PUBLIC HEALTH ASSESSMENT
CEDAR RAPIDS, LINN COUNTY, IOWA
The Electro-Coatings site, owned by Electro-Coatings, Inc., is located at the facility of Electro-Coatings, Inc., in Cedar Rapids, Linn County, Iowa. The site occupies approximately one acre near the north shoreline of Cedar Lake. The company has been operating since 1947 as a plating facility that uses chromium, nickel, copper, and cadmium in various plating processes.
Elevated levels of total chromium (Cr) and hexavalent chromium (Cr VI) were detected in groundwater samples taken from industrial wells at Hawkeye Rubber, Inc. Further investigation determined that a buried tank containing chromic acid was leaking into the surrounding soil and leaching into the bedrock aquifer from the adjacent Electro-Coatings facility. Later, a cadmium-plating line was also found leaking contents into the soil at Electro-Coatings, and cyanide was detected in groundwater samples taken from the Hawkeye Rubber industrial wells. The site was then placed on the National Priorities List (NPL), and the Iowa Department of Natural Resources (IDNR) conducted groundwater sampling that included the Hawkeye Rubber wells. These industrial wells are also used to monitor groundwater in the area. The two groundwater samples tested contained elevated levels of chromium.
A Remedial Investigation/Feasibility Study (RI/FS) was conducted at the site. Groundwater samples contained volatile organic compounds (VOCs), cadmium, and chromium at levels of concern. Cedar Lake samples contained arsenic and chlordane. Those contaminants are not likely associated with the site. Groundwater contamination investigations concluded that no public or private water supplies have been affected by site contaminants.
The people in the community have not expressed any concerns about the site. A public meeting was held in the Summer of 1994 by IDNR, the U.S. Environmental Protection Agency (EPA), and the Iowa Department of Public Health (IDPH) to address any local issues or questions about the site.
The Agency for Toxic Substances and Disease Registry (ATSDR) and IDPH concluded that the site poses no public health hazard. Potential exposure pathways have been identified, but exposures can be avoided if recommendations made in this document are followed. Recommendations include monitoring municipal wells and not allowing private well development west of the site.
The available information does not indicate that people are or have been exposed to site related contaminants at levels which would cause illness or disease. Although no health follow-up actions are indicated at this time, ATSDR and IDPH will evaluate additional data that may become available for any indicated follow-up health actions.
Electro-Coatings, Inc., has been operating since 1947 as a plating facility that uses chromium, nickel, copper, and cadmium in plating processes. The site is located in an industrial section of Cedar Rapids, Linn County, Iowa, near the north shoreline of Cedar Lake, east of the Cedar River (Figure 1). The Electro-Coatings site occupies approximately one acre. Municipal water from shallow wells along the Cedar River serves an urban population of approximately 175,000 people (2000 census). The city well field closest to the site is approximately 2,000 feet west of the site. This well field comprises city wells CW-1, 2, 3, 6, 8, & 9. There are no private residential wells located nearby. Residential areas are connected to the public water supply system.
On March 4, 1976, elevated levels of total chromium (Cr) and hexavalent chromium (Cr VI) were found in the cooling water discharged from Hawkeye Rubber, Inc, an industrial facility located adjacent to the site on the west side. The contamination was traced to a leaking underground storage tank containing chromic acid at the Electro-Coatings plant. The leak contaminated the underlying soil and leached into the shallow and bedrock aquifers immediately underneath the site. Soil contamination was confined to soils located directly underneath the leaking tank at the Electro-Coatings facility. Two Hawkeye Rubber industrial wells, PW-1 & 2, located approximately 400 feet west-southwest of the Electro-Coatings facility tap into the contaminated bedrock aquifer. After the discovery of Cr VI in the cooling water at Hawkeye Rubber, four monitoring wells (MW 1-4) were installed around the Electro-Coatings facility. Chromium has never been detected above laboratory quantitation limits in water from those wells.
The leaking tank and most contaminated soil underneath were removed in 1976. A new tank and cement floor were installed. Ferrous sulfate (18,000 pounds) and sulfuric acid (6,600 pounds) were applied to the soil to reduce Cr VI to trivalent chromium (Cr III).
In 1983, a cadmium-plating line at Electro-Coatings, Inc., was found to be leaking, and cyanide was detected in groundwater samples taken from the two Hawkeye Rubber industrial wells. In 1989, the Electro-Coatings site was placed on the NPL because of chromium released to the environment as a result of facility operations. On April 16, 1990, A Preliminary Public Health Assessment (PPHA) for the site was prepared by the Iowa Department of Public Health (IDPH) under a cooperative agreement with ATSDR. In the PPHA, IDPH concluded that the site posed a potential public health concern because of potential risk to human health caused by the possibility of chronic exposure to hazardous substances via ingestion of groundwater (1). Additional groundwater, surface water, and sediment sampling were recommended to define the extent of contamination at the site.
