Community Update for September 19, 2012

Wastewater treatment and sewer collection systems are a vital part of a community's infrastructure and these services are necessary to keep things flowing smoothly for residents. But with this comes a responsibility to protect the health and safety of all who live here and protect our environment. As the company charged with operating and managing the City of Richmond's wastewater treatment facility and collection system, Veolia takes its role very seriously. Among the measures that we take to protect the community is the monitoring of odors and emissions that are natural byproducts of running a wastewater treatment plant.

In this edition of our Community Update, we want to address Hydrogen Sulfide, or H2S, which is produced by bacterial breakdown of organic materials and human and animal wastes. It is often a cause of concern for residents.We'd like to take the opportunity to share additional information about H2S and how it's managed safely in the treatment process.

What is H2S?
Hydrogen sulfide is a colorless, flammable, extremely hazardous gas with a "rotten egg" smell. Some common names for the gas include sewer gas, stink damp, swamp gas and manure gas. It occurs naturally in crude petroleum, natural gas and hot springs.

How do I know if I'm being exposed to H2S?
H2S has a "rotten egg" smell at low levels, but it's important to note that similar or unusual odors are not always indicators of exposure to H2S. In a highly industrialized community like Richmond, with refineries, rail transportation, manufacturing plants, petroleum tank farms and shipping ports, odors and H2S can be linked to numerous sources.

How do you monitor H2S to ensure residents are not in danger from exposure?
In Richmond, there are 7 monitoring stations that detect and measure levels of H2S.They are located along the north and south fence lines of the plant, in Brickyard Cove, Point San Pablo Yacht Club, in two locations at Washington Elementary School, and Richmond Plunge. These are closely monitored and if concentrations rise to a level which presents a potential threat to health and safety, City and Veolia responders take action to investigate the cause and mitigate the situation. Veolia has paid for the installation of the Brickyard Cove meter and the rest are maintained and funded by the City. Link to the online monitoring data: https://www.mysmartcover.com/h2s/

At what level is there a threat to personal health and safety?
H2S monitor alarm setpoints are set at conservatively low levels. Veolia, the City and the Air Board are notified when there is H2S measured at 30 parts per billion (ppb).Because these meters are set so low, we are made aware when H2S is detected at the 30 ppb level, and then we investigate to try and determine the source, then monitor to ensure that levels do not rise to a point where there is the potential for risk. For context, the Air Board uses an outdoor air quality measure of 30 ppb over a one-hour period as the Ambient Air Quality Standard for H2S in the Bay Area. Often, there will be a brief elevation, or spike, that is the result of an anomaly or transient odor, but only when the elevation is elevated and sustained for a period of time is an active mitigation required.

What are the symptoms of H2S exposure?
At low concentrations, you may experience minor eye, nose and throat irritation, including tearing of the eyes, a cough or shortness of breath. People with asthma may experience breathing difficulties. Moderate concentrations produce more severe instances of these symptoms, and may also produce headaches, dizziness, nausea and fatigue. Some people have a greater sensitivity to H2S and can experience symptoms at low, safe levels. If you have any health concerns, you should seek medical attention.

There is an abundance of information available on Hydrogen Sulfide (H2S) and we make several fact sheets available on our website atwww.richmond.veoliawaterna.com, including an OSHA Fact Sheet, a document that explains the measurement levels of H2S and a link to real-time readings of the H2S meters placed throughout the Richmond community. We want you to be informed and reassured that we take your health and safety very seriously.If you have any questions, please call us at (510) 412-2001.