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Emergency Response Monitoring Data from the Gold King Mine Incident

This page includes links to data and related information collected as part of the Gold King Mine response.

Below you will find:

Map of Gold King Mine Release Sampling

The map below provides links to Gold King Mine Response sample data. These data are pulled from the sets uploaded on an ongoing basis. You may also view individual data sets by date posted in spreadsheet form.

CLICK HERE for a full-screen map

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Sampling Data Results

To assess the impacts of the release at the Gold King Mine, water quality samples were collected from the Animas and San Juan Rivers at numerous intervals beginning on Aug. 7, 2015. Samples were collected from the Northern Border of New Mexico to Navajo Nation.

EPA compared the data to screening levels for exposure during recreational use. By August 12, 2015, EPA's test results were showing metal concentration levels throughout this area below surface water and sediment/soil recreational screening levels and returning to pre-event conditions. By September 2, 2015, sampling results were showing that levels were back to and maintaining pre-event levels. Based on previous monitoring events it has been shown that metal concentrations may fluctuate from time to time because of water surges due to heavy rains or other events that may change the water flow rates or volume.

We will continue to add data to these result tables sets:

New Mexico and Navajo Nation in EPA’s Region 6

Colorado and Utah in EPA’s Region 8

Arizona in EPA’s Region 9

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San Juan County, Colorado

Dec. 17, 2015 Update:  At the request of La Plata County, Colorado, EPA collected water and sediment samples at the mine entrance to test for an expanded suite of potential contaminants. To view the analysis and related data files, click here.

Table Key

The column headers in the Gold King Mine sample result tables are explained in the key below.

Site No – A code the designates which EPA Region collects the sample

0010958

Region 6

A8K9

Region 8

R9080515

Region 9

Sample No – Every sample is given a unique sample identification number
Location – Every sampling location (identified by latitude and longitude) is given a unique identifier
CAS No – The CAS number identifies the metal
Analyte – Is the material (metal) for which the sample has been analyzed

Total or Dissolved

T

The total (or entire) sample is analyzed, including suspended sediment and material that has dissolved in the water.

D

The dissolved sample includes only the material that has dissolved in the water.

Result -  The data result that gets compared to the Method Detection Limit (MDL) and the Reporting Limit to determine if the result is a true detection of the analyzed material.

Detected

Y

Yes. The material was detected in this sample.

N

No. This sample is considered a non-detect. The number in the result column is equal to or less than the Method Detection Limit (MDL) and/or the Reporting Limit.

Result Qualifiers

J

The result is estimated because the result is less than the Reporting Limit but great than or equal to the Method Detection Level (MDL).

J-

The result is estimated, but may be biased low.

J+

The result is estimated, but may be biased high.

U

Non- Detect. The metal was analyzed for, but was not detected above the level of the Method Detection  Limit (MDL)

UJ

Non-Detect. The metal was analyzed for, but was not detected. The Method Detection Limit (MDL) is an estimate and may be inaccurate or imprecise

UB

Non-Detect. The metal was reported as a non-detected due to contamination of the blank sample.

Sampling Date – The date the sample was taken

Sample Time – The time the sample was taken in Mountain Time

MDL – The Method Detection Limit is the lowest level that we can confidently say we have a detection

Reporting Limit – The limit at which we say we can accurately quantify the result

Matrix – Type of sample analyzed

QA Comment – Identifies the level of Data Quality Assurance review. Level 2 (L2) is the highest level of review.

Latitude and Longitude – Coordinates for unique location identifier

Analysis – Identifies EPA analytical method

Sampling data by date posted

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. Data sets are organized by the date on which they were posted to the website.

December 17, 2015

At the request of La Plata County, Colorado, EPA collected water and sediment samples at the mine entrance to test for an expanded suite of potential contaminants. To view the analysis and related data files, click here.

November 16, 2015

This data submission presents data for sediment samples collected on 10/5, 10/8, and 10/12 from the San Juan River.

