PUBLIC HEALTH ASSESSMENT
SALIDA, CHAFFEE COUNTY, COLORADO
The Smeltertown (SMT) site near Salida, Colorado, was proposed for inclusion on the National Priorities List in February 1992. Past operations on the 125-acre site included metals smelting (gold, silver, copper, and lead) from 1902 to 1920, and treatment of railroad ties by Koppers, Inc. and others from 1926 to 1946. The tie treatment operations area is now occupied by Butala Construction. CoZinCo, which has manufactured zinc sulfate monohydrate for use as a soil amendment and animal feed supplement since 1977, is currently on site as well as a trucking company and a peat moss packaging operation. There are approximately fifty homes located in the southern and eastern portions of the site.
Wastes generated on-site included smelter slags, soils contaminated with creosote drippings, other contaminated soils, process water holding ponds and associated sludges, spilled ores, and combined soils and sludges. Site contaminants include a wide array of polynuclear aromatic hydrocarbons (PAHs) and numerous metals which include arsenic, cadmium, chromium, manganese, lead, beryllium, zinc, and copper among others. Although some contaminant sources remain on site, many of the original site contamination sources have been removed from the site.
Most off-site contamination in soils (PAHs and metals) has been removed. However, further an evaluation of past air-borne deposition of contaminants needs to be made to determine if all contaminated soils have been identified. Residents southwest of CoZinCo, in the area of groundwater contamination by metals, are being provided with bottled water. CoZinCo is working with the Colorado Air Pollution Control Division to resolve air emission issues at their facility.
Citizens voiced health concerns at an ATSDR-sponsored public availability meeting. Health concerns encompassed air emissions, groundwater and soil. Symptoms most commonly described were sinus problems, irritated eyes, sore throat and arthritis. Several of the adverse health effects described are consistent with the release of sulfur-containing mists and other work practices at CoZinCo. Although acid mists have been substantially reduced, ATSDR recommends that a risk assessment be conducted for metals emissions from the CoZinCo subsite.
Some people have been or are being exposed to site-related contaminants via inhalation of ambient air and incidental ingestion of surface soil. Because of past, present and future exposures to lead, arsenic, polynuclear aromatic hydrocarbons, and of past exposures to manganese and zinc in surface soil, this site poses a public health hazard. Exposures to lead and zinc in groundwater pose a past public health hazard to groundwater users southwest of CoZinCo.
In February, 1992, the Smeltertown (SMT) site was proposed for listing on the National Priorities List (NPL) of sites that need to be addressed by the U.S. Environmental Protection Agency (EPA) for possible site cleanup action. The ATSDR is required to do a public health assessment of all sites listed or proposed for listing on the NPL.
The purpose of the public health assessment is to evaluate all implications to human health for people that live, work, or play in the vicinity of proposed NPL sites. To do this, ATSDR provides a detailed review of all site-related environmental data, collects and reviews local health outcome data, as appropriate, and seeks the site-related health concerns of the local community. ATSDR investigates public health concerns which come to light during the investigation, regardless of whether the health concern is strictly related to the site. This document contains the results of ATSDR's findings, along with recommendations to promote public health protection and to fill important data gaps as needed.
The SMT site is located in Chaffee County, Colorado, approximately one mile northwest of the City of Salida. The site is bounded on the north by County Road 150, the east by State Highway 291, and the south and west by the Arkansas River (1). The site covers about 125 acres and consists of areas involving past operations of Koppers, Inc., including tie treatment operations (now occupied by Butala Construction); current and past operations of CoZinCo, an old smelter, a trucking company, and a peat moss packaging operation (2)[Figure 1]. Past operations on the site included metals smelting (gold, silver, copper, and lead) from 1902 to 1920 and treatment of railroad ties by Koppers, Inc. and others from 1926 to 1946 (3). CoZinCo has manufactured zinc sulfate monohydrate for use as a soil amendment and animal feed supplement from 1977 to present (CoZinCo was incorporated at another site in 1970).
Wastes generated on-site included smelter slags, soils contaminated with creosote drippings, other contaminated soils, process water holding ponds and associated sludges, spilled ores, and combined soils and sludges. Site contaminants include a wide array of polynuclear aromatic hydrocarbons (PAHs) and numerous metals which include arsenic, cadmium, manganese, lead, beryllium, and zinc among others.
