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Follow-Up Monitoring Data from Gold King Mine Incident

Surface water and sediment samples are being collected and analyzed according to the September 2015, draft “Post Gold King Mine Release Incident: Conceptual Monitoring Plan for Surface Water, Sediment and Biology.”

After collecting data for a year, across a range of seasonal conditions, EPA will assess the data, consult with partners and decide what further monitoring or other follow-on actions may be appropriate.

The October and November follow-up monitoring data are available in an Excel table here. Fall 2015 Follow Up Monitoring Data (XLSX) (1 pg, 341 K)

The March 2016 follow-up monitoring data are available in an Excel table here. March 2016 Follow Up Monitoring Data (XLSX) (1 pg, 336 K)

The June 2016 follow-up monitoring data are available in an Excel table here. June 2016 Follow Up Monitoring Data (XLSX) (1 pg, 344 K)

August, September and October follow-up monitoring data are available in an Excel table here. August 2016 Follow Up Monitoring Data (XLSX)(1 pg, 637 K)

The Benthic Biological data collected between Aug. 22, 2016 and Oct. 4, 2016 are available in an Excel table here. Benthic Biological Data 2016 (XLSX)(1 pg, 107 K)

Follow-up monitoring data EPA collected during a November 2016 storm event and during the spring 2017 snowmelt are available in an Excel table here. GKM_Nov2016-June2017_Follow-up_Data_Final(5 pp, 915 K) .

These data have also been published to the Water Quality Portal, which publishes the data along with data collected by 400+ organizations throughout the U.S., including EPA, USGS, states, tribes, other federal agencies, watershed groups, and other local entities. More information about the Water Quality Portal, including how to use the Portal is available.

NOTE: As described in the comments field in the Excel data file and in the Water Quality Portal, Total Aluminum values cannot always be directly compared to New Mexico’s water quality standards for aluminum.

The final monitoring plan can be viewed here.

The press release about the fall data can be viewed here.