PUBLIC HEALTH ASSESSMENT
TRIUMPH MINE TAILINGS PILES
HAILEY, BLAINE COUNTY, IDAHO
The Triumph Mine Tailings Site is located in Triumph, Blaine County, Idaho. The site consists of two large tailings piles located on the south side of the East Fork River. Mine waste rock and the ruins of the mill and concentrator foundation ruins are located on the south side of the East Fork Road. Mine waste were generated from the processing of ore for silver, zinc, and lead from 1882 to 1957.
Environmental investigations have confirmed the presence of elevated concentrations of metals in mine waste, residential soil, household dust, groundwater, surface water, and sediments. Mine drainage may be distributing site contaminants into the adjacent wetlands. Wind erosion of the tailings pile especially in the summer months is redistributing the tailings to residential yards. The mine tailings have not been capped or removed. Residents may have been or could be exposed to metals in surface soil, household dust, ambient air, or mine tailings by incidental ingestion, inhalation, or dermal contact with site contaminants.
The Agency for Toxic Substances and Disease Registry (ATSDR) concludes that the Triumph Mine Tailings Site represents a public health hazard. The site has been classified as a public health hazard because the estimated exposures to the onsite contaminants could result in adverse health effects. Biological screenings for blood lead and urinary arsenic have been conducted on Triumph residents. The data from these screenings do not indicate that exposure is occurring at levels which would warrant medical intervention even though residents may have had or may have contact with site contaminants at concentrations which could potentially produce adverse health effects. This finding may indicate that the metals in the mine waste are less bioavailable or that residents are taking precautions to reduce their exposures to site waste. Biological samples obtained during the summer months indicate that exposure to site waste is increased when the tailings are actively transported by the wind or when residents would have more contact with the soil as demonstrated by increases in blood lead and urinary arsenic levels.
As long as the tailings remain uncapped or in the community, they pose a potential health risk to the residents and the environment. ATSDR recommends that residents be advised of public health measures that can be taken to reduce exposure to site contaminants until the tailings are removed or capped. In addition, biological screens for blood lead and urinary arsenic should be made available to residents on an annual basis during periods of peak exposure.
The public comment release version of this public health assessment was made available to the community surrounding the Triumph Mine Tailings Piles site. The document was dated March 26, 1997. Comments from the public were accepted until May 16, 1997. No comments were received from the public.
The Agency for Toxic Substances and Disease Registry (ATSDR) will evaluate the public health significance of this site in the public health assessment. ATSDR will determine whether health effects are possible and will recommend actions to reduce or prevent possible health effects. ATSDR is a federal agency within the U.S. Department of Health and Human Services and is authorized by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) to conduct public health assessments at hazardous waste sites.
The Triumph Mine Tailings Site is located in the community of Triumph, Blaine County, Idaho (see Figures 1 and 2). The site consists of two large tailings piles, the old Triumph Mine, a large pile of waste rock, and the mill/concentrator foundation ruins. The two tailings piles are separated by East Fork Lane. The two large tailings piles are located on the south side of East Fork Road. The upper tailings pile is located in Triumph and extends over an area of 13 acres. Single family residences are located on the west, east, south, and northeast sides of the upper tailings pile. A fence business borders the northwest corner of the upper tailings pile. The lower tailings pile is located west of Triumph and extends over 14 acres. Residences are located to the east of the lower tailings pile. The northeast portion of the lower tailings pile is fenced and used to pasture horses. The actual mine site is north of the East Fork Road and west of Triumph. The mill/concentrator foundation ruins are located on the north side of East Fork Lane. A large pile of blast waste rock lies north of the lower tailings pile below the mine.
The East Fork Wood River flows on the south side of the upper and lower tailings pile. Marshland lies between the river and the tailings pile. A drainage ditch originating from a spring flows through the upper tailings pile and discharges into the wetland located south of the upper tailings pile. The wetlands discharge surface water into the Wood River. Surface water drains from an abandoned mine and discharges into a drainage ditch on the lower tailings pile.
From 1882 to 1957, the Triumph Mine produced ore that was rich in silver, zinc, and lead. The ore was processed by crushing, grinding, and floatation to produce an ore concentrate. The materials remaining from processing, floatation tailings, were pumped as a slurry to two tailings piles. From 1882 to 1920, the tailings were deposited in the upper tailings pile, which typically received a coarser material. From 1930 to 1957, the tailings, which were finer-grain as a result of changes in the milling process, were deposited in the lower tailings pile.
In 1983, a local geologist had tailings samples analyzed for lead leachability using the Extraction Procedure Toxicity (EPT) test. Lead was detected in one of the extracts from the tailings samples at a concentration of 5.9 mg/L (1).
In 1986, the Division of Environmental Quality, Idaho Department of Health and Welfare collected a well water sample from a ranch about 3/4 of a mile downgradient to the Triumph Mine Tailings Site. Analytical results from the well sample did not contain metals at levels above federal drinking water standards (1).
In 1987, Blaine County Planning and Zoning referred the site to Environmental Protection Agency (EPA) Region X indicating concern about potential metal contamination from the site leaching into the East Fork of the Big Wood River and local groundwater (1). In 1988, the IDEQ collected surface water samples from drainage ditches near the tailings piles and from the East Fork of the Big Wood River and found elevated concentrations of arsenic, iron, manganese, and zinc (the samples were not analyzed for lead). Subsequent investigations by EPA contractors have revealed elevated levels of arsenic, cadmium, lead, and other metals in the mine tailings, in air samples collected downwind of the piles, in household dust from nearby residences, in sediments from the wetland areas south of the tailings piles, and in groundwater from nearby residential drinking water wells (1). The results of these sampling investigations are discussed in detail in the Environmental Contamination and Other Hazards section of this document.
