PLAN TO STOP PERCHLORATE AGENCY EXPLORES POSSIBILITY OF USING WELLS TO CONTAIN TOXIC PLUME.

Byline: Nicholas Grudin Staff Writer

SANTA CLARITA - The Castaic Lake Water Agency is exploring a plan to tap highly contaminated water wells in order to contain the pollutant perchlorate from spreading further into the valley's drinking water supply.

The plan would call for running two wells that have been shut down since 1997. The wells were contaminated as a result of perchlorate, an ingredient in rocket fuel, that seeped into the groundwater from materials used to make explosives at the Whittaker-Bermite munitions factory. A plume of the chemical spread through the aquifer and caused the closure of five public wells.

Ongoing studies conducted by engineering consultants for CLWA and Whittaker Corp. indicate that the spread of perchlorate in the deep Saugus groundwater formation - a major area of pollution - could be contained if water is run out of two of the wells at a certain rate.

``(Engineers) discovered that running the wells at 1,200 gallons a minute would produce a capture zone that would keep the plume from continuing to spread westward,'' said Bill Manetta, retail manager of the Santa Clarita Water Division of the CLWA. ``We think this is a big step forward - basically, containing the plumes.''

Perchlorate can damage the functioning of the thyroid and could pose a danger to the development of infants in concentrations as low as 1 part per billion, according to the U.S. Environmental Protection Agency.

Concentration levels of perchlorate on the site of the Bermite munitions factory have been found as high as 58,000 ppb. The highest levels that tests have shown in the contaminated wells is about 40 ppb.

``There is definitely perchlorate contamination in the Saugus alluvium aquifer. There is contamination that needs to be dealt with,'' said Sara Amir, chief of the Southern California cleanup operations for the state Department of Toxic Substances Control.

``What we are trying to do is to make sure that the contamination in the groundwater doesn't go further. Part of evaluating different cleanup options is actually containing the plume of perchlorate.''

The Bermite pollution has been a divisive issue between the CLWA and Whittaker Corp. The two organizations have been at odds over who should pay for the costly cleanup, but the latest solution is seen as a step in the direction of cooperation.

Other regional water purveyors also view the new plan as a promising idea, both in its impact on the pollution plume and as a signal of cooperation.

``It is a plan that was developed by the purveyors and Whittaker-Bermite cooperatively,'' said Bob DiPrimio, president of the Valencia Water Company. ``I am very optimistic that this plan will work; we just need to move expeditiously to implement it.''

The plan entails tapping Wells No. 1 and 2, and running them at 1,200 gallons per minute. The water would then be treated to remove the perchlorate using an ion exchange process.

In order to actually implement the new plan, the CLWA would first have to conduct a three- to four-month test run to see if it worked, and to ensure that the ion exchange process was cleaning the water that is pumped.

Many other aspects of the perchlorate cleanup area also under consideration, according to the Department of Toxic Substances, including major soil excavation projects.

Nicholas Grudin, [phone]

nicholas.grudin(at)dailynews.com