The Eagle Mine is an EPA (Environmental Protection Agency) Superfund Site. The ERWC monitors the site, but does not conduct the clean up. ERWC - Eagle Mine Limited is a separate non-profit organization created to inform the community about clean up efforts.
An overview of ERWC's monitoring efforts are described below. To learn more about the Superfund Site cleanup, please visit our Eagle Mine Superfund Site webpage.
- Eagle/Gilman Mine south of Minturn along Highway 24
- 235-acre site includes...
- Eagle Mine workings,
- the town of Gilman,
- eight former mine tailings piles,
- Rock Creek Canyon below Highway 24, and
- at least 14 waste rock piles
- Heavy metals such as lead, zinc, cadmium, arsenic, and maganese contaminated Eagle River
- Contamination killed fish
- Contamination threatened Minturn drinking wells
To read more about what the EPA, CDPHE, & ERWC Eagle Mine, Ltd. did to clean up the site, please visit our Eagle Mine Superfund Site webpage.
- Monitor fish populations with CDOW
- Monitor water chemistry with River Watch
Partners:
This site is one of the "Superfund" hazardous waste sites in Colorado. A site qualifies for the National Priorities List (NPL or Superfund list) when the U.S. Environmental Protection Agency (EPA) determines there is a release or threatened release of hazardous substances that may endanger public health, welfare or the environment. In Colorado, the lead agency for Superfund remediation may be either the EPA or the Colorado Department of Public Health and Environment (CDPHE).
The grant to provide public information regarding the Eagle Mine Superfund Site was initially sought by the Eagle River Watershed Council. Due to EPA rules regarding Technical Assistance Grants, it became necessary to form a separate non-profit corporation from the Eagle River Watershed Council. EML is that separate nonprofit corporation. ERWC - Eagle Mine Ltd. (EML) was formed to accept a Technical Assistance Grant (TAG) from the Environmental Protection Agency.
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Water Quality in the Eagle River below the Eagle Mine is impaired by high levels of zinc, copper, and cadmium, which impair aquatic life. Currently the River from Redcliff to the confluence with Gore Creek and through the Eagle Mine Site supports a Brown Trout population which is somewhat impaired by concentrations of these heavy metals. Water quality in this reach does not meet the table value standards for Cold Water Aquatic life (Class 1) set by the Colorado Water Quality Control Commission with regard to these heavy metals. As a result, sculpin do not inhabit the Eagle River from Belden downstream to the confluence with Gore Creek. Very few rainbow trout are found in this same river reach.
On June 9, 2008 the Colorado Water Quality Control Commission held a Public Rulemaking Hearing to reconsider water quality standards in the Colorado River basin, including the Eagle River. The water quality standards adopted by the Commission will be a pertinent issue in the 5 year review of Superfund Site activities.In the 5 year Superfund site review, CBS, as a responsible party, and the Hazardous Materials and Waste Management Division will attempt to arrive at an agreement that defines future cleanup that will be required. In these negotiations, the Hazardous Materials and Waste Management Division seeks further cleanup activities that are expected to result in a reduction of zinc loading to the River of between 37 and 41 pounds per day. Current zinc loading is approximately 120 pounds per day, thus the proposed further action will likely cause a 33% reduction.
While this level of reduction will certainly cause an improved aquatic environment and healthier brown trout population, it is not expected that water quality will be improved to the extent necessary for the Eagle River to support a healthy rainbow trout population in the reach between the Eagle Mine and Gore Creek.
For a simple explanation of how mining activities affect water quality, read a paper prepared by Wendy Naugle of the Colorado Department of Public Health and Environment for school children.
Download the slide presentation prepared by John Wooding Ph.D. on how zinc concentrations in the River affect fish population and health.