ATSDR was requested by EPA Region X to evaluate the human health hazards posed by the contamination at the Triumph Mine Tailings Site on three occasions. In October 1991, ATSDR reviewed a draft Site Inspection Report for the Triumph Parker Mine Tailings Site. ATSDR concluded in a health consultation (October 21, 1991) that 1) exposure to lead and arsenic in residential soil, mine tailings, and household dust was possible at levels of public health concern and 2) consumption of the well water from the lower community well could pose a health threat. The consultation recommended that blood lead and urinary arsenic samples be collected from Triumph residents to determine if there was ongoing exposure to site contaminants. In addition, health education was recommended for the residents and health care professionals. Further characterization of the site, including sampling of the lower community well and indoor residential dust, were also recommended (2).
ATSDR reviewed environmental data from the first phase of the Removal Site Assessment (December 1991). In this consultation (June 3, 1992), ATSDR concluded that the site remained a public health concern. Levels of lead, arsenic, and cadmium in residential soils, mine tailings, and mine process foundation soils could pose a potential health risk. However, the extent of such a health threat could not be determined without biological sampling. As such, the consultation recommended additional biological sampling (i.e, blood lead, urinary arsenic), especially for toddlers and pregnant women, during the summer months when outdoor activities were most likely to occur (3).
In September 1993, ATSDR reviewed EPA Region X Removal Program's proposed interim action levels for lead and arsenic. These action levels were developed in conjunction with EPA's proposed removal action to reduce short-term risks from exposure to lead and arsenic in site soils and tailings. Specifically, the removal action would minimize direct contact with tailings and contaminated soils exceeding the acute health-based action levels. EPA proposed an action level for lead of 1,300 parts per million (ppm) in soil and a 3,000 ppm action level for arsenic in soil. ATSDR's review concluded that EPA's proposed action levels for arsenic and lead would not be protective of human health, especially for infants and young children (4).
As recommended in previous health consultations, ATSDR, in cooperation with the state and local health departments, conducted blood lead and urinary arsenic testing of Triumph residents in November 1991. Additional screens were conducted in July 1992 and July 1993 1992 by the Idaho Department of Health and Welfare. The results of these blood and urine screenings are discussed in the Health Outcome Data Evaluation section of this document.
The Triumph Mine Tailings Site was proposed for inclusion on the National Priorities List (NPL) in May 1993. Under CERCLA, ATSDR is required to conduct a public health assessment of all sites proposed to the NPL within one year of proposal.
ATSDR representatives Steve Richardson, Tina Forrester, Ann Walker, and Greg Thomas conducted a site visit to Triumph Mine Tailings Site on February 16, 1994. During the site visit, ATSDR observed the following:
- Access to the tailings piles, mine waste, and mill foundation were not restricted.
- Old mine equipment (haul trucks) remain at the mine.
- Mine drainage was flowing in a small ditch next to East Fork Road into the wetland.
- A population sign indicated that there are 49 residents in the Triumph community, 9 of
which are children.
- There is play equipment at one residence.
- There are residences located between the tailings piles.
- A very large pile of waste rock was observed north of the East Fork Road.
It was snowing heavily at time of the site visit. In previous ATSDR site visits, it was noted that there is no vegetative cap on the tailings piles. There is sparse vegetation on the residential yards.
ATSDR, with the assistance of the Idaho District Five Health Department, also held two public availability sessions during the afternoon and evening to gather community health concerns related to the site. Few residents attended the public availability sessions. Health concerns expressed by the community members who attended the public availability sessions are discussed in the Public Health Implications Section of this public health assessment. Prior to the ATSDR visit, officials of EPA Region X and EPA Headquarters (Washington, D.C.) had held a meeting with Triumph residents. At this meeting, EPA Headquarters officials indicated to the residents that the site would be deferred to the State of Idaho for the removal action. Furthermore, the site would possibly be delisted from the National Priorities List. For these reasons, the proposed EPA Region X removal action is currently on hold.
Site files were reviewed prior to the site visit to obtain relevant environmental and health data for the public health assessment. ATSDR met with representatives of EPA Region X, Idaho Department of Health and Welfare, and the Idaho District Five Health Department to obtain information for the public health assessment.
Approximately 65 persons live within one quarter mile of the site and 245 persons live within 4 miles of the site. Approximately 49 residents live in the community of Triumph. Mining operations ceased at Triumph Mines in the late 1950s. A fencing business operates on the northwest corner of the upper tailings pile. The majority of land under the lower tailings pile is owned by the Idaho Department of Lands (IDL). Although not a federal facility, a small portion of land under the lower pile may be owned by the Bureau of Land Management.
The community of Triumph obtains drinking water from two community wells and several private wells, one or more of which are located between the two tailings piles. The East Fork of the Big Wood River flows along the south side of the tailings piles and is a tributary of the Wood River. A domestic surface water intake, serving less than 10 people, is located about 15 miles down stream on the Wood River. The East Fork and the Wood River are both reported to be used for irrigation, sports fishing, and recreation.
Blood lead and urinary arsenic screens have been conducted of residents of Triumph. These screenings have taken place on three occasions, one in the late fall and two during active wind erosion of the tailings in the summer. The results of these screenings will be discussed in the Health Outcome Data Evaluation Section.
Residents of Triumph have reported specific health concerns during past public availability sessions. ATSDR will evaluate these concerns in detail in the Public Health Implications section of the public health assessment.
The following concerns have been expressed by Triumph residents:
1) What measures can an individual take to reduce exposure to metals in the soil?
2) Is it necessary for residents to participate in additional rounds of biological sampling to assure that exposures are not occurring during spring and summer months when there is increased outdoor activity and when tailings are wind-blown from the tailings piles?