PUBLIC HEALTH ASSESSMENT
ANNIE CREEK MINE TAILINGS
LEADE, LAWRENCE COUNTY, SOUTH DAKOTA
The Annie Creek Mine Tailings Site is located about 3.5 miles west of the town of Lead in theBlack Hills region of South Dakota. The site includes an area once known as Reliance Tailingsand areas along Annie and Spearfish Creek, where sedimentation of mine tailings have occurred. Mine tailings were deposited at the headwaters of Annie Creek as a result of gold miningactivities that occurred from 1907 to 1916. Arsenic and other heavy metals were released intoAnnie Creek as a result of a crib dam failure which retained the tailings at the old Reliance Mine.
The primary contaminant of concern is arsenic. Arsenic contamination has been detected insurface water, groundwater, alluvial soils, stream bed sediments and biota. The potential existsthat vacationers and seasonal residents may be occasionally exposed to arsenic through ingestionof surface water and groundwater or by incidental ingestion of contaminated sediments from thestream beds of Annie and Spearfish Creek. ATSDR has concluded that Annie Creek MineTailings presents a no apparent public health hazard since the available data do not indicate thatthe occasional exposures to site contamination are occurring at concentrations that would be expected to produce adverse health effects.
Area residents expressed concern about the impact of releases of arsenic from the site on 1) thequality of the Spearfish municipal water supply 2) the quality of game fish in Spearfish Creekand 3) the potential for arsenic to migrate from Annie Creek and Spearfish Creek into waterwells located at residences along the two streams.
Information collected during preparation of the public health assessment indicated that theSpearfish municipal water supply is not impacted by the contamination in Annie Creek. Themunicipal water supply is not obtained from Spearfish Creek.
Arsenic was detected in two species of fish, the trout (Spearfish Creek) and the mountain sucker(Annie Creek). Although arsenic was detected in an edible species of fish, the brown and brooktrout, the levels detected would not be associated with any adverse health effects for therecreational consumer.
Arsenic was detected in the groundwater and in the surface water of Annie Creek. The wells atresidences around Annie and Spearfish Creek were not used for drinking water. If thegroundwater or surface water was ingested by a vacationers or seasonal residents at the reportedconcentrations, no adverse health are expected to occur.
There have been no adverse health effects reported by area residents or public health officialsconcerning exposure to arsenic contamination at the Annie Creek Mine Tailings Site.
In 1989, Wharf Resources built a waste rubble facility in the upper reaches of the Annie Creekdrainage to stabilize the original Reliance Tailings pile. A non-time critical removal action wasimplemented for Annie Creek Mine Tailings. The removal action included: covering exposedareas of arsenic-contaminated tailings with clean soil; drainage controls to divert surface waterrunoff; institutional controls which included deed (residential use) and access restrictions;surface and groundwater monitoring; and public information programs to address potentialhuman risk posed by the site. These actions will reduce the impact of the Reliance Tailings onAnnie and Spearfish Creek. ATSDR recommends no further action for the Annie Creek MineTailings Site.
The Annie Creek Mine Tailings Site (Old Reliance Tailings) is located about 3.5 miles west ofthe town of Lead, Lawrence County, South Dakota, about 4 miles west of the Terry Creek Roadturnoff from Federal Route 85. Access to the old tailings is limited by an 8-foot wire meshfence, gates, a security guard, and a cover of waste rock. The waste rock cover ranges from 60 to 150 feet over a large portion of the old Reliance Tailings.
The mine tailings dispersed along Annie Creek are the result of mining and milling activities thattook place between 1907-1916. The tailings cover a 5 acre area deposited at the headwaters(upper 1/4 mile) of the Annie Creek. The old tailings (Old Reliance Tailings) were producedduring gold mining activities that occurred from 1907 to 1916 at the site. Wharf Resourcescurrently operates two open pits (Annie Creek Mine and Foley Ridge/Annie Arm Mine), an orecrusher, four cyanide leaching pads, and a processing facility near the Annie Creek which are not part of the site.
