a significant challenge for utilities. Even with strong technical justification for a pollutant limit, limits can be challenged by industry on the economics of implementing pretreatment as well as the technical basis. The political issues associated with changing a local limit can create havoc if an industry decides to apply political pressure. The protection of public health and safety is a key concern for direct potable reuse (DPR) systems. The control of pollutants entering the system provides a critical level of protection upstream of advanced treatment. In a DPR scenario, regulatory compliance includes the quality of finished water from an advanced treatment facility. However, the quality of finished water from a DPR system does not readily translate to existing pretreatment programs. In the universe of chemical possibilities, the regulatory bandwidth for implementing water quality criteria or establishing criteria for a maximum load into a sewershed may be impractical given the magnitude of potential chemical risks. The pressures on water supply in the United States is shifting the perspective on the availability and treatability of water for potable use. POTWs are starting to think about how to leverage pretreatment regulations for DPR systems. Table 1 summarizes the various standard methods for implementing local limits. The methods range from direct prohibition to various options of pollutant allocation. Four case studies will be presented highlighting the challenges POTWs have faced with implementing local limits for new and existing industries, as follows: City of Chandler, Arizona: The City has experienced service area changes over the last decade, including substantial increases in industrial flow discharged to the City's sewer system. A One Water cycle is inherent in the City's water supply and treatment infrastructure. The City injects effluent into groundwater for recharge via an Aquifer Protection Permit. Reclaimed water use also provides a significant contribution to the City's effluent disposal portfolio. The City withdrawals groundwater for water supply. This case study will discuss the City's infrastructure relative to the development of an innovative local limits framework that binned industry by size, complexity, and considers the City's water cycle. An extensive sampling plan was developed, to include PFAS, to support the new local limits structure. City of Cartersville, Georgia: The City of Cartersville has actively promoted economic development, which has resulted in new industries locating to the area. The City has water supply availability and local limits that were not viewed as overly restrictive. The new industry is considered 'green' (e.g., electric battery and solar cell manufacturing). These industrial discharges are characterized by pollutants that are 1) not currently included in the City's local limits but are anticipated to cause passthrough and/or interference, or 2) emerging pollutants that are not currently regulated by EPA with established water quality criteria. This case study highlights an example of a utility faced with developing local limits for emerging pollutants from new industrial sources and managing the industrial response without a DPR option on the horizon. Plant City, Florida: Plant City faces significant water quality challenges with where to discharge wastewater effluent for expanded capacity. Surface water discharges are prohibited, and non-potable reuse options have been fully leveraged. Approximately 20% of the City's wastewater is from industrial users. Facing water supply challenges, Plant City developed a framework for an enhanced source control program as efforts are progressing on design of an advanced water treatment facility. City of Burlington, North Carolina: The City of Burlington is located in the Cape Fear River basin where the presence of PFAS has been widely documented. Environmental groups have expressed concern over unregulated discharges of PFAS in wastewater effluent. The City implemented a monitoring program to identify sources of PFAS from the industrial contribution and domestic sources. The City has worked with their industries to reduce the sources of PFAS in the system. These case study perspectives will compare and contrast how utilities are leveraging their pretreatment programs to manage various scenarios and the associated political and economic challenges. The regulatory authority contained in 40 CFR 403 does not directly translate into a holistic mechanism for source control. This paper will provide a perspective on how utilities have responded to industrial issues and the gaps that need to be identified for successful enhanced source control in DPR applications. Additionally, this paper will discuss the common elements of various source control frameworks, including source identification, risk assessment, local limits approaches, monitoring, strengthening enforcement response plans, and public engagement.

EPA promulgated 40 CFR 403 to regulate industrial discharges to collection and treatment systems. Regulating industry can be a significant challenge for utilities. Limits can be challenged by industry on the economics of implementing pretreatment even with technical justification for a limit. The protection of public health is a key concern for direct potable reuse systems. The control of pollutants entering the system requires a critical level of protection upstream of advanced treatment.

SpeakerSadler, Mary

Presentation time

15:30:00

15:50:00

Session time

15:30:00

17:00:00

SessionShaping the Future of Potable Reuse

Session number233

Session locationRoom 340

TopicIntermediate Level, One Water Management, Sustainability and Climate Change, Water Reuse and Reclamation

Author(s)

Sadler, Mary, Walker, Troy, Ishii, Stephanie

Author(s)M.E. Sadler1, T. Walker2, S.K. Ishii3

Author affiliation(s)1Hazen and Sawyer, NC, 2Hazen and Sawyer, AZ, 3, FL

SourceProceedings of the Water Environment Federation

Document typeConference Paper

PublisherWater Environment Federation

Print publication date Oct 2024

DOI10.2175/193864718825159702

Volume / Issue

Content sourceWEFTEC

Word count14

Base text size -

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