1. Biological Nitrate Treatment: Innovations and Challenges
This presentation will focus on a biological nitrate treatment pilot study conducted at a water treatment plant. The study used an innovative denitrification system and nitrogen gas sparging to lower dissolved oxygen concentration, and it sometimes achieved complete denitrification. This discussion will also focus on the challenges of matching the acetic acid feed to a variable influent nitrate concentration and addressing clogging by bacterial flocs. The treatment approach showed promise; however, reactor design enhancements are needed to bring this technology to small systems. Asher Keithley, EPA Office of Research and Development.
2. Arsenic Refresher
This presentation will provide an overview of arsenic chemistry and treatment considerations. Arsenic accumulation in the distribution system and potential release back to the water will also be discussed, based on retrospective data analysis from EPA’s arsenic demonstration program. Simoni Triantafyllidou, EPA Office of Research and Development
3. An Arsenic Case Study in California: Oasis Mobile Home Park
This presentation will provide an overview of EPA Region 9’s enforcement case with Oasis Mobile Home Park for violation of the Arsenic Rule. Key topics will include environmental justice, enforcement, technical conditions, and community and stakeholder engagement. The unique challenges and successes of trying to bring a small public water system back into compliance will also be discussed. Maria Alberty, EPA Region 9