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Gold King Mine Data, August 17, 2015

Data from Gold King Mine Response

To assess the impacts of the release at the Gold King Mine, water quality samples were collected from the Northern Border of New Mexico to Navajo Nation at numerous intervals beginning on Aug. 6, 2015.

Samples were taken prior to the plume’s arrival to establish a baseline for water quality comparisons. Each surface water sample was analyzed for 24 metals, including arsenic, cadmium, lead and mercury. Surface water samples were collected on Thursday, August 6, 2015, at two (2) locations prior to arrival of the plume along the Animas and San Juan Rivers in New Mexico.

On Wednesday, August 12, 2015, nine (9) locations were sampled after arrival of the plume. EPA has continued to take additional samples to document the change in the concentration of metals in the river. EPA has shared this data with state, local and tribal officials in New Mexico to assist them in their decisions regarding the on-going use of water resources.  Based upon the surface water sample results in New Mexico, surface water concentrations are trending toward pre-event conditions.

Water quality data from Aug. 6 and 12, 2015, on the Animas and San Juan rivers in New Mexico are in the Excel files below:

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