1. Pasadena Water and Power Public Health Goals Report Presented by David Kimbrough, Ph.D. Water Quality Manager City Council September 9, 2013 Item 14

2. Pasadena Water and Power Summary 2 Maximum Contaminant Levels (MCL) Public Health Goals (PHG) AgencyCalifornia Department of Public Health (CDPH) Office of Environmental Health Hazard Assessment (OEHHA) RequirementMandatoryNon-Mandatory ReportingAnnual Water Quality Report (CCR) Triennial Public Health Goal Report Provided toCustomersGoverning Body

3. Pasadena Water and Power Protecting Public Health CDPH regulates drinking water for Community Water Systems (CWSs), like PWP Some of these standards regulate the chemical content of drinking water These standards are called “Maximum Contaminant Levels” or MCLs 3

4. Pasadena Water and Power Setting MCLs CDPH sets MCLs by first finding the lowest concentration of any given chemical which has no adverse health effect This concentration is called the PHG The PHG is determined by the OEHHA CDPH sets the MCL as close to the PHG as is technologically and economically feasible The PHG is generally lower than the MCL 4

5. Pasadena Water and Power Complying with Standards PWP routinely monitors its water sources for compliance with Drinking Water Standards  Results are sent directly to CDPH Annual Water Quality Report or Consumer Confidence Report (CCR) Triennial Public Health Goal Report  Report to the City Council  Details which chemicals are found in our sources at concentrations below the MCL, but above the PHG  Provides estimated cost of treatment to reduce the concentration below the PHG 5

6. Pasadena Water and Power Exceeding Standards All of the water that PWP delivers to its customers is less than the MCL. The following items are present in our source water at concentrations greater than the PHG, but less than the MCL:  CTC  PCE  TCE  cis-1,2-DCE  Perchlorate  Nitrate  Lead and Copper  Total Coliform Bacteria  Arsenic  Uranium  Gross Alpha  Fluoride  Chromium VI - Cr (VI) 6

7. Pasadena Water and Power Chromium(VI) CDPH announced proposed MCL on August 23, 2013  Public hearing to receive comments will be on October 11, 2013 PWP’s groundwater concentrations exceed the PHG, but are below the proposed MCL  PWP’s levels are fairly typical  Most CWSs have Cr (VI) in their sources greater than the PHG Currently, no Best Available Technology  Ion exchange technology may be effective Requirement or Water Source Nanograms per liter (ng/L) Parts per billion (ppb) Public Health Goal200.02 Proposed MCL10,00010 PWP Groundwater2,000 – 7,0002-7 MWD Supply100-3000.1-0.3 7

8. Pasadena Water and Power Chromium(VI) The PHG is 20 ng/L (nanograms per liter) or 0.02 parts per billion (ppb). CDPH announced a proposed MCL of 10,000 ng/L (10 ppb) on August 23, 2013. The public hearing to receive comments on the proposed MCL will be on October 11, 2013. PWP’s groundwater sources have Cr (VI) concentrations greater than the PHG but below the proposed MCL. PWP’s wells have between 2,000 and 7,000 ng/L of Cr (VI). Water purchased from the Metropolitan Water District of Southern California contains between 100 and 300 ng/L Cr (VI). Most CWSs have Cr (VI) in their sources greater than the PHG and PWP’s levels are fairly typical. Currently, there is no Best Available Technology but recent research has indicated that ion exchange technology, similar to that used to remove perchlorate may be effective. 8