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Gold King Mine Data, August 22, 2015

Data from Gold King Mine Response

EPA has released additional water quality data collected on August 16, 2015 from along the Animas and San Juan Rivers in New Mexico. 

EPA has released additional water quality data collected on August 13, 2015 and August 14, 2015 from along the Animas and San Juan Rivers in New Mexico. Based upon the surface water sample results in New Mexico surface water concentrations are trending toward pre-event conditions.

Background information:

To assess the impacts of the release at the Gold King Mine, water quality samples were collected from Navajo Nation at numerous intervals beginning on August 7, 2015. The August 7, 2015 data was collected for baseline purposes to understand river conditions at the Hogback, New Mexico monitoring location prior to the impact of the upstream contaminants from the Gold King Mine release. 

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 Friday, August 7, 2015, at four (4) locations prior to arrival of the plume along the Animas and San Juan Rivers in New Mexico. On Saturday, August 8, 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. These results are based on validated sampling data collected from August 7, 2015 to August 8, 2015. 

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