This data submission presents data for surface water samples collected on 10/5, 10/8, and 10/12 from the San Juan River.

Data for this date. (sediment, water)

October 28, 2015

This data submission presents data for sediment samples collected on 9/30 from the San Juan River.

This data submission presents data for surface water samples collected on 9/28 and 9/30 from the San Juan River.

Data for this date. (sediment, water)

October 23, 2015

EPA surface water and sediment samples collected on 10/8, 10/9 and 10/14 from locations along the Animas River in New Mexico.

Data for this date. (sediment, water)

October 19, 2015

EPA surface water samples collected on 9/28 from locations along the Animas River in Colorado.

Data for this date. (water)

October 15, 2015

EPA surface water samples collected on 8/16, 8/17 and 8/19 from locations along the Animas River in Colorado.

Data for this date. (water)

October 14, 2015

EPA surface water and sediment samples collected on 9/30 and 10/1 from locations along the Animas River.

EPA sediment samples collected on 9/28 and 10/1 from locations along the Animas River.

EPA surface water samples collected on 10/1 from locations along the Animas River.

This data submission presents data for surface water samples collected on 9/24; and, sediment samples collected on 9/24 from the San Juan River.

Data for this date. (sediment, water)

October 5, 2015

EPA sediment samples collected on 9/28, 9/29, and 9/30 from locations along the Animas River. 

EPA surface water samples collected on 9/28, 9/29, and 9/30 from locations in the Animas and San Juan Rivers.

This data submission presents data for surface water samples and sediment samples collected on 9/24 from locations along the Animas River.

Data for this date. (sediment, water)

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October 1, 2015

EPA sediment samples collected on 9/18, 9/19, and 9/22 from locations along the Animas River.

EPA surface water samples collected on 9/18, 9/20, 9/21, and 9/22 from locations in the Animas and San Juan Rivers.

EPA sediment samples collected on 9/6, 9/7, 9/17, 9/18, 9/19, and 9/20 from locations along the Animas River.

Data for this date. (sediment, water)

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September 30, 2015

EPA sediment samples collected on 9/23, 9/24, and 9/25 from locations along the Animas River.

EPA surface water samples collected on 9/23, 9/24, and 9/25 from locations in the Animas and San Juan Rivers.

Data for this date. (sediment, water)

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September 29, 2015

This data submission presents data for surface water samples collected on 9/14 from the Animas River. 

This data submission presents data for surface water samples collected on 9/21; and, sediment samples collected on 9/17 and 9/21 from the San Juan River.

Data for this date. (sediment, water)

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September 28, 2015

EPA sediment samples collected on 9/16 and 9/17 from locations along the Animas River.

This data submission presents data for surface water and sediment samples collected on 9/2, 9/3, 9/8, 9/9, 9/11, 9/12, 9/13, 9/17, 9/18, 9/19, 9/20, and 9/21 from the Animas River.

Data for this date. (sediment, water)

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September 25, 2015

EPA sediment samples collected on 9/21 and 9/22 from locations along the Animas River.

EPA surface water samples collected on 9/19 from locations in the Animas and San Juan Rivers.

Data for this date. (sediment, water)

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September 24, 2015

This data submission presents data for surface water and sediment samples collected on 9/15 from the San Juan River.

EPA sediment samples collected on 9/6 and 9/7 from locations along the Animas River.

Data for this date. (sediment, water)

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September 23, 2015

EPA surface water samples collected on 9/17 from locations in the Animas and San Juan Rivers.

Data for this date. (water)

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September 22, 2015

EPA sediment samples collected on 9/16 and 9/17 from locations along the Animas River.

Data for this date. (sediment)

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September 21, 2015

EPA sediment samples collected on 8/28, 8/30, 9/8 and 9/9 from locations along the Animas River.

EPA sediment samples collected on 9/15, 9/16 and 9/17 from locations along the Animas River.

