The Pleasanton City Council signed off on a response plan with near- and long-term strategies to address levels of certain human-made chemicals found in the local groundwater supply Tuesday night.
The move came after new state testing requirements led the city and Zone 7 Water Agency officials to discover their wells contain levels of synthetic compounds in the so-called "per- and polyfluoroalkyl substances (PFAS) family," which were once commonly used for surface coating as an oil and water repellent but have been phased out to a major degree amid health and safety concerns.
"I'm concerned. I would rather have a report that says we have a way to get rid of it and stop it now, a cost-effective way," Councilman Jerry Pentin said at the close of the hour-long discussion.
"I don't think we're going to find any of those things. I think we're going to find this to be a very expensive process, and we're going to have to see whether we can survive without our own ground wells, or we'll have to depend on Zone 7 and Zone 7 can provide us with clean water," he added. "We have positioned ourselves, from what I've heard tonight, at least, as being proactive as we possibly can right now."
Vice Mayor Karla Brown added, "Now, we're taking the steps to make sure the water we provide to our residents is, in fact, clean and safe. And as soon as we found out there was a question, we shut that well down (Well 8) and we were proactive."
The State Water Resources Control Board's Division of Drinking Water issued orders earlier this year for local water agencies to test their sources for PFAS chemicals, including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), which are unregulated contaminants.
Exposure to unsafe levels of PFOA and PFOS over time could result in health concerns such as cancer, liver damage and developmental effects to fetuses during pregnancy, according to city staff.
PFAS have been extensively used commercially as protectant agents for items such as paper or cardboard packaging, textiles, nonstick coatings on cookware and firefighting foams. While PFOA and PFOS have been phased out by American manufacturers, replacement substances in the PFAS family were developed and appear to behave in a similar toxicological manner, according to city staff.
Concerns remain about past and current PFAS compounds contaminating water sources, especially groundwater wells near sites where the chemicals could be found more extensively, such as landfills, industrial properties, fire response sites and wastewater treatment plants.
"This issue is very concerning ... The reason this is so concerning is because it's persistent and it's bioaccumulative," resident and environmental advocate Jill Buck told the council.
"When I see something that's measured in parts per trillion, it doesn't comfort me. That says, 'This is bad stuff. This is really toxic,'" Buck added.
For Pleasanton, 25% of the public water supply comes from three city wells and the rest is supplied by Zone 7, whose primary source is water delivered through the State Water Project, supplemented by local wells.
Initial Zone 7 tests found some groundwater wells to be above the notification levels for PFOS or PFOA, with one well -- Mocho-1 -- testing above the response level (70 parts per trillion) for both.
For the city's active wells, Well 5 and Well 6 tested above the notification level for PFOS only while Well 8 tested above the response level for combined PFOS and PFOA.
As a result, Mocho-1 and Well 8 have been designated as last priority, for use only when absolutely needed for meeting the water demand. City officials noted that its Well 8 has not been in operation since the initial testing and would only be used "under abnormal conditions such as extreme peak demand periods or if there are failures of other supply facilities."
The council on Tuesday unanimously endorsed the action plan developed by city staff to address the contamination concerns based on the initial testing results for Pleasanton's water supply.
The near-term plans include operational strategies such as quarterly testing for PFOA and PFOS, coordinating with Zone 7 on future testing and operations, and supporting efforts to determine potential sources of PFAS in the region that could be impacting local wells.
Also in the short term, the city will continue to focus on public notification, which includes the PFAS webpage on the city website and the PFAS brochure residents have been receiving in the mail with their utility bill.
Long range, the action plan calls for evaluating PFAS treatment options at Wells 5, 6 and 8; a comprehensive water capacity and distribution evaluation; incorporating financial impact estimates of new PFAS regulations into the water rate study; better tracking PFAS-related legislation; and revisiting regional water supply considerations.
"The city is committed providing safe, clean and reliable water to our customers," City Manager Nelson Fialho said in a statement after the meeting. "Our short- and long-term workplan ensures that we are using objective information to inform the public regarding emerging water safety standards and pursuing meaningful engineering solutions and technology to ensure the state's public heath goals are met in the future."