Wharf Resources installed a french drain partially through the old tailings to divert spring waterfrom contacting the tailings. Additional lateral drains were installed to divert water percolatingthrough the waste rubble facility around the tailings. The Old Reliance Tailings are now coveredby about 60 to 150 feet of waste rock deposited as a result of current activities on the site. Topsoil and grass have been placed over the waste rock and old tailings to minimize erosion. The waste rubble facility was permitted under the state. Waste rock is continuing to be depositedas part of the active mining operation under a State mining permit. A history of operations and site related activities are presented in Table 1.
|Gold ore was processed at the site using a cyanide leachingmethod.|
No mining activities were conducted at the site.
The US Geological Survey monitored water quality in SpearfishCreek.
Wharf Resources began operating a gold recovery facility at thesite. The facility is currently active.
Wharf Resources monitored surface water quality in Annie Creekdownstream from the tailings pile.
Wharf Resources monitored water quality in Annie springs at thesite.
SDDENR submitted a Preliminary Assessment of the site to U.S.EPA Region VIII Office in Denver, Colorado.
An EPA Field Investigation Team monitored the tailings, surfacewater, sediment, and groundwater in the vicinity of the site.
Wharf Resources monitored fish tissue in Annie Creek andSpearfish Creek.
EPA evaluated the site under the Superfund Hazard RankingSystem (1).
The site was proposed for the Superfund National Priorities List.
A site visit was conducted by Joe Hughart, Environmental Health Specialist, Tina Forrester,Toxicologist, and Susan Muza, Regional Representative on October 15-18, 1991. Site data inState and County government files were reviewed. ATSDR representatives met with personnelfrom the South Dakota Department of Environmental and Natural Resources (SDDENR) and theSouth Dakota Department of Health (SDDOH). County health nurses, local physicians, and theSpearfish Canyon Homeowners Association were also contacted. A tour of the Wharf ResourcesMine was conducted by the mine operator. Annie Creek was observed from the WharfResources property boundary to the confluence with Spearfish Creek.
It was observed during the site visit that:
|-||Direct contact with the tailings at the headwaters of Annie Creek is unlikely since the site is in an isolated location and the Reliance Tailings are currently under 50-160 feet of waste rock.||-||Most of the residences along Annie and Spearfish Creek are seasonal vacation homes.|
The Annie Creek Mine Tailing Site is located in Lawrence County. Ninety percent of theresidents of Lawrence County are white, 1% are Hispanic, and the remaining population belongto other ethnic groups. There are fewer residents below 18 years of age in Lawrence County,compared to the state population, and slightly more residents are 18 to 64 years old. Thepercentage of residents over 65 years of age is comparable to the state average. Ten percent ofthe families in Lawrence County live below the poverty level. The per capita income ofLawrence County residents slightly exceeds the state per capita income. Over 75% of LawrenceCounty residents are high school graduates, and about 13% have 4 or more years of college (2).
There are 20 homes located along the Annie Creek and Spearfish Creek (near its confluence withAnnie Creek). Fifteen residences are vacation homes with limited annual occupance, three arepermanent residences, and two are summer homes. The number of occupants of these residencesare unknown. One permanent residence is located on Spearfish Creek, upstream from theconfluence with Annie Creek. Two other residences are located one mile from the confluence onSpearfish Creek. The only residence in the Annie Creek drainage is the Kannenberg cabin whichis used as a vacation home. This cabin is located 3/4 miles from the site. A commercial districtis located in Lead, about 3.5 miles east of the site. Terry Peak Ski Resort is located one mile south of the site (3).
The primary industry in the immediate vicinity of the site is mining (about 44% of the work forceare employed as miners). The closest mines beyond the site are located about 1.2 milesnortheast. About 17% of the work force are employed in professional services, 2% are employedin construction, and 4% in manufacturing (4). Less than 1% of the work force are employed inagriculture. There are no farms in the immediate vicinity of the site. A fish hatchery is located at Spearfish, about 12 miles downstream from the site.