On July 29, 2008, EPA, the Colorado Department of Public Health and the Environment, and ERWC Eagle Mine Ltd. conducted a tour of the Eagle MIne Superfund site. A breafing document for the tour prepared by Warren Smith of CDPHE is attached as "Eagle Mine Superfund Site Tour, July 29, 2008"
The Eagle Mine Annual Report - 2008 prepared for CBS Operations Inc by NewFields provides a summary of environmental data collected during 2008. The report also summarizes design, construction, inspection, operation, maintence, and community relations activities conducted in 2008.
A preliminary Ground Water and Surface Water Monitoring Plan for 2009 describes the monitoring which is anticipated to be conducted to further identify the sources of metals pollution to the Eagle River. Data collected will likely contribute to the identification of future remedial cleanup activities.
The Statement of Work for 2009 provides a plan for analysis of alternative remedial actions for reducing the loading of zinc and other heavy metals to the Eagle River.
The Eagle Mine Site - Belden Groundwater Extraction System Performance Report provides information on how an experimental groundwater extraction has performed. Movement of groundwater into the stream is beleived to be a signifiacnt source of the loading of heavy metals, particularly following snowmelt at the mine site.
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Since 1989 the Hazardous Material and Waste Management Division of the State Health Department asked the Division of Wildlife (DOW) to sample the Eagle River for fish. Sampling means collecting as many fish as possible which inhabit a defined river reach for the measurement (weight and Length) and examination of individuals. The collection process is accomplished by introducing a mild (do not want to harm the fish) electric current into the water to attract and temporarily stun (for only seconds) the fish so that they may be safely and quickly netted.
The request to collect information about the fish inhabiting the Eagle River was part of a response to the "pink snow" incident where water from the river used to make snow for skiing on Vail Mountain made pink snow because of the dissolved metal ions in the river. Dr. John Woodling (PhD) was the person from the DOW who did that first survey. A number of sites were monitored -- above the Eagle Mine, at the mine, and several sites below the mine.
The project was seen in a positive manner from the public so the river has been sampled each April from 1990 through the current year. Normally fish sampling is not done in the spring; however spring sampling demonstrated the impact of the high metal ion concentrations on the fish present in the winter months. The sole reason behind the sampling program was to assess the efficacy of the Eagle Mine CERCLA (Comprehensive Environmental Response, Compensation, and Liability Act, more commonly known as Superfund) cleanup project.
A number of sites are sampled: a control site at Arrowhead, at just north and south of Minturn, just below Two Elk Creek, Two Elk Creek, just below the effluent of the mine water treatment plant, at the mine, and at the confluence of the Eagle and the Homestake near Red Cliff.
Since the count is taken in the spring, ice chopping must be the first priority. Ice chopping is necessary to eliminate ice overhang the bank, which provides a location for the fish to hide. After the chopping is complete, one hopes for a few warm days and good weather so all the chopping that has been done is not undone before the fish counting.
It is morning and the volunteers are going strong.
One of these two individuals ended up falling into the river, but the identity remains confidential.
Fish counting day involves a number of people from the DOW, Forest Service, and volunteers from several fishing guide concerns and the Eagle River Watershed Council. At some point during the count of a reach, physical measurements of the river reach must be taken. Equipment must be set up, which includes a generator, electric lines, electrodes, and fish holding pens that must stay in moving water. One container (known as the fish cart) moves with the line as it progresses up the river, another dual net holding pen is anchored in the stream near the fish counters that contains unmeasured and measured fish. The unmeasured fish are moved by bucket to the shore where species is noted as well as total length and weight. The measured fish are moved back to another bucket and then moved to the "counted" net pen in the river. Two passes are made and if the sweep is good (statistically determined -- the second sweep should net less than 50% of the first sweep), the equipment is packed up and the crew moves to the next site. If the statistics are not met, a third pass is conducted.
Some of the crew is paying out the electric lines; the fish cart can be seen in center foreground.
At some point during the counting, the physical dimensions of the river reach studied must be determined. These folks are measuring the length of the reach.
The line is about to move up the reach for the first pass. Note the electric line, which must be
long enough to reach from the generator to the electrodes and the entire length of the reach
under study.
