The new state health goal for perchlorate levels in drinking
water may mean dozens of South Valley wells will no longer be
considered unsafe, but for now, it won
’t change much for residents whose wells are contaminated with
the toxin.
The new state health goal for perchlorate levels in drinking water may mean dozens of South Valley wells will no longer be considered unsafe, but for now, it won’t change much for residents whose wells are contaminated with the toxin.
Residents who qualify will continue receiving bottled water, and until Morgan Hill city officials evaluate the new guidelines, they will continue to consider water unsafe from wells that measure above the previous “action level.”
“We haven’t decided what, if any, level of perchlorate we’re going to allow in the water,” Mayor Dennis Kennedy said Friday.
The state Office of Environmental Health Hazard Assessment (OEHHA) announced Thursday that it set a public health goal for perchlorate in drinking water at 6 parts per billion. The established standard makes California the first state to regulate perchlorate, a primary ingredient in rocket fuel as well as highway safety flares manufactured at Olin Corp.’s plant in Morgan Hill.
The chemical was detected in unsafe amounts in as many as 450 South Valley wells, announced in January 2003.
The former action level for perchlorate, or the level at which water providers must notify their customers, was 4 ppb. The higher standard announced Thursday caused some to question whether the change would affect the cleanup of local wells and contaminated soil or bottled water deliveries to impacted homes.
Roughly 70 percent of local wells in the affected area from Morgan Hill south to the northernmost parts of Gilroy have tested between 4 and 6 ppb. While no public wells in Gilroy have tested positive, a handful of private wells have – none above 6 ppb. Under the new state guidelines, those wells are considered safe.
“Just don’t take away our bottled water,” said Sandy Petersen, a San Martin resident who attended Friday’s regular meeting of the Perchlorate Citizens Advisory Group.
Olin Corp., which manufactured flares at a Tennant Avenue factory that spread a perchlorate plume through southern Morgan Hill and into northern Gilroy, has been delivering bottled water to residents whose wells measure as low as 2 ppb.
Rich McClure, Olin’s representative and project manager on the South Valley clean up effort did not answer phone calls asking whether the company’s policy would change.
David Athey, an engineer with the state Regional Water Quality Control Board – the lead agency in the perchlorate clean up – told Petersen it is unlikely that Olin will stop its deliveries.
“I doubt very seriously, from my standpoint, that anything will change that quickly,” he said.
The City of Morgan Hill currently does not operate wells that test above 4 ppb. Wells are tested monthly and, in the past, have been shut down temporarily when levels do climb above 4 ppb. The Tennant Avenue well, across the street from the Olin plant, was closed in 2002 and a replacement well dug; Olin is reimbursing the city for costs.
The city has also installed and paid for – Olin has so far refused – a perchlorate treatment plant on the Nordstrom well, one of the city’s largest and newest. Closing Nordstrom, along with two Dunne Avenue wells, during last summer’s hot spells when levels reached more than 5 ppb stressed water reserves almost to crisis levels.
California recommends shutting down wells with perchlorate levels at 40 ppb or higher. City Manager Ed Tewes said officials would evaluate the new public health standard before summer.
“We are not proposing to have any changes until we have that evaluation,” Tewes said. “We have a number of wells that are off-line now, and yet we have sufficient capacity to meet our water demand. However, in the summer, our water demand raises significantly, so … we will need more water capacity to meet our water demand.”
That could mean using water from wells that test between 4 and 6 ppb.
The Santa Clara Valley Water District took out an ad in Friday’s Morgan Hill Times to address the state’s decision.
“We were kind of afraid people would be confused and think we aren’t going to take care of their wells anymore,” said water district spokesman Mike DiMarco.
“Our goal has not changed. We still want to clean up the groundwater basin, so a change in a state number is sort of irrelevant to us,” DiMarco said.
“For organizations that produce water, we have to use whatever the limit is that’s established. So right now, we will be using the 6 parts per billion in relation to what we produce in water for the customer,” Gilroy City Manager Jay Baksa said. “(Gilroy has) never had a hit on our city wells, so the immediate is, there’s no issue with us.”
While residents likely will be forced to “live with” wells that measure up to 6 ppb, they can rest assured that the goal for cleanup is still to leave groundwater perchlorate-free, Kennedy said.
“The fact that this level’s been set at 6 (ppb) doesn’t relieve Olin of the responsibility to clean up the soil to the levels they were before,” Kennedy said.
“This won’t affect cleanup,” said Eric Gobler, an engineer with the Regional Water Quality Control Board. “And I say that because the (board’s) policy is to clean up to background.”
“Background” refers to the amount of the toxin that would naturally occur in groundwater. For perchlorate, the background level is zero.
The new 6 ppb standard caused varied reaction among those attending Friday’s advisory group meeting. Some said it is too high; others said it’s too low.
The public health standard completes the first of two steps necessary to set a working drinking water standard. The 6 ppb target is based solely on health concerns, or what is safe for more vulnerable consumers, such as fetuses, children, pregnant women and the elderly. Perchlorate can impair thyroid function and cause tumors.
Next, the state Department of Health Services will set a maximum contaminant level (MCL), a standard that comes as close to the health goal as possible to the extent technologically and economically feasible. This level might not be set for another year.
Assemblyman John Laird, who attended Friday’s regular Perchlorate Citizens Advisory Group, said the public health goal may trigger a debate process to revise the standard.
“I think overall (6 ppb) is not a bad start,” said Laird, whose 21st district includes Morgan Hill and San Martin, but not Gilroy. “Lower would have been better … but 6 is realistic enough that we can pull it back if we have a discussion that goes that way all along.”
Environmental groups are calling 6 ppb too high, saying it is six times higher than initial Federal Environmental Protection Agency recommendations. To date the federal government has not set either a PHG or an MCL.
“I’m very pleased that the state has stepped up to the plate,” said Sylvia Hamilton, who chairs the Perchlorate Citizens Advisory Group. “That not only tells our state and our community, but our country, that perchlorate is something that needs to be dealt with.”
Hamilton said she was disappointed that the public health goal was not set at 2 ppb – the low end of the range that was considered.
“It’s important to remember that 6 and 4 aren’t that far apart,” said Tom Mohr, an engineering geologist with the Santa Clara Valley Water District. Perchlorate tests can have a 20 percent margin of error, he said, and levels often fluctuate over time.
Others sounded off on the standard, as well. Senators Barbara Boxer (D-Calif.) and Dianne Feinstein (D-Calif.) praised the establishment of a standard, while the Sierra Club and Clean Water Action both condemned the standard as too high for vulnerable consumers.
The Central Coast Regional Water Quality Control Board will meet in public Friday, March 19, in the Salinas City Council Chambers Rotunda, 200 Lincoln Ave., Salinas. The Morgan Hill/San Martin Olin perchlorate case is number 18 on the agenda and is not expected to be heard before 1 p.m. Olin Corp. representatives are expected to be present. The complete agenda can be found at www.swrcb.ca.gov/rwqcb3/
Staff writer Carol Holzgrafe contributed to this story.
