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EPA Statement on Data from New Mexico to Navajo Nation from Gold King Mine Release

Farmington, New Mexico - August 13, 2015: Today, EPA has released additional water quality data from Aug. 7 to Aug. 8, 2015 for the Animas and San Juan Rivers from the Northern Border of New Mexico to Navajo Nation. Based upon the surface water sample results in New Mexico surface water concentrations are trending toward pre-event conditions.

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. 7, 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 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 Aug. 7 to Aug. 8, 2015.

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