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Gold King Mine Data, August 27, 2015

Data from Gold King Mine Response

EPA sediment samples collected August 15, 16, and 19, 2015 from the San Juan River and Lake Powell have been validated.

EPA has done a review of the data which included a comparison to screening levels for exposure during recreational use to determine if the metal concentrations are consistent with pre-event levels.

The metal concentrations of the samples were below soil / sediment recreational screening levels. Based on the sediment sampling results, sediment sample concentrations are trending toward pre-event conditions.


EPA has released additional water quality data from samples collected on August 15, 16, and 19, 2015 from the San Juan River and Lake Powell.

Each surface or bottom water sample was analyzed for 24 metals including arsenic, cadmium, lead and mercury.
 
Based on the sampling results, surface and bottom water concentrations in Lake Powell did not vary from pre-event conditions.  Based on sampling results, surface and bottom water concentrations have returned to pre-event conditions in the San Juan River.
 
The trend graphs on this website will be updated to include this data in the next few days.

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