In characterizing the SMT site for the Hazard Ranking System (HRS), a system used to score the site for NPL candidacy, EPA identified eleven waste source areas which included past operations areas, drum storage areas, contaminated soils, slags, and sludges, and active ponds. Many of these sources have since been removed. Approximately 500 tons of creosote-stained soil were removed in 1986; approximately 625 tons of creosote-stained soil were removed in 1992 (4). Contaminated soil on CoZinco property was removed in April 1990 (5) and June 1992 (6). Additionally, contaminated soil was removed from residences west of CoZinco and from residences where creosote was used as driveway construction material (7). Remedial actions, including fence construction around or gravel coating over contaminated soil near the Smelter stack, are underway; permanent remedial actions for this area are under development (7).
On September 1-2, 1992, Harvey Rogers and Joe Spurgeon of ATSDR Atlanta, and Susan Muza, ATSDR Region 8, visited Salida, Colorado, and the Smeltertown site. Representatives of the EPA Office of External Affairs, the Colorado Department of Public Health and Environment (Colorado DPHE) Hazardous Materials and Waste Management Division, and Chaffee County accompanied ATSDR on the site visit to provide relevant background information and to answer citizen questions regarding each of their program responsibilities as relates to the SMT site. A drive-by tour of the site was provided by ATSDR Region 8 to additional health assessors in November 1993.
The purpose of the site visit was to gather pertinent environmental information concerning the site, and to obtain citizen information regarding their concerns for health implications as might be related to the site. The ATSDR personnel also met with management from the CoZinCo plant and Butala Construction to review environmental information regarding those facilities, while in Salida.
It was observed during the site visit that many of the eleven original site contamination sources listed in the "Hazard Ranking System" (HRS) package had been removed from the site. The contaminant sources remaining on site include subsurface creosote, large quantities of vitreous slag on the Koppers site, and some surface soils containing heavy metals. The east pond on the CoZinCo site was taken out of service in April 1993. Sediment and solids were removed from the pond and the liner was determined to be intact.
The Smeltertown site is largely industrial in character; however, there are approximately fifty homes located in the southern and eastern portions of the site. These include private homes, at least five rental units, and at least three mobile homes. Visitors noted during the site visit that much of the site is readily accessible to the public. ATSDR staff also observed that there was little evidence of small children in the immediate site area. This observation was supported by community resident statements during the "public availability session" held during the site visit.
The ATSDR visitors saw the major water sources for Salida and Poncha Springs while on the site visit. The ATSDR also saw both the Butala Construction operations and CoZinCo operations. For both visits, areas that have been cleaned up since the mid 1980's were pointed out to ATSDR. This information is important in analyzing past versus current potential human exposure pathways.
Demographic information is presented for Chaffee County, Salida, and finally for the area surrounding the Smeltertown site. In 1990, the county had a population about 12,700 people. The population was about 95% white, 2% black (including African-American), and 3% other races. Approximately 12% of the population were under age 10 in 1990, and 16.5% were age 65 or older. There were nearly 3 persons per household in 1990. The median value of owner-occupied housing units was $62,900. (8)
The town of Salida had a population of about 4,700 people in 1990. The population was about 96% white and the remaining 4% were all other races. Approximately 13% of the population were under age 10 in 1990, and 22% were age 65 or older. There were just over 2 persons per Salida household in 1990. The median value of owner-occupied housing units in Salida was $53,300 (8).
The block group in the census tract encompassing the Smeltertown site had a 1990 population of 332 people, of which 98% were white and the remaining 2% were all other races. Approximately 12% of the population were under age 10 in 1990, and 11% were age 65 or older. There were between 2 and 3 people per household in 1990. The median value of owner-occupied housing units was $73,800 (8). It should be noted that this block group comprises an area much larger than Smeltertown; it is estimated that about one third of the block group's population resides in the immediate Smeltertown vicinity.
Approximately 5200 people live within four miles of the Smeltertown site. About 200 people live within one mile of the site. It was noted at the public availability meeting that many of the people living in the vicinity of the site are retirees who moved to the area from other parts of the United States. Within the boundaries of Smeltertown, there was little evidence that there were many small children in the area. Smeltertown residents at the public availability meeting noted two children in the community, although there may be more. There are also two additional children living at the home on the Fish Hatchery grounds adjacent to SMT. There is a "bed and breakfast" home immediately south and west of the site.