EPA surface water samples collected on 9/15 and 9/16 from locations along the Animas River.

Data for this date. (sediment, water)

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September 19, 2015

EPA sediment samples collected on 8/26 through 9/4 from locations along the Animas River.

EPA surface water samples collected on 9/5 from locations along the Animas River.

Data for this date. (sediment, water)

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September 18, 2015

EPA sediment samples collected on 9/10 through 9/14 from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on 9/10 through 9/14 from locations in the Animas and San Juan Rivers.

Data for this date. (sediment, water)

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September 17, 2015

EPA surface water samples collected on 8/24 and 8/25 from locations in the Animas River.

This data submission presents data for surface water and sediment samples collected on 9/10 from the San Juan River.

This data submission presents data for surface water samples collected on 8/21, 8/23-25, and 8/27-29; and, sediment samples collected on 8/21, and 8/23-28 from region 9. 

Data for this date.  (sediment, water)

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September 16, 2015

EPA sediment samples collected on 9/2, 9/3 and 9/4 from locations along the Animas River.

EPA sediment samples collected on 8/30, 8/31, 9/1 and 9/2 from locations along the Animas River.

This data submission presents data for surface water and sediment samples collected on 9/3 from the San Juan River.

Data for this date.  (sediment, water)

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September 15, 2015

EPA sediment samples collected on 9/7 through 9/9 from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on 9/7 trough 9/9 from locations in the Animas and San Juan Rivers.

Data for this date.  (sediment, water) 

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September 11, 2015

EPA sediment samples collected on 9/5 and 9/6 from locations along the Animas and San Juan Rivers..

EPA surface water samples collected on 9/4 and 9/5 from locations in the Animas and San Juan Rivers.

Data for this date.  (sediment, water) 

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September 10, 2015

EPA surface water samples collected on 9/6 from locations in the Animas and San Juan Rivers.

EPA sediment samples collected on 8/31 from locations along the San Juan River.

EPA surface water samples collected on 8/31 from locations in the San Juan River.

Data for this date.  (sediment, water) 

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September 9, 2015

EPA sediment samples collected on 9/2, 9/3 and 9/4 from locations along the Animas and San Juan Rivers.

Data for this date.  (sediment, water) 

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September 8, 2015

EPA sediment samples collected on 9/1 from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on 9/2 from locations in the Animas and San Juan Rivers.

EPA surface water samples collected on 8/31 from locations in the Animas and San Juan Rivers.

EPA surface water samples collected on 8/27, 8/29, 9/1, 9/3 from locations in the Animas and San Juan Rivers.

EPA sediment samples collected on 8/31 and 9/1 from locations along the Animas River.

EPA sediment samples collected on 8/27and 8/28 from locations along the Animas River.

Data for this date.  (sediment, water) 

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September 5-7, 2015

No new data available on September 5-7.

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September 3-4, 2015

EPA sediment samples collected on August 29, 30, and 31 from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on August 26, 28, and 30 from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on August 25, 26 and 27 from locations in the San Juan River.

EPA sediment samples collected on August 26 and 27 from locations along the San Juan River.

EPA surface water samples collected on August 22, 2015 from Lake Powell.

EPA sediment samples collected on August 22, 2015 from Lake Powell.

Data for this date.  (sediment, water) 

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September 2, 2015

EPA sediment samples collected on August 28th from locations along the Animas and San Juan Rivers.

EPA surface water samples collected on August 16, 17, 20, 21, 23 and 24 from locations in the Animas River.

Data for this date.  (sediment, water) 

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September 1, 2015

No new data available on September 1.

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August 31, 2015

EPA sediment samples collected on August 25th from locations along the San Juan River.

Data for this date. (sediment)

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August 30, 2015

EPA sediment samples collected on August 11, 13, 14, 16, 18 and 19, 2015, from the Animas River.

EPA sediment samples collected on August 23, 25, 26 and 27, 2015, from the Animas and San Juan Rivers.

