Perchlorate Levels Increase at San Pedro Well

City may pursue federal grant for filter; officials have spent
$3.5 million to treat perchlorate since 2001
Morgan Hill – Perchlorate levels have risen at San Pedro Well, prompting city officials to explore using a federal grant to pay for a new filtration system. 

If installed, the ion exchange filter would make San Pedro Well, located on Condit Road near the Aquatics Center, the third well in the city to be outfitted to treat perchlorate pollution caused by Olin Corporation. 

The filter would cost upwards of $350,000, but a federal grant might be available to cover 55 percent of the cost, said Public Works Director Jim Ashcraft. Currently the San Pedro Well is not operating. And, due to decreased water demand in the fall and winter months, officials say the city won’t need all 15 of its pumping stations again until May. 

Ashcraft said he’d continue to monitor monthly perchlorate levels at the San Pedro Well while exploring the grant opportunity. A filtration system would take about three months to install, he said, and he’s “guardedly optimistic” the city could win a federal grant through the Santa Clara Valley Water District by February 2007.

The San Pedro Well isn’t the first well Morgan Hill where high levels of perchlorate have been detected. Two other wells have been outfitted with ion exchange filters. Since 2001, the city has spent more than $3.5 million on these and other projects to treat perchlorate contamination. 

Olin Corp. is allegedly responsible for a 9-mile perchlorate plume, stemming from the operation of a road flair plant on Tennant Avenue in Morgan Hill. It travels south through San Martin and into north Gilroy. The Central Coast Regional Water Quality Control Board has ordered the company to clean up the pollution south of Tennant Avenue. Morgan Hill official have asked the regional board to extend the clean up order to include more of the city. The board may decide to act on the request at its next meeting in February 2007. Meanwhile, the city continues to pursue recovery of all perchlorate related costs so that water customers may be credited for amounts already spent on treating wells.

Ironically, the San Pedro Well was paid for and drilled by Olin Corp. in 2003. The company provided the pumping station after a municipal well on Tennant Avenue had to be temporarily shut down due to perchlorate contamination. 

On Sept. 7, lab results from tests performed monthly at the city’s pumping stations show perchlorate levels exceeding 4 parts per billion at the San Pedro Well on Condit Avenue. City policy recommends the use of water treatment at municipal wells when perchlorate levels reach that mark.

The city’s standard for treating perchlorate is more stringent than a proposed maximum contaminant level for perchlorate of 6 parts per billion being considered by the California Department of Health Services. The state presently has no maximum contaminant level for perchlorate. 

Health officials across the country continue to debate the dangers of perchlorate. The chemical is a type of salt that can cause thyroid damage if consumed in high enough concentrations. Studies have shown older people and pregnant women are particularly at risk.

In other news, the city council on Wednesday decided not to raise a 15 percent surcharge on water bills for perchlorate-related costs. The move will save rate payers $496,000 over the next two years. The council did, however, vote to allow a 2 percent water rate increase to take effect Jan. 1, 2007, to help cover cost increases associated with pumping groundwater. A typical single family residential customer currently pays about $40 per month for water usage, according to the city. The 2 percent increase will generate $125,000 per year. There is currently a $1.6 million debt for the city’s water works. Financial projections show the debt being paid off by rising revenues during the next four years.