The Smeltertown site is generally zoned industrial; however, zoning does not appear strictly enforced as evidenced by the continued allowance of new homes in the area. Land use in the general area of the subject site consists of the following: (a) industrial operations (CoZinCo), (b) rock-crushing related activities (Butala Construction), commercial activities (river rafting, bed and breakfast, automobile salvage yard, peat moss packaging and sales), (d) public use (fish hatchery), recreational use (fishing), (f) agricultural use (fields, livestock, horse farms), and (g) residential use. The smokestack is a National Historic Place and is visited by residents and tourists (9).
The residents of Salida obtain their drinking water from three major sources. These include Pasquale Springs, immediately north of Salida, the Salida Infiltration Gallery, about 1.5 miles south of the Smeltertown site and across the Arkansas and South Arkansas rivers from the SMT, and the Harrington Ditch surface water collection system located on the north fork of the South Arkansas River about 1 mile south of SMT. The water from the Harrington Ditch, which is mountain runoff, is chlorinated and filtered prior to use.
The nearby town of Poncha Springs obtains its water from a well located about 4 miles southwest of SMT. This well is also separated from SMT by two main rivers and is at a higher elevation than SMT, although it is included in the potentially affected area described in EPA's Hazard Ranking System. Based on hydrogeology, the well water of Poncha Springs will not be affected by groundwater contamination from the Smeltertown site.
Most Smeltertown residents obtain their drinking water from private wells and/or local springs; however, residents southwest of CoZinCo, in the area of groundwater contamination by metals, are being provided with bottled water. Most wells are thought to be less than 20 feet deep, and some are hand dug. Some private sources of drinking water are surface springs. Soils in this area are highly permeable, with a low capacity for holding water.
The Smeltertown site is located in the upper Arkansas Valley. Bedrock in this area is the clay, sand, silt, and gravel of the Dry Union Formation (10). The formation is overlain by glacial deposits. The subject site sits upon these glacial deposits approximately 80 feet above the Arkansas River. The Arkansas River is fished and rafted recreationally.
Colorado Department of Public Health and Environment (Colorado DPHE) maintains traditional health outcome databases such as cancer registries, mortality registries, and birth defect registries. Given the nature of the community's health concerns (see next section), and the limited current understanding of contaminant exposure pathways, it is considered premature and non-productive to review the state registries at this time.
ATSDR met with citizens of Chaffee County on September 1, 1992, to discuss community health concerns about the SMT site. Two separate "one-on-one" public availability meetings were held to allow individuals to discuss their concerns with ATSDR staff. Over forty citizens participated in these meetings. Most of the participants lived in the immediate Smeltertown area; however, residents of other parts of the county also participated.
Although the meetings were intended to gather community concerns about the entire Smeltertown site in general, most of the participants comments focused on current operations of the CoZinCo Plant as the subject of their concern. More specifically, most of the concerns were about the possible health impacts of air emissions from the CoZinCo plant. There were also several questions raised about the impact of SMT on the quality of drinking water obtained from wells and springs used by residents in the vicinity of SMT. In addition, a number of non-health concerns raised by community members, again primarily focused on air emissions from CoZinCo.
The primary concerns of the community included the following:
- Health concerns related to air emissions
(28 of 38 responses),
- Health concerns related to groundwater
(4 of 38 responses),
- Physical effects of air emissions
(16 of 38 responses)
Strong odors (acrid, pungent; and "rotten egg")
Damage to exterior car and house paint, and
- Health concerns related to vegetables grown in contaminated soil
(2 of 38 responses).
Symptoms related to health effects that were frequently mentioned by the community (25% or more of respondents) included:
- Sinus problems
- Irritated eyes
- Sore throat
Other health effects that were mentioned less frequently included:
- Sore nose
- Coughing during air episodes
- Choking sensation during air episodes
- Vomiting during air episodes
- Allergic symptoms
- Kidney/Urinary problems
- Skin cancer
- Increased Multiple Sclerosis in Salida
- Congestive Heart Failure
- Birth Defects, Learning Disabilities
Most of the above concerns were raised by the community as questions regarding the possibility of a relationship of these health effects to the CoZinCo air emissions. Those health concerns will be addressed in the Community Health Concerns Evaluation section.
The community concerns listed in this section are those of the 40 people who attended the public availability meetings. These concerns may not encompass all concerns people have about this site. Colorado DPHE Air pollution Control Division records indicate that they have received site-related complaints from the community for more than 10 years (11).