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U.S. EPA Releases Monitoring Plan to Evaluate Conditions in the Animas and San Juan Rivers

Christie St. Clair

March 24, 2016

U.S. EPA Releases Monitoring Plan to Evaluate Conditions in the Animas and San Juan Rivers

Washington – The U.S. Environmental Protection Agency today released its final monitoring plan for the Animas and San Juan rivers following the Aug. 5, 2015, Gold King Mine incident. The agency also posted on its Gold King Mine website the results of surface water and sediment sampling collected as part of its yearlong effort to gather a robust set of scientific data to evaluate ongoing river conditions.

The conceptual monitoring plan is designed to gather a robust set of scientific data to consistently evaluate river conditions over time and evaluate impacts to public health and the environment. In September 2015, EPA released the draft conceptual monitoring plan, Post Gold King Mine Release Incident: Conceptual Monitoring Plan for Surface Water, Sediment and Biology for comment. Since then, EPA has been working with state, local and tribal partners to develop a consistent monitoring approach to gather scientific data to assess conditions in the Animas and San Juan rivers. The final conceptual monitoring plan is available on EPA’s website. EPA continues to work with states and tribes on any additional monitoring needs and federal funding to support their activities. States and tribes are also designing complementary jurisdiction-specific monitoring plans. EPA has made $2 million in initial funding available to launch these monitoring efforts.

Under the conceptual monitoring plan, EPA is examining water quality, sediment quality, biological community and fish tissue at 30 locations under a variety of flow and seasonal river conditions. The sampling locations are located within Colorado, Southern Ute Indian Reservation, New Mexico, Ute Mountain Ute Reservation, the Navajo Nation and Utah, spanning Cement Creek, the Animas and San Juan rivers, and the upper section of the San Juan arm of Lake Powell.

When fully implemented, the conceptual monitoring plan will provide EPA, state, local governments and tribes a robust set of scientific data about water quality in the rivers and will help to explain the fluctuations over time and location based on seasonal factors that influence river flow, such as precipitation and snow melt. Initial monitoring data collected from 27 locations during the fall are below risk-based recreational screening levels and consistent with pre-event data which are limited in many areas outside the upper Animas. The spring sampling event is currently taking place, and will be followed by additional sampling planned in June and in the fall. EPA will also coordinate with local jurisdictions and tribes to sample the rivers during heavy rain events in the summer.

View the latest sampling results

View the final conceptual monitoring plan