EPA surface water samples collected on August 7, 8, 9, 10, 11, 12 and 13, 2015, from the Animas River.

EPA surface water samples collected on August 23, 24, and 25, 2015, from the Animas and San Juan Rivers.

Data for this date. (sediment, water)

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August 29, 2015

EPA sediment and water quality samples collected on August 24, 2015 from the San Juan River.

Data for this date. (sediment, water)

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August 28, 2015

EPA sediment and water quality samples collected on August 17 and 18, 2015 from the San Juan River and Lake Powell.

EPA sediment and water quality samples collected at locations along the Animas and San Juan Rivers. Sediment data collected on August 15-22 and Aug 24, 2015, and the surface water samples collected August 12-22, 2015.

Data for this date. (sediment, water)

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August 27, 2015

EPA sediment data from samples collected on August 15, 16, and 19, 2015 from the San Juan River and Lake Powell.

EPA water quality data from samples collected on August 15, 16, and 19, 2015 from the San Juan River and Lake Powell.

Data for this date.  (sediment, water)

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August 24-26, 2015

No new data available on August 24, 25, or 26.

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August 23, 2015

EPA surface water samples collected on August 16 and 17, 2015 from along the Animas River.
EPA sediment samples were collected on August 13, 2015 and August 14, 2015 from 12 irrigation ditches along the Animas River and five locations in the Animas River. 

Data for this date. (sediment, water)

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August 22, 2015

EPA water quality data collected on August 16, 2015 from along the Animas and San Juan Rivers.

Data for this date. (water)

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August 21, 2015

EPA sediment samples collected on August 11, 2015 and August 14, 2015 along the Animas and San Juan Rivers in New Mexico.

EPA sediment samples were collected on August 13, 2015 and August 14, 2015 from irrigation ditches 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.

Data for this date. (sediment, water)

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August 20, 2015

No new data available on August 20.

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August 19, 2015

EPA is collecting water and sediment samples from Lake Powell near the inlet of the San Juan River. Given the recent sampling results of reduced metals in the plume, EPA expects no significant impacts to Lake Powell associated with the Gold King Mine release.  Map showing sampling locations along the San Juan River and Lake Powell

EPA sediment samples were collected on August 10-13 along the Animas and San Juan Rivers. Water quality samples were collected on August 13-15, 2015 on the San Juan River between Farmington, New Mexico and Mexican Hat, Utah.

Data for this date. (sediment, water)

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August 18, 2015

EPA sediment samples were collected from irrigation ditches at two locations along the San Juan River. Water quality samples were collected on August 12, 2015 are from the Animas River.

Data for this date. (sediment, water)

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August 17, 2015

EPA water quality data were collected in the Animas and San Juan rivers in New Mexico on Aug. 6 and 12, 2015, including locations in Aztec and Farmington.

Data for this date. (water)

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August 16, 2015

No new data available on August 16.

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August 15, 2015

EPA water quality data were collected on August 9, 2015, in the San Juan River between Farmington and Shiprock.

Data for this date. (water)

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August 14, 2015

EPA sediment samples were collected on August 11, 2015 in the Animas River from Bakers Bridge to north of Durango.

Data for this date. (sediment)

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August 13, 2015

Water quality samples were collected on August 7 - 11, 2015 from the Northern Border of New Mexico to Navajo Nation at numerous intervals.

Data for this date. (water)

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August 12, 2015

Water quality samples were collected on August 5 - 9, 2015 from the Northern Border of New Mexico to Navajo Nation at numerous intervals.

Data for this date. (water)

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August 11, 2015

No new data available on August 11.

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August 10, 2015

Water quality sampling data from the 2015 Gold King Mine release. Included are

  • Preliminary water sampling data, Animas River, August 5.
  • Summary of the evaluation of pH data collected, August 6.
  • Summary of EPA Surface Water Sampling of Select Metals, to August 8.

Data for this date. (water)

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