Resin bonds with perchlorate to help clean out contaminated water in Saugus well.
By Lila Campuzano
It’s called styrene divinyl benzene. It looks like tiny golden globes and smells faintly like motor oil. Its job is making the Santa Clarita Valley’s groundwater near the Whittaker-Bermite site safe once more for drinking. And it’s been hard at work for about a month now at a well in Saugus, although the toxin it’s hunting has yet to make an appearance.
The resin is packed into two large tanks next to Bouquet Canyon Road just north of the Santa Clara River. Water pumped from a Valencia Water Co. well dubbed “Q2” runs through both tanks, where the styrene divinyl benzene puts a lock on molecules of perchlorate.
Eventually, when the resin maxes out its ability to bond with perchlorate, the compound will be taken away and burned, said Tim Peschman, a product manager for the environmental services division of USFilter. A new batch of the resin will take its place.
The process is called ion exchange, and USFilter provided the equipment and know-how.
Q2 is the first well in the Santa Clarita Valley to be fitted with a perchlorate-removal system, although it was the most recent well to test positive for the contaminant.
Ammonium perchlorate, a salt, is used as a booster in solid rocket fuel because perchlorate’s four oxygen atoms mean “(the fuel) burns faster and hotter,” Peschman said.
But solid rocket fuel has a short shelf life, he said. Before the danger of
perchlorate was understood, “about every six months, (workers) would take and jet wash it out of the rockets,” he said. “It winds up on the ground, goes into the soil.”
Since Santa Clarita Valley water retailers get about 40 percent to 50 percent of their water from the ground, perchlorate contamination was bad news locally, as well as in many other parts of the country where the defense industry operated through World War II. Local groundwater is mixed with State Water Project water before it is delivered to households.
But it wasn’t until 1997 that the effect of low doses of the chemical began to be studied. Part of that delay is due to the fact that small quantities of perchlorate are difficult to detect.
Perchlorate, an endocrine disrupter, was found to inhibit the effectiveness of the thyroid gland, especially in pregnant women and their unborn offspring. The discovery came long after Whittaker-Bermite had shut down.
Federal health officials haven’t yet set acceptable levels of perchlorate in drinking water. But the state of California says the amount should not exceed 4 parts per billion.
One part per billion would be about equal to a grain of sand in an Olympic-sized swimming pool.
In the Santa Clarita Valley, several wells around the former Whittaker-Bermite site were found to be contaminated with perchlorate and shut down in 1997. Q2 didn’t show a positive reading until April 2005.
“We didn’t know why it showed up in the first place,” since the well draws water across the Santa Clara River from the Whittaker-Bermite site, said Michael Alvord, assistant operations manager for Valencia Water. “Hydrogeological models showed that it was probably (last winter’s heavy rain).”
The 250-foot-deep well had been monitored continuously since 1997, Alvord said.
The firm immediately shut down the well, notified regulatory officials and called USFilter, which has had ion exchange systems up and running at several California locations.
Bob DiPrimio, general manager for Valencia Water, recalled his phone call to USFilter. I’m interested in an ion exchange process, and I need a permit in two days,” he recalled telling a USFilter official.
After the phone was dropped and picked up again, the Minnesota-based firm got right on it, he said last week at a media briefing. “Within a day and a half of pipes and everything arriving, it was up and running,” DiPrimio said. Ironically, the chemical hasn’t been detected in the well water since Q2 reopened in October.
Added Jeff O’Keefe of the state Department of Health Services: “The ultimate goal is to have containment right at the Whittaker boundary.”
Santa Clarita city and local water officials, along with the Whittaker Corp., U.S. Army Corps of Engineers, state Environmental Protection Agency and other government entities, have long been studying how to remedy the contamination at Whittaker-Bermite.
Groundwater removal is particularly tricky, since the Santa Clarita Valley actually has two underground water supplies centered mostly beneath the Santa Clara River.
The more shallow alluvial aquifer runs as much as 200 feet deep and is the water supply tapped by Q2. Water in this aquifer travels relatively quickly. The much deeper Saugus aquifer is held as reserve for drought periods, since it’s more expensive to pump water from this deeper source. This water travels only inches per year.
Perchlorate contamination has been found at both levels. Tainted wells are shut down and either replaced or capped until treatment can begin.
The same type of ion exchange system being used at Q2 will be put to work on two Castaic Lake Water Agency wells by the end of next year, said Ken Petersen of CLWA.
The two wells near the intersection of Magic Mountain Parkway and San Fernando Road tap into the deeper Saugus formation, he said. They have shut down since 1997. Water from those wells will be pumped into pipes and shipped to the Rio Vista Water Treatment Plant, which is just west of Q2. There the water will be treated in the same manner as Q2s.
The ion exchange system for the Saugus formation wells will be able to process about 2,200 gallons a minute, Petersen said.
Reactivating the Saugus formation wells will pull contaminated groundwater toward those wells and prevent it from flowing downstream, Petersen said. The treatment plant for the two Saugus formation wells will have to run for at least 30 years.
Still, the costs of the operation will exceed the federal grant. Styrene divinyl benzene cost about $175,000 per cubic foot, Peschman of USFilter said. Each tank holds about 250 cubic feet of the tiny golden globes.