QUANTIFYING VIRUS REMOVAL BY MANAGED AQUIFER RECHARGE Christina Morrison, Walter Betancourt, Chuck Gerba and Ian Pepper RESEARCH PROGRESS REPORT UA-05-S2018 STATUS: CONTINUING – NO ADDITIONAL FUNDS REQUESTED Relationship to Technology Roadmap: Municipal Water Use Practices and Wastewater Reuse Background: Key Findings: Managed aquifer recharge – soil aquifer treatment is practiced throughout Arizona and Southern California for recycled water Provides additional treatment of recycled water to remove pathogen and trace organics Studies on virus removal have largely been limited to laboratory soil columns Field studies now possible because large volumes (1,000 to 3,000 liters) can be collected and more types of viruses detected California requires a 6-month underground retention No detection at site WR-069B Detection of non-human viruses at site EW-008A Similar log reductions from both sites PMMoV found in highest concentrations in both effluent and groundwater CrAssphage found in groundwater on occasion Generally 4-6 log10 reduction of virus Duration: Objectives: July 1, 2017 – Dec. 31, 2018 To provide a basis for giving “Removal Credits” for virus reduction by MAR for recycled water based on Infiltration rates Depth to groundwater retention time (virus die-off) Type of virus Determine if coliphage and or Pepper Mild Mottle Virus can be used as a monitoring tool for performance Budget Requested: No new funds requested Approach: Select 3 different MAR sites for study with different quality of water and operation Determine virus levels by qPCR and infectivity assays This data along with previous studies will be used to develop criteria for estimating removal credit for virus by MAR Water & Environmental Technology Center