ZIONSVILLE, BOONE COUNTY, INDIANA
The Indiana State Department of Health (ISDH) conducted a health consultation to determine whether nearby private wells are being impacted by the migration offsite of groundwater contamination from Third Site.
Third Site is a vacant tract of land approximately 2 acres in size located north of Zionsville, Boone County, Indiana. Zionsville is approximately 15 miles northwest of Indianapolis. The site is on the east side of U.S. Route 421 about one mile south of State Route 32. It is bordered on the east and northeast by the Northside Sanitary Landfill (NSL) Superfund site, on the south by Finley Creek, on the west by U.S. Route 421, and on the north by a residential property, a construction recycling facility, and the EnviroChem Corporation (ECC) Superfund site. The ECC Superfund site is located immediately north of Third Site. Potentially responsible parties (PRPs) are remediating ECC and Third Site as one site. The land west of U.S. Route 421 is pasture land for a commercial horse breeding facility. The site is situated in a primarily agricultural area. Some commercial and industrial facilities are also in the area.
A home and recreational pond (Bankert Pond) were built by the property owner in 1986. Bankert Pond was created by excavating soil 15 feet deep. The excavated soil was used to build a berm on the three sides of the pond and to grade the area between the pond and Finley Creek.
Finley Creek flows southwest into Eagle Creek (approximately 2,000 feet southwest of the site). Eagle Creek flows fifteen miles downstream into Eagle Creek Reservoir, which is a municipal drinking water source for the city of Indianapolis. A ditch is located between Third Site and the NSL site.
Third Site was used in the mid to late 1970s by the EnviroChem Corporation (ECC) for tank and drum storage, and for truck parking. The United States Environmental Protection Agency (EPA) staff believes these activities caused soil and groundwater contamination. Storage and/or disposal activities have not occurred since 1983. Soil and groundwater samples taken in 1987 and in 1992 by the companies determined who was responsible for the contamination. Samples taken in 1998 by EPA contained volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) in soil, groundwater, and surface water.
In the spring and summer of 1996, a contractor completed the "Finley Creek Realignment Project." The project consisted of shifting a portion of Finley Creek 40 feet away from an on-site pond and from the source area of soil contaminants. This was done to prevent the potential release of contamination into Finley Creek. An outfall pipe was also installed from Bankert Pond to the new bank of the realigned Finley Creek to allow overflow discharge from the pond.
In October 1999, an Administrative Order (AO) was signed between EPA and the potentially responsible parties for completion of a study called an Engineering Evaluation/Cost Analysis (EE/CA) for the Third Site. Samples were taken at that time and in 2000 to determine the nature and the extent of VOC contamination at the site so cleanup alternatives could be evaluated and a removal action could be selected. The investigation included collecting soil, groundwater, surface water, and sediment samples. The investigation was finalized in October 2000; the EE/CA documented analytical results and provided a comparison of cleanup alternatives for four areas of contamination. The EE/CA also included analytical results of samples from private water supply wells in the area of investigation of Third Site. The following compounds were found in the soil and groundwater:
- tetrachloroethene (PCE)
- trichloroethene (TCE)
- cis-1,2-dichloroethene (cis-1,2-DCE)
- vinyl chloride
- trans-1,2-dichloroethene (trans-1,2-DCE)
- 1,1-dichloroethene (1,1-DCE)
The nearest private water supply wells are on the property where Bankert Pond is located. Those parcels of land are up gradient of Third Site. Other private water supply wells in the near vicinity of Third Site include one that is approximately 300 feet south of Finley Creek; two at residences that are more than 1,500 feet southwest of Third site; and one at a residence that is more than 3,000 feet southwest of Third Site. The majority of the private water supply wells in the vicinity of Third Site are deeper than 100 feet. The depth of the well that is approximately 300 feet south of Finley Creek was not reported. The geologic setting in the vicinity of Third Site indicates that the private water wells are all screened below the confining layer and should be protected from shallow contamination.
Between April and May 2000, the potentially responsible parties' contractor collected private water supply well samples from four residential wells. Samples were collected from sinks and spigots and were analyzed for VOCs. As required, the two water wells located on the property north of Third Site were also sampled in May 2000. An additional well near the barn south of Finley Creek and Third Site was examined but not sampled because the pump was not connected to power or an outflow pipe hindered pump wiring required for sampling. All residential wells sampled were free from contamination (Figure 1) [1,2]. That information supports the theory that a confining layer is preventing or delaying vertical migration of the contaminants to private well water in the area.
In July 2001, a site visit was conducted at Third Site by staff from ISDH and IDEM. Monitoring wells on-site were secured and appeared to be in good condition. IDEM staff shared that remediation of Third Site is to include soil vapor extraction (SVE) and installation of a leachate system in Bankert Pond . Soil treatment should prevent continued migration of contaminants to groundwater, and the leachate system will also help prevent additional groundwater contamination.
Although volatile organic compounds are the contaminants of concern at Third Site, remediation, when implemented, should prevent additional groundwater contamination. Contamination is confined to the on-site Bankert Pond in the soil along the bank. Private wells were sampled in April and May 2000 that are within a 1-mile radius of the site. The private water wells are screened below the confining layer and should be protected from shallow contamination. Private well water samples collected in 2000 confirmed that the water is free from contamination.
The Indiana State Department of Health (ISDH) and ATSDR recognize that children are especially sensitive to the toxicity of some contaminants. ISDH and ATSDR recognize that children react differently than adults when exposed to contaminants in their environment. They are more likely to be exposed for several reasons. Children play outside more often than adults, increasing the likelihood that they will come into contact with chemicals in the environment. Because they are nearer to the ground, children breathe more dust, soil, and heavy vapors. Children are also smaller, resulting in higher doses of chemical exposure per body weight. The developing body system of children can sustain damage if toxic exposures occur during certain growth stages.
Children are not at risk from the private wells sampled because the well water is free of contamination.
Private well water within one mile of Third Site poses no public health hazard. Analysis of private well samples showed that the water is free of contamination from Third Site. Site remediation should prevent future groundwater contamination, and the confining layer should protect the area wells from becoming contaminated with contaminants that are present in shallow groundwater on the site.
No further recommendations are needed at this time. Remediation should continue as planned.
The Indiana State Department of Health will revisit the site if new information warrants further investigation.
- EPA. EPA Proposes Cleanup Plan for Third Site Location Fact Sheet. Chicago, Il: 2000 Nov.
- ENVIRON International Corporation. Engineering Evaluation/ Cost Analysis, Third Site. Northbrook, Il: 2000 Oct.
- Indiana State Department of Health. Memorandum for Third SiteVisit. Zionsville: 2001 Jul.
Garry L. Mills
Environmental Epidemiology Section
This Third Site Health Consultation was prepared by the Indiana State Department of Health under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation was begun.
Gail D. Godfrey
Technical Project Officer
Superfund Site Assessment Branch (SSAB)
Division of Health Assessment and Consultation (DHAC)
The Division of Health Assessment and Consultation, ATSDR, has reviewed this health consultation and concurs with its findings.
Richard E. Gillig
Chief, SSAB, DHAC, ATSDR