On September 13, 1990, the Iowa Department of Natural Resources (IDNR) conducted groundwater sampling tests that included the two Hawkeye Rubber industrial wells. Test results indicated elevated levels of chromium were present in the well water.
Deposits of soil and rock at the site area contain approximately 15-30 feet of alluvial deposits (sands with gravel and silts) overlying between 2-25 feet of glacial deposits (predominantly consisting of eroded Kansan glacial drift). The drift consists of thin and discontinuous silt and clay tills, with minor amounts of sand and gravel. Glacial drift is completely eroded in some areas; therefore, alluvial sediments come into direct contact with the underlying bedrock in those areas. Bedrock beneath the site consists of dolomite and limestone of Middle Devonian and Upper Silurian Periods. The limestone and dolomite contain numerous fractures and are slightly to moderately weathered. The Maquoketa shale of the Ordovician Period lies approximately 200-300 feet beneath the bedrock surface.
The two primary aquifers at the site include a shallow sand and gravel aquifer and the Silurian-Devonian bedrock aquifer. Both are hydrologically connected where the alluvial deposits are in direct contact with the bedrock. While the sand aquifer flows in a westerly to southwesterly direction (Figure 2), the bedrock aquifer flows in a southwesterly direction (Figure 3). Both may eventually discharge into the Cedar River.
A Remedial Investigation/Feasibility Study (RI/FS) was conducted at the site between February and August 1991 (2). As part of the RI/FS, 12 soil borings were drilled and 10 monitoring wells were installed (Figure 4). All new and existing wells were sampled to evaluate the nature and extent of groundwater contamination. Groundwater sampling was performed in three rounds, one in March 1991 and two in September 1991. Of the monitoring wells, six tapped into the shallow sand and gravel water table aquifer and three tapped into the bedrock aquifer. Groundwater samples from the site indicated the sand and bedrock aquifers were both contaminated with volatile organic compounds (VOCs), cadmium, and Cr VI. Monitoring wells MW-6D, 8D, & 10D, and production wells PW-1 & 2 tap into the bedrock aquifer. All other monitoring wells tap into the sand aquifer.
Further ground water investigation of VOCs determined that Electro-Coatings was the probable source of trichloroethene (TCE), dichloroethene (DCE), and trichloroethane (TCA) contamination (3). However, tetrachloroethylene (PCE) contamination was found at higher concentrations adjacent to the Hawkeye Rubber facility. This suggests that Hawkeye Rubber may have been contributing to the PCE contamination.
In September 1994, IDNR determined that remedial action should include groundwater monitoring with a contingency for groundwater pump-and-discharge to the publicly owned treatment works (POTW). This remedy acknowledged the containment of contaminated groundwater by a nearby production well (PW-1) operated by the Hawkeye Rubber Company. Prior to this, actions had been taken to address site contamination. These actions included:
- Closure of a chromium dipping tank in 1976.
- Leak prevention / monitoring measures in all chrome plating tanks.
- Removal of chromium contaminated soil in 1992.
- Placement of the site on the state Registry of Hazardous Waste or Hazardous Substance Disposal Sites. This action prevents sale or significant change in use of the property without approval by IDNR. Furthermore, notice of this listing was also recorded on the property deed.
Historically, PW-1 has removed contamination in the groundwater by inducing groundwater flow which has drawn the contamination toward the well. This in turn decreases the volume and area of contamination in the groundwater. If this pumping ceased or became ineffective, the contingency component of this remedy would achieve the same result. This remedy contains no requirements for continued operation of PW-1. Instead, provisions for a contingency action are provided in the event PW-1 ceases pumping or is found not to effectively prevent off-site migration of contaminants, other than to PW-1. If water quality monitoring reveals off-site migration of contaminants from the Electro-Coatings site above drinking water standards, contingency actions would be required. The contingency action would involve installation of a new recovery well (or wells as needed) to provide adequate containment of groundwater contamination. Treatment of this water would be provided, if necessary, prior to discharge into the sanitary sewer under a pretreatment agreement with POTW. Treatment would likely involve reduction of the hexavalent chromium to trivalent chromium by chemical addition.
Groundwater monitoring will continue as long as contaminants associated with the site exceed Maximum Contaminant Levels (MCLs) for drinking water (i.e., 0.1 mg/L for chromium). If water quality monitoring reveals off-site migration (other than to PW-1) of contaminants from the Electro-Coatings site above the MCL for that contaminant, then a monthly water quality monitoring frequency will be instituted, at least until contaminant levels no longer exceed MCLs. If MCLs are exceeded for three consecutive months, then the contingency action will be required unless it can be demonstrated that contaminant levels are decreasing. Monthly monitoring would continue until MCLs are no longer exceeded or until the contingency action plan is initiated.
