Most King County offices will be closed on Monday, May 28, for Memorial Day.  
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When values lower than the minimum analytical detection level (MDL) are reported, the MDL value for that analysis will be substituted on the chart. A data download will show for which dates the substitutions were made. Please select a sample location.

Note: Conventional data may be available for depths not shown on this chart. For complete dataset, please use data download function.