As most of you are undoubtedly aware, the city has recently
temporarily closed two of its wells. We want you to know that we
take water quality extremely seriously and our actions to close the
wells are far above and beyond what the law requires the city to do
in these circumstances. We believe that it is best to err on the
side of caution. All drinking water supplied by the city meets or
exceeds all state and federal standards.
As most of you are undoubtedly aware, the city has recently temporarily closed two of its wells. We want you to know that we take water quality extremely seriously and our actions to close the wells are far above and beyond what the law requires the city to do in these circumstances.
We believe that it is best to err on the side of caution. All drinking water supplied by the city meets or exceeds all state and federal standards.
In brief, the city has 13 active wells and recently tested them all for perchlorate. No detectable perchlorate was found in all wells in January. However, a sample from the February tests indicated that two wells, Nordstrom and Condit, had levels of perchlorate slightly above the State Department of Health Services (DHS)Action Level of 4 parts per billion. (Nordstrom was 6 ppb, Condit was 5 ppb.)
We took both of these wells offline immediately when these initial results came in on Feb. 24. As recommended by DHS, we took additional samples for “confirming” tests in accordance with the State’s testing protocols. The test results received Friday, Feb. 28, showed that both wells were below the detection limit of 4 parts per billion.
The DHS action level is not a drinking water standard, but is instead a level at which a drinking water supplier should inform its customers about the presence of a contaminant. While the city’s action to shut down the wells was not required, we believe that it is best to take a very conservative approach in this matter. Both of these wells have remained off line and will be tested and evaluated again in 30 days. All drinking water supplied by the city meets or exceeds all state and federal standards.
We have received many calls at the city during the past week. Here is a summarized response of some of the more frequently asked questions:
Q: How does a customer know which well serves their home?
A: All of the water pumped from city wells is blended in the distribution system. In theory, all of our wells serve all of our customers.
Q: How often is the city required to test for perchlorate?
A: The City is required to test for perchlorate twice this year. However, even though not required to do so, we will be testing all wells monthly in 2003.
Q: What is the maximum contaminant level for perchlorate in drinking water?
A: There is currently not a state maximum contaminant level for perchlorate in drinking water. Current state law requires the Department of Health Services to develop a standard by January 2004. The current action level of 4 parts per billion requires staff to notify the council and is not the drinking water standard for perchlorate. Many water agencies in Southern California routinely deliver water to their customers that contains greater than 4 parts per billion of perchlorate.
Q: How widespread is the contamination?
A: At this time, the Santa Clara Valley Water District and Olin Corp., under the direction of the state Regional Water Quality Control Board is still sampling wells to determine the extent of the contamination. As I write this, their web site reports that 235 of the 607 wells they have tested south of Morgan Hill have had detectable amounts of perchlorate. All of these wells are independent of the city’s water system.
Eco-Web Page of the Week: The Santa Clara Valley Water District web site has additional information on perchlorate available at www.valleywater.org
Anthony Eulo is the environmental programs manager for the city and assistant to the city manager. He welcomes questions, comments and thoughts and can be reached at teulo\@ch.morgan-hill.ca.gov or 779-7247.
