While officials continue to tackle perchlorate contamination on many fronts, recent tests on water from a well shut down five years ago showed levels of the suspected carcinogen still requiring specific action.
In April 2012, a well identified by officials at the Santa Clarita Valley Water Agency as Well V-205 was voluntarily shut down after low concentrations of perchlorate were found.
Well V-205 has been out of service ever since.
This month, however, testing done on the well’s water revealed perchlorate levels of 6.1 micrograms per liter – slightly above the maximum contaminant level, or MCL, of 6 micrograms per liter for perchlorate in drinking water.
The MCL is the state-set threshold for how much perchlorate can be found in water before it requires “treatment action.”
This well was taken out of service long before the levels reached the MCL, according to water officials.
“This wasn’t a surprise,” said Jim Leserman, senior engineer and project manager for the perchlorate remediation program for SCV Water. “Well V-205 has been subject to continuous monitoring, and a nearby well, V-201, was taken offline in April 2010 due to perchlorate.”
Water from this well has not been distributed since 2012.
“Treatment to remove perchlorate is an established and proven technology,” said Leserman. “We will evaluate the problem posed by the increased concentration and implement a solution, which could include a restoration plan that will treat V-205 in a manner similar to V-201.”
Two replacement wells are also planned west of Interstate 5, which will be funded as part of the terms of a legal settlement with the responsible parties.
Since first detected in groundwater wells in the Santa Clarita Valley in 1997, the predecessors to the new SCV Water (formerly Newhall County Water District, Santa Clarita Water Division, Valencia Water Company and Castaic Lake Water Agency) have worked diligently with state environmental and health regulators to address the problem and seek reimbursement for groundwater cleanup and replacement water supply costs from responsible parties, the Whittaker Corp. and its insurers.
Through extensive technical investigations, best practices were identified for control strategies, as well as the most effective and least costly treatment processes.
The result, according to SCV Water Agency officials, is a state-of-the-art Saugus Perchlorate Treatment Facility near Lowe’s off Bouquet Canyon Road, at the same location as SCV Water’s Rio Vista Intake Pump Station. It began delivering treated groundwater in January 2011.
At the start of this year, the facility had removed, treated and returned over 7 billion gallons — over 22,000 acre-feet — of groundwater for beneficial use. One acre-foot of water is about a football field flooded with a foot of water.
SCV Water has vigorously pursued treatment, as well as payment from Whittaker-Bermite.
“We will be working with the responsible parties — Whittaker-Bermite and their insurers — to develop cost effective treatment measures that protect our customers’ water quality, and protect them from cost increases due to mitigation,” said Dirk Marks, water resources manager for SCV Water.
“We will look at multiple options such as treating at existing sites, if treatment capacity at those sites can be increased, as well as an onsite treatment strategy such as the one in use at V201,” he said.
For more than 40 years, perchlorate was used as a solid fuel component in the manufacture of munitions, fireworks, flares, and other explosives at the Whittaker-Bermite site located south of Soledad Canyon Parkway and east of San Fernando Road.
As a result of all those “operations,” a known perchlorate contaminant plume has been identified in the SCV and several wells have tested positive for perchlorate.
Improperly disposed of waste leaked into the groundwater and contaminated the wells.
In addition to groundwater remediation efforts, there is a cleanup effort underway on the Whittaker-Bermite property under the jurisdiction of the state’s Division of Toxic Substances Control.
Once used as a medication to treat overactive thyroid glands, perchlorate can impair the function of normal and underactive thyroids. It has also been linked to problems with fetal development in pregnant woman.
In October 2007, state officials set a maximum contaminant threshold level for perchlorate at no more than 6 micrograms of perchlorate for every liter of water.
With regards to cleaning perchlorate-contaminated groundwater, the newly-completed Saugus Aquifer Treatment Plant is expected to pump and treat water extracted from 14 wells at a rate of 500 gallons a minute beginning next month.
The cleaned water, according to the plan, will be discharged into the Santa Clara River watershed to recharge SCV’s groundwater.
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