The closest health care facilities are located in Lead, about 3.5 miles east of the site. The closestschool to the site is a high school in Lead, located about 4.2 miles east of the site. Elementaryschools are located about 4.7 miles east of the site. Solid waste from several other mines arepresent in the Spearfish Creek watershed. There are no records of releases of hazardoussubstances in Lead or in Spearfish in the EPA Toxic Release Inventory database.
Natural Resource Use
Groundwater is used as a source of drinking water for Wharf Resources. The on-site well is 360feet deep and draws water from the Pasahapa Limestone, the Englewood Formation (limestone),and the Whitewood Formation (dolomite). Depth to the saturated zone in this well is 288 feet. Rocks in the vicinity of the site consist of fractured Tertiary igneous intrusives andMississippian-age limestones. The limestone formations lie along the flanks of the Black HillsUplift, the core of which consists of igneous intrusive rocks. The igneous rocks generally do notyield sufficient water to function as aquifers. Some water wells in the area draw water from thelimestones. Limestone wells in the area generally yield 5 to 100 gallons per minute, withmaximum yields of about 4,000 gallons per minute. The saturated zone in limestone wells isusually located 100 to 300 feet below ground surface (5).
Springs forming Annie Creek are located along the flanks of the tailings pile. Annie Creekdischarges into Spearfish Creek about 2 miles southwest of the waste rubble facility. SpearfishCreek provides recharge to water wells completed into alluvium. Soil on the Reliance Tailingsite consists of mining spoil and colluvium. The soil is not used for farming in the area.
Thirteen residences have groundwater wells. Most wells are shallow (10-50 feet) and areprobably completed in the alluvium. Only one residence uses surface water for householdpurposes (toilets, washing dishes, but not drinking water).
The area around Annie and Spearfish Creek are primarily used for recreational activities. Recreational use is limited to summer months and activities include hiking, fishing and hunting. No residents use Annie Creek for fishing, only a few use the area for hiking. The area ofSpearfish Creek near Annie Creek is used for recreational purposes only. An annual motorcyclerally is held in Sturgis, South Dakota, and people camp along Spearfish Creek during that period. The rally is usually held during the first week of August. The Terry Peak ski slopes and lodgeare located about 1 mile south of the site.
Trout fishing is popular in streams below the site. The State of South Dakota has designatedAnnie Creek as a cold water marginal stream for trout. The annual fish harvest for Annie Creekis about 65.0 lbs/acre. Spearfish Creek has been designated by the state as a cold water stream,excellent for trout, approved for immersion and limited contact recreation. The annual fish harvest for Spearfish Creek is about 200 lbs/year.
Government agencies routinely collect information on the health of the population within theirboundaries. Using state health data bases it may be possible to determine whether certain healtheffects occur at a higher rate than expected in a given area. The State does not maintain chronicdisease registries (i.e cancer or birth defect registries). Local physicians interviewed by ATSDRreported no diseases or symptoms that could be positively associated with exposure to arsenic inthe environment in the vicinity of the site. The physicians did report that occupational healthstudies had been conducted on workers at a mine near Deadwood for chronic obstructivepulmonary disease and lung cancer (6,7).
ATSDR contacted the SDDENR, SDDOH, and a member of the Spearfish Canyon HomeownersAssociation to determine if local residents have health concerns about the site. The followingconcerns were reported to ATSDR:
- Citizens were concerned about the impact of mine tailings from Annie Creek on the municipal water supply.
- Citizens were concerned that residential wells that draw water from the alluvial aquifer along Spearfish Creek were impacted by tailings from Annie Creek.
- Citizens were concerned that the trout that inhabit Annie and Spearfish Creek were contaminated.
There were no symptoms or illnesses reported as community health concerns in relation toreleases of heavy metals into the environment at the Annie Creek (Reliance) Mine Site.
ATSDR will address these concerns in detail in the Public Health Implications section of this public health assessment.