The objective of the contingency plan is to prevent off-site migration of groundwater contaminants, other than to PW-1 or any new recovery well that may be installed. Contingency action(s) may include increased pumping from PW-1 or installing and operating a new recovery well(s). In either event, water withdrawn can be used as process water by Electro-Coatings or Hawkeye Rubber and treated and discharged into the POTW.
On November 10, 1992, representatives from the Iowa Department of Public Health (IDPH) and the Linn County Health Department visited the Electro-Coatings site. Areas of special interest were the site property boundaries and monitoring well locations. A tour was conducted of the location where the former dip tank leaked into the sand aquifer.
Site access was not fully restricted. The Electro-Coatings facility is surrounded by privately owned industrial properties and adjoins the northern shoreline of Cedar Lake. Traffic in the area is primarily commercial in nature.
An off-site area surrounding Cedar Lake was of special interest. Access to Cedar Lake was not restricted. Signs were posted near public access points to inform the public not to swim in the lake and that the fish in Cedar Lake should not be eaten. These warnings were posted because elevated levels of chlordane had been detected in lake water (4). However, the chlordane contamination was not from operations conducted at the site.
On September 11, 1995, IDPH revisited the site. No changes in the site's physical conditions or access were noticed since the previous visit in 1992.
At the time this document was being prepared, no changes in the site's physical conditions or access were noticed since the previous site visit.
Cedar Rapids has a population of approximately 175,000 people. The closest residence is within a half mile north-northeast of the site. Approximately 25% of the population are below 18 years of age; while approximately 13% are 65 or older. Approximately 97% of the population is White with the other 3% of the population divided equally among Asians, Blacks, and Hispanics. The cities of Hiawatha and Marion (with populations of 4,986 and 20,403 people, respectively) are also located north and northeast of the site.
The site is in an industrial area within the city limits of Cedar Rapids, Iowa, near the north shoreline of Cedar Lake. The lake is approximately 200 feet south of the source area at the site and is used as a cooling water reservoir by several of the adjacent industries. The Cedar River is located approximately 2,000 feet west of the site and flows in a southeasterly direction. The Cedar River is used for fishing and recreational activities. A swimming and fishing advisory has been issued for Cedar Lake, and signs have been posted. However, the lake is accessible to the public, and people may swim or fish there if they were unaware of the advisory.
Natural Resource Use
Forty of the forty-two Cedar Rapids municipal wells are within three miles of the Electro-Coatings facility. The closest city well (CW-6) is approximately 2,000 feet away. All municipal wells are either hydrologically up-gradient or cross gradient from the site and are in the sand-gravel aquifer. Two production wells owned by Hawkeye Rubber (PW-1 and PW-2) are located approximately 400 feet west-southwest of the site. Both of those wells are located in the dolomite bedrock and are approximately 50 and 176 feet deep, respectively. Groundwater from these wells are not used for human consumption, nor do people come into contact with the water. The well water is used only in closed-system processes. There are no other private wells within a three-mile radius of the site (1,3).
Using state health databases, special studies, or other relevant health outcome databases, it may be possible to determine whether certain health effects are higher than expected in areas surrounding hazardous waste sites. This section introduces the databases available.
IDPH maintains the vital statistics (birth, death, and fetal death reports). The University of Iowa maintains the cancer and birth defects registries. The state cancer registry has collected data since 1969. The birth defects registry has collected data since 1985.
Information derived from the state cancer and birth defects registries may make it possible to determine if health effects are related to exposure from site contaminants. People have not been exposed to the contaminants of concern at this site. Therefore, no adverse health outcomes would be expected. Also, area residents have not mentioned any specific health concerns related to the site. For these reasons, health outcome data has not been evaluated for this site.
A public meeting was held on July 26, 1994, in Cedar Rapids. Fourteen people attended this meeting including two representatives from IDPH, two representatives from EPA, three representatives from IDNR, two representatives from Electro-Coatings, Inc., two representatives from the Cedar Rapids public water supply, two representatives from the League of Women Voters, and one private citizen. The concerns identified were:
- Why has there been such a long time lag between identification of the problem and finally deciding what to do about it?
- Is the drinking water standard for chromium permanent, or will it become smaller?
- How much chromium initially leaked?
- Was chromium found in water and sediment samples from Cedar Lake?
- What is going to happen to Hawkeye Rubber?
All of the above questions are addressed in the Community Health Concerns Evaluation section of this report.