The City of Morgan Hill received bad news this week when two
municipal wells tested above the state
“action level” for perchlorate and were shut down. The source of
the contamination is unknown.
The City of Morgan Hill received bad news this week when two municipal wells tested above the state “action level” for perchlorate and were shut down. The source of the contamination is unknown.
Water from Morgan Hill’s remaining public wells all test non-detect and residents are receiving only water from those wells. In addition, the county health officer, Dr. Martin Fenstersheib, has said that he does not expect harm to come to people drinking water with levels below the action level of 4 parts per billion.
“Morgan Hill city water meets or exceeds all state regulations for safety,” said Jim Ashcraft, public works director.
“We don’t know if it’s Olin,” Mike DiMarco, spokesman for the Santa Clara Valley Water District, said about the latest contamination. The Olin plant is the acknowledged source of the perchlorate contaminating hundreds of wells from Tennant Avenue south to Leavesley Road in Gilroy. That source site is 3,000-feet from the Condit well and at least 7,000-feet from the Nordstrom well.
The Condit well results showed a perchlorate level of 5 parts per billion in only one test; Nordstrom showed 6 ppb, also in only one test of several. Results in all other tests were “non-detect”. The Nordstrom well is located on the corner of Murphy and East Dunne avenues at Nordstrom Park. The Condit well is on the corner of Barrett Avenue and Condit Road, both east of Hwy. 101.
The decision to shut the two wells down Monday was Ashcraft’s.
“The wells showed non-detect in January (Jan. 15), tested positive on Feb. 21 and non-detect again at the confirming test on Feb. 25,” he said.
The Nordstrom well had previously tested 7 ppb in December 2000, 6.2 on Jan. 18, 2001 and 6.0 on Jan. 22, 2001. Until this latest test, Nordstrom has been testing non-detect.
All other currently operating city wells came back non-detect. Two of the city’s wells are off line.
THE $710,000 WELL
In April 2002 the city closed another municipal well because of perchlorate contamination. The Tennant well, located directly across the street from the Olin Corp. site, was closed permanently and a new well dug near the soccer fields on San Pedro Avenue. The public was notified in mid-May, the first public sign of what has become a problem of major concern in South County.
Olin Corp. was presented with a bill for $710,000 covering the cost of drilling the new well; the city and Olin are still negotiating over payment.
The California Department of Health Services requires a second and confirming sample to be taken a month after a detect is found in a water sample. Then the two levels are combined and the water agency acts on that level.
Ashcraft said the regulations instructed them to average the 6 and 5 ppb with the two non-detect levels – as if they were zero – and, if those levels are below the 4 ppb action level – which they were – no action need be taken.
He noted that non-detect does not necessarily mean zero – it just means below 4 ppb.
“Tests that show zero to 3.9 ppb are not reliable,” he said.
The Department of Health Services allows cities to provide customers with municipal water with levels up to 10 times the action level, which in the case of perchlorate, would be 40 ppb. The only requirement is that the customers must be notified.
By shutting down wells with such low levels of the chemical, the city reacted well ahead of state rules.
“These are steps far in excess of the state DOHS requirements,” Ashcraft said. When perchlorate levels are between the action level – 4 ppb – and the maximum contaminate level – 40 ppb – all the city is required to do is notify residents within 30 days.
During a presentation to the City Council Wednesday night, Ashcraft said he intends to request permission at the council’s next meeting – March 19 – to drill a new well as a backup, in case one or both of the wells cannot be reopened. A new well might be necessary to keep the city from being short of water during the summer months.
“We will keep the wells off line for at least another month,” Ashcraft said.
Council members asked for monthly reports on the status of well water.
“The city will be proactive in providing frequent updates to the council and residents,” said Ed Tewes, city manager.
WHO, IF NOT OLIN
Conventional wisdom – backed up by geologists and water district engineers – has always held that the water flows south, southeast from the Olin plant and wells north of the source should be safe. All above ground water – streams and creeks – south of Cochrane Road flow south. For underground water – the aquifer – the dividing line is of what is the proposed Cisco site, near Metcalf Road, in Coyote Valley flows south.
“It’s very odd for it to be going up-gradient,” Ashcraft said.
DiMarco said there are possible sources other than Olin.
“There used to be several fertilizer plants in the area,” he said. The plants imported “bulldog soda” from Chile partially composed of sodium perchlorate.
“The source could also be left-over flares or fireworks or even methamphetamine labs,” he said.
Another theory is that the city wells’ pumping action could possibly bring the water north.
Perchlorate is a by-product from the manufacture of rocket fuel and explosive products, including the flares and automobile air bags.
DiMarco noted that United Technologies Corp. used to test rockets at its facility on Metcalf Road, in Coyote Valley, northwest of the city.
“We just don’t know,” DiMarco said.
Ashcraft said he received the positive results on Monday, Feb. 24 and the non-detect results from the confirming test on Friday, Feb. 28. The water district was notified after business hours that same day. City Manager Ed Tewes was also notified on Friday. The two wells were shut down Monday morning.
Tewes sent an e mail to the City Council Monday morning, Ashcraft said, after his department was certain they were satisfying state regulations. The public was notified at Wednesday night’s council meeting, nine days after the first positive results were received.
Since the news that perchlorate had traveled far from the Olin site was announced in mid-January, more than 950 private wells, and those of both San Martin Water District companies, have been tested. Results received so far show two wells with levels of between 40-100 ppb, two between 20-40 ppb; nine between 10-20 ppb and 176 between 4-10 ppb.
The original boundaries of suspected perchlorate contamination from the Olin site were Monterey Road on the west, Center Avenue on the east, Tennant Avenue north and, at first, Masten Avenue to the south. Those boundaries have expanded south to Leavesley Avenue and east to Foothill Avenue to include newly-found contaminated wells.
Olin is paying to have all wells in the area tested and is providing free bottled water for residents.
In the meantime, several San Martin residents have joined in a class-action lawsuit against the Olin Corp. and others to force health monitoring and treatment. Property values on land with contaminated wells have also been affected.
DiMarco said there are several dozen private wells in the area between the Nordstrom and Condit wells and the Olin site.
Ashcraft said private wells are the responsibility of the SCVWD, not the City of Morgan Hill.
If those well owners want their water tested, Ashcraft said, they should call the water district’s perchlorate hotline 408-265-2607 x2649. DiMarco said they could also try calling the Olin number: 800-295-6141.
Ashcraft said that most, if not all, residents with the private wells within the city limits are also connected to the city water system for drinking water. The private well water is generally used for irrigation.
Up-to-date information on the on-going perchlorate issue is available at www.valleywater.org
