Kohnen & Lammers Chemical Co. Ecological Risk Assessment
On this page:
- Site description and history
- Screening Level Risk Assessment (SLERA)
In this section, the history of the site, along with endangered species known (or suspected) to be at the site, is described. Information about the historical and current land-use, as well as types of habitats, and known or suspected sources of contamination.
Also known as the Lammers Barrel Factory Site, the site, at the corner of East Patterson and Grange Hall Roads, Valleywood Subdivision, Beavercreek, Ohio, was a solvent reclamation facility until it was destroyed by a severe fire in 1969. There are no buildings at present. The site is bordered by a residential neighborhood to the east and southeast, the Little Beaver Creek to the north, and commercial developments to the south and west.
Little Beaver Creek flows east from the site 3 miles to Beaver Creek, which flows south for another mile to the Little Miami River, which continues south about 50 miles to the Ohio River.
The Bellbrook Quadrangle wetland map was not available during the preparation of this report, so the Soil Survey of Greene County, Ohio, 1978, USDA SCS, was consulted for an approximation of the presence of downstream wetlands. Marshes are not indicated between the site and the Little Miami River, or along the river within Greene County. The main soil along the creeks is the Sloan silty clay loam, a mottled alluvial floodplain soil with a seasonally high water table and subject to flooding. The section closest to the site is classified as Sloan-Urban land complex, differentiated by the addition of 2-5 feet of fill, but otherwise sharing the same physical limitations. The Sloan mapping unit is roughly 200 to 450 yards wide along the creeks. Much of it is cleared, but the creeks are bordered by narrow wooded strips, which would be classified as intermittent or seasonally flooded broad-leaved deciduous forested palustrine wetlands.
Threatened and Endangered Species
The following federal endangered species are listed for Greene County:
Screening Level Risk Assessment (SLERA)
For this site, the Region 5 ecologist performed the Ecological Risk Assessment, including calculation of Hazard Quotients (HQ), deciding on potential assessment endpoints and conceptual site models (See ERA Guidance Step 3 for more information on endpoints and site models).
This section describes the likely sources of contamination, what the contaminants are, and what plants and animals at the site are likely to be affected by those contaminants and in what manner.
Contaminants of Potential Ecological Concern (COPECs)
A contaminated groundwater plume extends east from the site. The main contaminants are vinyl chloride, chloroethane, methylene chloride, and cis 1,2-dichloroethene.
Fate, Transport, and Ecotoxicity
Only those chemicals likely to contribute to the potential ecological risks of the site are discussed in this section. This procedure is followed because the screening level ecological risk assessment (SLERA) is based on a screening comparison of the concentrations of COPECs with benchmark guidelines by media (soil, sediment, or surface water). This numerical comparison results in a Hazard Quotient; if the HQ is greater than one, the potential for ecological risk by that COPEC is present. (See Step 2 of the Guidance for more details.)
The benchmark values are sufficiently conservative so that chemicals detected at concentrations below the guidelines are not expected to exhibit significant ecological effects, even if fully bioavailable. Since fate, transport and toxicity variables do not modify the outcome of the screening (these effects are embedded in the derivation of the particular guidelines), discussions of these processes for the chemicals screened out are unlikely to contribute meaningful information to the SLERA.
For all the substances, volatilization is a more important removal process than degradation. Dichloroethene does not degrade much except in anaerobic (lacking-air) conditions, with vinyl chloride as the unfortunate product. Vinyl chloride does not appreciably degrade unless exposed to light, but volatilization is of course rapid in this situation. Chloromethane physically degrades and anaerobically biodegrades, and methylene chloride biodegrades, both aerobically and anaerobically, but the rates are usually slower than volatilization. All of the compounds readily leach, but none of them bioconcentrate.
The primary toxicological effects are central nervous system depression and liver damage. Mortality is usually caused by respiratory inhibition, however the lethal inhalation doses are high (LC50s in 10,000s ppm). Methylene chloride, vinyl chloride and chloroethane are animal carcinogens. The carcinogenicity of dichloroethene apparently has not been determined.
See Toxicity Profiles for more information on the toxic effects on wildlife by various compounds.
Exposure Pathways and Potential Receptors
Two potential exposure pathways are volatilization from the subsurface to above-ground receptors (plants and animals), and discharge of the contaminated groundwater plume to the Little Beaver Creek and exposure to aquatic receptors. The former process is unlikely to result in ecotoxicologically significant exposures, and will not be considered further. It is not presently known whether the groundwater plume is discharging to the creek, but, for the sake of this report, it is assumed that this discharge is happening.
SLERA: Risk Calculations/Exposure Estimates (Step 2)
This section includes calculations of Hazard Quotients and calculated estimations of risk by COPECs to potential receptors in different media (soil, sediment, surface water). This step involves the comparison of the concentrations of COPECs with benchmark guidelines by media (sediment, soil, surface water). If the maximum concentration of a chemical found at the site exceeds the screening benchmark guideline, then there is the potential for risk and further study is needed to clarify that risk. (See SLERA Step 2 for more information on the screening process, including calculating Hazard Quotients.)
Ecotoxicological Benchmark Values and Hazard Quotient Calculations
The Screening Level Ecological Risk Assessment (SLERA) is based on a screening comparison of the concentrations of COPECs with benchmark guidelines by media.
The lowest AQUIRE aquatic LC50 is used to derive an aquatic benchmark value by dividing by a conversion factor of 100: 10 to convert to a LOAEL (Lowest Observable Adverse Effects Level) times 10 to convert to a NOAEL (No-observable Advserse Effects Level):
190 mg/l ÷ 100 = 1.9 mg/l (1900 ppb)
The SLERA is performed with the following conservative assumptions:
- Bioavailability - 100%;
- Area use factor - 100%;
- Contaminant level - maximum groundwater concentration.
The maximum groundwater sample concentrations are as follows:
- Vinyl chloride (320 ppb)
- cis 1,2-dichloroethene (180 pbb)
- Methylene chloride (100 pbb)
- Chloroethane (78 ppb)
These are roughly one order of magnitude less than the calculated aquatic benchmark value of 1900 ppb. The site does not present a significant potential ecological risk, based on presently available data, because the maximum groundwater concentrations are well below the calculated No Observed Adverse Effect Level (NOAEL).
The carcinogenic risk to ecological receptors is not quantitatively assessed, but the risk is probably low because the compounds rapidly volatilize at the surface thereby reducing both the concentration and duration of exposure to any individual receptor.
Uncertainty risks are intentionally overestimated by the conservative assumptions discussed above, and especially by the assumption that the groundwater concentrations will not dilute upon discharge to the creek. The risks may be underestimated by the qualitative characterization of carcinogenic risk, and by reliance on residential well data for the maximum contaminant concentrations in the plume.
The available data do not indicate a significant potential ecological risk. There is no compelling ecological justification for Superfund involvement at this site.
September 1995 - Screening Level Ecological Risk Assessment completed.
Contact: James Chapman, Ecologist (firstname.lastname@example.org)