The line consists of persons working electrodes (and catching stunned fish at the same time),
backup netters who catch fish the stunners miss,and people carrying nets who move the fish
from the stunners to the fish cart.
The fish in the fish cart are moved to the dual net holding pen which is located very near the
individuals assessing the fish and recording the results. After the fish are measured, they are
moved to the other side of the holding pen. All the inventoried fish in the second pen are
released once the count is deemed satisfactory.
The fish are moved on land in buckets from the "uncounted" section of the dual net pen in the
river on land to be weighed and measured.
The graduated tray on the scale holds the fish in place while the mesurements are made.
John Woodling is the gentleman making the measurements.
The data on each fish is duly recorded. John takes this data, regresses it, analyzes it, and
writes the report. A link to that report is included on this web page.
The most current report (as a PDF file) covers the period of April 1990 to April 2007: Woodling Eagle River Fish Study. John also gave an ERWC Water Wise Wednesday presentation this year on the same subject: Woodling Eagle River Fish Study - Presentation .
Fish are not the only living creatures affected by metal levels in the river. A case in point is presented in the following PowerPoint slides: The Case of the Missing Mayfly .
The following is a real "Fish Story."
The Remarkable Story of SO4, a Trout of the Eagle River
On April 4, 2000 a brown trout was collected on the Eagle River at a sampling site just upstream of Two Elk Creek. The fish was 202 mm long (just under 8 inches) Total length (TL), weighed 73 grams (g) and was injected with an elastomer tag identified with the code SO4. This fish was just about three years of age based on a comparison with the length frequency distribution of all other brown trout collected at that site on that day. SO4 was released back into the water an hour or so later.
SO4 resulted from the brown trout spawn of fall 1996. The fertilized egg developed over the winter and the fry emerged from the gravel in June or so of 1997. SO4 evidently liked the particular reach of the Eagle in which it was first captured, because SO4 was collected again in 2001, 2003, 2005 and 2009. This spring, SO4 was 285 mm long. SO4 had only grown 82 mm (about three inches) in the intervening nine years. Actually the fish had only grown about 17 mm (0.64 inches) in the four years between 2005 and 2009. SO4 was 12 years old in 2009 and had yet to reach a length of 308 mm TL (one foot long).
A growth history for SO4 was determined (Figure One) using the mean TL of oneyear- old and two-year-old brown trout collected at this sampling location over a 18 year period of record. An assumed total length of 24 mm was also used for the fingerling brown trout that would be SO4 at time of emergence as a swim-up fry in 1997. SO4 had almost stopped growing by the age of four years. Perhaps most of the fish’s energy had been put into spawning efforts since an age of three or four and little energy was expended on growth. Brown trout often stop growing once the fish starts spawning each fall.
Figure One
The relative weight [1] (Wr) for SO4 had little variation from 2000 through 2009 (Figure 2). This brown trout weighed less than all other brown trout of the same size each time SO4 was collected as indicated by a Wr value of less than 1.0. SO4 is a skinny fish. The head of SO4 is much wider than the body of the fish when viewed from above in 2009. SO4 has always been collected at the same site, the Eagle River just downstream of the effluent from the treatment plant that removes metals from water emanating from the Eagle Mine Site. The mean Wr of all brown trout collected at this site is lower than expected in other Colorado Rivers. The metals remaining in the stream may account for the reduced weight of SO4 compared to all other brown trout of the same size. However, the fish appeared as fit as ever in 2009 and may survive yet another year.
Figure Two
An age of 12 is rather rare for river dwelling brown trout in Colorado. A length of less than 12 inches at an age of 12 is also rather rare. A longer length would be expected. No other tagged brown trout has survived this long in the Eagle River from Redcliff, Colorado to Avon, Colorado.
John Woodling
April 6, 2009
Written for the Eagle River Watershed Council
[1] The relative weight of a fish is the actual weight of the organism divided by the standard weight of all fish of the same length of that species. A Wr of less than one means the fish in question has a weight less than the 75th percentile of all fish of that length of that species.
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