For Utilities Commission Meeting [August 16, 2022]
TO: Honorable Chairperson and Commission
APPROVAL: Thomas J. Crowley, P.E., Utilities Manager
Title
Presenting the 2022 Public Health Goals Report (PHGs) pursuant to the Calderon-Sher Drinking Water Act of 1996, and the 2021 Consumer Confidence Report (CCR) on Drinking Water.
(RECEIVE AND FILE)
Body
BACKGROUND
The Calderon-Sher Drinking Water Act of 1996 added new provisions to the California Health and Safety Code which mandate that a report be prepared every three years to provide water quality information to the public in addition to the Consumer Confidence Reports (CCR) mailed to all customers each year. The law requires that a public hearing be held for the purpose of accepting and responding to public comment on the report. The City of Rialto chooses to produce the report annually and hold PHG public hearings annually.
Under the Calderon-Sher Safe Drinking Water Act of 1996, public water systems in California serving greater than 10,000 connections must prepare a report containing information on the: detection of any contaminant in drinking water at a level exceeding a PHG; estimate of costs to remove detected contaminants to levels below the PHG using best available technology; and health risks for each contaminant exceeding a PHG.
The initial report was due July 1, 1998, and subsequent reports are due every three years thereafter. This report has been prepared to address the requirements set forth in Section 116470 of the California Health and Safety Code. It is based on water quality analyses during the years of 2019, 2020, 2021. For analyses that were not performed during those years, the State requires the most recent data available.
A workgroup of the Association of California Water Agencies (ACWA), Water Quality Committee, has prepared suggested guidelines for water utilities to use in preparing PHG reports. These guidelines were used in the preparation of the attached report and when appropriate includes tables of cost estimates for best available technology. The State provides ACWA with numerical health risks and the categories for health risk information for contaminants with PHGs.
ANALYSIS/DISCUSSION:
California Health and Safety Code section 116365 requires the State to develop a PHG for every contaminant with a primary drinking water standard or for any contaminant California is proposing to regulate with a primary drinking water standard. A PHG is the level of concentration which poses no significant health risk if consumed for a lifetime. The process of establishing a PHG is a risk assessment based strictly on human health considerations. PHGs are recommended targets and are not required to be met by any public water system.
The state office designated to develop PHGs is the California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment. The PHG is then forwarded to the California State Water Resources Control Board Division of Drinking Water and Environmental Management (SWRCB) for use in revising or developing a Maximum Contaminant Level (MCL) in drinking water. The MCL is the highest level of concentration that is allowed in drinking water for a contaminant. California MCLs cannot be less stringent than federal MCLs and must be as close as is technically and economically feasible to the PHGs. The SWRCB is required to take treatment technologies and cost of compliance into account when setting MCLs.
The attached 2021 PHGs report information is required by law because one contaminant detected is above the Public Health guidelines. Arsenic is a semi-metal element in the periodic table. The PHG for arsenic is 0.004 ppb and the MCLG is 10 ppb. Arsenic was found to occur in one groundwater well, City Well 2, with detection 3.1ppb.
Although 3.1 ppb was the highest arsenic level detected at one point in time amongst multiple tests performed throughout the year, the average arsenic detection level for 2021 was only .52 ppb, which is very close to the PHGs level of .004.
Over the past 7 years, the highest arsenic level detected dropped from 4.7 ppb in 2015 to 3.1 ppb in 2021, resulting in a 34% decrease:
During the same period, the average arsenic level has dropped from 2.8 ppb in 2015 to .52 ppb in 2021, resulting in an 81% decrease:
Overall, the amounts of Arsenic detected between 2015 and 2021 has dropped each year since 2015 and is making progress to a “No Detection” Arsenic level result in future PHGs reporting. The state does not require treatment when the contaminant level is less than 50% of the PHG. Currently, the State only requires 1 test per 3 years, which is less frequent than others which require more sampling and testing.
The Public Health Goals Report will provide detailed information such as:
• The category or type of risk to health that could be associated with each constituent.
• The Best Available Technology (BATs) that could be used to reduce the constituent level.
• Estimate of the cost to install that treatment if it is appropriate and feasible.
The 2021 edition of the Public Health Goals Report is included as Attachment 1 and the Consumer Confidence Report is included as Attachment 2.
This item was presented to the Water Subcommittee on May 25, 2022. The 2022 public hearing will be scheduled as part of a regular City Council and Rialto Utility Authority Meeting scheduled for June 28, 2022 and will be noticed as required by law for public hearings.
FINANCIAL IMPACT:
The PHG Public Hearing will result in minimal expenses for public notification and printed materials to the Public Works Department, within budget available in the general fund program accounts.
RECOMMENDATION
Staff recommends that the Utilities Commission Receive the 2022 Public Health Goals Report and 2021 Consumer Confidence Report (CCR) on Drinking Water.